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Worm Gear Machine Screw Jacks

Machine Screw Jacks - 1/4 Ton to 100 Ton & 5 kN to 200 kN

The Inch and Metric Worm Gear Machine Screw Jacks incorporate an alloy or stainless steel worm which drives a high strength bronze worm gear (drive sleeve). The worm shaft is supported on anti-friction tapered roller bearings with external seals provided to prevent loss of lubrication. The drive sleeve is supported on anti-friction tapered roller or ball thrust bearings. Rotation of the drive sleeve causes the acme thread lifting screw to translate or rotate, depending upon jack configuration.

The threads are precision formed, typically using Class 2-C (Centralizing) tolerances. Jack lift shaft lead tolerance is approximately ±0.004" per foot. Worm Gear Machine Screw Jacks having gear rations between 20:1 and 32:1 are self-locking and will hold loads without backdriving in the absence of vibrations. All other ratios may require a brake to prevent backdriving.

Depending on size, Upright Translating designs are available with optional accessories such as boots, motor mounts, right-angle reducers, motors, encoders and rotary limit switches.

Available Finishes: Standard Nook Epoxy, Nook Outdoor, Nook Marine (Can also paint to customer specification)

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Alloy - Inch

The jack housing is made of ductile iron and proportioned to support the rated capacity of the unit. The lifting screw is made of alloy steel with a minimum tensile strength of 95,000 psi.

Upright

A lift shaft moves through the gear box and extends out from the top. An integrated nut and worm rotate together. When the lift shaft is held to prevent rotation, it moves linearly through the gear box to move the load.

Inverted

A lift shaft moves a nut as it turns and is fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom.

 

Upright Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the top.

Inverted Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom.

Double Clevis

Moves a load through an arc, such as tracking antennas, hinged doors or air dampers. 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.

Upright Keyed

Prevents rotation of the lift shaft with a square guide attached to the screw translating inside a square stem cover. The square stem tube is supplied with lube fittings. A lift shaft moves through the gear box and extends out from the top. An integrated nut and worm gear rotate together. When the lift shaft is held to prevent rotation, it moves linearly through the gear box to move the load.

Inverted Keyed

Prevents rotation of the lift shaft with a square guide attached to the screw translating inside a square stem cover attached to the jack. The square stem tube is supplied with lube fittings. A lift shaft moves through the gear box and extends out from the bottom. An integrated nut and worm gear rotate together. When the lift shaft is held to prevent rotation, it moves linearly through the gear box to move the load.

Upright Anti-Backlash

Used when reversible load conditions require precision positioning control. Adjustable models reduce backlash to approximately 0.003".

The lash between the drive sleeve thread and the lift screw thread is  controlled by adjusting the top cover. This changes the relative distance between the drive sleeves to compensate for lash. The drive sleeve is split, resulting in reduced life.

Inverted Anti-Backlash

Used when reversible load conditions require precision positioning control. Adjustable models reduce backlash to approximately 0.003".

The lash between the drive sleeve thread and the lift screw thread is controlled by adjusting the top cover. This changes the relative distance between the drive sleeves and compensates for lash. The drive sleeve is split, resulting in reduced life.

 

Stainless Steel - Inch

All external components are manufactured from 300 series Stainless Steel materials. These jacks use a stainless steel worm with a high strength bronze drive sleeve.

Upright

A lifting shaft moves through the gear box and extends out from the top of the worm screw jack. A nut is integrated with the worm gear such that the worm gear and nut rotate together. When the lift shaft is held to prevent rotation, it moves linearly through the gear box to move the load.

Inverted

A lift shaft moves a nut as it turns and is fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom of the jack.

 

Upright Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the top of the jack.

Inverted Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom of the jack.

Alloy - Metric

Upright

A lift shaft moves through the gear box and extends out from the top. An integrated nut and worm rotate together. When the lift shaft is held to prevent rotation, it moves linearly through the gear box to move the load.

Inverted

A lift shaft moves a nut as it turns and is fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom.

 

Upright Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the top.

Inverted Rotating

A lift shaft moves a nut as it turns while being fixed to the worm gear. This causes the load, which is attached to the travel nut, to move along the lift shaft. The lift shaft extends out the bottom.