| 摘要 |
1450235 Bending JOHN LYSAGHT (AUSTRALIA) Ltd 6 May 1974 [15 May 1973] 19835/74 Heading B3E Flat sheet or strip is progressively profiled transversely to its length by intermittent advance between a pair of press dies of progressively changing shape along the direction of strip advance the die work surfaces being rectilinear in at least one direction. The advance may be effected manually or automatically, e.g. by ratchet mechanism operated by the withdrawal stroke of the dies. Fig. 6 shows progressive corrugating dies 33A, 36A, the strip moving between them from left to right. In a pair of dies for forming a semicircular section, Fig. 1 (not shown), the lower die is of the final section throughout, and only the upper die is cut away like die 33A. Figs. 13 and 15 show dies for forming a top-hat section, so shaped that the distance 54 between adjacent bends remains constant along the dies. Fig. 18 shows an embodiment in which a lower die 61 is supported above a base 59 by springs 60. At the entry end of the dies, the edges 57 of the strip are progressively bent to positions 56 by sloping parts 64 of the reciprocating upper die 58. Thereafter, further flanges 70 are formed by die 61 reciprocating against inwardly inclined surfaces 67 on bed 59. In another embodiment, Figs. 19-27 (not shown), another section having curled edges is made. |
