| 摘要 |
PURPOSE:To improve sealing performance by forming a piston by a non-magnetic body and the wall of a cylinder by a magnetic body, providing a ring groove on the outer periphery of said piston, and inserting a piston ring in which powder of highly magnetic material is mixed, in said ring groove. CONSTITUTION:A piston 1 is formed by non-magnetic material, the wall 2 of a cylinder is formed by magnetic material, and a ring groove 4 is provided on the piston 1. A piston ring 3, in which highly magnetic microscopic powder of tetrafluoride is mixed and which is magnetized, is inserted in the ring 4. Thereby, the piston ring 3 is attracted by the wall 2 of the cylinder and, accordingly, fluid can be securely sealed. |
