| 摘要 |
<p>PURPOSE: To provide an air duct which can uniformly release air by winding in partially doubling manner an impermeable film on the outer surface of the main body made of permeable materials formed in a pipe shape, and using this doubling part as a valve mechanism. CONSTITUTION: The main body 1 is formed in pipe shape and is made of permeable materials, and it is so constituted that the air passing through its inner spaceαcan be released into outer space. An impermeable film 2 is wound on the outer surface of the main body 1. The film 2 is partially doubled wound on the outer surface of the main body 1, the doubled part 3 and its neighbor area 1 is not adhered to the main body 1, the end of the doubled part 3 becomes a free end 4. This free end 4 functions as a valve to release the air of the area intoαthe outer space.</p> |
