Camshaft for an internal combustion engine

In a camshaft for a drive, preferably an internal combustion engine, having a hollow shaft carrying at least one of a cam and a partial cam for rotation therewith, an inner shaft disposed within the hollow shaft and rotatable relative to the hollow shaft, the inner shaft having at least one of a cam and a partial cam disposed outside the hollow shaft attached for rotation with the inner shaft through at least one clearance in the hollow shaft, and a drive gear for driving the camshaft, the improvement comprising means on said drive gear responsive to a parameter characteristic of operating conditions of the drive for adjusting the rotational position of at least one of said inner shaft and said hollow shaft relative to the said drive gear, the adjusting means including a radially extending guide means on said drive gear, an adjustment cam having a cam surface thereon and mounted on the guide means to be radially displaceable with respect to the drive gear therealong, wherein said cam surface extends generally radially to produce, upon radial displacement of said adjustment cam, lateral adjustment of a cam follower means which bears on said cam surface, means arranged between said drive gear and said adjustment cam, responsive to said parameter, for varying the radial displacement of said adjustment cam, cam follower means including a cam follower which bears on said cam surface, thereby to be laterally displaceable by said surface in response to radial movement of said adjustment cam, and biasing means for urging said cam follower against said cam surface, and means for coupling the cam follower means to one of said inner shaft and said hollow shaft for adjusting the relative rotational position of said one shaft.