Variable compression ratio engine

Abstract

Abstract PURPOSE:To raise the temperature of exhaust gas to maintain the purifying function of an engine exhaust gas purifier satisfactory by providing a catalytic sensor in the engine exhaust gas purifier so that a device for changing the volume of a combustion chamber is actuated in the direction of decreasing a compression ratio when the exhaust gas is lower than a predetermined temperature. CONSTITUTION:A catalytic type exhaust gas purifier 7 is disposed in an engine exhaust passage 6, and a cylinder 2 is provided with the second cylinder 9 communicated with a combustion chamber 9 and a compression ratio changing piston 10. A control circuit 24 which receives signals from a load sensor 25, a rotational speed sensor 26, a knock sensor 27, etc., computes a compression ratio giving an optimum combustion efficiency, and controls the position of the piston 22 through an actuator 22. The control circuit 24 receives a signal from a catalytic temperature sensor 8 and compensates a signal S6 in the direction of decrease in the compression ratio to lower combustion efficiency when a temperature is lower than a predetermined temperature, so that the temperature of exhaust gas is raised to sufficiently ensure the function of the exhaust gas purifier.

Inventors

• 👤 Mitsuo Hitomi
• 👤 光夫 人見
• 👤 Akio Nagao
• 👤 長尾　彰士

Bibliographic Details