| 摘要 |
<p>PURPOSE: To securely detect the multiple feeding of sheets by judging abnormality of carrying condition when an interval of images to be detected of the n-th sheet and the n+1-th sheet exceeds the sheet supplying pitch+L (predetermined length) at the time continuously feeding sheets. CONSTITUTION: Marking M is performed to one end of plural transfer papers S1, S2 in the feeding direction at a position displaced by the predetermined length L in the feeding direction per each piece. A multiple feeding detecting sensor 5 detects the passing timing of the marking M for each time of passing of the paper. In the case where normal feeding is performed, the marking M is detected with the timing of P+L (P means the paper feeding pitch). But in the case where the paper sheets are not perfectly separated at the time of passing a nip of a feed roller 2 and a reverse roller 3 and the paper sheets are fed in the multiple feeding, timing of detecting the marking M becomes larger than the timing of P+L. Namely, when the marking M is not detected with the timing of P+L, multiple feeding or non-feeding is judged.</p> |
