A Study of a Compression Ratio Control Mechanism for a Multiple-Link Variable Compression Ratio Engine

An engine compression ratio control system, consisting of a multiple-link mechanism, must be capable of both varying and holding the compression ratio under a condition of torque fluctuations caused by the cylinder pressure and inertial force from moving parts.

A compact system design has been achieved by taking advantage of the features of the multiple-link mechanism, including the use of cylinder pressure assist for easy operation when high speed response is required, and using the holding device which has less energy consumption to maintain the compression ratio.