| 摘要 |
PURPOSE:To effectively remove the soot or the like adhering to the wall surface of a cylinder, by fitting a scraper ring in the peripheral portion of a piston between a combustion chamber and a compression ring fitting part. CONSTITUTION:Soot made due to combustion as in a diesel engine is moved by a gas flow in a combustion chamber C. Some soot adheres to the oil-wetted wall surface 1a of a cylinder. When a piston 2 is moved upward in the exhaust process of a four-cycle engine, a flow F is caused near the surface 1a of the cylinder by the movement of the piston and the soot adhering to the cylinder surface 1a is scraped off by a scraper ring 6 and displaced to the central part of the combustion chamber C. After that, the soot is discharged together with exhaust gas. The soot is removed by a soot removing unit provided in an exhaust system. This results in greatly reducing the quantity of soot, which goes into a crankcase, and the deterioration of engine oil. |
