| 摘要 |
PURPOSE:To hasten the falling speed of a weight as well as increase its striking force to a pile by reducing the flow path resistance of a high-pressure working liquid by a method in which the main switch valve and two ports of a cylinder are connected with a short-distance flow path. CONSTITUTION:A high-pressure working liquid is supplied to a main switch valve 54, a flow path 57, a port 36, and the lower chamber 32b of the first cylinder chamber 32, and by the pressure of the liquid, the first piston 45 is raised and a weight 49 is lifted up through a rod 44. The valve 54 is switched to the position-II, the working liquid in the lower chamber 32b is sent into the upper chamber 33a of the second cylinder chamber 33 through the port 36, the flow path 57, the valve 54, the flow path 58, and the port 37, and a striking force is applied through a cap 50 to the pile. Since the valve 54 and the ports 36 and 37 are connected with short-distance flow paths 57 and 58, the flow path resistance is reduced, the falling speed of the weight 59 is accelerated and the striking force is thus increased. |
