JP2005078883A - Complex enamel wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a complex enamel wire of a heat-resistant type excellent in high-frequency property, particularly, inverter surge-resistant property and coil winding property under high elongation. <P>SOLUTION: A polyester layer 3 or a heat-resistant polyester layer is formed at the outer periphery of a conductor 2. A polyester imide layer 4 is formed at the outer periphery of the polyester layer 3 or the heat-resistant polyester layer, and a self lubrication polyamide layer 5 is formed at the outer periphery of the polyester imide layer 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a composite enameled wire, and more particularly to a heat-resistant composite enameled wire excellent in high-frequency characteristics and winding property under high elongation.

  An enameled wire is an insulated wire formed by repeatedly applying and baking an enamel paint on the outer periphery of a conductor. This enameled wire is classified into a single-coated enameled wire and a composite enameled wire such as a double-coated enameled wire and a triple-coated enameled wire from the structural aspect.

  Single-coated enameled wire is obtained by applying and baking one type of enameled wire paint on the outer periphery of the conductor. Composite enameled wire is obtained by applying and baking two or more different types of enameled wire paint on the outer periphery of the conductor. It is.

  The purpose of compounding is to provide a wide range of properties as enameled wires by compensating for the properties and defects of each enameled wire by each paint, adding features, and reducing costs. It is.

  Among the composite enameled wires, especially enameled wires called heat-resistant self-lubricating wires with good sliding properties have a heat resistance of 155 to 180 ° C. or more, use polyesterimide for the inner layer, and self-lubricating polyamide or the like for the outermost layer. Many use self-lubricating polyamideimide. This heat-resistant self-lubricating wire is widely used as a winding for heat-resistant motors, electrical motors, transformers and the like because of its good balance between characteristics and cost.

  On the other hand, in the field of industrial motors used in electrical equipment, motor drive power supplies are being converted to inverters in order to reduce energy consumption. For this reason, enameled wires are required to have excellent high-frequency characteristics, particularly inverter surge resistance (increasing the life of inverter surge charging).

  In addition, the production of stator coils using a concentrated winding method that reduces the copper loss by reducing the amount of enameled wire used to increase the efficiency of the motor is also in progress. In the concentrated winding method, the enameled wire is aligned and wound on the stator while applying a high tension. Therefore, the enameled wire is more easily damaged than the general inserter winding method. For this reason, the enameled wire used in the concentrated winding method is required to be improved in adhesion and flexibility.

  The prior art document information related to the invention of this application includes the following.

JP-A-8-138448 JP-A-2002-358835 JP-A-2002-358834

  However, it has been found that current heat-resistant self-lubricating wires have a relatively short life when used under an inverter drive power supply. In other words, heat-resistant self-lubricating wires combining polyester imide and polyamide or polyamide imide have good mechanical properties and heat resistance, but it has been found that the motor used in inverter drive power supply has an unexpectedly short life. ing.

  In addition, in the case of a stator coil wound with enameled wire being stretched at a high rate, as in the concentrated winding method, if the current heat-resistant self-lubricating wire is used, the adhesion and flexibility are low, so there is a crack in the film. It has been found that there is a concern about deterioration of electrical characteristics as a motor.

  Accordingly, an object of the present invention is to provide a heat-resistant composite enameled wire excellent in high-frequency characteristics, in particular, inverter surge resistance and coil winding property under high elongation.

  The present invention was devised to achieve the above object, and the invention of claim 1 is characterized in that a polyester layer or a heat-resistant polyester layer is formed on the outer periphery of the conductor, and the polyester imide is formed on the outer periphery of the polyester layer or the heat-resistant polyester layer. This is a composite enameled wire in which a layer is formed and a self-lubricating polyamide layer is formed on the outer periphery of the polyesterimide layer.

  In the invention of claim 2, the thickness of the polyester layer or the heat resistant polyester layer is 10 to 50% of the total thickness of the thickness of the polyester layer or the heat resistant polyester layer and the thickness of the polyester imide layer. The composite enameled wire according to Item 1.

  According to a third aspect of the present invention, in the self-lubricating polyamide layer, polyamides such as 6 nylon, 6,6 nylon, 6,10 nylon, 11 nylon, and 12 nylon are dissolved in an organic solvent, and the polyamide is dissolved in the organic solvent. The composite enameled wire according to claim 1 or 2, wherein the composite enameled wire is formed by applying and baking a paint containing a polyolefin wax or a fatty acid ester wax.

  According to the present invention, the following excellent effects are exhibited.

  (1) It has excellent high frequency characteristics, in particular, inverter surge resistance, adhesion, and flexibility, and can improve the reliability of various motors using an inverter drive power supply.

  (2) Further, it is excellent in coil winding property at high elongation, and can be applied to a coil winding method (for example, concentrated winding method) that is severely deteriorated in processing, which is industrially useful.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view of a composite enameled wire showing a preferred embodiment of the present invention.

  As shown in FIG. 1, a composite enameled wire 1 according to the present embodiment forms a polyester (resin coating film) layer (or heat-resistant polyester (resin coating film) layer) 3 on the outer periphery of a conductor 2, and the polyester layer A polyesterimide (resin coating film) layer 4 is formed on the outer periphery of the (or heat resistant polyester layer) 3, and a self-lubricating polyamide (resin coating film) layer 5 is formed on the outer periphery of the polyesterimide layer 4. These polyester layer 3, polyesterimide layer 4, and self-lubricating polyamide layer 5 are also called films.

  The polyester layer 3 is formed by, for example, dissolving a polyester resin obtained by reacting a polybasic acid component mainly composed of terephthalic acid and the like with a polyhydric alcohol component composed of ethylene glycol, glycerin, etc. (Polyester enamel wire paint), and this polyester resin enamel paint is applied to the outer periphery of the conductor 2 and baked.

  Instead of this polyester layer 3, a heat resistant polyester layer 3 may be used. The heat-resistant polyester layer 3 is made of a heat-resistant polyester resin enamel paint (heat-resistant polyester enamel wire paint) in the same manner as the polyester resin enamel paint except that tris-2-hydroxyisocyanurate is used as the polyhydric alcohol component. A polyester resin enamel paint is applied to the outer periphery of the conductor 2 and baked.

  The polyesterimide layer 4 is, for example, a heat-resistant polyesterimide formed by reacting a polybasic acid component mainly composed of terephthalic acid and imide acid and a polyhydric alcohol component composed of ethylene glycol, tris-2-hydroxydiisocyanurate, or the like. The resin is dissolved in an organic solvent to form a heat-resistant polyesterimide resin enamel paint (polyesterimide enamel wire paint), and this heat-resistant polyesterimide resin enamel paint is applied to the outer periphery of the polyester layer 3 and baked.

  However, the thickness d3 of the polyester layer (or heat-resistant polyester layer) 3 is the total thickness (hereinafter referred to as (d3 + d4) of the thickness d3 of the polyester layer (or heat-resistant polyester layer) 3 and the thickness d4 of the polyesterimide layer 4. )) To 10-50%. This is because if the thickness d3 of the polyester layer (or heat-resistant polyester layer) 3 is less than 10% of (d3 + d4), there is little improvement effect of high-frequency characteristics, particularly inverter surge resistance, adhesion, and flexibility. is there. Further, when the thickness d3 of the polyester layer (or heat-resistant polyester layer) 3 exceeds 50% of (d3 + d4), the heat resistance tends to decrease.

  That is, the composite enameled wire 1 has a thickness d3 of the polyester layer (or heat-resistant polyester layer) 3 of 10 to 50% of (d3 + d4), so that it has been difficult so far while maintaining the properties as a heat-resistant enameled wire. It is characterized by improved and improved high frequency characteristics, adhesion and flexibility.

  The self-lubricating polyamide layer 5 is made of, for example, a polyamide resin such as 6 nylon, 6,6 nylon, 6,10 nylon, 11 nylon or 12 nylon dissolved in an organic solvent, and a polyolefin wax in the organic solvent in which the polyamide resin is dissolved. And a suitable amount of a fatty acid ester wax is blended to form a self-lubricating polyamide resin enamel paint (self-lubricating polyamide enamel wire paint).

  The thickness of the self-lubricating polyamide layer 5 is not particularly limited. This is because the thickness of the self-lubricating polyamide layer 5 can be freely changed in accordance with the use and purpose of the composite enameled wire 1.

(Example 1)
First, a polyester enameled wire paint obtained by a general manufacturing method was applied and baked on the outer periphery of a copper wire as the conductor 2 having a conductor diameter of φ1.0 mm to form a polyester layer 3 having a thickness of 0.004 mm. Next, a polyesterimide enamel wire paint obtained by a general production method was applied to the outer periphery of the polyester layer 3 and baked to form a polyesterimide layer 4 having a thickness of 0.026 mm. Further, a self-lubricating polyamide enamel wire paint obtained by a general manufacturing method is applied to the outer periphery of the polyesterimide layer 4 and baked to form a self-lubricating polyamide layer 5 having a thickness of 0.002 mm. Got. The thickness d3 of the polyester layer 3 is about 13.3% of (d3 + d4). However, the film thickness was measured based on JIS C 3003.

(Example 2)
A composite enameled wire 1 was obtained in the same manner as in Example 1 except that the thickness of the polyester layer 3 was 0.010 mm and the thickness of the polyesterimide layer 4 was 0.020 mm. The thickness d3 of the polyester layer 3 is about 33.3% of (d3 + d4).

(Example 3)
A composite enameled wire 1 was obtained in the same manner as in Example 1 except that the thickness of the polyester layer 3 was 0.014 mm and the thickness of the polyesterimide layer 4 was 0.016 mm. The thickness d3 of the polyester layer 3 is about 46.7% of (d3 + d4).

Example 4
A heat-resistant polyester enamel wire paint obtained by a general manufacturing method is applied and baked on the outer periphery of a copper wire having a conductor diameter of φ1.0 mm instead of the polyester layer 3 to form a heat-resistant polyester layer 3 having a thickness of 0.010 mm. Formed. A composite enameled wire 1 was obtained in the same manner as in Example 1 except that the polyesterimide layer 4 having a thickness of 0.020 mm was formed on the outer periphery of the heat-resistant polyester layer 3. The thickness d3 of the heat resistant polyester layer is about 33.3% of the total thickness (d3 + d4) of the thickness d3 of the heat resistant polyester layer and the thickness d4 of the polyesterimide layer.

(Comparative Example 1)
A polyesterimide layer 4 having a thickness of 0.030 mm was directly formed on the outer periphery of a copper wire having a conductor diameter of 1.0 mm. Thereafter, a composite enameled wire was obtained in the same manner as in Example 1. The composite enameled wire of Comparative Example 1 is a typical current heat-resistant self-lubricating wire.

(Comparative Example 2)
A composite enameled wire was obtained in the same manner as in Example 1 except that the thickness of the polyester layer 3 was 0.002 mm and the thickness of the polyesterimide layer 4 was 0.028 mm. The thickness d3 of the polyester layer 3 is about 6.67% of (d3 + d4).

(Comparative Example 3)
A composite enameled wire was obtained in the same manner as in Example 1 except that the thickness of the polyester layer 3 was 0.016 mm and the thickness of the polyesterimide layer 4 was 0.014 mm. The thickness d3 of the polyester layer 3 is about 53.3% of (d3 + d4).

  (Characteristic test method of composite enameled wire) The following characteristic tests were performed on the composite enameled wires of Examples 1 to 4 and Comparative Examples 1 to 3 obtained in this manner.

1) Coil winding property under high elongation -Part 1-Adhesion test with conductor Each composite enameled wire was sampled to a length of 250 mm, then twisted according to JIS C 3003, and the number of twists to start peeling of the film was determined. Determined (peel method).

2) Coil winding property under high elongation -Part 2-Winding test after 20% elongation First, each composite enameled wire was stretched by 20%. Next, the 20% stretched composite enamel wire was wound around a winding rod 1 to 10 times the conductor diameter, and the presence or absence of cracks in the coating was observed. The results are shown by the minimum winding diameter (d) at which no cracks are observed in the coating.

3) Dielectric breakdown voltage test For each composite enameled wire, a two-stranded sample was prepared based on JIS C 3003, and the dielectric breakdown voltage (kV) of the two-stranded sample was measured.

4) Inverter surge resistance Two twisted samples were prepared based on JIS C 3003, and the electric life (time) of a 400 V class inverter (maximum peak value 1.8 kVp-p) was measured for the two twisted samples.

5) Heat-resistant deterioration First, for each composite enameled wire, a two-stranded sample was prepared based on JIS C 3003, and the two-stranded sample was heated at 240 ° C. for 7 days. Next, the dielectric breakdown voltage of the two-stranded sample after heating was measured. Finally, the dielectric breakdown voltage residual ratio (%) was obtained by comparing this dielectric breakdown voltage with the initial value of the dielectric breakdown voltage obtained in 3), and the superiority or inferiority of the heat deterioration resistance was evaluated.

  In Table 1, the structure of each composite enamel wire of Examples 1-4 and Comparative Examples 1-3 and the characteristic test result are shown.

  As shown in Table 1, each of the composite enamel wires 1 of Examples 1 to 3 has a polyester layer 3 formed on the outer periphery of the conductor 2 and has a thickness d3 of 10 to 50% of (d3 + d4). The applied life is 188,486,621 hours, which is excellent in inverter surge resistance, adhesiveness is excellent as 80,84,86 times, and flexibility is excellent as 1-2d, 1d, 1d. In addition, the dielectric breakdown voltage residual ratio is 78, 65, 58%, which is excellent in heat resistance deterioration, and the dielectric breakdown voltage is as high as 12.2, 12.1, 12.4 kV. Therefore, each composite enameled wire 1 of Examples 1 to 3 is a heat-resistant enameled wire with a very good balance.

  In the composite enameled wire of Example 4, the heat-resistant polyester layer 3 is formed on the outer periphery of the conductor 2 and the thickness d3 is 10 to 50% of (d3 + d4). Excellent in adhesion, excellent in adhesion as 82 times, and flexible in 1-2d. Moreover, the dielectric breakdown voltage residual ratio is 88%, which is excellent in heat deterioration resistance, and the dielectric breakdown voltage is as high as 12.3 kV. Therefore, the composite enameled wire of Example 4 is also a heat balanced enameled wire with a very good balance.

  Each composite enamel wire of Examples 1 to 4 is not described in Table 1, but has excellent mechanical properties.

  Moreover, in the example of Table 1, the thickness of the self-lubricating polyamide layer 5 is as very thin as 0.002 mm. Therefore, when the outermost layer is the self-lubricating polyamide layer 5, the composite enameled wire can be reduced in diameter, which leads to cost reduction, reduction in the number of coil turns, and miniaturization of the coil. On the other hand, when a polyamideimide layer is used in place of the self-lubricating polyamide layer 5, unless the thickness is 0.005 mm, the characteristics equivalent to the inverter surge charging life shown in Table 1 cannot be obtained. That is, since each composite enameled wire of Examples 1 to 4 has the self-lubricating polyamide layer 5 as the outermost layer, even if the thickness is about 40% as compared with the case where the outermost layer is a polyamideimide layer, the same characteristics are obtained. Have

  In other words, the use of the self-lubricating polyamide layer 5 has the advantage that the mechanical properties and heat resistance of the composite enameled wire 1 are improved. On the other hand, if a polyamideimide layer is used in place of the self-lubricating polyamide layer 5, (i) the coating thickness must be increased, resulting in a large coil shape. (Ii) The number of coatings increases during enamel wire production. Therefore, there is a disadvantage that the production efficiency is lowered.

  In contrast, the composite enameled wire of Comparative Example 1 represented by the current heat-resistant self-lubricating wire has excellent breakdown resistance with a dielectric breakdown voltage residual ratio of 83%, but the polyester layer (or heat-resistant polyester layer) 3 Is not provided, the life of electricity due to inverter surge is as short as 120 hours. Moreover, both adhesiveness (72 times) and flexibility (2-3d) are inferior to Examples 1-4.

  Since the composite enameled wire of Comparative Example 2 has the polyester layer 3 formed, the dielectric breakdown voltage residual ratio is 80% and the heat deterioration resistance is excellent, but the thickness d3 of the polyester layer 3 is (d3 + d4). Since it is about 6.67% and less than 10%, there is little improvement effect of the charging life (124 hours), adhesion (76 times), and flexibility (2-3d) due to inverter surge.

  In the composite enameled wire of Comparative Example 3, the thickness d3 of the polyester layer 3 is about 53.3% of (d3 + d4), which exceeds 50%, and the polyester layer 3 is thick. Time), adhesion (87 times), and flexibility (1d) are excellent, but heat deterioration (51%) is inferior to Examples 1-4.

  Thus, since the thickness d3 of the polyester layer (or heat resistant polyester layer) 3 is 10 to 50% of (d3 + d4), the composite enameled wire 1 according to the present embodiment maintains the characteristics as a heat resistant enameled wire. It is excellent in high frequency characteristics, especially inverter surge resistance, adhesion, and flexibility, and can improve the reliability of various motors using inverter drive power supply.

  In addition, the composite enameled wire 1 is excellent in flexibility, so it has excellent coil winding performance at high elongation and can be applied to coil winding methods (for example, concentrated winding method) that are severely deteriorated in processing. Yes, industrially useful.

It is a cross-sectional view of a composite enameled wire showing a preferred embodiment of the present invention.

Explanation of symbols

1 Composite enameled wire 2 Conductor 3 Polyester layer 4 Polyesterimide layer 5 Self-lubricating polyamide layer

Claims (3)

  A polyester layer or a heat-resistant polyester layer is formed on the outer periphery of the conductor, a polyesterimide layer is formed on the outer periphery of the polyester layer or the heat-resistant polyester layer, and a self-lubricating polyamide layer is formed on the outer periphery of the polyesterimide layer. Composite enameled wire.   The composite enameled wire according to claim 1, wherein the thickness of the polyester layer or the heat-resistant polyester layer is 10 to 50% of the total thickness of the thickness of the polyester layer or the heat-resistant polyester layer and the thickness of the polyesterimide layer. . The self-lubricating polyamide layer is prepared by dissolving polyamide such as 6 nylon, 6,6 nylon, 6,10 nylon, 11 nylon and 12 nylon in an organic solvent, and polyolefin wax or fatty acid ester type in the organic solvent in which the polyamide is dissolved. The composite enameled wire according to claim 1 or 2, which is formed by applying and baking a paint containing a wax.

Images