| 摘要 |
PURPOSE:To obtain a sufficient stroke of the forward-backward movement of a detector in relation to a stack and to make it possible to perform this movement automatically in linkage to an arm, by a constitution wherein a large-diameter drum and a small-diameter durm interlocked with each other are provided rotatably on a boom, and a long flexible member linked to the arm is wound on the small-diameter drum. CONSTITUTION:At the time of stacking operation, an arm 1 is rotated to the right around a shaft 15 up to a position indicated by a solid line by an extending operation of a piston-cylinder device 6. Thereby a rope 5 is loosened as the right end of the arm 1 lowers. Because of this loosening, drums 4 and 17 are rotated in the same number of rotation by the weight on the stack detector 2 side. Consequently, the rope 5 is wound up by the drum 17 while a rope 3 and a signal wire 10 are rolled out from the drum 4. Therefore, a stack 8 is piled up to be in contact with the stack detector 2, and a detection output signal is delivered from the stack detector 2 to a control unit via the signal wire 10. At this time point, namely at the time point of detection, a sufficient margin is still found in the vertical direction between the arm 1 and a bucket wheel 13 and the stack 8. |
