Patent GB-940721-A (GB)
Title: Machine and method for bending pre-formed sinuous wire
Inventor: GONIA AUGUST THOMAS
IPC: B21F35/00
Filed: 1961-07-20
Abstract: 940,721. Twisting; angular bending. ROCKWELL-STANDARD CORPORATION. July 20, 1961, No. 26302/61. Heading B3E. A method of twisting the straight-wire loopconnecting portions of a preformed sinuous wire strip comprises gripping adjacent oppositely opening loops at opposite ends of the straightwire portion to be twisted connecting such loops, and rotating one of the loops either, about the axis of the straight-wire portion, or about an axis parallel with but offset from the axis of the straight-wire portion, or about an axis inclined to the plane of the strip, while holding the other loop stationary. Preformed wire strip 23, Fig. 23, is placed in a trough 82, Fig. 2, where it is supported on a bottom wall 110. A wire strip locator L, Figs. 7, 8, 9, pivoted to the machine frame at 182, is then swung down by fluidpressure means 150 so that a series of V blades 156a-156e carried by the locator engage and position the transverse or tension portions of the wire strip, a positioning blade 216 cooperating with a block 217 locating the righthand end of the strip. Thereupon wire twisting heads T218, T220, T222, T224, T226 and T228, wire holding heads H230, H232, H234, H236, H238 and crimping heads C1, C2 and C3 are moved in from the sides of the trough to engage the wire strip. The wire twisting heads T, Figs. 16, 18, are each carried by a sleeve 258 moved axially by a lever 252 operated by fluid pressure means 253. A jaw-actuating rod 274 extends through the sleeve 258 and towards the end of the forward movement of the sleeve a spacer 310 on the rod 274 engages a stop 288 and causes jaws 280, 282 to close on the wire strip as the sleeve 258 completes its forward movement. Wire loop locating pins 334, 336, Fig. 20, are provided on one of the jaws. The twisters T are rotated by a rack 265 engaging teeth 267 on the sleeve 258 and reciprocated by fluid pressure means 273. The holders H, opposing the twisters T, are similarly moved forwards but are not rotated. After the twisters T and holders H have engaged the strip the locator L is moved away and the end twisters T218, T228 are rotated to bend up the ends of the strip, the adjacent loops being held by the holders H234 and H232. At the same time the crimpers C1, C2, C3 are actuated to bend the bights of certain loops of wire at points 364, 366 and 368, Fig. 6. Each crimping head 468 is supported by a pair of arms 448 carried by a plate 370 or 372 which are rocked, to bring the crimping heads in operative position, by a fluid pressure means 414 operating through links 424, 428, 432. The crimping heads 468 include a jaw 494, Figs. 11, 12, 14, on the arms 448 and a movable jaw 486 is carried by a plate 478, pivoted at 502 to the arms 448, and rocked by fluid pressure means 454 to crimp the wire. The twisters T218, T228 and their opposed holders are then withdrawn and the crimpers C1, C2, C3 are released, and twisters T220, T224 are rotated to bend the strip. They and their opposed holders and the crimpers are then withdrawn. Twister T226 and twister T222 are then rotated, the first in co-operation with holder H230 and the second which does not co-operate with a holder bends the wire at 512. The twisters and holder are then retracted and the bent wire removed. The axis A of the twister, Fig. 20, may be aligned with the axis of the straight wire portion 340 to be twisted or may be offset therefrom and parallel thereto or may be inclined to the plane of the wire-strip, to compensate for distortion.