| 摘要 |
<p>PURPOSE: To provide a ventilator which can surely seal up air and intercept light, by surely engaging a louver rotation stop member provided closer to the rear free end section of the bottom louver of a backframe than the front free end section of the louver with louvers. CONSTITUTION: Attaching tabs 52 are provided on the top louver 32 of a backframe 14 so that the tabs 52 may get in top tab openings 48 when the backframe 14 is engaged with a housing 12. Each tight closure member 10 provides a stop surface which is engaged with the lowest end section 101 of a bottom louver 94, and a closed surface 102 extended perpendicularly from the top louver 32 of the backframe 14 is extended toward a bottom louver 38 in the vertical direction over the full length of the top louver 32. When the top louver 32 is closed, the forwardly extended edge section 98 of the louver 90 is surely engaged with the closing surface 102 and intercepts the flow passages of air and light.</p> |
