| 摘要 |
PURPOSE:To enable a collision object to be rested in a stop position for a given time, by a method wherein an on-off valve is disposed in a communication passage, and through opening of the on-off valve, liquid stored in a liquid accumulating chamber is forced to flow back to a liquid chamber. CONSTITUTION:When the buffer stroke of a piston 7 is completed, the flow of liquid in a cylinder 6 is stopped, and at that moment, a moving valve body 21 is energized through the spring force of a spring 22 for closing. In this case, though the spring force of a spring 8 is exerted on the piston 7, since the spring force is lower than an external force exerted on the piston 7, the piston 7 is left stopped. After, with this state, a given time elapsed, an electromagnetic coil 20 of an electromagnetic on-off valve 18 is energized for excitation, and the moving valve body 21 is attracted for opening. This constitution causes return of liquid, stored in an accumulator 17, to a flow passage 13A through a flow passage 13B to push upward a valve body 15 for opening, and causes the liquid to flow in the cylinder 6 to press the piston 7, and return of a piston rod 2 to its original position. |
