Abstract: A motorized anti-backlash linear actuator comprises a motor; a hollow shaft that is rotated about a central axis by the motor, an anti-backlash nut that is nested at least partially inside the hollow shaft; and an externally threaded rod or lead screw that engages with the anti-backlash nut such that the rotation of the hollow shaft and the nut imparts a linear motion to the rod that is substantially free of backlash. Nesting the anti-backlash nut at least partially within the hollow shaft provides greater stability to the actuator, and permits high speed operation.

Abstract: A lead screw device including a lead screw shaft extending along a longitudinal axis having a lead screw thread portion, and a coupling structure at a proximal end of the lead screw shaft. The coupling structure can have a male securement thread and a female securement thread positioned along the longitudinal axis. The female securement thread can extend within the coupling structure at the proximal end of the lead screw shaft. The coupling structure can provide opposed axial threaded securement to a rotatable shaft along the longitudinal axis from opposing axial directions.

Abstract: A lead screw assembly having a lead screw rotatable within a hollow tubular portion of a reinforcing rail. A nut engages with threads of the lead screw and is movable along the reinforcing rail. The lead screw includes plurality of first threaded portions having an outer diameter and extending lengthwise of the lead screw; and at least one second gap portion having an outer diameter that is less than the outer diameter of the first threaded portions. The second gap portion is positioned between adjacent first threaded portions of the lead screw. At least one generally U-shaped bearing is secured within the reinforcing rail and contacts the lead screw at a second gap portion. Each U-shaped bearing supports the lead screw along its length as the screw rotates within the rail, so that the lead screw assembly can be safely operated at high speeds over comparatively long distances while minimizing whipping and vibration of the lead screw.

Abstract: A motorized anti-backlash linear actuator comprises a motor; a hollow shaft that is rotated about a central axis by the motor, an anti-backlash nut that is nested at least partially inside the hollow shaft; and an externally threaded rod or lead screw that engages with the anti-backlash nut such that the rotation of the hollow shaft and the nut imparts a linear motion to the rod that is substantially free of backlash. Nesting the anti-backlash nut at least partially within the hollow shaft provides greater stability to the actuator, and permits high speed operation.

Abstract: An improved Oldham coupling that is a unitary object and in an embodiment comprises a first hub having a first projection and a second hub having a second projection. The two hubs are connected to each other by way of an intermediate disk having a first slot and a second slot, the slots being on opposite sides and perpendicular to each other. The first projection is received into the first slot and the second projection is received into the second slot. Elastomeric material is formed around the circumference of the disk to retain the assembly together as a unitary object.

Abstract: A linear actuator assembly, such as a rod or piston-type linear actuator, comprising a rotating lead screw with external threads; and a nut assembly with threads engageable with the external threads of the lead screw; and a guide tube having a hollow interior portion with at least one internal surface. The lead screw and nut assembly are located within the hollow interior portion of the lead screw, and the guide tube is configured to prevent the nut assembly from rotating with the lead screw. The nut assembly translates in a linear direction within the guide tube as the lead screw rotates. A portion of the nut assembly, such as a wedge, is radially biased against an internal surface of the guide tube. In one aspect, an axial compression spring is pre-loaded against the wedge and pushes the wedge up a ramp surface on the nut, and into the internal surface of the guide tube. The radially-biased wedge helps minimize torsional backlash in the assembly.

Abstract: A lead screw assembly having a lead screw rotatable within a hollow tubular portion of a reinforcing rail. A nut engages with threads of the lead screw and is movable along the reinforcing rail. The lead screw includes plurality of first threaded portions having an outer diameter and extending lengthwise of the lead screw; and at least one second gap portion having an outer diameter that is less than the outer diameter of the first threaded portions. The second gap portion is positioned between adjacent first threaded portions of the lead screw. At least one generally U-shaped bearing is secured within the reinforcing rail and contacts the lead screw at a second gap portion. Each U-shaped bearing supports the lead screw along its length as the screw rotates within the rail, so that the lead screw assembly can be safely operated at high speeds over comparatively long distances while minimizing whipping and vibration of the lead screw.

Abstract: An anti-backlash nut is assembled on a reinforced lead screw for bilateral motion lengthwise of the lead screw as the screw is rotated. A hollow, elongate reinforcing rail extends lengthwise of and surrounds the lead screw. A slot in the rail extends lengthwise of the central axis of the lead screw. The anti-backlash nut comprises two separate portions, each portion having a tongue which extends radially through the slot and has threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated. Spring means are employed for forcing the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash, while the anti-backlash nut translates laterally along the reinforcing rail.

Abstract: An anti-backlash nut assembly is on a reinforced lead screw having a threaded lead screw rotatable about a central axis. A hollow, elongated reinforcing rail extends lengthwise of and surrounding the lead screw. The reinforcing rail has a slot extending lengthwise of the central axis. The anti-backlash nut assembly has a nut moveable along the reinforcing rail. The anti-backlash nut has a pair of separate nut portions. Each nut portion has a tongue extending radially through the slot and having threads engagable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated. A spacing mechanism forces the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash while the anti-backlash nut translates laterally along the reinforcing rail.

Abstract: An anti-backlash nut is assembled on a reinforced lead screw for bilateral motion lengthwise of the lead screw as the screw is rotated. A hollow, elongate reinforcing rail extends lengthwise of and surrounds the lead screw. A slot in the rail extends lengthwise of the central axis of the lead screw. The anti-backlash nut comprises two separate portions, each portion having a tongue which extends radially through the slot and has threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated. Spring means are employed for forcing the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash, while the anti-backlash nut translates laterally along the reinforcing rail.

Abstract: An anti-backlash nut assembly is on a reinforced lead screw having a threaded lead screw rotatable about a central axis. A hollow, elongated reinforcing rail extends lengthwise of and surrounding the lead screw. The reinforcing rail has a slot extending lengthwise of the central axis. The anti-backlash nut assembly has a nut moveable along the reinforcing rail. The anti-backlash nut has a pair of separate nut portions. Each nut portion has a tongue extending radially through the slot and having threads engagable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated. A spacing mechanism forces the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash while the anti-backlash nut translates laterally along the reinforcing rail.

Abstract: An anti-backlash nut is assembled on a reinforced lead screw for bilateral motion lengthwise of the lead screw as the screw is rotated. A hollow, elongate reinforcing rail extends lengthwise of and surrounds the lead screw. A slot in the rail extends lengthwise of the central axis of the lead screw. The anti-backlash nut comprises two separate portions, each portion having a tongue which extends radially through the slot and has threads engageable with the threads of the lead screw for moving both nut portions in reciprocating motion lengthwise of the rail when the screw is rotated. Spring means are employed for forcing the nut portions apart to urge the flanges of their threads into forcible engagement with the threads of the lead screw to prevent backlash, while the anti-backlash nut translates laterally along the reinforcing rail.

Abstract: An anti-backlash nut has flexure members which are continuously biased inwardly against a lead screw by a force-applying sleeve which acts on ramps on the flexure member. The spline means include means on the longitudinal flexure members and the force applying sleeve to impart rigidity to the longitudinal flexure members in a direction tangential to the longitudinal direction of movement of the nut.

Abstract: An anti-backlash nut assembly is disclosed on a reinforced lead screw. The mechanism includes a hollow, elongate reinforcing rail surrounding a lead screw and an anti-backlash nut assembly movable along the reinforcing rail. The anti-backlash nut assembly has at least one portion projecting through a slot in the reinforcing rail and includes threads to engage the threads on the lead screw such that when the lead screw is rotated in either direction, the nut will translate along the rail. The rail may be provided with a sleeve-bearing which, in combination with the rail, serves not only as a guide for movement of the nut but lateral support for the lead screw.

Abstract: An anti-backlash nut, movable along a rotatable screw. The nut has internal threads complementary to the threads in the screw. The nut has two nut halves movable as a unit and also rotatable relative to each other on the screw, and are connected to the nut halves to induce their relative rotation on the screw in opposite directions. There is an elastomeric friction mechanism, such as a washer, between the two halves to limit their relative rotational movement. The elastomeric friction mechanism is enclosed between the nut halves to have uniform compression.

Abstract: A method of treating a metallic machine part to increase wear life and to change surface appearance comprising the steps of roughening the surface, thereafter changing its color by case hardening and, subsequently, increasing the lubricity of the case hardened surface by coating the surface with a pigmented, solid perfluorinated lubricant of a color comparable to the color of the case hardened surface.

Abstract: A rider having a centralizing or radially stabilizing bushing that reduces vibration and a longitudinal stabilizer element or lip to prevent longitudinal translation of the stabilizing bushing. The centralizing bushing maintains contact, alignment, and general stability between the bushing and the shaft and reduces noise and fluctuations between the bushing and the shaft when they are moving relative to each other. The bushing is mounted in the rider and includes a bearing engagable with the shaft and a cap engagable with the longitudinal stabilizing unit. There are high friction, elastomeric means engagable with the bearing for limiting movement of the bearing away from the shaft and the rider is under unbalanced radial load conditions. The coefficient of thermal expansion of the bearing is essentially the same as the coefficient of thermal expansion of the shaft.

Abstract: An anti-backlash mechanism is described in the form of a pair of nuts or nut halves with internal threads complementary to the threads on a lead screw. The mechanism is traslated by rotation of the screw. One of the nuts has an outer cantilevered wall with inner gear teeth which engage outer gear teeth on the other nut. Rotation of one nut with respect to the other nut tightens or loosens an abutting frictional rotation-opposing resistance of an elastomeric washer compressed between the two nuts. The compressed washer exerts a bias force against the nuts opposing axial forces exerted by the lead screw against the flanks of the nut threads.

Abstract: The reinforced lead screw has a hollow, elongated reinforcing rail surrounding a lead screw and a nut-bearing movable along the reinforcing rail. The nut-bearing has a portion projecting through a slot in the reinforcing rail and includes threads to engage the threads on the lead screw such that when the lead screw is rotated in either direction, the nut will translate along the rail. A wedge is slidably mounted on the nut-bearing and is biased towards a central axis. The wedge has a pair of bearing surfaces which engage surfaces of the reinforcing rail to restrict rotation of the nut-bearing. The rail may be provided with a sleeve-bearing which, in combination with the rail, serves not only as a guide for movement of the nut but lateral support for the lead screw.

Abstract: An anti-backlash nut designed to translate along a lead screw in two longitudinal directions is disclosed. The nut has one or more longitudinal flexure members each having one end fixed to the nut and the other one free floating. Internal threads are formed at the free floating ends of the flexure members complementary to the threads of the screw. Incline ramps are located on the exterior of the free floating ends. A flexible compression member in the form of an O-ring surrounds the ramps for continuously urging the threads at the free floating end into forceful engagement with the threads of the screw. There is an adjustable sleeve for urging the O-ring against the ramps with variable force to increase and decrease the force with which the threads of the flexure members engage the threads of the screw.