Mitsubishi Jukogyo Kabushiki Kaisha

Shigeichi Okada

Yoshihide Nakatani

Takafumi Nakahara

Makoto Takata

Takeshi Katoh

Eiji Yaezawa

For the purpose of preventing a decompression passageway in a two-cycle engine from being blocked by carbon soot, facilitating manufacture of a two-cycle engine having decompression structure and eliminating reduction of output power of the two-cycle engine caused by the decompression structure, a known two-cycle engine includes a scavenging passageway formed along an inner wall of a cylinder. The scavenging passageway is directed in the axial direction of the cylinder and communicates with a crank case of the engine. A decompression groove extends in the axial direction of the cylinder on the upstream side of a cylinder cooling airflow at a top end portion of the scavenging passageway. The width and depth of the decompression groove are either varied along the axial direction of the groove so as to be narrowed towards a tip end thereof directed toward a plug, or are provided with a narrowed portion of venturi shape.

Decompression device in a two-cycle engine

A direct-injection spark-ignition engine including a governor for sensing the rotational speed of the engine, fuel injection pumps for injecting fuel at a rate which may be increased or decreased by a fuel control rack connected to the power shaft of the governor, fuel injection nozzles for directly injecting the fuel from the pumps into the respective engine cylinders, ignition plugs for igniting and burning the fuel charges injected from the nozzles by spark discharge, and suction air passages through which air flows toward the combustion chambers, characterized by throttle valves each of which is mounted within each suction air passage to open or close the same, and throttle control mechanisms each of which is connected to the throttle valve and the fuel control rack to open or close the valve in such a way that the valve opening is increased in proportion to an increase in the quantity of fuel injection.

Growing community of inventors

Nagoya, Japan

Shigeichi Okada