Patent ID: 7407268

Claim:
A cartridge alignment mechanism, comprising: a carriage comprising a first datum surface perpendicular to a first direction, a second datum surface perpendicular to a second direction substantially perpendicular to the first direction, and a first guide portion movable in the second direction, wherein the first direction and the second direction form a symmetrical plane, and the first guide portion is an extrusion; a holding device comprising an abutting datum surface symmetrical to the symmetrical plane and a second guide portion corresponding to the first guide portion, wherein the second guide portion is a guide slot moving in relation to the first guide portion to move the abutting datum surface in the second direction toward the carriage; and a cartridge detachably installed in the carriage, the cartridge comprising an abutting surface symmetrical to the symmetrical plane and corresponding to the abutting datum surface, a first alignment surface corresponding to the first datum surface, and a second alignment surface corresponding to the second datum surface; wherein, when the cartridge disposed in the carriage, the first datum surface abuts the first alignment surface to align the cartridge in the first direction, the second datum surface abuts the second alignment surface to align the cartridge in the second direction, and the abutting datum surface abuts the abutting surface in the second direction to align the cartridge in a third direction perpendicular to the symmetrical plane.