| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it to be manufacturable easily and inexpensively as well as to aim at the promotion of yet more lightweightiness. SOLUTION: A piston 10 is composed of an inner member 12 formed into a bottomed cylindrical shape by means of working a steel plate through mainly drawing by a press, and an outer member 14 formed into a bottomed cylindrical shape by means of working a stainless steel plate through mainly drawing by a press, and fitted in and clamped tight to the outside of the inner member 12, respectively. In addition, a ring projection 12c is installed in an opening end edge of a cylindrical part 12a of the inner member 12 by means of upsetting, and then a ring groove 16 for mounting a dust boot or the like is formed in a gap with the opening end edge of a cylindrical part 14a of the outer member 14.</p> |
