| 摘要 |
PURPOSE:To contrive the effective reduction of noise in a ceiling ventilating fan, provided with a guide member for guiding suction air. CONSTITUTION:A fan casing 5, having a bell mouth 6 on a lower plate 5a, is provided in an outer frame 1 in a ceiling while a centrifugal fan 10, driven by a fan motor 9, is provided in the fan casing 5. A guide member 11, equipped with a tapered surface unit 11b for guiding suction air toward the bell mouth 6 so as to flow smoothly, is provided below the lower plate 5a of the fan casing 5. The mounting part 11c of the guide member 11 is provided so as to be projected upwardly than the upper end rim of the guide member 11 whereby a gap S, having the size of 2-15mm, is formed between the guide member 11 and the fan casing 5. |
