GB1394915A - Fastening together of sheets of deformable material - Google Patents

Abstract

1394915 Jointing; punching O P HAFNER 11 July 1973 [28 July 1972] 32955/73 Headings B3J and B3W A joint is formed between sheets of metal or other deformable material 28, 29, Fig. 5, by displacing areas 128, 129 of the sheets located between cuts through the sheets so that area 129 is beyond sheet 28, and spreading the area 129 laterally beyond the edges of the cuts in sheet 28 and also beyond the edges of the displaced area 128. As shown, the punches 80, 92 and die 70 for striking out the tabs 128, 129 are similar to those in Specification 1,343,003 to which reference is made, but the press is different and operates so that during squeezing of the tabs between the punches 80, 92, the upper tab 128 is prevented by the die 70 from spreading laterally. A layer of another material may be interposed between the sheets. The press has a casing 24 in which an outer ram 50 carrying the die 70 is driven by connecting rods 31, 33 on eccentrics 21, 23 fixed to a drive shaft 10. An inner ram 392 carrying the flattening punch 92 is independently driven, through an adjustable connecting rod 32, 44, by an eccentric 22 which is adjustably coupled to a collar 34 on the shaft 10 by a pin 37 engaging one of a number of holes 36 in the collar. Thus phase relationship between operations of the flattening punch 92 and the surrounding die 70 can be changed by selecting a different hole 36 for the pin 37. The position of the stroke of the punch 92 can be changed by altering the length of the connecting rod 32, 44, the parts of which are connected by a bolt 45, Fig. 2, which may be turned, after releasing a clamping screw 49, by engagement with sockets 245. The die 70 also is adjustable, by means of its holder 62, which engages a timeadjustment nut 55. Thrust on the die-holder 62 is transmitted through a bearing nut 65 with coarse threads. A urethane stripper 81 surrounds the lower punch 81 which may also be adjustable.