JPH0628943U - Fireproof insulated wire - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a fireproof insulated wire having a reduced insulation thickness and improved electrical reliability. According to the present invention, a thin first refractory layer 2 composed of a glass-based tape is formed on the outer circumference of a conductor 1, and a mica or alumina-supported tape is formed on the outer circumference of the first refractory layer 2. 2 to form the refractory layer 3 and then to the second
An insulating layer 4 is formed on the outer periphery of the refractory layer 3, a second refractory layer 3 is formed to a thickness of 0.1 to 0.15 mm, and an insulating layer 4 is formed to a thickness of 0.3.
It is formed to be ~ 0.7 mm.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a fireproof insulated wire.

[0002]

[Prior art]

 As a conventional electric wire of this type, as shown in FIG. 2, it is known that a fire resistant layer 100 is formed on the outer circumference of a conductor 1 and an insulating layer 101 is formed on the outer circumference thereof. The refractory layer 100 is formed by winding a glass mica tape around the outer periphery of the conductor 1. The insulating layer 101 is formed by extrusion coating polyethylene on the refractory layer 100. When the conductor 1 had a diameter of 1.35 mm, the refractory layer 100 had a thickness of 0.25 mm, the insulating layer 101 had a thickness of 0.8 mm, and the overall diameter was 3.45 mm.

[0003]

[Problems to be solved by the device]

 The insulation thickness of the conventional fireproof insulated wire (the total thickness of the fireproof layer 100 and the insulation layer 101) was 1.05 mm, which was thick. The glass mica tape is made of glass fiber, and when the fiber was mixed or infiltrated into the polyethylene during melt extrusion of the crosslinked polyethylene, pinholes were generated, often impairing electrical reliability.

Therefore, an object of the present invention is to provide a fireproof insulated wire with a thin insulation thickness and high electrical reliability.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention forms a thin first refractory layer consisting of a glass-based tape on the outer periphery of a conductor and carries mica or alumina on the outer periphery of the first refractory layer. A second refractory layer consisting of a tape is formed, and then an insulating layer is formed on the outer periphery of the second refractory layer. The second refractory layer is formed to a thickness of 0.1 to 0.15 mm. .3 to 0.7 mm.

[0006]

[Action]

 In this invention, the insulation thickness can be reduced, and the composition of the insulation layer and the outer insulation layer also provides excellent fire resistance. Also, since there are two refractory layers, the probability of penetration of all layers of pinholes is extremely small, and electrical reliability is improved.

[0007]

【Example】

 A preferred embodiment of the present invention will be described below with reference to the drawings.

In the embodiment shown in FIG. 1, 50% by weight or more of an inorganic substance such as glass mica tape is provided on the outer periphery of the conductor 1 made of a copper conductor single wire or a copper conductor stranded wire plated with tin, nickel, silver or the like. A thin first refractory layer 2 is formed by winding a refractory tape containing the same. If the diameter of the conductor 1 is 1.35 mm, the thickness of the first refractory layer 2 is 0.05 to 0.25 mm. A second refractory layer 3 made of a tape carrying mica or alumina is formed on the outer periphery of the first refractory layer 2. The second refractory layer 3 is a mica- or alumina-supported tape, which does not contain glass fiber as a constituent material, and is not mixed with a non-woven fabric such as polyester, polyamide or paper, or a tape such as polyester, polyimide or paper. Composed of glued tape. On the outer periphery of the second refractory layer 2, for example, an insulating layer 4 made of an aromatic polymer and having a thickness of 0.3 to 0.7 mm is formed. Here, the aromatic polymer means aromatic polyamide, polyether ketone, polyether ether ketone, polybutylene terephthalate, polyphenylene sulfide, polyethylene terephthalate, polyphenylene oxide, polycarbonate, polysulfone, polyether sulfone, polyether imide, One or a blend of two or more kinds selected from polyarylate and polyimide, or a polymer alloy containing these resins as a main component, which may be crystalline or amorphous. Further, as the insulating layer 4, not only conventional polyethylene and crosslinked polyethylene but also a layer formed by tape winding or the like may be used in common with a layer extruded and molded by melt extrusion.

Note that one or more tape layers may be provided between the second refractory layer 3 and the insulating layer 4 or between the first and second refractory layers 2 and 3. Due to the presence of these tape layers, excellent electrical characteristics can be ensured even if the first insulating layer 2 is made thinner. As the tape layer, a polyamide film, a polyester film or the like having a thickness of 0.025 to 0. It is enough to wrap one piece of tape with a thickness of 05 mm.

Table 1 below shows respective configurations of various examples and comparative examples.

[0011]

[Table 1]

Table 2 shows experimental results of fire resistance and flammability of each of the examples shown in Table 1 and the comparative examples. In Table 2, ◯ means pass, and x means fail.

[0013]

[Table 2]

The test method of the fire resistance performance of Table 2 is that the test electric wire attached to the pearlite plate is attached to the test furnace that has passed the certification test of the fire and heat resistant electric wire certification operation committee, and the flame temperature curve defined in JIS A 1304 While heating for 30 minutes at the same temperature, the insulation resistance was measured for 30 minutes before and 30 minutes before heating. As a result of the withstand voltage test before heating, during heating, and immediately after heating, The measurement results of the burning distances of the cables in the existing parts were obtained respectively.

Although a glass mica tape was used as the first refractory layer 2 shown in the table, any tape mainly composed of glass may be used. In the past, sufficient fire resistance could not be obtained without increasing the thickness of the refractory layer, and if the refractory layer was thick, the fuzz of glass could pierce the polyethylene layer, causing pinholes. Even if the thickness of the first refractory layer 2 is reduced, sufficient refractory performance can be obtained, and if the first refractory layer 2 is thin, the length of fuzz of the glass is short, and the glass extends beyond the second refractory layer 3 to the insulating layer 4. No longer sticks.

[0016]

[Effect of device]

 As described above, according to this invention, the insulation thickness is thin, and the weight and size can be reduced. Also, because of the multi-layer structure, the probability of penetrating all layers of the pinhole is extremely small, and electrical reliability is improved. Since the first refractory layer is formed by the tape mainly made of glass, even if the glass fibers fluff and stick into the second refractory layer, they do not penetrate to the insulating layer. Moreover, since the first refractory layer can be made thinner than before, the fluffing of the glass can be shortened.

[Brief description of drawings]

FIG. 1 is a sectional view showing a preferred embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional example.

[Explanation of symbols]

 1 conductor 2 first refractory layer 3 second refractory layer 4 insulating layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hideo Sunazuka 1-5-1 Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (72) Isao Takahashi 1-1-5 Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (72) Inventor Masatake Hasegawa 1-9 Futaba-cho, Numazu-shi, Shizuoka Fujikura Electric Wire Co., Ltd. Numazu Plant Co., Ltd. (72) Motohisa Murayama 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Electric Line Co., Ltd. In the company

Claims (1)

[Scope of utility model registration request] 1. A thin first refractory layer (2) made of a glass-based tape is formed on the outer periphery of a conductor (1), and mica or alumina is carried on the outer periphery of the first refractory layer (2). A second refractory layer (3) made of tape is formed, an insulating layer (4) is further formed on the outer periphery of the second refractory layer (3), and the second refractory layer (3) has a thickness of 0.1 to 0. A fireproof insulated wire, which is formed to have a thickness of 15 mm and an insulating layer (4) having a thickness of 0.3 to 0.7 mm.