Patent ID: 8099031
Filing Date: 2012-01-17
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a first photoconductive member used during monochrome printing; a second, a third and a fourth photoconductive members used together with the first photoconductive member during full-color printing, and arranged in parallel to the first photoconductive member; a transfer belt, onto an outer peripheral surface of which a toner image formed on the first photoconductive member is transferred during the monochrome printing, and toner images formed on the respective first, second, third and fourth photoconductive members are transferred during the full-color printing; a first, a second, a third and a fourth transfer rollers provided on an inner peripheral side of the transfer belt and respectively arranged in positions opposed to the first, second, third and fourth photoconductive members; a link member that shifts, during the full-color printing, the second, third and fourth transfer rollers to positions where the second, third and fourth transfer rollers are brought into press contact with the respective second, third and fourth photoconductive members via the transfer belt, and shifts, during the monochrome printing, the second, third and fourth transfer rollers to positions where the respective second, third and fourth rollers are separated from an inner peripheral surface of the transfer belt, the link member having a distal end contact surface which has a lower step portion and a higher step portion on a lower surface thereof; a lift roller that is urged in an upward direction to come into contact with the lower step portion or the higher step portion of the distal end contact surface, the second, third and fourth transfer rollers being arranged in order of second, third and fourth transfer rollers and between the lift roller and the first transfer roller; and a fixed roller arranged between the first and second transfer rollers.