HYDRAULIC CONTROL SYSTEM FOR A GAS EXCHANGE VALVE OF AN INTERNAL COMBUSTION ENGINE

摘要

A hydraulic control system for a gas exchange valve 18 of an internal combustion engine comprises a hydraulic actuator 40 associated with the gas exchange valve 18. A hydraulic pump 50 provides a hydraulic energy supply for the hydraulic actuator 40. A first control valve 100 controls hydraulic energy supply to the hydraulic actuator 40. A mechanical energy accumulator 80 is connected between cam means 72 and the hydraulic pump 50. The cam means 72 is capable of periodically storing mechanical energy into the mechanical energy accumulator 80 and of periodically causing its discharge. The mechanical energy accumulator 80 is capable of restoring mechanical energy that is stored therein to the hydraulic pump 50, for producing the hydraulic energy required for controlling the hydraulic actuator 40.