JP6350309B2 - Manufacturing method of flat wire and manufacturing method of stator for rotating electrical machine - Google Patents

Description

  The present invention relates to a method for manufacturing a flat wire from a round wire material, and a method for manufacturing a stator for a rotating electrical machine using the flat wire.

  In a rotating electrical machine such as an electric motor or a generator, a coil disposed in a slot of a stator is formed from a rectangular wire having a rectangular cross section or a flat cross section. Since a flat wire is more expensive than a round wire, it is known to form a flat wire by rolling the round wire for the purpose of cost reduction. For example, in the flat wire coil manufacturing apparatus and the flat wire coil manufacturing method of Patent Document 1, it is described that a round wire is crushed by a flat forming roll to form a rectangular wire having a rectangular cross section. Further, it describes that a rectangular wire is wound around a winding mold to form a rectangular coil.

  Further, when joining the rectangular wires, the insulating coating layer at the ends of the rectangular wires is peeled off, and the exposed portions of the conductor layers exposed by the peeling are overlapped and joined. For example, in the film peeling method and the film peeling apparatus for a flat wire with a film disclosed in Patent Document 2, it is described that the film at the end of the flat wire with a film is peeled by a processing means.

JP 2000-82628 A JP 2014-60860 A

  However, when joining the flat wires, when the flat wires are overlapped with each other, a step between the exposed surface of the conductor layer and the surface of the insulating coating layer of the flat wire causes a difference between the surfaces of the exposed portions. There is a gap between them. Therefore, it is necessary to sandwich and deform the exposed portions of the conductor layer so as to eliminate the gap, and to bring the exposed portions of the conductor layer into contact with each other. Further, in order to sandwich the exposed portions of the conductor layer, it is necessary to make the exposed portions longer than necessary. This problem also occurs in Patent Document 2 and the like.

  The present invention has been made in view of such a background, and a method of manufacturing a rectangular wire and a stator for a rotating electrical machine that can facilitate joining of conductor layers in a conductor exposed portion and can shorten the conductor exposed portion. It was obtained in an attempt to provide a manufacturing method.

One aspect of the present invention is to peel off the coating layer at a predetermined position in a circular wire material having a circular cross section made of a conductive conductor layer and an insulating coating layer formed on the surface of the conductor layer, A peeling step for forming a conductor exposed portion;
Forming the conductor exposed portion, and the conductor covering portion and the boundary portion other than the conductor exposed portion to obtain a rectangular wire having at least a pair of flat portions in the round wire material. In the manufacturing method of the flat wire.

Another aspect of the present invention is a method for manufacturing a stator for a rotating electrical machine using a rectangular wire manufactured by the method for manufacturing a rectangular wire,
A coil forming step of forming a coil from the flat wire;
An arrangement step of arranging the plurality of coils in slots of the stator core;
A method of manufacturing a stator for a rotating electrical machine, comprising: a joining step of superposing and joining the conductor exposed portion in the flat wire and the conductor exposed portion in another flat wire.

In the manufacturing method of the said flat wire, joining of the conductor exposed parts which peeled the film layer is simplified by performing a peeling process before performing a shaping | molding process.
In the peeling step, the coating layer at a predetermined position in the round wire material is peeled to form a conductor exposed portion. At this time, a step is formed between the surface of the conductor layer in the conductor exposed portion and the surface of the coating layer in the conductor covered portion at the boundary portion between the conductor exposed portion and the conductor covered portion. In addition, the conductor exposed portion can be formed at any position between the intermediate position and the end position of the round wire material. By performing the peeling process on the round wire material, the configuration of the apparatus for peeling the coating layer can be greatly simplified.

Next, in the forming step, the conductor exposed portion, the conductor covering portion, and the boundary portion, which are the entire round wire material, are formed to obtain a rectangular wire having at least a pair of flat portions. At this time, in the process in which the round wire material is formed into a flat wire, the conductor exposed portion and the conductor covering portion are continuously formed via the boundary portion, and the surface of the conductor layer in the conductor exposed portion and the conductor covering portion (round The level difference between the surface of the coating layer in the wire material) is reduced. Therefore, when joining the flat wires, the conductor layers in the conductor exposed portion can be overlapped with each other without substantially deforming the conductor exposed portion.
Therefore, according to the above method for producing a rectangular wire, the conductor layers in the conductor exposed portion of the rectangular wire can be easily joined, and the conductor exposed portion can be shortened.

  In addition, a flat wire means the line of the cross-sectional shape which has at least a pair of plane part located in the mutually opposite side. In addition, the flat wire includes not only a rectangular cross section but also a flat cross section. The rectangular cross section includes not only a rectangular cross section but also a square cross section.

  In the method for manufacturing a stator for a rotating electrical machine, by using a rectangular wire manufactured by performing the peeling step and the forming step, the conductor layers can be easily joined to each other at the conductor exposed portion of the rectangular wire in the joining step. The exposed conductor can be shortened.

Explanatory drawing which shows the state which performs a peeling process to a round wire raw material concerning an Example, and forms a conductor exposed part. Explanatory drawing which shows the round wire raw material in which the conductor exposed part was formed concerning an Example. Explanatory drawing which shows the state which performs a rolling process to a round wire raw material concerning an Example, and shape | molds a rectangular wire with a rectangular cross section. Explanatory drawing which shows the cross section of the flat wire shape | molded from the round wire raw material by the rolling process concerning an Example. Explanatory drawing which shows the state which performs the expansion | extension process to a flat wire concerning an Example, and shape | molds in the required cross-sectional area. Explanatory drawing which shows the cross section of the rectangular wire by which the cross-sectional area was reduced by the expansion | extension process concerning an Example. Explanatory drawing which shows the flat wire in which the conductor exposed part concerning Example was formed. Explanatory drawing which shows the state which performs a rolling process to a round wire raw material concerning an Example, and shape | molds the flat wire of a cross-sectional flat shape. Explanatory drawing which shows the coil formed from the flat wire concerning an Example. Explanatory drawing which shows the state which joins the conductor layers in the conductor exposed part of a flat wire concerning an Example.

A preferred embodiment of the above-described flat wire manufacturing method will be described.
In the forming step of the method for manufacturing the flat wire, the round wire material having the conductor exposed portion, the conductor covering portion, and the boundary portion is passed between a pair of rolls that rotate opposite to each other, and is flattened in cross section. You may roll to the said rectangular wire of a shape.
In this case, when rolling, a circular wire material having a circular cross section having a conductor exposed portion, a conductor coating portion, and a boundary portion is passed between a pair of rolls that rotate opposite to each other. And a flat wire is formed in the cross-sectional flat shape by a pair of plane part located in the mutually opposite side, and a pair of circular arc part which connects a pair of plane part. In addition, the compression force by a pair of roll and the tensile force by the means to pull the round wire material can be applied to the round wire material.

Further, in the forming step, the conductor exposed portion, the conductor covering portion, and the round wire material having the boundary portion are orthogonal to the pair of first rolls and the pair of first rolls. And you may roll between the pair of 2nd rolls which rotate facing each other, and you may roll to the said rectangular wire of a cross-sectional rectangular shape.
In this case, when rolling, a circular wire material having a circular cross section having a conductor exposed portion, a conductor covering portion, and a boundary portion is passed between the pair of first rolls and the pair of second rolls. The rectangular wire is formed in a rectangular cross-section with a pair of first plane portions positioned on opposite sides and a pair of second plane portions orthogonal to the pair of first plane portions. In addition, the compression force by a pair of 1st roll and a pair of 2nd roll, and the tensile force by the means to pull a round wire material can be made to act on a round wire raw material.

Further, in the forming step, the round wire material after rolling in the rectangular wire is a flat rectangular wire, by extending maintaining the aspect ratio of the flat rectangular wire, be formed into cross-sectional area in need Good.
In this case, by rolling and stretching the round wire material, the pressure applied to the coating layer can be reduced, and the required rectangular wire can be manufactured. Here, the aspect ratio refers to the ratio of the vertical length to the horizontal length in the cross-sectional shape of the rectangular wire.

  And rolling of a round wire raw material is performed to such an extent that the cross-sectional area of a flat wire is not made too small. The flat wire is then stretched while maintaining its aspect ratio. At this time, a tensile force by means for pulling the flat wire acts on the flat wire, and no compressive force acts on the flat wire. Thereby, it can be made difficult to produce deterioration in the coating layer. Then, the coating layer is stretched mainly in the longitudinal direction, and a flat wire is formed into a required cross-sectional area. At this time, although the thickness of the coating layer decreases, the reduction rate of the thickness of the coating layer due to elongation is smaller than the reduction rate of the thickness of the coating layer due to rolling. Thereby, the insulation fall in a rectangular wire can be suppressed small.

Moreover, in the said peeling process, the peeling tool or peeling apparatus made to oppose the outer peripheral surface of the said round wire raw material is used, and this peeling tool or this peeling apparatus and the said round wire raw material are made relative to the circumferential direction of this round wire raw material. And the coating layer at the predetermined position may be peeled off.
In this case, the coating layer on the entire circumference in the circumferential direction of the round wire material can be continuously peeled by the cutting tool. Therefore, the coating layer at a predetermined position can be quickly and accurately peeled at the target thickness.

Moreover, in the said peeling process, after setting the said predetermined position which forms the said conductor exposed part to the intermediate position and both ends position in the said round wire raw material, and after performing the said peeling process, before performing the said molding process Alternatively, after the forming step, the round wire material or the flat wire may be divided into two at the conductor exposed portion at the intermediate position.
In this case, the peeling process is simultaneously performed on a plurality of rectangular wires to be manufactured, and the peeling process can be shortened.

Below, the Example concerning the manufacturing method of a flat wire and the manufacturing method of the stator for rotary electric machines is described with reference to drawings.
In the manufacturing method of the flat wire 1 of this example, as shown in FIG. 1, as a peeling process, the coating layer 3 at a predetermined position in the round wire material 10 is peeled to form a conductor exposed portion 21. The round wire material 10 has a circular cross section, and includes a conductive conductor layer 2 and an insulating coating layer 3 formed on the surface 201 of the conductor layer 2. In the round wire material 10, a portion where the conductor exposed portion 21 is not formed is referred to as a conductor covering portion 22, and a boundary portion between the conductor exposed portion 21 and the conductor covering portion 22 is referred to as a boundary portion 23.
Next, as shown in FIGS. 3 to 6, as a forming step, the conductor exposed portion 21, the conductor covering portion 22, and the boundary portion 23 in the round wire material 2 are formed to obtain a rectangular wire 1 having a rectangular cross section.

First, the manufacturing method of the flat wire 1 of this example is explained in detail.
As shown in FIG. 9, the rectangular wire 1 of this example is used for the coil 4 arrange | positioned at the stator core 5 of the rotary electric machine used as an electric motor, a generator, a motor generator, etc. As shown in FIG. The flat wire 1 is formed in the shape of the coil 4 and is joined to another flat wire 1 formed in the shape of the coil 4 via the conductor layer 2 in the conductor exposed portion 21. The flat wire 1 has a rectangular cross-section formed by a pair of flat surface portions 11 located on opposite sides and a pair of side surface portions 12 that connect the pair of flat surface portions 11 to each other. The pair of flat portions 11 constitutes a pair of long sides in a rectangular cross section, and the pair of side portions 12 constitutes a pair of short sides in a rectangular cross section.

  As shown in FIGS. 1 and 2, in the peeling process of this example, a peeling tool 61 that is opposed to the outer peripheral surface of the round wire material 10 is used, and the peeling tool 61 and the round wire material 10 are By rotating relatively in the circumferential direction C, the coating layer 3 at the intermediate position 101 and the both end positions 102 as predetermined positions is peeled off. In the peeling process, a rotation support device 62 that supports the round wire material 10 and rotates the round wire material 10 around its central axis is used.

The peeling tool 61 of this example is a tool that contacts or partially cuts or grinds the coating layer 3 on the outer circumferential surface of the round wire material 10 in the circumferential direction C. Then, the entire circumference of the coating layer 3 at the intermediate position 101 of the round wire material 10 is obtained by rotating the round wire material 10 by the rotation support device 62 and bringing the peeling tool 61 into contact with the outer peripheral surface of the rotating round wire material 10. Peel continuously. Moreover, when performing this peeling, the peeling tool 61 can be slid to the longitudinal direction (axial direction) L of the round wire raw material 10, and the position of the longitudinal direction L which peels the coating layer 3 can be changed.
Instead of using the peeling tool 61, a peeling device that melts and removes the coating layer 3 can also be used. This peeling apparatus can be, for example, a laser processing apparatus that performs laser processing as non-contact processing.

In the forming process of this example, the flat wire 1 is formed from the round wire material 10 by performing a rolling process and an extending process. In the rolling step, as shown in FIG. 3, a pair of first rolls 71 that rotate a circular wire material 10 having a circular cross section having a conductor exposed portion 21, a conductor covering portion 22, and a boundary portion 23 to face each other, , Passing between a pair of second rolls 72 that are orthogonal to the pair of first rolls 71 and rotate opposite to each other. Then, as shown in FIG. 4, the round wire material 10 is rolled into a rectangular wire 1 having a rectangular cross section so that the conductor exposed portion 21, the conductor covering portion 22 and the boundary portion 23 have a desired aspect ratio.
At this time, a pair of flat surface portions 11 are formed by the pair of first rolls 71, and a pair of side surface portions 12 are formed by the pair of second rolls 72. Further, the pair of flat surface portions 11 and the pair of side surface portions 12 are formed by being compressed (squeezed) by the pair of first rolls 71 and the pair of second rolls 72.

In the rolling process, the round wire material 10 can also be rolled by passing the round wire material 10 twice or more between the pair of first rolls 71 and between the pair of second rolls 72. The round wire material 10 can be simultaneously passed between the pair of first rolls 71 and the pair of second rolls 72. Further, after the round wire material 10 is passed between the pair of first rolls 71 and formed into a flat wire, the flat wire is passed between the pair of second rolls 72 to form a rectangular cross section (a rectangular cross section). , A rectangular wire 1 having a square cross section).
Further, as shown in FIG. 8, by passing the round wire material 10 only between the pair of first rolls 71, the pair of side surface portions 12 have an arc shape in which the surface shape of the round wire material 10 remains. You can also. In this case, the flat wire 1 is formed in a flat cross-sectional shape.

As shown in FIGS. 4 and 6, the aspect ratios of the conductor exposed portion 21, the conductor covering portion 22, and the boundary portion 23 in the rectangular wire 1 rolled in the rolling process are in the range of 1: 1 to 1: 6. . The aspect ratio is represented by a ratio between the length of the flat surface portion 11 constituting the long side portion and the length of the side surface portion 12 constituting the short side portion in the rectangular cross section. Note that the aspect ratio of the conductor exposed portion 21 may be slightly different from the aspect ratio of the conductor covering portion 22 by the thickness of the coating layer 3, particularly when the side surface portion 12 is formed in an arc shape.
Further, in the extension step, as shown in FIGS. 5 and 6, the flat wire 1 is extended while maintaining the aspect ratio of the conductor covering portion 22, and the flat wire 1 is formed into a required cross-sectional area. In addition, in FIGS. 3-6, the rectangular wire 1 after performing a rolling process is shown with the code | symbol 1A.

In the peeling process of this example, as shown in FIG. 2, the coating layer 3 at the intermediate position 101 and both end positions 102 in the round wire material 10 is peeled to form a plurality of exposed conductor portions 21. At this time, at the boundary portion 23 between the conductor exposed portion 21 and the conductor covering portion 22, the surface 201 of the conductor layer 2 in the plurality of conductor exposed portions 21 and the portion other than the conductor exposed portion 21 in the round wire material 10. A step 31 is formed between the surface 301 of the coating layer 3 of a certain conductor covering portion 22. Further, after the peeling process is performed, the round wire material 10 is divided into two at the conductor exposed portion 21 at the intermediate position 101. And the two round wire raw material 10 in which the conductor exposed part 21 was formed in the both ends is formed.
In this example, the coating layer 3 on the entire circumference in the circumferential direction C of the round wire material 10 can be peeled off by the peeling tool 61 while rotating the round wire material 10 around its central axis. Therefore, the configuration of the apparatus for peeling the coating layer 3 can be greatly simplified.

  In the rolling process, as shown in FIG. 3, the pulling means 73 pulls the tip 103 of the round wire material 10, and the round wire material 10 is moved between a pair of rotating first roll 71 and second roll 72. The round wire 10 is passed in the longitudinal direction L. At this time, the compression force by the pair of first rolls 71 and the pair of second rolls 72 and the tensile force by the tension means 73 act on the round wire material 10. The rolling of the round wire material 10 is performed until the conductor covering portion 22 has a rectangular cross section with a desired aspect ratio, and is performed so as not to make the cross sectional area of the flat wire 1 too small. In this example, based on the cross-sectional area of the round wire material 10 before rolling, the round wire material 10 is rolled within a range where the reduction rate of the cross-sectional area of the round wire material 10 is 6% or less.

  Next, in the extension step, as shown in FIG. 5, the tip 103 of the flat wire 1 is pulled by the tension means 73, and the flat wire 1 is extended while maintaining its aspect ratio. At this time, a tensile force by the tension means 73 acts on the flat wire 1 and no compressive force acts. As a result, the coating layer 3 can be made difficult to deteriorate. And the coating layer 3 is extended mainly in the longitudinal direction L, and the flat wire 1 is shape | molded by the required cross-sectional area. In this example, the rectangular wire 1 is extended within a range in which the reduction rate of the sectional area of the rectangular wire 1 is 12% or less with reference to the sectional area of the round wire material 10 before rolling.

Moreover, although the thickness of the coating layer 3 decreases in the stretching process, the decreasing rate of the thickness of the coating layer 3 in the stretching process is smaller than the decreasing rate of the thickness of the coating layer 3 in the rolling process. Thereby, the insulation fall in the flat wire 1 can be suppressed small.
Further, when the flat wire 1 is processed to form the coil 4, even if processing stress such as bending or stretching is applied to the flat wire 1 and the coating layer 3 deteriorates, it is necessary for the coil 4 (the coating layer 3). It is possible to ensure a good insulation performance.

  Moreover, in the rolling process and the elongation process, the entire round wire material 10 on which the conductor exposed portions 21 are formed as described above is formed into a rectangular wire 1 having a rectangular cross section. At this time, as shown in FIGS. 5 and 7, in the process of forming the round wire 10 into the flat wire 1 and the process of extending the flat wire 1, the conductor exposed portion 21 and the conductor covering portion 22 form the boundary portion 23. The step 31 between the surface 201 of the conductor layer 2 in the conductor exposed portion 21 and the surface 301 of the coating layer 3 in the conductor covering portion 22 becomes small.

  Thus, the taper portion 32 formed in the coating layer 3 at the boundary portion 23 between the conductor exposed portion 21 and the conductor covering portion 22 is stretched through the rolling process and the stretching process to form a gently tapered surface. Further, depending on the rolling method in the rolling process and the stretching process in the stretching process, it is considered that the surface 201 of the conductor layer 2 in the conductor exposed portion 21 and the surface 301 of the coating layer 3 in the conductor coating portion 22 are substantially flush with each other. . In this case, it is considered that the taper portion 32 in the coating layer 3 at the boundary portion 23 is almost eliminated.

Next, the manufacturing method of the stator for rotary electric machines of this example is explained in detail.
In the method for manufacturing a stator for a rotating electrical machine, a stator is manufactured using a flat wire 1 manufactured through a peeling process and a molding process.
First, in the coil forming step, as shown in FIG. 9, the coil 4 is formed by bending the rectangular wire 1 on which the conductor exposed portion 21 is formed. At this time, the flat wire 1 can be formed into a necessary shape by the mold after being wound around the winding frame and formed in a spiral shape. The flat wire 1 is formed into the coil 4 in a state where the pair of flat portions 11 are directed in the radial direction of the stator core 5. Further, the flat wire 1 also forms a connecting wire 41 for connecting the coils 4 to each other.

Next, in the arranging step, the plurality of coils 4 are arranged in the slots 51 of the stator core 5. Each coil 4 can be arranged on the stator core 5 in a distributed winding state.
Next, in the joining step, as shown in FIG. 10, the end of the flat wire 1 constituting the coil 4 and the end of the flat wire 1 constituting the connecting wire 41 are overlapped. At this time, almost no step is formed between the surface 201 of the conductor layer 2 in the conductor exposed portion 21 and the surface 301 of the coating layer 3 in the conductor covering portion 22, whereby the conductor layer 2 in the conductor exposed portion 21 is not formed. Almost no gap is formed between the surfaces 201. Thereby, the conductor layers 2 in the conductor exposed portion 21 can be brought into contact with each other without substantially deforming the conductor exposed portion 21. And the conductor layer 2 in the conductor exposed part 21 can be joined by pressurizing the superimposed conductor exposed part 21 with the pressurizing tool 81 and welding or soldering.

  Therefore, according to the manufacturing method of the rectangular wire 1 and the manufacturing method of the stator for a rotating electrical machine of this example, the joining of the conductor layers 2 in the conductor exposed portion 21 of the rectangular wire 1 can be facilitated. Moreover, the conductor exposed part 21 can be shortened, and the external shape of the coil end part (the part of the coil 4 protruding from the end surface of the stator core 5) of the stator for a rotating electrical machine manufactured using the flat wire 1 can also be reduced. .

DESCRIPTION OF SYMBOLS 1 Flat wire 10 Round wire material 2 Conductor layer 21 Conductor exposed part 22 Conductor coating | cover part 23 Boundary part 3 Coating layer 4 Coil 61 Stripping tool 71 1st roll 72 2nd roll

Claims (7)

Peeling to form a conductor exposed portion by peeling off the coating layer at a predetermined position in a circular wire material having a circular cross section made of a conductive conductor layer and an insulating coating layer formed on the surface of the conductor layer Process,
Forming the conductor exposed portion, and the conductor covering portion and the boundary portion other than the conductor exposed portion to obtain a rectangular wire having at least a pair of flat portions in the round wire material. A method of manufacturing a flat wire.   In the forming step, the round wire material having the conductor exposed portion, the conductor covering portion, and the boundary portion is passed between a pair of rolls rotating opposite to each other, and rolled into the flat wire having a flat cross section. The manufacturing method of the flat wire of Claim 1 characterized by the above-mentioned.   In the molding step, the round wire material having the conductor exposed portion, the conductor covering portion, and the boundary portion is orthogonal to the pair of first rolls and the pair of first rolls. 2. The method for producing a rectangular wire according to claim 1, wherein the rectangular wire is rolled between the pair of second rolls rotating opposite to each other and rolled into the rectangular wire having a rectangular cross section. In the forming step, the round wire material after rolling in the rectangular wire has a feature in that the flat rectangular wire, by extending maintaining the aspect ratio of the flat rectangular wire is formed into a cross-sectional area in need The manufacturing method of the flat wire as described in any one of Claims 1-3.   In the peeling step, a peeling tool or peeling device that is opposed to the outer peripheral surface of the round wire material is used, and the peeling tool or the peeling device and the round wire material are relatively moved in the circumferential direction of the round wire material. The method for producing a rectangular wire according to any one of claims 1 to 4, wherein the coating layer is peeled off at a predetermined position by rotation. In the peeling step, the predetermined position for forming the conductor exposed portion is set to an intermediate position and both end positions in the round wire material,
After performing the peeling step and before performing the forming step or after performing the forming step, the round wire material or the flat wire is divided into two at the conductor exposed portion at the intermediate position. The manufacturing method of the flat wire as described in any one of Claims 1-5 characterized by the above-mentioned. A method for manufacturing a stator for a rotating electrical machine using a flat wire manufactured by the method for manufacturing a flat wire according to any one of claims 1 to 6,
A coil forming step of forming a coil from the flat wire;
An arrangement step of arranging the plurality of coils in slots of the stator core;
A method of manufacturing a stator for a rotating electrical machine, comprising: a joining step of superimposing and joining the conductor exposed portion in the rectangular wire and the conductor exposed portion in another rectangular wire.

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