| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the weight of a piston, reduce a manufacturing cost, and improve high speed controllability by integrally forming the piston out of synthetic resin having a thermal deformation temperature higher than a specified temperature. SOLUTION: A cylinder bore 39 is extended through a cylinder block 11 and a single head piston 40 is contained in a cylinder bore 39. Rotational movement of swash plate 23 is converted into longitudinal reciprocation movement of the single head piston 40 through a shoe 41. The single head piston 40 is longitudinally moved in the cylinder body 39. In which case, the single head piston 40 is formed as a solid body through injection-molding by using synthetic resin, such as a polyimide raw material, having a thermal deformation temperature of 150 deg.C or more. The peripheral temperature of the single head piston 40 is 150 deg.C or less. Even when the increase of the temperature of the single head piston 40 due to disturbance of the single head piston 40 and the cylinder bore 39 is taken into consideration, there is hardly any fear of thermal deformation occurring the single head piston 40.</p> |
