Self-supporting cold frame - has frame topside reinforced by corrugations, and top edge arched upwards

摘要

The self-supporting cold frame is of transparent plastics material. The top of the frame is reinforced by transverse running corrugations of a depth which reduces from the middle outwards according to the reducing bending moment run. The top edge (5) of the frame is arched upwards in the longitudinal section to improve the reinforcement. The bottom edge of the frame has a proud edge and the further edge has plates, which project alternately vertically downwards and alternately horizontally.