| 摘要 |
PURPOSE:To prevent polluted air from being leaked out of a main body of a ventilation fan for a duct to a surrounding air and to prevent dew formation water generated at a duct connection part from being dripped onto a ceiling plate and the like. CONSTITUTION:An opening 8 is formed at one side surface having a discharging port 3 of a main body 1, thereby discharged air leaked between the main body 1 and a vertical plate 10 is recovered through the opening 8 into the main body 1 kept at a negative pressure. A recessed part 11 is disposed at an outside position of a duct connection part 9 of the vertical plate 10a and an opening 8b is disposed at one side surface of the main body to perform a positive recovery of polluted air. A recessed part 11a is disposed at an outside position of a discharging port 3b at one side surface of the main body 1, the recessed part 11a is provided with the opening 8b, thereby the leaked air is positively recovered and at the same time a planar accuracy of one side surface is improved to cause an air leakage between the main body 1b and the vertical plate to be reduced. In addition, an opening 8c is provided from the lower position of the discharging port 3c of the recessed part 11b at one side surface to an abutting position of the vertical plate 10 and then the dew formation water is positively recovered. |
