| 摘要 |
PURPOSE:To facilitate an opening or closing operation of a ventilation operation and improve a convenience for use of the device by a method wherein a vane to open or close the ventilation port is operated from both sides of the ventilation port. CONSTITUTION:When a resilient engaging part 7 is placed at a groove part 8a, a vane 3 is positioned at a central part of an inner side surface, and a ventilation port 1 is opened. As the vane 3 is pushed from a front side as shown by an arrow A, the resilient engaging part 7 passes from a groove part 8a through a groove 8b and moves toward one end 19 of the groove 8c. As a hand is moved off the vane 3, a movable part 6 is returned by a recovering force of the resilient member 5 and the resilient engaging part 7 is struck against the engaging part 9. Under this condition, the edge part of the vane 3 is struck against a rear side flange 2b and then the ventilation port 1 is closed. As the vane 3 is pushed from a rear side indicated by the arrow B, the resilient engaging part 7 passes through a groove 8f, moves toward one end 21 of a groove 8g. As the hand is moved off the vane 3, similarly, the resilient engaging member 7 strikes against the engaging part 10 with a recovery force of the resilient member 5. Under this condition, the edge part of the vane 3 strikes against the front flange 2a and then the ventilation port 1 is closed. |
