| 摘要 |
PURPOSE:To obtain a stable sealing condition, by forming a spiral groove at least on either one side out of the inner circumference of a hole member and the outer circumference of a shaft member, and providing a spiral seal in this spiral groove. CONSTITUTION:A piston 1 is set so as to be slidably reciprocated inside a cylinder 2 in the axial direction, and a spiral seal 4 is inserted in the spiral groove 3 provided on the outer circumference of the piston 1. The sealing between the cylinder 2 and the piston 1 is maintained by this spiral seal 4. Thus, even if an impact force acts on the spiral seal 4, the force is dispersed in the circumferential direction and the vertical direction, and a stable sealing condition can be obtained. |
