| 摘要 |
PURPOSE:To detect thickness of band-like substance with high reliability, by using a free roll supported by two fixed rolls. CONSTITUTION:A substance whose thickness is measured 1 is drawn in by a pair of upper and lower drawing-in rolls 2, passes through between one roll 3 out of two rolls 3, 4 fixed by a shaft, and a free roll 5, and is led to the next process by a drawing-out roll 6. The free roll is supported by the two rolls 3, 4, and is not fixed by a rotary shaft. On the shaft core of the free roll, a through-hole 8 is provided in the axial direction, and in the hole, a projector 7a and a photodetector 7b are placed so as to be opposed. If a detected substance exceeding the thickness set in advance passes through between the rolls 3, 5, the shaft core position of the free roll moves, therefore, it is detected by both projector and photodetector. |
