To simplify works for attaching an upper door leaf by a method wherein a first hinge structural part is provided at a left frame member of a square frame and a second hinge structural part is provided at a left frame member of a door leaf frame.

A storage 2 having an upper door leaf 5 is housed in a hollow part 3 for putting the storage therein of a floor 1. A first hinge structural part 12 is provided at a left frame member 11 of a square frame 10 attached to the upper end opening 3a of the hollow part 3, and a second hinge structural part 22 is provided at a left frame member 21 of a door leaf frame 20 attached to the upper door leaf 5. When the upper door leaf 5 is shut, the second hinge structural part 22 is fitted into an indent 19 of the first hinge structural part 12, and a leftwardly projecting part 23 at the second hinge structural part 22 side is engaed with a guide part 14 at the first hinge structural part 12 side. On the other hand, under the state after the upper door leaf 5 is opened at an angle of 100°, a downwardly projecting part 16 at the front end of a rightwardly projecting part 13 of the first hinge structural part 12 is fitted into an indent 29 of the second hinge structural part 22, and an upper projected part 26 of the second hinge structural part 22 and a lower projected part 16 are engaged with each other to serve as a stopper.