Linear Motion News

Explosion Proof Linear Actuators

Thu, 15 Jul 2021 13:15:05 -0400

Nook Industries offers a highly configurable line of modular linear actuators specially developed for explosion-protection zones. These linear actuators are are commonly used in bottling technology for explosive substances such as:

Alcohol
Benzene
Gasoline
Flammable Chemical Liquids

Available in a variety of lengths and drive properties, these linear motion systems can be designed and built to the exact requirements of the application. These linear actuators are specially developed for the explosion-protection field meet the highest safety standards in accordance with the following guidelines:

ATEX-R2014/34/EU
II 2G Ex h IIB T4 Gb
II 3D Ex h IIIB T125°C Dc
ISO 80079-36:2016
ISO 80079-37:2016
Technical Rules for Hazardous Substances (TRGS) 727

Toothed belt driven linear actuators axes from the ELZex and ELFZex series are certified for use in explosion-protection areas. The linear systems conform with the new EN ISO 80079-36 and -37 norm for mechanical explosion protection. Furthermore, the axes are ATEX-approved and can therefore be used in Zone 2 for gas and dust.

With this approach, it is possible to easily meet the demands of many new applications. The modular linear actuator systems are designed as a complete package to also include accessories such as limit switches and couplings with ATEX approval.

Learn More

Technical Features

Multiple installation positions
Maximum length 6000 mm (ELZex)
Maximum length 3000 mm (ELFZex)
Allowable surface temperature 125°C
Repeat accuracy ± 0.1 mm
Traverse speed <1 m/s
Toothed belt design Conti HTD 5M/8M HP-PAZ antistatic

Use Our Linear Actuator Product Selector

Easily design your own linear actuator system based on your unique application with the DESIGN GUIDE PRO tool. Enter your parameters to determine the best product fit.

Get Help with an Application

Special circumstances can sometimes require tailor-made solutions. Often the problem cannot be solved by just using individual stainless components.

Our engineering team not only advises you on the provision of the ideal linear unit for your machine design, but also supports you with questions about production in clean rooms. As always, our Engineering Support Teams are always on stand-by to help with your linear motion application.

Product Spotlight: Clean Room Linear Actuators

Thu, 08 Jul 2021 10:11:19 -0400

Linear Motion Technology for Clean Rooms

What special requirements do our customers usually have in markets such as chemical, pharmaceutical, and semiconductor processing?

These work zones can be compared with hygienic dry areas in many respects. The built-in linear motion technology must be spray-proof and water resistant. Therefore, it is important that the mechanical components can be cleaned easily and effectively. In addition, the surface protects the internal mechanics from aggressive cleaning agents and corrosive chemicals due to their high resistance. Surfaces made of stainless steel are ideal for these applications.

In production in Clean Rooms, the concentration of airborne particles is kept particularly low to prevent defects and reduce losses. In recent years, increased quality standards have led to a high interest in clean room standards in many production facilities. Specific manufacturing functions can include filling, packaging, testing, sorting, and positioning.

Clean Room Solutions

How does our linear actuator technology meet the demanding standards of our customers?

For this purpose, Nook offers several linear actuator solutions in our portfolio. Stainless steel components have proven themselves to be very effective in work areas with stringent hygiene standards.

What makes our products so special?

The aluminum guide profiles of the linear actuators are clad with a stainless steel sheet (thickness 0.37 mm, material 1.4301) using a highly specialized process. This stainless steel casing provides the highest hygiene standards. In addition to the built-in rustproof components inside the linear actuator, the smooth outer surface of the system can also be cleaned very easily.

With its complete stainless steel sheathing, the axle is not only protected against coarse external influences, but is also particularly easy to clean due to its smooth surfaces. High-quality materials are used to effectively limit the abrasion of moving parts.

These linear axes have proven to be particularly useful in the food & beverage, pharmaceutical, chemical processing, and semiconductor industries. In addition, machine builders can easily integrate these linear positioning systems into their applications. Our modular linear actuator products can be tailor-made to integrate into production facilities in clean and clean rooms. Our customers can easily certify their automated systems in clean room areas.

Our linear axes are certified according to the following standards:

US Federal Standard 209E Class 1 – 100,000
VDI 2083 Class 1 – 6
ISO 14644-1 Class 1 – 8

Features

Low noise, low vibration, and low maintenance
High precision
Long travelling distances
Speeds up to 8 m/s and acceleration up to 10 m/s²
Space saving thanks to compact design
Long service life and high load capacity
Low weight
Aluminum profile with hardened and anodized surface
Unlimited individualization
Temperature range -25°C to 85°C
Resistant to environmental influences (dust or abrasive materials)
Certified for clean room technology

Explore Nook Clean Room Rated Actuators

Use Our Linear Actuator Product Selector

Easily design your own linear actuator system based on your unique application with the DESIGN GUIDE PRO tool. Enter your parameters to determine the best product fit.

Get Help with an Application

Special circumstances can sometimes require tailor-made solutions. Often the problem cannot be solved by just using individual stainless components.

Screw Jacks and Environmental Applications

Mon, 17 May 2021 10:48:12 -0400

From extreme temperatures to wet environments to outdoor challenges Nook Industries can meet them all.

Nook Machine Screw Jacks and Ball Screw Jacks offer the ability to lift, position, hold and support loads in a variety of industrial applications. These Jacks will provide excellent performance and reliability in the average indoor industrial facility with a dry environment and an operating temperature of 32^oF (0^oC) – 180^oF (82^oC).

However, not all applications are in these ideal conditions. Nook Industries offers many options to meet non-ideal conditions.

Jack Operating Conditions

A screw jack application operating condition is defined by two criteria. The first is the environment and the second is the temperature. The environment describes the area where the screw jack application is located. The temperature describes the ambient temperature in which the screw jack will be performing.

The screw jack operating conditions can be described by one of five environmental conditions and one of three temperature conditions. When the environmental conditions and/or temperature conditions are not “Standard” then screw jack modifications are required.

Environmental conditions

Standard - Indoor applications with dry conditions.
Wet/Harsh - Indoor applications with wet conditions (May include water, coolant, chemical cleaners).
Food Grade - Indoor applications with wet conditions requiring non-contact food grade considerations.
Outdoor - Outdoor applications.
Marine - Outdoor coastal applications with exposure to salt water and salt spray conditions.

Temperature conditions

Standard - Application with an ambient temperature of 32^oF (0^oC) – 180^oF (82^oC).
Low Temperature - Application where the low ambient temperature is in the range of -40^oF (-40^oC) – 32^oF (0^oC).
High Temperature - Application where the high ambient temperature is in the range of 181^oF (83^oC) – 300^oF (149^oC).

Screw Jack Modifications

Wet/Harsh Indoor Environments

Wet and harsh environments require updates to the screw jack deign to prevent corrosion. These screw jacks will have the standard hardware and fasteners replaced with stainless steel versions of the hardware and fasteners. The seal materials will be updated for improved chemical resistance. The paint will be updated to Epoxy paint to improve the corrosion resistance and resistance to other chemicals. If a boot is required, the boot material will be updated to improve the chemical resistance.

Indoor Food Grade Environments

Food Grade environments will usually require improved corrosion resistance and chemical resistance due to required cleaning procedures. These screw jacks will have the same updates as the Wet and Harsh environment screw jacks. Additionally, the grease used for lubrication in these screw jacks will be updated to a food grade grease.

Outdoor Environments

Outdoor environments require updates to the screw jack deign to prevent corrosion and resist weathering. These screw jacks will have the standard hardware and fasteners replaced with stainless steel versions of the hardware and fasteners. The seal materials will be updated for improved weather resistance. The paint will be updated to outdoor rated polyurethane paint for corrosion resistance and outdoor use. If a boot is required, the boot material will be updated for outdoor use.

Outdoor Marine Environments

Outdoor Marine environments require different updates then non-marine outdoor environments. These screw jacks will have the standard hardware and fasteners replaced with stainless steel versions of the hardware and fasteners. The seal materials will be updated for improved weather resistance. The paint will be updated to outdoor marine rated polysiloxane paint for corrosion resistance and outdoor use in marine environments. If a boot is required, the boot material will be updated for outdoor and marine use.

Operating Temperatures where the High Temperature Reaches 181^oF (83^oC) – 300^oF (149^oC)

High operating temperatures of 180^oF (83^oC) - 300^oF (149^oC) will require design modifications to ensure jack performance is maintained. Seal materials are changed to maintain performance in the elevated temperatures. Standard grease is updated to a high temperature grease that maintains performance at the elevated temperatures. Standard paint is updated to a high temperature paint that will not degrade at the elevated temperatures. If a boot is required, the boot material will be updated to prevent temperature related failure.

Operating Temperatures where the Low Temperature reaches -40^oF (-40^oC) – 32^oF (0^oC)

Low operating temperatures of -40^oF (-40^oC) - 32^oF (0^oC) will require design modifications to ensure jack performance is maintained. Seal materials are changed to maintain performance at these low temperatures. Standard grease is updated to a low temperature grease that maintains performance at these low temperatures. Standard paint is updated to an Epoxy paint that will perform at these low temperatures. If a boot is required, the boot material will be updated to prevent temperature related failure. Low temperature applications also have the hardware and fasteners updated to stainless steel.

OPERATING CONDITIONS	Exposed, Non-Painted Alloy Steel Surfaces	FASTENERS	SEALS	PAINT	GREASE	BOOTS
Standard Environment	No Modification Required	Alloy Steel	Standard Material	Enamel Paint	Standard Grease	Standard Material
Indoor Wet / Harsh Environments	Upgrade to Stainless Steel, Electroless Nickel Plating and/or Chrome Plating	Stainless Steel	Upgrade Material	Epoxy Paint	Standard Grease	Upgrade Material
Indoor Food Grade Environments	Upgrade to Stainless Steel, Electroless Nickel Plating and/or Chrome Plating	Stainless Steel	Upgrade Material	Epoxy Paint	Food Grade Grease	Upgrade Material
Outdoor Environments	Upgrade to Stainless Steel, Electroless Nickel Plating and/or Chrome Plating	Stainless Steel	Upgrade Material	Polyurethane Paint	Standard Grease	Upgrade Material
Outdoor Marine Environment	Upgrade to Stainless Steel, Electroless Nickel Plating and/or Chrome Plating	Stainless Steel	Upgrade Material	Polysiloxane Paint	Standard Grease	Upgrade Material
Standard Temperature 32^oF (0^oC) - 180^oF (82^oC)	No Modification Required	Alloy Steel	Standard Material	Enamel Paint	Standard Grease	Standard Material
High Temperature 181^oF (83^oC) - 300^oF (149^oC)	No Modification Required	Alloy Steel	Upgrade Material	High Temp Acrylic Resin	High Temperature Grease	Upgrade Material
Low Temperature -40^oF (-40^oc) - 32^oF (0^oC)	No Modification Required	Stainless Steel	Upgrade Material	Polyurethane Paint	Low Temperature Grease	Upgrade Material

Wet environment, outdoor environment, marine environment, food grade environment; Nook Industries has the screw jack options to meet these challenging environments. Temperatures below 32^oF (0^oC) or exceeding 180^oF (83^oC) Nook Industries has developed upgrades to meet these requirements.

Discuss your special environmental and temperature requirements with your Nook Industries Applications or Sales Representative. They will be able to apply the correct upgrades to ensure your jack will function in your application conditions.

Need help with an environmental application?

Explore Nook Screw Jacks

Getting Motion on Government Contracts

Tue, 20 Apr 2021 09:04:31 -0400

Specialized Support for Government Projects

With over 50 years of experience in providing linear motion solutions and services to a vast array of defense and infrastructure projects, Nook has the unique capability to see a variety of customer requirements and contractual flow-downs. In this blog, Nook's most experienced technical contract expert, Dan Piltz talks about the in and outs of supporting government projects.

Project Requirements

Project requirements can range from a simple napkin sketch to full design documents with multiple pages of complex contractual requirements. Many of the requirements that aren’t even on a design print can greatly impact our product. In my career, I have been exposed to many of the DoD requirements. Let's review some of the common requirements we see at Nook and their impact on both cost and lead time.

Commercial-off-the Shelf

Let's begin with COTS (Commercial Off the Shelf). COTS can make things simple and easy if it applies. Almost every customer as well as the Federal Government have allowances for COTS items to be purchased as-is. For something to be COTS, it must be commercially available for anyone to buy. Our team knows that If someone would call up and ask for a part number out of the catalog and then apply pages of terms and conditions, it would be worth the discussion if it can be classified as COTS. Many of our projects involve levels of customization from a COTS product; often in this case it becomes a custom product subject to the applicable contractual requirements.

FAR and Buy American

There are many FAR systems (Federal Acquisition Regulation). Here is the government's own explanation “The FAR is a substantial and complex set of rules governing the federal government’s purchasing process.” They are basically the rules the United States Government implements on just about anything it purchases. To do business with the federal government, you must have a basic knowledge of FAR and how to use it. In addition, we often see the DoD’s special add-on, DFARS (Defense Federal Acquisition Regulation Supplement).

In 1947 the FAR got its start in the form of the Armed Services Procurement Regulation. In 1984 the FAR was formally codified and created a uniform structure for federal government procurement. The purpose of FAR is to ensure purchasing procedures are standard, consistent, and conducted fairly and impartially.

The FAR is issued and maintained jointly by the Secretary of Defense, Administrator of General Services, and National Aeronautics and Space Administration. Procurement Executives in DOD, GSA, and NASA are authorized to make revisions. The entirety of the FAR is over 2000 pages and the DFARS are additional 1500 pages (for reference an average novel book is 300-400 pages).

The entire FAR does not apply to every order, instead, when the government procures an item; various sections are applied and then flown down. I will address a couple we often see and what the means to Nook.

48 CFR § 252.225-7008 - Restriction on Acquisition of Specialty Metals. Many of our corrosion-resistant (stainless) steels fall under this clause. When we procure our raw material at the very start of the process, it must be manufactured in the United States or a qualifying country.
48 CFR § 52.225-1/26 – Buy American. In short, the title says it all. The majority of the product must be made in America or a qualifying country. They list methods to calculate the amount of foreign material used as well as the allowable percentage.

Fortunately, Nook’s standard business practice allows us to be compliant with most aspects of the FAR without additional effort. However, there are thousands of pages and clauses that can be applied to an order. These can range from special metals to texting while driving, even to combating human trafficking. Should any of them appear on a purchase order or terms and conditions, the Nook team knows to flag them for a compliance review.

While the Federal Government has an abundance of rules and regulations, they do try to keep it high level. Rarely, will they define how to process a product. However, within each customer's flow downs things can start to get more restrictive. As prime contractors receive orders, more and more restrictions can apply through each sub-tier supplier. Some of the more frequent clauses we see at Nook are things like, Approved Supplier List, NADCAP, and Locked Process.

Approved Supplier List

Every company has its business system that it works within. Nook has its own Approved Supplier List or ASL. An ASL is comprised of suppliers the customer company has certified as capable of supplying a service or product. It is not uncommon to have a purchase order be received with the requirements to use suppliers as listed on the ASL. This is important to note upfront because it can affect how the part is manufactured and what outside vendors are used. While there can be overlap between Nook and our customer's ASL, it can often require setting up a new outside vendor, gathering pricing and lead-time quotes to be compliant.

NADCAP

Some of our customers allow or require NACAP suppliers in place of the ASL. National Aerospace and Defense Contractors Accreditation Program – NADCAP is a worldwide program designed to manage special process suppliers. These suppliers have been certified under NACAP accreditation. This process requires them to meet the industrial or governmental standard for the process they supply. This means that any NACAP supplier should process parts to the appropriate standard every time, making one NADCAP supplier interchangeable with another.

Locked Process

The ASL and NADCAP are designed to ensure the end product is produced the same time every time. This is all part of a Locked Process. To better understand this, we need to take a quick detour into how the government qualifies a program. Getting a new program into production with the government is not a quick process. Once the idea is put out for bid the prime contractors will start their proposal. This proposal can include early RFQ’s to many of the sub-tier suppliers including Nook.

Early quotes are considered if the program is feasible. Once development is approved, we will see initial orders for development. These orders aren’t always subject to the flow downs and requirements. They are proof of concept ideas to see if the program will function as designed. If the design works and moves to the next stage, we will see qualification units. It is not uncommon to see several rounds of qualification. Each sub tier wants to test and qualify their product. This continues until the end product is tested and qualified by the Federal Government for approval.

Even in accelerated programs, final qualifications can take years to reach. That is where the Lock Process comes into play. Once units start going into qualification, if they work, don’t change it. Location, machines, tooling, and sub-tier suppliers are all some of the items that must remain the same from qualification through production. Of course, the government isn’t unreasonable and understands things change over the years. Each change after qualification must go through an approval process before being implemented.

These are just a few of the common things we see in programs that come from government funding, it is by no means an all-inclusive list. Nook strives to supply the most cost-effective and quality product to its customers. As a company, we are well versed in helping meet the needs of any customer from an economical commercial solution to a certified and qualified government program.

Dan Piltz is a Nook Senior Design Engineer. He also specializes in managing the technical aspects of government projects.

Need Linear Motion Support for a Government Project?

Contact one of our experts for further assistance:

Electric Linear Actuators in Solar Trailers

Wed, 03 Mar 2021 13:33:27 -0500

Electric Linear Actuators in Solar Trailers

Solar trailers are stand-alone power systems that use solar technology to provide continuous and reliable power to remote site loads.

An alternative to traditional generators

As fuel prices climb, the efficiency and affordability of off-grid photovoltaic (PV) systems continue increase. This makes solar-electric power a competitive and smart alternative. The best fossil fuel generator may last several years; however a mobile solar generator can produce reliable power for 30 years and beyond. Solar trailers provide an environmentally friendly way of producing power, and can also be a valuable long-term investment.

Given many recent advances in solar panel technology, electric linear actuators have proven to be an excellent way to supply linear motion for solar tracking equipment. Solar technology produces power by means of photovoltaic solar panels. These panels are positioned outside in such a way as to absorb direct sunlight. To do this properly, it is crucial to adjust and move them to the optimal position.

The ideal fit for Solar Applications

Electric actuators are an ideal fit for powering green devices such as solar panels. An electric linear actuator works by converting an electric motor’s rotational motion into linear motion, giving a machine the ability to move in various directions (push and pull/up and down). They are a much more environmentally friendly (and more efficient) solution when compared to hydraulic systems.

Electric linear actuators can help improve the efficiency of the solar panel system by continuously (and accurately) positioning the panels to follow the orbit of the sun. As demand for solar power continues to increase, equipment designers are constantly exploring new vehicles for solar panels. This includes solar trailers - portable vehicles with solar panels attached to their roofs or platforms. These useful mobile machines harness the power of solar energy in various locations due to their easy portability.

Electric Linear Actuator

Mobile Solar Advantages

Solar Power is good for the environment while also benefitting for your wallet. They can power endless applications such as a job-site office trailer, remote LIDAR systems, isolated research stations, temporary accommodations, or a home during a grid outage. Other power sources (using fossil fuels) can be noisy, smelly, and rely on increasingly expensive energy sources.

Off-Grid Power

Solar trailers are easy to tow and set up. They provide a durable, cost-effective solution to off-grid power needs. As a bonus, they operate rely on massive energy banks to provide power through days of bad weather. And since some solar trailers are not attached to the ground, they shouldn’t require permits or inspections (and should not increase property taxes).

Clean: No exhaust. No carbon emissions. No oil changes.
Quiet: Crisp, distortion-free power. Highly valued at sites where communication is critical for safety.
Reliable: Their simple design provides low maintenance with increased reliability.
Affordable: Last longer, require less maintenance, and do not rely on increasingly expensive fuel.
Durable: Panels are designed to withstand the most brutal conditions (performing for decades).
Business Benefits: May qualify for a Federal or State Income Tax Credit.
Safe: Safe to any devices running off them.

Mobile Solar Project using Electric Cylinders

Nook Solutions for Mobile Solar Applications

Nook electric linear actuators and screw jacks offer affordable, custom-fitted solutions for high performance solar tracking including accurate positioning, rugged long life, and the ability to withstand harsh environmental conditions.

We provide several solutions for linear actuation on variety of solar applications, including trailers and mobile vehicles. For improved control and accuracy of motion, they can be customized with many different sensing and feedback options depending on your application requirements.

All Nook electric linear actuators and screw jacks can be equipped with a holding brake that eliminates back-driving with high levels of force (both crucial to effective high wind operation). Our electric actuators and screw jacks require little to no maintenance, making them ideal for solar panel applications. In addition, their small, retracted length saves space any mobile solar trailer or machine.

Advantages Include

Extreme Durability
Perform in Difficult Environments
Eco-Friendly
Highly Accurate Positioning
Low Weight and Compact Size (Space Saving)
Very Low Maintenance (Increased Throughput)
Sensing and Control Accessories to Monitor Performance

Nook Solar Products - “Safe, Rugged, and Reliable.”

The following is a selection of our products that are specifically designed to reliably perform in the extreme environments necessitated by solar applications.

Screw Jack - Double Clevis

Double Clevis Jacks are used when it is necessary to move a load through an arc, such as tracking antennas, hinged doors or air dampers. Machine Screw and Ball Screw Jacks from 1 ton to 15 ton capacities can be supplied with double clevis mounts. One clevis is mounted on the end of the lift shaft and the other clevis is welded to a heavy-duty stem cover, which is welded to the housing. Double clevis designs are available with optional accessories such as boots, motor mounts, right-angle reducers, motors, encoders, and rotary limit switches.

Electric Cylinder - Standard model thrust capacities from 500 lbs. to 40,000 lbs.

Electric Cylinders have been used on countless solar applications where performance in demanding environments is critical. They feature ground and hard chrome plated actuator tubes with industrial enamel paint on exterior surfaces. Available with ball screw and acme screw drives

Electric Cylinder in Solar Trailer

Programmable Linear Actuator

Nook Industries Programmable Linear Actuators are ruggedly designed for continuous duty, larger loads, long service life, and higher speeds. They incorporate a direct drive or toothed belt drive for high mechanical efficiency that allows for a quiet running performance. Programmable actuators are supplied with either a ball screw or acme screw, and either a servo or stepper drive system.

Get Help with a Solar Application

We have years of experience working with mobile battery-based photovoltaics and alternative energy sources. Contact us now and let us find a linear motion solution for your mobile solar generator that best suits your requirements and budget.

If you would like to learn more about how electric linear actuators can improve your mobile solar equipment, contact one of our liner motion experts.

Large Scale Linear Motion for Infrastructure

Thu, 04 Feb 2021 08:05:13 -0500

Moving America's Infrastructure

I think many people typically envision the size of a ball screw as something you can hold in your hand or carry around; or a screw jack lifting a vehicle or a load on a pallet. Nook has definitely been a driving force in smaller-scale applications in sectors such as aerospace, defense, and medical. In this case, we are using the terms "small and large scale" in reference to physical size of the application.

However, for decades Nook has also specialized in providing large-scale linear motion products for large-scale infrastructure projects. We routinely stock ball screw and acme screw lengths up to 24' in length. For custom projects, we have also completed several projects involving screw lengths in the 40' to 50' range.

Safety, reliability, and durability are absolutely critical in infrastructure applications. Therefore, it is essential to partner with an experienced linear motion provider that you can trust. We currently have many such projects flowing through our Cleveland, Ohio facility. Below you can see a few examples of large-scale linear motion products:

Large-Scale Machine Screw Jack and Ball Screw Assemblies

Typical Large-Scale Applications

Infrastructure is the set of fundamental facilities and systems used to support the functionality of a country, city, or critical industry. This is often comprised of facilities necessary for economic and industrial function. This includes (but is not limited to) public and private physical structures such as roads, railways, bridges, tunnels, water supply, sewers, electrical grids, and telecommunications (including internet connectivity).

There are endless applications for large scale linear motion, especially as we see more re-shoring (and upgrading) of facilities.

Oil & Gas
Airports
Shipping
Heavy Industrial
Construction (Roadways, Bridges, Hydro-electric)
Communications
Railways

And many more...

Other Applications

Other non-traditional applications for large-scale linear motion can include:

Sustainable Infrastructure (Solar, Water, Wind Energy)
Entertainment (Stadiums, Zoos, Amusement Parks)

Many of the improvement re-shoring and projects will focus on migrating away from hydraulic and pneumatics (where possible).

Need to move something BIG?

Nook can help... contact one of our linear motion experts regarding a specific application, or explore related products further.

Made in America

Contact a Linear Motion Expert

Explore Ball Screw

Explore Screw Jack

Electric Linear Actuators: Moving Modern Industry

Thu, 21 Jan 2021 11:03:40 -0500

New Website Section: Moving Modern Industry

Explore several automation fields that have been optimized by the endless versatility and dynamic performance Nook Electric Linear Actuators.

Reduced Footprint (multiple products on one line)
Increased Asset utilization (maintenance free operation)
Greater Throughput (faster speeds with high precision)

Learn More

Comparing Modular Linear Actuator Drive Types

Tue, 05 Jan 2021 10:42:16 -0500

Highly Specialized Linear Motion Based on Your Applications

With Nook's modular linear actuators, there are no limits in the variety of possible configurations. For several decades we have helped a huge number of customers with very special linear motion requests. Our customers receive customized solutions for a wide range of drive types and guides.

These modular linear actuators are found in virtually every area of the automation industry. Our customers value their performance in processes ranging from simple positioning tasks to highly complex multi-axis systems that require great precision.

Comparing Drive Types

There are typically four main drive types for these linear actuator systems. While there is some common functionality, each method can have several distinct advantages for a given individual application. We will explore each of the drive types in further detail here.

Belt Drive

Linear actuators with "toothed" belt drive are designed for high-speed motion over long distances. They are perfect for fast positioning and handling tasks involving light to heavy loads in which high repeat accuracy with short cycle times are also vital. The drive is provided via a steel-reinforced toothed belt.

With standard accessories, these linear axes are easily combined to create multi-axis systems. Our innovative technology keeps wear in the units to a minimum providing longer service life. They offer a much lower cost solution as compared to linear motors.

Explore Belt Drives Further

Screw Drive

Linear actuators with screw drive are preferred for high axial thrust forces, where the highest precision is also required. They offer a convenient and exact solution. Screw drive makes it possible to generate high feed forces and are particularly suitable where there are stringent requirements for positioning and repeat accuracy. You can choose between acme and ball screw types.

Acme screw or ball screw drive?

Acme screw drives are suitable for transferring large axial forces while providing a self-locking advantage. Nook acme thread linear actuators are long established standard in robust and precise applications.
Ball screw drives are particularly suitable for applications with increased precision requirements and are characterized by very high efficiency with very low friction. As a result, the breakaway torque and the drive torque are reduced to a minimum.

Explore Screw Drives Further

Rack & Pinion Drive

Linear actuators with rack and pinion drives are used for highly dynamic movements with long distances. Even with heavy loads, they offer constant positioning accuracy. They also provide greater feed forces in long strokes. This solution gives you high stiffness, excellent positioning accuracy, and high load capacity.

The racks and the rack wheels deliver a very long service life. Any number of rack segments can be connected together, allowing unlimited lengths. Furthermore, several carriages can be operated independently of each other on the linear unit (saves time while increasing throughput).

Explore Rack & Pinion Drives Further

Linear Motor Drive

Linear actuators with linear motor drive are particularly suitable for applications with high accelerations and speeds, where high precision is required with a low load. The carriage is propelled into a linear movement by a flat electric motor. As a result, these linear units boast lower space requirements and, at the same time, offer several advantages over other drive types.

In addition to its outstanding dynamic performance and precision, the compact system is low noise, low wear, and low maintenance. At the same time, you minimize maintenance-related downtimes and drive-induced failures. They are a much higher cost solution as compared to the other alternatives.

Need help with a linear motion design?

Get help with an application

Specialized Paint, Coatings & Materials for Demanding Environments

Mon, 23 Nov 2020 12:09:06 -0500

Lining Up for Duty Under Extreme Conditions!

These half ton ball screw jacks will soon be deployed for heavy duty use in a demanding outdoor application. Before shipment, they will receive special grade paint to optimize their performance under those harsh conditions. Nook has specialized in-house capability to manage specialized paint, coatings and materials for our screw jack, electric cylinder, and linear actuator product lines.

This is another distinct advantage of having all of operations co-located at one U.S. based facility. This provides us with the nimbleness to easily coordinate customized solutions that give your equipment an advantage under extreme conditions. Our advanced paint cell does this every day.

Demanding Environments Can Include:

Excessive Heat and Humidity
Extreme Cold and Ice
Water
Dust and Dirt
Food Handling
Corrosion

Sizing Up the Application

First, it is important to consider your specific requirements for performance, budget, and schedule.

A good place to start…

A good first step is to determine where your application falls on the standard Ingress Protection Ratings Guide.

Where does the application fit on the IP Ratings Guide?
What level of protection is actually required?

Additional detail...Once there is a basic understand of the required protection level, we can now further determine some other specific environmental requirements such as:

What are the budgetary and schedule restrictions?
What is the operating environment (heat, cold, wet, dry, dirty, etc...)
Does the application come into contact with food?
Are there any specific regulatory standards?
What are some key safety concerns?

Tailoring a Perfect Linear Motion Solution for Specific Environments

Once we have this basic application information, Nook can then match the ideal product fit with the right configuration and features to match the desired performance. In addition, we can align the right solution based to meet your budget and schedule limitations.

Below is an example where we were able to provide a custom solution for a tight budget. IP69K protection was not necessary for this particular food grade application. We are able to provide a lower cost solution to get the job done with limited investment.

Lower cost programmable linear actuator solution for food washdown application included:

2 Part white epoxy
Food grade top coat
Protect from wash down
Special gaskets/seals
2nd plate with rod/wiper
Special motor mount

Standard Linear Actuator

Customized Version

Get Help with an Application

Premium Finishes

Premium finishes are available including Epoxy, Outdoor, Marine, or any other finish or coatings per customer specification.

Understanding your environmental condition is critical to any successful application. To maximize life of any Nook Industries products, considering material and paint options is critical depending on the operating environment. Many of our products can be offered in anti-corrosion material, such as 304 stainless alloys. In addition, Nook Industries provides several paint options for a variety of environmental applications.

We can also paint or apply specialized coatings to a specific customer specification.

Some examples of a few basic paint alternatives:

Other Specialized Environmental Components

Nook provides a host of options designed to enhance environmental performance. Some of these include:

Stainless Steel Worm Shafts
Chrome Plating
Stainless Steel Fittings and Hardware
Specialized Seals
Low Temperature or High Temperature Grease
Bellows Boots

Nook has the solutions to optimize performance in any demanding environment.

Stainless Solutions

Nook also provides a variety of stainless steel options that are ideal for use in environments that are wet, humid, or provide exposure to contaminants such as industrial strength cleaning solutions or harsh chemicals.

Screw Jacks

Modular Linear Actuators

Food Grade Linear Actuators

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10 Benefits of Reshoring Manufacturing to the U.S.A.

Thu, 05 Nov 2020 11:01:21 -0500

A Heightened Focus on Reshoring

Over the last few decades, many companies across all industries have invested significant effort and cost to offshore the manufacturing of their products to countries with more attractive wages. In addition, these countries are relatively loose in their regulations. This made it easier to manufacture with flexibility and increase profits further.

The costs and risks of lengthy supply chains have been exposed in the wake of the COVID-19 pandemic. This is driving more companies to consider reshoring their overseas operations to the United States.

Reshoring includes not only relocating existing manufacturing back to the United States, but also new investment in domestic plants that might have gone overseas.

Not Just Medical Supplies

The supply chain disruptions experienced during the pandemic will impact future business decisions across a variety of market segments. This trend is beginning to extend beyond medical to other industries. This includes electronics, aerospace, automotive, defense and consumer products.

Benefits of Reshoring

1. Comprehensive Quality Control

Quality is a critical consideration for most manufacturers. However, it is especially critical for high technology industries such as medical, aerospace, transportation, and defense. It is much easier to manage the quality of suppliers when they are in the same region as a manufacturer.

Closer is better for communication and management of critical to quality parameters. In addition, regions with more mature and established regulatory systems generally create higher quality products as a benefit of more stringent oversight.

2. Significantly Streamlined Logistics

It is much easier to control and manage inventory when it is not tied up in the many forms of transit and storage. Waiting to make changes or upgrades to a product once it arrives (as opposed to on the fly), often times causes major delays in lead time. In addition, there are obviously much lower shipping costs without all of the red tape associated with international transport.

3. Availability of Skilled Workforce

The United States has millions of talented, highly skilled workers throughout the country. This has historically been a strong juggernaut for innovation and that trend will assuredly continue as more manufacturing is brought back (innovation and manufacturing typically have a strong correlation).

4. More Effective Facility Management

Companies with overseas facilities often encounter a variety of discrete costs, risks, and organizational challenges associated with a remote footprint. Improvements and updates to processes or systems can be very tricky when implemented at different locations by individual teams. General oversight is simplified, and costs are reduced when visiting a different part of a building versus travelling to different part of the world.

5. Simplified and More Efficient Supply Chain

Components for end products that originate from local suppliers greatly increase the overall efficiency of supply chain management. It is also beneficial to collaborate with suppliers in a region that share similar business philosophies (Including quality management systems). It is much more efficient to collaborate with a team in a similar time zone (a few hours as opposed to 12). This also eliminates many of the language barriers that can sometimes exacerbate issues.

6. Local Manufacturing Fosters U.S Innovation

Innovation has historically gone hand-in-hand with manufacturing. Having U.S. citizens actively engaged in the process of manufacturing will inherently drive new inventions that naturally occur from this process.

7. More Americans Participate in the Economy

Returning manufacturing to the United States will also help offset millions of lost jobs as a result of the COVID-19 stay-at-home orders. While it is expected that good numbers will return to work as order is restored, certainly many will not. A larger percentage of employed Americans will significantly benefit all segments and industries. Everyone wins when more of us are actively participating in the economy together.

8. Avoiding Expensive and Complex Taxes/Tariffs

Initially, many companies were willing to absorb the higher tariff costs, however this surely not the best long-term option. Eventually, these higher tariff charges must be passed on to the end customer. Ultimately, this will result in lost market share for many product-based businesses.

9. Intellectual Property Protection

Intellectual property is not fully protected in the same manner globally as it is in the United States. The protections in the United States and Europe are far superior to those in many other parts of the world. Having sound and organized legal recourse is an ideal option in a situation when your IP is stolen.

10. Simplified Legal Issues

The legal system can be extremely beneficial for long-term stability in all areas of a business. Managing multiple legal systems (across different countries) is significantly more challenging. Certification for countries outside of the United States is generally much easier to obtain using U.S. based labs and institutions.

High-quality components are a cornerstone of a high-quality assembly.

Nook is your trusted onshore resource for linear motion solutions.

All of our operations are co-located in one U.S. based facility. In addition, we have a vertically integrated supply chain that provides you with unmatched flexibility, quality, and service.

Our supply chain is fully engaged to integrate with your supply chain.

Made in USA

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Miniature Ball Screws: Big Efficiency in a Small Package

Wed, 21 Oct 2020 13:26:53 -0400

Perfect fit for Aerospace & Medical

Miniature Metric Precision Ball Screws provide an efficient, cost-effective linear motion solution in a small package. This makes them ideal for use in applications where space is limited (driving a compact design) and highly efficient motion is required.

There is no industry standard that classifies a ball screw as “miniature". However, most manufacturers apply the designation to ball screws with a diameter less than 16 mm. The leads for these ball screw assemblies typically fall within a range of 1 to 20mm. Ball screws with a diameter of 6mm or less are sometimes referred to as “sub-miniature”.

Miniature Metric Ball Screws: Typical Market Segments:

Medical
Aerospace & Defense
Semiconductor
Optical
Test & Measurement

Miniature Ball Screws are a highly efficient means (>90%) of converting rotary motion into linear motion. This gives them a distinct advantage over other lead screw devices (typically <50%) when efficiency is crucial to a given linear motion application.

Not to be Confused with "Compact"

Miniature ball screw should not be confused with “compact” versions that many manufacturers typically offer. The term "compact" generally indicates a cylindrical ball nut with internal recirculation. This provides the nut with smaller ("compact") outer diameter. The ball nut diameter has a compact design; however, they are often paired with much larger diameter ball screws.

Similarities with Standard Ball Screws

In some cases, miniature ball screws are similar to the larger “standard” sized versions. As an example, they share many of the same ball nut options including standard, flanged, cylindrical, or threaded. Ball recirculation methods are also similar in design (internal or external). Lead accuracy and preload classes follow the same designations regardless of the screw diameter. And design parameters such as life, load, and critical speed are the same.

Advantages and Differences

in addition to a smaller footprint, miniature ball screws offer an advantage over standard versions due to their very fine leads. This is a significant benefit in applications that require fine adjustments and micro-positioning.

Miniature ball screws utilize very small balls for load carrying. This limits their preloading over traditional sized ball screws (typically 3% difference). However, miniature ball screws can provide more customization flexibility.

Miniature ball screws are typically constructed of stainless steel material because they are used to carry much smaller loads. Stainless steel is less capable of handling heavy loads (unlike standard ball screw material).

Nook Miniature Ball Screws

The Nook Miniature Ball Screw Product Line consists of different offerings in a wide variety of sizes and configurations. Our miniature product line is supplied as a complete assembly. Screw ends can be machined to customer requirements in nearly any diameter and length configuration.

We offer larger sized Precision Metric Ball Screws (PMBS) and a full line of Miniature Metric Ball Screws.

Miniature Ball Screws

PMBS & Miniature Ball Screw Literature

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Electric Cylinder Application: Foundry Automation

Mon, 12 Oct 2020 12:45:02 -0400

These heavy duty electric cylinders will optimize the linear motion of equipment used in the Metal Casting Industry.

Casting Automation Equipment

The massive shift from iron to aluminum and other light alloys (driven by both ecological and economical reasons) is impacting affecting the future design of metal casting equipment. As a result, foundries are investing heavily in advanced machines and systems.

This is primarily driven by the ever-increasing aluminum content in vehicles (~5% annually). To meet this growing demand, a large number of foundries will be required throughout the world.

A wide range of equipment and systems are available that can automate common tasks while improving overall casting output. The decreasing cost of automation systems, and increased competition is allowing even smaller facilities to shift towards more automation.

Cost reduction, product quality, and consistency are among the primary reasons metal casters are converting to automation systems. Robotics provide increased ergonomic benefits while taking on more dangerous activities such as pouring (improving safety).

Types of Foundry Automation include:

Removals & pick off systems
Automated casting, cleaning, and inspection stations
Automated sting, pouring and coating stations
Robotic cells and handling systems

Advantages

The primary advantage of using automation systems in foundries is flexibility - they readily adapt to a variety of tasks and functions.

Reduced cost and streamlined production processes
Greater consistency and improved productivity
Reduced scrap castings and improved worker safety.

Nook Electric Cylinders - The ideal complement to Heavy Industrial Automation Equipment

Electric Cylinder

Nook’s rugged Electric Cylinders are available in standard models with thrust capacities from 500 lbs. To 40,000 lbs. Electric Cylinders are intended for heavy duty use in industrial environments including outdoor applications.

They are supplied in a Single Reduction, Double Reduction, or an In-Line Configurations. Electric Cylinders are intended for use in industrial environments and feature ground and hard chrome plated actuator tubes with industrial enamel paint on exterior surfaces. Heavy duty electric cylinders can be supplied for outdoor applications.

Use individually or in multiple arrangements.
Built to specification.
For outdoor applications, contact Nook Engineering for recommended alterations.
Ground and hard chrome plated actuator tubes.
Exterior surfaces feature industrial enamel paint (Epoxy, polyurethane, and marine grades available on request).

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Ball Screw Application: Precision Machining

Thu, 24 Sep 2020 11:09:03 -0400

Precision machining continues to remain a highly essential technology for creating components of the many items we depend on each and every day. Here we take a closer look at precision machining and how Nook ball screw assemblies are ideal for supporting advances in this modern manufacturing technology.

What is Precision Machining?

Precision machining is a type of technical manufacturing that is essential in creating and designing machines, parts, tools, and other hardware using process controls and tolerances, that function under extremely tight specifications.

Precision machining creates parts according to tight tolerances so they fit precisely into the object or machine they are made for. If an object consists of many small parts, it will often require precision machining to ensure proper fit and function. Because precision machining requires extreme accuracy, the materials and machining equipment must be very specific.

Precision machining has evolved over time, and technology advancements continue to push the limits of performance. Precision machining typically combines computer-controlled design and human engineered design to create unique features. Precision machining is important to create parts with precision, stability, and repeatability with consistency, accuracy, and durability.

How it is used

Precision machining can be used to create a wide variety of parts from any number of different materials. These parts usually require tight tolerances and minimal part-to-part variation from nominal dimensions. This translates into very tight margins for error in production. Repeatability and well-controlled tolerances are hallmarks of precision machining.

How it works

Precision machining is a subtractive process where custom software, engineered tools, and process steps are utilized on raw material such as plastic, ceramic, metal, or composites to create desired fine-featured products. Precision machining is often controlled by computer aided design (CAD) and computer aided manufacturing (CAM) programs. These programs enhance the ability to meet tight tolerances. However, while most designs end up as computer aided designs, they often start out as hand drawn sketches.

Tools and Materials

Precision machining can utilize a variety of raw materials including (but not limited to) plastic, ceramic, metal, composites, steel, bronze, graphite, and glass. In order to make precise cuts and intricate material removal, a combination of tools may be used. CNC heavy machinery is commonly used to remove substrate material to create finely detailed components. In some cases, high-speed robotics may also be used.

Swiss Machines: Provide accurate and precise function according to specific CNC encoded instructions (computer numerical control). Originally used to create parts for Swiss watches, they are very effective at machining small parts without displacement or vibration. They hold the workpiece in place, while the tool rotates around it.

Lathes: Rotates the workpiece against a cutting tool. They can also be controlled by a computer to produce intricate designs. They are ideal for products that are symmetric around an axis of rotation. Different types include - turret lathes, engine lathes, and special purpose lathes.

Mills: Uses rotating cutters to remove material. Often feature moveable tables on which the workpieces are mounted. The cutting tools are stationary, and the table moves the material to make the desired cuts. Operations include planing, cutting, rabbeting, routing, and die-sinking.

ECM/EDM: Electrical Discharge Machine are used to cut metals that are electrically conductive. Uses an electrically charged wire or electrode to cut or punch metal.

Laser Engraving: A laser on a rotary attachment provides functionality for etching or engraving. Laser engraving is essential for logos, serialization, and QR codes imprinting.

Grinding: Use an abrasive wheel to create fine finishes/faint cuts. The wheel or product is moved from side to side to create the desired finish. Types include belt, bench, cylindrical, surface and jig.

Sawing: Sawing of metals is generally performed using cut-off machines. Other machines include power hack saws, abrasive wheel saws, and circular saws.

Broaching: Used to produce square holes, keyways, spline holes, etc. It consists of many teeth arranged sequentially a with each tooth slightly larger than each previous tooth.

Drilling/Boring/Reaming: Drilling produces cylindrical holes in solid materials using drill bits.

Learn More about Precision Machining

Use precision components in your precision equipment.

Our operations are all located at a single U.S. facility in Cleveland, Ohio. This gives us tremendous flexibility to manage our supply chain while increasing the efficiency and performance of your machines. We accomplish this with a rigorously controlled process integrity that includes Lean Manufacturing, 5S, and Six Sigma. Our Quality systems emphasize continuous improvement, defect prevention, statistical methods and ongoing training to increase the knowledge and skills of all employees.

Nook Industries can not only manufacture build to print solutions for a customer's design, we also have the extended ability to Develop, Evaluate, Optimize, and Validate a custom design. Nook provides a wide variety of testing and simulation services to help our customers design better products. We can simulate many real-world scenarios to determine how a given design will perform. This helps to speed design process, improve reliability, determine life cycle, and predict performance in advance.

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Advanced Testing and Simulation Capabilities

Wed, 09 Sep 2020 09:37:49 -0400

Nook Industries can not only manufacture build to print solutions for a customer's design, but we also have the extended ability to Evaluate, Optimize, and Validate a custom design.

Nook provides a wide variety of testing and simulation services to help our customers design better products. We can simulate many real-world scenarios to determine how a given design will perform. This helps to speed design process, improve reliability, determine life cycle, and predict performance in advance.

We apply solid modeling and finite-element analysis (FEA), as well as industry best practices such as tolerance analysis, risk analysis, and comprehensive testing protocols to ensure all products perform to exact requirements. Design and process verification/validation tools are employed throughout the product development cycle.

Nook's engineering team is trained and experienced in designing and evaluating solutions for some of the harshest conditions across multiple industries, including Nuclear, Defense, and Aerospace.

Life testing with predictive tools, data for prognostics, performance wear models, and proof testing under multiple operating conditions helps to reduce design cycles.

Design Optimization and Validation

Nook utilizes traditional calculations paired with Solidworks™ Simulation to perform upfront component and system evaluation. This allows the design to be optimized before parts are released for manufacturing. Ultimately, this predictive modeling helps to avoid costly design issues from appearing further into the program schedule.

Other simulation software such as MESYS is utilized to optimize ball screw performance. The Nook engineering team can evaluate and optimize performance from the total system down to the individual ball bearing used.

Nook Industries can see a design through from initial design optimization to final design validation based on the customer's individual needs. From efficiency testing to life validation, we can design, test, and validate linear motion systems from beginning of the development cycle to product release.

Nook Simulation and Testing Capabilities

Design Validation Testing

Life Testing
Loading Testing
Efficiency Testing
Functional Testing

Simulation Analysis

Linear Static Analysis
Nonlinear Static Analysis
Frequency Analysis
Thermal Analysis
Random Vibration Analysis
Nonlinear Dynamic Analysis: impact, shock, time
Varying Loads
Design Study (Parametric Optimization)
Fatigue Analysis
Linear Buckling Analysis
Drop-Test Analysis

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Evolving Planetary Roller Screw Applications

Thu, 27 Aug 2020 09:02:35 -0400

Evolving Applications for Planetary Roller Screws

Planetary roller screws are being used in an ever-increasing range of applications in various industries. Evolving market segments include electric aircraft, electric vehicles, robotics, industrial automation, and the oil and gas industry.

Aerospace
Automotive
Oil and Gas
Machine Tool and Fabrication

However, the fastest growing segment involves electric vehicles and aircraft. In the automotive and aerospace sectors, planetary roller screws are often used to enhance efficiency of embedded applications such as flight control and vehicle control sub systems. This trend should continue over the next several years as demand for electric-powered trucks, cars, and aircraft continues to escalate.

In addition to the vehicles themselves, OEM's will require optimized manufacturing capability to produce them. Specific automated process operations include:

Pressing and Inserting
Robotics
Welding Guns
Paint Sprayers
Precision Machining Equipment

Automated industrial systems, assembly cells, and production lines continue to get smaller. As a result, manufacturers are continuing to develop more compact systems that save facility floor space. OEM's are relying more on automated industrial systems to enhance product performance and optimize manufacturing process efficiency. Specific requirements include greater reliability, lower power consumption and increased precision. As a result, Planetary Roller screws are widely used in automated applications for various operations requiring high levels of repeatability and accurate linear motion.

Delivering the highest level of performance.

Planetary Roller Screws transform rotary motion into linear movement. The rolling elements consist of threaded rods which enable excellent force density, very high load capacities, and long life. Planetary roller screws provide high levels of load, speed, and duty cycle. In addition, they offer:

High Axial Rigidity
Outstanding Positioning Accuracy
Mechanical Repeatability
Low Sensitivity to Contamination
Long Life Cycle
Low Maintenance
Fast Acceleration

Due to the increase in contacts point compared to ball screws, roller screws have significantly increased dynamic load capacity (within the same size package). This contributes to a much higher life span and dramatically increased static load capacities. The increased contact points also enable stronger rigidity a much higher tolerance to shock and stress. This makes them ideal for applications that require continuous stressing.

Planetary Roller screws assemblies require very little maintenance when compared to hydraulic and pneumatic systems. There are no recycled ball bearings with roller screws. Thus, they can handle much higher rotational speeds (with faster acceleration).

Cutting edge industrial automation machines require increased positional accuracy at higher speeds. In some applications, traditional linear screw technologies may not be ideal for the challenging application. Planetary roller screws are the most optimal choice in applications where precision and reliability cannot be sacrificed. If a ball screw design falls short, then a planetary roller screw should be considered.

Knowing the basics of their anatomy and specifications can help to determine if roller screws are the right solution for your application.

The cost benefit of these electromechanical systems provides significant return on investment with less power consumption, smaller footprint, low maintenance and very long service life. By adding an electric motor, they can easily be retrofitted as a drop-in replacement for pneumatics or hydraulics.

Nook Planetary Roller Screws (NRS), a member of the lead screw family, are remarkable devices designed to convert rotary motion into axial force or vice versa. They offer multiple advantages and reliability for the most demanding applications due to their:

High efficiency rolling motion even in relatively shallow lead designs.
Multiple contact points that carry large loads and with very high resolution (small axial movement) when using very shallow leads.
High rotational speeds with faster acceleration without adverse effects.

Specifications

Diameters – 8 to 75mm (.31 to 2.95″)
Leads – 2 to 42mm (.079 to 1.65″)
Precision Lead accuracy – IOS 5 (standard) ISO 3 & ISO 1
Materials – Medium carbon induction hardened alloy steel screws and High Grade bearing steel rollers should be specified
Nut Styles – Split or one-piece solid nuts in a cylindrical or flanged style

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Planetary Roller Screws

Ball Screw Design - Safety Considerations

Fri, 14 Aug 2020 15:07:57 -0400

Designing Safer Ball Screw Assemblies

Ball screws provide several unique benefits when compared to other standards, such as roller screws or acme screws. Just a few of these include:

High Efficiency: Ball screws typically operate at a minimum of 90% efficiency. This makes them an optimal choice in converting rotary motion into precision linear motion.
Load Capabilities: Ball screws are highly versatile in so many industries and applications because they can carry remarkably heavy loads at fast, efficient speeds.
Cost-Effectiveness: In the long run, ball screw systems are a more cost-effective alternative to pneumatic or hydraulic systems, which require constant power, hoses, fluids, etc...

However, there are some very important safety factors to consider when designing a given ball screw assembly for your applications. These factors can also provide longer life and more reliable performance. There are several factors conducive premature ball nut failure, such as misalignment, impact loading, a lack of lubrication, contamination, or external damage to the return circuits. However, the primary failure mode for ball nuts is fatigue of the bearing balls or thread surface.

Premature failure may result in the loss of some or all of the balls between the nut and screw. When all the balls are lost, the nut is no longer engaged with the screw and therefore may not move when the screw is rotated or, in vertical applications, will free fall along the screw. Let's look at some of the typical failure modes below.

Typical premature failure modes

Misalignment of the ball nut to the screw can result in undesired side loading or eccentric loading. Both of these will reduce life. Additionally, this may cause the ball bearings to split or get flats on them. Additionally, the ball bearings may even break out of the return tubes.
Metal chips, dirt or debris in the ball nut may impede the call bearings from free circulation. The ball bearings may get flats on them because of skidding,
Lack of lubrication. Proper lubrication will help to dissipate heat and reduce metal-to-metal wear of components.
Exceeding the ball nut critical speed can break pickup fingers off, causing the balls to come out of the nut. Exceeding the screw critical speed will also cause the whip resulting in misalignment.

In some applications, this loss of ball type failure could result in injury or even death. Therefore, this failure needs to be considered in the design to assure proper safety.

Possible preventative measures include

Using two or more screws supporting the load.
Nuts with multiple independent ball re-circulation circuits.
Ball deflectors which prevent the balls from exiting the ball nut out the ends.
Using industry-leading integral safety thread ball nuts.

The integral safety thread is a unique solution that provides the ball nut with a secondary safety thread (a reverse thread in the nut body itself). This special thread extends from the ID of the nut to below the OD of the screw without making contact. In the unlikely event that all the balls in the nut are lost, this safety thread will engage the screw and prevent free fall.

Although this thread can be used to lower the load to a safe position, it is should not be used otherwise. This can also be accomplished with the use of a special flange if the ball nut body cannot accommodate the safety thread feature.

Nook ball screw design are the safest in the marketplace. All manufacturing operations are tightly controlled in one facility using demanding standards.

Quick Reference

Screw	Helix	Safety Thread	Ball Deflector
0631-0200	RH	SBN10583	-
1500-0500	RH	SBN10974	-
2250-0500	RH	SBN10629	SBN10074
2250-0500	LH	-	SBN10075
2250-1000	RH	-	SBN10260
3000-0660	RH	SBN10202	SBN10202
3000-0660	LH	-	SBN10257
3000-1500	RH	-	SBN4986
4000-1000	RH	SBN3258	SBN3258

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Ball Screw Home Page

Selecting Linear Actuators for Robotics

Mon, 20 Jul 2020 16:52:28 -0400

Primary considerations for selecting electric linear actuators when designing robotics

Linear Actuators with complex multi-axis systems are proving to be indispensable in today’s continuously evolving industrial automation world.

These systems are highly effective in positioning, handling, and transporting components quickly and reliably. Some of the many applications for linear actuator systems include machine tool, welding, painting, assembly, picking and packaging operations.

To ensure machine designers can continue to meet the complex challenges of their end customers, it is important to select the proper linear actuator technology that best satisfies the application's requirements. We will explore each of these in more detail below.

Equipment developers should also select the highest quality components while collaborating with an experienced linear motion design team that specializes in projects involving customized linear axis systems. This will ultimately ensure an optimal cost Vs. performance return on investment by increasing flexibility and productivity while reducing down times.

Part Handling System in Workflow

Highly flexible integration is a primary characteristic of fully automated systems that align with the challenging demands of Industry 4.0. The includes combining multiple work steps within a small space while making the work cycle as fast as possible. In addition, it is critical to have the ability to readjust the workspace as the product requirements continue to evolve.

Robots on Rails

The robotic range of motion can be increased to provide more time for additional tasks within a given work cycle. This is accomplished by mounting the robot to a linear actuator rail system that moves the robot back and forth. As a result, the work area can now be designed with more flexibility to allow the integration of other tasks.

Robots on the seventh axis: Toothed belt linear axes provide the robustness and positioning precision necessary for this application. A good linear actuator system will provide a broad solution space, allowing the linear axes to be precisely adjusted to both the robot and production environment. Key factors include precision, load capacity, drive stiffness and smooth/reliable rail operation.

Multi-axis electric linear actuators provide robotics with the increased freedom of movement by removing the limitations of a fixed operating position (allowing them to move in multiple directions). This significantly increases the overall productivity of a robotic system.

Selecting a Linear Actuator for Robotics

Let's identify the some of the commonly used devices for robotic applications. There are different categories of robotic linear actuators. Robotic actuators are classified based on their ability (energy) to move a motor output shaft. Linear Actuators will only move in a linear fashion, while Rotary Actuators only rotate in an axis.

Motor Types

Stepper Motors - DC motors that move in discrete steps. They utilize multiple sets of coils arranged in groups or “phases“. The motor will rotate or "step" as each phase is sequentially triggered. Stepper motors are typically used when high precision in movement is required.

DC Motors - The output shaft spins when a DC voltage is applied across the motor terminals. Motor shaft speed is adjusted based on the magnitude of this voltage.

Servo Motors - Consist of a DC motor, gear system, and control unit. The control unit rotates the gear shaft with a specific angle based on PWN signals sent from the robot's computer. There both analog servos and digital servo types. Smart digital servos are now available in the market that provide position, speed, torque, and temperature feedback.

DC Gearbox - Adding a gearbox to a DC motor increases the shaft torque while reducing the motor speed. They consist of a DC motor attached with a gear system with an output shaft.

Electric Actuator with Motor Gearbox

Linear Actuator Types

Hydraulic Actuators - Typically used in handling heavy loads. They can produce very high force in comparison to other actuators. The chamber is filled with hydraulic fluid. Pressure applied to the fluid pushes the piston (moving the output shaft).
- Advantages: Easy to Control, Fairly Accurate, Constant Force (regardless of speed change), Low Noise
- Disadvantages: Messy Maintenance, Expensive, Fluid Leakage not Environmentally Friendly

Pneumatic Actuators - Similar to hydraulic actuators, however, they use compressed air to move the piston.
- Advantages: Less Environmental Pollution (Cleaner), Inexpensive, Safe and Easy Operation
- Disadvantages: Loud Noise, Less Accurate, Sensitive to Vibration

Electric Actuators - The most commonly used linear actuators in robotics. They convert electric energy into linear motion. There are AC and DC actuators, however most robotic applications utilize DC linear actuators.
- Advantages: The highest precision, easy to network and program, immediate feedback for diagnostics, complete motion profile control using encoders (velocity/position/torque), less noises, no fluid leak (environmentally friendly)
- Disadvantages: Higher Initial Cost (But lower overall cost of ownership)

Automated Pick and Place System

Modular Linear Actuators

Increased Flexibility and Faster Cycle Times for Robotics

Electric Modular Linear Actuators allow provide industrial robots with the ability to reliably execute highly automated motion sequences at a consistently high level of accuracy and speed. Servo-driven modular linear actuators can be integrated into high-performance automation systems for multi-axis-coordinated motion control.

Modular linear actuators foster easy Industry 4.0 "compatibility" and align well with the growing e-mobility market. These electric linear actuator systems provide machine developers with customized drive technology that fits seamlessly into their ever-changing designs. The modular built-in axes make it much easier to modify or convert machines later as requirements change down the road. In addition to footprint flexibility, synchronization, and work step transition are also much easier.

System designers can optimize the linear axes based on each individual application. For example, they can be specially optimized as a Z axis or customized as X and Y axes. This high degree of vertical integration makes it possible to build linear axes for manufacturing lines that best optimize the available space, while also saving energy and material.

Modular Linear Actuators

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8 Design Considerations for Screw Jack Systems

Fri, 10 Jul 2020 14:36:02 -0400

8 Design Factors to Consider

Regardless of the type of worm gear jack you are considering (machine screw or ball screw), there are 8 factors that are critical for developing the optimal linear motion system. In this post, we will examine these design constraints and how they can impact proper sizing, placement, and configuration of your screw jack system.

1. Load Capacity

The load capacity of the jack is limited by the physical constraints of the components including the drive sleeve, lift shaft, bearings. All types of anticipated loads must be calculated properly so they meet the rated capacity of the jack. These loads can include static, dynamic, moving, acceleration/deceleration loads as well as cutting and other reactionary forces.

It is critical that your design also accommodates shock loads. For optimal performance, these should not exceed the rated capacity of the jack.
To accommodate accidental overloads, screw jacks can sustain the following overload conditions without damage: 10% for dynamic loads, 30% for static.

2. Duty Cycle

Duty cycle is the percentage of "time on" as opposed to "total time". The largest determining factor in calculating duty cycle is the ability of the screw jack to dissipate heat that builds up during operation. As the generated heat increases or decreases, the duty cycle will also be impacted accordingly. Additionally, screw jacks may be limited by their maximum operating temperature (200°F) and not duty cycle.

The recommended duty cycles for screw jacks at max horsepower are:

Ball screw jacks 35% (65% off)
Machine screw jacks 25% (75% off)

Ball Screw Jack

3. Horsepower Ratings

Horsepower values are influenced by many application-specific variables including mounting, environment, duty cycle and lubrication. The best way to determine whether performance is within horsepower limits is to measure the jack temperature (Housing temperature near worm must not exceed 200°F.

The horsepower limit of a jack is a result of the ability to dissipate the heat generated from the inefficiencies of its components, based on intermittent operation.

Special consideration should be given for multiple jack arrangements, as total horsepower required depends on horsepower per jack, number of jacks, the efficiency of the gear box or boxes and the efficiency of the arrangement.

If the required screw jack maximum horsepower is exceeded:

Use a larger screw jack size
Consider a Ball Screw Jack (as a Machine Screw Jack alternative)
Decrease the input speed
Use a right angle reducer

4. Column Strength

Column Strength is the ability of the lift shaft to hold compressive loads without buckling. With longer screw lengths, column strength can be substantially lower than nominal jack capacity. If the lift shaft is in tension only, the screw jack travel is limited by the available screw material or by the critical speed of the screw.

If there is any possibility for the lift shaft to go into compression, the application should be sized accordingly. Designers should also be aware of effects of side loading. Screw jacks operating horizontally with long lift shafts can experience bending from the weight of the screw.

If the maximum column strength is exceeded:

Change the jack configuration to put the shaft in tension
Use a larger screw jack size
Add a bearing mount for rotating jacks
Change the lift shaft mounting (Ex: from clevis to top plate)

Machine Screw Jack

5. Critical Speed

The speed that excites the natural frequency of the screw is referred to as the critical speed. Critical speed varies with the diameter, unsupported length, end fixity and rpm of the screw.

Due to the nature of most screw jack applications, critical speed is often overlooked. However, with longer travels, it should be a major factor in determining the appropriate size jack.

Since critical speed can also be affected by the shaft straightness and assembly alignment, it is recommended that the maximum speed be limited to 80% of the calculated critical speed.

6. Type of Guidance

All linear motion systems require both thrust & guidance. Worm gear jacks are designed to provide thrust only and a guidance system should be designed to absorb all loads other than thrust. Preferred systems include hardened ground round shafting or square profile rail.

7. Brakemotor Sizing

For proper safety, a brakemotor is recommended for worm gear jack screws where the possibility of injury exists. Horsepower requirements will determine the size of the motor, and assure the standard brake has sufficient torque to both stop and hold the load.

High lead ball screws may require larger, nonstandard brakes to stop the load, to ensure against excessive “drift” when stopping.

Stainless Steel Jack

8. Ball Screw Life

A major benefit of the use of ball screw jacks is the ability to predict the theoretical life of the ball screw. Most major manufacturers will provide life charts for their products.

Once these factors are fully understood and considered, they can optimize the features and benefits of Machine Screw Jacks and Ball Screw Jacks. This ultimately makes selecting the right screw jack for your application considerably easier.

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3 Quick Screw Jack Applications - Food Industry

Mon, 29 Jun 2020 15:59:49 -0400

Screw Jacks and Food Processing

It's time for the annual 4th of July barbecue season. As we all prepare for the upcoming weekend festivities, I also can't help thinking about ActionJac™ screws jacks and the many uses they have in the food industry. Screw jacks have definitely served their purpose in the industrial sector over the years with many different types of factory applications. The same goes for the transportation segment in manufacturing, service, and ultimately the vehicles themselves.

There have been some interesting linear motion technical innovations designed to serve the food segment in recent years. But, many of the emerging food applications are still perfect for the venerable screw jack. It's simple yet effective design is timeless and it is a true work horse for food applications.

In the food sector, screw jack systems are typically deployed in three common and versatile arrangements. Let's talk about a few of these in more detail.

"U" Arrangements

“U” arrangements are often times the preferred screw jack system configuration for manufacturers in the food equipment industry.

Application Example - Controlling oven heating element

A leading baked goods manufacturer is developing a new product line that must be pass closer to the top heating element of the conveyor oven. Previously, the top heating element of the oven was fixed and could not move. The new product must be positioned up to 14 inches closer (and be fully adjustable to accommodate the other product versions).

Key Requirements

The top heating element weighs 5,000 pounds.
The manufacturer anticipates only adjusting the height once or twice a month.
The actuators and power source must be located outside of the oven frame.
Travel rate is negligible if the total travel can be reached in less than 60 seconds.

Screw Jack Solution

A 10-ton jack was selected for the mounting condition to fulfill the safety requirements of the application.
This application’s infrequent cycles make an ACME screw jack the best fit.
U arrangement included a single 5-Horsepower 1750 AC Motor that allows full travel in 36 seconds, food-grade grease, compression load and a double safety factor.
Upright rotating jacks allowed the jacks to be easily retrofitted to the existing oven with minimal modifications.
The jacks can be fully loaded in both the retracted and extended positions.

“T” Arrangements

“T” arrangements are another useful screw jack system option for food equipment manufacturers.

Application Example - Positioning large mixer

A manufacturer needs to periodically raise and lower a large cylindrical mixer 8 inches during the mixing cycle to facilitate product testing.

Key Requirements

The 1,700-pound cylinder is mounted on a movable cart, allowing for the final product to be re-positioned to a separate dispensing station.
The jacks will be loaded in tension; therefore column strength will not need to be considered.

Screw Jack Solution

The T arrangement offers a repeatability and reliability that gives the manufacturer assurance their production will not be compromised by ensuring the load is lifted uniformly and safely.
For this configuration, a ball screw jack is used to minimize the size of the motor drive.
Based on the mounting frame, the inverted rotating configurations will be used. Specifications for the arrangement include: a single 1750 AC Motor and 2.5HL-BSJ with a 12–to-one gear ratio and the capability to travel 8 inches in five seconds.

“H” Arrangements

“H” arrangements are one of the most common configurations used for worm gear screw jacks.

Application Example - Controlling a material lift

A food equipment manufacturer of steel frames for the commercial dairy industry is building a material lift which contains a stack of prefabricated frames. The material lift will index up as each frame is removed by an automated grip from the top of the stack.

Key Requirements

The jack will index up 1 inch in 2 seconds every 30 seconds (compression load travels 6 inches).
After the last frame is removed, the jacks will fully retract to the collapsed position in 6 seconds waiting for the next load of frames.
Complete cycle time is 10 minutes running 6 hours per day, 5 days a week.
When fully loaded, the frames hold a total weight of 16,800 pounds, but when the load is fully extended, the weight is less than 5,000 pounds.
The design calls for a four-jack arrangement lifting from underneath the lifting stage, driven by a single motor.
The desired design life for the arrangement is one year, as the application is expected to go through 3,120 cycles a year.

Screw Jack Solution

The frequency of these cycles and suggested design life makes the use of a ball screw jack the best option for this application. Using upright translating jacks allows the jack system to be located under the material lift without creating an obstruction.

Stainless Steel Jack Options

There is an ever-increasing list of opportunities to utilize stainless steel jacks in the food segment. Stainless steel jacks are ideal for use in demanding environments where corrosion resistance is required. All the external components for these jacks are manufactured are manufactured from 300 series Stainless Steel materials and capacities range from 1,300 to 23,000 pounds.

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Nook Screw Jack

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Optimizing Diagnostic Laboratory Throughput

Thu, 04 Jun 2020 12:49:09 -0400

A Rapidly Evolving Diagnostics Landscape

Medical laboratory automation has always been a great fit for the linear motion industry. However, in a post COVID-19 pandemic landscape, linear motion devices such as precision ball screws and modular linear actuators will play an ever-increasing role in improving laboratory throughput, efficiency, and reliability. Ultimately, this provides physicians, clinicians, and patients with accurate test results in the shortest period of time.

The range of applications for linear drives in the medical industry segment is extremely broad. In this blog, we will focus on large-scale automated diagnostic analyzers used in high volume test sample processing.

Laboratories around the world are now experimenting with new tests and methods to provide faster and even more reliable automation for mass-scale screening and virus detection. As a result, linear motion device manufacturers will need to focus on improving laboratory throughput without sacrificing quality and reliability.

Explore Medical Applications

Minimizing human interaction is key to achieving fast and easy handling of time-sensitive samples in these extremely busy laboratory environments. Typically, the human interaction involves reagent and consumables loading, racking/inserting RFID or bar-coded trays, emptying waste and results interpretation. These test results can be automatically sent to remote laboratory information system (LIS) and electronic medical record (EMR) networks for further analysis and diagnosis.

Selecting the proper linear motion device into these highly demanding applications can be challenging when there are many different linear motion technologies to choose from. The value to equipment manufacturers, medical facilities, and patients is dependent on proper selection and implementation of linear motion devices. This is what ultimately drives Overall Equipment Effectiveness (OEE) of the automated diagnostic systems. IE: How well a process is utilized (facilities, time, and material) compared to its full potential.

Typical laboratory demands include:

Reliability
Precision and Repeatable Movement
Size Limitations
Noise Restrictions
Speed and Efficiency

There are two types of linear motion product lines that stand out for these types of automated laboratory equipment situations:

Ball Screw Assemblies
Linear Modular Actuators

Before choosing between the two, it is important to understand the type of application that your equipment design will be supporting. In many cases both technologies are paired within the same equipment for different functions.

Ball Screws

Historically, ball screw assemblies have been the “go-to” linear motion device for medical and laboratory equipment applications. This is because they have provided a myriad of effective solutions for equipment designers. They simply have an outstanding track record for meeting medical research instrumentation requirements.

Ball Screw Assembly with Motor

In this specific area of medical diagnostic analyzers, ball screws are ideal for set-up applications that can include ergonomic adjustable stands for computers and x-ray equipment, along with positioning and inspection cameras, label makers, and printers.

Want to learn more?

Our Engineering Director and resident linear motion expert, Alex Margolin has written extensively on applying precision ball screws in medical applications. You can view his latest white paper by clicking the link below.

Read the White Paper

Modular Linear Actuators

How can modular linear actuators improve the test process?

Automation and Robotics. These linear motion systems in particular, make it possible to execute the massive volume of tests that are required during global health related emergencies such as the SARS outbreak and COVID-19 pandemic. During these fast-paced operations, samples, and consumables must be loaded, unloaded, and transported through the various steps of the diagnostic process. In addition, sensitive fluid handling is required at various stages of the diagnostic testing.

Linear Modular Gantry System

Specialized applications of Modular Linear Actuators:

Driving conveyors or transporting samples
Gantry robotics (Cartesian) for fluid handling, sample extraction, and liquid dispensing
Gantry robots for sample tube handling
Labeling and bar coding sample tubes

Medical Diagnostic Analyzer

Other applications include:

Pick and Place
Blister & Tray Handling
Test Specimen Handling
Filling
Metering/Counting
Insertion and Closures
Carton Packaging
Labeling

Modular Linear Actuators can support robotic systems that work faster and longer. Plus, they minimize errors when managing critical patient samples and provide highly precise positioning that prevents spilling fluids and reagents. Modular Linear Actuators significantly increase test processing capacity, reduce error instances, and improve the ability to track samples. This in turn, increases the overall safety of laboratory personnel due to less risk of contact with contagions.

Hygienic Designs

These laboratory environments also require hygienic designs of the linear motion devices to these highly sensitive samples in accordance with clean room regulations. Their facilities for the industry must meet the highest quality and safety standards. Modular Linear Actuators are ATEX-certified for areas of application such as vacuum technology, clean room technology, and explosion protection. They are highly configurable and can be customized to adapt to any situation. The stainless steel surfaces can be easily and effectively cleaned, and they are highly resistant to various cleaning agents and corrosive chemicals. The modular linear actuators utilize plain and closed profile surfaces and geometric forms to facilitate easy cleaning.

Clean Room Linear Actuator System

Space Saving Technology

When labs invest in automated warehouse logistics, the process usually involves modifications to existing premises. As a result, the testing area is subject to structural restrictions. System manufacturers of linear motion positioning technology systems must therefore be able to adapt. These linear motion systems are easily configured in terms of length and function. This modularity a valuable degree of flexibility for optimizing a lab’s available facility layout.

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Modular Linear Actuators

Replacing Hydraulics with Electric Linear Actuators in Agriculture

Wed, 22 Apr 2020 17:13:09 -0400

A Cleaner and More Efficient Solution for Agriculture and Food Production Equipment

Agriculture and Food Production are two key areas that will receive significantly more focus on a global perspective as we emerge from our current situation. More efficient farming, harvesting, and production are critical to keeping stocked shelves, refrigerators, and freezers in our supermarkets going forward.

As agriculture and food equipment manufactures prepare for this upcoming situation by upgrading and re-designing their machines, it is important to consider some distinct advantages that modern electric linear actuators have over traditional hydraulic systems.

PA Series Programmable Actuator

Companies within the agricultural segment operate ranches, greenhouses, farms, and orchards. They also perform other operations such as reforestation.

Electric Linear actuators provide increased flexibility for a variety of modern-day farming and agricultural applications. This includes both delicate and precise operations as well as rugged heavy duty operations in all weather conditions. Equipment manufactures require solutions that are flexible while being easy to integrate. Increased worker safety is also a growing concern among these equipment manufacturers.

Eco-Friendly, Low Maintenance, Easy Installation

Hydraulics actuators have historically been regarded as "a heavyweight" for their ability to perform high force operations under very heavy pressures. However, unlike hydraulic actuators, electric linear actuators do not utilize hoses, pumps, or toxic fluids. We explore some of the advantages they have over hydraulic systems in further detail below.

Electric Actuator Advantages

No Toxic and Slippery Fluid Spills - They do not require fluids for operation. This makes them very Eco-Friendly as there is no risk of harming the environment. This is especially critical where food harvesting is concerned.
Improved Efficiency - These devices are also Eco-Friendly in another way. They require less power consumption and ultimately save energy. The screw technology is >90% efficient.
Compact Design - Because they do not require hoses or pumps, electric linear actuator systems consume less space (maximizing your equipment footprint).
Easy Installation - Again, there are no hoses, pumps, or messy fluids to deal with. Just bolt on the electric actuator and connect power.
Accurate and Precise Control - These actuators are safer because they can hold load in place if the power fails. They also have programmable speeds for increased accuracy and smoother operation. In addition, programmable stop positions on these actuators significantly reduce wear while dramatically increasing service life. Electric actuators can stop at any position along their length. Feedback sensing options provide sensor feedback on the motion and force applied to the actuator. This allows greater control over the motion and positioning accuracy.
Lower Cost of Ownership - Electric actuators provide trouble free operation without maintenance. This ultimately results in a significant cost savings over time.
Faster Acceleration - More rapid acceleration coupled with smooth, non-stick movement also contribute to better overall performance.

Actuators Utilized in Spreader Application

And as always with the Nook brand, they come standard with outstanding durability, reliability, and long service life.

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Explore Agricultural Applications

Explore Linear Actuators

Linear Actuators for Automated Packaging

Wed, 08 Apr 2020 13:16:25 -0400

Packing a Punch for Packaging Automation.

In my latest blog posts, I've been trying to focus on rapidly evolving industries. The Packaging industry has historically been constantly evolving. However, unlike other upstream production processes, it has typically lagged in automation technology. But that is quickly changing as new technology advances become available that continue to lower the costs of implementing such systems.

The advent of newer sensors, human-machine interfaces (HMIs) and motion controls are increasing the capabilities of packaging automation more than ever. One of the key challenges for automated packaging technology is the ever-increasing need to run multiple different programs for several different products on a single platform (while optimizing cost and floor space). In addition, there is surely no other industry that is so centered around cycle times as the packaging industry.

When it comes to faster cycle times, a fully automated system is the best choice for increasing speed and eliminating errors. We are seeing significantly more interest in customized automated packaging solutions across virtually every industry.

Packaging Line (multiple operations)

Improving Process Control with Electric Linear Actuators

Electric linear actuators are perfect for optimizing the packaging stages of the manufacturing process. Packaging operations pose their own unique challenges. For example, packaging multiple products together on the same machine requires tight synchronization to sort and organize them before placing them into final cartons (with fast throughput and no errors).

Linear actuators are crucial to increasing the efficiency of rapid changeover in an automated packaging process. This is because they can easily be adjusted through software and firmware in order to increase the utilization of a given packaging machine. In addition, they operate with stunning precision of movement and control to virtually eliminate errors.

Precise motion and speed are important, however, there are other key factors to consider as well such as safety and quality. Electric linear actuators are ideally suited to act as a braking mechanism if a fault occurs. This allows the machine to stop as quickly as possible to avoid damaging people or products. With electronics and linear actuators, feedback loops are continuously monitored for proper functionality. Adjustments are automatically made to align the process as needed).

Electric linear motion control is increasingly being used for packaging steps that have traditionally relied on pneumatic and hydraulic technologies. A good example includes automated robotic palletizing equipment that can seamlessly synchronize multiple process steps with electric linear actuators.

Key Advantages of Electric Linear Actuators:

Increased Productivity
Reduced Scrap
Consume Less Space
Low Noise
Increased Flexibility
Controlling multiple setups
Excellent Transfer Speed

Explore Packaging Applications

Modular Linear Actuators for Automated Packaging

Modular Linear Actuators operate very smoothly allowing an automated processes to gently handle parts without damaging them. These linear actuator systems carry out movements precisely and reliably while minimizing shop floor footprint space. Because they are extremely configurable, they easily adapt to various product packaging requirements on a single assembly line. In addition, modular linear actuators also integrate easily into existing facility structures.

These linear motion devices are highly effective in carrying out a multitude of packaging operations including:

Stacking and Un-Stacking
Picking
Clearing
Positioning and Aligning
Sorting

Modular linear actuators adapt to the exact needs of an application while integrating into the existing machine design and footprint - saving space while adding simplicity and increasing flexibility. The modular construction provides the required flexibility without compromising on standardization. This versatility makes it possible to seamlessly combine unique linear axes for a perfect fit - up to the exact length needed. The linear actuators adapt to the machine design (and not vice-versa).

Watch Video Demonstration:

https://www.youtube.com/watch?v=uyOQbQcyvqc

Warehouse Picking System

Modular Linear Actuators

Programmable Linear Actuators for Automated Packaging

Programmable Linear Actuators are ruggedly designed for continuous duty, larger loads, long service life with higher speeds. They incorporate a direct drive or toothed belt drive for high mechanical efficiency that allows for a quiet running performance. Programmable actuators are supplied with either a ball screw or acme screw, and either a servo or stepper drive system.

These devices provide a complete system including motor, drive, controller, and power supply. This makes programmable linear actuators ideal for packaging motion control situations. They are easily programmed to handle multiple different packaging product operations.

In addition, they can be equipped with a wide variety of sensing devices and accessories to control any packaging application.

Programmable Linear Actuators

Want to improve the process control of your automated packaging application?

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Medical Motion: Precision Ball Screw Technologies

Mon, 06 Apr 2020 15:14:28 -0400

Important Factors for Using Ball Screws in Medical/Laboratory Applications

Medical Ball Screws

Controlling linear motion is a common requirement in the development of medical devices and laboratory equipment, and design engineers have numerous linear drive options available to them. However, the nature of medical/laboratory applications presents unique challenges, such as ensuring precise, reliable, and repeatable movement; handling varying dynamic loads within increasingly smaller spaces; operating in clean environments that require minimal amounts of wear debris; and reducing noise, vibration, and mechanical disruptions to instrumentation during operation.

To meet these challenges, designers of medical/laboratory equipment predominantly choose precision ball screws for linear motion control because they exhibit the necessary performance characteristics, are tested for durability, and are available in the variety of size/style options required to support these specialized needs. That’s why ball screws are integral parts of many blood pumping devices in medical settings and automated sample conveyance systems in laboratory environments. In short, ball screws have become the linear motion control solution of choice for medical/laboratory applications.

At its most fundamental level, a ball screw comprises a screw, a nut, and a ball-bearing return mechanism, all packaged within an assembly that when driven by a motor both translates rotary motion into linear motion and controls linear positioning of the attached object, whether it’s a table, platform, pump actuator, sample rack, etc. The screw has a helical groove along the length of its shaft, and the nut includes a matching groove. These grooves act as the inner and outer races along which precision metal balls travel to produce linear motion. Ball screws are more efficient, have a lower coefficient of friction, and support better torque control than other types of linear control screws, making them a better fit for the challenges inherent to medical applications. For example, with torque control in both the driving and driven directions, ball screws allow for better position control in applications with reversing load directions, such as piston-style metering systems.

A typical assembly consists of a screw, nut, and ball bearing return mechanism.

Design Considerations

Yet not all ball screws are the same, and there is a range of important factors that design engineers should consider when using ball screws in designs for medical devices or laboratory instrumentation.

Precise linear motion control

Although ball screws offer higher levels of precision than other linear motion control devices, lead accuracy can vary across different models. The “lead” of the ball screw is the axial distance traveled when advancing the ball screw one revolution. “Lead accuracy” relates to the variation in distance traveled per revolution over the length of the stroke or shaft.

Theoretically, the lead should equal the product of the “pitch,” the axial distance between each screw thread, times the number of screw “starts,” the number of threads on the screw shaft. Lead accuracy is the difference between the actual distance traveled versus the theoretical distance. The International Organization for Standardization (ISO) and Deutsches Institut für Normung (DIN), the German national standards organization, have set lead accuracy standards for precision ball screws for both positional (P) and transport (T) applications. For example, lead accuracy of P5 or T5 is within ±23 microns over a stroke of 300 millimeters; P7 or T7 is ±52 microns over 300 millimeters; P10 or T10 is ±210 microns over 300 millimeters.

Thus, design engineers in the medical/laboratory field need to account for lead accuracy as it applies to achieving the positional and transport accuracy required by their application. When positional/transport accuracy is paramount, select the most precise level of lead accuracy available.

Assessing load conditions

Another critical factor to consider when using precision ball screws for medical/laboratory applications is how well the device can handle the required loading conditions, including the higher dynamic loads that occur within the small spaces required for many types of instrumentation. Design engineers must assess a range of different loading scenarios, particularly when today’s applications require smaller and smaller ball screw assemblies.

Designers need to consider static loads—will the thrust applied to the ball nut damage the assembly—as well as dynamic loads associated with travel of the nut along the screw, linear and rotational speeds, acceleration and cycle rates, and the drive torque involved. They need to make sure that the ball screw that they select will not succumb to tension loads by stretching, or compression loads that squeeze the shaft. Are there side or overturning loads that are part of the mix and need to be evaluated? Is a preloaded ball screw assembly—a ball screw that is preloaded with an internal force between the ball nut and screw assembly to eliminate axial and radial lash—required for a specific application? With many precise medical manufacturing processes, an engineer may need to control assembly stiffness to maximize positioning and stability control in the servo drive control system. Is the ball screw assembly stiff enough for a particular application?

Developing a detailed load profile for the ball screw per its use in a device or mechanism will enable designers to avoid costly missteps and select the appropriate ball screw assembly for their particular application.

Ball screw assemblies have a number of bearing balls that transfer the load between the nut and screw. The thread form in which the bearing balls ride is an ogival shape, also referred to as a gothic arch, formed from two arcs of the same radius with offset centers.

Rolled vs. ground ball screws

Until recently, design engineers had only one option for achieving the exacting precision and higher dynamic load-bearing linear motion demands of many of today’s medical devices and pieces of laboratory equipment: they had to resort to manufacturing custom-ground ball screw assemblies. While this approach satisfies basic performance criteria, it has notable drawbacks.

Grinding custom ball screws is more expensive than purchasing standard manufactured products. Costs can rise even higher if the custom-ground ball screw wears out or needs to be replaced, requiring another round of costly grinding and production. Fortunately, advances in thread-rolling manufacturing technology have made manufactured ball screws with the same levels of precision, lead accuracy, efficiency, and performance as custom-ground ball screws a reality. For example, Nook Industries recently released a line of thread-rolled PMBS^™ Precision Metric Ball Screws with a mechanical, no-slip connection that permanently times the input to the output, providing a more cost-effective, high-precision linear actuation alternative.

Thread-rolled ball screws offer the same degree of fine adjustment, accuracy, and repeatability for controlling positioning as custom-ground ball screws, buy carry several advantages. Because they do not require custom production, delivery is often faster. They also are more affordable—typically, a fraction of the cost of custom-ground ball screws—and are interchangeable, making replacements quick and easy.

Reliability, repeatability, and efficiency

Another reason why most medical device designers prefer precision ball screws for linear motion control is the greater efficiency, dependable repeatability, and operational reliability that they provide. The ball screw design is much more efficient for translating rotary motion into linear movement and positioning control, converting roughly 90 percent of a motor’s torque into thrust. Balls screws achieve this high level of efficiency because the bearing balls transfer and share the load between the nut and the screw. The basic arrangement of this mechanism is ideal for minimizing mechanical wear; ensuring repeatable, predictable performance; eliminating the risk of overheating and jamming; and extending service life and reliability. Due to the high efficiency of the ball nuts, torque control in the driving and driven direction is more consistent than other types of screws, allowing for better position control for medical applications with reversing load directions

That’s not to say that there are not possible problems with ball screws to consider. One potential issue that designers should watch out for is backlash. Backlash relates to the degree of axial and radial motion or play between the screw and nut when the ball screw is not moving. As mentioned previously, preloading the ball screw with an internal force between the ball nut and screw assembly can eliminate axial and radial lash.

Explore Medical Applications

New manufacturing methods for ball screws, such as thread-rolled ball screws, offer the same degree of fine adjustment, accuracy, and repeatability for controlling positioning as custom-ground ball screws, buy have the advantage of being more affordable.

Range of diameters, leads, and options

Of course, using precision ball screws for medical/laboratory linear motion control applications is not a one-size-fits-all proposition. Separate uses will require different-sized diameters and leads, and may demand alternative materials, thread styles, flange types, and/or mounting options. Diameters for precision rolled ball screws range from 6 millimeters to 65 millimeters; leads typically range from one millimeter to 50 millimeters. However, for medical applications, the diameter range is generally 6 millimeters to 16 millimeters and the leads usually are between 2 and 12 millimeters.

Although the screw, nut, and ball bearings are generally available in carbon, alloy, stainless, hardened steels, other materials are often used to support specialized requirements. Threads come in a variety of styles—such as V-thread, cylindrical keyed, and integral-flange—and usually come with either right hand or left hand threads.

When using a flange to mount the ball screw, take note of the available flange types to ensure mounting flexibility. Flanges come in a variety of styles, including DIN-style flanges, with most configurations offering either four, six, or eight mounting holes. Nook also complements ball screws offering end bearing mounting supports, providing complex solution for application.

Profile and ball return mechanisms

When choosing precision rolled ball screws, design engineers in the medical/laboratory field also should consider the type of ball return mechanism, external profile, and wiper system that best fits their particular application. The basic design of a ball screw requires a way to transfer the bearing balls that have reached the end of the groove inside the nut back to the start of the groove at the beginning of the nut. Traditionally, this was accomplished with external tube returns that run along the outside of the nut to return the balls from the end of the nut back to the beginning.

While the external return works just fine, the orientation of the return tube or tubes, which must be installed in a certain way, often creates a wider profile for the ball screw that can get in the way and create clearance issues, especially in the increasingly smaller spaces required for medical devices and laboratory equipment. To overcome this problem, Nook precision ball screws use internal return inserts, which deflect and move the bearing balls within the ball nut body boundaries, providing the most compact solution.

Quiet, Dependable Operation

Because smooth, frictionless, rolling movement characterizes ball screw performance, small motors are generally adequate for driving them. Small motors are much quieter than large motors, and the precision ball screw’s reduced noise and vibration make them the perfect linear control solution for medical and laboratory settings.

Ball screws are also extremely dependable and virtually maintenance-free. Wiper kits or integral wipers are recommended for use with ball nuts to prevent internal contamination by foreign, potentially damaging materials. Lubricants are necessary for maintaining optimal ball screw performance. Without proper lubrication—typically with an oil or lithium-based grease—90 percent of a ball screw’s anticipated service life can be lost. Standard lubrication processes for antifriction bearings apply to ball screws. Depending on the actual ball screw application, corrosion-resistant coatings and/or lubricated finishes may also be warranted.

Always make sure to operate ball screws within the recommended temperature range. Thermal expansion of the screw can cause positioning errors. By keeping the screw operating temperature within the prescribed range, design engineers can avoid this scenario, ensure that lubrication is working properly, and realize dependable, reliable performance.

Precision ball screws remain the “go-to” solution for handling the unique linear motion control requirements of medical/laboratory applications. However, choosing the most suitable ball screw configuration for a particular need demands an objective assessment of application requirements and corresponding ball screw features. By understanding the range of critical factors discussed in this article, design engineers will not only satisfy their linear actuation needs, but will also implement the most efficient, cost-effective, and reliable solution for controlling motion in their medical device or piece of laboratory equipment.

An industrial linear actuator facilitates motion in a straight line, while a conventional motor moves in a circular motion. When considering an electro-mechanical system that utilizes linear actuators versus other technologies, there can be multiple ways to solve one application. All variations differ in accuracy, speed, load, and cost. This will ultimately steer selection of the linear motion solution type.

Alex Margolin

Director of Engineering - Nook Industries

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6 Considerations for Selecting Electric Linear Actuators

Mon, 06 Apr 2020 13:12:07 -0400

These up-front considerations can help you get the most out of your next linear motion project

Consider the big picture

When engineers are designing an electro-mechanical system that utilizes electric linear actuators versus other technologies such as hydraulics or pneumatics, there can be multiple ways to solve one application. All variations differ in accuracy, performance, space (footprint), total cost of ownership, and many other factors. Before deciding on the type of electric linear actuator to be used for a given project, it is very important to consider the big picture of your operations and objectives (and not just focus on product specifications alone). Doing this will ultimately maximize ROI on your equipment investment while speeding up your time to market.

6 Tips to Know Before Buying Your Linear Actuator

Have you and your equipment design team been looking for a reliable linear actuator for your next project? When safety, efficiency, and performance are on the line, you will need to set aside time for research before making a purchase. It is also important to consider the distinct advantages that modern electromechanical actuators have over traditional hydraulic or pneumatic powered actuators. Selecting the right actuator for the job up front can also facilitate a faster time-to-market and you will get the most benefit long-term as your equipment and facility needs evolve.

1. Environment and Safety.

Electromechanical actuators are safer and better for the environment.

Selecting the right device can more effectively prevent accidents in your facility and for your customers. In addition, their designs place less stress on the environment.

Unlike their hydraulic and pneumatic counterparts, electromechanical actuators do not require bulky support systems such as fluids, oils, hoses, and pumps. This eliminates the risk of dangerous leaks that can create slip hazards and environmental contamination (the processes to manage such instances are also very costly).
Electromechanical actuators are self-contained devices that only require minimal periodic lubrication (internal to the sealed device). There are no harmful or dangerous fluids that can leak into the environment.
Electromechanical actuators are >90% efficient, thus they consume less energy, and are thus more environmentally friendly (less strain on resources).

2. Consider the Total Cost of Operation to Maximize ROI.

Other technologies may appear to be initially more cost effective. However, electromechanical actuators clearly provide the best long term investment.

There is increased direct control over the motion profiles of electromechanical actuators. This eliminates the need for extra add-on control components (reducing equipment costs). Changes in adjustment are easily managed with software changes (reducing support costs).
Cleaner operation, less maintenance, and longer operating life ultimately drive down the long term operating costs.
Electromechanical actuators are >90% efficient. This in turn, drives down power consumption and reduces energy costs.

3. Consult with a Linear Motion Support Team Before Making a Purchase.

The linear actuator selection process can be overwhelming... Why struggle unnecessarily?

A potential linear motion partner may already have a solution already waiting to resolve your problem.
Leverage the proven experience and capability of a dedicated and accessible linear motion Design Team.
There are often multiple ways that electric linear actuators can solve a given application problem. Each can have different performance and budgetary impacts. Consulting a linear motion expert early in the development process can quickly direct you to the optimal solution for our individual needs.

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4. Fully Understand the Operating Conditions.

Will the equipment need to operate in any extreme conditions?

It is important to select the proper materials and features that are best suited to the linear actuator's operation environment.

Is it an indoor or outdoor application?
What are the temperature requirements (Heat, Cold, Moisture)
What are the cleanliness requirements (Clean Room, Dirty, etc...)?
Does it need to be explosion-proof?
Are they susceptible to corrosion?

5. Consider the Facility Requirements and Future State of Your Design.

If possible, determine any needed flexibility or expansion of your system going forward. Optimize the long term strategy as much as possible early in development.

What are the current and future floor space/layout limitations?
What additional functionality will be required down the road?
Electromechanical linear actuators consume less floor space because they are self-contained and do not require external supporting equipment such as air lines, hoses, fluids, and compressors or pumps.
Electric linear actuators adapt well to change because they are easily programmed and some versions are highly re-configurable.

Nook's Modular Linear Actuator product line is ideal for optimizing existing and future layout requirements. They can easily be configured and re-configured in order to best meet the evolution of your process and equipment. However, in general all self contained electromechanical actuator product lines are better suited for applications with space limitations.

6. How will the linear actuator interact with the entire system?

Significantly reduce your development cycle by planning out your complete linear motion system in advance. Specifically, how the electronics will interface with the mechanics.

What type of drive is needed? (Servo, Stepper, or AC Motor, etc...)
How precise is the positioning requirement?
What sensing is required (Limit Switches, Encoders, etc...)
How does it need to be mounted?
Does it require safety protections?

Consider using a linear motion provider that supplies complete solutions.

Different types of electric linear actuators include:

Modular Linear Actuator - Great for XYZ positioning duties.

Electric Cylinder - Excellent for heavy duty and outdoor applications.

Programmable Actuator - Perfect when accurate positioning and control is a must.

CC Commercial Actuators - Ideal for low cost, lighter load applications.

Are you considering Electric Linear Actuators as a replacement for Hydraulics or Pneumatic driven linear devices?

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Food Grade Actuator Design Considerations

Thu, 02 Jan 2020 16:19:22 -0500

Hygienic Design Requirements

Standard design guidelines must ensure food processing machinery can be properly cleaned and sanitized after every use. Governing bodies include 3-A Dairy, USDA, etc…

Overview

The IP (Ingress Protection) Rating system was established by the IEC 60529 standard. Recently, it was determined that the prior highest rating of IP68 was still not sufficient for enclosures that were regularly exposed to high pressure or high temperature environments such as those seen in wash down applications. Therefore, a special IP rating of IP69K was created; originating from the German standard DIN 40050-9 which evaluated road vehicles that are exposed to regular and intensive cleaning.

The requirements and testing to meet the IP69K rating in regards to waterproofing actually exceed those seen with the NEMA 4X rating. Subsequently it was found that this rating also served well to meet the cleaning requirements in hygienic applications.

Key Industries for Hygienic Applications:

Food & Beverage Processing
Pharmaceutical
Medical & Diagnostics
Chemical Analysis
Marine and Outdoor

In addition to high pressure and high temperature, certain application will also require the use of cleaning agents to achieve specific hygienic conditions. Nook's new IP69K actuators are specially designed to meet these stringent new requirements.

Key Hygienic Requirements

These criteria are critical for electronic linear actuators to pass the rigorous testing while performing with total reliability and safety in the field.

Should be durable and easy to clean
Must seal tightly to prevent contaminants from mixing with product (grease, etc…)
Exterior components constructed using 316 stainless steel (surface roughness < RA32)
Non-steel components made using FDA approved materials
Resistant to cleaning chemicals
No sharp corners, crevasses, or unsealed metal areas to trap food particles

What's in the numbers?

The charts below provide more detail into what comprises the IP numbering system.

Nook SA-20 Inline Food Grade Actuator

How are Nook actuators ideally suited for the challenge?

In addition to meeting all the safety and cleanliness/cleaning requirements:

You can clean them in place while they are running.

This significantly reduces downtime because it eliminates the need for dis-assembly. Just hose them down while they are running in position.

Clean-In-Place (CIP)

A process allowing complete system cleaning without dismantling it, or the manual involvement of the operator. The insides of Nook actuators do not require cleaning (they are tightly sealed). However, the exterior can be washed down while in operation.

Nook Food Grade Actuators are fully tested to rigorous IP69K requirements. This includes many test cycles at our beta customer evaluation facilities. In addition, Nook actuators have completed the comprehensive test process for IP69K. You can trust Nook Food Grade actuators to perform in the field.

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Programmable Linear Actuators

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