| 摘要 |
<p>The present invention comprises: a hydraulic motor (3) rotationally driven as pressure oil from a hydraulic pump (1) is supplied by way of a control valve (5); a remote control valve (6) adapted to switch the control valve; a bypass line (23,24) connected to both hydraulic lines of the hydraulic motor; a communicating valve (10) having a position for closing the bypass line and a position for opening the bypass line; and a throttle valve (14) for controlling the communicating valve, wherein the throttle valve is adapted to set the communicating valve to a closed position at the time when said remote control valve is operated for rotating, and to set the communicating valve to an open position at the time when said remote control valve is returned to a neutral position, as well as to allow the pressure oil of deceleration side to be released by a predetermined time, whereby the oscillation of the machine which may be caused such as at the time when the rotation is stopped in the hydraulic excavator can be avoided. <IMAGE></p> |
