Patent ID: 7198015

Claim:
A variable valve timing system for an internal combustion engine having a crankshaft, the system comprising a cam shaft comprising: (a) a first shaft disposed interior to the cam shaft and operably connected to the crankshaft of the engine such that the first shaft rotates as the crankshaft rotates; (b) a second shalt comprising at least one groove, at least one slot, and a first end having an aperture, wherein the second shaft is disposed interior to the first shaft; (c) a third shaft disposed at least partially through the aperture of the first end of the second shaft comprising a means for moving the second shaft longitudinally, wherein the third shaft moves longitudinally while the second shalt rotates about the third shalt; (d) a first securing means for fixing the second shaft rotationally to the first shaft and allowing the second shaft to move longitudinally with respect to the first shaft, the first securing means disposed through the first shall and into the at least one groove of the second shaft; and (e) a second securing means for fixing the cam shaft rotationally to the first and second shafts, the second securing means disposed through the cam shaft and into the at least one slot of the second shaft, wherein longitudinal movement of the second shaft urges the cam shaft to rotate relative to the first and second shafts and relative to the rotational orientation of the crankshaft.