Retractable canvas roof for sports hall - is draped over parallel interspaced beams which pivot about long base edge to vary canvas tension

摘要

The retractable roof is used on sports halls. It has a single or composite canvas cladding (3) draped over beams (6) which pivot to vary th canvas tension. The beams span the short dimension of the roof opening, sited at definite centres on the long roof axis when deployed, and pivotable about one longitudinal base edge (15) by jacks (16) operating on the opposite edge. The beams are arched longitudinally to provide drainage falls for the concave canvas bays between. The jacks (16) also act as shock absorbers when differential wind generated pressures occur. Double wheeled (12, 13) trollies (11) locate the beam ends, and are coupled together by draw bars (14). They travel on rails along the longitudinal edges of the roof opening. When retracted the beams tilt and fit together for storage.