| 摘要 |
PURPOSE:To reduce the load on a pump drive motive by coupling two chambers in single rod type cylinder to ports of a two-side discharge type pump with variable discharge amount so as to constitute a closed circuit, and by providing possibility of regenerating the brake energy of cylinder. CONSTITUTION:Head side chamber 13a and a rod side chamber 13b of a single rod type cylinder 13 are coupled with discharge ports 14a, 14b of a two-side discharge type pump with variable discharge amount 14 through lines 19, 24, respectively. These lines 19, 24 are equipped with logic valves 3, 4, and the lines 21, 25 divergent between valves 3, 4 and cylinder 13 are connected to a tank 18. The lines 21, 25 are equipped with logic valves 7, 8. The first named logic valves 3, 4 are opened and closed under control of solenoid valves 1, 2 operated by a control lever 17, while the other logic valves 7, 8 are opened and closed by pilot valves with orifice 5, 6 operated by the pressure of the lines 25, 21 on their respective opposite sides. |
