| 摘要 |
PURPOSE:To prevent transmission and twisting of high-frequency vibration between a movable portion and a cylinder by providing a sliding contact portion between the movable portion and the cylinder with an elastic body having elasticity along the axial and radial directions of the cylinder. CONSTITUTION:A piston 29 comprises a first elastic body 2 formed of rubber fixed between a first inner ring 20 fitted to a piston rod 3a and an outer ring 21 brought into slidable contact with an inner wall 5c of a cylinder 5. A second elastic body 31 formed of rubber is further fixed between an insertion port 26 of a rod guide 13 and a second inner ring 30 slidably fitted to the piston rod 3a. When high-frequency vibration is applied from the movable portion 4a or the cylinder 5, through the slidable portion between the movable portion 4a and the cylinder 5 is fixed, high-frequency vibration is absorbed by the axial elastic force of the first and second elastic bodies 22, 31, and the twisting between the cylinder 5 and the piston rod 3a is also absorbed by the radial elastic forc thereof. |
