ADJUSTABLE VALVE CONTROL SYSTEM WITH TWIN CAMS AND A CAM LIFT SUMMATION LEVER

摘要

A control system is disclosed for operating an engine valve. The system comprises two cams (2, 3) arranged on a common camshaft (1) but rotatable relative to one another. A summation lever (6) has cam followers (4 and 5) in contact with the respective cams (2 and 3). The summation lever (6) is movable in proportion to the instantaneous sum of the lifts of the respective cams. Rockers (8) are provided for opening the engine valve (10) in dependence upon the movement of the summation lever (6). By varying the phase of the cams (2 and 3) relative to one another, it is possible to vary the valve timing, valve lift and/or valve event duration.