JPH0234732Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a fire-resistant electric wire.

An example of a conventional fireproof electric wire is shown in FIG.

In the figure, 1 is a refractory wire core, and these are coated with rubber over a conductor 2 via a predetermined refractory layer 3.
It is constructed by extruding a plastic insulation layer 4. 5 is an optional inclusion, and 6 is a rubber/plastic sheath.

More specifically, the fireproof layer 3 is made of a continuous fiber tape made of glass fiber woven fabric, glass fiber nonwoven fabric, asbestos fiber woven fabric, glass fiber woven fabric, carbon fiber woven fabric, carbon fiber woven fabric, etc. as shown in FIG. It is composed of a wrapped layer of a composite film 9 in which a laminated mica foil 8 is laminated on one side of a base material 7 such as a plastic sheet. In addition, in the case of conventional fire-resistant electric wires, the base material 7 of the composite film 9 used therein is without exception either an unslit fiber cloth tape or a plastic sheet.
-22083, JP-A-57-21012).

However, this type of refractory electric wire is considerably more expensive than ordinary electric wire, and therefore there is a strong demand for improvements in price. The main reason why fireproof wires are more expensive than ordinary wires is the use of the fireproof layer 3.

On the other hand, in this fireproof layer 3, the base material 7 is used to support the laminated mica foil 8,
Therefore, from the viewpoint of the fire resistance properties of the electric wire, it is essentially unnecessary.

Considering this, the most important point in improving the cost of fire-resistant electric wires lies in how well the base material 7 can be improved.

The present invention has been developed in view of the above points, and by skillfully improving the base material, it is possible to improve the price without sacrificing the various properties that electric wires originally require, such as fire resistance. The purpose is to provide a fire-resistant electric wire that can achieve

That is, the gist of the present invention is to stack a large number of tapes with splits at predetermined intervals in arbitrary directions such as vertically, horizontally, diagonally, etc. on the composite film base material constituting the fireproof layer, and then to stack tapes at predetermined intervals at tape intersections. The point is that a base fabric made by adhering or fusing similar materials is used.

Specifically, as the above-mentioned tape with many cracks, for example, a paper tape with a crack, a stretched polyethylene tape with a crack, a stretched polypropylene tape with a split, a stretched polyester tape with a split, a stretched nylon tape with a split, etc. are used. .

For example, as shown in FIG. 4, a plurality of tapes with multiple splits are provided above a tape material 13 such as paper tape, stretched polyethylene tape, stretched polypropylene tape, stretched polyester tape, stretched nylon tape, etc., which runs in the longitudinal direction. blade 14
The blade 14 is raised and lowered at predetermined intervals.
It is manufactured by cutting 15 the tape material 13 intermittently. It is conceivable to use tape material 13 that matches the width of the final product in advance, but rather, it is better to use a tape material that is initially wide and cut it to match the width of the final product after cutting. is preferable.

The split tape as a final product usually has a width of about 1 to 2 mm, within which there is a length of about 5 to 10 mm.
Many mm-sized splits are formed. Furthermore,
Approximately 2 to 3 such divisions are formed in parallel in the width direction of the tape, and at intervals of approximately 2 to 5 mm in the longitudinal direction.

Next, an embodiment of the fire-resistant electric wire of the present invention will be explained with reference to the accompanying drawings.This embodiment is based on the fire-resistant electric wire shown in FIG.
As the base material 7, a nonwoven fabric 10 shown in FIG. 3 is used.

To explain the non-woven fabric 10, it is made by laminating the split tape 11 produced by making many splits in the tape material 13 mentioned above at appropriate intervals in any direction such as vertically, horizontally, diagonally, etc. It is made by adhering or fusing the tapes 11 together at the portion 12. By sufficiently increasing the voids enclosed in the nonwoven fabric 10, the amount of material used can be significantly reduced compared to conventional fire-resistant wires, that is, when a base material made of unbroken fibers is used. There is.

In this embodiment, a composite film made by laminating and adhering scale-like mica to one side (or both sides) of the nonwoven fabric 10 or adhering a laminated film of scale-like mica is wrapped vertically or horizontally on the conductor 2. The fireproof layer 3 is formed by winding.

Incidentally, when winding the above composite film onto the conductor 2, if the tensile strength of the film is insufficient, it is advisable to insert an arbitrary reinforcing wire such as a glass thread into the film.

According to the above-described fire-resistant electric wire of this embodiment, as the base material of the composite film constituting the fire-resistant layer, tapes with cracks are laminated at predetermined intervals in any direction such as vertically, horizontally, diagonally, etc. Since the tape uses a base fabric made by adhering or fusing the tapes together, the amount used can be significantly reduced compared to conventional base materials, such as unbroken fiber cloth or plastic sheets. Therefore, the price of the electric wire can be improved to that extent.
In other words, in a split tape made by making a large number of cracks in the tape material, each split contains a considerable amount of voids, making the entire tape resemble a foam material, and as a result, it is different from the conventional tape material. The material density per unit volume of tape is much lower than that of split tape, and the amount of material used per unit volume of tape, and by extension, the amount of material used per unit volume of base material, is significantly lower than that of conventional tapes. It costs significantly less in comparison.

In addition, as a result of being able to reduce the amount of material used for the base material, it is possible to reduce the amount of contaminants such as carbides that are generated in the refractory layer during wire combustion that degrade electrical properties, thereby improving the electrical properties of the electrical wire. It also has the advantage of being able to

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an example of a refractory electric wire, Fig. 2 is an explanatory diagram of a composite film used in the above-mentioned refractory electric wire, and Fig. 3 is an explanatory diagram of a nonwoven fabric made of a split tape used in the refractory electric wire of this embodiment. FIG. 4 is an explanatory view of the manufacturing state of the split tape. 1; fireproof electric wire, 2; conductor, 3; fireproof layer, 4; insulating layer, 5; inclusion, 6; sheath, 7; base material, 8;
Mica layer, 9; Composite film, 10; Nonwoven fabric, 1
1; Slit tape, 12; Tape intersection, 1
3; Tape material, 14; Blade.

Claims (1)

[Claims for Utility Model Registration] 1. In a fire-resistant electric wire in which a rubber/plastic insulating layer is provided on a conductor via a fire-resistant layer, the fire-resistant layer is applied to a tape with a large number of slots in any direction such as vertically, horizontally, diagonally, etc. It is characterized by being composed of a wrapped layer of a composite film in which scale-like mica is laminated on one or both sides of a base fabric formed by laminating the tapes at predetermined intervals and then adhering or fusing the tapes together at the intersections of the tapes. Fireproof electric wire. 2. Scope of Utility Model Registration Claims No. 1 for Utility Model Registration Using a Split Paper Tape, Split Stretched Polyethylene Tape, Split Stretched Polypropylene Tape, Split Stretched Polyester Tape, Split Stretched Nylon Tape, etc. The fireproof electric wire described in item 1. 3. The fire-resistant electric wire according to claim 1, which uses a layered film made of flaky mica as the mica.