JPH0624092Y2 - Heat resistant insulated wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a heat-resistant insulated wire that can withstand a use temperature of 400 ° C. or higher.

[Conventional technology and its problems]

As a constitution of the heat-resistant insulated wire, there can be mentioned one having a glass fiber cloth as a base on the periphery of a conductor and winding a glass mica tape having a laminated mica attached thereto to form a fire resistant layer.

Further, in recent years, it has been proposed to use ceramic fibers having better fire resistance and heat resistance instead of the glass mica tape.

However, the spun or woven fabric of this ceramic fiber has fiber fluff, which causes braiding,
During horizontal thread winding work or taping work, the fluffed parts fall off and accumulate in the essential parts of each device, making it difficult to work, and fine fibers are scattered. There is a problem that it may invade the respiratory tract and damage the health.

[Purpose of device]

The present invention has been made in view of the above points, and an object thereof is to provide a heat-resistant insulated wire capable of improving workability and productivity.

[Means for achieving the purpose]

In order to achieve the above-mentioned object, in the present invention, a tape of ceramic fiber woven cloth coated with polyvinyl alcohol or a tape in which ceramic fibers are vertically aligned in a tape shape is wound around the conductor, A heat-resistant varnish coating is applied to this wound layer.

[Action]

Since the ceramic fiber tape of the heat-resistant insulated wire of the present invention configured as described above has a heat resistance characteristic of at least 1000 ° C. or higher, sufficient heat resistance characteristics can be obtained, and the ceramic fiber tape is made of polyvinyl alcohol. Since it is coated with (Povar) resin, no fluff or fine fibers are scattered.

In addition, the wrapping layer of the woven fabric tape of fiber yarn coated with polyvinyl alcohol or the tape in which the ceramic fibers are vertically aligned in a tape shape, the heat-resistant varnish smoothly penetrates into the layer, and the varnish layer is formed on the bottom surface. In some cases, it is formed, and the moisture resistance is improved.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

In the figure, 1 is 2 0.45mmφ nickel plated annealed copper wire
A conductor obtained by twisting two bundles (hereinafter referred to as a conductor), and a tape for laminating mica and glass fiber cloth, or a tape for laminating mica and phenol-formaldehyde cross-linked fiber cloth on one circumference of the conductor. (0.3 mm thickness) is wound twice with 1/2 wrap to form a core, and a ceramic long fiber tape containing alumina, boria, and silica as a main component (trade name: Nextel yarn, manufactured by 3M USA, width: 8m
m, thickness: about 0.3 mm) Povar (polyvinyl alcohol) 1-4% aqueous solution (Unitika Ltd., product code:
UPO50, but 10 to 30 parts by weight of glycerin and 100 parts by weight of Povar are added), and the tape is dried and wound in 1/2 wrap, and the taping layer (wrapping layer) 2 is covered with a silicone resin varnish. 3 is impregnated and applied,
A heat resistant insulated wire according to the present invention was obtained.

The above-mentioned silicon resin varnish 3 is impregnated by applying a heat-resistant silicone varnish (Shin-Etsu Chemical Co., Ltd., product code KR169).
To 100 parts, 2 parts of a curing catalyst (Shin-Etsu Chemical Co., Ltd., product code D-168) was added, and the viscosity was adjusted to about 2 with xylene.
After adjusting the temperature to 000 CP / 25 ° C., pass the conductor 1 with the taping layer 2 through the bath of this heat-resistant silicon varnish (immersion length 2 m) at a speed of 4 m / min, and pass through the diaphragm duct. Then, it was heated and cured at 150 ° C. for 15 minutes.

As the ceramic long fibers, those having silica as a main component (for example, trade name: Siliglass manufactured by Japan Inorganic Co., Ltd.) can be used, and the tape thereof may be woven cloth or vertically aligned tape shape.

When the concentration of Povar is set to 1 to 4%, the coating effect is not obtained when it is less than 1%, and fluffing of the ceramic long fibers occurs, while when it exceeds 4%, the viscosity of the aqueous solution becomes high, This is because coating is difficult.

The reason why 10 to 30 parts by weight of glycerin is added to the aqueous solution of Poval is to impart flexibility to the coating layer (the layer of Poval impregnated in the yarn). When the amount is less than the above range, flexibility cannot be obtained. Is because the coating layer becomes weak.

Glycerin was used to impart flexibility, but in addition to this, ethylene glycol, triethylene glycol, polyethylene glycol, ethanolamine, etc. can be used. Is selected.

When this heat-resistant insulated wire was held in a furnace at 1000 ° C. and the insulating layer (taping layer 2) was observed, no abnormalities were found in the insulating layer, and it could withstand normal handling of insulated wires. There were no fluffs, no scattering of ceramic fibers during taping work, and no clogging of the guide part of the tape.

In addition, as a comparative example, an insulated wire in which a ceramic fiber tape not subjected to the coating treatment with Povar was wrapped around a heat resistant varnish was obtained in the same manner as above. From the heat-resistant insulated wires of this comparative example and the above-mentioned example, a sample having a length of 20 cm and 5 pieces was taken at equal intervals, and the taping layer (wrapping layer) 2 was cut in the length direction of the wire and a heat-resistant varnish was often formed on the inner surface. When visually observing whether or not it has permeated, those of the examples fully permeate to the inner surface,
While the varnish layer was formed on the surface of the core (the surface of the winding layer of the tape 4), it was found that the comparative example had insufficient penetration of the varnish. It can be understood that the examples have excellent moisture resistance, and the moisture resistance leads to improvement in insulation.

In the above embodiment, the winding layer of the bonding tape 4 was provided on the circumference of the conductor. However, without providing the winding layer, the ceramic long fiber tape of Poval coating was directly taped on the circumference of the conductor, and then, Silicone resin varnish coating can also be applied.

[Effect of device]

Since the present invention is configured as described above, sufficient heat resistance can be obtained, and workability and productivity can be improved without deteriorating the work environment due to fluffing and the like.

Further, since it has improved moisture resistance, it can be said to be a heat-resistant insulated wire having excellent insulation properties.

[Brief description of drawings]

The drawing is a partial perspective view of an embodiment of a heat-resistant insulated wire according to the present invention. 1 ... Conductor, 2 ... Tape winding layer (taping layer), 3 ... Heat-resistant varnish (silicon resin varnish), 4 ... Laminating tape.

Claims (2)

[Scope of utility model registration request] 1. A tape of ceramic fiber woven cloth coated with polyvinyl alcohol or a tape in which ceramic fibers are vertically aligned in a tape shape is wound around the conductor circumference, and a heat resistant varnish coating is applied to the winding layer. A heat resistant insulated wire characterized by the following. 2. The utility model registration claim (1), wherein a laminated tape of mica and glass fiber cloth or a laminated tape of mica and phenol formaldehyde cross-linked fiber cloth is provided on the conductor periphery. A heat-resistant insulated electric wire, comprising: