| 摘要 |
PROBLEM TO BE SOLVED: To provide a device capable of image forming, by making the mutually relative image transferring position always synchronized with the multistage type image transferring part. SOLUTION: Gears arranged on the same arranging position of a drum driving system in this device, are composed of respective gear being formed by the same metallic mold. Driving system from a motor is branched to driving gears A1 to A3 for drums 5-1, 5-2 and 5-3 to be used for color, and to the driving gear A4 for the drum 5-4 to be used for black, and then the driving gear A4 only is driven in a monoclomatic mode. At the time of returning to a full color mode, at first all driving gears A1 to A4 are rotated, a sensor 52 detects a projecting piece 52 and recognizes thereby that the driving gears reach a reference position, a clutch is disengaged by a clutch gear, and the driving gears A1 to A4 are stopped. Subsequently, only the driving gear A4 is rotated, the sensor 54 detects the projecting piece 53 and recognizes thereby that the driving gear A4 reaches the reference position, and the motor 38 is stopped. In this way, the gears of driving system are arranged with the reference position of the full color mode, and the transferring relative position of the image of four colors is respectively made matched. |
