JP2025040576A - Wire with terminal - Google Patents

Abstract

[Problem] To provide an electric wire with terminal that can obtain the required compression rate of the electric wire (core wire) with a small number of crimping operations. [Solution] An electric wire with terminal 1A includes an electric wire 10 configured by covering a conductive core wire 11 with an insulating coating, and a terminal 20 crimped to the electric wire 10. The terminal 20 has a terminal contact portion 21 formed at one end in the longitudinal direction of the terminal 20 and with which a mating terminal comes into contact, and a crimping portion 23 formed in a cylindrical shape at the other end in the longitudinal direction and to which the core wire 11 inserted therein is crimped. The crimping portion 23 is crimped into a square cylindrical shape with the core wire 11 inserted therein. A recess 30 extending along the longitudinal direction is formed on the outer periphery of the crimping portion 23, and the recess 30 has a plurality of divided recesses 31, 32 with different compression rates for the core wire 11. [Selected Figure] Figure 1

Description

The present invention relates to an electric wire with a terminal.

For example, terminals used in high-current circuits for electric vehicles require low crimping resistance to reduce heat generation at the crimping part, and the electric wire (core wire) needs to be sufficiently compressed at the crimping part. Closed barrel terminals, which are manufactured by cutting out the terminal contact part and crimping part, have been proposed as terminals for use in high-current circuits (see Patent Document 1).

JP 2000-21543 A

Such closed barrel terminals have high rigidity in the crimping portion, and if one tries to obtain the required compression ratio of the electric wire with one crimping, the terminal may crack. For this reason, the terminal described in Patent Document 1 is manufactured by rotating the terminal and the electric wire appropriately and crimping three times to obtain the required compression ratio of the electric wire, which increases the time required for crimping and leads to an increase in the manufacturing cost of the electric wire with terminal.

The present invention was made in consideration of the problems inherent in the conventional technology. The object of the present invention is to provide an electric wire with a terminal that can obtain the required compression ratio of the electric wire (core wire) with a small number of crimping operations.

The electric wire with terminal according to the present invention includes an electric wire formed by covering a conductive core wire with an insulating coating, and a terminal crimped to the electric wire. The terminal has a terminal contact portion formed at one longitudinal end of the terminal with which a mating terminal comes into contact, and a crimping portion formed in a cylindrical shape at the other longitudinal end to which the core wire inserted inside is crimped. The crimping portion is crimped into a square cylindrical shape with the core wire inserted therein, and a recess is formed on the outer periphery of the crimping portion that extends along the longitudinal direction, and the recess has multiple divided recesses with different compression rates for the core wire.

The present invention provides a terminal-attached electric wire that can achieve the required compression ratio of the electric wire (core wire) with a small number of crimping operations.

FIG. 1 is a perspective view illustrating an example of an electric wire with a terminal according to a first embodiment. 1 is a schematic cross-sectional view of a main part of an electric wire with a terminal according to a first embodiment. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. 3 is a cross-sectional view taken along line BB in FIG. 2. FIG. 2 is a schematic perspective view showing a terminal and an electric wire before crimping. 3 is a schematic cross-sectional view of a main portion showing a terminal and an electric wire before crimping. FIG. 4 is a schematic cross-sectional view of the main part showing a terminal and an electric wire in a crimped state. FIG. FIG. 11 is a perspective view showing an example of an electric wire with a terminal according to a second embodiment. FIG. 6 is a schematic cross-sectional view of a main part of an electric wire with a terminal according to a second embodiment. 10 is a cross-sectional view taken along line CC of FIG. 9. 10 is a cross-sectional view taken along line DD in FIG. 9. FIG. 2 is a schematic perspective view showing a terminal and an electric wire before crimping. 3 is a schematic cross-sectional view of a main portion showing a terminal and an electric wire before crimping. FIG. 4 is a schematic cross-sectional view of the main part showing a terminal and an electric wire in a crimped state. FIG.

The terminal-attached electric wire according to this embodiment will be described in detail below with reference to the drawings. Note that the dimensional ratios in the drawings have been exaggerated for the sake of explanation and may differ from the actual ratios.

[First embodiment]
The terminal-equipped electric wire 1A according to this embodiment is used in a large current circuit such as a charging connector for charging a battery of an electric vehicle or the like.

As shown in Figures 1 to 4, the terminal-attached electric wire 1A according to the first embodiment includes an electric wire 10 and a terminal 20 crimped to the electric wire 10. In the drawings, the arrow X indicates the longitudinal direction (axial direction) of the terminal-attached electric wire 1A and the terminal 20, and the arrow Y indicates the width direction (left-right direction) perpendicular to the longitudinal direction of the terminal-attached electric wire 1A and the terminal 20.

The electric wire 10 has a conductive core wire 11 and an insulating coating (not shown) that covers the core wire 11. The core wire 11 is composed of a bundle of multiple conductive metal strands made of a metal material such as copper. At the end of the electric wire 10, the insulating coating is removed to expose the core wire 11, and this exposed core wire 11 is crimped to the terminal 20.

The terminal 20 in this embodiment is a female terminal. The terminal 20 has a terminal contact portion 21 formed at one end in the axial direction X, which is in contact with and connected to a mating member (not shown) of a mating terminal (male terminal), and a crimping portion 23 formed in a hollow cylindrical shape at the other end in the axial direction X, to which the electric wire 10 (core wire 11) is crimped. This terminal 20 is also called a closed barrel terminal, and is manufactured by cutting out the outer periphery and interior of a solid metal round bar with a cutting tool such as a cutting tool so that it can withstand a large current capacity. Therefore, the terminal contact portion 21 and the crimping portion 23 are formed integrally.

The terminal contact portion 21 has a contact portion 22, which is in contact with the mating terminal for electrical connection. The terminal 20 of this embodiment also has an attachment portion 25 formed between the terminal contact portion 21 and the crimping portion 23, and a sealing member such as a rubber plug is attached to the attachment portion 25.

The crimping portion 23 has a cylindrical body 24A, which forms a closed end face 24a on the terminal contact portion 21 side in the axial direction X, and forms an open end face 24b on the side opposite the terminal contact portion 21 side in the axial direction X of the closed end face 24a (see FIG. 6). The core wire 11 of the electric wire 10 is inserted through the open end face 24b into the internal space of the crimping portion 23 (body 24A). Then, with the core wire 11 inserted, an external force is applied to the body 24A to tighten it, thereby deforming the body 24A and crimping the core wire 11 of the electric wire 10 to the terminal 20 (crimping portion 23).

Therefore, the electric wire 10 (core wire 11) is compressed at a predetermined compression ratio in the crimping section 23. In this embodiment, the "compression ratio" is calculated by (cross-sectional area after compression)/(cross-sectional area before compression). In other words, the compression ratio of the core wire is the value (%) obtained by dividing the cross-sectional area of the core wire in a direction perpendicular to the axial direction X after crimping by compression by the cross-sectional area of the core wire in a direction perpendicular to the axial direction X before crimping by compression. For example, a compression ratio of 70% means that the cross-sectional area of the electric wire 10 (core wire 11) in a direction perpendicular to the axial direction X has been reduced by 30% due to compression.

In this embodiment, the crimping portion 23 is crimped into a hexagonal tube shape with the core wire 11 inserted, and a recess 30 extending along the axial direction X is formed on the outer periphery of the crimping portion 23. In this embodiment, a pair of upper and lower recesses 30, 30 are formed on the outer periphery of the crimping portion 23, facing each other along a direction perpendicular to the axial direction X with the core wire 11 sandwiched therebetween (see FIG. 2).

The recess 30 has multiple divided recesses 31, 32 with different compression rates of the core wire 11. When multiple recesses 30 (divided recesses 31, 32) are provided, it is preferable to provide a step (height difference) between adjacent divided recesses 31, 32, for example. The width of the recess 30 (divided recesses 31, 32) in the left-right direction Y is approximately constant in the axial direction X.

In this embodiment, among the multiple division recesses 31, 32, the division recess 32 with the larger compression rate value (%) is formed on the terminal contact portion 21 side, and the division recess 31 with the smaller compression rate value (%) is formed on the opposite side to the terminal contact portion 21 side. It is preferable that the compression rate of the core wire 11 in the division recess 32 on the terminal contact portion 21 side, which has the larger compression rate value (%), is below 70%, that is, 70% or less. More specifically, it is preferable that the compression rate of the core wire 11 in the division recess 32 on the terminal contact portion 21 side, which has the larger compression rate value (%), is within the range of, for example, 70% to 50%. On the other hand, it is preferable that the compression rate of the core wire 11 in the division recess 31 on the opposite side to the terminal contact portion 21 side, which has the smaller compression rate value (%), is within the range of, for example, 60% to 40%. In addition, since the crimping portion 23 of the closed barrel terminal (terminal-attached electric wire 1A) used in a high-current circuit has high rigidity, it is preferable that the step (height difference) between adjacent divided recesses 31, 32 is not excessively large.

As shown in FIG. 5, the crimping portion 23 (tubular body 24A) is formed in a cylindrical shape before being crimped (before being crimped) to the electric wire 10 (core wire 11), and the crimping portion 23 (tubular body 24A) is crimped into a hexagonal tube shape using the crimping die 50A shown in FIG. 6 and FIG. 7.

As shown in FIG. 6, the crimping die 50A has a pair of upper and lower die bodies 51, 51 that are butted against each other, and each die body 51 has a protrusion (indent portion 52). The indent portion 52 has a plurality of divided indent portions 53, 54, and a step (height difference) is provided between adjacent divided indent portions 53, 54. When the pair of die bodies 51, 51 are closed (butted) so as to approach each other in the vertical direction (arrow direction), as shown in FIG. 7, the indent portion 52 (divided indent portions 53, 54) compresses (presses) the core wire 11 of the electric wire 10 and the crimping portion 23 of the terminal 20. As a result, a recess 30 is formed on the outer periphery of the crimping portion 23, which has a plurality of divided recesses 31, 32 with different compression rates for the core wire 11.

By providing a step (height difference) in the protrusion (indentation 52) of the crimping die 50A, the number of areas where the core wire 11 stretches when the electric wire 10 and the terminal 20 are crimped can be increased, thereby increasing the contact path (conductivity path) between the terminal 20 and the core wire 11.

Thus, the electric wire with terminal 1A according to this embodiment includes an electric wire 10 formed by covering a conductive core wire 11 with an insulating coating, and a terminal 20 crimped to the electric wire 10. The terminal 20 has a terminal contact portion 21 formed at one end in the longitudinal direction (axial direction X) of the terminal 20 and contacting a mating terminal, and a crimping portion 23 formed in a cylindrical shape at the other end in the longitudinal direction (axial direction X) and crimping the core wire 11 inserted therein. The crimping portion 23 is crimped into a square cylindrical shape with the core wire 11 inserted therein. A recess 30 extending along the longitudinal direction (axial direction X) is formed on the outer periphery of the crimping portion 23, and the recess 30 has a plurality of divided recesses 31, 32 with different compression rates for the core wire 11.

By providing a step (height difference) in the recess 30 on the outer periphery of the crimping portion 23 and changing the compression ratio for each divided recess 31, 32, the elongation of the core wire 11 changes depending on the crimping point, and the contact path (contact area) in the elongation direction (axial direction X) of the core wire 11 can be increased. Since it is possible to give a large deformation to the crimping portion 23, the required compression ratio of the electric wire 10 (core wire 11) can be obtained with one crimping. Therefore, the number of crimping times can be reduced to one, and the manufacturing cost can be reduced by reducing the time required for crimping. In addition, the electrical resistance of the crimping portion 23 can be reduced by increasing the contact area not only between the terminal 20 and the electric wire 10 but also between the core wires 11 (multiple metal wires).

As described above, according to this embodiment, it is possible to provide a terminal-attached electric wire 1A that can obtain the required compression ratio of the electric wire 10 (core wire 11) with a single crimping operation.

In the electric wire with terminal 1A, the crimping portion 23 is crimped into a hexagonal tube shape, and a pair of recesses 30, 30 may be formed on the outer periphery of the crimping portion 23, facing each other along a direction perpendicular to the longitudinal direction (axial direction X) with the core wire 11 sandwiched therebetween.

Since it becomes possible to impart a larger deformation to the crimping portion 23, it is possible to increase the contact path (contact area) in the elongation direction (axial direction X) of the core wire 11. In addition, a pair of recesses 30, 30 facing each other along a direction perpendicular to the longitudinal direction (axial direction X) with the core wire 11 in between can be formed on the outer periphery of the crimping portion 23 in a single crimping operation (see Figures 6 and 7), making it possible to reduce manufacturing costs by reducing the time required for crimping.

In the terminal-equipped electric wire 1A, the compression ratio, which is the value obtained by dividing the cross-sectional area of the core wire in a direction perpendicular to the longitudinal direction (axial direction X) after crimping in the divided recesses 31 and 32 by the cross-sectional area of the core wire in a direction perpendicular to the longitudinal direction (axial direction X) before crimping, may be 70% or less.

By forming the recess 30 (split recesses 31, 32) in this manner, it is possible to impart large deformation to the crimping portion 23 while preventing breakage of the core wire 11 when the electric wire 10 and the terminal 20 are crimped together.

Second Embodiment
Next, an electric wire with terminal 1B according to a second embodiment will be described. Note that components that are substantially the same as those in the electric wire with terminal 1A described above are given the same reference numerals, and descriptions thereof will be omitted.

8 to 11, in this embodiment, among the multiple divided recesses 31, 32, the divided recesses 32 with the larger compression ratio value (%) are formed on the opposite side to the terminal contact portion 21 side, and the divided recesses 32 with the smaller compression ratio value (%) are formed on the terminal contact portion 21 side. It is preferable that the compression ratio of the core wire 11 in the divided recesses 32 on the opposite side to the terminal contact portion 21 side, which has the larger compression ratio value (%), is below 70%, that is, 70% or less. More specifically, it is preferable that the compression ratio of the core wire 11 in the divided recesses 32 on the opposite side to the terminal contact portion 21 side, which has the larger compression ratio value (%), is within the range of, for example, 70% to 50%. On the other hand, it is preferable that the compression ratio of the core wire 11 in the divided recesses 31 on the terminal contact portion 21 side, which has the smaller compression ratio value (%), is within the range of, for example, 60% to 40%. In addition, since the crimping portion 23 of the closed barrel terminal (terminal-attached electric wire 1B) used in a high-current circuit has high rigidity, it is preferable that the step (height difference) between adjacent divided recesses 31, 32 is not excessively large.

As shown in FIG. 12, the crimping portion 23 (tubular body 24B) is formed in a cylindrical shape before being crimped (before being crimped) to the electric wire 10 (core wire 11), and the crimping portion 23 (tubular body 24B) is crimped into a hexagonal tube shape using the crimping die 50B shown in FIG. 13 and FIG. 14.

As shown in FIG. 13, the crimping die 50B has a pair of upper and lower die bodies 51, 51 that are butted against each other, and each die body 51 has a protrusion (indent portion 52). The indent portion 52 has a plurality of divided indent portions 53, 54, and a step (height difference) is provided between adjacent divided indent portions 53, 54. When the pair of die bodies 51, 51 are closed (butted) so as to approach each other in the vertical direction (arrow direction), as shown in FIG. 14, the indent portion 52 (divided indent portions 53, 54) compresses (presses) the core wire 11 of the electric wire 10 and the crimping portion 23 of the terminal 20. As a result, a recess 30 is formed on the outer periphery of the crimping portion 23, which has a plurality of divided recesses 31, 32 with different compression rates for the core wire 11.

According to the electric wire with terminal 1B of this embodiment, like the electric wire with terminal 1A described above, it is possible to provide an electric wire with terminal 1B that can obtain the required compression ratio of the electric wire 10 (core wire 11) with a single crimping operation.

Although the present embodiment has been described above, the present embodiment is not limited to these, and various modifications are possible within the scope of the gist of the present embodiment.

1A, 1B Electric wire with terminal 10 Electric wire 11 Core wire 20 Terminal 21 Terminal contact portion 23 Crimping portion 30 Recess 31 Dividing recess 32 Dividing recess

Claims (3)

An electric wire formed by covering a conductive core wire with an insulating coating;
a terminal crimped to the electric wire,
The terminal is
a terminal contact portion formed at one end of the terminal in a longitudinal direction and adapted to come into contact with a mating terminal;
a crimping portion formed in a cylindrical shape at the other end in the longitudinal direction and into which the core wire inserted therein is crimped,
The crimping portion is crimped into a rectangular tube shape with the core wire inserted therein,
A recess extending along the longitudinal direction is formed on the outer periphery of the crimping portion,
The recess has a plurality of divided recesses each having a different compression ratio of the core wire.
Wire with terminal. The electric wire with terminal according to claim 1, wherein the crimping portion is crimped into a hexagonal tube shape, and a pair of the recesses are formed on the outer periphery of the crimping portion, facing each other along a direction perpendicular to the longitudinal direction with the core wire sandwiched therebetween. 3. The electric wire with terminal according to claim 1, wherein a compression ratio, which is a value obtained by dividing a cross-sectional area of the core wire in a direction perpendicular to the longitudinal direction after crimping in the dividing recess by a cross-sectional area of the core wire in the direction perpendicular to the longitudinal direction before crimping, is 70% or less.

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