| 摘要 |
PURPOSE:To smoothly and correctly convey a circuit base plate, by changing a distance between two chains in accordance with size of the circuit base plate. CONSTITUTION:Width of a circuit base plate 15 is increased, in a case if desired to increase a distance between two chains 7, 8, a handle 65 is rotated. Then a feed screw shaft 51 is also rotated to move a frame member 25 through an internal thread member 53 in a direction detaching from the chain 7 in a fixed side and increase the distance between the chains 7, 8. Here the tension of chains 46 is relaxed by rotating a mounting bed 44 against force of a tension spring 47 with a pivotal shaft 43 as the center and approximating an idler sprocket 45. In this way, tension of the chain 46 can be automatically adjusted by cooperative action between the sprocket 45 mounted to the bed 44 and the spring 47. |
