effective especially when applied to the color laser printer 1 in which the drawer unit 70 becomes relatively heavy a second embodiment will be described with reference to fig7 in the second embodiment a recessed portion 103 may be formed on the front cover 100 and a protrusion 3 b may be formed on the housing 3 when the front cover 100 is closed to the housing 3 the recessed portion 103 may be engaged with the protrusion 3 b alternatively the recessed portion 103 may be formed on the housing 3 and the protruding portion 3 b may be formed on the front cover 100 with this structure for example even if a great impact acceleration acts on the laser printer 1 during transportation and a great force inertia force acts on the front cover 100 the force inertia force exerted on the front cover 100 can be received by the hinge mechanism 110 and the protrusion 3 b of the housing 3 thus the hinge mechanism 110 especially pins thereof can be prevented from undergoing a great force thereby minimizing trouble that is likely to occur during transportation of the laser printer 1 such as damage on the hinge mechanism 110 the discussion above addresses a color laser printer however the features herein may be applied to other printers such as a monochrome laser printer the discussion above addresses a direct tandem type laser printer however the present application is not limited.