Patent ID: 7734219

Claim:
A unit comprising: an image carrier; a cleaning device including an elastic plate that abuts the image carrier and extends substantially parallel to a length direction of the image carrier, and a holding plate that holds the elastic plate and having a first positioning hole; and a frame to which the image carrier and the cleaning device are installed, the frame including a side plate arranged orthogonal to the image carrier, the side plate being formed by injection molding melted resin in a mold, the side plate having an orthogonal surface that is orthogonal to the length direction, the side plate being provided with a second positioning hole in the orthogonal surface, a bearing holding a rotation axis of the image carrier and being configured to be fit in the second positioning hole, thereby positioning the image carrier with respect to the frame, a parallel surface extending parallel to the length direction, the side plate being provided with a projecting portion in the parallel surface and the projecting portion is configured to be inserted in the first positioning hole of the holding plate, thereby positioning the cleaning device with respect to the frame; wherein the side plate, having the second positioning hole and the projecting portion, is formed with a single mold that moves along the length direction, and a supporting surface, which is a part of the parallel surface on which the holding plate rests so that the cleaning device does not move in a direction of gravity, is parallel to the length direction.