阅读说明：本技术 绝缘扁平导体、线圈及绝缘扁平导体的制造方法 (Insulated flat conductor, coil, and method for manufacturing insulated flat conductor ) 是由 漆原诚 樱井英章 于 2019-03-01 设计创作，主要内容包括：本发明的绝缘扁平导体(10,20)为具备扁平导体(11)及包覆所述扁平导体(11)的绝缘覆膜(15)的绝缘扁平导体(10,20),其特征在于,所述扁平导体(11)具有第一面(12a)及与所述第一面(12a)相对的第二面(12b),所述第一面(12a)与所述第二面(12b)相比更粗糙。(The insulated flat conductor (10, 20) of the present invention is an insulated flat conductor (10, 20) including a flat conductor (11) and an insulating coating (15) covering the flat conductor (11), wherein the flat conductor (11) has a first surface (12a) and a second surface (12b) opposite to the first surface (12a), and the first surface (12a) is rougher than the second surface (12 b).)

1. An insulated flat conductor comprising a flat conductor and an insulating coating covering the flat conductor,

the flat conductor has a first face and a second face opposite the first face, the first face being rougher than the second face.

2. The insulated flat conductor of claim 1,

the surface roughness Ra of the first surface of the flat conductor is 0.14 [ mu ] m or more.

3. The insulated flat conductor of claim 1 or 2,

the second surface of the flat conductor has a surface roughness Ra of 0.07 [ mu ] m or less.

4. A coil formed by winding the insulated flat conductor according to any one of claims 1 to 3 such that the first surface of the flat conductor is inside.

5. A method for manufacturing an insulated flat conductor according to any one of claims 1 to 3, comprising the steps of:

preparing a flat conductor having a first surface and a second surface opposite to the first surface;

roughening the first surface of the flat conductor so as to be rougher than the second surface; and

and coating the surface of the flat conductor subjected to the roughening treatment with an insulating coating film.

Technical Field

The present invention relates to an insulated flat conductor, a coil, and a method for manufacturing the insulated flat conductor.

The present application claims priority based on patent application No. 2018-038670, filed in japan on 3/5/2018, and the contents thereof are incorporated herein by reference.

Background

The insulated flat conductor is formed by coating a flat conductor having a substantially rectangular cross section with an insulating coating. The coil formed of the insulated flat conductor is used as an electric coil for various electric devices such as a motor and a transformer. A coil formed of an insulated flat conductor has an advantage that a gap between conductors can be reduced and an occupation volume ratio of the conductor in the coil can be increased, as compared with a coil formed of an insulated round wire conductor having a substantially circular cross section.

However, the insulated flat conductor has the following problems: when the wire is bent into a coil shape, the insulating coating is more likely to peel off than an insulated round wire conductor. Therefore, studies have been made to improve the adhesion between the flat conductor and the insulating coating.

Patent document 1 discloses a copper-resin composite having excellent adhesion between copper and a resin, the composite including a metal made of copper or a copper alloy and a resin bonded to the metal through a nanoporous layer formed on the metal. Patent document 1 describes a method of forming a copper oxide nanoporous layer by irradiating a surface of a metal made of copper or a copper alloy with laser light.

Patent document 2 discloses an insulated wire including an insulating coating composed of an innermost insulating coating formed by applying a silane coupling agent to the outer periphery of a conductor and an outermost insulating coating formed by applying and sintering a wire enamel to the innermost insulating coating. Patent document 2 describes, as a method for roughening the surface roughness Ra to the range of 0.2 to 1.0 μm while setting the average surface roughness Ra of the conductor to be 0.2 to 1.0 μm, an etching treatment, roughening by copper plating, and surface polishing by sandblasting.

Patent document 1: japanese laid-open patent publication No. 2015-082401 (A)

Patent document 2: japanese patent No. 5102541 publication (B)

In order to improve the adhesion between the insulating coating and the flat conductor, it is effective to form a nano-porous layer on the surface of the flat conductor as described in patent document 1 or to roughen the surface of the flat conductor as described in patent document 2. However, if the entire flat conductor is roughened, foreign matter or the like is likely to adhere to the surface of the flat conductor, and the foreign matter or the like is likely to remain even if cleaned. If foreign matter adheres to the surface of the flat conductor, it is difficult to uniformly coat the surface of the flat conductor with the insulating coating, and there is a possibility that a defect of the insulating coating occurs.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object thereof is to provide an insulated flat conductor in which defects of an insulating coating are not easily generated and adhesion between the flat conductor and the insulating coating is high, and a coil manufactured using the insulated flat conductor. Another object of the present invention is to provide a method for manufacturing an insulated flat conductor, in which defects of an insulating coating are not easily generated and adhesion between the flat conductor and the insulating coating is high.

In order to solve the above problem, an insulated flat conductor according to an aspect of the present invention (hereinafter referred to as "an insulated flat conductor of the present invention") is an insulated flat conductor including a flat conductor and an insulating coating covering the flat conductor, and the flat conductor includes a first surface and a second surface opposite to the first surface, and the first surface is rougher than the second surface.

According to the insulated flat conductor of the present invention having such a configuration, the first surface of the flat conductor is rougher than the second surface, and the contact area between the first surface and the insulating coating is large, so that the adhesion between the flat conductor and the insulating coating is improved. On the other hand, since the second surface is smoother than the first surface and foreign matter or the like is less likely to adhere thereto, defects of the insulating film are less likely to occur when the insulating film is formed.

In the insulated flat conductor according to the present invention, it is preferable that the surface roughness Ra of the first surface of the flat conductor is 0.14 μm or more.

In this case, since the surface roughness Ra of the first surface of the flat conductor is 0.14 μm or more, the contact area with the insulating film is large, and thus the adhesion to the insulating film is more reliably improved.

In the insulated flat conductor according to the present invention, it is preferable that the surface roughness Ra of the second surface of the flat conductor is 0.07 μm or less.

In this case, since the surface roughness Ra of the second surface of the flat conductor is 0.07 μm or less, foreign matter or the like is more reliably less likely to adhere, and thus, defects of the insulating coating are more reliably less likely to occur when the insulating coating is formed.

A coil according to another aspect of the present invention (hereinafter referred to as "the coil of the present invention") is formed by winding the insulated flat conductor so that the first surface of the flat conductor is located inside.

According to the coil of the present invention having such a configuration, since the insulated flat conductor is wound such that the first surface of the flat conductor is located inside, the first surface of the flat conductor and the insulating coating are less likely to peel off.

A method for manufacturing an insulated flat conductor according to another aspect of the present invention (hereinafter referred to as "the method for manufacturing an insulated flat conductor according to the present invention") is the method for manufacturing an insulated flat conductor, including: preparing a flat conductor having a first surface and a second surface opposite to the first surface; roughening the first surface of the flat conductor so as to be rougher than the second surface; and coating the surface of the flat conductor subjected to the roughening treatment with an insulating coating film.

According to the method for manufacturing an insulated flat conductor of the present invention having such a configuration, since the surface of the flat conductor that has been roughened so that the first surface of the flat conductor is rougher than the second surface is coated with the insulating coating, the contact area between the first surface and the insulating coating can be increased, and the adhesion between the flat conductor and the insulating coating can be improved. Further, since the second surface of the flat conductor is smoother than the first surface and foreign matter or the like is less likely to adhere thereto, defects of the insulating coating are less likely to occur when the insulating coating is formed. Therefore, it is possible to obtain an insulated flat conductor in which defects of the insulating coating are not easily generated and adhesion between the flat conductor and the insulating coating is high.

According to the present invention, it is possible to provide an insulated flat conductor in which defects of an insulating coating are not easily generated and adhesion between the flat conductor and the insulating coating is high, and a coil using the insulated flat conductor.

Further, according to the present invention, it is possible to provide a method for manufacturing an insulated flat conductor in which defects of an insulating coating are not easily generated and adhesion between a flat conductor and the insulating coating is high.

Drawings

Fig. 1 is a cross-sectional view of an insulated flat conductor as a first embodiment of the present invention.

Fig. 2 is a perspective view illustrating a method of manufacturing a coil using an insulated flat conductor according to a first embodiment of the present invention.

Fig. 3 is a cross-sectional view of an insulated flat conductor as a second embodiment of the present invention.

Fig. 4 is a perspective view illustrating a method of manufacturing a coil using an insulated flat conductor according to a second embodiment of the present invention.

Detailed Description

Hereinafter, an insulated flat conductor, a coil, and a method for manufacturing an insulated flat conductor according to an embodiment of the present invention will be described with reference to the drawings.

[ first embodiment ]

Fig. 1 is a cross-sectional view of an insulated flat conductor as a first embodiment of the present invention.

As shown in fig. 1, the insulated flat conductor 10 includes a flat conductor 11 and an insulating coating 15 covering the flat conductor 11.

The flat conductor 11 has a substantially rectangular cross section, and has a long-side surface 12 and a short-side surface 13. In the present embodiment, one of the short-side surfaces 13 is a first surface 13a, and the first surface 13a is made rougher than a second surface 13b opposed to the first surface 13 a.

The first surface 13a is a rough surface, so that the contact area with the insulating film 15 is larger than the second surface 13b and the adhesion with the insulating film 15 is high. The surface roughness Ra of the first surface 13a is preferably 0.14 μm or more, and more preferably 0.48 μm or more. When the surface roughness Ra of the first surface 13a is 0.14 μm or more, the contact area between the first surface 13a and the insulating film is large.

If the surface roughness Ra of the first surface 13a is too large, a gap may be easily formed between the first surface 13a and the insulating film 15. Therefore, the surface roughness Ra of the first surface 13a is preferably 1.5 μm or less.

The second surface 13b is a flat surface, and therefore, foreign matter or the like is less likely to adhere thereto than the first surface 13 a. The surface roughness Ra of the second surface 13b is preferably 0.07 μm or less. When the surface roughness Ra is 0.07 μm or less, foreign matters and the like are more reliably less likely to adhere to the second surface 13 b.

The surface roughness Ra of the second surface 13b may be 0.03 μm or more. Even if the surface roughness Ra of the second surface 13b is set to be less than 0.03 μm, the effect of making foreign matter or the like less likely to adhere is saturated, and if the surface is smoothed to a surface roughness Ra of less than 0.03 μm, the processing cost for smoothing may be increased.

The long-side surface 12 may be a rough surface or a smooth surface. The long-side surface 12 may have a rough surface and a flat surface. In this case, the side contacting the first surface 13a is preferably a rough surface and the side contacting the second surface 13b is preferably a smooth surface. In order to improve the adhesion between the flat conductors 11 and the insulating coating 15 and reduce the adhesion of foreign matter and the like to the surfaces of the flat conductors 11, the long-side surface 12 is preferably formed as a rough surface in a range from a corner where the first surface 13a intersects the long-side surface 12 to 1/2 or less of the long side.

As the material of the flat conductor 11, a metal or an alloy that is generally used as a material of a flat conductor for a coil can be used. For example, copper alloy, aluminum, or aluminum alloy can be used.

The thickness of the insulating coating 15 covering the flat conductor 11 is preferably in the range of 10 μm to 50 μm.

As a material of the insulating film 15, for example, a polyester resin, a polyamideimide resin, a polyimide resin, a polyesterimide resin, an acrylic resin, an epoxy-acrylic resin, a polyester resin, a polyurethane resin, a fluorine resin, or the like can be used.

These materials may be used alone or in combination of two or more.

Next, a method for manufacturing the insulated flat conductor 10 according to the present embodiment will be described.

The method for manufacturing the insulated flat conductor 10 of the present embodiment includes: preparing a flat conductor 11 having a first surface 13a and a second surface 13b opposite to the first surface 13 a; a roughening step of roughening the first surface 13a of the flat conductor 11 to be rougher than the second surface 13 b; and a coating step of coating the surface of the roughened flat conductor 11 with an insulating coating 15.

As a method of performing the roughening treatment so that the first surface 13a of the flat conductor 11 is rougher than the second surface 13b in the roughening treatment step, for example, a method of immersing the first surface 13a in an etching solution so that the second surface 13b does not come into contact with the etching solution can be used.

Specifically, for example, a method of immersing only the first surface 13a of the flat conductor 11 in an etching solution, a method of shielding the second surface 13b and immersing the entire flat conductor 11 in an etching solution, or the like can be used.

The immersion time of the flat conductors 11 in the etching solution is preferably set to a time when the etching amount of the flat conductors 11 is in a range of 0.1 μm or more and 3.0 μm or less as the thickness of the flat conductors 11, and particularly preferably set to a time when the etching amount of the flat conductors 11 is in a range of 1.5 μm or more and 2.0 μm or less. When the immersion time of the flat conductor 11 in the etching solution is within this range, a rough surface having a surface roughness Ra excellent in adhesion to the insulating film 15 can be formed.

In the coating step, the method of coating the surface of the flat conductor 11 subjected to the roughening treatment with the insulating coating 15 is not particularly limited, and, for example, a coating method or an electrodeposition method can be used.

The coating method comprises the following steps: the coating layer is formed by applying varnish containing a resin for forming an insulating coating and a solvent to the surface of the conductor, and then the coating layer is heated to sinter the insulating coating thus formed to the conductor.

The electrodeposition method is as follows: the method includes immersing a conductor and an electrode in an electrodeposition solution in which insulating resin particles having an electric charge are dispersed, applying a direct-current voltage between the conductor and the electrode to electrodeposit the insulating resin particles on the surface of the conductor to form an electrodeposition layer, and heating the electrodeposition layer to sinter the produced insulating coating film on the conductor.

Next, a coil manufactured by using the insulated flat conductor 10 will be described.

Fig. 2 is a perspective view illustrating a method of manufacturing a coil using the insulated flat conductor 10 as the first embodiment of the present invention.

When a coil is manufactured, as shown in fig. 2, an insulated flat conductor 10 is wound so that a first surface 13a (edge surface) of a flat conductor 11 is positioned inside, thereby manufacturing a coil (edgewise coil). When the insulated flat conductor 10 is wound, a compressive stress is applied to the inner side, but the flat conductor 11 and the insulating coating 15 are less likely to be peeled off by winding the insulated flat conductor 10 so that the first surface 13a having high adhesion to the insulating coating 15 is located on the inner side. The method of winding the insulated flat conductor 10 is not particularly limited, and a known method generally used for manufacturing a normal edgewise coil can be used.

According to the insulated flat conductor 10 of the first embodiment having the above configuration, the first surface 13a, which is one of the short-side surfaces 13 of the flat conductor 11, is rougher than the second surface 13b, and the contact area between the first surface 13a and the insulating coating 15 is large, so that the adhesiveness between the first surface 13a and the insulating coating 15 is improved. On the other hand, since the second surface 13b is a smoother surface than the first surface 13a and foreign matter or the like is less likely to adhere thereto, defects in the insulating film 15 are less likely to occur when the insulating film 15 is formed.

In the insulated flat conductor 10 of the present embodiment, by setting the surface roughness Ra of the first surface 13a of the flat conductor 11 to 0.14 μm or more, the contact area with the insulating coating 15 is large, and thus the adhesion to the insulating coating 15 is more reliably improved.

In the insulated flat conductor 10 of the present embodiment, by setting the surface roughness Ra of the second surface 13b of the flat conductor 11 to 0.07 μm or less, foreign matter and the like are less likely to adhere, and thus defects in the insulating coating 15 are more reliably less likely to occur when the insulating coating 15 is formed.

In addition, since the coil of the present embodiment is formed by winding the flat insulated conductor 10 so that the first surface 13a of the flat conductor 11 is on the inside, the first surface 13a of the flat conductor 11 and the insulating coating 15 are less likely to peel off even when a compressive stress is applied thereto due to the winding.

Further, according to the roughening treatment method of the flat conductor of the present embodiment, since the surface of the flat conductor 11 roughened so that the first surface 13a of the flat conductor 11 is rougher than the second surface 13b is coated with the insulating coating 15, the contact area between the first surface 13a and the insulating coating 15 can be increased, and thus the adhesion between the flat conductor 11 and the insulating coating 15 can be improved. Further, since the second surface 13b of the flat conductor 11 is smoother than the first surface 13a and foreign matter or the like is less likely to adhere thereto, defects in the insulating coating 15 are less likely to occur when the insulating coating 15 is formed. This makes it possible to obtain the insulated flat conductor 10 in which defects of the insulating coating 15 are not easily generated and which has high adhesion between the flat conductor 11 and the insulating coating 15.

[ second embodiment ]

Next, a second embodiment of the present invention will be explained. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

Fig. 3 is a cross-sectional view of an insulated flat conductor as a second embodiment of the present invention.

As shown in fig. 3, the insulated flat conductor 20 includes a flat conductor 11 and an insulating coating 15 covering the flat conductor 11, and the flat conductor 11 has a substantially rectangular cross section and has a long-side surface 12 and a short-side surface 13.

In the present embodiment, one of the long-side surfaces 12 is a first surface 12a, and the first surface 12a is made rougher than a second surface 12b opposed to the first surface 12a, thereby improving adhesion between the first surface 12a and the insulating film 15. The preferable values of the surface roughness Ra of the first surface 12a and the second surface 12b are the same as those of the first surface 13a and the second surface 13b of the first embodiment.

The short side surface 13 may be a rough surface or a smooth surface. The short-side surface 13 may have a rough surface and a flat surface. In this case, the side contacting the first surface 12a is preferably a rough surface and the side contacting the second surface 12b is preferably a smooth surface. In order to improve the adhesion between the flat conductors 11 and the insulating coating 15 and reduce the adhesion of foreign matter and the like to the surfaces of the flat conductors 11, the short-side surface 13 is preferably formed as a rough surface in a range from a corner where the first surface 12a intersects the short-side surface 13 to 1/2 or less of the short side.

The thickness and material of the insulating coating 15 are the same as those in the first embodiment.

The method for manufacturing the insulated flat conductor 20 according to the present embodiment is the same as the method for manufacturing the insulated flat conductor 10 described in the first embodiment except that the roughening treatment is performed so that the first surface 12a of the flat conductor 11 is rougher than the second surface 12b in the roughening treatment step. In the roughening treatment step, as in the case of the first embodiment, the method of treating the first surface 12a of the flat conductor 11 to make it rougher than the second surface 12b can be used by immersing the first surface 12a in the etching solution so that the second surface 12b does not come into contact with the etching solution.

Next, a coil manufactured by using the insulated flat conductor 20 will be described.

Fig. 4 is a perspective view illustrating a method of manufacturing a coil using the insulated flat conductor 20 as the second embodiment of the present invention.

When a coil is manufactured, as shown in fig. 4, an insulated flat conductor 20 is wound so that the first surface 12a (flat surface) of the flat conductor 11 is on the inside to manufacture a coil (flat wire coil). When the flat insulated conductor 20 is wound, a compressive stress is applied to the inside, but the flat conductor 11 and the insulating coating 15 are less likely to be peeled off by winding the flat insulated conductor 20 so that the first surface 12a having high adhesion to the insulating coating 15 is located inside. The method of winding the insulated flat conductor 20 is not particularly limited, and a known method generally used for producing a flat coil can be used.

According to the insulated flat conductor 20 of the second embodiment having the above configuration, the first surface 12a, which is one of the long-side surfaces 12 of the flat conductor 11, is rougher than the second surface 12b, and the contact area between the first surface 12a and the insulating coating 15 is large, so that the adhesiveness between the first surface 12a and the insulating coating 15 is improved. On the other hand, since the second surface 12b is a smoother surface than the first surface 12a and foreign matter or the like is less likely to adhere thereto, defects in the insulating film 15 are less likely to occur when the insulating film 15 is formed.

In the insulated flat conductor 20 of the present embodiment, by setting the surface roughness Ra of the first surface 12a of the flat conductor 11 to 0.14 μm or more, the contact area with the insulating coating 15 is large, and thus the adhesion to the insulating coating 15 is more reliably improved.

In the insulated flat conductor 20 of the present embodiment, by setting the surface roughness Ra of the second surface 12b of the flat conductor 11 to 0.07 μm or less, foreign matter and the like are less likely to adhere, and thus defects in the insulating coating 15 are more reliably less likely to occur when the insulating coating 15 is formed.

In addition, since the coil of the present embodiment is formed by winding the flat insulated conductor 20 so that the first surface 12a of the flat conductor 11 is on the inside, the first surface 12a of the flat conductor 11 and the insulating coating 15 are less likely to peel off.

Further, according to the roughening treatment method of the flat conductor of the present embodiment, since the surface of the flat conductor 11 roughened so that the first surface 12a of the flat conductor 11 is rougher than the second surface 12b is coated with the insulating coating 15, the contact area between the first surface 12a and the insulating coating 15 can be increased, and thus the adhesion between the flat conductor 11 and the insulating coating 15 can be improved. Further, since the second surface 12b of the flat conductor 11 is smoother than the first surface 12a and foreign matter or the like is less likely to adhere thereto, defects in the insulating coating 15 are less likely to occur when the insulating coating 15 is formed. This makes it possible to obtain the insulated flat conductor 20 in which defects of the insulating coating 15 are less likely to occur and which has high adhesion between the flat conductor 11 and the insulating coating 15.

The embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and can be modified as appropriate within a range not departing from the technical spirit of the present invention.