Patent ID: 7837401

Claim:
An image forming apparatus comprises: a guide rail comprising a guide surface extending in a predetermined direction; a carriage disposed on the guide surface of the guide rail; a recording head mounted on the carriage; a belt drive mechanism disposed along the guide rail and configured to move the carriage reciprocally along the guide surface, the belt drive mechanism comprising a drive pulley and a driven pulley and a timing belt stretched between the drive pulley and the driven pulley, and wherein the carriage comprises: a carriage body on which the recording head is secured; a belt holding portion configured to hold the timing belt; and an urging member configured to urge elastically the belt holding portion in a direction away from the guide surface, wherein the belt holding portion is disposed in a position offset from a line connecting the drive pulley and the driven pulley in the direction away from the guide surface, and is movable toward the guide surface relative to the carriage body, wherein the urging member comprises a coil spring, and wherein the coil spring comprises a coil portion and an arm portion protruding from the coil portion, the coil portion is in contact with the belt holding portion and the arm portion is in contact with the carriage body.