Patent ID: 6718923
Filing Date: 2004-04-13
Classification: F01L

Abstract:
A hydraulic clearance compensation element for a valve train of an internal combustion engine, comprising opposite clamping regions and pressurisation by lubricating oil, in whicha first and a second component (4, 6), each serving as a clamping element, are held so as to be slidable into each other; the two components (4, 6) between themselves enclose a pressure chamber, tight to the outside, comprising a volume which depends on the mutual position of the two components (4, 6); the pressure chamber (7) can be pressurised by lubricating oil which flows through a supply chamber (8) and is subjected to the lubricating oil pressure; the pressure chamber (7) can be connected to the supply chamber (8) via a spring-loaded one-way valve (10) through which liquid can only flow into said pressure chamber (7); in the connection between the pressure chamber (7) and the supply chamber (8) an additional controllable check valve (11) is provided; between the pressure chamber (7) and the controllable check valve (11) a throttling channel is provided which serves as a bypass to the one-way valve (10); characterised in that the throttling channel is connected to a buffer space (22) whose volume can be changed, wherein the volume, at an internal pressure of the buffer space (22) which is below a specifiable value, assumes a predetermined minimum value, while when a lubricating oil volume flow is acting on the buffer space (22) above this pressure, said volume increases in a volume-proportional manner while building up a potential energy which is acting towards a reversible volume decrease.