Patent ID: 7789050
Filing Date: 2010-09-07
Classification: F02B,F02D

Abstract:
1. A device for varying compression ratio of an internal combustion engine having at least one cylinder including a combustion chamber, a piston translationally movable under action of a connecting rod that is connected by a shaft to the piston and connected to a crankpin of a crankshaft, the piston travelling between top dead center and bottom dead center which provides a dead volume at the top dead center of the piston, a rotary pull eccentric slidably disposed between the crankpin and the connecting rod for varying the compression ratio and means for controlling the movement of the eccentric, wherein the control means includes a hydraulic cylinder comprising a slide in a recess in a support and including fluid chambers in communication with at least one closed circuit, the closed circuit including at least one valve for controlling a flowrate of fluid from one chamber to another chamber, and the at least one valve comprises a piezoelectric device.