Arch forming assembly
AssigneeCanadian Patents and Development Limited
InventorsLeslie T. Russell, George M. Proctor, William H. Bowes
Life of this patent
Estimating the term…
Abstract
A collapsible arch forming assembly comprising a flexible member and two tension line lengths with one tension line length threaded through even number guides, counted from one end of the flexible member and the other tension line length threaded through the odd number guides. Tensioning the tension line lengths arches the flexible member into the arch and this may be done by a winch assembly or inserting spreader bars at the guides to deflect the free one of the first and second tension line lengths at that position. The spreader bars may be replaced by, for example, mechanical jacks or fluid pressure actuated jacks particularly for such applications as using the arch forming assembly as formwork upon which concrete is poured.
Claims6
An arch forming assembly, comprising:
- (a) a substantially flat flexible member for bending to the shape of the curved arch,
- (b) a plurality of tension line guides attached to the flexible member at spaced intervals to a side of the flexible member which will define the inside of the arch so that tension line guides will be spaced therearound,
- (c) a first tension line attached at one end to a first side portion of the flexible member and threaded through even number tension line guides only, counted from the said first side portion to a second side portion opposed thereto, and attached at the other end to the second side portion,
- (d) a second tension line attached at one end to the first side portion 10 of the flexible member and threaded through odd number tension line guides only, counted from the said first side portion towards the said second side portion, and attached at the other end to the said second side portion, and
- (e) means for tensioning the said first and second tension lines to bend the flexible member to the shape of the curved arch.
Dependencies are inferred from the claim text.