To provide a duct excellent in silencing property to be used for transferring or ventilating air for heating and cooling.
The duct includes a cylindrical duct wall 4 and a reinforcing body 6. The reinforcing body 6 is spirally wound at a prescribed interval on the duct wall 4. The reinforcing body 6 is welded to the duct wall 4. The duct wall 4 includes an inner layer 8, a foam layer 10 and an outer layer 12. The outer layer 12 includes a second air-permeable sheet layer 28 and a film layer 30. The base material of the film layer 30 is a thermoplastic resin. The base material of the reinforcing body 6 is a thermoplastic resin. The film layer 30 is melted by heat imparted when welding the reinforcing body 6 to the duct wall 4 which results in the formation of an exposed portion 32 on the duct wall 4 near the reinforcing body 6. In the exposed portion 32, the air-permeable layer 28 is exposed. Air in the duct can be transferred to the outside through the exposed portion 32.
| JPH10227379A | 1998-08-25 | |||
| JP2009138792A | 2009-06-25 | |||
| JPH11190492A | 1999-07-13 |
Sumitomo Norio
Kuroyoshi Murohashi
Hiroshi Kasakawa