Patent ID: 8740349

Claim:
An image forming apparatus, comprising: a carriage which moves and scans in a moving direction perpendicular to a sheet conveying direction, the carriage being provided with a recording head which ejects a liquid droplet through a nozzle of the recording head; a sheet-shaped receiving face member which forms a receiving face which receives a non-contributing liquid droplet which does not contribute to image forming, the non-contributing liquid droplet being ejected from the nozzle to the receiving face member while the receiving face member and a nozzle face of the recording head are separated by a space therebetween, the receiving face member being arranged movably in the moving direction of the carriage; and a drive unit which moves the receiving face member in a receiving face member moving direction in conjunction with movement of the carriage, wherein the drive unit includes a drive axle, a rotating axle member integrally formed and rotatably arranged on the drive axle and having a diameter greater than that of the drive axle, and a coil spring fitted to an outer peripheral face of the rotating axle member, the coil spring has a pressing piece at one end of the coil spring, the pressing piece is configured and disposed to be pressed when the carriage moves to a non-contributing ejection position opposing the receiving face member, when the pressing piece of the coil spring is pressed in a pressing direction, the coil spring is twisted to tighten the coil spring around the outer peripheral face of the rotating axle member, and a further pressing of the pressing piece by the carriage, after the coil spring is tightened around the outer peripheral face of the rotating axle member, rotates the rotating axle member in the pressing direction, and when the carriage evacuates the non-contributing ejection position to move to the print region side, the pressing piece of the coil spring is released and moves in a release direction to provide a gap between the coil spring and the drive axle.