VARIABLE COMPRESSION RATIO SYSTEM

摘要

A traditional variable compression ratio system for use in a reciprocatmg-piston engine either requires large flows of hydraulic fluid or does not have provision to exchange the hydraulic fluid sufficiently often to prevent overheating of the fluid. A variable compression ratio system (100) for use in a reciprocatmg-piston engine is provided. The system (100) allows the compression ratio in a combustion cylinder (910) of the engine to be varied by varying the distance from a combustion chamber facing surface (113) of a piston (112) to the center of pivotal connection of a connecting rod (114) to a crankshaft (920). The distance is varied responsive to the supply and withdrawal of pressurized hydraulic fluid. The hydraulic fluid is supplied and discharged by a slave pump (140) pivotally connected to the connecting rod (114) at a first end and pivotally connected to a stationary point at a second end. The slave pump (140) supplies and withdraws hydraulic fluid responsive to the rotation of the crankshaft (920) and a hydraulic backpressure controlled using a pressure control valve (170).