| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device quickly calculating a paper size even for 'a sheet of paper fed from a paper supply port separated far from an image forming unit, quickly detecting a paper size error for reducing/ preventing unnecessary discharge of paper, and continuously carrying out image formation without stopping supply of paper even if a paper size error is caused. SOLUTION: This image forming device is provided with an image forming unit 1, paper feeding ports A, B, C, D, E in five levels, a paper feeding passage RS for feeding paper PB and the like fed from the paper feeding ports to the image forming unit 1, and paper detecting sensors 21-25 detecting whether the paper PB exists in the paper feeding passage PS or not. In addition, the image forming device is also provided with a paper length computing means computing an actually measured paper length along the paper passing direction of the fed paper on the basis of a signal indicating existence of paper from the paper detecting sensor 21 and the like. |
