GB817907A - A method and means for the feeding and cutting off of wires in spring-winding, wire-bending, wire-straightening and like machines - Google Patents

Abstract

817,907. Making springs; feeding and cutting; coiling. HACK, K. July 17, 1956, No. 22022/56. Classes 83 (2) and 83 (4). In a method for feeding and cutting off wire in spring winding, wire-bending, wire-straightening and like machines, the wire from a continuous stock is brought to the working tools under tension and whilst the worked portion of the wire is being cut off the unworked portion immediately behind it is held, this holding continuing until such unworked portion is engaged by the working tools. Apparatus for coiling a fine-wire spring comprises camoperated jaws 3 and 9, Figs. 5 and 6, carried on spring-loaded arms 4, 15 which are geared together and pivotally mounted on shafts 25, 26 rotatable in a slide 22. The arms 4, 15 are biased apart by a spring and are closed by an adjustable cam 33. The jaw 3 is adjustably fixed while the jaw 9 is slidably mounted in the arm 15 and urged by a spring, the clampng pressure being adjusted by a screw 16. While the jaws are open the tip of jaw 9 projects beyond a knife 12 mounted adjacent to it. The knife 12 is interchangeable and may be mounted on either jaw. A winding spindle 44 carries a mandrel 47 and may be raised or lowered by a two-part cam 49. During operation the jaws are closed to grip the wire stock 1 already tensioned by a previous spring-winding operation, the spring being thereby compressed, retracting the jaw 9 to expose the knife 12 which coacts with edge 19 of the jaw 3 to cut the wire during completion of the movement of the pivoted arms. Prior to cutting the wire but after gripping it the mandrel begins its ascent to free a previously-formed spring. After cutting the wire, further stock is drawn out to a position under the mandrel by actuating the slide 22. The spindle is then lowered, the wire being located between the mandrel and a carrier claw 46 and rotated to coil the wire to form a spring; during coiling the jaws open and return to their initial position. The base-plate 23 may be displaced by means of a knurled nut 41 to locate the run of the wire stock for winding right or left-hand springs. The invention may be applied to working thick wires, operation then being by electromagnetic or hydraulic means.