| 摘要 |
<p>PURPOSE:To detect lateral slip of a sheet, the distance thereof, and oblique movement of the sheet in a duplicating device, by providing a detecting member having a detecting surface with a given area. CONSTITUTION:When a sheet passes through the detecting surface of a light collecting element 16, the light collecting element 16 outputs a detecting signal according to the area, covered by the sheet, of the detecting surface. During such passage, a plurality of comparators 19-22 compare the signal values of detecting signals with respective different reference values, and if the signal value exceeds the reference value, a comparing signal is succesively outputted, a microcomputer 31 receives the comparing signal, said comparing signal number is compared with a set signal number, and from a difference therebetween the lateral slip direction and the slip distance of the sheet are detected. Further, oblique movement of the sheet is detected through comparison of the shortest input time of the comparing signal with a set first time, and the direction of inclination of the sheet is detected by comparing a time, for which a variation rate from a differential circuit 28 continues to be a positive or a negative value, with a set second time.</p> |
