| 摘要 |
FIELD: mechanical engineering; engines. SUBSTANCE: in offered version, after working stroke of piston and scavenging of cylinder, compression of fresh charge takes place. But, as distinct from two-stroke engine, fuel is not delivered to cylinder and piston does not execute its working stroke. Having passed over TDC, piston moves downwards, and compressed charge expands and, like spring, returns power taken for its compression. Then second scavenging of cylinder is effected, fresh charge is compressed and working stroke of piston takes place. So engine has four strokes: working stroke with subsequent scavenging, compression of fresh charge, return stroke of piston with second scavenging and compression of fresh charge. Quality of gas exchange is enhanced owing to second scavenging. Offered invention makes it possible to create four-stroke engine with high quality of gas exchange on base of two stroke internal combustion engine with contour gas exchange system in which quality of gas exchange is not sufficiently high. EFFECT: simple design and reliable construction without the use of valve timing gear. 2 cl |
