Patent GB-940722-A (GB)
Title: Method of and apparatus for bending pre-formed wire
Inventor: GONIA AUGUST THOMAS
IPC: B21F35/00
Filed: 1961-07-20
Abstract: 940,722. Bending. ROCKWELL-STANDARD CORPORATION. July 20, 1961, No. 26303/61. Heading B3E. A machine for twisting a loop-connecting portion of a preformed sinuous wire strip, comprises a frame, a rotatable wire - twisting head mounted on the frame and adapted to embrace a loop of a sintus wire strip, means mounted on the frame to hold against rotation an adjacent oppositely opening loop of the strip from that engaged by said head and at the opposite end of the loopconnecting portion connecting said adjacent loops, actuating means for rotating the head to twist the said loop-connecting portion, and distortion-connecting means on said head including a member controllably moved to abut the bight portion of the loop embraced by the head and during rotation of the head urge the bight portion of the loop in a direction tending to close the angle between the bight portion and the loop-connecting portion being twisted. Preformed wire strips S, shown in detail in Fig. 24, are fed one at a time from a magazine M, the bottom-most strip being pushed therefrom by a finger 88, Fig. 2, to drop by gravity to a position WBP<SP>1</SP> where it is temporarily supported by surfaces 376 on anvil heads 372 on shafts 362 rocked to the supporting position by hydraulic means and also supported by a finger 498, Fig. 1, on the shaft 362. The shafts 362 are then rocked to drop the strip S to position WBB where it is supported on die members 402, Fig. 2, crimper units 340, 342, 344, 346, Fig. 1, and on a plate 508 at one end with a loop L1 around a pin 512. A hook member 516 engages a loop L18 at the other end of the strip and is pulled to the right, Fig. 9, to position the strip properly, such movement completing an electric circuit which allows the continued operation of the machine. Shafts 408, Fig. 2, driven from an electric motor, of the crimper units 340, 342, 344, 346, then rotate to cause eccentrics 406 thereon to rock dies 412, moved into position by a crank 420 on a fluid-pressure driven shaft 426, so that dies 404, Fig. 3, thereon co-operate with surfaces 378 on the suitably positioned anvil heads 372 to crimp or bend the strip at K1, K2, K3, K4, Fig. 28. Twister heads T160, T170, T172 are then moved inwardly, by fluid pressure cylinders 302, Fig. 6, so that transverse grooves thereon embrace loops of the strip S and a holder H162 is moved in, by a fluid-pressure cylinder 200, to embrace a loop in the strip. Twisters T160, T172 then are rotated, by rack- and-pinion means 316, 318, driven by fluid pressure means 308, so as to bend opposite ends of the strip upwardly. Twisters T160, T172, holder H162 and anvils 372 then retract and twister T164 and holders H166, H168 and a crimper 466, Fig. 1, move forward to engage the strip. Twisters T164, T170, then rotate to bend the strip and the crimper 466 is actuated to form a bend K5 in loop L14. The crimper 466 comprises, Figs. 11, 12, a fixed anvil block 474 with a notch 488 therein co-operating with a die 492, on a twister shaft 468, which has a portion 494 thereon urging the loop L14 into the notch 488. Crimper, holders and twisters then retract and the strip is allowed to fall from the machine. A loop L16 may be bent at K6 by a pair of twisters T174, T176, Fig. 17, jointly embracing the loop 16, when the twister T176 rotates. T176 is then withdrawn and T174 rotated to straighten the wire portion L15- L16. To correct for distortion fixed cam-plates 248, Fig. 20, urge pins 244 in the twister heads against the wire therein. The pins 244 also serve to eject the strip as the heads are retracted. Also to offset distortion wire engaging parts 224, 256, Fig. 19, of holders and twisters may be offset from the axis of twisting. Specification 940,721 is referred to.