JP3419055B2 - Insulated wire - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated wire used at high temperatures, and more particularly to an insulated wire having an improved conductor structure.

[0002]

2. Description of the Related Art Conventionally, insulated wires used under high temperature are
A heat resistant coating is applied and baked on a conductor obtained by plating aluminum or copper with AgNi or the like to impart heat resistance. For example, in insulated wires used at 300 ° C. or higher, it is common to use a ceramic paint that can be mineralized as a heat resistant paint, but in this case, the conductor is copper plated with Ag or Ni. Aluminum is used because it has very poor adhesion to the film.
However, since the melting point of aluminum is 660 ° C., the operating temperature is limited, so that the conductor of an electric wire used at 660 ° C. or higher has relatively higher adhesion than copper plated with Ni or Ag. A wire rod in which stainless steel, which is a good and high heat resistant material, is clad around copper has been experimentally used.

[0003]

By the way, among the commonly used conductors in which a stainless layer is clad on copper, in particular, in the case of a single wire having a diameter of about 0.7 mm, the cross-sectional area ratio is 0.96 stainless steel layer to copper
It is very difficult to process below. Therefore, the stainless steel layer having a hardness higher than that of copper increases and becomes hard, and it is difficult to apply, for example, to a conductor of an electric wire that is shaped into a predetermined shape after processing such as a movable electric wire. Moreover, the adhesion to the ceramic paint was not as good as that of a conductor made of aluminum or copper.

Therefore, the present invention has been devised to effectively solve the above problems, and an object thereof is to provide a novel insulated wire with greatly improved processability and adhesion to a heat-resistant paint. It is provided.

[0005]

To accomplish the above object means to provide a process, the stainless steel layer on the conductor formed by cladding the periphery of the copper wire, the insulated wire made by baking coating a heat-resistant coating, the conductor Is baked at a temperature of 700-1100 ° C
Is obtained by blunt, the stainless layer are those Vickers hardness (Hv) was 200 or less.

In the present invention, the reason why the Vickers hardness (Hv) of the stainless steel layer is limited to 200 or less is as follows.
This is because workability such as bending is poor.

Further, the annealing temperature of the conductor is set to 700 to 1100.
As shown in FIG. 1, in general, a conductor in which a stainless steel layer is clad with copper shows a change in hardness around an annealing temperature of 700 ° C. Therefore, the effect of annealing can be expected at a temperature lower than this. This is because the stainless steel layer is melted at 1100 ° C. or higher.

[0008]

As described above, according to the present invention, since the Vickers hardness (Hv) of the stainless steel layer is 200 or less, workability such as bending is improved. Further, the annealing temperature of the conductor is 700 to
By setting the temperature in the range of 1100 ° C., impurities and segregation existing on the stainless steel surface are diffused, so that the adhesion between the conductor and the ceramic coating is improved.

[0009]

EXAMPLES Examples of the present invention will be described in detail below.

First, as shown in FIG. 2, a non-oxidized copper rod is used as a core material 1, and this is made into a pipe 2 made of SUS304 alloy.
Conductor 3 having an outer diameter of 0.7 mm in a state in which the pipe, which is the conductor part, and the core material are in close contact with each other
Was formed. The thickness of the SUS304 alloy layer 2 of this conductor was 100 μm, and the cross-sectional area ratio to the copper wire was 0.9.
It was 6. After that, the conductor 3 was wound around a stainless bobbin for 500 m, placed in a high temperature electric furnace, and annealed by heat treatment for 1 hour in a nitrogen atmosphere.

Next, the materials shown in Table 1 were stirred for 3 hours to produce a heat-resistant paint 4, which was placed on the conductor 3 using a vertical baking machine with a furnace length of 7.2 m, at a baking temperature. 400 ° C,
After forming the insulated electric wire 5 by coating and baking 6 times at a linear speed of 5 m / min, the Vickers hardness (H
v) The test and the adhesion evaluation of the insulator were performed. For the Vickers hardness (Hv) test, a micro hardness tester with a diamond pyramid (apex angle 136 ° ± 30 ') was used as the indenting material, and those with Hv200 or less passed, and 200 or more failed. And In addition, the evaluation of the adhesiveness of the insulator of the insulated wire was performed by winding it around a mandrel in 1φ increments from 1 to 30φ, and the diameter before the peeling occurred was shown as 6
Values less than or equal to φ were regarded as acceptable.

(Example 1) Silicon oxide 4 as a resin
A heat-resistant coating consisting of 0 wt% and polycarbosilane 10 wt%, Al ₂ O ₃ 10 wt% as an inorganic filler, and xylene 40 wt% as a solvent was used, and the annealing temperature of the conductor was 700 ° C.

(Example 2) 30 wt% polysilastyrene
%, Polymethylcarbosilane 20 wt%, MgO 20w
A heat-resistant paint composed of t% and xylene 30 wt% was used, and the annealing temperature of the conductor was set to 850 ° C.

(Example 3) 35 wt% polyborosiloxane
%, Polycarbosilastyrene 10 wt%, mica 5 wt
%, Xylene 50 wt%, and the annealing temperature of the conductor was set to 1100 ° C.

Comparative Example 1 A heat-resistant paint having the same composition as in Example 1 was used, and annealing of the conductor was omitted.

(Comparative Example 2) A heat-resistant paint having the same composition as in Example 1 was used, and the annealing temperature of the conductor was set to 600 ° C.

(Comparative Example 3) The annealing temperature of the conductor is 1200 ° C.
And

[0018]

[Table 1]

As a result, as is clear from Table 1, all the electric wires of Examples 1 to 3 have an adhesion with the insulator of 5 or less, and the Vickers hardness (Hv) of the stainless steel layer is 200 or less. And passed. On the other hand, in Comparative Example 1 in which the annealing of the conductor was omitted and Comparative Example 2 in which the annealing temperature was 700 ° C. or less, neither the adhesion to the film nor the Vickers hardness (Hv) of the stainless layer was rejected, Further, in Comparative Example 3 in which the annealing temperature was 1100 ° C. or higher, the conductor was melted.

[0020]

In summary, according to the present invention, since the Vickers hardness (Hv) of the stainless steel layer is 200 or less, workability such as bending is improved, and the annealing temperature of the conductor is set in the range of 700 to 1100 ° C. Since it is set, impurities and segregation existing on the stainless steel surface are diffused, and an excellent effect such that the adhesion between the conductor and the ceramic coating is improved is exhibited.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the annealing temperature of stainless steel wire and Vickers hardness (Hv).

FIG. 2 is an enlarged sectional view showing an embodiment of the present invention.

[Explanation of symbols]

1 copper wire 2 stainless steel layers 3 conductors 4 Heat resistant paint 5 insulated wire

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideki Yagyu Inventor Hideki Yagyu 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Hiritsu Electric Cable Co., Ltd. (56) Reference JP-A-5-290644 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01B 7/29 H01B 5/02 H01B 7/02

Claims (2)

(57) [Claims] 1. An insulated electric wire obtained by coating and baking a heat resistant coating on a conductor obtained by clad a stainless steel layer around a copper wire, wherein the conductor has a temperature of 700 to 1100 ° C.
An insulated electric wire which is annealed and has a Vickers hardness (Hv) of 200 or less in the stainless steel layer. 2. The insulated wire according to claim 1, wherein the heat-resistant paint is a ceramic paint.