Patent ID: 6155220
Filing Date: 2000-12-05
Classification: F01L,F16H,Y10T

Abstract:
A cam phaser for controlling the timing of a camshaft driven from a crankshaft of an associated engine, said phaser comprising:a ring gear drivably connected with one of the crankshaft and camshaft, said ring gear having a toothed side;a flexible spline including a toothed side and drivably connected with the other of the crankshaft and camshaft;a piezoelectric wave generator engaging the flexible spline and deflecting it into a nonround configuration having at least one projecting lobe wherein teeth of the toothed side engage teeth of the toothed side of the ring gear, the flexible spline having a differential number of teeth from the ring gear that is a multiple of the number of lobes formed on the flexible spline and engaging the ring gear;said wave generator operating to rotate in a wave the circumferential position of the at least one lobe relative to the flexible spline, causing a change in the phase of the flexible spline relative to the ring gear equal to the spacing of said differential number of teeth for each revolution of the wave formed by the wave generator.