Process unit and image forming device having an inter-axis distance regulation mechanism

An image forming device comprising:

• a conveyor which conveys a recording paper;
• a photosensitive drum section which includes a photosensitive drum having a rotation center axis and an outer peripheral surface, and a photosensitive drum frame supporting the rotation center axis of the photosensitive drum in a rotatable manner;
• a charger which charges the outer peripheral surface of the photosensitive drum;
• an exposure device which forms a desired electrostatic latent image on the charged outer peripheral surface of the photosensitive drum;
• a developing device section which includes a developing roller having a rotation center axis and an outer peripheral surface, and a developing roller frame that supports the rotation center axis of the developing roller in a rotatable manner, said developing roller applying toner to the electrostatic latent image on the outer peripheral surface of the photosensitive drum to form a toner image from the electrostatic latent image, and said roller frame and said drum frame being coupled so that a mutual distance between the outer peripheral surface of the developing roller and the outer peripheral surface of the photosensitive drum is set in an adjustable manner and so that the rotation center axis of the developing roller is parallel to the rotation center axis of the photosensitive drum and is directed in a same direction with respect to the rotation center axis of the photosensitive drum in a state where the developing roller is located adjacent to the photosensitive drum;
• an inter-axis distance regulation mechanism which is provided on one of the drum frame and the roller frame in a movable manner in multiple stages, and which is in contact with the other of the drum frame and the roller frame, said inter-axis distance regulation mechanism adjusting the mutual distance between the outer peripheral surface of the developing roller and the outer peripheral surface of the photosensitive drum in multiple stages by movement of the regulation mechanism in the multiple stages relative to the one of the drum frame and the roller frame on which the regulation mechanism is provided;
• a transfer device which transfers the toner image formed on the outer peripheral surface of the photosensitive drum to the recording paper conveyed by the conveyor;
• and
• a cleaner which removes toner remaining on the outer peripheral surface of the photosensitive drum after the toner image is transferred from the outer peripheral surface of the photosensitive drum to the recording paper.

A color image forming device comprising:

• a conveyor which conveys a recording paper;
• and
• a plurality of image forming units which are disposed along a conveyance path of the recording paper conveyed by the conveyor, and which form respective desired color images on the recording paper,
• wherein each of the plurality of image forming units comprises:
• a photosensitive drum section which includes a photosensitive drum having a rotation center axis and an outer peripheral surface, and photosensitive drum frame supporting the rotation center axis of the photosensitive drum in a rotatable manner;
• a charger which charges the outer peripheral surface of the photosensitive drum;
• an exposure device which forms a desired electrostatic latent image on the charged outer peripheral surface of the photosensitive drum;
• a developing device section which includes a developing roller having a rotation center axis and an outer peripheral surface, and a developing roller frame that supports the rotation center axis of the developing roller in a rotatable manner, said developing roller applying toner to the electrostatic latent image on the outer peripheral surface of the photosensitive drum to form one of the respective desired color toner images from the electrostatic latent image, and said roller frame and said drum frame being coupled so that a mutual distance between the outer peripheral surface of the developing roller and the outer peripheral surface of the photosensitive drum is set in an adjustable manner and so that the rotation center axis of the developing roller is parallel to the rotation center axis of the photosensitive drum and is directed in a same direction with respect to the rotation center axis of the photosensitive drum in a state where the developing roller is located adjacent to the photosensitive drum;
• an inter-axis distance regulation mechanism which is provided on one of the drum frame and the roller frame in a movable manner in multiple stages, and which is in contact with the other of the drum frame and the roller frame, said inter-axis distance regulation mechanism adjusting the mutual distance between the outer peripheral surface of the developing roller and the outer peripheral surface of the photosensitive drum in multiple stages by movement of the regulation mechanism in the multiple stages relative to the one of the drum frame and the roller frame on which the regulation mechanism is provided;
• a transfer device which transfers the desired color toner image formed on the outer peripheral surface of the photosensitive drum to the recording paper being conveyed by the conveyor;
• and
• a cleaner which removes toner remaining on the outer peripheral surface of the photosensitive drum after the desired color toner image is transferred from the outer peripheral surface of the photosensitive drum to the recording paper.