| 摘要 |
PURPOSE:To eliminate a control system and also facilitate to assemble into a cartridge by constructing a rotation supporting device so that a tension is applied to an image carrying belt mechanically only when a drive part is driven. CONSTITUTION:When a drive roller 2 receives transmission of a rotational force by a drive gear 8, tension gears 9a and 9b are also rotated in the same direction to move racks 10a and 10b and to push lever arms 11a and 11b. As a result, a tension roller 3 is moved rightward about the pivot 7 of the arms to apply tension to an image carrying belt 1. Between the tension gears 9a and 9b and these shafts, a torque limiter is installed and, when a specified tension is applied to the image carrying belt 1, the rotation of the tension gears 9a and 9b is stopped to maintain a constant tension. Also, when the rotation of the drive roller 2 is stopped, the tension gear 9b becomes free, and the rack 10b is pushed back by a spring 12 to release a tension of the image carrying belt 1. |
