| 摘要 |
A first piston body (31) is provided with: a first passage (41) which extends axially and which has a first opening (51) open to a first chamber (19) and provided at the surface (31a, 32a) of the first piston body (31), where the first piston body (31) is joined to a second piston body (32); a second passage (42) which has a second opening (56) at the joint surface (31a, 32a), extends axially, and has a third opening (57) open to a second chamber (20). The second piston body (32) is joined to the first piston body (31) so as to interrupt the direct communication of the second opening (56) with the first chamber (19). The second opening (56) has an inner opening section (59) extending further inward radially than the first opening (51). The inner opening section (59) is in communication with a third passage (76) formed in the second piston body (32). |
