Hydraulic valve control device for I.C. engine

摘要

The hydraulic control device has two spring devices. The second spring (16) can be adjusted during the operation of the control device. When the liquid pressure in the working space (11) is released and the second spring is also released, the first spring (14) holds the lifting valve (1) closed. The energy loss occurring during a motion cycle can be evened out by a cyclic variation of the prestressing of the second spring. The second pressure device may be an oil pressure spring (17), the pressure of which is adjustable in the vicinity of the end positions of the valve motion.