| 摘要 |
A ventilation device for mounting in a wall of a building includes a supporting framework adapted for mounting in the wall and forming an air flow passageway for flow from the exterior of the wall to an opposite side. A vent flapper is pivotally mounted in the framework for selective movement within the framework between a closed position where air flow through the passage is prevented and an open position where air flow is allowed. Thermal insulation material is fixedly mounted on or in the vent flapper and is arranged to extend across the air flow passage in the closed position of the vent flapper. A handle can be mounted on an interior-facing side of the flapper for moving it between the closed and open positions. An exemplarily version of the device includes a vent cover mounted on the supporting framework at an exterior end of the air flow passage. |
