JP5442093B1 - Connection structure of coated carbon fiber wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently energize a carbon fiber wire in which carbon fiber strands are bundled.
A connecting structure of a coated carbon fiber wire 4 is formed by peeling off a coating 4B of a terminal portion of a coated carbon fiber wire 4A in which a bundle of a large number of carbon fiber wires 41A is coated with a synthetic resin material and forming a coating terminal portion. A pin 5 having a washer 5A attached to an intermediate portion is inserted into the carbon fiber wire 4A from the end of the carbon fiber wire 4A from which the conductive layer 6 is wound and the coating 4B is peeled off. The bundle of carbon fiber strands 4A is radially diffused by a washer 5A, the carbon fiber strand 4A is folded back on the conductive layer 6, and the washer 5A of the pin 5 is placed at the tip of the folded portion of the carbon fiber strand 4A. In a state of being in close contact with each other, it is inserted into the other end of the cylindrical connector 1 with the electric wire 3 connected to one end, and the connecting portion 2A of the cylindrical connector 1 is crimped.
[Selection] Figure 6

Description

  The present invention relates to a structure in which a coated carbon fiber wire in which a bundle of carbon fiber wires is covered with a synthetic resin material is bonded to a power supply side electric wire.

A carbon fiber wire that bundles a number of carbon fiber wires is higher in mechanical strength and lighter than metal wires such as copper or aluminum, and also has high chemical resistance. The use as a material is expanding, and the synthetic resin reinforced with the carbon fiber wire has recently been used for aircraft bodies, main wings, tail wings, and the like.
On the other hand, the carbon fiber wire has a property as a semiconductor element and generates heat when a voltage is applied, and thus is also used as a heat generating material. When the above carbon fiber wire is used as a heat generating material, the far-infrared radiation effect is higher, the heating rate is faster, and the power consumption compared to the nichrome wire-based heat generating material commonly used at present. There are various advantages, such as the amount being about half that of nichrome wire.
However, since the carbon fiber wire is a semiconductor element formed by bundling about 3,000 (3k) to 48,000 (48k) ultrafine carbon fiber strands having a diameter of 7 to 10 μm, like a nichrome wire. Unlike low-resistance conductors, special considerations are required to close the electrical contact in order to connect to the power supply side wires.
Conventionally, as a method of connecting a coated carbon fiber wire and a coated electric wire made of a metal such as copper or aluminum, a butt connection terminal 1 (connector) as shown in FIG. 9 is used, and the coated electric wire 3 and the coated carbon fiber are used. The connection ends 3C, 4C of the wire 4 are peeled off to expose the electric wire 3A and the carbon fiber wire 4A, and are inserted into the cylindrical connection portions 2A, 2B at both ends of the connector 1, respectively. As shown in FIG. 10, a configuration is adopted in which the connecting portions 2 </ b> A and 2 </ b> B of the connector 1 are crimped.
Alternatively, as shown in FIG. 11, the connecting end portion 4C of the coated carbon fiber wire 4 is bent inward (covered 4B side), and the bent portion is connected to the connecting portion 2B as shown in FIG. A configuration that is inserted into the connecting portion 2A and crimped is also employed. Further, the coating of the connection end 4C of the coated carbon fiber wire 4 is removed, and as shown in FIG. 13, the coating of the connection end 4C of the coated electric wire 3 is removed, and the coating is removed. There is also provided a configuration in which the connection end 3C of the electric wire 3A from which the coating is removed is spirally wound around the outer periphery of the connection end 4C of the fiber wire 4.

Special table 2009-518790 gazette

The above conventional connection structure can be used without any problem for a plug made of a conductor having a low electrical resistance such as an electric wire or a nichrome wire. However, in the case of a wire made of a semiconductor such as the carbon fiber wire 4A, the current concentrates on the outer peripheral portion contacting the plug 2 and the connecting portion 2A of the connector 1 or the spirally wound wire 3A, and the carbon fiber wire 4A. The current density tends to decrease as it goes inside. Then, especially when a large current such as a carbon heater flows, the current concentrates on the outer peripheral portion of the carbon fiber wire 4A, and this portion becomes a high temperature exceeding the set value, increasing the risk of fire and the like.
Further, when the connector 1 is used, there are many cases in which the end portions of the cylindrical connecting portions 2 and 2 of the connector 1 have a blade shape, and the carbon fiber wire 4A is cut. The number of carbon fiber strands that are not energized increases, leading to poor conductivity.
Furthermore, the filament (elementary wire) constituting the carbon fiber is a carbonized acrylic yarn having a diameter of 7 to 10 μm, and there is a possibility of breaking due to contact of a metal piece from the cross-sectional (lateral) direction.
The present invention solves the above-mentioned conventional problems, electrically connects the coated carbon fiber wire closely with the power supply side electric wire, performs efficient energization, and can sufficiently exhibit the original characteristics of the carbon fiber wire. The challenge is to do so.

As means for solving the above-mentioned problems of the present invention, the present invention peels off the coating of the terminal portion of the coated carbon fiber wire in which a bundle of a plurality of carbon fiber wires is coated with a synthetic resin material, and provides a conductive layer on the coated terminal portion. A pin having a washer attached to an intermediate portion is inserted into the inside of the carbon fiber wire from the end of the carbon fiber wire that has been wound and peeled off, and the bundle of carbon fiber wires is bundled by the washer of the pin. A cylindrical connector in which a wire is connected to one end in a state where the carbon fiber wire is folded radially on the conductive layer and the pin washer is in close contact with the tip of the folded portion of the carbon fiber wire. The connection structure of the coated carbon fiber wire is provided in which the connection portion of the cylindrical connector is crimped.
In general, the carbon fiber strand constituting the coated carbon fiber wire has a diameter of 7 to 10 μm and a direct current resistance value of 300 kΩ / m to 500 kΩ / m, and a predetermined number of carbon fiber strands are bundled to form the coated carbon fiber wire. Is configured.
The covering carbon fiber wire is preferably made of an insulating thermoplastic resin.
Further, the coating of the coated carbon fiber wire is a double coating of a synthetic resin material on the inside and a coating made of rubber or elastomer on the outside, and the conductive layer is formed on the inner coating surface by peeling the outer coating. It is desirable that

In the present invention, when the pin 5 is inserted into the connecting portion from the end portion of the carbon fiber wire 4A exposed by peeling off the coating 4B, the carbon fiber is washed by the washer 5A of the pin 5. The strands 41 of the line 4A are diffused radially. The diffused element wire 41 is further folded back onto the conductive layer 5 wound around the covered terminal portion by the washer 5A. With the washer 5A in close contact with the tip of the folded portion, the washer 5A is inserted into the other end of the cylindrical connector 1 with the electric wire 3 connected to one end, and the connecting portion 2 of the connector 1 is crimped. Then, most of the strands 4 diffused radially and folded on the conductive layer 5 are in close contact with the inner conductive layer 5 and the connection portion 2 of the outer connector 1. Therefore, intimate electrical contact is obtained among the connector 1, the carbon fiber wire 4, and the conductive layer 5, and the current through the electric wire 3 from the power source is efficiently transmitted from the connector 1 to the strand 41, and further the strand 41 Is transmitted to the conductive layer 5 and uniformized by the conductive layer 5 as a whole.
Therefore, in the present invention, the current density transmitted to the carbon fiber wire becomes uniform, and overheating due to current concentration, or the cutting of the carbon fiber wire by the end face of the connector, the failure due to the tensile force of the carbon fiber wire is eliminated, An electric current can be efficiently sent from the electric wire to the carbon fiber wire.

Explanatory drawing before pin insertion. Explanatory drawing after pin insertion. AA sectional drawing in FIG. Explanatory drawing of the state inserted in the connector. Explanatory drawing of the state which connected the carbon fiber wire and the electric wire via the connector. FIG. 6 is a side sectional view of the state of FIG. 5. Side cross-section explanatory drawing of a double covering carbon fiber wire. Graph of exothermic temperature test. Explanatory drawing before the connection of a prior art example. Explanatory drawing after the connection of a prior art example. Explanatory drawing before the connection of the conventional bending system. Explanatory drawing after the connection of the conventional bending system. Explanatory drawing of the conventional wire winding system.

The present invention will be described in detail below with reference to an embodiment shown in FIGS.
The coated carbon fiber wire 4 shown in FIG. 1 includes a carbon fiber wire 4A and a coating 4B that covers the carbon fiber wire 4A. For the coating 4B, for example, polyvinyl chloride (PVC), polyamide, polyester, acrylonitrile-butadiene-styrene resin (ABS), fluororesin, silicone resin, silicone rubber, or synthetic resins such as glass fiber, ceramic fiber, etc. A fiber reinforced resin (FRP) or the like in which fibers are mixed as a reinforcing material is used as a material. Generally, PVC is used as a coating material when the set exothermic temperature is 80 ° C. or lower, and polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyfluoride is used when the set exothermic temperature is higher than that. Fluorine resin such as vinylidene fluoride, silicon rubber, FRP, or the like is used as a coating material.
The carbon fiber wire 4A includes a bundle of a large number of carbon fiber wires 41A (hereinafter simply referred to as “wires”). The strand 41A generally has a diameter of 7 to 10 μm, and the DC resistance value of one strand 41A is about 400 KΩ / m. The strand 41A is normally bundled 3000 (3K), 6000 (6K), 24000 (24K), 36000 (36K), 48000 (48K) to form the carbon fiber 4A. Table 1 shows the relationship between the number of bundles and the DC resistance value.

[Table 1]
Number of bundles DC resistance (Ω / m)
3K 133
6K 67
12K 33
18K 22
24K 17
36K 11
48K 8
The DC resistance value varies somewhat depending on the manufacturer.

As shown in Table 1, the DC resistance value of a single wire is 400 KΩ / m. By bundling this, the DC resistance value per unit length (m) decreases, and heat is generated when a voltage is applied. Becomes a level that works as a body. For example, in an 18K carbon fiber wire 4A, the resistance value is 220Ω at a total length of 10m, and if a voltage of 100V is applied to both ends, a current of I = 100V / 220Ω≈0.45A flows from I = E / R, and power consumption Is a calorific value of V × I = 100 × 0.45 = 45 W per unit time, and P = RI ² to 220 × (0.45) ² = 44.55 W per second.

When the coated carbon fiber wire 4 is connected to the electric wire 3, as shown in FIG. 1, the coating 4B of the connection end 4C is peeled off to expose the carbon fiber wire 4A. The length of the exposed connection end (peeling portion) is usually about 5 to 15 mm .
Next, as shown in FIG. 2, a conductive layer 6 is formed by winding a conductive tape having an adhesive layer on the back surface of a tape of a metal foil such as a copper foil or an aluminum foil around the terminal portion of the coating 4 </ b> B. The length of the conductive layer 6 is set equal to or longer than the length of the peeled portion.
Thereafter, the pin 5 is inserted from the tip of the connection end 4C which is a peeling portion. As shown in FIG. 1, the pin 5 is obtained by soldering a washer 5A to an intermediate portion of the pin 5 having a diameter of about 0.5 to 0.9 mm.
When the pin 5 is inserted from the tip of the connection end 4C, the strand 41A of the carbon fiber wire 4A is spread radially in the 360 ° direction by the washer 5A of the pin 5 as shown in FIG.
In the pin 5, the washer 5 </ b> A serves as a stopper that moderately inserts the pin 5 into the coated carbon fiber wire 4 in addition to the function of radially expanding the strands 41 </ b> A of the carbon fiber wire 4 </ b> A as described above. It has the function of As long as these functions can be imparted to the pin 5, for example, the washer 5A is not limited to being soldered to the pin 5, and the washer 5A may be welded to or bonded to the pin 5. Instead of the washer 5A, a stopper may be provided at the intermediate portion of the pin 5 by bending or molding.

When the washer 5A of the pin 5 reaches the inner end of the outer connecting end 4C, the radially extending strand 41A is connected to the cylindrical connecting portion 2A at both ends as shown in FIGS. , 2B is externally fitted to the connecting portion 2A on the opposite side of the power source, whereby the group of the strands 41A is folded back onto the conductive layer 5, and crimping is performed on the connecting portion 2A. Do.
In this way, the strands 41A are folded back on the conductive layer 5, and are crimped approximately uniformly by 360 ° between the conductive layer 5 and the connection portion 2A of the connector 1.

Next, the covering 3B of the connecting portion 3C of the covered electric wire 3 is peeled to expose the electric wire 3A, and is inserted into the electric wire side connecting portion 2 of the connector 1 as shown in FIG. .
Then, as shown in FIG. 6, the electric wire 3 </ b> A of the covered electric wire 3 and the carbon fiber wire 4 </ b> A of the covered carbon fiber wire 4 are connected through the connector 1 while ensuring intimate electrical contact. Moreover, in the said connection state, the pin 5 is contacting with the electric wire 3A, and the electrical contact with 3 A of electric wires and carbon fiber wire 4A through this pin 5 is ensured.

In the above embodiment, the coated carbon fiber wire 4 was subjected to a single coating. However, in the present invention, as shown in FIG. 7, the coated carbon fiber wire 4 may employ a double coating structure in which the coating 4B includes an outer coating 41B and an inner coating 42B. In this case, the outer coating is made of an elastomer such as styrene elastomer, olefin elastomer, urethane elastomer, or rubber such as styrene-butadiene rubber, acrylonitrile-butadiene rubber, ethylene-propylene rubber, etc. The same resin material as in the case of the single coating is used.
In the case of the above double coating, the double coating 41B and 42B are peeled off at the connection end portion 4C of the coated carbon fiber wire 4 to expose the carbon fiber wire 4A, and the outer coating 41B is peeled off from the coating end by a predetermined length. Then, the inner coating 42B is exposed, and a conductive tape is wound around the exposed portion of the inner coating 42B to form the conductive layer 5.

The connection structure of the present invention (FIG. 6), the conventional connection structure (FIGS. 9 and 11), and a power source directly via an alligator clip at both ends of the carbon fiber wire in a state where the coating is only peeled off. An energization experiment was conducted on the connected comparative structures.
The coated carbon fiber wire 4 used in the experiment has a double coating, the outer coating 41B is made of urethane elastomer, and the inner coating is made of PVC. And as carbon fiber wire 4A, carbon fiber wire 4A (18K) which consists of 18,000 strands was used, and the thing of wire length 1.0m resistance 22.5ohm was used.
As setting conditions, applied voltage: AC18V, and for temperature measurement, the central portion of the carbon fiber wire in each connection structure was measured with a temperature recorder.
The measurement results are shown in FIG. In the figure, graph A is a connection structure of the present invention, graph B is a conventional connection structure shown in FIG. 10, graph C is a conventional bent connection structure shown in FIG. 12, and graph D is a graph of a direct connection structure using an alligator clip. is there.
Referring to FIG. 8, in the connection structure of the present invention, it is recognized that the heat generation temperature is higher (about 4 ° C. higher than B) and the rate of temperature increase is faster than graphs B and C employing the conventional connection structure. It is done. Further, it has been proved that the connection by the alligator clip (graph D) has no problem with a conductor, but cannot be used with a semiconductor such as carbon fiber.

  According to the connection structure of the present invention, since the carbon fiber wire can be efficiently energized, it is useful to be applied to floor heating by a carbon fiber wire, a snow melting heater for roofs and roads, and the like, which can be used industrially. .

DESCRIPTION OF SYMBOLS 1 Connector 2A, 2B Connection part 3 Electric wire 3A Electric wire 3B Covering 3C Connection part 4 Coated carbon fiber wire 4A Carbon fiber wire 41A Carbon fiber strand 4B Coating 4C Connection end part 5 Pin 6 Conductive layer

Claims (4)

  The ends of the coated carbon fiber wires in which a bundle of carbon fiber strands is coated with a synthetic resin material are peeled off, a conductive layer is wound around the coated terminal portions, and the ends of the carbon fiber wires are peeled off. A pin having a washer attached to an intermediate portion is inserted from the inside into the carbon fiber wire, and the bundle of carbon fiber wires is diffused radially by the washer of the pin, and the carbon fiber wire is passed through the conductive layer. Folded up, inserted into the other end of the cylindrical connector with the electric wire connected to one end, with the pin washer in close contact with the tip of the folded portion of the carbon fiber strand, and connected to the cylindrical connector A connection structure of coated carbon fiber wires, characterized in that the portions are crimped.   The carbon fiber strand constituting the coated carbon fiber wire has a diameter of 7 to 10 μm and a direct current resistance value of 300 kΩ / m to 500 kΩ / m, and a predetermined number of carbon fiber strands are bundled to form the coated carbon fiber wire. The connection structure of the covering carbon fiber wire of Claim 1 which comprises.   The connection structure of the coated carbon fiber wire according to claim 1 or 2, wherein the coating of the coated carbon fiber wire is made of an insulating thermoplastic resin. The coating of the coated carbon fiber wire is a double coating consisting of a synthetic resin material on the inside and a rubber or elastomer coating on the outside, and the conductive layer is formed on the inner coating surface by peeling the outer coating. The connection structure of the coated carbon fiber wire according to claim 1 or 2.