| 摘要 |
PROBLEM TO BE SOLVED: To provide a door body having high strength.SOLUTION: An indoor-side surface part 21 of a door body 2 includes a main surface part 210 and outer edge faces 215-218, and the thickness between an outdoor-side surface part 20 and the main surface part 210 is larger than the thickness between the outdoor-side surface part 20 and the outer edge faces 215-218. A frame structure of the door body 2 consists of a first frame 3 arranged between the outdoor-side surface part 20 and the main surface part 210 and a second frame 4 arranged between the outdoor-side surface part 20 and the outer edge faces 215-218. The first frame 3 and the second frame 4 are welded to each other, the first frame 3 is formed by welding horizontal frames and vertical frames made of channel steel in a four-side shape, and a plurality of middle bones 8 made of square steel tubes are arranged at intervals in the width direction of the door body between the outdoor-side surface part 20 and the main surface part 210. |
