| 摘要 |
<p>A back-air blocking device to ventilate a motor vehicle's inside space includes a frame or housing made of a first plastic, and a valve flap, made of flexible material, connected in one zone to the frame and in other zones resting against a sealing surface of said frame when the flap is in its rest position. The flap detaches off the sealing surface when subjected to a pressure differential. The valve flap is a thin plate made of a closed-pore, foamed material.</p> |
