VARIABLE COMPRESSION RATIO INTERNAL-COMBUSTION ENGINE

摘要

PURPOSE:To eliminate delay of rise of compression ratio thus to improve the response by increasing the operating oil supply under deceleration of an internal-combustion engine where the compression ratio is varied by moving a sub- piston inserted into a sub-cylinder conducted to the combustion chamber hydraulically. CONSTITUTION:A sub-piston 9 is fitted slidably in a sub-cylinder 7 conducted to the combustion chamber 5 in a cylinder head 2 then the operating oil is fed continuously through a check valve 13 into an oil pressure chamber 12 on the rear face and flowed out through a spill port 16 of a stem 11. A diaphragm device 20 connected to a suction manifold will slide a spill ring through a lever 18 to move the sub-piston. A control valve 28 is provided in the operating oil supply path 26 and upon detection of deceleration by means of a deceleration sensing mechanism 31 provided in the negative pressure path 25, a switch 30 is closed during predetermined time to energize a solenoid 27 to increase the opening of the control valve 28 thus to increase the operating oil supply and to advance the sub-piston quickly.