Patent ID: 7522858
Filing Date: 2009-04-21
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a main body including: a photosensitive-member unit detachably mounted on the main body, the photosensitive-member unit having a leading end and a trailing end with respect to a mounting direction for mounting the photosensitive-member unit on the main body, the photosensitive-member unit including a plurality of photosensitive members provided for each of a plurality of colors, the plurality of photosensitive members being arranged in a predetermined reference direction, each of the plurality of photosensitive members being rotatable about respective ones of a plurality of rotational axes each extending in an axial direction, wherein the pressing member applies the pressing force to the trailing end in a pressing direction when the photosensitive-member unit is in a mounted state, the pressing direction intersecting the predetermined reference direction, allowing the pressing force to have both a first component in the predetermined reference direction and a second component in a direction perpendicular to the predetermined reference direction, the trailing end being pressed in the predetermined reference direction by the first component; wherein, in the mounted state, the leading end is in contact with the reference member at two contact surfaces including a first contact surface and a second contact surface, the first contact surface defining a first positioning direction that is perpendicular to the first contact surface and that intersects the predetermined reference direction, the second contact surface defining a second positioning direction that is perpendicular to the second contact surface and that intersects both the predetermined reference direction and the first positioning direction, allowing the photosensitive-member unit to be positioned with respect to the main body, wherein both the leading end and the trailing end of the photosensitive-member unit are positioned with respect to the main body at both ends in the axial direction; wherein the reference member comprises an axial member that extends in the axial direction, the axial member being configured to contact the leading end of the photosensitive-member unit at the both ends in the axial direction; wherein the casing includes a pair of main-body side plates disposed, in the mounted state, on both sides of the photosensitive-member unit in the axial direction, each of the pair of main-body side plates being formed with an insertion through-hole through which the axial member extends, the insertion through-hole having a peripheral edge; and wherein the main body further includes an urging member provided at the each of the pair of main-body side plates, the urging member urging the axial member toward the peripheral edge, thereby positioning the axial member with respect to the peripheral edge.