| 摘要 |
PURPOSE:To reduce a pump loss and as well to restrain nitrogen oxide from being created, in a valve lift control device for controlling the lift of a valve, by controlling the rotational position of a valve drive cam. CONSTITUTION:The inclined angle of a lever 15 supporting the rear surface of a rocker arm 14 which is oscillated by a drive cam 12, is controlled by a control cam 16 to change the fulcrum point of the rocker arm 14 in order to control the lift of a valve. Between the drive cam 12 and the timing pulley 20 there is provided a phase control device 22 for controlling the opening and closing timing of the valve. Upon low load operation of an engine intake-air vacuum is lowered to reduce a pump loss while the closing timing of an exhaust valve is put forward upon middle load operation to allow combustion gas to remain in the engine cylinder, thereby it is possible to restrain the creation of nitrogen oxide. |
