WO2016027847A1 - Insulated electric wire and method for manufacturing rotary electrical machine using same - Google Patents

Abstract

An insulated electric wire 100 in one embodiment of the present invention is provided with a conductor 101 and an insulation layer 102 formed around the conductor 101, the insulation layer 102 having an insulation film 103 formed by fusion-extruding, and coating therewith, polyphenylene sulfide resin the viscosity of which, when the temperature is 310℃ and the shear velocity is 243 sec^-1, is 300-1150 Pa・s inclusive, the crystallinity of the insulation film 103 being 85% or more. A method for manufacturing a rotary electrical machine in another embodiment of the present invention includes heating the insulated electric wire 100 to a temperature of 120-200℃ inclusive after assembling the armature of the rotary electrical machine while applying deformation processing to the insulated electric wire 100.

Description

Insulated wire and method of manufacturing rotating electrical machine using the same

The present invention relates to an insulated wire used for a winding of an industrial motor and the like, and a method of manufacturing a rotating electrical machine using the insulated wire.

In recent years, in industrial motors typified by drive motors such as electric vehicles and hybrid vehicles, drive voltage increases for higher output and inverter drive for improving power performance are rapidly progressing.

However, due to the superposition of the high drive voltage and inverter surge voltage associated with the drive voltage increase and inverter drive of industrial motors, the risk of partial discharge occurring in the insulated wires that make up the windings of industrial motors increases. ing.

In particular, in an insulated wire having a low partial discharge start voltage (PDIV: Partial Discharge Acceptance Voltage), a partial discharge occurs even at a low voltage, and the insulating coating that ensures the insulation performance of the insulated wire is gradually eroded by the partial discharge. There is a concern that it will eventually result in poor insulation.

This partial discharge start voltage can be increased by lowering the relative dielectric constant of the insulating film than before or by increasing the film thickness of the insulating film.

In order to increase the partial discharge start voltage by lowering the relative dielectric constant of the insulating film than before, the relative dielectric constant of fluorine-containing polymers (for example, polyimide (PI) resin or polyamideimide (PAI) resin) is conventionally increased. It is conceivable to use insulation coatings made of lower materials, but these materials are expensive and lead to higher prices for industrial motors, so use insulation coatings made of these materials It is difficult.

On the other hand, when increasing the partial discharge start voltage by increasing the film thickness of the insulating film, the film thickness of the insulating film is changed from 100 μm to 200 μm so that it can withstand the high drive voltage of an industrial motor and inverter drive. It is necessary to make it as thick as possible.

However, in the normal enamel coating method, since the film thickness of the insulating film that can be formed by one coating is about several μm, in order to increase the film thickness of the insulating film from about 100 μm to about 200 μm, It is necessary to significantly increase the number of paintings than before, and the price of industrial motors increases due to the increase in the number of paintings. Therefore, it is not practical to form an insulating coating by the usual enamel coating method. There is also a problem that the risk of occurrence of defects such as the formation of granular defects in the insulating coating increases due to the increase in the thickness.

Considering this point, it has been studied to make the insulating film thicker than before by melt-extrusion coating a thermoplastic resin around the conductor to form the insulating film.

Here, as the thermoplastic resin, a resin such as a polyphenylene sulfide (PPS) resin, a polyether sulfone (PES) resin, a polyetherimide (PEI) resin, or a polyetheretherketone (PEEK) resin may be used. Of these resins, polyphenylene sulfide has the characteristics required for insulating coatings such as chemical resistance, rigidity, and electrical insulation, and is cheaper than other engineering plastics. Resin is promising.

Polyphenylene sulfide resin is a crystalline polymer, and it is known that chemical resistance and heat resistance are improved by crystallization. Therefore, polyphenylene sulfide resin is molded into a desired shape (for example, injection molding or extrusion molding). When the polyphenylene sulfide resin is not crystallized later, the polyphenylene sulfide resin is usually heated to a temperature equal to or higher than the crystallization temperature, thereby increasing the crystallinity of the polyphenylene sulfide resin to produce a product.

In winding applications for industrial motors, it is necessary to deform or insulate the insulated wire by bending or stretching the insulated wire. This deformation is usually applied to the insulated wire with a low degree of crystallinity of the insulation coating. Applied. The reason for this is that with an insulated wire having an insulation coating formed by melt extrusion coating of polyphenylene sulfide resin, the mechanical properties such as bending properties and elongation properties of the insulation coating when deforming the insulated wire are polyphenylene sulfide. This is because the lower the crystallinity of the insulating coating made of resin, the better.

After the deformation process, the chemical resistance and heat resistance are improved by heating the insulating film to a temperature higher than the crystallization temperature to increase the crystallinity of the insulating film.

For example, Patent Document 1 assembles an armature of a rotating electric machine that involves deformation processing of an insulating wire in a state where the polyphenylene sulfide resin composition of the extrusion-coated resin layer formed on the outer periphery of the conductor is not crystallized. The manufacturing method which crystallizes the polyphenylene sulfide resin composition of an insulated wire by heating the insulated wire after completion | finish to the temperature of 120 degreeC or more is disclosed.

JP 2010-055964 A

In the manufacturing method of Patent Document 1, when the crystallinity of the insulating film made of polyphenylene sulfide resin is low and the hardness thereof is low (insulating film is soft), in the assembly of the armature of the subsequent rotating electric machine, the insulated wire is attached to the core slot. There is a risk of poor insulation due to wear (for example, scratches or indentations) generated in the insulating film due to pressing or rubbing against a molding jig or the like during insertion or coil end molding.

In order to prevent such abrasion of the insulating film, if the crystallinity of the insulating film is increased and its hardness is increased before deformation processing, the insulating film may be cracked or broken. .

An object of the present invention is to provide an insulated wire having high workability and wear resistance while the insulating coating is formed of polyphenylene sulfide resin.

Another object of the present invention is to provide a method of manufacturing a rotating electrical machine using the insulated wire.

The insulated wire in one embodiment of the present invention includes a conductor and an insulating layer formed around the conductor, and the insulating layer has a temperature of 310 ° C. and a shear rate of 243 sec ⁻¹ . It has an insulating film formed by melt extrusion coating of a polyphenylene sulfide resin having a viscosity of 300 Pa · s or more and 1150 Pa · s or less, and the insulating film has a crystallinity of 85% or more.

The insulating coating may be an outermost layer of the insulating layer.

The insulating layer may include an enamel baking layer formed around the conductor and the insulating coating formed around the enamel baking layer.
The polyphenylene sulfide resin may have a weight average molecular weight such that the viscosity is from 300 Pa · s to 1150 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ .

The manufacturing method of the rotary electric machine in other embodiment of this invention includes heating the said insulated wire to 120 to 200 degreeC, after assembling the armature of a rotary electric machine, deforming the said insulated wire. .

According to one embodiment of the present invention, it is possible to provide an insulated wire having high workability and wear resistance while the insulating coating is formed of polyphenylene sulfide resin, and a method of manufacturing a rotating electrical machine using the insulated wire.

It is a perspective view which shows the insulated wire which concerns on this invention.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, an insulated wire 100 according to a preferred embodiment of the present invention includes a conductor 101 and an insulating layer 102 formed around the conductor 101.

The conductor 101 is made of a highly conductive metal such as copper (eg, low oxygen copper or oxygen-free copper) or aluminum, and has a rectangular wire having a rectangular cross section, a round wire having a circular cross section, or a circular cross section. It consists of a stranded wire formed by twisting a plurality of round wires or the like.

The insulating layer 102 has an insulating coating 103 formed by melt extrusion coating a polyphenylene sulfide resin having a viscosity of 300 Pa · s to 1150 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ^−1. The insulating coating 103 needs to have a crystallinity of 85% or more.

Here, the degree of crystallinity [%] is the crystallization heat (exothermic enthalpy) of cold crystallization when measured by raising the temperature from room temperature (40 ° C.) by differential scanning calorimetry (DSC: Differential Scanning Calorimetry) [J / When g] is Hc and heat of fusion (endothermic enthalpy) [J / g] by differential scanning calorimetry is Hm, it is expressed by equation (1).

The reason why the crystallinity of the insulating coating 103 made of polyphenylene sulfide resin before the deformation processing of the insulated wire 100 is 85% or more is that the crystallinity of the insulating coating 103 before the deformation processing of the insulated wire 100 is 85. If it is less than%, the wear resistance of the insulated wire 100 is reduced, so that when the armature of the rotating electrical machine is assembled, the insulation coating 103 is worn and the thickness of the insulation coating 103 is reduced. This is because electrical insulation characteristics cannot be obtained.

In order to improve the wear resistance of the insulated wire 100 to such an extent that the insulation coating 103 is not worn when the armature of the rotating electrical machine is assembled, the insulation coating 103 before the deformation of the insulated wire 100 is performed. The crystallinity of is desirably 90% or more.

In order to set the crystallization degree of the insulating film 103 before the deformation process to the insulated wire 100 to 85% or more, the insulating film 103 is preferably heated to a temperature equal to or higher than the cold crystallization temperature of the polyphenylene sulfide resin.

Specifically, the insulation film 103 is heated to a cold crystallization temperature of 120 ° C. or more and 200 ° C. or less, so that the degree of crystallinity of the insulation film 103 before the deformation of the insulated wire 100 is 85% or more. It becomes possible.

At this time, even if the insulating film 103 is heated to 200 ° C. or higher, the polyphenylene sulfide resin can be crystallized to make the insulating film 103 have a crystallinity of 85% or more. Since the insulating coating 103 may be deformed by lowering, it is desirable to increase the crystallinity of the insulating coating 103 by heating the insulating coating 103 to 200 ° C. or lower.

The heating of the insulating coating 103 may be performed after the insulated wire 100 is manufactured or during the manufacturing of the insulated wire 100.

Usually, when the degree of crystallinity of the insulating coating 103 before the deformation processing is performed on the insulated wire 100 is 85% or more, the insulating coating 103 is less likely to be worn due to its increased hardness. Compared to the case where the degree of crystallinity of the insulating coating 103 before the deformation processing of the electric wire 100 is less than 85%, a machine such as a bending characteristic and an elongation characteristic of the insulating coating 103 when the insulating electric wire 100 is deformed. Therefore, there is a high possibility that the insulating coating 103 will be cracked or broken when the insulated wire 100 is deformed.

Accordingly, the present inventors have made extensive studies on the insulated wire 100 including the insulating coating 103 formed by melt extrusion coating of polyphenylene sulfide resin, and as a result, the viscosity of the polyphenylene sulfide resin constituting the insulating coating 103 is increased. It has been found that by setting the predetermined range, it is possible to improve the mechanical characteristics of the insulating coating 103 and improve the workability of the insulated wire 100.

That is, the present inventors have formed a polyphenylene sulfide resin having a viscosity of 300 Pa · s or more and 1150 Pa · s or less when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ and is formed by melt extrusion coating and the insulated wire 100. The insulating film 103 having a crystallinity of 85% or more before being deformed is excellent in mechanical characteristics, and by adopting the insulating film 103, the wear resistance of the insulated wire 100 is secured. It has been found that workability can be improved.

The viscosity of the polyphenylene sulfide resin can be adjusted by changing the weight average molecular weight of the polyphenylene sulfide resin.

By the way, in order to increase the space factor of the conductor 101 in the core slot, the insulated wire 100 preferably employs the conductor 101 made of a rectangular wire having a rectangular cross section, and includes the conductor 101 made of a rectangular wire having a rectangular cross section. When the insulated wire 100 is subjected to deformation processing accompanied by edgewise bending, a large stress is applied to the insulating coating 103, but the viscosity at a temperature of 310 ° C. and a shear rate of 243 sec ⁻¹ is 300 Pa · s or more and 1150 Pa · s or less. The insulating coating 103 is cracked or broken by adopting the insulating coating 103 that is formed by melt extrusion coating of the polyphenylene sulfide resin and having a crystallinity of 85% or more before the insulated wire 100 is deformed. It is possible to prevent the occurrence of the It has also been found that it can be applied.

Moreover, even if the insulated wire 100 having the conductor 101 made of a rectangular wire having a rectangular cross section is subjected to deformation processing accompanied by edgewise bending after being stretched by about 20% to 30%, the insulating coating 103 is not cracked. There was no occurrence of tearing and the like, and it was possible to appropriately perform deformation processing accompanied with edgewise bending.

In contrast, a polyphenylene sulfide resin having a viscosity of less than 300 Pa · s at a temperature of 310 ° C. and a shear rate of 243 sec ⁻¹ is formed by melt extrusion coating and crystallized before the insulated wire is deformed. When an insulating film having a degree of conversion of 85% or more was employed, the insulating film was broken when the insulated wire was stretched by about 10%, and could not withstand deformation processing involving edgewise bending. .

In addition, a polyphenylene sulfide resin having a viscosity of more than 1150 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is formed by melt extrusion coating, and the degree of crystallinity before the deformation processing is performed on the insulated wire. When an insulating coating of 85% or more is employed, the workability when melt-extrusion coating the conductor 101 is reduced because the melt viscosity of the polyphenylene sulfide resin is large and the fluidity is poor.

For the above reasons, in the insulated wire 100 according to the present embodiment, a polyphenylene sulfide resin having a viscosity of 300 Pa · s to 1150 Pa · s at a temperature of 310 ° C. and a shear rate of 243 sec ⁻¹ is melt-extruded. Insulating film 103 having a crystallinity of 85% or more before being deformed is formed.

In addition, the polyphenylene sulfide resin refers to a resin having a structure having a repeating unit represented by the chemical formula (1) in principle, but in addition to this structure, unless the flexibility and heat resistance of the resin are greatly impaired, A sulfoxide group or an ether group may be included, and a substituent may be included in the benzene ring. Furthermore, the molecular chain may contain a branched structure or a crosslinked structure via a thioether group or an ether group.

In addition, the insulating layer 102 may have another insulating film formed of a material different from that of the insulating film 103, a self-bonding layer, and the like. However, from the viewpoint of improving the workability and wear resistance of the insulated wire 100, the insulating coating 103 needs to be the outermost layer of the insulating layer 102.

For example, in the present embodiment, the insulating layer 102 has the insulating coating 103 formed directly around the conductor 101, but the enamel baking layer formed around the conductor 101; And an insulating coating 103 formed around the enamel baking layer. In this case, the insulating coating 103 is indirectly formed around the conductor 101 through the enamel baking layer.

The enamel baking layer may be a single layer or multiple layers, and a paint containing polyamideimide resin, polyimide resin, or polyesterimide (PEI) resin is applied to the surface of the conductor 101 and baked in a baking furnace. Is obtained.

When manufacturing a rotating electrical machine using the insulated wire 100 described so far, after assembling the armature of the rotating electrical machine while deforming the insulated wire 100, the insulated wire 100 is post-heated to 120 ° C. or higher. Thus, the residual stress of the insulated wire 100 is reduced, and the crystallinity of the insulating coating 103 made of polyphenylene sulfide resin is set to be larger than 85% and not larger than 100%.

Thereby, the chemical resistance of the insulated wire 100 can be improved. Originally, the insulated wire 100 employs the insulating coating 103 having a crystallinity of 85% or more before being deformed on the insulated wire 100, so that the chemical resistance is high. Chemical resistance can be further increased by post-heating to reduce the chemical resistance. At the same time, the chemical resistance can be improved by setting the crystallinity of the insulating coating 103 to be greater than 85% and not greater than 100%.

In addition, by increasing the heating temperature of the insulated wire 100, the residual stress of the insulated wire 100 is reduced and the heating time required for the crystallinity of the insulating coating 103 to be greater than 85% and less than 100% is shortened. However, if the heating temperature of the insulated wire 100 is too high, there is a high possibility that the insulating coating 103 will be deformed due to the low elastic modulus of the polyphenylene sulfide resin.

Therefore, the heating temperature of the insulated wire 100 is preferably 150 ° C. or higher and 200 ° C. or lower. Regarding the heating time, if the heating temperature of the insulated wire 100 is about 150 ° C., the heating time is about 10 minutes, and if the heating temperature of the insulated wire 100 is 200 ° C., it becomes about several minutes.

Therefore, it is possible to manufacture the rotating electrical machine while maintaining reliability such as chemical resistance and heat resistance.

As described above, the insulating coating 103 can be formed by directly melt-extrusion-coating polyphenylene sulfide resin around the conductor 101, but in order to improve the adhesion between the conductor 101 and the insulating coating 103. An adhesion treatment may be performed.

As the adhesion treatment, it is considered that the surface of the conductor 101 is chemically or physically modified, or an adhesion layer for improving the adhesion between the conductor 101 and the insulating coating 103 is interposed.

The adhesion layer is not limited, but polysulfone (PSU) resin, polyphenylsulfone (PPSU) resin, polyethersulfone (PES) resin, polyamide resin, polyetherimide resin, polyamideimide resin, polyimide Examples thereof include resins, epoxy resins, epoxy-modified olefin copolymer resins, maleic acid-modified olefin copolymer resins, and unsaturated carboxylic acid resins.

As described above, according to the present invention, it is possible to provide an insulated wire having high workability and wear resistance while the insulating coating is formed of polyphenylene sulfide resin, and a method for manufacturing a rotating electrical machine using the insulated wire.

Next, specific examples of the present invention will be described.

[Example 1]
Using a rectangular copper wire with a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 322 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 85% before the deformation of the wire was obtained.

[Example 2]
Using a rectangular copper wire with a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 322 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 100% before being deformed was obtained.

[Example 3]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 1120 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 86% before the deformation of the wire was obtained.

[Example 4]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 1120 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 100% before being deformed was obtained.

[Comparative Example 1]
Using a rectangular copper wire with a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 322 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 33% before being deformed was obtained.

[Comparative Example 2]
Using a rectangular copper wire with a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 322 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 65% before being deformed was obtained.

[Comparative Example 3]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 176 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire in which the crystallinity of the insulating film was 80% before the wire was deformed was obtained.

[Comparative Example 4]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 176 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 100% before being deformed was obtained.

[Comparative Example 5]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 1120 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 42% before the deformation of the wire was obtained.

[Comparative Example 6]
Using a rectangular copper wire having a conductor size of 1.5 mm × 3.0 mm, a polyphenylene sulfide resin having a viscosity of 1120 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ is directly above the rectangular copper wire. After forming an insulating film having a film thickness of about 150 μm by melt extrusion coating at about 300 ° C., insulation is achieved by adjusting the heating time when heating the insulated wire to 120 ° C. An insulated wire having a crystallinity of 100% before being deformed was obtained.

[Relationship between crystallinity and workability]
As for the crystallinity of the insulating coating, 5 g was sampled from the insulating coating made of polyphenylene sulfide resin formed in Examples 1 to 4 and Comparative Examples 1 to 6, and this sample was sealed in an aluminum pan and in a nitrogen atmosphere. After performing differential scanning calorimetry at a rate of temperature increase from 40 ° C. to 350 ° C. at 10 ° C./min, and determining the heat of crystallization and heat of fusion based on the peak area obtained as a result, the heat of crystallization And the heat of fusion were calculated by substituting them into Equation (1).

In addition, the workability of the insulated wires is 180 ° at a bending radius of 2 mm after applying 20% and 30% preliminary stretching to the insulated wires obtained in Examples 1 to 4 and Comparative Examples 1 to 6. The deformation process accompanied by edgewise bending was performed, and it was observed and evaluated whether or not the insulating coating had cracks or tears.

As can be seen from Table 1, the insulated wires obtained in Examples 1 to 4 using polyphenylene sulfide resin having a viscosity of 322 Pa · s or 1120 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ are Even if the insulation film has a crystallinity of 85% or more before the insulation wire is deformed, the insulation film is cracked or broken by deformation with edgewise bending after 30% pre-stretching. Was not generated and the workability was good.

In contrast, the insulated wires obtained in Comparative Examples 3 and 4 using a polyphenylene sulfide resin having a viscosity of 176 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ are obtained by crystallizing the insulating film. When the degree was 80% or more, the insulating film was broken by deformation processing accompanied by edgewise bending after pre-extension of 10% and 30%, and the workability was poor.

The viscosity of the polyphenylene sulfide resin is such that after the polyphenylene sulfide resin is filled in the barrel and melted, the polyphenylene sulfide resin is pushed down with a piston at a constant speed, and the polyphenylene sulfide resin is extruded through a die at the bottom of the barrel. The pressure of the polyphenylene sulfide resin was monitored by a pressure sensor arranged near the inlet of the die, the pressure when the equilibrium point was reached was recorded, and the pressure was calculated from this pressure and the flow rate ratio of the polyphenylene sulfide resin.

[Relationship between crystallinity and wear resistance]
The insulation resistance of the insulated wires was determined by separating the insulation coatings of the insulated wires obtained in Examples 1 to 4 and Comparative Examples 1 to 6 from the conductor to obtain insulation coating pieces having different crystallinity levels, and then insulating coatings. The film piece was evaluated by measuring the pencil hardness according to JIS K 5600-5-4.

As can be seen from Table 1, the higher the crystallinity of the insulation film, the more the pencil hardness is improved. In particular, the pencil hardness becomes H when the crystallinity of the insulation film before the deformation of the insulated wire is 85% or more. In addition, the wear resistance of the insulated wire is remarkably improved.

[Relationship between post-heating and chemical resistance]
The chemical resistance of the insulated wire was determined by subjecting the insulated wire obtained in Example 1 and Comparative Example 3 to deformation processing with an extension of 2%, and then changing only the insulated wire obtained in Example 1 to 120 ° C. By heating, the residual stress of the insulated wires is reduced and the crystallinity of the insulation film is set to 100%, and these insulated wires are immersed in xylene at 60 ° C. for 30 minutes, or automatic transmission oil at 150 ° C. ( After immersing in ATF (Automatic Transmission Fluid) for only 1000 hours, the state of occurrence of cracks and tears in the insulating coating was observed and evaluated.

As can be seen from Table 2, the insulated wire obtained in Example 1 maintains its appearance and has high chemical resistance regardless of whether it is immersed in xylene or automatic transmission fluid.

In contrast, the insulated wire obtained in Comparative Example 3 maintained its appearance when immersed in automatic transmission oil, but when immersed in xylene, cracked streaks were formed on the surface of the insulating coating. It has occurred.

INDUSTRIAL APPLICABILITY The present invention can be applied to an insulated wire used for a winding of an industrial motor or the like and a method for manufacturing a rotating electrical machine using the insulated wire.

100 Insulated wire 101 Conductor 102 Insulating layer 103 Insulating coating

Claims (5)

Conductors,
An insulating layer formed around the conductor, and
The insulating layer has an insulating coating formed by melt extrusion coating of a polyphenylene sulfide resin having a viscosity of 300 Pa · s to 1150 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ^−1. ,
The insulating coating is an insulated wire having a crystallinity of 85% or more. The insulated wire according to claim 1, wherein the insulating coating is an outermost layer of the insulating layer. The insulated wire according to claim 1 or 2, wherein the insulating layer includes an enamel baking layer formed around the conductor and the insulating coating formed around the enamel baking layer. A rotating electrical machine comprising: assembling an armature of a rotating electric machine while deforming the insulated electric wire according to any one of claims 1 to 3; and heating the insulated electric wire to 120 ° C to 200 ° C. Production method. 2. The insulated wire according to claim 1, wherein the polyphenylene sulfide resin has a weight average molecular weight of 300 Pa · s to 1150 Pa · s when the temperature is 310 ° C. and the shear rate is 243 sec ⁻¹ .

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