Torch-ignition reciprocating-piston type internal combustion engine

Claim 1

A torch-ignition internal combustion engine of the type having a cylinder with a piston reciprocally slidable therewithin, a cylinder head defining a combustion chamber in conjunction with the cylinder and the piston, a first combustible mixture constituent induction passageway opening into the combustion chamber, a second combustible mixture constituent induction passageway opening into an antechamber formed in the cylinder head having ignition means therewithin, the antechamber opening into the combustion chamber through a constriction, and an exhaust gas passageway leading from the combustion chamber to the atmosphere, comprising: a first recirculation passageway leading from the exhaust gas passageway into the first induction passageway and having a first valve therewithin; and a second recirculation passageway leading from the exhaust gas passageway into the second induction passageway and having a second valve therewithin; said first and second valves being adapted to be responsive to the engine load, whereby said first valve opens only under high load engine operation to recirculate exhaust gas into the combustion chamber, and said second valve opens only under medium and high load engine operation to recirculate exhaust gas into the antechamber.