Making Medical Devices Work

Cleveland, OH - October 19, 2011

Nook Industries Perfects Precision In Medical Device Actuation

Advanced medical device designs are evolving rapidly and demand higher standards for medical equipment reliability. Applying linear motion components to these medical applications yield the best results when collaboration begins at the early stages of the design. Modification to current parts or a custom design may offer the optimum solution; therefore, an emphasis must be placed on collaboration during the early stages of design with medical device manufacturers.

Nook Industries (Cleveland, OH) offers a wide variety of standard modular actuators, ball screws and acme screws for medical applications in their extensive catalog. As a leading linear systems and components manufacturer, Nook Industries recognizes that medical application specifications often exceed the capabilities of standard, cataloged products. Nook leverages its decades of expertise when modifying standard parts or creating custom designs for medical applications. Nook utilizes vigorous quality systems, a vertically integrated manufacturing model and implements a disciplined product realization process that reflects the Food and Drug Administration's Quality System Regulation 21 CFR-Part 280.

According to Nook Industries' CEO, Christopher Nook, "We often start with the customer's performance specifications focused on the product's expected life, environmental conditions, material selection and physical size. We then incorporate enhancements to the product's design that address the rigors of most medical applications. This process has allowed us to sell modified standard products to the Medical industry successfully."

The following disciplined realization process as seen in Image 1 in Figure 1 below of a 6 x 1.25mm Stainless Steel Ball Screw is executed for Nook medical device applications.

Priorities For Design:

Beginning with specification requirements provided by the medical device manufacturer, definition of design priorities must be incorporated for finished devices intended for human use including:

  • Performance: load capacity and length/range of travel requirements
  • Efficiency: high-precision/low-precision
  • Efficiency: high-precision/low-precision
  • Envelope: compact
  • Material Constraints: stainless steel, magnetism/non-magnetism, radioactive elements, etc.
  • Operating Environment: non-direct exposure with patients or attached to the human body, etc.

Design Reviews:

Design reviews are conducted at various stages involving comprehensive, systematic, and documented examinations of a design that will evaluate the adequacy of the design requirements and evaluate the capability of the design to meet these requirements.

Designing a ball screw is not practical if it can't be consistently and efficiently produced. Nook leverages SolidWorks© COSMOS software at this stage to provide a full range of integrated modeling and simulation that medical product manufacturers need to design better products, faster - and at lower cost.

Medical Device Trends / Products:

Small Diameter Ball Screws Designed For Compact / Precision Applications:

With the growing worldwide shift toward smaller packaged applications-typically requires lower load capacity and higher precisions. Nook's Precision Screw Group has recently introduced its Small Diameter Ball Screw Assemblies (SD Ball Screw) designed for smaller footprint applications to meet the needs of these medical applications. In addition to medical equipment, these screws are used in robots, guided missiles, unmanned vehicles and aerospace applications.

The small diameter ball screw line was developed as an extension to its Power-Trac™ offering to provide design engineers a globally accepted metric product for compact, portable, and lightweight applications requiring high accuracy, repeatability, and durability.

The small diameter (below 10mm) ball screws are designed with a load capacity of 40-100lbs., and a high precision (lead accuracy measured in microns; 10ths of 1,000s of inches).

  • Lead accuracy of: ± 50μm/300mm - Standard Rolled, ± 25μm/300mm - Precision Rolled
  • Standard diameters from 6mm to 12mm
  • Standard leads from 1mm to 6mm

(See Image 2 in Figure 1 Below)

According to Nook Industries CEO, Christopher Nook, "The Small Diameter (SD) Ball Screw's small size and customizable design offer precise, efficient movement in a compact package for medical device applications."

Designed in metric dimensions to meet universal industry performance standards, Nook catalogs SD Ball Screw sizes from 6mm diameter to 12mm diameter.

Stainless Steel Modular Linear Actuators For Extreme Duty / Hygienic Environments:

(See Image 3 in Figure 1 Below)

To meet the high duty cycles and sterile requirements of pharmaceutical, medical, and clean room applications, Nook also offers an extreme-duty solution with its new Stainless Steel Modular Linear Actuator Series (QLZE / QSZE / QST-KE) Positioning System. Developed by Nook's Precision Actuator Group, these products are designed with a stainless steel cover band that wraps over the square aluminum profiles. The stainless steel cover helps protect the actuator when it is exposed to caustic cleaning solutions.

The stainless steel design requires no bellows to cover the extrusion which typically wears out over time.

The standard single-carriage linear actuators offer push-pull type directional loading that can handle loads up to 1,600 lbs. of force and maximum thrust loads up to 1,100 lbs. of force. Higher load capacities can be achieved with modified carriages configured with additional rollers or bearings added to the specification.

Nook's Stainless Steel Modular Linear Actuator Series meets the corrosive challenges created by harsh chemical environments for food/beverage, packaging and petrochemical industries.

For more information visit Nook's online Modular Linear Actuator Catalog on (page 141).

Corporate Profile:

For over 40 years, Nook Industries, Inc. has been a leading manufacturer of linear motion components and linear motion control systems. Manufacturing one of the most comprehensive selections of integrated linear motion systems in the world, Nook's progressive growth has been achieved through its commitment to quality, continuous improvement, defect prevention, and the use of statistical methods and consistent training to ensure the quality of its products.

Headquartered in Cleveland, Ohio, Nook Industries is an ISO 9001-2008 Registered company that provides controlled motion solutions in a wide range of industries including; transportation, medical/diagnostics, paper, chemical, food/beverage, solar/aerospace, entertainment and communications markets. Clients in these markets rely on the company's products for tooling, product design and engineering flexibility to provide modified standard products to meet their respective application requirements.

Whether the application requires an off-the-shelf linear motion component or an engineered solution tailored to fit your application - Nook provides comprehensive engineering, design and analysis in providing the highest quality linear motion manufacturing solutions on the market today.

For more detailed information, visit the Nook web site at: or call: 1-800-321-7800.

©2011 Nook Industries

Figure 1

Editorial Contact:

Agency Contact: Rachel Kerstetter 216.242.0415