| 摘要 |
804,575. Stamping. CARBODIES, Ltd. Jan. 29, 1957 [Feb. 23, 1956], No. 5591/56. Class 83 (4). A method of pressing sheet-metal to non- planar form, e.g. cupping, involves using a pair of press tools 10, 11 having respectively a peripheral ridge 12 and a coacting recess 14 for forming a peripheral channel in the sheet 18 to hold it in stretched condition while the coacting dies of the tools carry out the pressing operation, the outer wall 21 of the ridge coacting with a resiliently-supported, e.g. spring-loaded, annular member 19 to grip a marginal portion of the sheet prior to the pressing operation. The side walls 16 of the ridge and the side walls 17 of the recess are spaced apart by an amount less than the thickness of the sheet. The annular member 19 may be adapted to lift the pressing out of the lower tool 10 after the pressing operation. Alternatively, the member 19 is supported by a pneumatic piston and cylinder. In a modification, the annular member 19a (Fig. 3) is supported by bolts 26a attached to marquettes 31 and the tool 11a has a downwardly-depending portion 32, the lower surface 33 of which cooperates with the member 19a to grip an outer portion 35 of the sheet. Thus the sheet is gripped between three different sets of surfaces. Specification 804,574 is referred to.
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