| 摘要 |
<p>The ventilator comprises an open-ended box, (1) moulded from a plastics material and provided with pivoted (2) top and bottom and convex sides (4) for swivelling. Inside the box are air flow direction blades (6), also moulded from plastics as a single unit. All the blades within the box and their innermost edges are joined together by a common connecting bar (7). The blades are manipulated by a lever (8) at the front, forming part of a blade. Blades are hinged (9) to the bar and the lever by sections of plastics which are thinned down to be flexible.</p> |
