| 摘要 |
The method employs an endless belt (10) running around two pulleys (12a,12b) fixed to the ceiling. The sheath (1) of textile material or plastic film is fixed to the outlet pipe (3a) of e.g. a ventilator (3), and guided by supports (8) movable along one or more cables (9). The leading support (8a) is bonded (11) to the belt enabling sections of the duct to be unfolded or refolded back on one another. The belt is driven by a motor or manual control (7) coupled to one pulley (12a). |
