JP3073272B2 - Manufacturing method of glass fiber coated electric wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to manufacture electric wires for wiring and windings which require heat resistance, fire resistance and corrosion resistance and have high dielectric breakdown voltage characteristics which can be used even in an ultra-high vacuum and radiation exposure environment. It is about the method.

[0002]

2. Description of the Related Art Heat-resistant electric wires are coated with polyimide or fluororesin having excellent heat resistance, or taped with a glass mica tape, and then insulated with an insulating material such as polyethylene or polyvinyl chloride. One coated with a sheath can be mentioned.

However, electric wires using an organic material as a coating material have a high heat-resistant temperature of as low as 300 ° C., a large amount of gas generated by decomposition of the organic material, and release of absorbed and occluded gas, and high vacuum and ultra-high vacuum. It cannot be used in an environment.
In addition, it is technically difficult to wind a glass mica tape around a conductor having a diameter of 1 mm or less.
An electric wire with a wire diameter smaller than the diameter could not be manufactured. Furthermore, it is conceivable to use the sheath of the electric wire taped by this method without coating it with an organic insulating material.In this case, gas release from the organic material is not a problem, but the tape is likely to be displaced by bending etc. ,
There has been a problem that the conductor is easily exposed to the outside and insulation failure is likely to occur.

[0004] For this reason, insulation is considered by using an inorganic material. Conventionally, an electric wire of a type in which a ceramic or glass insulator tube (bead) is passed through a conductor has been used. However, in this system, a coil is wound around a coil. It is difficult to bend with a small radius of curvature, and there is a problem that the gas penetrates from the joint of the insulator tube, and the conductor is corroded. Therefore, insulating ceramic-coated electric wires are being studied.
A wet method such as a method using a dry process by VD or the like, a method using an anodic oxidation method or a method using an anodic spark discharge method has been studied.

[0005] However, in the case of a coated wire formed by a dry process or an anodic oxidation method, the coating is inferior in flexibility and adhesion, so that there is a problem that the coating is easily peeled off by bending and the dielectric breakdown voltage is low. On the other hand, electric wires produced by the anodic spark discharge method are excellent in gas release characteristics, corrosion resistance, flexibility, etc., but cannot be said to have a sufficient dielectric breakdown voltage, and similarly to the anodic oxidation method, the base (conductor) is made of metal such as Al. There was a problem of being limited.

[0006]

SUMMARY OF THE INVENTION The present invention has a coating having a high dielectric breakdown voltage, a small outgassing, a coating usable under a high vacuum, no exposure of a conductor due to bending or the like, and a coating termination treatment. An object of the present invention is to provide a method of manufacturing an unnecessary electric wire having excellent handleability.

[0007]

According to the present invention, a glass fiber is densely wound on a conductor such as a metal by a Japanese braid technique, and furthermore, an organic substance attached to the glass fiber is completely removed by washing and baking. This is based on the finding that the above-mentioned problems can be solved more efficiently, and furthermore, by impregnating with an inorganic paint, it is possible to prevent the glass fibers from fraying from the end at the time of cutting the electric wire, and the handling becomes easier. This is based on the finding that the insulating property is also improved.

That is, the present invention provides a method for producing a glass fiber-coated electric wire, which comprises washing and baking after winding a glass fiber around a conductor. Examples of the type of glass constituting the glass fiber used in the present invention include E-glass, C-glass, D-glass, T-glass, and the like, and ceramic fibers such as high-silica fiber and alumina fiber used for ordinary glass fiber. .

The diameter of the single fiber used is 3 to 9 μm.
It is preferable to select the optimum diameter together with the diameter of the conductor to be wound. When the diameter of the conductor is 1 mmφ, it is 6 to 9 μm, and when the diameter of the conductor is 0.5 mmφ, 3 to 6 μm, and further, 0.3 mmφ. Then, it is preferable to use a glass fiber having a diameter of 5 μm φ or less. The thickness of the yarn is selected depending on the diameter of the conductor.
den).

[0010] As the conductor forming the core of the electric wire,
Metals such as stainless steel, nickel, and titanium can be used in addition to metals used as ordinary metal conductors, such as copper, copper alloys, aluminum, and aluminum alloys. Note that non-metallic materials can be used as long as they are conductors. As the conductor, it is preferable to use a ceramic electric wire whose outside is covered with a ceramic film. Examples of such an electric wire include an electric wire coated with ceramics by anodization and spark discharge, an electric wire coated by a dry process such as CVD and PVD, and an electric wire coated with ceramics by hydrolysis of alkoxide and the like. .
According to such a ceramic wire, corrosion resistance and the like can be imparted depending on the properties of the ceramic film. The diameter of the conductor serving as the core of such a ceramic wire can be 1 mmφ or less, but it can be from 0.3 mmφ to a maximum of 3 mmφ. The thickness of the ceramic coating is
Those having a thickness of 1 to 20 μm are preferred. As the method and composition of forming the ceramic film, for example, those described in JP-B-58-17278 and JP-A-3-94077 can be used.

In the present invention, the outside of the conductor is braided with glass fiber and braided to cover. Of these, it is preferable to braid by braiding technology from ancient times in Japan, and braids are made with four sets, three sets, square eight sets, round eight sets, etc. It is better to do it in a winding style. At this time, it is preferable to select a method of sufficiently covering and hiding the conductor.

[0012] The thickness of the glass fiber can be arbitrarily set, but is preferably 50 to 150 µm. In the present invention, washing is performed after winding the net, and the washing is performed to remove foreign substances (organic substances) attached to glass fibers and conductors. Organic substances such as starch, polyvinyl alcohol, polyvinyl acetate emulsion, and cation activator are attached to the glass fiber as a sizing agent, and its main purpose is to remove it. Usually, since water-soluble starch is often used, washing with water may be sufficient.

However, in some cases, a water-insoluble organic substance such as an epoxy resin is used as the sizing agent. In this case, washing with an organic solvent or the like is preferably performed. When performing water washing, it is preferable to use pure water having a water quality (conductivity of 0.2 ms / cm or less) higher than that of ion-exchanged water to prevent re-contamination by impurities. At this time, it is preferable that stirring is sufficiently performed, and if heating (50 to 90 ° C.), the washing efficiency is increased.
It is preferable that the washing be carried out more sufficiently by washing in multiple stages that can always be washed with clean water than in one-stage batch washing.

By the baking performed after the washing, the remaining deposits (moisture, organic substances, etc.) can be evaporated and evaporated.
The drying is preferably performed at a temperature higher than a normal drying temperature (around 100 ° C.), and is preferably performed at 200 to 300 ° C. 300 ℃
This is because the heating strength of the glass fiber is remarkably reduced in the above, and it is difficult to sufficiently volatilize organic substances at a low temperature. If the baking time is short, the residue does not volatilize sufficiently, and if the baking time is long, it causes a decrease in strength.
6 hours is recommended. The baking atmosphere can be usually in the air, but is preferably performed in a vacuum or an inert gas. According to the above steps, it is possible to manufacture an electric wire which is excellent in degassing properties and has a high dielectric breakdown voltage and which can be used in a high vacuum or ultra-high vacuum.

Furthermore, if the inorganic coating agent is impregnated after baking, it is possible to effectively prevent fraying at the time of cutting of the electric wire and breaking of the fiber due to bending with a small radius of curvature and dust generation. As the inorganic coating agent used here, an inorganic coating agent using an organic solvent composed of a metal alkoxide and a binder from a water-soluble paint, for example, “Glaska” (trade name, manufactured by Nippon Synthetic Rubber Co., Ltd.), Daihachi Chemical Co., Ltd. "Sparsera" or the like is preferred.

The amount of impregnation is 3 to 20 g / m 2 per surface area (hereinafter referred to as apparent surface area) calculated when the cross section of the conductor after winding the glass fiber is circular.
² , 20-15 per glass fiber weight used for knitting
The range is preferably 0 mg / g. After the impregnation, it is preferable to remove the organic matter such as the organic solvent contained in the inorganic coating agent, and to heat the inorganic material in the coating agent to cure the inorganic component.

The curing temperature is lower than the softening and dissolving temperature of the conductor, and a higher temperature is desirable, but it is better to be up to 600 ° C. When the conductor is copper or a copper alloy, the temperature is preferably 500 to 600 ° C, and when the conductor is aluminum or an alloy thereof, the temperature is preferably 200 to 300 ° C. The curing time is usually preferably in the range of 10 to 60 minutes.

Further, in the case of an electric wire braided with glass fiber on a conductor having a ceramic film formed by anodic oxidation or anodic spark discharge method, a ceramic film is formed by anodic spark discharge method instead of an inorganic coating agent, It may be impregnated between glass fibers. On the other hand, at least the main component of the outermost layer is one of Al, Ti, Nb, Ta, and Mg.
A glass fiber may be wound around the seeded conductor in the same manner as described above, followed by washing and baking, and a film may be formed on the conductor by an anode spark discharge method. As a result, a ceramic film is formed on the conductor and the glass fiber is also filled with ceramic to provide corrosion resistance. Dust can be effectively prevented.

The thickness of the ceramic film to be formed is preferably 3 to 20 μm, and the total weight of the ceramic film and the impregnation amount is 5 to 40 g / m ² per apparent surface area.
Good to be. If the thickness is too small, the performance such as corrosion resistance cannot be sufficiently exhibited, and if the thickness is too large, the flexibility of the electric wire is lost. As the method and composition of forming the ceramic film, for example, those described in JP-B-58-17278 and JP-A-3-94077 can be used.

[0020]

According to the present invention, an electrical insulating layer made of glass fiber which has heat resistance and fire resistance on the surface of a metal conductor, has a high dielectric breakdown voltage, and has excellent insulating properties when wound around a coil or the like. Can be formed. Furthermore, when the aluminum wire or the aluminum clad wire according to the present invention is formed with a ceramic coating by an anode spark discharge method and then wound with glass fibers, it has heat resistance, fire resistance, and a high dielectric breakdown voltage, in addition to the characteristics of corrosion resistance. An electric wire that can be used even in an ultra-high vacuum can be manufactured.

Further, if the glass fiber-wound ceramic-coated electric wire thus obtained is wound around a coil, the insulation resistance and the breakdown voltage at the time of winding are high. can do. Furthermore, a shielded wire can be obtained by braiding a thin wire or a stranded wire, which becomes a conductor such as copper or aluminum, on this glass fiber wound wire by a similar braiding technique. [Example 1] A diameter of a conductor 1 in which carbon is clad on the outside of a copper core and aluminum is clad on the outside thereof in a two-layer structure.
The thickness of the wire is 15 μm on a 0.5 mmφ wire by the anode spark discharge method.
Was treated with a SiO ₂ ceramic coating (trade name, SI-001, Dipsol Co., Ltd.). Glass fiber 2 (fiber diameter 5 μm, count 22.5 tex: trade name, D4
50 1/2 4.4S, Unitika UM Glass Co., Ltd.). The thickness of the wound glass fiber layer was 67 μm (an enlarged schematic perspective view is shown in FIG. 1).

The wire was repeatedly washed in multiple stages while sufficiently stirring the washing liquid until the sizing agent could not be detected in the washing water by ion-exchanged water. Drying in air, 110
C. for 1 hour. Next, baking was performed at 300 ° C. in the air for 3 hours. [Example 2] An electric wire washed and baked in the same manner as in Example 1 was mixed with a hybrid paint (trade name, Glasca, M280, Nippon Synthetic Rubber Co., Ltd.) of a metal alkoxide and an inorganic filler for 1 minute with stirring. Dipped. The electric wire pulled up from the paint was rotated by a centrifugal dehydrator to adjust the amount of the paint to be impregnated, and treated so that the impregnation amount after curing was 6.7 g / m ² per apparent surface area. The curing conditions were 300 ° C. for 30 minutes.

Example 3 A glass fiber was wound on the same conductor as in Example 1 without performing the ceramic coating treatment, as in Example 1. Further, cleaning and baking were performed in the same manner as in Example 1. Thereafter, spark discharge was carried out in a solution of K ₂ O-nSiO ₂ 200 g / l using this wire as an anode and a stainless steel plate as a cathode. An 18 μm film was obtained on the conductor by spark discharge at 30 ° C., 1 A / dm ² for 10 minutes, and the impregnated ceramic and the ceramic film formed on the conductor were combined to obtain an 18 g / m ² per apparent surface area. Ceramics were formed. Comparative Example 1 An electric wire was manufactured in the same manner as in Example 1 except that cleaning and baking were not performed. Comparative Example 2 An electric wire was manufactured in the same manner as in Example 1 except that baking was not performed. [Comparative Example 3] An electric wire having a conductor diameter of 0.5 mm / φ as in Example 1 was coated with a 15 µm-thick SiO ₂ -based ceramics by an anode spark discharge method.

The performance of the obtained various electric wires is as follows.
Was evaluated. The results are shown in Table 1. Dielectric breakdown voltage measurement method "Enameled copper wire and enameled aluminum wire test method
Law ", JIS C300311, (2)" Law from two pieces "
Performed according to.Insulation resistance test method Take 5 test pieces of 30cm length from the same bobbin
Gently place the test specimen five times around a metal cylinder with a smooth surface
Wind, apply 1.96N (0.2kgf) tension to the end
While measuring the insulation resistance between the metal cylinder and the conductor.
Was. Further, the leak frequency is indicated by the number of times of conduction.Outgassing comparison test Tokyo Vacuum Co., Ltd. HUS-5GB vacuum deposition equipment
Put 10m electric wire in the chamber and exhaust by oil diffusion pump
Measure the relationship between evacuation time and pressure after the start, and
The amount of gas released from the wire due to the difference from
Were compared.Evaluation of the degree of end looseness When cutting glass fiber wound ceramic coated wire
The length at which the unraveling from the end occurred was within 1 mm was rated as ○.

[0025]

[Brief description of the drawings]

FIG. 1 is an enlarged schematic perspective view of a conductor obtained by braiding a glass fiber produced by the method of the present invention.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01B 13/00 H01B 13/06-13/08 H01B 7/02 H01B 13/22-13/26

Claims (1)

(57) [Claims] 1. The main component of at least the outermost layer is Al, Ti, Nb.
Alternatively, a method of producing a glass fiber-coated electric wire, comprising: winding a glass fiber around a conductor made of Mg; washing and baking; and then forming a ceramic film by anodic spark discharge.