Drive screw system with nested mobile supports

A drive screw system comprising

• a drive screw adapted for rotation having proximal and distal ends,
• a drive nut threadedly engaging the drive screw for linearly displacement between the proximal and distal ends of the drive screw in response to rotation of the drive screw,
• means for supporting the drive screw,
• a plurality of bearing assemblies coaxially disposed relative to each other for supporting the drive screw and which automatically moves between the proximal and distal ends of the drive screw in response to the drive nut to dampen the vibrations of the drive screw, and wherein each bearing assembly comprises opposing supports connected to each other including at least one bearing support.

A drive screw system comprising

• a drive screw adapted for rotation having proximal and distal ends,
• a drive nut threadedly engaging the drive screw for linearly displacement between the proximal and distal ends of the drive screw in response to rotation of the drive screw,
• means for supporting the drive screw adjacent to a loading dock,
• at least one bearing assembly for supporting the drive screw and which automatically moves between the proximal and distal ends in response to the drive nut to dampen the vibrations of the drive screw,
• a vehicle restraining device for restraining a vehicle from movement during the loading and unloading thereof, said vehicle restraining device adapted for moving between the proximal and distal ends of the drive screw in response to rotation of the drive screw.

A device for restraining a vehicle from movement during the loading and unloading thereof, the vehicle having at least one wheel supported on the driveway, the device comprising:

• a drive screw adapted for rotation having proximal and distal ends,
• a drive nut threadedly engaging the drive screw for linearly displacement between the proximal and distal ends of the drive screw in response to rotation of the drive screw,
• a lock assembly operatively connected to the drive nut for positioning between a retracted position permitting the vehicle to drive to the loading dock and an extended position in which the lock assembly engages the wheel for restraining movement of the vehicle
• means for supporting the drive screw on a driveway of the loading dock,
• at least one bearing assembly for supporting the drive screw and which automatically moves between the proximal and distal ends in response to the drive nut to dampen the vibrations of the drive screw.

A drive screw system comprising

• a drive screw adapted for rotation having proximal and distal ends,
• a drive nut threadedly engaging the drive screw for linearly displacement between the proximal and distal ends of the drive screw in response to rotation of the drive screw,
• means for rotatably supporting the drive screw in a housing,
• at least one bearing assembly mounted for supporting the drive screw intermediate the proximal and distal ends and which automatically moves between the proximal and distal ends in response to the drive nut,
• an extension tube slidably disposed in the housing and having distal and proximal ends wherein the tube distal end is rigidly affixed to the drive nut so that the extension tube is linearly positioned relative to the housing in response to the movement of the drive nut.