DEVICE FOR MODIFYING THE OPENING AND CLOSING TIMES OF GAS EXCHANGE VALVES OF INTERNAL COMBUSTION ENGINES

摘要

In a device (1) for modifying the opening and closing times of gas exchange valves of an internal combustion engine, high-frequency knocking of the regulating piston at one of its end positions when the engine is started again is to be avoided by simple means. For this purpose, a slide (18) secured against rotation in relation to a section (19) of the housing connected to a driving wheel (2) is mounted in one of the pressure chambers (15, 16). This slide (18) can be positively coupled to a driven unit (12) by the force of a compression spring, against the falling pressure of the hydraulic medium. This prevents the regulating piston (8) from moving further in the axial direction immediately after the internal combustion engine is started and until the device (1) is filled again with hydraulic medium, thus preventing the high-frequency knocking of the piston at its corresponding end position.