JPH07282646A - Fireproof electric wire - Google Patents

Abstract

PURPOSE:To prevent the decreasing of withstanding voltage by preventing the generation of a crack in a piled part of a compound fireproof tape wound onto a conductor, eliminating the advancing of a fused object of a sheath into a conductor direction even when fused an insulator and the sheath exposed in high temperature heat and fire flame by occurrence of a fire or the like, and causing no decrease of insulation resistance as a fireproof electric wire even when the fused object of insulator and sheath is formed into a conductive carbide by incomplete combustion. CONSTITUTION:Compound fireproof tapes 8, 10, integrally formed by pasting together a glass tape 6 or synthetic resin-made tape 9 in a composite mica tape 7 on a conductor 2, are wound in such a manner that the second winding parts 8B, 10B are superposed on the first winding parts 8A, 10A, and on these second winding parts 8B, JOB, the third winding parts 8C, 10C are piled together so as to be piled together partly in the first winding parts 8A, 10A. On these wound compound fireproof tapes 8, 10, an insulator 4 is extruded to cover the tapes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof electric wire capable of significantly improving withstand voltage performance without lowering insulation resistance when exposed to high heat or flame due to fire or the like.

[0002]

2. Description of the Related Art Generally, in a place where a large number of people gather, such as in a theater or a department store, in case of a fire or the like, an emergency exit light such as an emergency exit light is provided in order to safely guide people on the site to the emergency exit. , It is required to keep the lights on for a certain period of time to complete evacuation. Therefore, with regard to fire-resistant electric wires used for wiring fire-extinguishing equipment, alarm equipment, and evacuation equipment in fire-resistant objects, the Japan Cable Manufacturers Association has voluntarily established its own certification criteria for fire-resistant electric wires, etc. We are trying to ensure the quality of materials.
In the present specification, the term "fireproof electric wire" refers to a generic term for cables having fireproof performance specified by Fire Service Agency Notification No. 7 of 1978. This fire resistant wire has a structure as shown in FIG. That is, in the fireproof electric wire 1, a fireproof layer 3 is formed on the outer circumference of a conductor 2, the outer circumference is covered with an insulator 4 made of polyethylene, and a sheath 5 made of polyvinyl chloride resin or polyethylene resin is further provided on the outer circumference. It is configured by coating.

As shown in FIG. 9, the fireproof layer 3 has a composite fireproof tape 8 in which a laminated mica tape 7 is attached to a glass tape 6 made of an inorganic material such as a glass fiber cloth so as to be integrated. The glass tape 6 is, for example, 900
It is a cross fabric in which yarns before and after denier are arranged in the lengthwise and widthwise direction at 30 to 60 threads / inch. Alternatively, the refractory layer 3 has a structure shown in FIG.
As shown in FIG. 3, there is a composite fireproof tape 10 in which a laminated mica tape 7 is attached to a plastic film 9 so as to be integrated. The plastic film 9 has a thickness of 10 μm, for example.
It is formed of PE, PP, PET or the like having a thickness of about 25 μm. The integrated mica tape 7 is made by adhering scale-like mica foil with silicone resin and laminating it into a tape shape. The scale-like mica foil is suitable for handling because the synthetic mica is scale-like, but it is expensive, so
A natural mica formed like a scale is used. As the synthetic mica, fluoric mica containing talc as a main component is suitable. The silicone resin is an organosilicon compound, and a resinous substance can be obtained by forming a network bond by hydrolysis and polycondensation of organohalogenosilane (R ₂ SiX ₂ ).
The properties of this silicone resin are extremely excellent in heat resistance and moisture resistance, and excellent in electrical insulation performance.

In the conventional fireproof electric wire 1, a composite fireproof tape 8 (10) having a total thickness of 0.1 mm to 0.2 mm and cut to an appropriate width is formed on the fireproof layer 3 formed on the conductor 2. It was formed by using four sheets. As a method of forming this, the composite fireproof tape 8 (10) was vertically attached to the conductor 2 or was wound in layers. The fire-resistant electric wire 1 formed by stacking the composite fire-resistant tape 8 (10) on the conductor 2 has been the first known in the prior art.
As shown in FIG. 3, the composite fireproof tape 8 (10) is placed on the conductor 2.
There is a structure having a two-layer structure in which the composite fire-resistant tape 8 (10) is lap-wound and the composite fire-resistant tape 8 (10) is lap-wound ¼ on the composite fire-resistant tape 8 (10). The overlap margin of the composite fireproof tape 8 (10) is indicated by a in FIG. b shows the tape width of the composite fireproof tape 8 (10). The ratio of the tape width b to the overlap margin a is a: b = 1: 2. The insulator 4 is extruded and coated on the composite fireproof tape 8 (10) wound over the conductor 2, and the sheath 5 is further coated on the insulator 4. Secondly, as shown in FIGS. 14 to 16, a composite fireproof tape 8 (10) is lapped 1/6 on the conductor 2 and the composite fireproof tape 8 (10) is wound on the lapped composite fireproof tape 8 (10). 8 (10)
There is a structure having a two-layer structure in which 1/6 is wound. The overlap margin of this composite fireproof tape 8 (10) is shown in FIG.
It is indicated by c in 4. d is composite fireproof tape 8 (10)
Shows the tape width. This tape width d and overlap c
The ratio of c: d = 1: 6. The insulator 4 is extruded and coated on the composite fireproof tape 8 (10) wound over the conductor 2, and the sheath 5 is further coated on the insulator 4.

[0005]

However, looking at the cross section of the refractory layer 3 wound on the conductor 2 of the conventional refractory electric wire 1, as shown in FIGS. The fireproof tape 8 (10) is used.
In particular, in the overlapping portion F where the fireproof layer 3 is composed of two composite fireproof tapes 8 (10), the composite fireproof tape 8 (1) is wound by the winding pressure when the composite fireproof tape 8 (10) is wound.
The mica foil of the laminated mica tape 7 constituting 0) is subjected to so-called "bullying" in which cracks 11 are generated by the tightening pressure of the composite fireproof tapes to be laminated.

Therefore, in the conventional fireproof electric wire 1,
From the crack 11 in the overlapping portion F of the composite fireproof tape 8 (10) wound around the conductor 2, the melted material of the insulator 4 and the sheath 5 in which the fireproof electric wire 1 is melted by being exposed to high heat or flame due to fire or the like. Has entered the conductor 2 direction and becomes a conductive carbide due to incomplete combustion, resulting in a decrease in insulation resistance as a fire resistant electric wire and an extremely poor withstand voltage.

An object of the present invention is to prevent cracks from being formed in the overlapped portion of the composite fire-resistant tape wound around the conductor, and even when the insulator and the sheath are melted by being exposed to high heat or flame due to fire or the like, The melted material of the insulator and sheath does not enter in the conductor direction, and even if the melted material of the insulator and sheath becomes conductive carbide due to incomplete combustion, the insulation resistance of the fire resistant wire does not decrease. , To prevent a decrease in withstand voltage.

[0008]

The invention according to claim 1 is
A composite fireproof tape made by laminating glass tape or synthetic resin tape on a mica tape laminated on a conductor,
The second winding portion is superposed on the first winding portion, and the third winding portion is superposed on the second winding portion so as to overlap a part of the first winding portion. A fireproof electric wire is formed by extruding and covering an insulator on the wound composite fireproof tape.

According to a second aspect of the present invention, a composite fireproof tape in which a glass tape or a synthetic resin tape is attached to and integrated with a laminated mica tape is provided in a ratio of 1.1 / 2 between the conductor and the insulator.
A fireproof electric wire is constructed by winding and interposing ~ 1.3 / 2 layers. In the invention according to claim 3, the first composite fire-resistant tape in which a glass tape or a synthetic resin tape is attached to and integrated with a laminated mica tape on a conductor is 1.1.
/ 2 to 1.3 / 2 is wound in a layered manner, and a glass tape or a synthetic resin tape and an integrated mica tape are further laminated on the composite fireproof tape to form a second composite fireproof tape ¼. A fireproof electric wire is constructed by using an insulated conductor obtained by winding the layers in a stack and extruding and covering an insulator on the second composite fireproof tape.

[0010]

According to the first aspect of the present invention, the composite fireproof tape in which the glass tape or the synthetic resin tape is attached to the laminated mica tape on the conductor to be integrated, and the second fireproof tape is formed on the first winding portion. A winding is formed, the first winding on the second winding
The lap winding is performed so that a third winding portion that overlaps with a part of the winding portion is formed. Then, the composite fireproof tape is extruded and coated with an insulating material. According to this structure, the composite fireproof tape is wound in a three-layered state in which the end portions of the laminated layers are superposed. In this way, the exposed portion of the overlapping layer is in a state of being overlapped on the two-layered structure in which the second winding part is overlapped on the first winding part, so that the lower layer is formed at the end of the overlapping layer. It is possible to prevent the occurrence of cracks in the overlapping portion of the composite refractory tape that is wound around the conductor because it is not pressed.

Since the composite fireproof tape does not crack in the overlapped portion, even if the insulator and the sheath are melted by being exposed to high heat or flame due to fire or the like, the melted material of the insulator and the sheath enters in the conductor direction. Even if the melted material of the insulator and the sheath becomes conductive carbide due to incomplete combustion, the insulation resistance of the fire resistant wire does not decrease. Further, it is possible to prevent the withstand voltage of the fireproof wire from being lowered.

According to the second aspect of the present invention, the composite fireproof tape in which the laminated mica tape is laminated on the conductor with the glass tape or the synthetic resin tape to form an integrated fireproof tape is 1.1 / 2.
Wrap in a 1/2 layer. The composite fireproof tape is formed by extruding and covering an insulator. According to this structure, the composite fireproof tape is wound in a three-layered state in which the end portions of the laminated layers are superposed. In this way, since the end portions of the overlapping layers are overlapped on the two sheets, the lower layer is not pressed by the end portions of the overlapping layers, and the composite fire-resistant tape wound on the conductor is prevented. Does not cause cracks in the overlapping portion.

Since the composite fireproof tape does not crack in the overlapped portion, even if the insulator and the sheath are melted by being exposed to high heat and flame due to a fire or the like, the melted material of the insulator and the sheath enters in the conductor direction. Even if the melted material of the insulator and the sheath becomes conductive carbide due to incomplete combustion, the insulation resistance of the fire resistant wire does not decrease. Further, it is possible to prevent the withstand voltage of the fireproof wire from being lowered.

According to the third aspect of the present invention, the composite fireproof tape in which the integrated mica tape is laminated on the conductor with the glass tape or the synthetic resin tape to be integrated into 1.1 / 2.
Wrap in a 1/2 layer. On top of this wound first composite fire-resistant tape, a second composite fire-resistant tape 1
/ 4 Wrap in layers. Then, an insulator is extruded and coated on the second composite fireproof tape. According to this structure, a three-layered state is formed in which the end portions of the lapped layers formed by wrapping the first composite refractory tape on top of each other overlap three. In this way, since the end portion of the overlapping layer is in a state of overlapping on the two sheets, the lower layer is not pressed by the end portion of the overlapping layer, and the first composite layer wound on the conductor is formed. Does not cause cracks in the overlapping part of the fireproof tape. Also, the first
Since the second composite fire-resistant tape is further wrapped around the second composite fire-resistant tape, the end portions of the laminated layers of the second composite fire-resistant tape will be in a state of overlapping 5 sheets, further improving fire resistance. You can

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention of claims 1 and 2 and claim 3
An embodiment of the described invention will be described. 1-3,
An embodiment of the fireproof electric wire according to the inventions of claims 1 and 2 is shown. In the figure, the total thickness on the conductor 2 is 0.1 mm.
Composite fire-resistant tape 8 cut to an appropriate width of ~ 0.2 mm
(10), the second winding portion 8B (10B) is overlapped on the first winding portion 8A (10A), the second winding portion 8B
A third winding portion 8C (10C) is wound on (10B) so as to overlap with a part of the first winding portion 8A (10A). The superposition of the first winding portion 8A (10A) and the second winding portion 8B (10B) of the composite fireproof tape 8 (10) is specifically
It is wound in a stack of 1.1 / 2 to 1.3 / 2. The overlap margin of the composite fireproof tape 8 (10) is indicated by A in the figure. B shows the tape width of the composite fire-resistant tape 8 (10). The ratio of the tape width B to the overlap margin A is A: B = 1.1 (˜1.3): 2. The insulator 4 is extruded and coated on the composite fireproof tape 8 (10) wound over the conductor 2, and the sheath 5 is further coated on the insulator 4. When wound in a 1.1 / 2 to 1.3 / 2 lap in this manner, the end portion of the lap layer in which the composite fireproof tape 8 (10) is lapped is 1 as shown in C in FIG. The width of / 20 to 3/20 is further overlapped, the second winding portion 8B (10B) is overlapped on the first winding portion 8A (10A), and the second winding portion 8B (10B) is further overlapped. Third winding part 8C on top of
(10C), the composite fireproof tape 8 (10) is in a three-layer state in which three sheets are overlaid. In this way, the end C of the superposed layer is further overlapped on the two superposed layers, so that the composite fireproof tape 8 (10) below is not pressed by the end of the superposed layers, The composite fireproof tape 8 (10) wound around the conductor 2 is not cracked in the overlapping portion. Since the composite fireproof tape 8 (10) does not crack in the overlapping portion, even if the insulator 4 and the sheath 5 are melted by being exposed to high heat or flame due to a fire or the like, the insulator 4 and the sheath 5 are not melted.
Does not enter in the direction of the conductor 2, and even if the melt of the insulator 4 and the sheath 5 becomes conductive carbide due to incomplete combustion, the insulation resistance of the fire resistant electric wire 1 may decrease. Absent. Further, it is possible to prevent the withstand voltage of the fireproof electric wire 1 from decreasing.

4 to 6 show one embodiment of the fireproof electric wire according to the invention of claim 3. In the figure, on the conductor 2, the first composite refractory tape 8 (10) having a total thickness of 0.1 mm to 0.2 mm and cut into an appropriate width is provided at 1.1 / 2 to
It is wound in a 1.3 / 2 stack. The overlap area of the first composite refractory tape 8 (10) is indicated by A in the figure. B indicates the tape width of the first composite fireproof tape 8 (10). The ratio of the tape width B to the overlap margin A is A: B = 1.1 (˜1.3): 2. Further, the second composite fire-resistant tape 8 (10) is lapped on the first composite fire-resistant tape 8 (10) which is wound in a lap, and has a two-layer structure. The overlap margin of the second composite fireproof tape 8 (10) is indicated by D in the figure. E indicates the tape width of the second composite fireproof tape 8 (10). The ratio between the tape width E and the overlap margin D is D: E = 1: 4. The tape width E of the second composite fireproof tape 8 (10) may be different from the tape width B of the first composite fireproof tape 8 (10), or may be the same. Absent. This first composite fireproof tape 8 (10)
The second composite fireproof tape 8 (1
0), the insulator 4 is extruded and covered, and the insulator 4
Is covered with the sheath 5.

Thus, the first composite fireproof tape 8 (1
0) is wound in a 1.1 / 2 to 1.3 / 2 stack,
The edge portion of the overlapping layer is 1 /
The portion of 20 to 3/20 is further overlapped to form a three-layered state in which three sheets are overlapped. In this way, the end C of the layer to be laminated is in a state of being further overlapped on the two layers, so that the composite fireproof tape 8 (10) below the composite fireproof tape 8 ( 10) is not pressed, and cracks are not generated in the overlapping portion of the first composite refractory tape 8 (10) wound on the conductor 2. Further, since the second composite fire-resistant tape 8 (10) is further wound on the first composite fire-resistant tape 8 (10), the overlapping portion of the second composite fire-resistant tape 8 (10) is 5 The sheets are stacked, and the fire resistance can be further improved. In this way, the second composite fireproof tape 8 (10) is further covered with a second
Because the composite fireproof tape 8 (10) of
Even if the insulator 4 and the sheath 5 are melted by being exposed to high heat or flame due to a fire or the like, the melted substance of the insulator 4 and the sheath 5 is
Even if the melted material of the insulator 4 and the sheath 5 becomes conductive carbide due to incomplete combustion, the insulation resistance of the fire resistant electric wire 1 does not decrease. Further, it is possible to prevent the withstand voltage of the fireproof electric wire 1 from decreasing. In this way, the weak part of the fireproof layer 3 (two fireproof tapes)
By reinforcing the above, it is possible to obtain an inexpensive fireproof electric wire having a significantly improved insulation resistance value and withstand voltage value and stable quality.

Table 1 shows the characteristic test results of the characteristics of the refractory electric wire according to the second aspect of the present invention and the characteristics of the conventional refractory electric wire. The fire-resistant wire of the example used for the characteristic test was 0.15 mm thick on a conductor having a diameter of 2.0 mm.
The first composite fire-resistant tape having a width of 12 mm is wound in a 1.1 / 2 stack, and 0.1 is further laid on the first composite fire-resistant tape.
A second composite refractory tape having a thickness of 5 mm and a width of 12 mm is wound in a 1/4 stack, an insulator is extruded on the second composite refractory tape, and then a non-halogen PE sheath is extruded. Formed flat cable 1.3m
Is the length of. In addition, the conventional fire resistant wire,
1st 0.15mm thickness x 12mm width on a conductor with a diameter of 2.0mm
The composite fireproof tape of No. 1 is wound in a 1/2 stack, and the second composite fireproof tape having a thickness of 0.15 mm x 12 mm is further wound in a 1/4 stack on the first composite fireproof tape. Two
The insulation is extruded on the composite fireproof tape of
After that, a flat cable formed by extruding a non-halogen PE sheath by extrusion has a length of 1.3 m. The materials and thicknesses of the insulator and the non-halogen PE sheath are the same in both the embodiment and the conventional example.

This characteristic test was carried out by placing the refractory electric wire horizontally in the heating furnace in both the examples and the conventional examples, and placing both ends of the refractory electric wire over the inner wall surface of the heating furnace so as to contact them. This heating furnace is heated by a gas burner, and the furnace temperature is heated to 840 ° C. in 30 minutes according to the temperature curve defined in JIS A 1304. The heating start temperature of the sample is 200 ° C. or lower.

Table 1 Among the test conditions in the insulation resistance measurement test in Table 1,
“Before heating (MΩ · 1.3 m)” was obtained by arranging in a heating furnace and then measuring the insulation resistance value between the conductor and the fixed wire at room temperature with an insulation resistance measuring instrument of DC 500 V / 100 MΩ. The resistance value (unit is MΩ). In addition, “heating 30 minutes (MΩ · 1.3 m)” means that the insulation resistance value between the conductor and the fixed line when the temperature is raised to 840 ° C. in 30 minutes by heating in a heating furnace. It is a resistance value (unit is MΩ) obtained by measurement with an insulation resistance measuring device of 500 V / 100 MΩ.

Among the test conditions in the dielectric strength test in Table 1, "V / 1 minute before heating" means that a predetermined AC voltage is applied between the conductor and the fixed wire at room temperature for 1 minute after being placed in the heating furnace. It is to measure whether the insulation state can be maintained when applied. In addition, "V / 30 minutes during heating" means that a predetermined AC voltage is maintained between the conductor and the fixed wire from the start of heating (0 minutes) to the end of heating (30 minutes) by arranging in the heating furnace. Then, it is measured whether or not the insulation state can be maintained when applied. Furthermore, “V / 1 minute after heating” means that the sample is placed in a heating furnace and heated, and immediately after heating to 840 ° C. in 30 minutes to extinguish the burner fire,
It is to measure whether or not the insulation state can be maintained when a predetermined AC voltage is applied between the conductor and the fixed wire for 1 minute. Table 1
During the test conditions in the dielectric breakdown voltage measurement test in
"After heating" is to measure the voltage value when dielectric breakdown occurs by further increasing the voltage after passing the dielectric strength test. The standards in Table 1 refer to the fire resistance certification standards established and announced by the Fire Department.

In Table 1, the insulation resistance value of the refractory wire before heating is defined by the standard to be 50 MΩ or more. The insulation resistance value before heating has a characteristic higher than the standard in both the embodiment and the conventional example. Generally, when an insulator is heated, the insulation deteriorates and the insulation resistance decreases. Therefore, in the standard, the insulation resistance value after heating (when the furnace temperature reaches 840 ° C.) is set to 0.4 MΩ or more. This insulation resistance has a characteristic higher than the standard in both the embodiment and the conventional example. But,
Comparing the example with the conventional example, the example shows 25 to 30M.
In contrast, the conventional example has a characteristic of 1.0 to 7.0 MΩ, which is much lower than that of the example. Further, in the dielectric strength test of the fireproof wire, a voltage is applied between the conductor of the sample and the fixed wire to increase the voltage, and the voltage value when the dielectric breakdown occurs is measured. The test condition “V / 1 minute before heating” requires that no dielectric breakdown occurs when an AC voltage of 1500 V is applied between the conductor and the fixed line for 1 minute at room temperature before heating is started. . In this "V / 1 minute before heating" dielectric strength test, both the example and the conventional example have standard characteristics. Test condition "V / 30 minutes during heating"
According to the standard, it is required that no dielectric breakdown occurs when an AC voltage of 600 V is continuously applied between the conductor and the fixed line from the start of heating (0 minutes) to the end of heating (30 minutes). . In the "V / 30 minutes during heating" dielectric strength test, both the example and the conventional example have standard characteristics. According to the standard of "V / 1 minute after heating", the sample is placed in a heating furnace and heated, and the temperature is raised to 840 ° C in 30 minutes to extinguish the burner fire.
It is required that no dielectric breakdown occurs when an AC voltage of 00V is applied for 1 minute. This "after heating V / 1
In the “dielectric strength test” of “Min”, both the example and the conventional example have standard characteristics.

The breakdown voltage of the refractory wire is not specified in the standard, but when the breakdown voltage immediately after the furnace temperature is heated to 840 ° C. according to a predetermined standard is measured, the conventional example shows 1800. In contrast to 2500 V, the embodiment shows a much higher value of 3000 to 3500 V. That is, it can be seen that the example has a high dielectric breakdown voltage even when exposed to a high temperature, and when used in a fireproof wire, the safety is higher when exposed to a high temperature as compared with the conventional example. As is clear from the above characteristic test of the fireproof wire, both the examples and the conventional examples satisfy the fireproof certification standard set by the Fire Department, but the insulation resistance when exposed to the high temperature, which is the most important fireproof wire. It can be seen that the embodiment is far superior to the conventional example in that the decrease in the dielectric constant is small and the decrease in the dielectric breakdown voltage when exposed to high temperature is small.

FIG. 7 shows another embodiment of the fireproof electric wire according to the invention of claim 1. In the figure, this embodiment is different from the embodiment shown in FIG. 1 in that the embodiment shown in FIG. 1 is a single core wire, whereas this embodiment is formed by twisting a large number of fireproof electric wires shown in FIG. The point is that it is a fireproof electric wire composed of stranded wires. That is, 20 is a stranded fireproof wire, 2
1 is a refractory wire. The refractory element wire 21 has a refractory layer 23 formed by wrapping the fireproof tape 8 (10) shown in FIG. 1 on the outer periphery of a conductor 22 made of copper.
An insulator 24 is extrusion-coated on the refractory layer 23. A plurality (three in the present embodiment) of the refractory wires 21 are twisted together, and an inclusion 25 is put therein, and is pressed by a holding tape 26 having a substantially circular cross section to form a polyvinyl chloride resin or an outermost layer. The fire resistant electric wire 20 is formed by extruding and covering a flame-retardant sheath 27 made of a halogen-free polyethylene resin.

[0025]

According to the first aspect of the present invention, the composite fireproof tape in which the glass mica or the synthetic resin tape is laminated on the conductor and the integrated mica tape is integrated on the conductor is provided on the first winding portion. Since the second winding portion is overlapped and the third winding portion is wound so as to overlap the second winding portion so as to overlap a part of the first winding portion, the third winding portion is overlapped at the time of winding. The "bullying" of the mica foil at the part is eliminated, and it is possible to prevent carbides from entering the refractory layer during combustion, and it is possible to greatly improve the insulation resistance value and the withstand voltage value.

According to the second aspect of the present invention, a composite fireproof tape in which a glass tape or a synthetic resin tape is attached to and integrated with a laminated mica tape is provided between the conductor and the insulator.
Since 1/2 to 1.3 / 2 is wrapped around and intervened, there is no "bullying" of the mica foil at the overlapped portion during winding, and carbide is prevented from entering the refractory layer during combustion. It is possible to significantly improve the insulation resistance value and the withstand voltage value.

According to the third aspect of the present invention, there is provided a first composite refractory tape in which a laminated mica tape is laminated on a conductor with a glass tape or a synthetic resin tape to form a 1.1.
/ 2 to 1.3 / 2 is wound in a layered manner, and a glass tape or a synthetic resin tape and an integrated mica tape are further laminated on the composite fireproof tape to form a second composite fireproof tape ¼. Since it is constructed by using an insulated conductor obtained by winding the fireproof tape on the second composite fireproof tape by extruding and covering the insulator on the second composite fireproof tape, the overlap of the fireproof layers after winding one fireproof tape is 2 ~ 3 sheets, "bullying" of the mica foil at the lap part during winding is eliminated, and as a result, the refractory material is prevented from entering during combustion, and the second piece of refractory tape is laid on top of it. Since the refractory layers are overlapped with one to two, the refractory layer can be formed with 3 to 5 refractory tapes even though the two refractory tapes are used as in the conventional case, and the insulation resistance value, The withstand voltage value can be significantly improved.

[Brief description of drawings]

FIG. 1 is a view showing a state in which a fire resistant tape is lapped around a conductor showing an embodiment of a fire resistant electric wire according to the invention of claim 1.

FIG. 2 is a cross-sectional view of a fireproof electric wire in which a fireproof tape is wound around the conductor shown in FIG.

FIG. 3 is a vertical cross-sectional view of a fireproof electric wire in which a fireproof tape is wound around the conductor shown in FIG.

FIG. 4 is a view showing a state in which a fire resistant tape is lapped around a conductor showing an embodiment of the fire resistant electric wire according to the invention of claim 2;

5 is a cross-sectional view of a fireproof electric wire in which a fireproof tape is wound around the conductor shown in FIG.

FIG. 6 is a vertical cross-sectional view of a fireproof electric wire in which a fireproof tape is wound around the conductor shown in FIG.

FIG. 7 is a diagram showing an embodiment of a fireproof electric wire in which a plurality of fireproof electric wires according to the invention of claim 1 are twisted together.

FIG. 8 is a cross-sectional view showing the structure of a conventional fireproof wire.

9 is a diagram showing the structure of the conventional fireproof tape shown in FIG.

10 is a diagram showing the structure of another conventional fire-resistant tape shown in FIG.

FIG. 11 is a diagram showing a state in which a fireproof tape of a conventional fireproof wire is wound in layers.

12 is a cross-sectional view of a fire resistant electric wire in which a fire resistant tape is wound around the conductor shown in FIG.

FIG. 13 is a vertical cross-sectional view of a fireproof electric wire in which a fireproof tape is wound around the conductor shown in FIG.

FIG. 14 is a diagram showing another state in which the fire-resistant tape of the conventional fire-resistant electric wire is wrapped in another layer.

15 is a cross-sectional view of a fire resistant electric wire in which a fire resistant tape is wound around the conductor shown in FIG.

16 is a vertical cross-sectional view of a fire resistant electric wire in which a fire resistant tape is wound around the conductor shown in FIG.

[Explanation of symbols]

1,20 …………………………………………………… Fireproof wire 2,22 …………………………………………………… Conductor 3,23 ……………………………………………………… Refractory layer 4,24 …………………………………………………… Insulator 5,17 …… …………………………………………… Flame-retardant series 6 ………………………………………………………… Glass tape 7… ……………………………………………………… Integrated mica 8,10 ……………………………………………… Fireproof tape 8A, 10A ………………………………………………… First
Winding part 8B, 10B …………………………………………………… Second
Winding part 8C, 10C ……………………………………………… The third
Winding part 9 ………………………………………………………… Plastic film 11 ………………………………………………………… Crack 21 ………………………………………………………… Refractory element wire 25 ………………………………………………………… Inclusion 26 ……………………………………………………………… Presser foot tape 27 ………………………………………………………… Flame retardant sheath

Claims (3)

[Claims] 1. A composite refractory tape in which a glass mica or a synthetic resin tape is laminated on a conductor and laminated with a mica tape to form a composite refractory tape, wherein a second winding part is overlapped on a first winding part. A second winding part is wound on the second winding part so as to overlap the first winding part so that the third winding part is overlapped, and an insulator is extruded and coated on the wound composite fireproof tape. Fire resistant wire characterized by 2. A composite fire-resistant tape obtained by laminating a glass tape or a synthetic resin tape to an integrated mica tape and winding the laminated composite mica tape between a conductor and an insulator in a 1.1 / 2 to 1.3 / 2 overlap. Fireproof electric wire characterized by being interposed. 3. A first structure in which a mica tape is laminated on a conductor and a glass tape or a synthetic resin tape is attached to the conductor for integration.
No. 2 which is obtained by winding the composite fireproof tape of 1.1 / 2 to 1.3 / 2 in a layered manner, and further adhering a glass tape or a synthetic resin tape and an assembled mica tape on the composite fireproof tape. 1. A fireproof electric wire, characterized in that the composite fireproof tape of (1) is wound in a 1/4 stack, and an insulating conductor is formed by extruding and covering an insulator on the second composite fireproof tape.