Adjustable hydraulic valve timing gear

摘要

In an adjustable hydraulic valve timing gear an actuating piston 4, which is displaceable in an actuating cylinder 5, is assigned to each valve 1, spring-loaded in the closing direction. The cylinder 5 is connected by a line 6 to a master cylinder 7, in which a master piston 8 can be displaced by the cam 10 of a camshaft 11. An adjustment of the opening times of the valve 1 is made possible by an axially displaceable rotary slide valve 13, which serves as transmission element between the master cylinder 7 and the actuating cylinder 5 and is driven at the camshaft speed but is adjustable in its phase position relative to the camshaft 11. For terminating of the valve lift the rotary slide valve 13 connects an accumulator 29 to the connecting line 6. In its limit position the axially displaceable rotary slide valve 13 immerses with a shoulder 26 in a damper chamber 24, thereby damping the closing movement of the valve 1.