| 摘要 |
PURPOSE:To realize a secure duplex feeding detection in detecting a sheet thickness variation of an abnormal feeding compared to the zero condition, by furnishing a zero condition adjusting circuit set up at the zero for the normal thickest condition of the related sheet feeding. CONSTITUTION:A gain variable amplifier AMP is furnished to amplify the output of a sheet thickness sensor 22 by the gain settled according to the control signal. A peak hold value is output by giving the output of the amplifier AMP to a peak hold circuit PH through a converting switch SW according to a command signal, and a peak detective circuit is arranged which outputs a signal other than the signals through the peak hold circuit PH, by converting the switch SW when there is no command signal. Moreover, the output is adjusted so that a peak hold value from the peak detective circuit is at zero condition by the command signal, a zero adjusting circuit ZA is furnished to generate around the zero condition after the command signal is put out, the output of the circuit ZA and the set up value are compared, and an output circuit OUT is furnished Remark to stop the feeding system depending on the deflection. |
