IMAGE FORMING DEVICE

PROBLEM TO BE SOLVED: To obtain a device which makes it possible to assemble a developing device without adjusting the angle of a main pole and to reduce the cost by decreasing the number of the components and the assembly man-hour by providing a developing case with a main pole angle setting part for the angle of a magnetic pole and constituting the device so that the main pole angle setting part is not provided with an opening part. SOLUTION: A developing case 3 is provided with a main pole angle setting part 3a for a magnetic pole angle and this device is constituted so that the main pole angle setting part 3a has no opening part. In case of assembling the developing case 3, a milling cutter surface 2c of a developing roller 2 is inserted and set in the main pole angle setting part 3a provided to a front side plate 3A and a bearing case 5 in which a slide bearing 4 is force-fitted, is inserted and set in the rear opening part 3b of a rear side plate 3B and screwed so that a rear flange 2b is received. Consequently, the developing roller 2 incorporated and fitted in the case 3 sets a specific main pole angle to a photosensitive body based on the precision of the main pole angle setting part 3a and the precision of the milling cutter surface 2c.