| 摘要 |
<p>PURPOSE:To perform control with high accuracy and to obtain accurate and sharp images by switching and controlling the peripheral speed of the roller of a fixing means by a speed control means, setting the 1st peripheral speed slower than the speed at which a transfer material is conveyed by a conveying means, and forming a curl part on the transfer material while the transfer material is conveyed by the roller. CONSTITUTION:The front end of the transfer material S which is conveyed by a conveyor belt 5 is detected by a sensor 10 and when the front end of the transfer material S reaches a fixing roller 11, the peripheral speed of the fixing roller 11 is switched and controlled to Vr1 with the detection signal of the sensor. In this case, the rear end of the transfer material S is in image transfer operation at a transfer part 44 and the transfer material S present between the fixing roller 11 and transfer part 44 have a curl part (b). If the curl part (b) becomes too large, an unfixed image contacts some internal part of a main device body and the unfixed image is disordered owing to an increase in the curvature of the transfer material S, so that an accurate image can not be obtained. Then, the fixing roller 11 needs to be driven at a peripheral speed slower than the 1st peripheral speed Vr1 after a time which is long enough to obtain the specific quantity of deformation of the curl part (b) is elapsed.</p> |
