Rotary engine with variable orifice prechamber

In a rotary engine, the combination comprising:

• a housing having walls defining an operating chamber;
• a prechamber associated with said housing;
• an opening in one of said walls establishing fluid communication between said chamber and said prechamber;
• means for introducing fuel into said prechamber;
• a shaft journalled in said housing and extending through said chamber;
• a rotor journalled on said shaft within said chamber and having a surface cyclically brought into proximity with said one wall and said opening for cyclically compressing an oxygen containing medium within said prechamber;
• a control recess in said surface located to pass said opening during engine operation at about or subsequent to maximum compression of said medium and having a configuration such that the flow of combustion gases from said prechamber into said operating chamber is controlled by the shape of said surface about said recess and the proximity of said surface and said recess to said opening at a predetermined, desired rate;
• and
• an additional recess in said surface separate from said control recess, and located to permit free entry of said medium into said opening prior to maximum compression of said medium.