| 摘要 |
PURPOSE:To smoothly operate a piston, by forming a lower skirt part to small thickness equivalent or less in an upper skirt part of the captioned piston and resiliently absorbing a deformation amount of a cyliner and the piston. CONSTITUTION:A piston 10 comprises a piston ring part 17, boss part 18 and skirt part 19, here a lower skirt part 19B is formed to a thin thickness equivalent or less in an upper skirt part 19A. In this way, under a condition of side pressure applied in operation, a resilient condition can be optained, in which the piston can not be destructed but easily deformed. |
