| 摘要 |
PURPOSE:To effectively absorb a shock by an earthquake by providing an orifice groove, serving as the resisting force generating part, so as to extend in a sliding direction of a piston member in the internal wall of a cylinder. CONSTITUTION:A hydraulic shock absorber 7 comprises a shock absorber main unit 8 and a piston member 9 displaced sliding in the shock absorber main unit 8. A cylinder 10 is filled with hydraulic fluid. While the cylinder 10 provides in its internal wall an orifice groove 14, serving as the resisting force generating part, so as to extend in a sliding direction of the piston member 9. When the piston member 9 is displaced not less than a predetermined length, the hydraulic oil in the cylinder 10 passes only the resisting force generating part 14, generating resisting force enabling external force to be absorbed. In this way, a shock by an earthquake can be effectively absorbed. |
