| 摘要 |
<p>The collapsible roof, which can be folded up, is esp. suitable for protecting building sites from weather. It has three adjustable-length supports converging in a single point, where a conical screen is suspended. A pipe (3) which can be filled with fluid held under pressure, is attached to its bottom edge. The fluid may be water, pref. with an anti-freeze medium as an additive. The screen may incorporate a hole (6) as a gap for crane operation, the hole oval with a covering plate. One support (5) can have a lug formed onto its top end, pointing vertically upwards.</p> |
