Valve control mechanism
OwnerChristopher P. Waltersinventor
Life of this patent
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Abstract
A valve control mechanism is disclosed which permits either or both of (a) axial displacement of the camshaft of an internal combustion engine, and (b) phasing of the camshaft (and hence of the valve operation)—i.e. an advance/retard function. The mechanism preferably includes a piston housed within a cylinder, this arrangement itself being mounted within a front end camshaft pulley. The piston is under hydraulic control, preferably governed by a microprocessor. A mechanical coupling between the piston and the camshaft translates the axial movement of the piston into one or both of axial displacement of the camshaft and relative advancement/retardation of its rotation.
Claims21
In or for use in an internal combustion engine, a valve control mechanism which comprises:
- a camshaft carrying a plurality of cams;
- an input member coupled to the camshaft for rotating the camshaft;
- means for varying the axial position of the camshaft relative to the input member;
- and
- a cam follower for each cam, each cam follower comprising a body which reciprocates in a respective slideway, the body having an abutment face which acts upon the end of a respective single valve stem,
- wherein each cam follower is disposed relative to a respective valve stem such that the abutment face of each cam follower contacts the end of its respective valve stem at a zone of action that is located away from the mid-point, measured in a direction parallel to the axis of the camshaft, of a section through the cam follower in a plane which contains the axis of the camshaft and the axis of the valve stem.
In or for use in an internal combustion engine, a valve control mechanism which comprises:
- (1) a camshaft carrying a plurality of cams;
- (2) an input member coupled to the camshaft for rotating the camshaft;
- (3) means for varying the axial and rotational position of the camshaft relative to the input member,
- (4) a cam follower for each cam, each cam follower comprising a body which reciprocates in a respective slideway, the body having an abutment face which acts upon the end of a respective single valve stem, and having a first dimension in a direction parallel to the camshaft which is smaller than a second dimension in a direction perpendicular to the first direction and perpendicular to the valve stem,
- wherein the cam followers are disposed relatively to the respective valve stems such that contact between the respective abutment face and the valve stem occurs away from the mid point of the said smaller dimension.
Dependencies are inferred from the claim text.