| 摘要 |
PURPOSE:To perform detection with less errors at a low and high speed running, by the operation of frequency-division for a slit passing signal generated from a reel, through the use of a switching means, a frequency dividing means, a frequency dividing means, a frequency-division operation and control means and a frequency-division operation means. CONSTITUTION:Slits provided to a hub are counted with a rotary detector 1 of photoelectric or magnetic system to obtain the number of revolutions of a supply side 11 and a winding side 12. Both the number of revolutions are applied to count means 31 and 32 through frequency-dividing 21, 22 and any of the count means 31, 32 is selected at a selective operation means. A switching means 6 transmits a signal to a display means 5 at a low speed mode only. In the high speed mode, an output of a frequency-division operation means 8 is frequency- divided 9 for display through the control of a switching means 10. The means 8 applies 1/4-frequency-division for a larger output signal out of those of the detectors 11 and 12, and a value of smaller output is summed as it is through the control of a frequency-division operation and control means 7. The control means 7 is operated with the amount of tape running indicated by the display 5. Thus, the amount of tape running for each mode can accurately be detected. |
