| 摘要 |
PURPOSE:To perform the overheat preventing control of a platen glass without providing a temperature sensor on the platen glass and without making a processing speed excessively low by properly delaying the time of starting to decrease the number of copied sheets in accordance with the voltage value of a light emitting lamp for reading an original. CONSTITUTION:This copying machine is constituted so that the number of copied sheets per unit time may be decreased every time the number of consecutively copied sheets exceeds a previously set threshold. Then, an optical image plotted on a photosensitive body K is converted into an electrostatic latent image by a latent image forming part 5 and converted into a toner image by a developing part 6. Furthermore, the toner image is thermally fixed by a fixing part 7 and a paper is ejected to the outside of a machine. While the above processing is performed, a temperature detection part 13 measures the temperature at the proper spot of the fixing part 7, and an off-time after stopping the operation is calculated from the measured temperature by an off- time calculation part 12. Whether electrostatic charging processing is performed to the photosensitive body K is decided by a processing part 14 by setting the off-time as reference. Then, a platen glass temperature calculation part 15 calculates the temperature of the platen glass. |
