| 摘要 |
There is provided a two-stroke engine configured to effectively prevent blow-by of the scavenging air from the discharge port and to be able to improve the engine output while abating pollution. The two-stroke engine includes a cylinder having an exhaust port and a scavenging port, and a piston, wherein: the piston has a top surface; a piston concave portion is provided in the top surface in the discharge direction; an entire surface of the piston concave portion is formed in an approximately spherical shape; and a slope of the piston concave portion extending from an outer circumferential edge of the piston concave portion in the discharge direction to a deepest portion is steeper than a slope of the piston concave portion extending from an outer circumferential edge of the piston concave portion in the anti-discharge direction to the deepest portion. |
