Method of coupling sheet metal member and synthetic resin plate member, and structure coupled by this coupling method

A door structure for an image forming apparatus, comprising

• a synthetic resin plate member having a plurality of prepared holes for self tapping screw insertion,
• a pair of left and right stay plates serving as sheet metal members to be coupled to the synthetic resin plate member, said stay plates having a plurality of burring holes formed by subjecting said stay plates to a burring process from the side of coupling surfaces thereof to be connected to said synthetic resin plate member, such that a plurality of burring portions are formed on those surfaces of said stay plates which are opposite to the coupling surfaces, and being positioned on said synthetic resin plate such that the plurality of burring holes correspond to the plurality of prepared holes, respectively,
• a locking fixture provided to one of said pair of stay plates so as to be caught by and removed from a latch fixed to a main body of the image forming apparatus when opening or closing the door structure,
• a handle formed on said one of said pair of stay plates so that said locking fixture is caught by and removed from said latch,
• a support fixture formed on the other one of said pair of stay plates and rotatably engaged with a fixing table, fixed to the main body of the image forming apparatus, through a hinge pin, and
• self tapping screws screwed in the plurality of burring holes and the plurality of prepared holes, respectively, from the side of the surface opposite to the coupling surface.