| 摘要 |
PURPOSE:To have a light weight piston by making different parts of the piston from materials characterized by high strength, high heat resistance, light weight and/or high resistance to burning due to out of lubrication, and thereby allowing the piston to sustain a boosted pressure in the cylinder and suppressing likelyhood of occurrence of burning due to out of lubrication during high-speed operation. CONSTITUTION:The oversurface 4 of piston facing the combustion chamber 14 and the piston body 2 consisting of a piston pin boss 6 etc. are made of a high strength material, while the crown part 18 consisting of the top periphery 20 of piston and the upper ring groove 22 is made of a material having high heat resistance and high anti-abrasiveness. Further, the skirt part 30 is made of a light weight material with high resistance to burning due to out of lubrication, and a retaining member 40 to stand with the thrust force is furnished between the skirt part 30 and the piston body 2. Thereby the piston can sustain the boosted pressure in cylinder as well as have an enhanced heat resistance and anti-abrasiveness, to lead well to preclusion of burning due to out of lubrication, and further the construction can be formed light in weight. |
