| 摘要 |
PURPOSE: To provide an image forming device capable of preventing offset caused by temperature rise in the paper non-passing area of a fixing device even when large-size paper is allowed to pass immediately after small-size paper consecutively passes. CONSTITUTION: In the case of consecutively forming an image on the paper 3 of a postcard size, the fifth sheet of paper 3 on which the image is fixed by the fixing device 4, for instance, is ejected to a paper ejection tray 5, and then a sheet of dummy paper 17 whose width is equal to the short width of size A3 is fed to an image forming part A through a guide 16. At such a time, an unfixed toner image is not transferred on the dummy paper 17, and the dummy paper 17 is fed to the fixing device 4 as it is blank. Then, the dummy paper 17 is recovered to a dummy paper tray 12 by a switching pawl 14 through a guide 13 again. Therefore, heat in the vicinity of both ends of a nip part which is not taken away by the paper 3 of the postcard size is taken away by the dummy paper 17, so that the temperature is prevented from excessively rising in the vicinity of both ends, whereby the offset of toner to the paper and the deterioration of parts are easily prevented. |
