| 摘要 |
PURPOSE:To increase strength of a piston, by performing an internal chill of an annularly molded member of fine quality or porous graphite with an aluminum alloy made piston so as to suppress the deformation of the piston due to its thermal expansion and contraction. CONSTITUTION:A piston 1 made of aluminum alloy, with which an internal chill of a fine quality or porous graphite annularly molded member 2 is performed, is partly reinforced. In this way, the piston, when its temperature changes, enables a deformation amount by thermal expansion or contraction to be decreased further strength of the piston to be increased. |
