JP7251991B2 - TERMINAL, ELECTRIC WIRE WITH TERMINAL AND MANUFACTURING METHOD THEREOF - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal, an electric wire with a terminal, and a method for manufacturing the same, which are used in automobiles, for example.

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, and there is a risk of an increase in contact resistance, an increase in electrical resistance due to a decrease in wire diameter, and even a disconnection, which may lead to malfunction or stoppage of electrical components. be.

For this reason, a method has been proposed in which the connecting portion between the electric wire and the terminal is covered with a resin member. For example, an electric wire with a terminal has been proposed in which a conductor wire or the like exposed between a covering crimping portion and a conductor crimping portion is covered by applying a resin member (for example, Patent Literature 1 and Patent Literature 2).

Japanese Unexamined Patent Application Publication No. 2012-33378 JP 2017-183181 A

The crimp portion of a conventional open-barrel terminal undergoes large plastic deformation during crimping. However, even after being plastically deformed, springback occurs to some extent to restore the shape before deformation due to the elastic restoring force of the conductor and the terminal. Springback is a phenomenon in which a material returns to its original state when it is plastically deformed by sheet metal processing, press processing, etc. The springback increases as the tensile strength of materials such as high-strength steel and high-tensile strength increases, and the amount of plastic deformation increases. This phenomenon increases as .

When the shape of the terminal after crimping is restored to some extent due to such springback, the adhesion between the covered part of the covered conductor and the covered crimped part of the terminal decreases, and water leaks from the gap between the covered part and the covered crimped part. easier to penetrate.

As described above, the upper surface of the inter-barrel portion of the terminal is usually coated with a resin member such as an ultraviolet curable resin to cover the exposed conductor. Since it is difficult for the resin member to permeate the space between them, if water enters from the gap between the covering portion and the covering crimping portion, there is a risk that the water will penetrate to the conductor wire.

The present invention has been made in view of such problems, and an object of the present invention is to provide a terminal excellent in corrosion resistance, an electric wire with a terminal, and a method for manufacturing the same.

In order to achieve the above object, a first invention is an electric wire with a terminal in which a coated conductor and a terminal are connected, wherein the coated conductor comprises a coated portion and a conductive wire exposed from the tip of the coated portion. The terminal has a terminal body and a crimping portion, and the crimping portion includes a conductor crimping portion to which the conductor of the coated conductor is crimped, a coated crimping portion to which the coated portion of the coated conductor is crimped, The conducting wire crimping portion and the inter-barrel portion between the covering crimping portion are integrally formed, the conducting wire crimping portion is an open barrel, and the covering crimping portion is formed in a cylindrical shape before crimping and extends in the circumferential direction. The terminal is integrated, wherein a tip of the covering portion is located in the inter-barrel portion, and at least a portion where the conductor wire is exposed to the inter-barrel portion and the wire crimping portion is covered with a resin member. It is an attached electric wire.

It is desirable that the compressibility of the covered crimping portion is 50% or more and 70% or less.

It is preferable that the resin member contains at least one of ultraviolet curable resin, moisture curable resin and anaerobic curable resin.

It is desirable that the elongation of the resin member at -40°C is 100% or more.

According to the first aspect of the invention, since the conductor crimping portion is of the open barrel type, the conductor can be crimped with the same reliability as the conventional one. In addition, since the covering crimping part, which is integrated with the conductor crimping part through the barrel part, is integrated into a cylindrical shape, when crimping the covering part, compared to the conventional open barrel type covering crimping part Therefore, the amount of plastic deformation is small, and the springback can be reduced. Therefore, the adhesion between the coated portion of the coated conductor and the coated crimped portion of the terminal is high, and higher water stopping performance can be ensured.

In addition, if the compression rate of the covering crimping portion is 50% or more and 70% or less, the covering portion can be reliably crimped, and it is possible to suppress an increase in springback due to an excessively large amount of compression. can.

Moreover, if the resin member is at least one or more curable resins that are ultraviolet curable, moisture curable, or anaerobic curable, it can be cured in a short time. In particular, since the resin member has both UV-curing and moisture-curing properties, the resin member can be cured in a short period of time by a slight amount of moisture in the air or on the terminals, even in areas shaded by ultraviolet rays. .

In addition, if the elongation rate of the resin member at -40°C is 100% or more, the resin member is unlikely to crack even at low temperatures, and it is possible to ensure the thermal shock resistance required for automobiles and the like. .

A second invention is a method for manufacturing an electric wire with a terminal in which a coated conductor and a terminal are connected, wherein the coated conductor includes a coated portion and a conductive wire exposed from a tip of the coated portion, and the terminal has a terminal main body and a crimping portion, wherein the crimping portion includes a conductor crimping portion to which the conductor of the coated conductor is crimped, a coated crimping portion to which the coated portion of the coated conductor is crimped, and the conductor crimping portion. and the inter-barrel portion between the covering crimping portion is integrally configured, the conductor crimping portion is an open barrel, and the covering crimping portion is formed in a cylindrical shape before crimping and is integrated in the circumferential direction. , the tip of the covering portion is positioned in the inter-barrel portion, the covered conductor wire is arranged in the crimping portion, and the conductor wire is crimped by the conductor crimping portion; An electric wire with a terminal, wherein the covering portion is crimped at a compression ratio of 70% or less, and a resin member is applied and cured at least on the portion between the barrels and the conductor crimping portion where the conductor is exposed. is a manufacturing method.

According to the second invention, the lead wire crimping portion can be crimped with reliability similar to that of a conventional open barrel, and by forming the covered crimping portion in advance into a cylindrical shape, the amount of plastic deformation during crimping is can be reduced, and springback can be suppressed.

A third aspect of the invention is a terminal to be connected to a coated conductor, the terminal having a terminal body and a crimping portion, the crimping portion being a conductor crimping portion to which the conductor of the coated conductor is crimped; A covering crimping part to which the covering part of the covered conductor is crimped and a barrel-to-barrel part between the conductor crimping part and the covering crimping part are integrally configured, the conductor crimping part is an open barrel, and the covering The terminal is characterized in that the crimping portion is formed in a tubular shape before being crimped and is integrated in the circumferential direction , and the entire cylindrical covered crimping portion is formed with substantially the same diameter .

According to the third invention, the conductor crimping portion can be crimped with reliability similar to that of a conventional open barrel, and by forming the covered crimping portion in advance into a cylindrical shape, the amount of plastic deformation during crimping is can be reduced, and springback can be suppressed.

ADVANTAGE OF THE INVENTION According to this invention, the terminal excellent in corrosion resistance, the electric wire with a terminal, and its manufacturing method can be provided.

The perspective view which shows the electric wire 10 with a terminal. Sectional drawing which shows the electric wire 10 with a terminal. (a) is a cross-sectional view along the line AA in FIG. 2, and (b) is a cross-sectional view along the line BB in FIG. The figure which shows the state before crimping|crimping the terminal 1 and the covered conductor 11. FIG.

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. 3(a) is a cross-sectional view taken along the line AA of FIG. 2, and FIG. 3(b) is a cross-sectional view taken along the line BB of FIG. 1 is a perspective view of the resin member 17. As shown in FIG. A terminal-equipped electric wire 10 is configured by connecting a terminal 1 and a coated 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 wire 11 includes a covered portion 15 and the conductor wire 13 exposed from the tip thereof. The conducting wire 13 is, for example, a twisted wire in which a plurality of wires are twisted together.

Terminal 1 is made of copper or a 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. The transition portion 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, an insertion tab for a male terminal may be provided in place of the female terminal main body 3, or a bolt fastening portion such as a round terminal may be provided.

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. The portion 7 and the inter-barrel portion 8 between the covering crimping portion 9 are constructed integrally. The wire crimping portion 7 is an open barrel. The covering pressure-bonding portion 9 is formed by being rolled into a cylindrical body having a circular cross section, and by abutting the side edge portions thereof and joining them at the joint portion 19 to integrate them. That is, the covering pressure-bonding portion 9 is formed in a cylindrical shape and integrated in the circumferential direction.

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 conductor 13 exposed from the covering portion 15 is covered with the resin member 17 . That is, at least the portion where the conductor 13 is exposed from the inter-barrel portion 8 to the conductor crimping portion 7 is covered with the resin member 17 , and the conductor 13 is not exposed to the outside by the resin member 17 .

Let A0 be the cross-sectional area of the coated portion 15 before crimping in a cross section perpendicular to the axial direction of the coated conductor 11, and A1 be the cross-sectional area of the inside of the coated crimped portion 9 (coated portion 15) after crimping. , the compression rate of the covering pressure-bonding portion 9=A1/A0 is set to 50% or more and 70% or less. If the compressibility exceeds 70%, the crimping of the covering portion 15 is weak and there is a risk that the covering conductor 11 may come off from the terminal 1 . On the other hand, if the compressibility is less than 50%, the amount of plastic deformation of the coated crimping portion 9 during compression becomes large, resulting in large springback. When the compressibility is 50% or more and 60% or less, the adhesion between the covering crimping portion 9 and the covering portion 15 is further increased, and the water stoppage is improved, which is more preferable.

As the resin member 17, for example, a resin containing silicone acrylate, urethane acrylate, acrylic acrylate, or the like as a main component can be applied, and includes at least one or more ultraviolet-curing, moisture-curing, or anaerobic-curing curable resins. is desirable.

In particular, since the resin member 17 has both properties of both ultraviolet curing property and moisture curing property, the resin member 17 can be immediately cured by moisture on the surface of terminals or the like in the air even in areas where ultraviolet rays are difficult to reach. can be done. Furthermore, in addition to the hydrogen bonding between urethane and metal due to UV curing, the hydrolyzate of the alkoxy group of the silicon-modified acrylate in the moisture-curing part forms a strong covalent bond through a dehydration condensation reaction with the hydroxyl group on the surface of the terminal. It can be formed and can greatly contribute to the improvement of adhesion to metal.

In the resin member 17, for example, a soft segment is introduced into the polyol used for the oligomer, and the elongation at -40°C after curing is desirably 100% or more. When polyether urethane acrylate is used as the oligomer, polyols such as polypropylene glycol, polyethylene glycol, and polytetramethylene glycol can be used. An oligomer having a polytetramethylene glycol as an intermediate block and a hydroxy compound having an unsaturated double bond reactive to ultraviolet rays as a skeleton component, bound to the hydroxyl groups at both ends via an aromatic diisocyanate. is preferably used.

The oligomer used preferably has a weight-average molecular weight of 500 to 5,000, more preferably 2,000 to 5,000. Thereby, elongation at low temperature can be maintained, and thermal shock resistance can be ensured by doing so.

Next, a method for manufacturing the electric wire with terminal 10 will be described. FIG. 4 is a perspective view showing the terminal 1 and the coated conductor 11 before crimping. As described above, the terminal 1 has the terminal main body 3 and the crimping portion 5 , and the crimping portion 5 includes the conductor crimping portion 7 , the covering crimping portion 9 , and the space between the conductor crimping portion 7 and the covering crimping portion 9 . and the inter-barrel portion 8 are integrally formed.

The wire crimping portion of the terminal 1 has an open barrel shape with a substantially U-shaped cross section. On the other hand, the covering pressure-bonding portion 9 is formed in a cylindrical shape and integrated in the circumferential direction by a joint portion 19 . Note that the joint portion 19 is joined by laser welding, brazing, or the like, for example.

First, as shown in the figure, the covering portion 15 of a predetermined length at the tip of the covered conductor 11 is peeled off to expose the conductor 13 inside. Next, the tip of the covered conductor wire 11 is inserted from behind the covered crimping portion 9 , the exposed conductor wire 13 is positioned at the conductor crimping portion 7 , and the covering portion 15 is positioned at the covering crimping portion 9 . That is, the end portion of the covering portion 15 is positioned in the inter-barrel portion 8 .

In this manner, the covered conductor 11 is arranged in the crimping portion 5 , the conductor wire 13 is crimped by the conductor crimping portion 7 , and the covering portion 15 is crimped by the covering crimping portion 9 . At this time, the covering portion 15 is crimped in the covering crimping portion 9 with a compressibility of 50% or more and 70% or less. After that, the resin member 17 is applied to at least the portion where the conductor wire 13 is exposed from the inter-barrel portion 8 to the conductor wire crimping portion 7 and cured. The electric wire 10 with a terminal can be obtained by the above.

As described above, according to the present embodiment, the wire crimping portion 7 of the terminal 1 has a conventional open-barrel crimping configuration. Therefore, electrical reliability similar to that of a conventional open barrel type terminal can be ensured.

On the other hand, the covering crimping portion 9 of the terminal 1 is not of the usual open barrel type, but is integrated in a cylindrical shape in the circumferential direction. In other words, it does not have a substantially U-shaped open top before crimping. Therefore, when the covering pressure-bonding portion 9 is pressure-bonded to the covering portion 15, the amount of plastic deformation of the covering pressure-bonding portion 9 can be small. As a result, springback can be suppressed. By suppressing the springback, the shape of the terminal is less restored after crimping, so it is possible to prevent a decrease in adhesion between the coated portion 15 of the coated conductor wire 11 and the coated crimping portion 9 of the terminal 1. Intrusion of water through the gap between the portion 15 and the covering crimping portion 9 can be suppressed.

Incidentally, when the terminal 1 is manufactured, the coated pressure-bonding portion 9 is rolled into a cylindrical shape, and the circular portions are butted against each other and joined. For this reason, work strain is accumulated in the covering crimping portion 9, and after plastic working into a cylindrical shape, there is a possibility that a restoring force is generated due to the working. However, since the joints 19 are joined by brazing or laser welding, the processing strain is released to some extent by the heat at this time, and almost no restoring force accompanies the processing. Therefore, it is only necessary to consider the restoring force accompanying the plastic working when the covering portion 15 is crimped by the covering crimping portion 9, and springback can be suppressed.

Moreover, by setting the compressibility of the covering pressure-bonding portion 9 to 50% or more, the amount of plastic deformation of the covering pressure-bonding portion 9 does not become too large, and the occurrence of springback can be suppressed. Moreover, by setting the compressibility of the covering crimping portion 9 to 70% or less, the covering portion 15 can be reliably crimped by the covering crimping portion 9 .

In addition, since the resin member 17 has both UV-curing property and moisture-curing property, the resin member 17 can be cured in a short period of time by a small amount of moisture adhering to the air or the terminals, even in the areas shaded by the ultraviolet rays. can be made

Further, if the elongation rate of the resin member 17 at −40° C. is 100% or more, the resin member 17 is less likely to crack even at low temperatures, and it is possible to ensure thermal shock resistance.

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 body 5 Crimping portion 7 Wire crimping portion 8 Inter-barrel portion 9 Coating crimping portion 10 Wire with terminal 11 Coating Conducting wire 13 Conducting wire 15 Coating portion 17 Resin member 19 Joining portion

Claims (6)

An electric wire with a terminal in which a coated conductor and a terminal are connected,
The coated conductor includes a coated portion and a conductive wire exposed from the tip of the coated portion,
The terminal has a terminal body and a crimping portion,
The crimping portion is integrally composed of a conductor crimping portion to which the conductor is crimped, a covering crimping portion to which the covering portion is crimped, and an inter-barrel portion between the conductor crimping portion and the covering crimping portion. ,
The conductor crimping portion is an open barrel, and the coated crimping portion is formed into a cylindrical shape and integrated in the circumferential direction before crimping ,
A tip of the covering portion is positioned in the inter-barrel portion,
An electric wire with a terminal, wherein at least portions of the inter-barrel portion and the crimping portion where the conductor wire is exposed are covered with a resin member. 2. The electric wire with a terminal according to claim 1, wherein the compressibility of said covering crimping portion is 50% or more and 70% or less. 3. The electric wire with a terminal according to claim 1, wherein the resin member contains at least one of ultraviolet curable resin, moisture curable resin and anaerobic curable resin. The electric wire with a terminal according to any one of claims 1 to 3, wherein the elongation of the resin member at -40°C is 100% or more. A method for manufacturing an electric wire with a terminal in which a coated conductor and a terminal are connected,
The coated conductor includes a coated portion and a conductive wire exposed from the tip of the coated portion,
The terminal has a terminal body and a crimping portion,
The crimping portion is integrally composed of a conductor crimping portion to which the conductor is crimped, a covering crimping portion to which the covering portion is crimped, and an inter-barrel portion between the conductor crimping portion and the covering crimping portion. ,
The conductor crimping portion is an open barrel, and the coated crimping portion is formed into a cylindrical shape and integrated in the circumferential direction before crimping ,
Arranged so that the tip of the covering portion is located in the inter-barrel portion,
The coated conductor is arranged in the crimping part, the conductor is crimped by the conductor crimping part, and the coated part is crimped at a compression rate of 50% or more and 70% or less by the covering crimping part,
A method for manufacturing an electric wire with a terminal, characterized in that a resin member is applied to at least portions of the inter-barrel portion and the conductor crimping portion where the conductor wire is exposed, and the resin member is cured. A terminal connected to a coated conductor,
The terminal has a terminal body and a crimping portion,
The crimping portion includes a conductor crimping portion to which the conductor of the coated conductor is crimped, a covering crimping portion to which the covering portion of the covered conductor is crimped, and a barrel-to-barrel portion between the conductor crimping portion and the covering crimping portion. is composed of
The conductor crimping portion is an open barrel, and the coated crimping portion is formed into a cylindrical shape and integrated in the circumferential direction before crimping ,
A terminal characterized in that the entire cylindrical cover crimping portion is formed with substantially the same diameter .

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