HYDRAULIC SYSTEM OF ROTATION PROCESSING MACHINE

PROBLEM TO BE SOLVED: To provide a hydraulic system of a rotary working machine, which achieves power saving and low noise.SOLUTION: A hydraulic system 2 of a rotary working machine 1 comprises: first and second bi-directional hydraulic pumps 23L, 23R connected to first and second chamber side ports 21AP, 21BP of a hydraulic cylinder, respectively, to supply and discharge hydraulic oil; first and second servo motors 24L, 24R connected to the first and second bi-directional hydraulic pumps 23L, 23R, respectively, to drive the pumps in forward and reverse directions; a coupling circuit 27 that couples the counter-cylinder side of the first and second bi-directional hydraulic pumps; a hydraulic pressure generator 9 connected to the coupling circuit to give an oil pressure to the first and second bi-directional hydraulic pumps; and a controller 6 that commands the first and second servo motors to control the number of revolutions and a direction of rotation individually to control a position of a piston rod of the hydraulic cylinder. 【課題】回転加工機の油圧装置において省電力ならびに低騒音を実現するものを提供する。【解決手段】回転加工機１の油圧装置２は、油圧シリンダ２１の第１、第２室側ポート２１ＡＰ，２１ＢＰの各々に接続されて作動油を給排する第１、第２双方向油圧ポンプ２３Ｌ，２３Ｒと、第１、第２双方向油圧ポンプの各々に接続されてポンプを正逆方向に駆動する第１、第２サーボモータ２４Ｌ，２４Ｒと、第１、第２双方向油圧ポンプの反シリンダ側を連結する連結回路２７と、連結回路に接続されて第１、第２双方向油圧ポンプへ油圧を与える油圧発生器９と、第１、第２サーボモータを個々に回転数と回転方向とを制御指令して油圧シリンダのピストンロッドの位置を制御する制御装置６とを備える。【選択図】図３