JPH04264308A - Self-lubrication enamel wire - Google Patents

Abstract

PURPOSE:To obtain a self-lubrication enamel wire which is excellent in slippage and wear resistance, good for adhesion to coil varnish and sound in appearance by improving the composition of application material for better mechanical wiring property than that of a conventional insulated wire. CONSTITUTION:An enamel wire is manufactured by applying and firing paint, which is made by adding and mixing 0.5-10 pts.wt. fatty acid polyester resin with a melting point of 40-90 deg.C and the number of carbons being 15 or more to/with 100 pts.wt. polyamideimide resin, directly or via other insulator. It is thus possible to obtain a self-lubrication enamel wire which is excellent in mechanical wiring property, good for adhesion to coil varnish and sound in appearance.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-lubricating enameled wire (hereinafter referred to as enameled wire), and more particularly to an improved enameled wire that has excellent mechanical windability and adhesion to coil varnish.

0002

BACKGROUND OF THE INVENTION In recent years, there has been a demand for the development of enamelled wires with excellent mechanical windability for the purpose of downsizing electrical equipment, speeding up coil winding operations, and reducing coil failure rates. To improve machine windability, make the finished outer diameter of the wire thinner,
Ideas include increasing flexibility, increasing the mechanical strength of the coating, and imparting slipperiness to the enameled wire (self-lubricating).

Conventionally, one method of increasing the strength of the enameled wire coating has been to bake nylon or polyamide-imide resin onto the upper layer of the enamel wire coating. (Japanese Unexamined Patent Publication No. 61-26949).

[0004] In particular, the upper layer baking of polyamide-imide resin is superior to nylon in its heat resistance, so polyester wire (classes B to F) and polyesterimide wire (class F) are used.
, polyesterimide wire (H type), etc., and are widely used as amide-imide overcoated polyester wire and amide-imide overcoated H type polyesterimide wire, respectively.

However, as coil winding work has recently become more demanding, it has become necessary to provide these wires with slipperiness to further improve coil winding properties.

[0006]

[Problem to be Solved by the Invention] For this reason, the surface of the enameled wire is coated with lubricating properties such as solid paraffin, beeswax, carnauba wax, etc. to impart slipperiness and improve the windability to some extent. However, it is still not enough. Therefore, some methods have been used to bake a polyamide-imide paint containing a low molecular weight polyolefin (low molecular weight polyethylene, low molecular weight polypropylene). This improves slipperiness and abrasion resistance, which also improves mechanical windability. However, there was a problem in that the adhesion with the coil varnish was reduced, and the fields of application were limited in equipment that performed coil varnish treatment.

An object of the present invention is to eliminate the drawbacks of the prior art described above, and to provide excellent mechanical winding properties and adhesion to coil varnish. The purpose is to provide an enameled wire that is also sound in appearance.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the self-lubricating enameled wire of the present invention has a structure in which a melting point of 40% is applied to 100 parts by weight of polyamideimide resin on a conductor.
- 90 ° C. and mixed with 0.5 to 10 parts by weight of a fatty acid polyester resin having 15 or more carbon atoms,
The coating is applied directly or through another insulating material and baked.

[0009]

[Function] When low molecular weight polyolefin (low molecular weight polyethylene resin, low molecular weight polypropylene resin) is added to polyamide-imide resin, the adhesion with coil varnish is reduced. When the cause of this is investigated, for example, the melting point of low molecular weight polyethylene is 107°C, and the melting point of low molecular weight polypropylene is 150°C. Since this is equivalent to the coil varnish treatment temperature, the above-mentioned lubricant is not sufficiently melted due to the curing heat during treatment, resulting in a decrease in wettability with the coil varnish and a decrease in adhesiveness.

Therefore, in the present invention, a fatty acid polyester resin having a low melting point is added.

However, if the melting point is 40° C. or lower, the melting point will be 30° C. or higher during use in the summer after manufacturing the enamelled wire, which is disadvantageous because the wire will tend to stick. Also, the melting point is 90℃
In the above, the adhesion with the coil varnish decreases due to the above-mentioned reason, that is, the optimum melting point is 40 to 90°C.

[0012] Regarding the number of carbon atoms in the fatty acid polyester resin, as a result of investigation, it was found that if the number of carbon atoms is less than 15, it does not provide sufficient slipperiness.

Regarding the amount of fatty acid polyester resin added, experimental results show that if it is less than 0.5 parts by weight, the slip properties are insufficient, and if it is more than 10 parts by weight, the appearance of the electric wire will be noticeably rough and the product value will be reduced. . Therefore, 0.5-1
0 parts by weight was added.

[0014] This fatty acid polyester resin may be simply added, but from the viewpoint of storage stability of the paint,
It is preferable to react with the polyamide-imide resin at a temperature of about 00 to 200°C for about 1 to 20 hours.

[0015]

[Examples] Examples and comparative examples of the present invention will be explained below using Table 1.

In the present example and comparative example, the conductor diameter of the electric wire was 1.0 mmφ, and the film thickness was 45 μm. is a film thickness of 3 to 4 μm
The test material was baked to give the following properties. Coil varnish is
Solvent-type epoxy varnish (manufactured by Hitachi Chemical Co., Ltd., WF-291
) was used. The adhesion test was conducted in accordance with NEMA-MW-1000, and a helical coil with an inner diameter of 6.3 mm and a length of 70 mm was coated with coil varnish twice (the first time was at 130°C for 1 h,
The second time was carried out at 130°C for 4 hours). Further, the characteristics of the enameled wire were determined in accordance with JISC3003.

Table 1 shows the compositions and properties of Examples and Comparative Examples of the present invention.

[0018]

[Table 1]

In the following Examples and Comparative Examples, the amount of polyamideimide resin was all 100 parts by weight.

[Comparative Example 1] Polyamideimide resin 100
Paint is applied and baked based on parts by weight only.

[Comparative Example 2] Polyamideimide resin 100
Based on parts by weight, low molecular weight polyethylene (melting point 107°C
) 1 part by weight was added and baked.

[Comparative Example 3] Polyamideimide resin 100
Low molecular weight polypropylene (melting point 150
℃) 1 part by weight was added and baked.

[Example 1] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
℃) 0.5 parts by weight was added and baked.

[Example 2] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
℃) 1 part by weight was added and baked.

[Example 3] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
℃) 3 parts by weight was added and baked.

[Example 4] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
℃) 5 parts by weight was added and baked.

[Example 5] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
C) 10 parts by weight was added and baked.

[Example 6] Polyamideimide resin 100
Fatty acid polyester resin A (melting point 60
C) 15 parts by weight was added and baked.

[Example 7] Polyamideimide resin 100
Fatty acid polyester resin B (melting point 85
℃) 3 parts by weight was added and baked.

[Example 8] Polyamideimide resin 100
Fatty acid polyester resin B (melting point 85
℃) 5 parts by weight was added and baked.

Various characteristics of the following three comparative examples and eight working examples will be explained.

[0032] In terms of static friction coefficient, all the samples except Comparative Example 1 (0.15) were good. The reciprocating wear (number of times) was almost good except for Comparative Example 1 and Examples 5 and 6. In terms of varnish adhesion, Comparative Examples 2 and 3 were particularly poor. Visual inspection of the appearance showed that all the samples except Example 6 were good.

To summarize the above results, 0.5 to 10 parts by weight, preferably 1 to 10 parts by weight of fatty acid polyester resin (melting point 40 to 90°C) is added to 100 parts by weight of polyamideimide resin.
It has become clear that the enameled wire coated and baked with a paint containing 5 parts by weight exhibits the best properties.

[0034]

According to the present invention, fatty acid polyester resin (
The enamelled wire coated and baked with the addition of (melting point: 40 to 90°C) has excellent mechanical winding properties and also has good adhesion to coil varnish. That is, by using the paint of the present invention, work efficiency is improved and the effect of improving economic efficiency is significant.

[0035]

Claims (1)

[Claims] [Claim 1] Polyamideimide resin 10 on the conductor.
0.5 to 10 parts by weight of a fatty acid polyester resin having a melting point of 40 to 90°C and a carbon number of 15 or more
A self-lubricating enameled wire characterized in that it is made by applying and baking a paint mixed with parts by weight either directly or through another insulator.