JP2000295822A - Coil conductor of rotating machine, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the coil conductor of a rotating machine consisting of a rectangular wire whose end has such a form that it is excellent in close adhesion with insulating material. SOLUTION: According to this method, one angle and two main faces catching it of a covered cable 3 are ground with one rotating stone by relatively shifting rotating stones 1 and 2 in the direction of drawing, in condition that the covered wire consisting of a rectangular wire with an angle of R in specified curvature and being covered with an electric-insulating resin film 4 is tensed in its drawing direction. That is, in this method, a rotating stone which has a polishing face in such form that it can polish one angle and two main faces catching it at a stroke is used. Next, the electric-insulating film can be peeled off favorably without leaving all around the covered wire, by polishing the electric-insulating film 4 at the remaining two angles by the rotating stones in the same shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil conductor for a rotating electric machine and a method for manufacturing the same.

[0002]

2. Description of the Related Art As shown in FIGS. 8 and 9, an electric insulating resin film 101 at an end portion of a conductor wire 100 is formed of a helical reamer type resin film on a stator coil or a rotor coil of a small rotating electric machine. It is common to use a round wire that can be easily peeled using the peeling machine 102.

[0003]

However, there is a problem that the round wire has a smaller slot occupation ratio than the rectangular wire, and the output of the rotating electric machine cannot be improved. When the above-mentioned helical reamer type resin film peeling machine is used for peeling the electrical insulating resin film of the rectangular wire, it is not easy to control the relative movement of the helical reamer to the outer periphery of the rectangular wire, and it is difficult to guarantee sufficient film peeling quality Met.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the above problems, and has been made in consideration of the above problem. An object of the present invention is to provide a method of manufacturing a coil conductor of a rotating electrical machine having high yield and high productivity by realizing a film peeling method. The ends of the rectangular wire from which the electrically insulating resin film has been peeled off are connected to other conductor wires, especially rectangular wires, by arc welding, soldering, etc., and then insulated with an insulating resin such as liquid or powder epoxy resin. Is done.

Another object of the present invention is to improve the fluidity and adhesion at the end of the rectangular wire of the insulating resin.

[0006]

According to a first aspect of the present invention, there is provided a method of manufacturing a coil conductor for a rotating electrical machine, wherein a corner portion is formed of a flat rectangular wire having an R having a predetermined curvature. By rotating the grindstone relatively in the direction of extension in a state where the wire covered with the insulating resin film is pulled in the direction of its extension, one corner of the covered wire and the two main surfaces sandwiching it are brought together. Grind with two rotating whetstones. That is, in the present method, a rotary grindstone having a ground surface having a shape capable of simultaneously grinding one corner and two main surfaces sandwiching the corner is used.

[0007] By grinding each corner portion sequentially or simultaneously with the rotating grindstone, the electrically insulating resin film can be satisfactorily peeled over the entire circumference of the covered wire without any remaining peeling. More specifically, the present inventors first performed an experiment in which a rotary grindstone having a cylindrical surface-shaped grinding surface was relatively moved in the direction of extension to grind four planes of a flat wire one by one or two opposite planes. However, in this case, it has been found that the flat rectangular wire has a problem that an unpeeled portion occurs at the corner since the corner has an R.

Of course, if the conventional helical reamer is relatively moved while controlling the position in the direction surrounding the covering wire, the electrically insulating resin film should be completely peeled off. However, for this purpose, the coated wire must be completely fixed during peeling, and the helical reamer type position control must be perfectly performed. And high-speed processing was not easy.

Therefore, in this method, attention is paid to the fact that the flat wire has a flat main surface in the direction of extension, and the main surface is easily moved by relatively moving the ground surface along the flat main surface. This is based on the fact that the above electrically insulating resin film can be removed. Further, in this case, the grinding surface of the rotary grindstone is formed into a shape capable of grinding the corner portion and the two main surfaces sandwiching the corner portion at a time, while the grinding surface cannot grind a corner having a flat wire R. By grinding each corner sequentially or simultaneously on two opposing surfaces, it is devised that complete peeling can be performed over the entire circumference.

According to this stripping method, as compared with a conventional helical reamer type resin film stripping machine, complicated operation control of relatively rotating the rotating grindstone around the flat wire is not required, and furthermore, there is no need for a long time. The effect of changing the peeling length in the linear direction is much easier than that of a helical reamer type resin film peeling machine. The rotating grindstone may be any one having a large number of high hardness grinding protrusions on its surface, and is usually a material in which abrasive grains are filled in a base material portion. May be a file-like structure made of the same material.

According to a second aspect of the present invention, in the method for manufacturing the coil conductor of the rotary electric machine according to the first aspect, the grinding surface of the rotary grindstone further includes a cylindrical surface portion extending in the axial direction, a disk surface portion extending in the radial direction, and a cylindrical surface portion. And a conical surface portion having a diameter increasing from the cylindrical surface portion toward the disk surface portion between the disk surface portions. Further, the main surface on the wide side of the rectangular wire is ground at the cylindrical surface, and the main surface on the narrow side of the covered wire is ground at the disk surface.

With this arrangement, it is possible to equalize the relative speed of each portion of the cylindrical surface portion with respect to the wide-side main surface of the flat wire which has the largest wear load due to polishing because of its large area, and the wear of each portion of the cylindrical surface portion is reduced. At the same speed, deformation of the cylindrical surface can be prevented, and there is an advantage that wear of the cylindrical surface can be adjusted by adjusting the rotating grindstone in the radial direction.

Also, there is an advantage that a large number of linear marks can be easily formed in the axial direction on the wide-side main surface of the flat wire. The linear marks are effective for improving the flowability of the insulating resin described above. According to the method of claim 3, claim 1 or 2
Further in the method for manufacturing a coil conductor of the rotating electric machine described,
A pair of rotary grindstones each having a grinding surface capable of the two-side grinding described above are arranged diagonally across the coated wire, and four main surfaces and two corners of the coated wire are simultaneously ground.

With this configuration, since the rectangular wire is sandwiched between the two grindstones, it is possible to prevent the rectangular wire from elastically or plastically deforming from the grindstone by biasing one of the grindstones. The other rotating grindstone can prevent it, and can accurately grind the electrically insulating resin film.
According to the method of claim 4, in the method of manufacturing a coil conductor for a rotating electric machine according to claim 3, two corner portions remaining after grinding the four main surfaces and the two corner portions with the pair of rotary grinding wheels. Another grinding wheel is arranged diagonally across the coated wire for grinding. In addition, these other pair of rotary grindstones are arranged behind the first pair of rotary grindstones in the direction of extension of the wire. With this configuration, the predetermined area of the covered wire can be moved by a simple moving operation of relatively moving the two pairs of rotating grindstones once in the extending direction (the covered wire may be moved in the extending direction). The resin can be completely removed.

According to a fifth aspect of the present invention, in the method for manufacturing a coil conductor for a rotary electric machine according to any one of the first to fourth aspects, further, after the predetermined area of the covered wire is separated, the predetermined area is cut. This predetermined area of the covered wire is defined as the tip of the coil conductor. By doing so, it is possible to manufacture the coil conductor of the rotating electric machine having the resin exfoliation tip with high productivity.

According to a sixth aspect of the present invention, in the method for manufacturing a coil conductor of a rotating electric machine according to any one of the first to fifth aspects, the rotating grindstone further includes a conductor wire when the electrically insulating resin film is ground. Has a surface roughness and a rotational speed that form a large number of linear traces on its exposed surface in its longitudinal direction. In this way, a large number of linear marks can be formed at the tip of the coil conductor without adding a process. As described above, these linear marks are effective in improving the flowability of the above-described insulating resin after joining the ends of the rectangular wire.

According to a seventh aspect of the present invention, in the method for manufacturing a coil conductor for a rotating electric machine according to any one of the first to fifth aspects, the rotating grindstone further includes a conductor wire when the electrically insulating resin film is ground. Has a surface roughness and a rotation speed that form a satin-like fine uneven portion on the exposed surface of the substrate. If you do this,
A large number of satin-like fine unevenness portions can be formed at the tip of the coil conductor without adding a process. As described above, these fine irregularities are formed by bringing the main surfaces of a pair of rectangular wires into close contact with each other and joining them with a melt-type bonding material (solder or brazing material). This has the effect of improving the adhesion to the wire.

[0018] The coil conductor of the rotating electric machine according to claim 8 is:
The surface of the tip exposed by peeling off the electrically insulating resin film is
It is characterized by having a large number of linear marks extending in the longitudinal direction. With this configuration, as described above, the flowability of the insulating resin described above can be improved by the linear marks.
The coil conductor of the rotating electric machine according to claim 9 is characterized in that the surface of the tip end exposed by peeling off the electrically insulating resin film has a matte-shaped fine uneven portion.

According to this configuration, when the main surfaces of the pair of rectangular wires are brought into close contact with each other and are joined with a fusion joining material (solder or brazing material), the adhesion between the melt of the fusion joining material and the rectangular wire is improved. This has the effect of improving the performance. More specifically, the melt is less likely to drop or move from the surface of the rectangular wire due to its own weight or the like, and the joining reliability is improved. In addition, the adhesion of the fusion bonding material to the surface of the flat wire is, for example, to lower the flat wire end after lowering the flat wire end into a bath filled with the melt of the fusion bonding material. Can be done by operation.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the following examples.

[0021]

Embodiment 1 The principle of a method for manufacturing a coil conductor of a rotating electric machine according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 is a perspective view showing a state in which the four main surfaces and the two corners of a rectangular wire are ground by a pair of rotary grinding wheels, FIG. 2 is a schematic sectional view of FIG. 1, and FIG. 3 is ground by a pair of rotary grinding wheels of FIG. FIG. 4 is a schematic sectional view showing a step of removing the remaining electrically insulating resin film with another pair of rotating grindstones.

(Basic configuration) Reference numerals 1 and 2 denote rotating grindstones rotatably supported by a base (not shown) and rotated by a motor (not shown), and reference numeral 3 denotes a flat wire (covered wire) used as a stator coil of an alternator. An electrical insulating resin film 4 is applied to the surface of the rectangular wire 3. A pair of rotating whetstones 1,
Numerals 2 are arranged diagonally across the rectangular wire 3 and rotate at a predetermined rotation speed. Grinding surface of rotating grindstones 1 and 2 (flat wire 3
The surface which comes into contact with the cylindrical surface portion 5 extends in the axial direction, the disk surface portion 6 extends in the radial direction, and a cone having a diameter increasing from the cylindrical surface portion 5 toward the disk surface portion 6 between the cylindrical surface portion 5 and the disk surface portion 6. And a surface portion 7.

In FIG. 1, the flat wire 3 is a pair of upper and lower wide-side main surfaces 31, 32, and a pair of left and right narrow-side main surfaces 33, 34 provided at right angles to the wide-side main surfaces 31, 32; It has four corners 35 to 38 (see FIG. 3) formed between the main surfaces. In FIG. 1, cylindrical surface portions 5 of the rotary grinding wheels 1 and 2,
The width between 5 is set slightly smaller than the thickness of the flat wire 3,
The width between the disk surfaces 6, 6 is set to be slightly narrower than the width of the flat wire 3, and the width between the cone-shaped surfaces 7, 7 slightly bites into the corners 35, 36 (see FIG. 3) of the flat wire 3. Is set to The curvature of the cone-shaped surface portion 7 is set substantially equal to that of the corner portions 35 to 38.

(Step 1) In FIG. 1, when the flat wire 3 is moved to the near side, the corners 37,
The electrically insulating resin film 4 on the surface of the flat wire 3 excluding 38 is ground to expose the core of the flat wire 3. The cutting may be performed while pressing the ground surfaces of the rotary grindstones 1 and 2 against the surface of the flat wire 3 with a predetermined force by a spring (not shown).

As a result of this cutting, as shown in FIG. 3, film residues 41 and 42 remain at the corners 37 and 38. This requires clearance between the tip of the cylindrical surface portion 5 of the rotary grindstone 1 and the disk surface portion 6 of the rotary grindstone 2 and between the distal end of the cylindrical surface portion 5 of the rotary grindstone 2 and the disk surface portion 6 of the rotary grindstone 1. That's why. (Step 2) Next, the tip of the flat wire 3 is inserted between the other pair of rotating grindstones 8 and 9 shown in FIG.

The rotating grindstones 8 and 9 have the same shape as the rotating grindstones 1 and 2 described above and differ only in arrangement. The conical surface portions 7 of the rotating grindstones 8 and 9 grind the remaining film portions 41 and 42. As a result, the electrically insulating resin film 4 at the end of the flat wire 3 is completely removed by a length equal to the feed amount of the flat wire 3 in the extending direction. Further, in this embodiment, a number of fine irregularities are provided on the surface to be ground of the flat wire 3 by grinding while adjusting the roughness and the number of revolutions of the grinding surfaces of the rotary whetstones 1 and 2. This makes it easier for the melt of the solder or brazing material to be held on the surface of the flat wire 3 to be ground, so that the reliability of joining the end of the flat wire 3 to the other members by the fusion bonding material is improved. Is improved.

In this embodiment, the rotating grindstones 1 and 2 are adjusted in the axial direction thereof in accordance with the wear of the cylindrical surface portions 5 of the rotating grindstones 1 and 2 due to the wear of the respective grinding surfaces of the rotating grindstones 1 and 2. In addition, the distance between the two axes can be adjusted to be shorter due to wear of the disk surface portions 6 of the rotating grindstones 1 and 2, and the rotating grindstones 1 and 2 can be used longer. (Modification 1) In the above embodiment, the electric insulating resin film 4 around the entire circumference of the flat wire 3 was peeled off by using two pairs of diagonally arranged rotating grindstones, but only the rotating grindstones 1 and 2 were used. After step 1,
These may be displaced with respect to the flat wire 3 to remove the remaining film portion 41 with the rotating grindstone 1 and remove the remaining film portion 42 with the rotating grindstone 2. Alternatively, the rotating grindstones 1 and 2 may be rotated only, and after the step 1, the flat portions 3 may be inserted into the rotating grindstones 1 and 2 from opposite directions to cut the remaining film portions 41 and 42.

Alternatively, the rotating grindstone 1 and the rotating grindstone 2 may be separately provided, the rotating grindstone 3 and the rotating grindstone 4 may be separately provided, and the corners 35 to 38 of the flat wire 3 may be sequentially cut. (Modification 2) A modification will be described with reference to FIG. In this embodiment, the cylindrical surface portion 5 of each of the grinding wheels 1, 2, 8, and 9 is used.
A plurality of peaks 51 and valleys 52 are provided coaxially at a predetermined pitch in the axial direction.

In this manner, the main surface 31 of the flat wire 3
32, multiple linear marks 3A can be formed in the axial direction (extending direction). Therefore, after joining the ends of the flat wire 3, the flowability of the insulating resin which is applied to the end by the linear mark and becomes liquid from the beginning or later can be improved. In this embodiment, a large number of peaks 51 and valleys 52 are provided coaxially on the cylindrical surface 5 in the axial direction. However, the same effect can be obtained by rotating a slightly coarse grinding wheel at high speed. it is obvious.

(Modification 2) A modification will be described with reference to FIG. In this embodiment, the angles of the cylindrical surface portion 5a, the disk surface portion 6a, and the cone-shaped surface portion 7a of each of the rotary grindstones 1, 2, 8, and 9 with respect to the axis of the rotary grindstones 1a and 2a are changed. Can achieve the same effect.

In this embodiment, according to the wear of the grinding wheel,
The convenience arises that the distance between the centers of the two grinding wheels only needs to be adjusted. In addition, uneven wear of each part of the grinding surface of the rotary grindstone can be corrected using a correction grindstone for correcting the wear. (Modification 3) In the above embodiment, the flat wire 3
7 was cut and removed.
As shown in (1), when cutting a rectangular wire 3 having a required length from a long rectangular wire, it is also possible to automatically perform resin cutting of a region where resin is to be peeled off using two pairs of rotating grindstones.

The apparatus shown in FIG. 7 will be described in more detail.
Reference numeral 100 denotes a rectangular wire coil material drum on which the rectangular wire 3 is wound. After the flat wire 3 drawn from the drum 100 is slackened by the roller 102 of the slack portion 101,
The paper is fed to the leading end of the wire at a predetermined speed by a pair of feed rollers (not shown) of the feed unit 103.

Reference numeral 104 denotes a distortion removing section provided with a number of distortion removing rollers 105. The flat wire 3 from which the distortion has been removed is sent to the first stripping section 106, and the electrical insulation property of the area where the resin is to be peeled off. The resin film 4 is firstly removed by the rotating grindstones 1 and 2 shown in FIG.
Except for 1 and 42. Subsequently, the electrically insulating resin film 4 in the area of the rectangular wire 3 where the resin is to be peeled is sent to the second strip 107, and the rotary grindstone 8 shown in FIG. 9 removes the remaining film portions 41 and 42. Subsequently, the flat wire 3 is sent to the cutting unit 108 and cut into a predetermined length.

In this embodiment, in order to prevent the electrically insulating resin film 4 in the area of the rectangular wire 3 where the resin should not be peeled off from being removed by the rotating grindstones 1, 2, 8 and 9, Perform the operation. When the starting end of the area where the resin is to be peeled reaches the position where the rectangular wire 3 comes into contact with the rotary grindstones 1 and 2 of the first peeling portion 106, the feeding of the rectangular wire 3 is stopped and the rotary grindstones 1 and 2 are brought into contact with the rectangular wire 3 Then, the rotating grindstones 1 and 2 are moved in the axial direction or in the direction toward the axis of the counterpart rotating grindstone so as to approach the rectangular wire 3 so that the grinding surface is in close contact with this area, and then the feed of the rectangular wire 3 is performed. Is resumed to remove the area where the rotating grindstones 1 and 2 are to be stripped of resin, leaving the film remaining portions 41 and 42, and then the end of the rectangular wire 3 where the resin is to be stripped is the rotation of the first stripping section 106. When reaching the position away from the grindstones 1 and 2, the feeding of the flat wire 3 is stopped, and the rotating grindstones 1 and 2 are moved in the direction of the rotating grindstones 1 and 2 in the axial direction or in the direction toward the axis of the partner rotating grindstone. To move it away from the flat wire 3 and then restart the feed of the flat wire 3. Repeating the step of. As a result, the resin can be removed from the predetermined area of the rectangular wire 3 from which the resin is to be peeled, leaving the film remaining portions 41 and 42.

By performing the same operation on the rotary grindstones 8 and 9 of the second peeling portion 107, the remaining film portions 41 and 42 can be removed from a predetermined area of the rectangular wire 3 where the resin is to be peeled. After that, if a predetermined portion (for example, the center in the extending direction) of the region where the resin is to be peeled off is cut by the cutting section 108, the flat wire 3 having a predetermined length one after another and having both ends peeled off by the automation process can be obtained. it can.

In this case, if the distance between the rotary grindstones 1 and 2 and the rotary grindstones 8 and 9 in the extending direction is an integral multiple of the length of the cutting wire, the rectangular wire 3 Can be synchronized with the feed stop timing of the flat wire 3 with respect to the rotating grindstones 8 and 9, and the productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which four main surfaces of a rectangular wire and a diagonal portion are ground by a pair of rotary grindstones.

FIG. 2 is a schematic sectional view of FIG.

FIG. 3 is a cross-sectional view of a flat wire ground with a pair of rotary grindstones of FIG. 1;

FIG. 4 is a schematic cross-sectional view showing a step of removing the remaining electrically insulating resin film with another pair of rotating grindstones.

FIG. 5 is a schematic sectional view showing a modified embodiment.

FIG. 6 is a schematic sectional view showing a modified embodiment.

FIG. 7 is a schematic view showing an automation line for automating a resin peeling step of the present invention.

FIG. 8 is a schematic cross-sectional view showing a conventional helical reamer type resin film peeling machine for removing a round wire electric insulating resin film.

9 is a plan view of the helical reamer type resin film peeling machine of FIG.

[Explanation of symbols]

Reference numerals 1 and 2 denote rotating grindstones, 3 denotes a rectangular wire (covered wire), 4 denotes an electrically insulating resin film, 5 denotes a cylindrical surface portion, 6 denotes a disk surface portion, 7 denotes a cone-shaped surface portion, 8, 9 denotes a rotary grinding stone, 31, 32. Are the main surfaces on the wide side of the rectangular wire, 33 and 34 are the main surfaces on the narrow side of the rectangular wire 3, 35
38 are corners of the flat wire 3.

Continued on the front page (72) Inventor Yu Sugiyama 1-1-1, Showa-cho, Kariya-shi, Aichi F-term in DENSO Corporation (reference) 5H615 AA01 BB02 PP01 PP12 QQ02 SS03 SS08 SS10 TT03

Claims (9)

[Claims] 1. Production of a coil conductor for a rotating electric machine having a main portion in which a conductor wire is covered with an electrically insulating resin film and a tip portion made of the conductor wire exposed by peeling the electrically insulating resin film. In the method, each corner portion has a substantially rectangular cross section having a substantially circular arc shape in a direction perpendicular to the longitudinal direction, and a covering wire on which the electrically insulating resin film is applied is linearly arranged on the entire surface; One of the corners and one of the two substantially flat main surfaces adjacent to each other across the one corner has a ground surface having a shape capable of simultaneously and individually contacting the two main surfaces, and the axial direction with respect to the covering wire is Rotating the rotating grindstone arranged at a substantially right angle posture, extending the covered wire with respect to the rotating grindstone while contacting the grinding surface of the rotating grindstone with a predetermined area in the extending direction of the covered wire. Relative to the line direction to move the A two-sided peeling step of peeling the electrical insulating resin film of the one corner and the two main surfaces is performed simultaneously or sequentially on all of the corners in the predetermined region, and the electrical insulating resin film is A method for manufacturing a coil conductor for a rotating electric machine, wherein the predetermined area of the stripped covered wire is the tip end of the coil conductor. 2. The method for manufacturing a coil conductor for a rotating electric machine according to claim 1, wherein the grinding surface of the rotating grindstone has a cylindrical surface extending in an axial direction, a disk surface extending in a radial direction, and the cylindrical surface and the disk. A conical surface portion having a diameter increasing from the cylindrical surface portion toward the disk surface portion between the surface portions, wherein the cylindrical surface portion grinds the main surface on the wide side of the covered wire, and the disk surface portion includes: A method of manufacturing a coil conductor for a rotating electric machine, wherein the main surface on the narrow side of the covered wire is ground. 3. The method for manufacturing a coil conductor for a rotating electric machine according to claim 1, wherein a pair of the rotating grindstones are arranged diagonally across the covered wire.
A method of manufacturing a coil conductor for a rotating electrical machine, wherein four main surfaces and two corners of the predetermined region of the covered wire are simultaneously ground. 4. The method of manufacturing a coil conductor for a rotating electric machine according to claim 3, wherein another pair of said rotating grindstones different from said pair of rotating grindstones are diagonally arranged with said coated wire interposed therebetween. A method of manufacturing a coil conductor for a rotating electric machine, wherein two remaining corners different from the two corners of the covered wire are ground with a pair of rotating grindstones. 5. The method for manufacturing a coil conductor for a rotating electrical machine according to claim 1, wherein the electrically insulating resin film in the predetermined area other than the end of the linearly arranged covered wire is rotated. A method for manufacturing a coil conductor for a rotating electric machine, wherein the predetermined area of the covered wire is cut off by the grinding wheel, and the predetermined area of the covered wire is used as the tip of the coil conductor. 6. The method for manufacturing a coil conductor of a rotating electric machine according to claim 1, wherein the rotating grindstone is provided on an exposed surface of the conductor wire when grinding the electrically insulating resin film. A method for manufacturing a coil conductor of a rotating electrical machine, wherein the method has a surface roughness and a rotation speed that form a large number of linear marks in a longitudinal direction. 7. The method for manufacturing a coil conductor for a rotating electric machine according to claim 1, wherein the rotating grindstone has a matte surface on an exposed surface of the conductor wire when grinding the electrically insulating resin film. A method for manufacturing a coil conductor of a rotating electric machine, wherein the method has a surface roughness and a rotation speed for forming a minute fine uneven portion. 8. A rotary electric machine having a main part in which a conductor wire made of a rectangular wire is covered with an electrically insulating resin film, and a tip part made of the conductor wire exposed by peeling off the electrically insulating resin film. The coil conductor of a rotating electrical machine, wherein the surface of the tip portion has a large number of linear marks extending in a longitudinal direction. 9. A rotating electric machine having a main part in which a conductor wire made of a rectangular wire is covered with an electrically insulating resin film, and a tip part made of the conductor wire exposed by peeling off the electrically insulating resin film. The coil conductor of a rotary electric machine, wherein the surface of the tip portion has a matte-shaped minute uneven portion.