GB837105A - A method and means for press-forming articles - Google Patents

Abstract

837,105. Shaping cup-like articles. ROSE VALE MANUFACTURING CO. Ltd. Feb. 28, 1958 [Feb. 4, 1957], No. 36363/56. Class 100(2) Articles such as cups, confection holders and milk bottle caps requiring different depths of draw are formed from soft material, e.g. aluminium foil, in a single press of constant stroke wherein a plurality of die sets is arranged to work on the same sheet of material, each set being for a different size of article, and as each smaller article is completed the die parts therefor yield to allow the completion of the next larger article during the same stroke of the press. Each die set comprises a male part including a tubular member 1, carrying a blanking tool 7, and a male former 4 both secured to the movable head 3 of the press, a collar 5 being slidable between the parts 1 and 4 and biased downwards by a spring 6. The female part of each die set includes an annular member 8 mounted on the fixed head 10 of the press, a resiliently mounted female former 11 concentric therewith and biased upwards by a spring 12, and an ejector 15 biased upwards by a spring 16. In the die set for forming the largest article the spring 12 may be omitted and the former 11 may be fixedly mounted. A strip of foil x is fed intermittently between the die parts. As the press closes the tool 7 cuts out a blank in co-operation with the annular member 8, the blank is gripped between the collar 5 and the face 11b of the female former 11, and the male former 4 draws the blank into the female former, forcing back the ejector 15 as it does so. The strength of the spring 12 is such as not to yield under the pressures necessary for carrying out the forming operation but to yield if the male die part continues to move downward after the forming operation is complete. Thus as each of the smaller articles is completely formed its female former 11 is in turn depressed against its spring 12 as the head 3 continues to move downwards until the largest article has been formed. The head 3 is then raised and stripper rings 17 push the waste foil off the tools 7, the finished articles being ejected on to a shoot by the ejectors 15. In modifications the male former 4 may be resiliently mounted as well as or instead of the female former 11. Also the positions of the male and female formers may be reversed, the latter being mounted on the head 3 within the tubular member 1.