To provide a shutter case structure which is improved in appearance of a connection portion between each of a top plate and a front plate, and a side plate when viewed from the side, without protrusion or exposure of a head of a fixture to the outside.

There is provided a shutter case 10 which has the top plate 12, the front plate 14, and the right and left bracket side plates 16, and is formed like a rectangular box. Each bracket side plate 16 has its end erected to form a connection margin 20 which is then stepped to form an engaging portion 24 connected to an inner surface of connection edges of right or left ends of the top plate 12 and the front plate 14. Thus the connection edges of the top plate 12 and the front plate 14 are connected to be flush with the connection margin 20 at the end of the bracket side plate. Further the bracket side plate 16 has a recess 30 formed therein at a location about a mounting hole 28 thereof, and the head of a screw B for mounting a bearing 26 on the bracket side plate is made flush with an outside surface of the bracket side plate 16. The top plate 12 and the front plate 14 are seam-joined to each other by means of hooked engaging portions 41, 45.