Patent ID: 7769318

Claim:
A tandem photosensitive-member unit comprising: a plurality of photosensitive-member holding units each extending in a first direction and holding a photosensitive member for each of a plurality of colors, the plurality of photosensitive-member holding units being arranged in a second direction perpendicular to the first direction; and a pair of side plates each extending in the second direction, the pair of side plates being disposed at both ends of the arranged plurality of photosensitive-member holding units with respect to the first direction, wherein the tandem photosensitive-member unit is configured to be detachably mounted as an integral unit in a main body of an image-forming device, wherein each photosensitive member has a shaft, wherein the pair of side plates comprises a shaft positioning part that positions the shaft of each photosensitive member held in the photosensitive-member holding unit, wherein the pair of side plates is formed with shaft holes at positions corresponding to each shaft, wherein each shaft is inserted into the respective shaft holes, and wherein the shaft positioning part comprises: contact surfaces provided on peripheral edges of the shaft hole, the peripheral edges being formed along two imaginary intersecting lines; and an urging part that opposes the shaft so that the shaft is interposed between the urging part and the contact surfaces, the urging part urging the shaft toward the contact surfaces.