Fuel supply device for a rotary wankel internal combustion engine

Claim 1

A rotary internal combustion engine of the type including an outer body having a cavity therein and an inner body relatively rotatable within the cavity about an axis laterally spaced from but parallel to the axis of the cavity, said outer body having axially spaced end walls and a peripheral wall interconnecting the end walls to define the cavity, the inner surface of the peripheral wall having a multi-lobe profile which is basically an epitrochoid, the inner body having end faces disposed adjacent the end walls for sealing cooperation therewith and a peripheral surface with a plurality of circumferentially spaced apex portions, a seal member carried by each apex portion and engaging the multi-lobe inner surface of the outer body peripheral wall and the end walls in sealing relations to provide a plurality of working chambers between the two bodies which may vary in volume on relative rotation of the two bodies, the induction, compression and ignition, power and exhaust stages of the engine taking place sequentially, a main intake duct communicating with the cavity and into which duct fuel and air is admitted, a throttle valve operably related to the main intake duct, a secondary intake duct of substantially less cross-sectional area than the cross-sectional area of the main intake duct communicating with the cavity downstream of the main intake duct, and an exhaust duct communicating with the cavity upstream of the main intake duct, said secondary intake duct supplying a separate idling combustible mixture into the cavity, means for supplying fuel to the secondary intake duct, and a second duct through which air is fed into the cavity for mixture with the fuel supplied to the secondary intake duct, said second duct receiving air from the air supply to the main intake duct, the arrangement being such that at the start of the induction stage, the chamber is positioned in registry with the main intake duct and then sequentially in registry with the secondary intake duct, with the secondary intake duct being controlled to feed fuel to the chamber during idling of the engine and the main intake duct being controlled to feed fuel to the chamber when the engine is operating at a rate higher than idling and the secondary intake duct only being placed in communication with the exhaust duct upon termination of the exhaust stage.