| 摘要 |
<p>A roof ventilating device (D) has a roofing slab (1) with a dome (2) provided with a top opening for a ventilating pipe (5) whose diameter approximately corresponds to the width of the dome (2) and is smaller than its length. A cap (6) that covers the dome (2) has a vent. In order to optimise the operation and the construction of the device, the vent in the cap (6) comprises a ventilation grid (9/Ö) that extends beyond the opening of the ventilating pipe. The larger, longitudinal diameter of the ventilation grid (9/Ö) runs into the circular cross-section of the ventilating pipe (5) through funnel-shaped (funnel T) sliding surfaces (13, 14).</p> |
