| 摘要 |
PURPOSE:To aim at lowering the work cost by rotatably fitting, a cross form material vertically and horizontally at the front of a truck provided with travelling wheels, providing an arm rotatably at the back column and fixing a rotating wheel at the upper end of the arm provided with a coil spring so as to freely drive the title device in the steel pipe. CONSTITUTION:Two pairs of travelling wheels 7 are provided at a right angle to the front and back and the right and left of a truck 16, and a cross formed target 1 comprising reflecting parts 17 is rotatably fitted on a holder 2 provided at the upper part of a front target column 14, a bearing 5 and a shaft 4 in the constantly vertical and horizontal state by the weight 3 of the lower end. An arm 10 is also rotatably fitted at the supporting point of the fixing board of an arm column 15 at the back of the truck 16, and a rotating wheel 6 is rotatably fitted at the upper end of the arm 10. The wheel 6 is brought in constant contact with the upper inner side of a steel pipe B by means of a coil spring 9 between the column 15 and the arm 10 so as to freely drive the title device in the pipe by the wheel 6 made of rubber etc. as well as by the travelling wheels 7. The work speed is thus improved. |
