| 摘要 |
PURPOSE:To release the bite of a gear at a detaching time by bringing the projection part of a shutter fluctuated between the protecting position and the retreating position of a photosensitive drum into contact with a cam surface and opening the shutter by resisting to a torsion coil spring. CONSTITUTION:As for a shutter mechanism 24 protecting the exposed part of the photosensitive drum from external light and dust, the torsion coil spring 24f is engaged with the projection part projectingly formed from the supporing part of a shaft presser 24d turnably supporting a shutter arm 24a and angular moment is imparted to the arm 24a. Therefore, when a process cartridge is loaded in an image forming device, the mechanism 24 is automatically opened. Besides, when the cartridge is taken out, a shutter joint 24b is regulated by the turning regulation part of the arm 24a by the pressing force of the spring 24f. Simultaneously, a shutter part 24c is regulated by the turning regulation part 24b2 of the joint 24b. Then, the mechanism 24 is automatically fully opened. |
