| 摘要 |
<p>PURPOSE:To obtain an accurate and sharp image and to reduce the size of the whole device while holding accurate paper intervals during continuous paper feeding by detecting a curl part formed on a transfer material by a detecting means and controlling the peripheral speeds of a couple of rollers by a speed control means with the signal obtained by the detecting means. CONSTITUTION:A sensor 10 as the detecting means is arranged between a photosensitive drum 24 and a fixing roller 11 and, for example, a light source, a phototransistor, an ultrasonic sensor, etc., are used to detect the quantity of deformation of the curl part of the transfer material S. The peripheral speed VR1 of a fixing roller 11 is a little bit slower than the speed VB of a conveyor belt 5 before the transfer material S reaches the fixing roller 11. Then, when the transfer material S reaches the fixing roller 11, a curl part (b) is formed on the transfer material S because of the difference between the speed VB of the conveyor belt 5 and the peripheral speed VR1 of the fixing roller 11, the quantity of deformation of the curl part (b) increases as fixation proceeds, and the curl part (b) is detected by the sensor 10. The peripheral speed of the fixing roller 11 is switched to faster than the speed of the conveyor belt 5 corresponding to the output signal of the sensor 10.</p> |
