JP4481664B2 - Manufacturing method of flat insulated wire - Google Patents

Description

  The present invention relates to a method for producing a flat insulated wire used for an insulated coil, a flat insulated wire produced by the production method, and an insulated coil using the same.

  Conventionally, when wound in a coil shape, the cross-sectional shape has a higher space factor than a circular conducting wire (hereinafter referred to as a round wire), and the miniaturization of equipment and the like can be expected. In the following, a rectangular insulated conductor having an insulating layer provided on the outer periphery thereof has been used.

  As a manufacturing method of the flat wire used for this flat insulated wire, the prior art wire drawing (Patent Document 1), unidirectional rolling (Patent Document 2), slit processing (Patent Document 3), and combining them (For example, Patent Document 4) is applied to produce a rectangular wire. In recent years, it has been desired to improve the space factor by reducing the accuracy required for rectangular wires, in particular, the corner portion R (circled portions in FIG. 3, R1 to R4).

  However, the above-described method for manufacturing a rectangular wire has various problems that there is a limit to reducing the corner portion R and that a complicated manufacturing process has to be performed. First, in wire drawing, a tensile load always acts on the lead wire during processing, and the workpiece (conductor) is not sufficiently filled into the corner portion of the die, so there is a limit to reducing R at the corner portion. is there. Further, in order to reduce R at the corner portion, particularly in the case of a small diameter, a large number of dies are required, which increases the complexity of the process and the cost.

  In the rolling process in one direction, the side (52a) in contact with the rolling roll is processed flat, but the side (52b) not in contact with the rolling roll is as shown in FIG. There was a limit to what could be improved to some extent.

  In slit processing, the corner portion R is small and has an edge (the corner portion is almost perpendicular), but due to the occurrence of flash specific to slit processing, the flash inhibits the formation of the insulating layer at the stage of providing the subsequent insulating layer. There is a problem that a process for removing the flash is required, the process becomes complicated, and the effect of the flash removal is exerted even on the corner part without the flash, resulting in the corner part having R to some extent. .

  In other words, in the prior art, there is a limit to reducing the corner angle R of the conductor of the manufactured flat wire, and the process of removing the flash is necessary in the slit processing that can make the corner portion a right angle, and The process has a problem that R is given to a corner portion without burrs.

JP 2002-260461 A Japanese Patent No. 3151895 JP 2001-291444 A JP 2002-307104 A

  An object of the present invention is to solve the above-described problems. Specifically, the corner R of the flat part of the flat wire after cold working is small, and a process such as flash removal is provided. It is an object of the present invention to provide a method of manufacturing a rectangular insulated conductor having a manufacturing process of no rectangular wire.

The above issues
(1) A copper wire having a circular cross-section is passed through the gap of a cassette roller die having a gap having a substantially square cross section formed by two pairs of rolling rolls facing each other, and is cold-worked by the rolling roll. A rectangular insulated lead wire comprising: a processing step of processing a copper wire having a flat cross-sectional shape; and a forming step of forming an insulating layer by electrodeposition on the outer periphery of the copper wire having a flat cross-sectional shape. Manufacturing method,
(2) After the said process process, the manufacturing method of the flat insulated lead wire as described in (1) which has a wire drawing process process by the die | dye which has a square-shaped hole further,
(3) The method for producing a rectangular insulated lead wire according to (1) or (2), wherein the ratio of the short side to the long side of the copper wire having a flat cross-sectional shape is 1: 1 to 1: 2.
(4) The method for producing a flat insulated wire according to (1) to (3), wherein the insulating layer is made of an acrylic water-dispersed resin varnish
(5) A flat insulated wire produced by the method for producing a flat insulated wire according to any one of (1) to (4),
(6) The problem can be solved by an insulating coil formed by winding the rectangular insulated conductor wire according to (5).

  According to the present invention, since the corner portion R is smaller than the rectangular wire produced by the manufacturing method as in the prior art and no flash is generated, an insulating layer is formed on the outer periphery of the produced rectangular wire. Even if formed, a sufficient and uniform insulating film (insulating layer) can be formed in the corner portion, and an insulating coil having a large space factor can be manufactured.

The manufacturing method of the flat insulated conductor of this invention is demonstrated using FIG. A bus bar (round wire having a circular cross section) 2 is pulled out from the delivery bobbin 1, and is cold-rolled through the bus bar 2 to a cassette roller die (hereinafter referred to as CRD) 4 having two opposing rolling rollers via a guide roll 3. Process. Thereafter, the bus bar (flat wire 5) processed into a rectangular cross section by the CRD 4 is wound around the winding bobbin 8 via the guide roll 6 and the cabstan 7. Subsequently, the rectangular wire 5 is drawn out from the winding bobbin 8 and cleaned (cleaning tank 9), and then the rectangular insulated conductor 13 is wound around the product winding bobbin 12 through the electrodeposition tank 10 and the baking tank 11. A cross section of the flat insulated conductor 13 is shown in FIG.
Alternatively, although not shown in the drawing, the process 1 (the process of forming the bus bar into a flat wire) and the process 2 (the process of forming an insulating layer on the outer periphery of the flat wire) are continuously manufactured without being wound around the winding bobbin. Wind a flat insulated conductor around the winding bobbin.

  A known material is applied to the bus 2 applied to the present invention. For example, Cu, Cu alloy, Al, Al alloy, Ag, Ag alloy are applied. More specifically, for example, 6N-Cu (Cu having a purity of 99.9999% or more used for audio-related equipment). ), 7N-Cu (Cu with a purity of 99.99999% or more), and the like. When processing extremely expensive and soft (easy to break) materials (buses) such as high purity 6N-Cu and 7N-Cu into flat wires, tension is not applied at the time of processing, unnecessary material costs, Processing by CRD, which will be described later, is optimal in that processing costs (flash removal performed after slit processing) are not required. In addition, the bus selected from these materials may be applied with a combination of wire drawing and at least one annealing step to adjust strength and elongation.

  The guide rolls 3 and 6 are provided before and after the CRD 4 to be described later, and the center of the busbar 2 before rolling, the center of the cross-sectional shape where the CRD 4 is formed are the same axis, and the center of the rectangular wire 5 after rolling This is for stable positioning on the line.

As shown in FIG. 2, the CRD 4 used in the present invention has a gap A formed by two pairs of opposing rolling rollers (41, 42 and 43, 44). Here, the bus 2 passes through the gap A from the back surface to the front surface of the paper, and is cold-worked from a round wire to a flat wire.
Here, the gap A indicates an area calculated by the distance between 41c in FIG. 2 and 42c in FIG. 2: distance e) × (distance between 43a in FIG. 2 and 44a in FIG. 2: distance f). The formation of the air gap A includes a distance a between the rolling roller 41 and the rolling roller 43 (a distance between 41a and 43a in FIG. 2) and a distance b between the rolling roller 42 and the rolling roller 43 (between 42a and 43a in FIG. 2). Distance), distance c between the rolling roller 41 and the rolling roller 44 (distance between 41b and 44a in FIG. 2), distance d between the rolling roller 42 and the rolling roller 44 (distance between 42b and 44a in FIG. 2), rolling It is determined by the distance e between the roller 41 and the rolling roller 42 (the distance between 41c and 42c in FIG. 2). The distance a, the distance b, the distance c, and the distance d are preferably 0 mm to 0.3 mm in order to reduce the angle R of the corner portion of the obtained rectangular wire. When the length on the short side of the flat wire after rolling is 0.5 mm or less, it is more preferably 0 mm to 0.1 mm. In order to make the corner R of the corner most small, 0.005 mm to 0.05 mm is most preferable.
Here, the length on the short side of the rectangular wire indicates the length Y in FIG. Moreover, when the cross-sectional shape of the rectangular wire is a square, measurement may be performed using either X or Y.
The distance e may be determined as appropriate depending on the desired width (thickness) of the flat wire 5.

The outer diameter of the rolling rolls 41, 42, 43, 44 may be appropriately set depending on the wire diameter of the bus 2 to be processed and the size of the flat wire after processing, specifically, an outer diameter of 5 mm to 200 mm. Are preferred. The distance e between the rolling rolls 41 and 42 and the distance f between the rolling rolls 43 and 44 are preferably 0.1 mm to 10 mm, although depending on the size of the cross-sectional area of the round wire and the flat wire before and after processing. In particular, when processing a rectangular wire having a small cross-sectional area, 0.1 mm to 0.5 mm is preferable. Further, the relationship between e and f is preferably e: f = 1: 1 to 1: 2, and the obtained rectangular wire has a true square (square) cross section, and the space factor is best. Most preferred is 1-1: 1.2. Examples of the material of the rolling roll include ceramic, cemented carbide, tool steel, and high-speed tool steel, but tool steel is preferable from the viewpoint of economy.
Each rolling roll may be a drive type or a non-drive type, but a non-drive type is preferable in that the equipment is inexpensive.

Further, the relationship between the cross-sectional area of the bus bar 2 before processing: B and the cross-sectional area of the rectangular wire 5 after processing: S (calculated by X × Y in FIG. 3) is calculated by the equation (1),
(Processing rate (W (%) = 100 × (B−S) / B) (1) Formula If W is 5% ≦ W ≦ 15%, R at the corner of the flat wire 5 is It is preferable because a dimension equivalent to the corner R of the corner portion of the flat wire produced by performing the flash removal process after the slit processing of 0.05 mm to 0.07 mm can be obtained.

  The capstan 7 is used to adjust the drawing force of the flat wire 5 wound around the take-up bobbin 8 and the centrifugal force generated in the take-up bobbin 8 at the time of winding. When handling a thin wire of 0.5 mm or less on the short side, it is necessary to prevent disconnection. A known device may be applied to the capstan 7. Generally, the flat wire 5 may be wound around the capstan 7 two to three times and then wound around the winding bobbin 8. Is not wound up, and may proceed to the electrodeposition process described later. In addition, a step (skin pass step) is provided between the guide roll 6 and the capstan 7 to provide a wire drawing die (not shown) having a square die hole and to adjust the cross-sectional shape of the wire processed by the CRD 4. Also good. The skin pass process may be performed within a range in which the processing rate (%) before and after the skin pass process is 5% to 20%, and the processing rate may be calculated in the same manner as the equation (1).

  Subsequently, the electrodeposition process will be described. In the electrodeposition process, the flat wire 5 wound around the take-up bobbin 8 (or the flat wire drawn directly from the capstan 7 without being wound around the take-up bobbin) is immersed in the cleaning tank 9, and the surface of the flat wire Remove foreign substances, oxides, etc. adhering to the surface. A known method may be applied as the cleaning means, and for example, ultrasonic cleaning, plasma irradiation, pickling, or a combination of these may be applied. By washing, the surface property of the flat wire 5 is improved, and the adhesion with the insulating layer by electrodeposition is improved.

In the electrodeposition tank 10 of the present invention, the insulating layer 14 is provided on the outer periphery of the flat wire 5 by electrodeposition. In general, means for providing an insulating layer on the outer periphery of the conducting wire include dipping method, electrodeposition method and the like. However, for a rectangular wire having a corner portion (particularly a rectangular wire having a small corner portion angle R), a corner is provided. An electrodeposition method that is excellent in forming an insulating film on the part is preferred. As the electrodeposition material (electrodeposition varnish), a known material may be applied. Specifically, the relation of the insulating film thickness of the corner portions (R1 to R4) ≧ the insulating film thickness of the flat portion (51a). In view of the above, an application of an acrylic water-dispersed resin varnish is preferred, and an epoxy-acrylic water-dispersed resin varnish is particularly preferred from the viewpoint of excellent heat resistance. The electrodeposition conditions using this electrodeposition varnish may be, for example, the conditions described in Japanese Patent Publication No. 07-120491.
The thickness of the insulating layer to be formed is 1 μm to 5 μm, more preferably 1.5 μm to 3 μm at the flat portion (51a).

  The baking tank 11 of the present invention is provided to remove excess solvent and the like in order to use an insulating film formed by electrodeposition as an insulating layer. For example, when the above-described modified acrylic resin varnish is applied, the atmosphere temperature in the baking tank 11 is preferably 100 ° C to 700 ° C, more preferably 200 ° C to 450 ° C. If the temperature is lower than 100 ° C., sufficient adhesion cannot be obtained, and if it exceeds 450 ° C., the formed insulating layer is thermally deteriorated and the desired withstand voltage characteristic is not exhibited, or the product life tends to be shortened. .

  Further, in the method for producing a flat insulated wire of the present invention, a cleaning tank (not shown) for removing excess electrodeposition varnish may be appropriately provided between the electrodeposition tank 10 and the baking tank 11. After baking, the flat insulated wire 13 may be wound around the product winding bobbin 12. However, for products in which a coating layer is further formed on the outer periphery of the insulating layer, each tank (not shown) for forming the coating layer is illustrated. Z)) may be set as appropriate.

  The produced flat insulated wire 13 is cut to a desired length and then wound to be used as an insulation coil. Examples of the type of winding include aligned winding, edgewise coil winding, α winding, and the like, and may be appropriately matched to the mode to be used. For example, the winding is applied to a voice coil, a motor coil, an inductor coil, and the like. In particular, when applied to a voice coil, it is preferable to apply 6N—Cu or 7N—Cu in terms of obtaining a sound with less noise.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these descriptions.

A flat wire was produced under the conditions shown in Table 1, and then an insulating layer was formed on the outer periphery of the flat wire by electrodeposition. The process for forming the insulating layer (electrodeposition process) was the same as in the examples and comparative examples. Moreover, the copper wire was used for the bus-bar.
Example 1: CRD gap A (0.43 mm × 0.43 mm (distance between rolling rollers 41 and 42 is 0.43 mm, between rolling rollers 43 and 44), with a bus having a wire diameter of 0.494 mm through a guide roll The distance is 0.43 mm)), and a flat wire is produced through a guide roll and a capstan, and then an insulating layer is formed on the outer periphery of the flat wire by the following electrodeposition process. A flat rectangular insulated conductor was produced.
Example 2: A rectangular insulated conductor was produced in the same manner as in Example 1 except that the wire diameter of the busbar was 0.506 mm.
Example 3 A rectangular insulated conductor was produced in the same manner as in Example 1 except that the diameter of the busbar was 0.510 mm.
Example 4 A CRD gap A (0.45 mm × 0.45 mm (the distance between the rolling rollers 41 and 42 is 0.45 mm, between the rolling rollers 43 and 44) through a guide roll through a bus having a wire diameter of 0.510 mm Cold-worked through a distance of 0.45 mm)), skin-passed (□ passed through a wire drawing die with a 0.43 mm die hole formed: processing rate: 8.69%), guide roll, cap A flat wire was prepared through a stun, and an insulating layer was formed under the same conditions as in Example 1 to produce a flat insulated conductor.
Comparative Example 1: A rectangular insulated conductor was formed in the same manner as in Example 1 except that a bus bar having a wire diameter of 0.550 mm was passed through a wire drawing die having a □ 0.43 mm die hole and subjected to cold working (wire drawing). Produced.
Comparative Example 2: After cutting 0.44 mm in width from a plate material having a thickness of 0.44 mm (slit processing) and then performing a burr removing step, a rectangular insulated conductor was produced in the same manner as in Example 1.

(Electrodeposition process)
Cleaning tank: Organic solvent, ultrasonic cleaning electrodeposition tank: Epoxy-acrylic water-dispersed resin varnish (varnish temperature: 25 ° C)
Baking tank: 400 ℃ for 10 minutes in air

(Measure corner angle R)
The x, y, X, and Y shown in FIG. 3 were measured using a microscope (magnification: 100 times), and the corner R and the cross-sectional area of the produced rectangular wire were calculated by the following equations.
Angle R (mm) = (x + y) / 2
In Table 1, the average of the four corner portions is shown as the corner corner angle R produced.
Flat wire cross-sectional area S (mm) = X × Y
Table 1 shows the processing rate calculated using the cross-sectional area S of the rectangular wire.
Processing rate W (%)
= 100 x (cross-sectional area of busbar-cross-sectional area of rectangular wire)) / (cross-sectional area of busbar)

  According to the present invention, the rectangular insulated lead wire produced in the rectangular wire manufacturing process having a small R at the corner portion of the flat wire used for the flat insulated conductor and having no process such as flash removal has an increased space factor. It can be used as an excellent insulating coil.

It is a figure which shows an example of the manufacturing method of the flat insulated wire of this invention. It is a figure which shows the structure of CRD used for this invention. It is a figure which shows a corner | angular part and its R (R1-R4) measurement location in the cross section of a flat wire. It is a figure which shows an example of the cross section of the flat insulated wire produced with the manufacturing method of the flat insulated wire of this invention. It is a figure which shows the cross-sectional shape of the flat wire produced with the conventional unidirectional rolling roll.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Feeding bobbin 2 Bus bar 3, 6 Guide roll 4 Cassette roller dice 41, 42, 43, 44 which has 2 sets of opposing rolling rollers 5 Rolling roller 5 Flat wire 51 Flat wire cross section 52 It was produced by rolling in one direction. Flat section 7 Cabstan 8 Winding bobbin 9 Cleaning tank 10 Electrodeposition tank 11 Baking tank 12 Product winding bobbin 13 Rectangular insulated conductor 131 Conductor 132 Insulating layer A Cavity Z Near the gap R1, R2, R3, R4 Corner part x, y of the rectangular wire Measurement point X, Y for determining the R of the corner part Measurement point for determining the cross-sectional area of the rectangular wire

Claims (6)

A copper wire having a circular cross section is passed through the gap of a cassette roller die having a substantially square gap in cross section formed by two pairs of rolling rolls facing each other, and the cross section is formed by cold working with the rolling roll. A method for producing a rectangular insulated conductor, comprising: a step of processing into a copper wire having a rectangular shape, and a forming step of forming an insulating layer by electrodeposition on the outer periphery of the copper wire having a flat cross-sectional shape. .   The manufacturing method of the flat insulated wire of Claim 1 which has a wire drawing process by the die | dye which has a square-shaped hole after the said process further. The method for producing a rectangular insulated conductor according to claim 1 or 2, wherein a ratio of a short side to a long side of the copper wire having a flat cross-sectional shape is 1: 1 to 1: 2.   The method for producing a rectangular insulated conductor according to claim 1, wherein the insulating layer is made of an acrylic water-dispersed resin varnish.   A flat insulated wire produced by the method for producing a flat insulated wire according to claim 1. An insulating coil formed by winding the flat insulated wire according to claim 5.

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