GB724344A - Improvements in or relating to tools for use in the manufacture of heat-interchangers - Google Patents

Abstract

724,344. Punching. BRAUN, A. May 4, 1953 [March 5, 1953], No. 12235/53. Class 83 (4). A tool for producing multiple heat-interchanger gills with profiled (i.e. non-rectilinear) longitudinal edges is characterized by relarively movable sets of punch elements so formed and arranged that some elements produce tubereceiving holes in interposed sheet-metal stock and the others simultaneously divide the stock so formed with holes into a plurality of gillstrips having their profiled edges interdigitated. Gills of heat-interchangers are formed with zig-zag or wavy edges a, b and holes f, flanged at c, Fig. 2, to receive tubes. A tool for forming such gills includes a base member 1 and an upper member 2 movable theretowards. Flanging.-A plate 3 secured to base member 1 carries hole punches 17, the operative end of each of which is bevelled to form a sharp medial ridge co-operating with dies 18 carried by a plate 4 on the upper member 2. Spring- urged stripper plates 5, 6 are mounted on the plates 3, 4 respectively. Dividing.-Mounted on a plate 26 secured to the base member 1 are dividing punch elements 37, 38, 39 which co-operate with punch elements 36 mounted on a plate 27 secured to the upper movable member 2 to divide the stock, punched with holes, into a series of strips with zig-zag or wavy edges. Spacers 31 on a spring-urged plate 28 mounted on the lower plate 26 and spacers 35 on a spring-urged plate 29 mounted on the upper plate 27 are provided. The faces of the punch elements 36 and their co-operating spacers 31 are inclined relative to the plane of the stock. The faces of the elements 36 may be recessed as at 51 to clear the tube hole flanges c. The series of divided gills may be partly severed transversely on leaving the tool.