| 摘要 |
PROBLEM TO BE SOLVED: To realize the joining of a light duct which is savable in executing labor and an installation space, and is excellent in sealing ability. SOLUTION: This is a structure where foaming material duct tubular bodies 3 for composing a duct system are mutually joined, and the joined ends of opposite foaming material duct tubular bodies 3 are provided with a hard male fit-inserted joining member 4 and a soft female fit-fixed joining member 5, and each of joining member 4, 5 has inner wall adherence parts 41, 51 which are previously fitted in the inner wall face of the joint end part and stuck to the inner wall face with an adhesive tape and flange parts 42, 52 which meet the adherence parts 41, 51 at right angles and abuttedly arranged on the end face of the joined end part. The inner wall adherence part 41 of the male fit-inserted joining member 4 is extendedly provided with a fit-inserted tongue piece part 43, and the inner wall adherence part 51 of the female fit-fixed joining member 5 is provided with a sandwichedly holding groove bottom 53 where the tongue piece part 43 is fittedly fixed, and the male fit-inserted joining member 4 and the female fit-fixed joining member 5 are mutually fitted for mutually joining and sealing the duct tubular bodies 3. |
