Image forming apparatus having photosensitive drum moving mechanism

摘要

A holder is movable in a horizontal direction between an internal position within the main casing and an external position outside of a main casing. The holder has a first opening extending in the horizontal direction. A drum unit is configured to be held by the holder and is movable in a vertical direction with respect to the holder. The drum unit includes a photosensitive drum having an axis extending in an axial direction, a first end portion and a second end portion opposite to the first end portion in the axial direction. A particular pressure member is positioned in confrontation with the drum unit and urges the first end portion upward through the first opening to permit the photosensitive drum to be in contact with an endless belt when the holder is in the internal position.

主权项

1. An image forming apparatus comprising:
a main casing; a plurality of cartridges arranged in a predetermined direction, each of the plurality of cartridges including a photosensitive drum having an axis extending in an axial direction, each of the plurality of cartridges having a first end portion and a second end portion opposite to the first end portion in the axial direction, the photosensitive drum including a body; a belt disposed above the photosensitive drum of each of the plurality of cartridges that is disposed inside the main casing; a first moving member extending in the predetermined direction perpendicular to the axial direction of the photosensitive drum and disposed below the plurality of cartridges that is disposed inside the main casing, the first moving member being movable relative to the main casing in the predetermined direction perpendicular to the axial direction of the photosensitive drum, the first moving member being movable between a pressing position where the first moving member presses the plurality of cartridges toward the belt and a releasing position where the first moving member releases pressing force to the plurality of cartridges, the first moving member being positioned in confrontation with the first end portion; and a second moving member extending in the predetermined direction perpendicular to the axial direction of the photosensitive drum and disposed below the plurality of cartridges that is disposed inside the main casing, the second moving member being movable relative to the main casing in the predetermined direction perpendicular to the axial direction of the photosensitive drum, the second moving member being movable between a pressing position where the second moving member presses the plurality of cartridges toward the belt and a releasing position where the second moving member releases pressing force to the plurality of cartridges, the second moving member being positioned in confrontation with the second end portion, wherein the first moving member includes a plurality of urging members each
provided for a corresponding one of the plurality of cartridges, configured to urge the first end portion of the corresponding one of the plurality of cartridges toward the belt,positioned below the photosensitive drum of the corresponding one of the plurality of cartridges, andpositioned outside of the body of the photosensitive drum of the corresponding one of the plurality of cartridges in the axial direction.