Patent GB-1011988-A (GB)
Title: Wire bending machine
Inventor: DENNISON VINCENT
IPC: B21F1/00
Filed: 1963-03-14
Abstract: 1,011,988. Bending and corrugating wire and rod. SLUMBERLAND GROUP Ltd. March 13, 1964 [March 14, 1963], No. 10111/63. Heading B3E. A wire bending machine for use, for example, in making castellated form spring elements for car seats, comprises a bending tool having an eccentric pin or roller mounted on a spindle and arranged to engage and bend a wire or rod element against a forming tool on rotation of the spindle between feeding movements of the element, the feed being controlled to vary the spacing between bends. A pneumatically operated machine for bending a number of wires 10, simultaneously in one plane in the same or alternate direction, comprises a headed and splined spindle 11 vertically displaceable by pneumatic means 40 during each return stroke, having an eccentric bending pin 13 about which is pivoted a roller 14, the spindle being oscillated to bend the wires about forming tools 15 by a sprocket 33 driven by a chain 32, the ends of which are attached to single acting cylinders 29, 30 arranged on each side of an endless feeding chain 24. Identical lengths of spring wire 10 are gripped at one end by a jaw 18 of a saddle 17 slidable along a horizontal slide 16 whilst the other ends lie between the tools 15. The saddle is intermittently advanced to feed the wires by the chain 24 actuated by a double-acting pneumatic cylinder 26 and a spray 22 of a oneway ratchet mechanism until an arm 21 thereon abuts a dog of a rotatable feed control drum 19 to stop further movement thereof. The control valves of the pneumatic circuit are so arranged that alternate operation of the cylinders 29, 30 successively bend the wires in alternate directions as they are fed stepwise under the control of preset dogs 20 of an indexed drum 19. If the bends are required in the same direction then the corresponding dogs on the drum are arranged at the same axial position so that the bending tool carries out an idling stroke prior to the feed stroke and next forming stroke. The stroke of the bending cylinders and hence the angle of bend is controlled by extensions of the piston-rods thereof contacting adjustable stops 45 carried by discs 46 which are alternately rotatably indexed by rack type ratchets 48 actuated by double-acting pneumatic means so that actuation of the left hand cylinder causes indexing of the right hand disc &c. The drum 19 is indexed with each feed stroke of the feed cylinder 26. Actuation of the stop 45 by the rod 31 moves the disc 46 slightly rearwards to trip a valve which energizes the opposite bending cylinder. Initially, the sprag 22 is disengaged from the chain 24 and the saddle moved to the datum position. The bending pin 13 is retracted clear of the formed wire and positioned on the appropriate side of the centre line bisecting the tools 15 in readiness for the next bending operation during the wire feed stroke. The discs 46 may be manually set by hand wheels 68. The sequence of operation is initially manually started and subsequently sequence controlled by a pneumatic circuit comprising trip and shuttle valves, Fig. 5 (not shown). Alternatively, the system may be controlled by hydraulic or electric means.