Patent ID: 6024422
Filing Date: 2000-02-15
Classification: B60T,F16H,Y10T

Abstract:
A variable pitch screw-driven system comprising:a body;a rotatable drive screw in the body;a cam sleeve disposed about the rotatable drive screw and including a nut section interacting with the rotatable drive screw through a series of interposed balls, wherein the cam sleeve is linearly translatable in response to rotation of the drive screw;a cam track formed in the cam sleeve to travel in concert therewith, anda cam follower secured to the body and disposed in the cam track, wherein during rotation of the drive screw, linear translation of the nut section effects tracking of the cam follower within the cam track such that rotation of the cam sleeve is effected simultaneously with rotation of the drive screw resulting in an effective variable pitch of the variable screw-driven system so that linear translation of the cam sleeve is effected by both rotation of the drive screw and by rotation of the cam sleeve and nut section.