| 摘要 |
An image forming apparatus includes a main body (2), an endless belt (24), and a drum unit (12,13). The drum unit is detachably mounted on the main body (2). The drum unit (12,13) is inserted in a mounting direction to mount on the main body (2). The drum unit (12,13) has a first end (54) and a second end (55) that is disposed downstream in the mounting direction. The drum unit (12,13) supports a plurality of photosensitive drums (16) including a black photosensitive drum and color photosensitive drums. The black photosensitive drum has a first axis extending in an axial direction perpendicular to the mounting direction. Each of the color photosensitive drums has a second axis extending in a direction parallel to the axial direction. The black and color photosensitive drums are arranged in the mounting direction. The black photosensitive drum is disposed at a position nearest to the first end (54). The second end (55) is pivotable about the first axis to be movable between an initial position and a pivot position. The black and color photosensitive drums contact the endless belt (24) when the drum unit (12,13) is disposed in the initial position. The black photosensitive drum contacts the endless belt (24) and the color photosensitive drums are separated from the endless belt (24) when the drum unit (12,13) is disposed in the pivot position. |
