Patent ID: 8768206

Claim:
An image forming apparatus comprising: a main casing; a retaining unit configured to retain a plurality of photosensitive drums juxtaposedly arrayed with each other in a predetermined direction, the retaining unit being movable between an internal position within the main casing and an external position outside of the main casing, each of the plurality of photosensitive drums having an axis extending in an axial direction, each of the plurality of photosensitive drums including a first pressed portion and a second pressed portion opposite to the first pressed portion in the axial direction; an endless belt disposed above the retaining unit that is in the internal position; a plurality of first pressure members each of which urging upward the first pressed portion of each of the plurality of photosensitive drums to permit each photosensitive drum to be in contact with the endless belt when the retaining unit is in the internal position; and a plurality of second pressure members each of which urging upward the second pressed portion of each of the plurality of photosensitive drums to permit each photosensitive drum to be in contact with the endless belt when the retaining unit is in the internal position, wherein the retaining unit includes a pair of side plates, each of the pair of side plates including a plurality of receiving portions each of which is configured to receive each of the plurality of photosensitive drums to be movable in a vertical direction, wherein the first pressed portion and the second pressed portion protrude outward from corresponding ones of the plurality of receiving portions in the axial direction, wherein each of the pair of side plates includes a first plate formed with the plurality of receiving portions and a second plate located outward of the first plate, wherein each second plate includes an outer surface provided with a guide portion, wherein the guide portion is configured to guide movement of the retaining unit between the internal position and the external position.