| 摘要 |
PURPOSE: To prevent the entry of raindrops even at the time of a stong wind by providing a blind plate for forming ventilating passages at right and left sides of a ventilating hole so as to connect the ventilating hole to outsid and a ventilation preventing structure provided in the ventilating passages for preventing the ventilation, in cooperation with a main body frame plate. CONSTITUTION: Since the front face of the ventilating hole 25 of a main body frame plate 20 is blocked with a blind plate 30, and upper and lower parts are blocked with an upper frame plate and a lower plate, air only passes through right and left ventilating passages 70 and reaches the ventilating hole 25. While air entering laterally from the ventilating passages 70 is blocked with a ventilation preventing structure 75, it flows in winding ventilating passages 70. Raindrops entering together with the air collide with the barriers 35 and 23 or the like of the ventilation preventing structure 75 and flow down owing to gravity. The air flows horizontally, so that the raindrops are hardly blown into the ventilating hole 25 without interrupting them. Thus, when a strong wind blows, the raindrops can be prevented from being blown into an interior from the ventilating hole by decreasing a wind pressure to the ventilating hole or making it negative pressure. |
