Pump System and Decoupler for Supplying Pressurized Hydraulic Fluid to a Hydraulically Actuated Valvetrain

摘要

A pump system for supplying pressurized hydraulic fluid to a hydraulic valve actuation system for operating engine valves of an internal combustion engine comprises a substantially conventional main pump, driven by the engine, which supplies the necessary volume of pressurized hydraulic fluid when the engine is running. The system comprises a booster pump that supplies in conjunction with the main pump the necessary volume of hydraulic fluid during starting/cranking of the engine. The main pump is preferably designed and constructed for operating efficiency during engine operating conditions while the booster pump is preferably designed and constructed for operating efficiency during cranking/starting of the engine.