Patent ID: 6131479
Filing Date: 2000-10-17
Classification: F16H,Y10T

Abstract:
A device for converting rotary motion into axial motion comprising:a hollow cylindrically shaped stationary drive housing having a central axis;a rotatable cage for rotation around the central axis;a cylindrical drive shaft disposed within said housing along the central axis and within said rotatable cage;a drive pinion disposed on an end of said drive shaft and having gear teeth;a plurality of planetary rollers mounted in said rotatable cage, said rollers spaced equidistant around said circumference of said drive shaft;a series of drive grooves formed on said planetary rollers, said drive grooves having no contact with said drive shaft;a gear tooth region having teeth located on one end of each of said plurality of planetary rollers said tooth region for meshing with the gear teeth of said drive pinion; anda thrust element slidably disposed outside said drive housing and having at least one internal drive groove for engaging the drive grooves of said rollers, wherein when said drive shaft rotates, it drives said plurality of planetary rollers in a rotary motion causing the grooves on said planetary rollers to engage the drive grooves on said thrust element causing said thrust element to move axially along said central axis; anda first set of bearing grooves arranged around said drive shaft, and corresponding mating bearing grooves disposed on said rollers for axially fixing said planetary rollers around said drive shaft.