초록 ▼

An internal combustion engine has electrically controlled hydraulic linkages between engine cams and engine cylinder valves. If it is desired to skip a cam lobe or to modify the response of an engine cylinder valve to a cam lobe, hydraulic fluid is selectively released from the associated hydraulic

An internal combustion engine has electrically controlled hydraulic linkages between engine cams and engine cylinder valves. If it is desired to skip a cam lobe or to modify the response of an engine cylinder valve to a cam lobe, hydraulic fluid is selectively released from the associated hydraulic linkage to permit lost motion between the cam and the engine cylinder valve. Electrically controlled hydraulic fluid valves are used to produce the selective release of hydraulic fluid from the hydraulic linkages. The mode of operation of the engine can be changed (e.g., from positive power mode to compression release engine braking mode or vice versa), or more subtle changes can be made to modify the timing and/or extent of engine cylinder valve openings to optimize engine performance for various engine or vehicle operating conditions (e.g., different engine or vehicle speeds). The valves can be controlled to produce an exhaust gas recirculation event during various operating modes of the engine.

대표청구항 ▼

[ What is claimed is:] [1.]1. A internal combustion engine valve operating system comprising:at least one rocker arm having an internal hydraulic circuit charged with hydraulic fluid;at least one engine valve in operative contact with said rocker arm;means for imparting a compression-release motion

[ What is claimed is:] [1.]1. A internal combustion engine valve operating system comprising:at least one rocker arm having an internal hydraulic circuit charged with hydraulic fluid;at least one engine valve in operative contact with said rocker arm;means for imparting a compression-release motion and an exhaust gas recirculation motion to said rocker arm; andmeans for selectively losing the compression-release motion, said means for selectively losing comprising:a recess provided in an end of the rocker arm, said recess being charged with hydraulic fluid from the internal hydraulic circuit in the rocker arm;a slave piston slideably disposed to extend out of the rocker arm recess under the influence of the hydraulic fluid in the rocker arm recess; anda control valve in hydraulic communication with the internal hydraulic circuit, said control valve being adapted to selectively release hydraulic fluid from the internal hydraulic circuit.