JP2022118198A - Terminal-equipped wire and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a terminal-equipped wire capable of securely covering a conductive wire exposed from a conductive wire crimping portion with an anticorrosion material without impairing manufacturability and ensuring corrosion resistance.

SOLUTION: A first anticorrosion material 17a is applied to a protruding portion of a conductive wire 13 exposed from the tip of a conductive wire crimping portion 7 by, for example, a dispenser or the like (first anticorrosion material application step). At this time, the first anticorrosion material 17a is applied so as to avoid the conductive wire crimping portion 7. After the first anticorrosion material application step, the first anticorrosion material 17a in front of the protruding portion of the conductive wire 13 is temporarily hardened to form a temporary hardened portion 18 (anticorrosion material temporary hardening step). Thereafter, the first anticorrosion material 17a applied in the first anticorrosion material application step is made to penetrate into the vicinity of the tip of the conductive wire 13 (anticorrosion material permeation step). At this time, the first anticorrosion material 17a penetrates between the strands of the conductive wire 13 and a gap 12 between the conductive wire 13 and the tip of the conductor crimping portion 7.

SELECTED DRAWING: Figure 3

COPYRIGHT: (C)2022,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a terminal-equipped electric wire for use in automobiles, etc., and a method for manufacturing the same.

2. Description of the Related Art Conventionally, in the fields of automobiles, OA equipment, home electric appliances, and the like, electric wires made of copper-based materials with excellent electrical conductivity have been used as power lines and signal lines. In particular, in the field of automobiles, the performance and functionality of vehicles are rapidly advancing, and the number of various electric devices and control devices to be mounted on vehicles is increasing. Therefore, along with this, the number of electric wires with terminals used tends to increase.

On the other hand, while environmental problems are attracting attention, there is a demand for weight reduction of automobiles. Therefore, an increase in weight due to an increase in the amount of use of the wire harness becomes a problem. For this reason, light weight aluminum wires have attracted attention in place of conventionally used copper wires.

Here, a connection terminal is used when connecting such electric wires or at a connection portion of equipment. However, even in an electric wire with a terminal using an aluminum electric wire, there are cases where copper, which has excellent electrical properties, is used for the terminal portion for the reliability of the connecting portion. In such a case, an aluminum electric wire and a copper terminal are joined and used.

However, when dissimilar metals are brought into contact with each other, so-called electrolytic corrosion may occur due to the difference in standard electrode potential. In particular, since the standard electrode potential difference between aluminum and copper is large, corrosion on the electrically base aluminum side progresses due to the influence of water splashing and condensation on the contact portion. As a result, the connection between the wire and the terminal at the connection part becomes unstable, increasing the electrical resistance due to an increase in contact resistance and a decrease in the wire diameter. be. For this reason, a method has been proposed in which the connecting portion between the electric wire and the terminal is coated with an anticorrosion material.

For example, by lowering the viscosity of the anti-corrosion material, the anti-corrosion material is applied in the manufacturing process by heating the resin to temporarily lower the viscosity, in order to allow the anti-corrosion material to efficiently penetrate between the strands of the conductor wire. A method has been proposed (Patent Document 1).

JP 2016-225171 A

FIG. 5A is a conceptual diagram showing a state in which the conductor wire 113 is crimped in the conductor crimping portion 107. FIG. When the conductor wire crimping portion 107 is compressed with a mold and the conductor wire 113 is crimped, a gap 101 may be generated between the tip portion and the conductor wire 113 .

In this state, as shown in FIG. 5(b), when the anti-corrosion 117 is applied so as to cover the conductor wire 113 exposed from the tip of the conductor crimping portion 107, the inventors found that as shown in FIG. 5(c), It has been found that the gap 101 and the air remaining between the strands of the conductor wire 113 may generate air bubbles 102 . When such air bubbles 102 are generated, the thickness of the anti-corrosion 117 at this portion is reduced, and there is a risk that the anti-corrosion 117 may burst during hardening or the like, exposing the conducting wire 113 . Therefore, there is a problem that the anticorrosion property is lowered.

On the other hand, as in Patent Document 1, there is a method of making the anti-corrosion material have a low viscosity to make it easier for air bubbles to escape. Equipment is required, and the manufacturing process is lengthened, resulting in an increase in cost.

The present invention has been made in view of such problems, and an electric wire with a terminal that can reliably cover the conductor exposed from the crimped portion of the conductor with an anti-corrosion property without impairing the manufacturability. and a manufacturing method thereof.

In order to achieve the above object, a first invention provides an electric wire with a terminal to which a covered conductor and a terminal are connected, wherein the conductor exposed portion obtained by removing the covering at the tip of the covered conductor is the conductor of the terminal. and at least one of a first anti-corrosion protection provided so as to avoid the lead wire crimping part with respect to a protrusion portion of the conductor which is crimped by the crimping part and exposed from the tip of the lead wire crimping part. and a second anti-corrosion layer provided so as to cover a portion, wherein the first anti-corrosion layer permeates a gap between the conductor wire and the conductor crimping portion. .

It further has a third anti-corrosion part provided so as to cover at least a part of the crimped part of the conductor wire, the second anti-corrosion part being a portion other than the protruding margin part of the conductor wire, wherein the second anti-corrosion part comprises the first anti-corrosion part and the It may be provided so as to cover at least part of the third anticorrosion.

A second invention is a method for manufacturing an electric wire with a terminal in which a covered conductor and a terminal are connected, the electric wire processing step of removing the covering portion of the tip portion of the covered conductor to form an exposed conductor portion;
A wire/terminal connecting step of crimping the exposed conductor portion with a conductor crimping portion of a terminal to connect the conductor and the terminal; A first anti-corrosion coating step of applying anti-corrosion so as to avoid the crimped portion of the conductor, a third anti-corrosion coating step of applying a third anti-corrosion to the rear end side of the crimped portion of the conductor, and the first anti-corrosion coating. Anticorrosion penetrating step for penetrating the anticorrosion coating applied in the step to the vicinity of the tip of the conductor wire; a second anti-corrosion coating step of further coating the anti-corrosion so as to cover at least a part of the anti-corrosion applied in the food coating step; and a resin curing step of curing the applied anti-corrosion, wherein the anti-corrosion In the permeation step, the anticorrosion applied in the first anticorrosion application step is permeated into the gap between the conductor wire and the tip portion of the conductor crimped portion for a predetermined permeation time, and in the third anticorrosion application step, The method of manufacturing an electric wire with a terminal is characterized in that the coated anti-corrosion material is allowed to permeate into a gap between the conductive wire and the rear end portion of the crimped portion of the conductive wire.

According to the first and second inventions, since the anti-corrosion material is applied to the protruded portion of the conductor exposed from the tip of the conductor crimping part so as to avoid the conductor crimping part, a gap between the conductor and the conductor crimping part is formed. Not covered with anti-corrosion material. In addition, by infiltrating the anti-corrosion material between the strands of the conducting wire, it is possible to fill the spaces between the strands of the conducting wire and gaps with the anti-corrosion material, thereby suppressing the formation of air bubbles. Therefore, it is possible to suppress the deterioration of the anticorrosiveness caused by the air bubbles.

In addition, while the anti-corrosion material is infiltrated, the anti-corrosion material is applied so as to cover the crimped portion of the conductive wire other than the protruding portion of the conductor, thereby shortening the application time of the anti-corrosion material. can.

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide an electric wire with a terminal and a method for manufacturing the same, which can reliably cover the conductor exposed from the conductor crimping part with an anticorrosive and ensure anticorrosion without impairing manufacturability. .

The perspective view which shows the electric wire 10 with a terminal. Sectional drawing which shows the electric wire 10 with a terminal. 4(a) to 4(c) are cross-sectional enlarged views showing a step of applying a first anti-corrosion layer 17a; (a), (b) is sectional drawing which shows the method of apply|coating the 2nd anti-corrosion 17b and the 3rd anti-corrosion 17c. 4(a) to 4(c) are diagrams showing a conventional process of applying anti-corrosion material 117 to a crimped portion 107 of a conductor wire.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an electric wire 10 with a terminal, and FIG. 2 is a cross-sectional view. In addition, FIG. 1 is a perspective view of the anticorrosion 17 . The anti-corrosion 17 is a general term for the first anti-corrosion 17a, the second anti-corrosion 17b, and the third anti-corrosion 17c, which will be described later. An electric wire 10 with a terminal is configured by connecting a terminal 1 and a covered conductor 11 .

Covered lead wire 11 includes lead wire 13 made of aluminum or an aluminum alloy and cover portion 15 covering lead wire 13 . That is, the covered conductor 11 has a covered portion 15 and the conductor 13 exposed from the tip thereof. The conducting wire 13 is, for example, a twisted wire in which a plurality of strands are twisted together.

The terminal 1 is of open barrel type and made of copper or copper alloy. A coated conductor 11 is connected to the terminal 1 . The terminal 1 is configured by connecting a terminal main body 3 and a crimping portion 5 via a transition portion 4 . The transition portion 4 positioned between the crimping portion 5 and the terminal body 3 is open at the top.

The terminal main body 3 is formed by forming a plate-shaped material having a predetermined shape into a tubular body having a rectangular cross section. The terminal body 3 has an elastic contact piece inside which is formed by folding a plate-like material into a rectangular cylindrical body. The terminal body 3 is connected by inserting a male terminal or the like from the front end portion. In the following description, an example in which the terminal body 3 is a female terminal that allows insertion of an insertion tab (not shown) of a male terminal or the like will be shown. is not particularly limited. For example, instead of the female terminal main body 3, for example, an insertion tab for a male terminal may be provided. Further, the terminal body 3 may be a general round terminal or a tip-open terminal instead of a male-female fitting type.

The crimping part 5 is a part to be crimped with the coated conductor 11, and has a substantially U-shaped cross-sectional shape perpendicular to the longitudinal direction of the terminal 1 before crimping. The crimping portion 5 of the terminal 1 includes a conductor crimping portion 7 for crimping the conductor wire 13 exposed from the covering portion 15 to the distal end side of the covered conductor 11, a covering crimping portion 9 for crimping the covering portion 15 of the covered conductor 11, and a conductor crimping portion. It consists of an inter-barrel portion 8 between the portion 7 and the covering crimp portion 9 .

A portion of the inner surface of the conductor crimping portion 7 is provided with serrations (not shown) in the width direction (direction perpendicular to the longitudinal direction). By forming the serrations in this manner, the oxide film on the surface of the conductor 13 is easily destroyed when the conductor 13 is crimped, and the contact area with the conductor 13 can be increased.

At the tip of the covered conductor 11, the covering portion 15 is peeled off, and the conductor 13 inside is exposed. The covering portion 15 of the covered conductor wire 11 is crimped by the covering crimping portion 9 of the terminal 1 . Further, the conductor wire 13 exposed by peeling off the covering portion 15 is crimped by the conductor crimping portion 7 . The conductor wire 13 and the terminal 1 are electrically connected at the conductor crimping portion 7 . The end face of the covering portion 15 is located in the inter-barrel portion 8 between the covering crimping portion 9 and the conductor crimping portion 7 .

In the present invention, at least the portion from the inter-barrel portion 8 to the portion where the conductor wire 13 at the tip of the conductor crimping portion 7 is exposed is covered with the anti-corrosion layer 17 . Therefore, the conductive wire 13 is not exposed to the outside due to the anticorrosion 17 . The anti-corrosion material 17 is, for example, an acrylate-based photo-curing resin.

Next, a method for manufacturing the electric wire with terminal 10 will be described. First, the covering portion 15 of the tip portion of the covering conductor 11 is removed to form the conductor exposed portion (electric wire processing step). Next, the exposed wire portion is crimped by the wire crimping portion 7 of the terminal 1 to connect the wire 13 and the terminal 1 (wire/terminal connecting step).

Next, as shown in FIG. 3(a), a first anti-corrosion material 17a is applied by, for example, a dispenser to the protruding portion of the conductor 13 exposed from the tip of the conductor crimping portion 7 toward the terminal body 3 ( first anti-corrosion coating step). At this time, the first anti-corrosion layer 17 a is applied so as to avoid the wire crimping portion 7 . That is, the first anti-corrosion layer 17 a is applied to the upper surface of the leading end portion of the wire crimping portion 7 so as to contact only the protruded portion of the lead wire 13 without adhering to the first anti-corrosion layer 17 a.

After the first anti-corrosion coating step, as shown in FIG. 3B, the first anti-corrosion portion 17a in front of the protruding portion of the conductor 13 is partially pre-cured to form a pre-cured portion 18 (pre-hardening portion 18). material temporary hardening process). The temporary hardened portion 18 can be formed by partially irradiating a portion of the first anticorrosion 17a on the terminal main body 3 side with light. In addition, the temporary hardening part 18 may be completely hardened or may not be completely hardened. In any case, the fluidity should remain in the portion of the first anti-corrosion material 17a adhering to the conducting wire 13 .

Further, the anticorrosion temporary hardening step may be performed as necessary, and is not necessary when the first anticorrosion 17a flows into the terminal main body 3 in a small amount in the anticorrosion permeation step to be described later. For example, when the viscosity of the first anticorrosion 17a when applied is 1000 mPa·s or less, it is effective to perform the anticorrosion temporary hardening step.

After that, as shown in FIG. 3(c), the first anticorrosion 17a applied in the first anticorrosion coating step is allowed to permeate the vicinity of the tip portion of the lead wire 13 (anticorrosion permeation step). At this time, the first anti-corrosion material 17 a penetrates into the gaps 12 between the strands of the conductor wire 13 and between the conductor wire 13 and the tip of the conductor crimping portion 7 . The permeation time is desirably 0.3 to 2.4 seconds, more desirably 1 to 2.4 seconds. If the permeation time is not enough, air bubbles are generated without filling the gaps 12, and if the permeation time is too long, the cycle time becomes too long and the productivity deteriorates.

In the anti-corrosion penetration step, after the first anti-corrosion 17a is permeated into the protruding portion of the conductor 13, the second anti-corrosion is applied so as to cover the first anti-corrosion 17a (second anti-corrosion coating step). , ensure a sufficient anti-corrosion thickness at the leading end of the wire crimping portion 7; In this case, the second anti-corrosion resin may be made of a resin having the same viscosity as that of the first anti-corrosion layer 17a, or may be a resin having a higher viscosity than that of the first anti-corrosion layer 17a.

As described above, the second anticorrosion agent cannot be applied until the permeation step of the anticorrosion agent is completed. For this reason, as shown in FIG. 4( a ), in parallel with the anti-corrosion permeation step, a portion other than the protruded portion of the conductor 13 , so as to cover the conductor crimping portion 7 from the inter-barrel portion 8 . 3 Anticorrosion 17c may be applied (third anticorrosion application step). By doing so, it is possible to effectively utilize the waiting time in the anticorrosion permeation step to apply the anticorrosion to other parts.

In this case, as shown in FIG. 4(b), after the third anti-corrosion layer 17c has been applied and the step of penetrating the anti-corrosion layer is completed, the second anti-corrosion layer 17b is applied to the vicinity of the tip portion of the lead wire crimping portion 7. to ensure the thickness of the anti-corrosion 17 near the tip of the wire crimping portion 7 .

Finally, the applied anticorrosion 17 (the first anticorrosion 17a, the second anticorrosion 17b, and the third anticorrosion 17c) is irradiated with light to be completely cured (resin curing step). The electric wire 10 with a terminal can be obtained by the above.

In the present invention, the application of the anticorrosion 17 means a method of bringing droplets of the anticorrosion 17 into contact with the target area, or ejecting (dripping) droplets of the anticorrosion 17 from the supply unit and adhering to the target area. It includes all methods for obtaining a state in which the anti-corrosion 17 is adhered to the target portion, such as a method for For example, droplets of the anti-corrosion 17 may be applied to the target area by contacting them with a mechanical dispenser, or may be applied by ejecting them from a supply unit with a jet dispenser.

Also, the anti-corrosion 17 may be applied at a plurality of locations instead of at one location in each step. For example, in the first anti-corrosion coating step, the first anti-corrosion coating 17 a may be applied to a plurality of locations so as not to cover the upper portion of the wire crimping portion 7 but to cover the tip of the lead wire 13 .

Since the first anti-corrosion layer 17a, the second anti-corrosion layer 17b, and the third anti-corrosion layer 17c are formed at different timings, their boundaries can be identified with an optical microscope or a polarizing microscope after cross-sectional polishing.

As described above, according to the present embodiment, since the first anti-corrosion layer 17 a is applied so as not to cover the upper portion of the wire crimping portion 7 , the air accumulated in the gap 12 between the wire crimping portion 7 and the wire 13 is applied. It is possible to suppress the generation of air bubbles. In addition, since sufficient penetration time is ensured before applying the second anti-corrosion layer 17b, it is possible to suppress the generation of air bubbles when the second anti-corrosion layer 17b is applied, and the lead wires are crimped by the second anti-corrosion layer 17b. The thickness of the anticorrosion 17 near the tip of the portion 7 can be ensured.

Such an effect is particularly effective when the wire diameter is small. For example, in the case of an electric wire of 0.3 sq to 2.5 sq, it is difficult for the resin to permeate the gap 12 and it is difficult for air bubbles to escape.

Further, after the first anticorrosion coating step, the first anticorrosion 17a is temporarily hardened, so that the first anticorrosion 17a flows toward the terminal main body 3, and the first anticorrosion 17a is sufficiently moved toward the conductor 13. It is possible to suppress the impossibility of infiltration.

By applying the third anti-corrosion layer 17c in parallel with the anti-corrosion permeation step, the permeation time can be effectively used and the tact time can be shortened.

Various types of electric wires with terminals were manufactured by adjusting conditions such as permeation time and viscosity of anticorrosion, and various evaluations were performed. An ultraviolet curable acrylate resin was used as the anti-corrosion material. Perform the first anticorrosion coating process → second anticorrosion coating process → resin curing process, check the permeability after curing (whether or not there are bubbles) and the appearance of the film thickness, and the resin film thickness of the conductor part is 50 μm or more. Those with . Also, the time required for manufacturing was evaluated.

For each condition, 10 samples were prepared and evaluated as described above. At this time, ◯ indicates that all 10 samples cleared the criteria, Δ indicates that the number of acceptable samples was 1 to 9, and x indicates that all failed samples. All of the permeability, film thickness and target takt time were evaluated, and the lowest evaluation was shown in Table 1 as the evaluation of the conditions.

If the permeation time was set to 2.5 seconds or longer, the target tact time was exceeded, and all were rejected. On the other hand, when the permeation time was 0.1 second, the resin did not permeate sufficiently and air bubbles were observed. Therefore, it is desirable that the permeation time is 0.3 to 2.4 seconds.

In addition, depending on the viscosity, insufficient film thickness was observed by lengthening the permeation time. To solve this problem, the lack of film thickness was resolved by adding a temporary hardening step for the first anti-corrosion layer.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not influenced by the above-described embodiments. It is obvious that a person skilled in the art can conceive various modifications or modifications within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. be understood to belong to

1 Terminal 3 Terminal main body 4 Transition portion 5 Crimping portion 7 Lead wire crimping portion 8 Inter-barrel portion 9 Insulated crimping portion 10 With terminal Electric wire 11 Covered conductor wire 12 Gap 13 Conductor wire 15 Covered portion 17 Anti-corrosion part 17 a First anti-corrosion part 17 b Second anti-corrosion part 17 c Second 2 Anti-corrosion part 18 Temporary hardening part 101 Gap 102 Air bubble 107 Lead wire crimping part 113 Lead wire 117 Anti-corrosion part

Claims (3)

An electric wire with a terminal in which a coated conductor and a terminal are connected,
The conductor exposed portion from which the covering portion of the tip portion of the covered conductor is removed is crimped by the conductor crimping portion of the terminal,
a first anti-corrosion material provided so as to avoid the conductor crimping portion with respect to the protrusion portion of the conductor exposed from the tip of the conductor crimping portion;
a second anticorrosion provided to cover at least a portion of the first anticorrosion;
and
An electric wire with a terminal, wherein the first anti-corrosion material permeates a gap between the conductor wire and the conductor crimping portion. further comprising a third anti-corrosion material provided so as to cover at least a portion of the conductor crimping portion at a portion other than the protrusion portion of the conductor;
2. The electric wire with a terminal according to claim 1, wherein said second anticorrosive material is provided so as to cover at least part of said first anticorrosive material and said third anticorrosive material. A method for manufacturing an electric wire with a terminal in which a coated conductor and a terminal are connected,
A wire processing step of removing the covering of the tip of the covered conductor to form an exposed conductor;
A wire/terminal connection step of crimping the exposed conductor portion with a conductor crimping portion of a terminal to connect the conductor wire and the terminal;
a first anti-corrosion coating step of applying an anti-corrosion material to the projection portion of the conductor exposed from the tip of the crimped conductor so as to avoid the crimped conductor;
a third anticorrosion applying step of applying a third anticorrosion to the rear end side of the conductor crimping portion;
an anticorrosion impregnation step of penetrating the anticorrosion applied in the first anticorrosion coating step into the vicinity of the tip of the conductor;
After infiltrating the anticorrosion into the protruding portion of the conductor, the anticorrosion is further applied so as to cover at least a part of the anticorrosion applied in the first anticorrosion application step and the third anticorrosion application step. 2 anti-corrosion coating step;
a resin curing step of curing the applied anticorrosion;
and
In the anti-corrosion permeation step, the anti-corrosion coating applied in the first anti-corrosion coating step is permeated into the gap between the conductor wire and the tip portion of the crimped portion of the conductor wire for a predetermined permeation time, and the third anti-corrosion insulation step is performed. A method for manufacturing an electric wire with a terminal, wherein the anticorrosive material applied in the coating step is allowed to permeate into a gap between the conductor wire and the rear end portion of the crimped portion of the conductor wire.

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