Abstract: A fuel intake control system for a supercharged engine including an engine driven supercharger comprises a primary intake passage having a primary throttle valve for controlling the flow of an air-fuel mixture to be supplied to the engine, and an auxiliary intake passage having an auxiliary throttle valve for controlling the flow of at least an air supercharged by the supercharger and adapted to be supplied to the engine. The pressure of the discharged air by the supercharger during a particular engine operating condition is adjusted in dependence on the load imposed on the engine in such a way as to increase with increase of the load. This can be accomplished by controlling the flow of a portion of the discharged air to be relieved to the atmosphere or by controlling the rotational speed of the supercharger.

Abstract: A fuel intake system for a supercharged engine including an engine driven supercharger comprises a primary intake passage having a primary throttle valve for controlling the flow of an air-fuel mixture to be supplied to the engine, an auxiliary intake passage having an auxiliary throttle valve for controlling the flow of at least an air supercharged by the supercharger and adapted to be supplied to the engine, and an electromagnetic clutch for initiating and interrupting the transmission of the drive from the engine to the supercharger. The clutch is in position to establish the drive transmission between the supercharger and the engine only during the high load engine operating condition.

Abstract: An apex seal for rotary piston engines which comprises an elongated sealing piece and an elongated support piece which are superposed throughout their lengths. A side piece is provided at one end of the superposed pieces and has an inclined inward surface which is engaged with a correspondingly inclined end surface of the sealing piece but spaced from a correspondingly inclined end surface of the support piece. A spring is provided for urging the support and side pieces toward the inner wall of the rotor housing.

Abstract: An ignition device for rotary piston engines. The device has an ignition plug disposed in a bore formed in an inner wall surface of a casing of the engine. The plug is of the surface gap and air gap discharge type and has a discharge end constituted by inner and outer electrodes spaced apart from each other through a surface gap discharge distance defined by a surface of an insulative sleeve encircling the inner electrode and an air gap discharge distance defined between the insulative sleeve and the outer electrode. The surface gap discharge distance is not less than 0.6 mm and not greater than 1.3 mm. The air gap discharge distance is not less than 0.7 mm and not greater than 1.4 mm. The surface gap discharge distance is not greater than the air gap discharge distance. The outer electrode has a tip end axially retreated with respect to the surface of the insulative sleeve by a distance between 0.3-1.0 mm.

Abstract: Exhaust gas recycling means by which exhaust gas is recycled and introduced, via a port which is formed in the peripheral wall of a rotary piston engine and which port may also serve for introduction of air or an air-fuel mixture required for low-speed operation of the engine, into a leading zone of an intake chamber. Since the port formed in the peripheral wall is so disposed that the air or air-fuel mixture introduced therethrough tend to be stratified at the leading zone of the intake chamber, the recycled exhaust gas also tends to be stratified at the same leading zone so that the recycled exhaust gas tends to exist in vicinity of the spark plug, whereby less exhaust gas is required to be recycled since a given amount of exhaust gas is more effective in preventing production of nitrogen oxides, and there is correspondingly less engine wear and attendant production of hydrocarbons or similar compounds.

Abstract: Rotary piston engine of fuel injection type wherein fuel injection is performed when the intake air flow is relatively high so that an improved fuel atomization can be attained. Further, the fuel injection timing is also determined from the view point that air-fuel mixture is forced toward the leading part of the intake working chamber. The engine has a peripheral intake port formed in the rotor housing and a side intake port formed in one of the side housings, said side intake port being used only in heavy load range of engine operation. The intake passage leading to the peripheral intake port is inclined in the direction of rotor rotation so that intake fluid is forced toward the leading part of the intake working chamber.

Abstract: Fuel injection type rotary piston engine having side and peripheral intake ports, said side intake port being closed in light load operation and said peripheral port in heavy load operation, said peripheral port having an area which is small in relation to the side port and being closed in each intake stroke after bottom dead center position of the rotor.