| 摘要 |
<p>There is disclosed a sealable louver, for permitting only the outward flow of air at a ventilation outlet. The louver comprises a frame having a plurality of laterally extending vertically overlapping slats. These slats are convex in cross-section relative to the outside, and are outwardly pivotable along an axis located at the upper edge thereof. The lower edge of an upper slat overlaps the upper edge of a lower slat, and abuts on the same at two surfaces of contact. These surfaces of contact prevent water, light rays and wind draughts from seeping inwardly therethrough. The frame is constructed of a frame member or members measured from an elongated extrusion having spaced notches allowing the latter to be bent at a right angle at each notch. A rectangular or square frame of any size may thereby be fitted to the dimensions of the ventilation outlet. The frame(s) can be made in sections.</p> |
