Fuel injection type rotary piston engine

Abstract

Fuel injection type rotary piston engine having side air intake ports formed in the side housings and peripheral air intake port or ports formed in the rotor housing, said side air intake ports being closed during light load or low speed operation of the engine while the peripheral air intake ports are still open, the peripheral ports having an effective passage area which is small in relation to that of the side ports.

I claim: 
     
       1. A rotary piston type internal combustion engine comprising a casing including a rotor housing having a trochoidal inner peripheral wall and a pair of side housings secured to the opposite sides of said rotor housing to define a rotor chamber therein, a substantially polygonal rotor rotatably mounted in said rotor chamber and having apices slidingly contacting the trochoidal inner peripheral wall of the rotor housing so as to define working chambers between the casing and the rotor, means for rotating the rotor so as to effect volumetic changes of each working chamber through intake, compression, combustion and exhaust strokes, first air intake port means formed in at least one of said side housings so as to open into the working chamber which is in the intake stroke, first air intake passage means communicating with said first air intake port means and having first throttle valve means positioned therein, second air intake port means formed in said rotor housing so as to open into the working chamber which is in the intake stroke, second air intake passage means communicating with said second air intake port means and having second throttle valve means positioned therein, means for closing said first throttle valve means in said first air intake passage means during light load operation of the engine while keeping the second throttle valve of said second air intake passage means open, and fuel injection means for injecting fuel into the working chamber which is in the intake stroke. 
     
     
       2. Rotary piston engine in accordance with claim 1 in which said second air intake port means comprises a single intake port. 
     
     
       3. Rotary piston engine in accordance with claim 1 in which said second air intake port means comprises a plurality of small holes. 
     
     
       4. Rotary piston engine in accordance with claim 1 in which said second air intake port means has an effective passage area smaller than that of the first air intake passage means. 
     
     
       5. Rotary piston engine in accordance with claim 4 in which the ratio of the effective passage area of the second air intake port means to that of the first air intake port means is between 1 to 3 and 1 to 9. 
     
     
       6. Rotary piston engine in accordance with claim 1 in which said second air intake passage means is provided with valve means for controlling the passage area thereof.  .Iadd. 7. A rotary piston type internal combustion engine comprising a casing including a rotor housing having a trochoidal inner peripheral wall and a pair of side housings secured to the opposite sides of said rotor housing to define a rotor chamber therein, a substantially polygonal rotor rotatably mounted in said rotor chamber and having apices slidably contacting the trochoidal inner peripheral wall of the rotor housing so as to define working chambers between the casing and the rotor, means for rotating the rotor so as to effect volumetric changes of each working chamber through intake, compression, combustion and exhaust strokes, first fluid intake port means formed in at least one of said side housings so as to open into the working chamber which is in the intake stroke, first fluid intake passage means communicating with said first fluid intake port means and having first throttle valve means positioned therein, second fluid intake port means formed in said rotor housing so as to open into the working chamber which is in the intake stroke, second fluid intake passage means communicating with said second fluid intake port means and having second throttle valve means positioned therein, means for closing said first throttle valve means in said first fluid intake passage means during light load operation of the engine while keeping the second throttle valve of said second fluid intake passage means open and means for introducing fuel into the working chamber during the intake stroke. .Iaddend. .Iadd. 8. Rotary piston engine in accordance with claim 7 in which said second fluid intake port means comprises a single intake port. .Iaddend. .Iadd. 9. Rotary piston engine in accordance with claim 7 in which said second fluid intake port means comprises a plurality of small holes. .Iaddend. .Iadd. 10. Rotary piston engine in accordance with claim 7 in which said second fluid intake port means has an effective passage area smaller than that of the first fluid intake passage means. .Iaddend. .Iadd. 11. Rotary piston engine in accordance with claim 7 in which the ratio of the effective passage area of the second fluid intake port means to that of the first fluid intake port means is between 1 to 3 and 1 to 9. .Iaddend. .Iadd. 12. Rotary piston engine in accordance with claim 7 in which said second fluid intake passage means is provided with valve means for controlling the passage area thereof. .Iaddend.