GB2070084A

GB2070084A - Method and Apparatus for Winding Wire on to Cores and Wire Bobbins Resulting Therefrom

Info

Publication number: GB2070084A
Application number: GB8104355A
Authority: GB
Original assignee: Tinsley Wire Sheffield Ltd; Tinsley Wire Ltd
Current assignee: Tinsley Wire Sheffield Ltd; Tinsley Wire Ltd
Priority date: 1980-02-23
Filing date: 1981-02-12
Publication date: 1981-09-03
Also published as: LU83155A1; FR2476620A1; DE3106417A1; BE887634A

Abstract

A method of winding wire (8) on a core (4), achieving great density without welding together of turns during subsequent annealling, comprises traversing the wire along the rotating core at a rate such that adjacent turns in any one traverse are spaced from each other, controlling the tension, and altering the traverse progressively to taper off the cross- section of the wound wire mass towards each end of the core, which may be a plain cylindrical tube (4) with one flange (15), or the core may have a cylindrical tubular portion and a frusto-conical portion diverging therefrom. Apparatus comprises a traversed guide (7) for feeding the wire close to the wound wire, the belt- driven traverse being reversed by stops on an intermittently rotated screwed shaft cooperating with reversing limit switches on respective ends of a traverse carriage. Jack 20 pivots the core to the vertical for doffing. <IMAGE>

Description

SPECIFICATION Method and Apparatus for Winding Wire on to Cores and Wire Bobbins Resulting Therefrom This invention relates to a method of winding wire on to a core and apparatus for carrying out the method and wire bobbins resulting therefrom.

It is known to wind wire on to a core in order to achieve a greater density of wire compared with a loose wire coil, but the wire has to be wound either on to a core with end flanges which are removed after the wound wire has been bound by straps extending between the wire and the core and with ends of the straps secured outside the wire, or on to a core with permanent end flanges between which the wire is traverse wound or with one permanent end flange on which the core stands upright and upon which wire is coiled from the bottom and, later, unwound from the top.In either case, compaction of the turns of wire against the flange or flanges is such that any subsequent heat treatment of the wound wire (i.e., before unwinding), for example for annealling, often results in welding together of a considerable number of turns, such that unwinding becomes impossible or difficult or, at least, wastefui of wire as well as wasteful of time and labour is removing damaged wire and making good a continuous wire feed.

The primary object of the invention is to provide a method of winding wire on to a core by which the above disadvantages are overcome.

A secondary object of the invention is to provide apparatus for carrying out the method of the invention.

Yet another object of the invention is to provide wire bobbins wound by means of the method of the invention and facilitating use of the apparatus of the invention.

According to one aspect of the present invention, a method of winding wire on to a core comprises anchoring one end of the wire to the core, rotating the core, traversing the wire along the rotating core at such a rate that adjacent turns in any one traverse are spaced from each other, controlling the tension of the wire being wound, and altering the traverse progressively so that the wire mass of the wound bobbin occupies three zones comprising a central zone having a constant cross-sectional area, and two end zones each of which has a cross-sectional area diminishing progressively from that of the central zone down to zero.

Consequently, the turns of wire in any one traverse do not lie substantially parallel to the turns of wire in adjacent traverses, and the pressure between crossing wires in adjacent traverses is not allowed to be such that any subsequent heat treatment of the wound wire can result in welding together of any significant number of turns even close to the core.

The core may comprise a cylindrical tube, which may be provided with a flange (or plate) at one end only, the progressive altering of the traverse being effected by reducing the extent of traverse progressively from both ends of the core, whereby the central zone has a cylindrical outer envelope and the end zones each have a frustoconical outer envelope, and the rate of reduction of the extent of traverse is preferably equal from both ends, so that-in combination with the tension of the wire-the firmness of the haunching at the ends of the wound wire (i.e., the frusto-conical end zones) is sufficient to avoid collapsing of the end turns of wire upon the core being turned to the vertical with etiher end lowermost, but with a flange (or plate) at one end only of the core the wound bobbin will usually be stood on the flange.

Alternatively, the core may comprise a tube having a cylindrical portion one end of which is integral with the smaller end of a frusto-conical portion, the extent of traverse being slightly less than the length of the cylindrical portion of the core, and the progressive altering of the traverse being effected by shifting it progressively from the cylindrical portion towards the larger end of the frusto-conical portion, whereby one end zone has a frusto-conical outer envelope and a cylindrical inner envelope contiguous with the cylindrical inner envelope of the central zone, while the other end zone has a frusto-conical inner envelope and a cylindrical outer envelope contiguous with the cylindrical outer envelope of the central zone.The wound bobbin is readily adapted to stand on the larger end of the frusto-conical portion of the core, or for that end to stack on the other end of the core of another similar bobbin.

The core is preferably rotated about a horizontal axis during winding, even though during subsequent unwinding of the wire the core may be mounted vertically with one frusto-conical end zone or the outwardly frusto-conical end zone uppermost, to facilitate upward withdrawal of the wire from all round the bobbin.

Rotation of the core is preferably controlled so that the wire is wound at constant linear speed, thus facilitating the setting of a constant tension, but the rotation and the tension are preferably independently adjustable, to suit a wide range of wire sizes; but it is contemplated that the maximum wire size to be wound by this method will be about 1.00 mm diameter.

The rate of traverse is preferably adjustable, so that the pitch of the turns in any one traverse can be adjusted in accordance with wire size. The method of the invention is considered to be suitable for any wire size up to 1.00 mm diameter. The minimum pitch-considered suitable is 4 inch (6 mm) for wires of less than 1.00 mm diameter, and the maximum pitch considered feasible is 3 inches (76 mm).A specific example used was 141 inches (32 mm) pitch for 0.46 mm diameter wire wound on a plain cylindrical core having a length of 22 inches (550 mm) and a diameter of 5 inches (127 mm), which with a reduction in traverse length of 0.001 inch (0.025 mm) per traverse and a tension of 3 to 4 kg at 1 600 feet/minute (447 metres/minute) resulted in 80-90 kg of wound wire with firm haunching having a half angle of 30 . For wire of 0.37 mm diameter the reduction in traverse length would be 0.001 inch (0.025 mm) every 12 traverses, while for wire of 0.62 mm diameter the reduction in traverse length would be 0.0015 inch (0.038 mm) per traverse.

According to another aspect of the present invention, apparatus for winding wire on to a core comprises a frame on which is rotatably mounted a shaft with an adaptor for drivingly engaging acore, powered drive means for rotating the shaft, guide means for feeding wire close to the wound wire on the core and for traversing the wire along the core, restraining means for tensioning the wire being wound on the core, and control means for altering the traverse of the guide means progressively.

The shaft is preferably rotatable by the drive means when the core is in a horizontal position, but the shaft preferably has dis-engageable bearing means for one end of the core and horizontally pivoted bearing means is provided for the other end of the core, to enable the core to be brought to an upright position for loading and unloading. The pivoted bearing means is preferably provided with a lever arm and doubleacting piston-and-cylidner, to facilitate swinging of the core between its horizontal and upright positions. The core may however be rotatable in a vertical position, and when additional means to bring it to that position for loading and unloading would not be necessary.

The guide means if preferably mounted on a carriage movable along a slide parallel to the shaft when being rotated by the powered drive means, and the control means for progressively altering the traverse of the guide means preferably consists of a pair of limit switches mounted adjacent to the respective ends of the carriage and contactable by respective stops mounted on a screwed shaft (which may have right and left handed screws with one stop on each screw) extending parallel to the carriage slide, the screw shaft being rotatable slowly and/or intermittently in dependence on the wire feed speed or-the speed of rotation of the core shaft or the speed of traverse, so as to alter the traverse progressively at both ends of the core. The drive for the traversing means may be geared down from the powered drive means, or it may be independent therefrom.

The restraining means for tensioning the wire being wound may be of any known kind, e.g., a capstan with spinner and brush, and/or multiple staggered rollers, and is preferably readily adjustable, e.g., by adjusting the extent of interference of the brush and/or by adjusting the gap between adjacent rollers, as the case may be.

Multiple staggered rollers are particularly advantageous in that they can also serve to straighten the wire.

According to yet another aspect of the present invention, a wire wound bobbin comprises a cylindrical tubular core with a flange or plate at one end only, the core having received wire wound thereon in accordance with the method of the invention. The end of the core remote from the flange is preferably provided with a notch for engagement by a projection on the adaptor on the power-driven shaft of the apparatus of the invention.

According to a further aspect of the present invention, a wire wound bobbin comprises a core having a cylindrical tubular portion one end of which is integral with the smaller end of a frustoconical portion, the core having received wire wound on both portions thereof in accordance with the method of the invention. The end of the cylindrical tubular portion remote from the frustoconical portion is preferably provided with a notch for engagement by a projection on the adaptor on the power-driven shaft of the apparatus of the invention.

The wound wire may be bright annealed, with annealing taking place on the core after winding, without any appreciable welding together of turns of the wire even close to the core. Indications are that, as compared with loose coils, bobbins wound in accordance with the invention can carry as much as five times the weight of wire, thus increasing the effective capacity of annealing chambers by as much as seventy-five per cent, and reducing wire wastage to as little as one per cent.

The various aspects of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a front view of a wire-winding machine forming part of apparatus in accordance with the invention with its guard raised and showing a core being loaded; Figure 2 is a view of the wire-winding machine from the front and the right-hand side showing the core at the start of winding, but with the guard still raised; Figure 3 is a fragmentary view showing part of Figure 2 to a larger scale; Figure 4 is a diagrammatic side elevation of the apparatus showing guide means for feeding wire to the core and restraining means for tensioning the wire being wound; Figure 5 is a fragmentary view showing traversing means for the guide means and control means for altering the extent of traverse of the guide means; ; Figure 6 is a part-sectional elevation of a wire wound bobbin as wound on the core and by the apparatus of Figures 1 to 5; and Figure 7 is a part-sectional elevation of another wound bobbin as wound on a different core but in the same apparatus with slight modifications to the wire-winding machine.

In Figures 1 to 5, a wire-winding machine comprises a frame 1 on which is rotatably mounted a shaft 2 with an adaptor 3 for drivingly engaging a core 4, a motor 5 and gearbox 6 within the frame for rotating the shaft (through appropriate drive connections which are not shown), guide means 7 for feeding wire 8 close to the wound wire on the core (but initially close to the core itself) and for traversing the wire along the core, and control means 9 for reducing the extent of traverse of the guide means 7 progressively from both ends of the core. The apparatus is completed by restraining means 10, 11 (Figure 4 only) for tensioning the wire 8 being wound on the core 4.

The shaft 2 is rotatable by the drive means 5, 6 when the core 4 is in horizontal position (see Figure 2), the adaptor 3 having a projection 12 for engagement with a notch 13 in one end 14 of the core (see also Figure 6), which is a cylindrical tube with a flange 1 5 at the other end 16. The core 4 is loaded and unloaded in upright position (see Figure 1), a bearing 17 for the flanged end t6 having a spigot (not visible) locating in the tube and also having a horizontal pivot 1 8 on which the bearing swings. A lever arm 19 and double acting piston-and-cylinder 20 facilitates swinging of the core between its horizontal and upright positions.A handwheel 21 (Figure 2 only) with a screw (not visible) acts through the bearing 1 7 to urge the notched end 14 of the core 4 into engagement with the adaptor 3 on the shaft 2. A grab 22 on a chain hoist block 23 engages holes 24 (see also Figure 6) in the notched end 14 of the core 4 for lifting and lowering of the core, but more especially for lifting and lowering of the wound bobbin 4W (Figure 6 only).

Before lowering a machine guard 25, to engage a catch 26 with a safety switch 27 to permit starting of the drive means 5, 6, the end of the wire 8 is led through the guide mean 7. This consists of an arm 28 projecting upwardly from a carriage 29 (Figure 5) through protective brushes 30, and the arm carries a pair of guide spindles 31 and a pivoted finger 32 with a ring guide 33 at its free end (see Figure 3). The core 4 is rotated by hand to wrap a few turns of wire 8 round the core to anchor the end of the wire, as shown in Figure 2.

When the wire 8 has been anchored on the core 4 and the guard 25 has been lowered into operative position with the catch 26 engaged with the safety switch 27, the drive means 5, 6 can be started so that the shaft 2 and core 4 are power driven, with the ring guide 33 close to the core. The carriage 29 carrying the guide means 7 is traversed by a gear-belt drive 34 (Figure 5) reversal of which is effected by a pair of limit switches 35A, 35B mounted adjacent respective ends of the carriage and contactable by respective stops 36A, 36B mounted one on each of right and left handed screws 37A, 378 respectively on a shaft 38 extending parallel to a slide 39 for the carriage, the double-screw shaft being rotatable intermittently in dependence on the speed of traverse, so as to reduce the extent of traverse progressively from both ends of the core.

The restraining means 10, 11 (Figure 4) for tensioning the wire 8 being wound consists of, on the one hand, a capstan 40 with spinner 41 and brush 42, and, on the other hand, of multiple staggered rollers 43A, 43B and the tension is readily adjustable, e.g., by adjusting the extent of interference of the brush 42 with the spinner 41 and/or by adjusting the gap between the adjacent rollers 43A, 43B. The wire feeding part of the apparatus also includes a freely rotatable pulley 44 driven by the wire 8 led over it, a tachogenerator 45 driven by the pulley 44 and controlling the speed of rotation of the shaft 2 and core 4, a capstan 46 driven to conform its peripheral speed to that of the wire 8, and a tension compensator 47 to absorb any slight fluctuations in speed and/or tension of the wire.

The progressive reduction of traverse of the guide means 7 from both ends of the core 4 results in the wire wound bobbin 4W (Figure 6) having a central zone C with a cylindrical outer envelope and two end zones E each having a frusto-conical outer envelope.

When the central zone C reaches such a diameter that wire being wound touches a "trip" bar 48 (Figure 1) the drive means 5, 6 is automatically stopped, and then the wound bobbin 4W can be removed from the machine by raising the guard 25, winding back the handwheel 21 to disengage the notch 1 3 in the core 4 from the projection 1 2 on the adaptor 3 of the shaft 2, actuating the piston-and-cylinder 20 to swing the bobbin upright, ready for lifting by means of the grab 22 on the chain hoist block 23. The trip bar 48 also seems to stop the machine in the event of breakage of the wire 8, the loose end on the core being flung out by centrifugal force into contact with the "trip" bar to cause a short circuit stopping power to the motor 5.

The alternative core 4' shown in Figure 7 consists of a tube having a cylindrical portion 49 one end of which is integral with the smaller end of a frusto-conical portion 50. The wire wound bobbin 4W' shown formed on the core 4' can be wound using the apparatus of Figures 1 to 5 with slight alterations to the machine.On the one hand, the bearing 1 7 will require a spigot appropriate to the inside of the frusto-conical portion 50 of the core 4', while, on the other hand, the shaft 38 will require replacing by a shaft having two screwed portions of the same hand, the stops 36A, 368 being set apart by slightly less than the length of the cylindrical portion 49 of the core 4', the traverse of the guide means 7 being shifted progressively (by simultaneous and equal movement of the stops 36A, 36B in the same direction along the screwed shaft) from along the cylindrical portion alone towards the larger end of the frusto-conical portion, so that the wound bobbin 4Wt has a central zone C with a cylindrical outer envelope, one end zone E with a frusto conical outer envelope, and one end zone E' with a cylindrical outer envelope. The core 4' has 8 notch 12 and two holes 24 in the end of the cylindrical portion 49 remote from the frusto conical portion 50 for the purposes previously specified with regard to the core 4 of Figures 1,2 and 6.

Claims

1. A method of winding wire on to a core comprising anchoring one end of the wire to the core, rotating the core, traversing the wire along the rotating core at such a rate that adjacent turns in any one traverse are spaced from each other, controlling the tension of the wire being wound, and altering the traverse progressively so that the wire mass of the wound bobbin occupies three zones comprising a central zone having a constant cross-sectional area, and two end zones each of which has a cross-sectional area diminishing progressively from that of the central zone down to zero.

2. A method as in Claim 1, wherein the core comprises a cylindrical tube, and wherein the progressive altering of the traverse is effected by reducing the extent of traverse progressively from both ends of the core, whereby the central zone has a cylindrical outer envelope and the end zones each have a frusto-conical outer envelope.

3. A method as in Claim 2, wherein the rate of reduction of the extent of traverse is equal from both ends.

4. A method as in Claim 1 , wherein the core comprises a tube having a cylindrical portion one end of which is integral with the smaller end of a frustoconical portion, wherein the extent of traverse is slightly less than the length of the cylindrical portion of the core, and wherein the progressive altering of the traverse is effected by shifting it progressively from the cylindrical portion towards the larger end of the frustoconical portion, whereby one end zone has a frusto-conical outer envelope and a cylindrical inner envelope contiguous with the cylindrical inner envelope of the central zone, while the other end zone has a frustoconical inner envelope and a cylindrical outer envelope contiguous with the cylindrical outer envelope of the central zone.

5. A method as in any one of the preceding Claims, wherein the core is rotated about a horizontal or vertical axis during the winding.

6. A method as in any one of the preceding Claims, wherein rotation of the core is controlled so that the wire is wound at constant linear speed and with constant tension.

7. A method as in Claim 6, wherein the rotation and the tension are independently adjustable, to suit a wide range of wire sizes.

8. A method as in any one of the preceding Claims, wherein the rate of traverse is adjustable so that the pitch of the turns in any one traverse can be adjusted in accordance with wire size.

9. Apparatus for winding wire on to a core comprising a frame on which is rotatably mounted a shaft with an adaptor for drivingly engaging a core, powered drive means for rotating the shaft, guide means for feeding wire close to the wound wire on the core and for traversing the wire along the core, restraining means for tensioning the wire being wound on the core, and control means for altering the traverse of the guide means progressively.

10. Apparatus as in Claim 9, wherein the shaft is rotatable by the drive means when the core is in a horizontal position.

11. Apparatus as in Claim 10, wherein the shaft has dis-engageable bearing means for one end of the core and horizontally pivoted bearing means is provided for the other end of the core, to enable the core to be brought to an upright position for loading and unloading.

12. Apparatus as in Claim 11, wherein the pivoted bearing means is provided with a lever arm and double-acting piston-and-cylinder, to facilitate swinging of the core between its horizontal and upright positions.

13. Apparatus as in any one of Claims 9 to 12, wherein the guide means is mounted on a carriage movable along a slide parallel to the shaft when being rotated by the powered drive means, and the control means for progressively altering the traverse of the guide means consists of a pair of limit switches mounted adjacent respective ends of the carriage and contactable by respective stops mounted on a screwed shaft extending parallel to the carriage slide, the screw shaft being rotatable slowly and/or intermittently in dependence on the wire feed speed or the speed of rotation of the core shaft or the speed of traverse, so as to alter the traverse progressively at both ends of the core.

14. Apparatus as in Claim 13, wherein the screwed shaft has right and left handed screws with one stop on each screw.

1 5. Apparatus as in any one of Claims 9 to 14, wherein the restraining means for tensioning the wire being wound consists of a capstan with spinner and brush, and multiple staggered rollers.

16. A wire wound bobbin comprising a cylindrical tubular core with a flange or plate at one end only, the core having received wire wound thereon in accordance with the method of Claim 2 or Claim 3.

17. A wire wound bobbin comprising a core having a cylindrical tubular portion one end of which is integral with the smaller end of a frustoconical portion, the core having received wire wound on both portions thereof in accordance with the method of Claim 4.

18. A wire wound bobbin as in Claim 1 6 or Claim 17, wherein the bobbin of wire is bright annealed.

19. A method of winding wire on to a core substantially as hereinbefore described with reference to the accompanying drawings.

20. Apparatus for winding wire on to a core substantially as hereinbefore described with reference to the accompanying drawings.

21. A wire wound bobbin substantially as hereinbefore described with reference to Figure 6 or Figure 7 of the accompanying drawings.