GB1110683A - Improved spring coiling machine - Google Patents

Abstract

1,110,683. Coiling wire; shearing. TORRINGTON MANUFACTURING CO. 8 March 1966 [29 July, 1965], No. 10102/66. Headings B3E and B3W. A spring coiling machine comprises means for feeding wire to engage an arbor 36, and a coiling tool 38 which engages the wire to bend it into a coil of predetermined diameter whilst permitting the wire to be moved in a lateral direction by first and second pitch tools 40, 42 which bend the wire to introduce the desired pitch. In a first embodiment, Figs. 2 and 3, wire 20 is fed through a quill 32 to engage a projecting portion 100 of the arbor 36. The wire then engages a cylindrical coiling roller 112 which bends it upwards to coil about the arbor 36, contacting an adjustable recoil tool 44, which is clamped to the arbor, as it does so. When the coil is completed the wire feed stops and a knife 48 is swung downwards by rotation of an arm 256 which pushes down an arm 248 against the action of a spring 250 so that a knife element 242 co-operates with a shearing edge 46 on the recoil tool 44 to cut-off a length of coiled spring. The angular position of the arbor and hence of the tools 40, 42, can be adjusted by rotating it in a mounting 96. The diameter of the coil produced depends upon the position of the coiling tool 38 which can be adjusted. For the production of springs having diameters which vary from end to end the tool 38 may be moved in timed relation with the wire feed rolls by a cam operated link and lever mechanism, Fig. 4 (not shown). When springs of decreasing diameter are being wound the radius of the initial portion of the spring is increased by providing a " hump " on the cam of the link and lever mechanism, the tool then moving sharply towards the centre of the arbor and to increase the radius of the bent wire. Twisting of the wire as it is wound is controlled by antitwist means in the quill 32. As shown for winding wire of square cross-section the quill is provided with a square bore. The quill may be rotated about its axis to control the degree of twist and may be rotated in timed relation to the wire. When the pitch of the spring has to vary throughout its length the pitch tool 42 can be moved in timed relation to the wire feed rolls by a cam operated link and lever mechanism. In another embodiment, Figs. 7 and 9, wire 20a of circular cross-section is advanced by feed rolls 266, 268 through pre-cast units 270, 272 which introduce a slight bend into, or remove it from, the wire before it is passed through pairs of grooved anti-twist rolls 276, 278 to an arbor 282 about which it is coiled by contact with a coiling tool 286. At the point 284 where the wire contacts the arbor a V-shaped groove is provided thereon into which the wire is pressed by a grooved roller 288 to further resist twisting of the wire at a point close to the pitch tools 290, 294. The coiling and pitch tools may be arranged closer to the point at which the wire engages the arbor. Figs. 11, 12 (not shown).