| 摘要 |
PURPOSE:To exactly slew or stop a working machine of slewing type by controlling the electric circuit of the solenoid valve of a control valve provided to a slewing oil-pressure circuit by using a miminum slewing speed obtained from the present slewing angle and speed, set slewing speed, and set stop position of a slewing base. CONSTITUTION:A control valve 9 is provided between a slewing oil-pressure motor 3 and an oil-pressure pump 8 and controlled by solenoid valves 11 and 12 which are controlled by a controller 20 to be controlled on the basis of detected values obtained from the vehicular body angle detector 18 of the slewing base, the stop position thetaf setter 19 of the slewing base, and the operation detector 17 of the control valve 9. By the controller 20, using a minimum value of present slewing speed of calculated from the slewing starting position thetaf, slewing stop position thetaf, set slewing speed thetaM', and present slewing angle theta of the slewing base, the control valve 9 is controlled. The slewing speeds can thus be automatically controlled, and automatic stoppage at set positions can be precisely made with good efficiency. |
