Patent ID: 6935285
Filing Date: 2005-08-30
Classification: F02B

Abstract:
1. A two-cycle combustion engine which comprises: a cylinder block having a two-staged cylinder bore defined therein, said two-staged cylinder bore having a reduced diameter bore portion and a large diameter bore portion; a two-staged piston having a reduced diameter piston portion and a large diameter piston portion and drivingly accommodated within the two-staged cylinder bore; an annular auxiliary chamber defined between the large diameter bore portion of the two-staged cylinder bore and the reduced diameter piston portion of the two-staged piston; an air-fuel mixture passage for introducing an air-fuel mixture into a crank chamber; an air passage for introducing air into the auxiliary chamber; a scavenge passage for supplying the air-fuel mixture within the crank chamber into a combustion chamber; an exhaust passage for removing combustion gases from the combustion chamber; and an injection passage formed in the cylinder block for injecting the air within the auxiliary chamber into the combustion chamber and having an injection port that opens into the two-staged cylinder bore at a location adjacent an exhaust inlet port of the exhaust passage and between the exhaust inlet port and a scavenge outlet port of the scavenge passage, the exhaust inlet port being defined on the cylinder bore.