| 摘要 |
PURPOSE:To simplify duct work and prevent the chattering sound of a shutter by forming a duct connecting joint incorporating a shutter therein to a specified configuration. CONSTITUTION:The duct connecting joint 6 which is tapered so as to be fitted into the duct 112, is attached to a duct mounting member 4 closely attached to the main body 1 of the ventilating fan so as to surround the opening 5 of the duct mounting member. The shutter 8 is attached to cut-ups 7 in the duct connecting joint 6 by pins 110 and is opened by being rotated about the pins 110 toward the direction of the duct 112 until it is held substantially horizontal when air is discharged while it returns to a vertical state due to gravity when the fan stops. The duct connecting joint 6 has a sufficient length such that the top end of the shutter does not project outside when the shutter 8 is opened to become horizontal and therefore, the shutter 8 does not run against the inner wall of the duct 112 generating a chattering sound and against the duct 112 even when the duct 112 is bent at right angles at a place near the duct connecting joint 6 whereby the shutter opens and close at a predetermined angle at all times. |
