| 摘要 |
<p>A ventilator for use with sheet metal roofing either of the batten type using elongated pan sections or flat sheets. In a preferred form of the invention using sheet metal pan sections between battens, the pan sections are lap-joined at the ridge of the roof and a ventilator opening is cut in the overlapped end portions of the pan sections and in the underlying roof on either side of the ridge of the roof. The base member of the ventilator is formed from a single sheet of metal and has a central opening coinciding with the opening in the pan section. The edge portions of the central opening in the base member of the ventilator are upturned to form side walls defining the ventilator opening and a screen is fitted into the opening. Downwards of the ventilator opening, on each side of the ridge of the roof, the lower edge portions of the base member are folded back on themselves in curved form to form wind breakers extending between battens of the pan sections. A cover member for the ventilator is secured to the top surface of the battens on either side of the ventilator and the lowermost edges of the cover are bent downwards and backward on themselves to form troughs between battens and combine with the wind breakers to form offset air passages between the interior of the ventilator and the exterior of the roof, with the wind breakers having a suction effect to draw air outwards from the interior of the roof.</p> |
