Patent GB-1039074-A (GB)
Title: Method and apparatus for joining strip
Inventor: SEELOFF MELVIN MAX
IPC: B21D39/03
Filed: 1965-03-16
Abstract: 1,039,074. Joining strips; welding by pressure; shearing. TAYLOR-WINFIELD CORPORATION. March 16, 1965, No. 11028/65. Headings B3A, B3R and B3W. An apparatus for joining overlapped edges of metal sheets comprises a pair of clamps 16, 17, Fig. 2 (not shown), a combined shearing and welding assembly 20 and means to move the assembly 20 longitudinally along the overlapped edges between the clamps, the assembly 20 comprising progressively acting shear means 27, 35 to separately shear the overlapped edges along offset lines while the sheets are held in the clamps and also comprising a pair of seam welding electrodes adjacent the shearing means to weld the sheared overlapped edges progressively and closely behind the shearing means. Framework.-A C-shaped frame 11 is slidably mounted on a base 10 and is moved by a screw 18. Also mounted on the base 10 are an entry clamp 16 and an exit clamp 17. Shearing means.-A carrier 23 for the shearing means is mounted for vertical sliding movement on a quill 21 controlled by a cylinder 22. Secured to the carrier 23 is an upper pad 24, Fig. 5 (not shown), which is joined by a Z- shaped section 25 to a lower pad 26. Integral with the section 25 is an anvil 27, which is tapered in plan and longitudinal elevation. In cross-section the anvil is generally flat and has a step on diagonally opposite side portions of the top and bottom to form an upper cutting edge 28 and a lower cutting edge 29. Disc cutting wheels 32 and 35 co-operate with the edges 28 and 29 respectively. The centre section of the anvil 27 and the edges of the discs 32 and 35 are faced with a metal carbide 30, 36. The cutting clearance between the discs and the anvil is adjusted by shims. Behind the discs are two guide blocks 39 and 40, Fig. 4 (not shown), which deflect the cut-off strips away from the welding electrodes 12 and 13, and also press the overlapped sheet edges together immediately before the electrodes make the weld. Welding means.-A transformer 14 supplies current to the electrodes 12, 13, the lower electrode 12 being adjustable vertically by a crank 15<SP>1</SP> to compensate for wear. The upper electrode 13 is adjustable vertically by a cylinder 15 which also supplies the pressure to form a mesh seam weld. The surfaces of the electrodes are continuously re-conditioned by pneumatic hammers 19. Operation.-With the assembly 20 in the retracted position as shown in Fig. 1, a sheet which has been running through the apparatus is stopped as its trailing end approaches the weld line, and is gripped by the exit clamp 17. The assembly 20 is lowered by the cylinder 22 so that the tip of the anvil 27 overlies the strip. A new sheet is then fed in until its leading end abuts the clamp 17 and it is gripped by the entry clamp 16. The assembly 20 is then traversed by the screw 18 and the anvil 27 slides between the sheets and both sheets are cut as they engaged by the discs 32 and 35. The sheared overlapping edges are pressed together by the blocks 39 and 40 and welded by the electrodes 12 and 13. In a modification the anvil 27 is split longitudinally, Fig. 6 (not shown). One half 27<SP>1</SP> is carried by an upper slide 41 which also carries the upper disc 42, and the other half is carried by a lower slide 43 which also carries the lower disc 44. By this arrangement the amount of overlap can be readily adjusted. In a further modidification, Fig. 10 (not shown), the disc cutters are replaced by air-operated reciprocating cutters. In a third modification the cutters are mounted so that the shearing operation can be performed when the leading end of the new sheet is either over or under the trailing end of the old sheet. A first method of achieving this comprises mounting the shearing unit so that it is rotatable about an axis parallel to the direction of travel of the sheet and in the plane thereof, Figs. 8 and 9 (not shown). In a second method of achieving this the anvil 27<SP>11</SP>, Fig. 7 (not shown), has two transversely spaced cutting edges on both its top and bottom surfaces and right and left shear knives 32<SP>1</SP>, 32<SP>11</SP> and 35<SP>1</SP>, 35<SP>11</SP> are mounted on rocking arms 47.