Patent GB-1136364-A (GB)
Title: Automatic linking machine
Inventor: CRAFFORD THOMAS J
IPC: B21L11/00
Filed: 1967-09-02
Abstract: 1,136,364. Angular bending. CRAFFORD TOOL & DIE CO. 2 Sept., 1967, No. 40206/67. Heading B3E. An apparatus for linking a wire ring to a preformed element comprises a base, a vertically movable carrier mounted on the base, means for raising the carrier at pre-determined intervals, means for retaining and feeding a plurality of wire sections to a forward end of the carrier, means responsive to raising of the carrier to move the forwardmost wire section to an assembly station, a head assembly connected to the base and including a vertically movable die, and an actuating device to move the die downwardly to form a wire section at the assembly station into a wire ring. The apparatus includes a base 11 along which a cam assembly 12 is reciprocated by single-acting pneumatic cylinders. The cams are straight bars 14 and 16 which have sloping end faces. The carrier 18 is guided for vertical movement relative to the base and has roller followers 24 and 26 which run on the cams. Above the carrier 18 and fixed relative to the base is a top-plate 50 on which is mounted a magazine assembly 46, which includes a front channel block 52 and a rear channel block 58, both bolted to the top plate and forming between them a space which is occupied by a blade holder 66, a rear channel insert 68 and a holder 70 therefor. The blade holder 66 is generally rectangular and has secured to it, two wire cutting blades 80, 82 which have inclined, grooved upper edges. The holder 66 has a shank 84 which is locked in a hole 42 in the carrier by a bifurcated pin 146. The holder 70 is bolted to the top-plate 50 and has a slot 71 which receives the rear channel insert 68. This insert has a tongue 98 which projects through a slot 74 in the knife-holder 66, and a slot 96 which has a rounded bottom. Mounted on the front channel block 52 is a front channel insert 100 which has a similar slot 102, and secured to the insert 100 is a plate 110 which is integral with an arbor 112, and which at one end projects through the holder 66 and into the rear channel insert 68. The arbor 112 and the roundbottomed slots in the inserts define between them a U-shaped magazine channel. A stripper plate 99 adjacent the cutter blades 80, 82 has a U-shaped tapered slot 101. A wire is fed across the cutter blades and the piece cut off by upward movement of the blades is bent to U-shape around the arbor 112. A pusher mechanism including a cam 162 and a transfer blade 160 moves the newly-formed piece through the stripper 99, the taper on the slot 101 preventing the piece being drawn back by friction. Attached to the front face of the front channel block 52 is a plate 118 in which is a slot 120. A pusher blade 122, which is secured by a screw 123 to the carrier 18 slides in the slot and is retained by a cover-plate 116 and a clamping screw 130. Above the base is an over-arm 180 on which is mounted a vertically reciprocable die member 200 which is adjustable horizontally and vertically by screws 202, 204 and 206. The die is mounted on a sliding block which is biased upwardly by a spring and moved downwardly by a cam generally similar to the cams 14 and 16 and reciprocated by a doubleacting pneumatic cylinder. At each cycle of the machine, a length of wire is cut-off, formed round the arbor 112 and pushed into the magazine by the transfer blade 160, thus moving the leading piece in the magazine through an opening 126 in the plate 126. The pusher blade 122 then lifts the U-shaped piece so that its ends project above the plate 118, and through an already formed ring on a chain or finding, and the upper die descends to close the ends of the U and form a ring. The machine cycle is started by depressing a pedal and thereafter proceeds automatically until the cycle is complete, the end of one phase of movement initiating the next movement. The pneumatic circuit is described with reference to Fig. 6 (not shown). A spring may be fitted inside the cover-plate 116 to reduce the area of the slot 247, Fig. 4a (not shown).