Crankchamber precompression type two-cycle internal combustion engine

摘要

A crankchamber precompression type two-cycle internal combustion engine including cylinder assemblies of an even number consists of at least one pair of cylinder assemblies having working cycles with 180 DEG phase difference, each cylinder assembly having a stepped cylinder constituted by a minor diameter cylinder portion and a major diameter cylinder portion, a stepped piston received in the stepped cylinder and constituted by a minor diameter piston portion and a major diameter piston portion, the minor diameter and major diameter piston portions being in sliding engagement with the minor diameter and the major diameter cylinder portions of the stepped cylinder respectively to provide an annular space serving as sub-intake chamber in the major diameter portions of the cylinders, the sub-intake chambers being connected to an auxiliary scavenging nozzle oriented toward a combustion chamber of the other associated cylinder. The sub-intake chambers are connected to auxiliary carburetors set beforehand in such a manner that they form a mixture of fuel of high quality and air, and crankchambers of the cylinders are connected to main carburetors set beforehand in such a manner that they form a mixture of fuel of low quality and air. By this arrangement, the mixture of fuel of high quality and air is first ignited in the combustion chambers to produce flame surfaces in a large area to enable complete combustion of the mixture of fuel of low quality with air to be achieved.