POSITIONER FOR SLEWING POSITION OF UPPER SLEWING TYPE WORKING VEHICLE

摘要

PURPOSE:To exactly stop the slewing of an upper slewing type working vehicle by providing a sensor to detect changes in the turning inertial moment of the upper slewing body with changes in attitude and working load of an arm-type working machine and also a controller to control slewing brake forces on the basis of detected values. CONSTITUTION:When a slewing operating part 20 is operated, a slewing command signal R1 is put in a controller 22, a slewing signal R3 is sent out from the controller 22 to switch a valve 26. Pressure oil is then supplied to a motor 11 to cause the upper slewing body to turn. After working load W from a working load sensor 29 is put in an arithmetic unit 19, a slewing acceleration speed V' and detected signals of 1st, 2nd, and 3rd sensors 13, 14, and 15 are successively put in the unit 19, and the turning inertial moment of the slewing body is put in the controller 22. On the other hand, slewing angle theta from a slewing angle meter 16 is put in the controller 22 and compared with slewing command angle signal R2 from a setter 23 for calculation. When a given slewing angle theta1 is input, a brake signal R4 is sent out, and pressure oil is supplied to a slewing brake 12 by the brake controller 28.