JP7767954B2 - Wire coil manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing a wire coil, in which a coil is produced by winding a metal wire such as a copper wire.

Coils made by winding metal wire such as copper wire include compact coils and loose coils. As described in Patent Document 1, compact coils are made by winding the wire around a winding jig with a tapered outer surface, pressing it axially with a coil compactor, and binding it with a metal band. Loose coils, on the other hand, are made by unwinding the wire from a coiler and winding it into a coil shape on a pallet. Multiple poles made of rod material are attached to the outer periphery of the pallet, and loose coils are placed within the area surrounded by the multiple poles so that their outer periphery comes into contact with multiple ports.

Japanese Patent Application Laid-Open No. 2004-114132

Compact coils are pressed axially, so they have a higher wire space factor than loose coils, but they require the installation of winding jigs and coil compactors, which inevitably increases coil manufacturing costs. Furthermore, a single compact coil is smaller than a loose coil, so it requires more frequent transport using a lift or similar device to load it onto a transport truck, etc., which inevitably increases transportation costs.

In contrast, loose coils do not require equipment such as coil compactors, but have the disadvantage of a low wire space factor. If the wire space factor of loose coils can be increased, the weight of coils that can be loaded onto a single pallet can be increased, making it possible to reduce the cost of transporting coils.

The present invention was devised in light of the above-mentioned problems, and aims to provide a loose coil that can increase the space factor of the wire and reduce the transportation costs of the coil.

One embodiment of a wire coil manufacturing method involves winding, onto a pallet, wire that is unwound in a spiral shape from a nozzle that rotates around a vertical central axis of rotation, to produce a loose coil. The method includes a base coil section forming process in which the wire is wound to form a cone-shaped base coil section on the top surface of the pallet, the top surface of which slopes downward toward the center of the pallet, and a stacked coil section forming process in which the wire is wound along the sloped top surface of the base coil section to form a stacked coil section above the base coil section, the top surface of which slopes downward toward the center.

The loose coil of the present invention has a base coil portion that is shaped like a mortar with a downwardly sloping upper surface, and a stacked coil portion that is formed by winding wire along the upper surface of the base coil portion. This increases the space factor of the wire, increases the weight of coils that can be loaded onto a single pallet, and reduces the cost of transporting the coils.

FIG. 10 is a front view showing the winding machine in a state in which the wire fed from the coiler is wound to form an inner coil portion. 1, (A) is a view taken along line AA in Fig. 1, showing the bottom surface of the coiler, and (B) is a view taken along line BB in Fig. 1, showing the plane of the inner coil portion. FIG. 10 is a front view showing the inner coil portion in a state where it has been dropped onto a pallet from the opening/closing shutter. 10 is a front view showing an initial coil section formed by assembling an outer coil section to the outside of an inner coil section and an outer coil section. FIG. FIG. 10 is a cross-sectional view of the coil showing the state in which the base coil portion is being formed on the initial coil portion. FIG. 10 is a partially cutaway front view showing a loose coil in a state in which a wire is wound on the upper side of a base coil portion to form a laminated coil portion. FIG. 7 is a plan view of the loose coil shown in FIG. 6.

<Coiler-type winding machine>
An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a front view of a coiler-type winding machine 10 (hereinafter simply referred to as the "winding machine 10"), also known as a coiler, which is used to produce loose coils of wire. The winding machine 10 is disposed above a conveyor 12, such as a roller conveyor, for transporting a pallet 11 serving as a loading platform. A copper or copper alloy wire rod W is supplied to the winding machine 10. The wire rod W is produced by supplying molten copper or copper alloy to a continuous casting machine and then rolling the wire rod ingot from the continuous casting machine using a rolling mill. The loose coil produced on the pallet 11 by the winding machine 10 is transported to a wire drawing process where the wire diameter is uniformed.

The pallet 11 is formed from a square frame or plate material, and has multiple rods, or poles 13, attached to its outer periphery at intervals in the circumferential direction. As shown in Figure 2(B), six poles 13 are attached to the pallet 11, and the imaginary lines drawn inside these poles 13 roughly correspond to the outer periphery of the loose coil.

The winding machine 10 has a rotating body 15 mounted on a support base 14, and the rotating body 15 is rotatably mounted on the support base 14 by a plurality of guide rollers 16 provided on the support base 14. To drive the rotating body 15, an electric motor 17 is attached to the support base 14, and a drive roller 18 pressed against the outer surface of the rotating body 15 is driven to rotate by the electric motor 17, and the rotating body 15 is driven to rotate by the drive roller 18.

A box 22 equipped with pinch rollers 21 is attached to the support base 14, and the wire W passing through the pinch rollers 21 is unwound downward from the tip of a nozzle 23 attached to the rotor 15. As shown in Figure 2(A), the tip of the nozzle 23 is located at a constant radius R from the central axis of rotation O of the rotor 15, and the length of the wire W unwound per unit time from the tip of the nozzle 23, i.e., the unwound speed V, is set to a constant value. The rotation speed S of the rotor 15 can be changed by an electric motor 17. Note that the guide rollers 16 and drive roller 18 are not shown in Figure 2(A).

As shown in Figure 1, an opening/closing shutter consisting of two opening/closing members 24, 24 is disposed below the winding machine 10. The two opening/closing members 24, 24 are movable toward and away from each other, and each opening/closing member 24, 24 is supported movably on a support base (not shown). Note that while Figures 1 to 6 illustrate an opening/closing shutter consisting of two opening/closing members 24, 24, this is not limited to this, and the opening/closing shutter may be composed of, for example, six opening/closing members.

<Initial coil portion forming process>
FIG. 1 shows a state in which the wire rod W is being wound to form the inner coil portion 31. The inner coil portion 31 is formed by unwinding the wire rod W onto the open-close members 24 at a constant speed from the nozzle 23, which rotates around the central axis of rotation O, while the open-close members 24 are closed. As shown in FIG. 1, the wire rod W is spirally wound on the open-close members 24 to form the inner coil portion 31. When the inner coil portion 31 is being formed, the pallet 11 on which a loose coil has already been produced is transported from below the open-close members 24 by the conveyor 12, and an empty pallet 11 (i.e., no wire rod W is wound on it) is transported below the open-close members 24, as shown in FIG. 1. In this way, the inner coil portion 31 can be formed even while the empty pallet 11 is moving, allowing for continuous production of loose coils.

In the inner coil portion forming process, the wire W is spirally wound from the radially inner side toward the radially outer side, and then spirally wound from the radially outer side toward the radially inner side so as to be stacked on top of the wound wire W. By repeating this process multiple times, the inner coil portion 31 is formed. Note that the winding direction when winding the wire W spirally may be either clockwise or counterclockwise.

As shown in Figure 2 (B), the outer diameter d2 of the inner coil portion 31 is smaller than the maximum outer diameter of the area of the pallet 11 surrounded by the six poles 13, and the inner coil portion 31 is formed inside the opening/closing members 24, 24 in a region corresponding to the radial center (hereinafter also referred to as the center) of the pallet 11. The inner coil portion 31 is annular, having an outer peripheral surface 31a and an inner peripheral surface 31b, and a hollow hole 30 is formed inside the inner peripheral surface 31b.

As shown in FIG. 3, by opening the opening/closing members 24, 24, the inner coil portion 31 is dropped toward the center of the pallet 11 and placed in the center on the pallet 11. Following this dropping process, as shown in FIG. 4, wire W is wound around the outside of the inner coil portion 31 to form the outer coil portion 32. This produces an initial coil portion 33 consisting of the inner coil portion 31 and the outer coil portion 32. When forming the outer coil portion 32, the wire W is wound spirally from the radially inner side to the radially outer side, and then wound spirally from the radially outer side to the radially inner side so that it is stacked on top of the wound wire W. By repeating this process multiple times, the outer coil portion 32 is formed, having a height equivalent to that of the inner coil portion 31.

In Figure 4, diameter d1 is the inner diameter of the hollow space of the inner coil portion 31, and diameter d2 is the outer diameter of the inner coil portion 31. The outer peripheral surface of the initial coil portion 33, i.e., the outer peripheral surface 32a of the outer coil portion 32, contacts the pole 13, preventing the initial coil portion 33 from collapsing. In Figure 4, all of the wire rods making up the outer peripheral portion of the initial coil portion 33 are shown aligned and in substantial contact with the pole 13, but some of the wire rods W may not contact the pole 13.

As shown in FIG. 4, the rotation speed S of the nozzle 23 when forming the outer coil portion 32 is set slower than the rotation speed S of the nozzle 23 when forming the inner coil portion 31 as shown in FIG. 1. In other words, the rotation speed of the nozzle 23 when forming the radially outer portion of the coil portion is set slower than the rotation speed of the nozzle 23 when forming the radially inner portion. When the rotation speed S of the wire W that is paid out at a constant payout speed V is slowed, the wire W is paid out radially outward more than when the rotation speed S is fast, and the outer coil portion 32 is formed. In this way, the winding diameter of the wire W is adjusted by the rotation speed S of the nozzle 23.

The rotation speed S of the nozzle 23 may be changed in stages according to the coil diameter, or may be changed continuously and steplessly.

<Base coil portion forming process>
5 shows the state after the base coil forming step of forming the base coil portion 41 on the initial coil portion 33 is completed. The base coil portion 41 is formed by winding the wire W in more layers in the outer periphery than in the center. As shown in FIG. 5, the base coil portion 41 has an outer periphery 41a extending vertically along the pole 13 and an upper surface 41b inclined downward at an angle θ from the outer periphery toward the inner periphery in the radial direction, forming a mortar shape. The inner periphery of the base coil portion 41 roughly corresponds to the inner periphery 31b of the inner coil portion 31.

Note that in Figure 5, only a portion of the wire W used to form the coil is shown as a circular cross section, with the other portions hatched and the wire W not shown.

<Laminated coil portion forming process>
By winding the wire W on the inclined upper surface 41b of the base coil portion 41 along the upper surface 41b, a laminated coil portion 42 is formed on the upper side of the base coil portion 41, as shown in Fig. 6. Fig. 6 shows the state when the winding of the laminated coil portion 42 is completed, i.e., when the laminated coil portion forming step is completed.

The outer peripheral surface 42a of the laminated coil portion 42 is substantially flush with the outer peripheral surface 41a of the base coil portion 41. The laminated coil portion 42 is formed by winding wire W radially, layer by layer, so that the wire W is stacked along the upper surface 41b. The laminated coil portion 42 is formed with multiple layers of wire W on the upper surface 41b of the base coil portion 41. In other words, the upper layer coils constituting the laminated coil portion 42 are formed on the upper surface 42b, which is inclined at an angle θ relative to the lower layer coils. Each coil piece constituting the laminated coil portion 42 is wound around the upper surface of the cone-shaped coil by the wire W of the lower coil piece. This prevents wire W falling onto the upper surface from bouncing outward in the radial direction, and the wire W of the laminated coil portion 42 penetrates the cone-shaped upper surface, increasing the space factor of the base coil portion 41 and the laminated coil portion 42. Furthermore, the cross-sectional shape of the laminated coil portion 42, i.e., the packaging, is improved, and packaging deformation is also suppressed.

Experiments conducted by the inventors have shown that a downward inclination angle θ between the upper surface 41b of the base coil portion 41 and the cone-shaped upper surface 42b of the laminated coil portion 42 in the range of 10° to 30° is preferable for suppressing jumping and shifting of the wire W when winding the laminated coil portion 42 and achieving an improved space factor.

Figure 6 shows the outer surface of the loose coil 43, which consists of the initial coil portion 33, the base coil portion 41, and the stacked coil portion 42, with the upper portion of the stacked coil portion 42 partially cut away and shown hatched.

In this way, even when forming the base coil portion 41 and the stacked coil portion 42, the rotation speed of the nozzle 23 when forming the radially outer portion of the coil portion is set to be continuously or stepwise slower than the rotation speed of the nozzle 23 when forming the radially inner portion.

When forming the laminated coil portion 42, the rotation speed of the nozzle 23 is changed depending on whether it is the lower layer laminated coil portion 42 or the upper layer laminated coil portion 42 in Figure 6. Because the upper layer laminated coil portion 42 is closer to the nozzle 23 than the lower layer laminated coil portion 42, the rotation speed of the nozzle 23 is set slower to spread the wire W radially more than the lower layer laminated coil portion 42. In other words, the rotation speed of the nozzle 23 when forming the upper layer laminated coil portion 42 is set slower than the rotation speed of the nozzle 23 when forming the lower layer laminated coil portion 42. The change in speed may be continuous or stepwise.

The upper surface of the loose coil 43 has an upper surface 42b that is inclined downward from the radially outer side to the radially inner side (or upward from the radially inner side to the radially outer side) corresponding to the upper surface 41b of the base coil portion 41 described above. In this way, by maintaining the upper surface of the loose coil 43, i.e., the upper surface 42b of the stacked coil portion 42, in a state inclined at a predetermined angle θ in the radial direction, it is possible to prevent the loose coil 43 from collapsing.

In other words, the manufactured loose coil 43 consists of wire material W wound up to a predetermined height, with the exposed wire material W arranged above it wound at a predetermined angle θ in the radial direction. In particular, if the predetermined angle θ is in the range of 10° to 30°, the wire material W can be prevented from bouncing or shifting during transport on a lift or transport truck, making it less likely for the load to collapse.

Once the production of the loose coil 43 is complete, the opening/closing members 24, 24 are closed as shown in Figure 6, and the wire W is cut. The wire W may be cut by an operator using a cutting jig, or it may be cut automatically. The pallet 11 with the loose coil 43 loaded on it is transported to the outside by the conveyor 12, and a new, empty pallet 11 is transported below the opening/closing members 24, 24 by the conveyor 12. During this transport/removal process, the wire W is wound on the closed opening/closing members 24, 24, and production of the next inner coil section 31 begins, continuously producing loose coils 43.

Figure 7 is a plan view of the loose coil 43 shown in Figure 6. The outer diameter D of the loose coil 43 corresponds to the outer diameter D of the initial coil portion 33, and the inner diameter of the hollow hole 30 corresponds to the inner diameter d1 of the inner coil portion 31. The wire W that forms the inner surface of the hollow hole 30 is not shown in Figures 5 and 6.

The loose coil 43 described above has an initial coil section 33, which is the lowest coil section, but it is also possible to have a loose coil 43 consisting of a base coil section 41 and a stacked coil section 42.

<Improvement of space factor>
The loose coil 43 has a base coil portion 41 and a stacked coil portion 42 wound on the upper side thereof, and the stacked coil portion 42 is stacked along an upper surface 41b of the base coil portion 41, which is inclined like a mortar, and the upper stacked coil portion is stacked on an upper surface 42b of the stacked coil portion 42, which is also inclined like a mortar. As a result, the coil pieces of the base coil portion 41 and the stacked coil portion 42 are combined with each other, and the space factor of the wire W is increased.

In conventional manufacturing methods, wire is wound spirally, forming horizontally layered coils that are then stacked on top of each other. In contrast, in the present invention, the stacked coil portion 42 is formed on a sloping, cone-shaped surface. This increases the weight of the loose coil 43, even when the coil pieces are combined to form a loose coil of the same height as a loose coil formed by conventional manufacturing methods. This therefore increases the load weight (= coil weight) of the loose coil 43 that can be placed on the pallet 11, thereby reducing the transportation costs of the loose coil 43.

Furthermore, when the space factor of the wire W in the loose coil 43, i.e., the wire space factor, is increased, the wire W that constitutes the coil portion does not shift or bounce during transportation, thereby reducing the occurrence of damage to the wire W due to friction. Furthermore, because the loose coil 43 has a good wire space factor, it is possible to reduce the occurrence of tangled wire W when the wire W is drawn out from the loose coil 43 in the subsequent wire drawing process.

The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the invention. For example, the upper surface 41b of the base coil portion 41 and the upper surface 42b of the stacked coil portion 42 are linear, but as long as the imaginary line connecting the outer periphery and inner periphery of each upper surface 41b, 42b is within the range of the inclination angle θ, each upper surface 41b, 42b may be concave or convex.

10...coiler-type winding machine, 11...pallet, 12...conveyor, 13...pole, 14...support base, 15...rotating body, 17...electric motor, 23...nozzle, 24...opening/closing member, 30...hollow hole, 31...inner coil portion, 32...outer coil portion, 33...initial coil portion, 41...base coil portion, 42...stacked coil portion, 43...loose coil.

Claims (5)

A method for manufacturing a wire coil, comprising winding a wire that is helically fed from a nozzle that rotates around a vertical rotation center axis onto a pallet to manufacture a loose coil, comprising:
The wire rod is a copper or copper alloy wire rod produced by rolling a wire rod ingot supplied from a continuous casting machine using a rolling mill,
an inner coil portion forming step of winding the wire rod on an opening/closing shutter arranged above the pallet to form an inner coil portion;
a dropping step of dropping the inner coil unit from the opening/closing shutter onto the pallet;
an initial coil portion forming step of forming an outer coil portion by winding the wire rod around the outer side of the inner coil portion dropped onto the pallet, thereby forming an initial coil portion consisting of the inner coil portion and the outer coil portion;
a base coil portion forming process in which the wire is wound around the initial coil portion to form a base coil portion having a cone shape on the upper surface of the pallet, the upper surface of which is inclined downward toward the center of the pallet;
a laminated coil portion forming step of winding the wire along the inclined upper surface of the base coil portion to form a laminated coil portion above the base coil portion, the upper surface of which is inclined downward toward the center portion,
In the inner coil portion forming process and the initial coil portion forming process, the wire material unwound from the nozzle at a constant speed is spirally wound from the radial inner side to the radial outer side so as to be stacked on top of the wound wire material, and this is repeated multiple times in this method for manufacturing a wire coil. 2. The method for manufacturing a wire coil according to claim 1,
a coil winding section for winding a wire rod coil material to a first end of the coil winding section, the first end of the coil winding section being inclined downward toward the center portion of the coil winding section; 3. The method for manufacturing a wire coil according to claim 1 or 2,
The wire is fed out from the nozzle at a constant speed;
a nozzle rotating speed when forming a radially outer portion of the base coil portion or the stacked coil portion is slower than a nozzle rotating speed when forming a radially inner portion of the base coil portion or the stacked coil portion, and the wire is fed out from the nozzle. The wire coil manufacturing method according to claim 3, wherein the nozzle rotation speed is changed stepwise or continuously depending on the diameter of the base coil portion or the stacked coil portion. 5. The method for manufacturing a wire coil according to claim 3 or 4,
a nozzle rotating speed when forming an upper side of the stacked coil portion being slower than a nozzle rotating speed when forming a lower side of the stacked coil portion, and the wire is fed out of the nozzle.