VALVE CONTROL MEANS

摘要

The present invention provides valve control means for use in an internal combustion engine which has valve means (180), cam means comprising a rotatable camshaft (185) having a first portion (181) and a second portion (182) having a different cross section from the first portion (181). The valve control means comprises first follower means (100) engageable with the valve means (180) and engageable with the first portion (181), hydraulic lash adjuster means (101A, 101B, 102, 103, 104, 106, 107, 108, 109, 110, 111, 112) provided in the first follower means (100), second follower means (150) moveable relative to the first follower means (100) and engageable with the second portion (182) and linking means (160, 163, 167) to enable the first (100) and second (150) follower means to be linked together. The hydraulic lash adjuster means (101A, 101B, 102, 103, 104, 106, 107, 109, 110, 111, 112) has a first member (101A, 101B) which defines a closed bore, a second member (107) movable in the bore of the first member (101A, 101B) and defining with the first member (101A, 101B) a variable volume chamber (108) for hydraulic fluid, conduit means (102, 103, 106) for allowing flow of fluid to the chamber (108) and valve means (109, 110, 111, 112) for controlling the flow of fluid to and from the chamber (108). In use of the valve control means, when the first (100) and second (150) follower means are not linked the motion of the valve means (180) is controlled by the first follower means (100) and the valve means (180) is given in each engine cycle the lift of the first portion (181) and when the first (100) and second (150) follower means are linked the motion of the valve means (180) is controlled by the second follower means (150) and the valve means (180) is given in each engine cycle the lift of the second portion (182).