| 摘要 |
<p>A duct (2.1) passes through a roof from below and terminates in a lower section of a space enclosed by a coupling (1.2). A connector surface (2.3) extends from a lower piece of the inside of the coupling's interior towards an outer surface of the duct. On the lowest lying contact area of the connector surface with the coupling surface, the coupling surface is pierced by an outlet opening (1.5).</p> |
