Patent ID: 8356868

Claim:
An image forming apparatus, comprising: a printhead to print an image on a recording medium placed on a substantially horizontal supporting plane; a carriage on which the printhead is mounted; one or more guide members, each extending along a longitudinal axis substantially parallel to the supporting plane, to support the carriage with the printhead substantially parallel to the supporting plane; and a positioning mechanism provided on a frame of the image forming apparatus to enable positioning of the carriage relative to the supporting plane, the mechanism including: an eccentric bearing connected to each guide member and rotatable around a rotational axis offset from the guide member longitudinal axis to move the guide member relative to the supporting plane; and a rotation restrictor to restrict rotation of the eccentric bearing, the rotation restrictor defining a first point of contact with the eccentric bearing that puts the carriage in a first operational position relatively close to the supporting plane, and a second point of contact with the eccentric bearing that puts the carriage in a second operational position relatively far from the supporting plane, the first and second points of contact being displaceable with respect to the bearing rotational axis to modify the first and second operational positions of the carriage, wherein the rotation restrictor comprises a protrusion to contact the eccentric bearing to restrict rotation of the eccentric bearing, the protrusion being displaceable with respect to the rotational axis of the eccentric bearing to modify the first and second operational positions of the carriage, and wherein the displaceable protrusion moves concentrically around the rotational axis of the eccentric bearing.