| 摘要 |
PURPOSE:To supply a shock absorber for vehicles which allows excellent ridability and safe maneuverability by installing to a bottom valve a chamber communicating to a cylindrical chamber through an orifice and by providing a subpiston to be compressed in the chamber and thereby attenuating impact force through two stages. CONSTITUTION:A free piston-shaped subpiston 19 is fitted so as to slide freely in a cylind-shaped space F inside a casing 15. During compression stroke, a piston 4 makes a sliding advance and forces the quantity of oil equivalent to the volume of a rod 5 to flow out from a bottom valve 10 into a reservoir chamber A. The hydraulic pressure in a lower chamber B is increased and allows a valve 13 to open. A specified attenuation force is then obtained. Before that, however, the oil is forced to flow into a chamber G located above the subpiston 19 through an orifice 1. The oil in a chamber H is forced to flow into the chamber A. The volume of the chamber G is increased. The increased volume is equivalent to the volume produced by dropping of the piston. Then a low attenuation force during initial stages is obtained. As the stroke advances, the subpiston 19 moves downwards and forces a passage J to close and open a check valve 13, thereby obtaining a specified attenuation force. |
