| 摘要 |
PURPOSE:To provide a piston which has less deformation and high heat insulating properties, by a method wherein a hollow pipe, being formed such that a plastic material and thread cloth are alternately laminated and the thread cloth is prevented from being exposed to a surface, is used in the drum body of a piston. CONSTITUTION:A drum body part 10 of a piston is formed by a hollow pipe being formed such that phenole resin 11 and thread cloth 12 are alternately laminated and the thread cloth is prevented from being exposed to a surface, and end plates 20 are engaged with the two ends of the drum part. The piston is low in moisture absorption and is decreased in the occurrence of bending, resulting in prevention of the occurrence of leak due to deformation, and since it has high heat insulating properties, it is excellent in thermal efficiency. |
