Improvements in or relating to apparatus and methods adapted for use in soldering the side seams of cans

摘要

945,241. Making cans; soldering. BRITISH UNITED SHOE MACHINERY CO. Ltd. Feb. 12, 1960 [Feb. 19, 1959], No. 5043/60. Headings B3A and B3R. In soldering the side seams of can body portions, each of which side seams comprises an interlocked portion joining two lap portions comprising overlapping layers, the body portions are conveyed seriatim past solder-applying mechanism and pressure is applied to the lap portions only of the side seams to hold the layers together while the solder between the layers is allowed to solidify. The cylindrical can bodies B, Fig. 5, made of tin-coated steel, each have an interlocked side seam portion 4 extending to within a short distance of the ends of the body and at its ends lapped portions L for facilitating the fitting of the can top and bottom. The bodies are conveyed from a body maker seriatim with their seams lowermost and in alignment by dogs 28 on an endless chain 26 past a solder applying mechanism S substantially as described in Specification 900,716 and the lap compressing mechanism C. The chain 26 is supported in guides 36 by transverse studs which allow a slight upward movement against applied pressure. The mechanism C comprises an endless chain 42 having lugs 44 with the same spacing as the dogs 28, the chain 42 having the same linear speed as the chain 26 and being supported by a guide 46. The mechanism C also comprises two spaced guide members 60 which engage each body portion on each side of its seam as it passes through and leaves the solder applying mechanism S and two similar guides 64 at the exit end of the chain 42. The body portions passing along the guides 60 are deformed to elliptical shape with no gap between' the lapped portions 14, 16, Fig. 5, and while still on the guides 60 a trailing lap portion LSP1/SP, Fig. 3, of one body and a leading lap portion LSP2/SP of the next body are engaged by the flat upper surface of a lug 44 on the chain 42 which maintains the elliptical shape. As the bodies are carried by the chains 26, 42 the solder solidifies and then the bodies move on to members 64 which allow them to return to cylindrical shape. The lapped ends of the soldered bodies are flanged outwardly and rolled with edges of can top and bottom members to form double seams.