| 摘要 |
PROBLEM TO BE SOLVED: To provide a closed-loop control system for accurately setting and monitoring a tension working on a photoreceptor belt. SOLUTION: A stepper motor 150 for the belt tension applying device is actuated by a controller 29 so as to pressurize a yoke 170 which is connected to the photoreceptor belt 10 by a steering roll 20. A strain meter 160 is arranged on the yoke 170 so as to detect the pressure of the yoke 170 applied on the photoreceptor belt 10 and to transfer the signal to the controller 29, and, the stepper motor 150 is actuated by the signal, then, the tension applied on the belt 10 is controlled to be a prescribed set quantity. Besides, in the case the friction which is generated between the photoreceptor belt 10 and a driving roll 16 and which is detected by a sensor 180 is reduced during the operation, a pressure applied on the photoreceptor belt 10 is increased by the closed-loop control system, then, a driving function is improved. |
