Torque pulse compensated camshaft

A torque compensating camshaft for operating a valve for each of a plurality of cylinders of an internal combustion engine, said camshaft comprising:

• an elongate shaftlike portion, said camshaft being rotatable about the longitudinal central axis of said shaftlike portion;
• a plurality of valve operating cams spaced apart from one another along said shaftlike portion, each of said valve operating cams being rotatable with said shaftlike portion and having an outwardly projecting portion which is adapted to be engaged by a cam follower for the valve for one of the cylinders, the cam follower being resiliently biased toward said camshaft, the outwardly projecting portions of the plurality of valve operating cams being circumferentially offset from one another with respect to the axis of rotation of said camshaft;
• and
• compensating cam means, said compensating cam means being rotatable with said camshaft and having a compensating cam surface with a plurality of circumferentially spaced apart, outwardly projecting portions, said compensating cam surface of said compensating cam means being adapted to be followed by a compensating cam follower as said camshaft rotates to introduce torque pulses into said camshaft which are substantially synchronous with and oppositely directed with respect to the torque pulses which are introduced by said plurality valve operating cams as a result of the engagement between each of said plurality of valve operating cams and the cam follower which engages said each of said plurality of valve operating lobes.

In combination:

• a camshaft for operating a valve for each of a plurality of cylinders of an internal combustion engine, said camshaft comprising:
• an elongate shaftlike portion, said camshaft being rotatable about the longitudinal central axis of said shaftlike portion;
• a plurality of valve operating cams spaced apart from one another along said shaftlike portion, said plurality of valve operating cams being equal in number to the number of the plurality of cylinders, each of said valve operating cams being rotatable with said shaftlike portion and having an outwardly projecting portion which is adapted to be engaged by a cam follower for the valve for one of the cylinders, the cam follower being resiliently biased toward said camshaft, the outwardly projecting portions of the plurality valve operating cams being circumferentially offset from one another with respect to the axis of rotation of said camshaft, and
• compensating cam means, said compensating cam means being rotatable with said camshaft and having a compensating cam surface with a plurality of circumferentially spaced apart, outwardly projecting portions, said compensating cam surface of said compensating cam means being adapted to be followed by a compensating cam follower as said camshaft rotates to introduce torque pulses into said camshaft which are substantially synchronous with and oppositely directed with respect to the torque pulses which are introduced by said plurality of valve operating cams as a result of the engagement between each of said plurality of valve operating cams and the cam follower which engages said each of said plurality of valve operating lobes;
• compensating cam follower means comprising contactor means for following said compensating cam surface of said compensating cam means as said shaftlike portion rotates;
• and
• biasing means having a fixed end which is fixedly positioned with respect to an engine block of the internal combustion engine, said biasing means resiliently biasing said compensating cam follower means against said compensating cam surface.