JP7479277B2 - Electric wire with terminal and method for manufacturing the same - Google Patents

Description

The present invention relates to an electric wire with a terminal and a method for manufacturing an electric wire with a terminal.

Conventionally, a wire with terminal is known that has a terminal at the end of a coated electric wire. In general, a coated electric wire is composed of a wire conductor portion made of a single or multiple strands, and an insulating coating portion made of insulating resin that coats the wire conductor portion. In such a coated electric wire, the end portion of the wire conductor portion is exposed by removing a part of the insulating coating portion. A wire with terminal is manufactured by joining the exposed end portion of the wire conductor portion (exposed conductor portion) and the end portion of the insulating coating portion including the removed portion (tip of coating) to a terminal.

For example, Patent Document 1 discloses an electric wire with a terminal in which the exposed conductor portion of the end portion of a flat electric wire, which is a flat coated electric wire, is crimped to a terminal by a wire barrel, and the tip of the coating is crimped to the terminal by an insulation barrel. Patent Document 2 discloses an electric wire with a terminal in which the spacing between the wire barrel pieces is made longer than the width dimension of the exposed conductor portion of the flat electric wire, so that the exposed conductor portion can be crimped reliably by the wire barrel pieces, and the spacing between the insulation barrel pieces is made longer than the width dimension of the insulating coating portion, so that the insulating coating portion can be crimped reliably by the insulation barrel pieces.

Such electric wires with terminals are used, for example, in wire harnesses mounted on vehicles. In recent years, in the field of automobiles and other vehicles, there has been rapid progress in electrification, as typified by hybrid cars and electric cars, and in multi-functionality or high functionality, as typified by autonomous driving systems and connected cars. For this reason, there is a trend toward using electric wires with terminals capable of carrying large currents in vehicle wire harnesses.

JP 2011-124135 A JP 2011-14283 A

In a wide variety of applications, including the above-mentioned vehicle wire harnesses, thick or flat wires are often used as the insulated wire for electric wires with terminals that can carry large currents. For the insulating coating of such insulated electric wires, for example, crystalline resins such as polyethylene and cross-linked polyethylene are used. In general, crystalline resins have a larger molding shrinkage rate than non-crystalline resins, but have excellent heat resistance and chemical resistance, and therefore tend to be used as materials for the insulating coating of electric wires with terminals that can carry large currents, from the viewpoint of obtaining high reliability. Such insulating coatings are formed to cover the electric wire conductors, for example, by extrusion molding of the crystalline resin.

On the other hand, the insulating coating made of crystalline resin shrinks after molding due to residual stress during extrusion molding and thermal strain caused by cooling of the molding die. However, in the conventional electric wire with terminal described above, the insulating coating is crimped and joined to the terminal by restraining the tip of the insulating coating at the end of the coated electric wire with the insulation barrel. For this reason, the insulating coating shrinks while restrained by the insulation barrel, and as a result, there is a risk that the insulating coating will break away from the insulation barrel and become detached from the terminal. Alternatively, stress concentration occurs between the part of the insulating coating that is restrained by the insulation barrel and the part that is not restrained, which may cause the insulating coating to break.

In particular, when the coated electric wire of the terminal-attached electric wire is a thick electric wire or a flat electric wire, the amount of crystalline resin used to mold the insulating coating is large, so the residual stress and thermal strain generated in the insulating coating during extrusion molding become large, and as a result, the shrinkage of the insulating coating after molding becomes significant. In particular, in the case of a flat electric wire, the pressure during extrusion molding is concentrated on the long side of the flat cross section, so the shrinkage of the insulating coating after molding described above becomes more significant, and the detachment and breakage of the insulating coating due to this shrinkage also become more significant.

The present invention has been made in consideration of the above, and aims to provide an electric wire with a terminal and a method for manufacturing an electric wire with a terminal that can prevent the insulating coating from coming off the terminal and the insulating coating from being damaged.

In order to solve the above problems and achieve the above objects, the electric wire with terminal according to the present invention comprises a coated electric wire having a wire conductor portion and an insulating coating portion that coats the wire conductor portion, a conductor joint portion to which a conductor exposed portion, which is a terminal portion of the wire conductor portion exposed by removing the insulating coating portion, is joined, and a coating joint portion to which a coating tip portion including a portion where the insulating coating portion is removed is joined, and the coating tip portion is joined to the coating joint portion by a curable resin, and the value of the expansion rate of the curable resin is equal to or greater than the value of the molding shrinkage rate of the coating material that constitutes the insulating coating portion.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the coating material is made of a crystalline material.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the curable resin is applied over a width wider than the width of the coated electric wire.

The electric wire with terminal according to the present invention is characterized in that, in the above invention, the curable resin is applied from the end of the terminal on the coating joint side to at least the terminal area where the insulating coating is removed, from the joint surface of the coating joint to a position covering 50% or more of the outer circumferential surface of the tip of the coating.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the curable resin is applied over the terminal area from the joint surface of the coating joint portion to a position that covers the entire outer circumferential surface of the coating tip portion.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the curable resin covers the portion where the insulating coating is removed and the entire exposed conductor portion.

The terminal-equipped electric wire according to the present invention is characterized in that, in the above invention, the coated electric wire is a flat electric wire in which the cross section of the electric wire conductor portion is flat.

The electric wire with terminal according to the present invention is characterized in that, in the above invention, the electric wire conductor portion is made of multiple strands arranged in parallel.

The electric wire with terminal according to the present invention is characterized in that, in the above invention, the exposed conductor portion of the coated electric wire is joined to the conductor joint portion of the terminal by welding.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the curable resin is a thermosetting resin, a room temperature curable resin, a photocurable resin, an anaerobic curable resin, or a moisture curable resin.

The terminal-attached electric wire according to the present invention is characterized in that, in the above invention, the curable resin is a resin that undergoes at least two of the following curing reactions: thermosetting, room temperature curing, photocuring, anaerobic curing, and moisture curing.

The electric wire with terminal according to the present invention is characterized in that, in the above invention, the covering material is made of a crystalline resin having a molding shrinkage rate of 1% or more, and the curable resin is a curable resin having an expansion and contraction rate of 4% or more in a temperature environment of -50°C or more and 150°C or less.

The terminal-equipped electric wire according to the present invention is also characterized in that, in the above invention, the length of the coating joint in the longitudinal direction of the coated electric wire is 10 mm or more and 20 mm or less.

In addition, in the electric wire with terminal according to the present invention, in the above invention, a cross-sectional area of the electric wire conductor portion is 10 mm ² or more and 100 mm ² or less.

The method for manufacturing an electric wire with a terminal according to the present invention includes a removing step of removing an end portion of an insulating coating of a coated electric wire having an electric wire conductor portion and an insulating coating portion that covers the electric wire conductor portion to expose the end portion of the electric wire conductor portion, and a joining step of joining a conductor exposure portion, which is the exposed end portion of the electric wire conductor portion, and a tip portion of the coating including the removed insulating coating portion, to a terminal, and is characterized in that the tip portion of the coating is joined to the terminal by a curable resin, and the value of the expansion and contraction rate of the curable resin is equal to or greater than the value of the molding shrinkage rate of the coating material that constitutes the insulating coating portion.

The present invention has the effect of realizing an electric wire with a terminal that can prevent the insulating coating from coming off the terminal and from being damaged.

FIG. 1 is a schematic diagram showing a configuration example of an electric wire with a terminal according to a first embodiment of the present invention. FIG. 2 is a top view of the electric wire with terminal shown in FIG. 1 . FIG. 3 is a cross-sectional view of the electric wire with terminal shown in FIG. 1 taken along line AA. FIG. 4 is a schematic diagram showing an example of a method for manufacturing an electric wire with a terminal according to the first embodiment of the present invention. FIG. 5 is a schematic diagram showing a configuration example of an electric wire with a terminal according to the second embodiment of the present invention. FIG. 6 is a top view of the electric wire with terminal shown in FIG. 5 . 7 is a cross-sectional view of the electric wire with terminal shown in FIG. 5 taken along line BB. FIG. 8 is a schematic diagram showing a configuration example of an electric wire with a terminal according to the third embodiment of the present invention. FIG. 9 is a top view of the electric wire with terminal shown in FIG. 8 . FIG. 10 is a cross-sectional view of the electric wire with terminal shown in FIG. 8 taken along line CC. FIG. 11 is a schematic diagram showing a configuration example of an electric wire with a terminal according to the fourth embodiment of the present invention. FIG. 12 is a top view of the electric wire with terminal shown in FIG. 11 .

Below, with reference to the drawings, a preferred embodiment of the electric wire with terminal and the manufacturing method of the electric wire with terminal according to the present invention will be described in detail. Note that the present invention is not limited to the embodiment described below. It should be noted that the drawings are schematic, and the dimensional relationships of each element, the ratios of each element, etc. may differ from the actual ones. There may be parts in which the dimensional relationships and ratios differ between the drawings. Also, the same reference numerals are used for the same or corresponding elements in each drawing.

(Embodiment 1)
First, the configuration of the electric wire with terminal according to the first embodiment of the present invention will be described. Fig. 1 is a schematic diagram showing one configuration example of the electric wire with terminal according to the first embodiment of the present invention. Fig. 1 shows an electric wire with terminal 1 according to the first embodiment as viewed from its width direction. Fig. 2 is a top view of the electric wire with terminal shown in Fig. 1 as viewed from above. Fig. 3 is a cross-sectional view of the electric wire with terminal shown in Fig. 1 taken along line A-A.

As shown in Figs. 1 to 3, the electric wire with terminal 1 according to the first embodiment includes a coated electric wire 10 and a terminal 20. The electric wire with terminal 1 also includes a cured product of a curable resin 30 that joins the tip of the insulating coating portion 15 of the coated electric wire 10 to the terminal 20. For ease of explanation, the electric wire with terminal 1 has a longitudinal direction X, a width direction Y, and a height direction Z as shown in Figs. 1 to 3. The longitudinal direction X, width direction Y, and height direction Z do not limit the electric wire with terminal 1.

As shown in Figs. 1 to 3, the coated electric wire 10 has a wire conductor portion 11 and an insulating coating portion 15 that coats the wire conductor portion 11. The wire conductor portion 11 is, for example, composed of a plurality of element wires 14 extending in the longitudinal direction X, and constitutes a conductor portion of a thick electric wire, which is an example of the coated electric wire 10. The wire conductor portion 11 may be a bundle of a plurality of element wires 14, or may be a strand of a plurality of element wires 14 (stranded wire). Examples of the material of the wire conductor portion 11 (i.e., the material of the element wires 14) include high-purity aluminum (Al) and aluminum alloys (Al alloys). In the present embodiment 1, the area of the cross section (cross-sectional area) of the wire conductor portion 11 shown in Fig. 3 corresponds to the sum of the cross-sectional areas of the plurality of element wires 14. For example, the cross-sectional area of the wire conductor portion 11 is 10 mm ² (10 sq) to 100 mm ² (100 sq).

The insulating coating portion 15 is made of a coating material that is an insulating resin, and is formed on the outer periphery of the wire conductor portion 11 as shown in Figs. 1 to 3. In this embodiment 1, the insulating coating portion 15 covers the entire area in the longitudinal direction X, excluding the terminal portion of the wire conductor portion 11. In detail, the terminal portion of the insulating coating portion 15 in the longitudinal direction X is removed in order to expose the terminal portion of the wire conductor portion 11 (the exposed conductor portion 12 shown in Figs. 1 and 2) from the insulating coating portion 15.

The terminal 20 is a terminal fitting to which the coated electric wire 10 is joined. In detail, the terminal 20 is made of a metal material such as copper or a copper alloy, and has a conductor joint 21 and a coating joint 22 to which the end portion of the coated electric wire 10 is joined, as shown in Figs. 1 and 2. The terminal 20 also has a terminal tip 23 on the front side of the conductor joint 21 in the longitudinal direction X. The terminal tip 23 is a terminal portion for connecting the terminal-attached electric wire 1 according to the first embodiment to another terminal-attached electric wire or a terminal of a power source, etc. This terminal tip 23 is provided with a structure for connecting to another terminal (for example, a circular through hole as shown in Fig. 2).

The conductor joint 21 is a portion of the terminal 20 to which the conductor exposed portion 12 of the coated electric wire 10 is joined. In this embodiment 1, the conductor exposed portion 12 is a terminal portion of the wire conductor portion 11 of the coated electric wire 10 that is exposed by removing the insulating coating portion 15. As shown in Figs. 1 and 2, the conductor joint 21 of the terminal 20 is joined to an intermediate portion (joining target portion) between the base end portion 13a on the rear side in the longitudinal direction X and the tip end portion 13b on the front side in the longitudinal direction X of the conductor exposed portion 12. In addition, as shown in Figs. 1 and 2, the conductor joint 21 is provided with a pair of side walls 21a and 21b for containing the joining target portion of the conductor exposed portion 12. The pair of side walls 21a and 21b are erected at both ends of the conductor joint 21 in the width direction Y so as to face each other in the width direction Y of the terminal 20. The dimensions of each of these side walls 21a, 21b are set according to the dimensions of the exposed conductor portion 12 of the coated wire 10 that is joined to the conductor joint portion 21.

The coating joint 22 is a portion of the terminal 20 to which the coating tip 16 of the coated electric wire 10 is joined. In this embodiment 1, the coating tip 16 is a portion including the removal edge 17 of the insulating coating 15 (specifically, the terminal portion of the insulating coating 15) of the insulating coating 15 of the coated electric wire 10 that is removed to expose the conductor exposed portion 12. As shown in Figs. 1 and 2, at least the coating tip 16 of the coated electric wire 10 is joined to the coating joint 22 of the terminal 20. For example, in this embodiment 1, the coating tip 16 and the base end 13a of the conductor exposed portion 12 (specifically, the portion extending from the removal edge 17 of the insulating coating 15) are joined to the coating joint 22.

In the first embodiment, the tip end 16 of the insulated electric wire 10 is joined to the insulated joint 22 of the terminal 20 by a curable resin 30. In detail, as shown in Figs. 1 to 3, the curable resin 30 is applied to the joint surface of the insulated joint 22 in a width wider than the width W1 of the insulated electric wire 10. As shown in Fig. 3, the width W1 of the insulated electric wire 10 is the maximum length of the insulated tip end 16 in the width direction Y that can be taken at each position in the height direction Z. For example, if the cross section of the insulated tip end 16 is circular, the width W1 corresponds to the outer diameter of the insulated tip end 16.

For example, as shown in Figs. 1 to 3, the curable resin 30 is applied over a terminal area from the end of the terminal 20 on the coating joint 22 side (i.e., the rear end 22a in the longitudinal direction X) to at least the removal edge 17 of the insulating coating 15, and is wider than the width W1 of the coated electric wire 10. At this time, the curable resin 30 is applied over the terminal area from the joint surface of the coating joint 22 (i.e., position P0 in the height direction Z shown in Fig. 3) to position P1 covering 50% or more of the outer circumferential surface of the coating tip 16. In this embodiment 1, for example, as shown in Figs. 1 and 2, the curable resin 30 is applied over the terminal area from the rear end 22a of the terminal 20 through the removal edge 17 of the insulating coating 15 to the base end 13a of the exposed conductor portion 12.

When the position P1 in the height direction Z of the curable resin 30 is a position in the height direction Z where the coated tip portion 16 can have the width W1, the curable resin 30 covers 50% of the outer peripheral surface of the coated tip portion 16.

As described above, the curable resin 30 applied to the joint surface of the coating joint 22 of the terminal 20 becomes a hardened product and bonds the coating tip 16 of the coated electric wire 10 and the coating joint 22 of the terminal 20. From the viewpoint that the hardened curable resin 30 follows the shrinkage deformation of the insulating coating part 15 of the coated electric wire 10 to maintain the joint state between the coating tip 16 and the coating joint 22, the value of the expansion rate of the curable resin 30 is equal to or greater than the molding shrinkage rate of the coating material constituting the insulating coating part 15 of the coated electric wire 10. In the present invention, the expansion rate (%) of the curable resin is a value that represents the expansion property of the curable resin itself. The molding shrinkage rate (%) of the coating material is the shrinkage rate of the coating material molded into the insulating coating part of the coated electric wire by extrusion molding in a contracted state after extrusion molding relative to the reference state at the time of extrusion molding.

From the viewpoint of increasing the heat resistance and chemical resistance of the insulating coating portion 15, the above-mentioned coating material is preferably made of a crystalline material, and particularly preferably made of a crystalline material with a molding shrinkage rate of 1% or more. Examples of such crystalline materials include crystalline resins such as polyethylene or polypropylene, whose molding shrinkage rate is 1% or more and 4% or less.

On the other hand, when the coating material of the insulating coating portion 15 is made of a crystalline material with a molding shrinkage rate of 1% or more, the curable resin 30 is preferably a curable resin with an expansion rate of 4% or more in a temperature environment of -50°C to 150°C. Examples of such curable resin 30 include urethane-based curable resins (UV-curable urethane resins, etc.) and acrylate-based curable resins. In addition, the curable resin 30 may be a thermosetting resin, a room temperature curable resin, a photocurable resin, an anaerobic curable resin, or a moisture curable resin, or may be a resin that undergoes at least two of the following curing reactions: thermosetting, room temperature curable, photocurable, anaerobic curable, and moisture curable.

In addition, when the insulating coating portion 15 is made of a crystalline resin having a molding shrinkage rate of 1% to 4% as described above, for example, if the wire length (length in the longitudinal direction X) of the coated electric wire 10 is 1 m to 5 m, the insulating coating portion 15 may shrink by 10 mm or more in the longitudinal direction X after extrusion molding of the crystalline resin. For this reason, from the viewpoint of reliably positioning the coating tip portion 16 of the insulating coating portion 15 on the joint surface of the coating joint portion 22, it is preferable that the lower limit of the length of the coating joint portion 22 in the longitudinal direction X of the coated electric wire 10 is 10 mm or more.

On the other hand, if the length of the coating joint 22 in the longitudinal direction X is excessively long, the weight of the terminal 20 and the weight of the cured product of the curable resin 30 that joins the coating joint 22 and the coating tip 16 will increase excessively. Furthermore, the cost of applying the curable resin 30 to the joint surface of the coating joint 22 will increase excessively. For this reason, from the viewpoint of avoiding an increase in the weight of the terminal 20 and the curable resin 30 and an increase in the cost of applying the curable resin 30, it is preferable that the upper limit of the length of the coating joint 22 in the longitudinal direction X of the coated electric wire 10 is 20 mm or less.

In view of the above, it is preferable that the length of the coating joint 22 in the longitudinal direction X of the coated electric wire 10 is 10 mm or more and 20 mm or less. In particular, it is preferable that the length of the coating joint 22 in the longitudinal direction X of the terminal region from the rear end 22a of the terminal 20 to the removal point 17 of the insulating coating portion 15 is 10 mm or more and 20 mm or less.

Next, a method for manufacturing the electric wire with terminal 1 according to the first embodiment of the present invention will be described. FIG. 4 is a schematic diagram showing an example of a method for manufacturing the electric wire with terminal according to the first embodiment of the present invention. The method for manufacturing the electric wire with terminal 1 (see FIGS. 1 to 3) includes a removal process for exposing the end portion of the wire conductor portion 11 of the coated electric wire 10 from the insulating coating portion 15, and a joining process for joining the exposed conductor portion 12 and the coating tip portion 16 of the coated electric wire 10 to the terminal 20.

In detail, as shown in FIG. 4, the manufacturing method of the electric wire with terminal 1 includes the above-mentioned removal step. In this removal step, of the coated electric wire 10 having the electric wire conductor portion 11 and the insulating coating portion 15 that covers the electric wire conductor portion 11, the terminal portion 18 of the insulating coating portion 15 is removed by stripping or the like. As a result, the conductor exposed portion 12, which is the terminal portion of the electric wire conductor portion 11, is exposed from the insulating coating portion 15 (state S1).

After the removal step is performed, the manufacturing method of the electric wire with terminal 1 includes the joining step as shown in FIG. 4. In this joining step, the conductor exposed portion 12, which is the exposed end portion of the electric wire conductor portion 11 of the coated electric wire 10, and the coating tip portion 16 including the stripped edge of the insulating coating portion 15 (removal edge 17 shown in FIGS. 1 and 2) are joined to the terminal 20 (state S2).

In detail, as shown in FIG. 4, the conductor exposed portion 12 is joined to the conductor joint portion 21 of the terminal 20. At this time, the joint target portion of the conductor exposed portion 12 is disposed between the side wall portions 21a, 21b of the conductor joint portion 21. The joint target portion of the conductor exposed portion 12 is the intermediate portion between the base end portion 13a and the tip end portion 13b of the conductor exposed portion 12 shown in FIG. 2. The joint target portion of the conductor exposed portion 12 is joined to the conductor joint portion 21 of the terminal 20 by, for example, welding (state S3). Examples of the welding method include ultrasonic welding.

4, the coating tip 16 is joined to the coating joint 22 of the terminal 20 by the hardening resin 30. In detail, the coating tip 16 is placed on the joint surface of the coating joint 22 of the terminal 20. Then, the hardening resin 30 is applied to the joint surface of the coating joint 22. As the hardening resin 30, a hardening resin having a value of an expansion and contraction rate equal to or greater than the molding shrinkage rate of the coating material constituting the insulating coating portion 15 is used. For example, the hardening resin 30 is applied from the end of the coating joint 22 side of the terminal 20 (i.e., the rear end 22a in the longitudinal direction X shown in Figs. 1 and 2) to at least the terminal region leading to the removal point 17 of the insulating coating portion 15, and is wider than the width W1 (see Fig. 3) of the coated electric wire 10. In this embodiment 1, the hardening resin 30 is applied from the joint surface of the coating joint 22 to a position P1 (see Fig. 3) covering 50% or more of the outer circumferential surface of the coating tip 16 over the above-mentioned terminal region. The hardening resin 30 thus applied is hardened by at least one of the following hardening reactions: heat hardening, room temperature hardening, light hardening, anaerobic hardening, and moisture hardening. The hardened hardening resin 30 bonds the coating tip 16 to the coating joint 22 of the terminal 20 (state S3).

In addition, in the above-mentioned process of joining the coated electric wire 10 and the terminal 20, the joining of the conductor exposed portion 12 and the conductor joint portion 21 of the terminal 20 may be performed before or after the joining of the coating tip portion 16 and the coating joint portion 22 of the terminal 20 with the curable resin 30, or may be performed in parallel.

As described above, in the first embodiment of the present invention, in the coated electric wire 10 having the electric wire conductor portion 11 and the insulating coating portion 15 that coats the electric wire conductor portion 11, the conductor exposed portion 12, which is the terminal portion of the electric wire conductor portion 11 and is exposed by removing the insulating coating portion 15, is joined to the conductor joint portion 21 of the terminal 20, and the coating tip portion 16, which includes the removed portion 17 of the insulating coating portion 15, is joined to the coating joint portion 22 of the terminal 20 by the curable resin 30, and the value of the expansion rate of this curable resin 30 is equal to or greater than the value of the molding shrinkage rate of the coating material that constitutes the insulating coating portion 15.

Therefore, unlike conventional electric wires with terminals in which the tip of the insulated electric wire is restrained by an insulation barrel and crimped to the insulated joint of the terminal, the cured product of the curable resin 30 that joins the tip of the insulated electric wire 10 to the insulated joint 22 of the terminal 20 can expand in accordance with the shrinkage of the tip of the insulated electric wire 16 after molding. Therefore, even if the tip of the insulated electric wire 16 shrinks after molding, the bond between the tip of the insulated electric wire 10 and the insulated joint 22 of the terminal 20 by the curable resin 30 can be maintained, and stress concentration between the tip of the insulated electric wire 16 and the cured product of the curable resin 30 can be alleviated. As a result, it is possible to prevent the insulating part 15 of the insulated electric wire 10 from coming off from the terminal 20 of the electric wire with terminal 1 and the insulating part 15 from being damaged.

(Embodiment 2)
Next, the configuration of an electric wire with terminal according to a second embodiment of the present invention will be described. Fig. 5 is a schematic diagram showing one configuration example of an electric wire with terminal according to a second embodiment of the present invention. Fig. 5 shows an electric wire with terminal 1A according to the second embodiment as viewed from its width direction. Fig. 6 is a top view of the electric wire with terminal shown in Fig. 5 as viewed from above. Fig. 7 is a cross-sectional view of the electric wire with terminal shown in Fig. 5 taken along line B-B.

As shown in Figures 5 to 7, the electric wire with terminal 1A according to the second embodiment includes a cured product of curable resin 30A instead of the cured product of curable resin 30 of the electric wire with terminal 1 according to the first embodiment described above. That is, in the electric wire with terminal 1A according to the second embodiment, the coating tip portion 16 of the coated electric wire 10 is joined to the coating joint portion 22 of the terminal 20 by the curable resin 30A. The other configurations are the same as those of the first embodiment, and the same components are denoted by the same reference numerals.

As shown in Figs. 5 to 7, the curable resin 30A is applied on the joint surface of the coating joint 22 to cover the entire removal edge 17 of the insulating coating 15 in the coated electric wire 10 and to a width wider than the width W1 of the coated electric wire 10. In detail, the curable resin 30A is applied from the joint surface of the coating joint 22 (i.e., position P0 in the height direction Z shown in Fig. 7) to position P2 covering the entire outer circumferential surface of the coating tip 16 over the terminal area from the rear end 22a of the terminal 20 to at least the removal edge 17 of the insulating coating 15. In this embodiment 2, for example, as shown in Figs. 5 and 6, the curable resin 30A is applied over the terminal area from the rear end 22a of the terminal 20 through the removal edge 17 of the insulating coating 15 to the base end 13a of the conductor exposed portion 12. The curable resin 30A applied in this manner covers the entire area including the outer circumferential surface of the coating tip 16 and the open end of the removal edge 17.

As described above, the curable resin 30A applied to the joint surface of the coating joint 22 of the terminal 20 hardens to join the coating tip 16 of the coated wire 10 and the coating joint 22 of the terminal 20, and also covers the entire removed edge 17 of the insulating coating 15 and the entire end of the base end 13a of the exposed conductor portion 12 extending from the coating tip 16. The value of the expansion rate and the constituent resin of the curable resin 30A are the same as those of the curable resin 30 in the above-mentioned embodiment 1.

The manufacturing method of the terminal-attached electric wire 1A according to the second embodiment of the present invention is the same as that of the first embodiment described above, except for the application of the curable resin 30A in the joining process for joining the conductor exposed portion 12 and the coating tip portion 16 of the coated electric wire 10 to the terminal 20.

In detail, as shown in Figures 5 to 7, in the joining process in this embodiment 2, the curable resin 30A is applied over the terminal area from the rear end 22a of the terminal 20 to at least the removal point 17 of the insulating coating portion 15, and from the joining surface of the coating joining portion 22 to position P2 (see Figure 3) covering the entire outer circumferential surface of the coating tip portion 16.

As described above, in the second embodiment of the present invention, the tip end 16 of the insulating coating 15 of the coated electric wire 10 is joined to the coating joint 22 of the terminal 20 by the curable resin 30A, and the curable resin 30A covers the entire tip end 16, and the rest is configured in the same manner as in the first embodiment. Therefore, the same effects as in the first embodiment can be obtained, and the bonding strength between the tip end 16 of the coated electric wire 10 and the coating joint 22 of the terminal 20 by the curable resin 30A can be further increased. Furthermore, the opening end 17 at the time of removing the tip end 16 of the coating can be blocked by the curable resin 30A, which prevents liquid from entering the insulating coating 15, and as a result, corrosion of the wire conductor 11 in the insulating coating 15 can be prevented.

(Embodiment 3)
Next, the configuration of an electric wire with terminal according to a third embodiment of the present invention will be described. Fig. 8 is a schematic diagram showing one configuration example of an electric wire with terminal according to the third embodiment of the present invention. Fig. 8 shows an electric wire with terminal 1B according to the third embodiment as viewed from its width direction. Fig. 9 is a top view of the electric wire with terminal shown in Fig. 8 as viewed from above. Fig. 10 is a cross-sectional view of the electric wire with terminal shown in Fig. 8 taken along line CC.

As shown in Figures 8 to 10, the electric wire with terminal 1B according to the third embodiment includes a flat insulated electric wire 10A instead of the insulated electric wire 10 of the electric wire with terminal 1A according to the second embodiment described above, and includes a cured product of curable resin 30B instead of the cured product of curable resin 30A. That is, in the electric wire with terminal 1B according to the third embodiment, the insulated tip portion 16A of the insulated electric wire 10A is joined to the insulated joint portion 22 of the terminal 20 by the curable resin 30B. The other configurations are the same as those of the second embodiment, and the same components are denoted by the same reference numerals.

As shown in Figs. 8 to 10, the coated electric wire 10A has a wire conductor portion 11A and an insulating coating portion 15A that coats the wire conductor portion 11A. The wire conductor portion 11A is a flat conductor portion that is long in the width direction Y. That is, the coated electric wire 10A is a flat electric wire in which the cross section of the wire conductor portion 11A is flat. For example, as shown in Fig. 10, the wire conductor portion 11A is composed of a plurality of strands 14 arranged in parallel. In an example of the wire conductor portion 11A shown in Fig. 10, seven strands 14 extending in the longitudinal direction X are arranged in parallel to form a long row in the width direction Y. The number of strands 14 that constitute the wire conductor portion 11A is not limited to seven as shown in Fig. 10, and may be two or more. The number of rows formed by these multiple strands 14 is not limited to one row as shown in Fig. 10, and may be multiple rows. The electric wire conductor portion 11A may be a flat bundle of multiple wires 14, or a flat strand of multiple wires 14. The material and cross-sectional area of such an electric wire conductor portion 11A are the same as those of the first and second embodiments described above.

The insulating coating portion 15A is made of a coating material that is an insulating resin, and is formed in a flat shape along the outer periphery of the electric wire conductor portion 11A, as shown in Figs. 8 to 10. In this embodiment 3, the insulating coating portion 15A covers the entire area in the longitudinal direction X, excluding the terminal portion of the electric wire conductor portion 11A. In detail, the terminal portion in the longitudinal direction X of the insulating coating portion 15A is removed in order to expose the terminal portion of the electric wire conductor portion 11A (the exposed conductor portion 12A shown in Figs. 8 and 9) from the insulating coating portion 15A. The coating material constituting the insulating coating portion 15A is the same as that of the insulating coating portion 15 in the above-mentioned embodiments 1 and 2.

In the third embodiment, the conductor exposed portion 12A of the coated electric wire 10A is joined to the conductor joint portion 21 of the terminal 20. The conductor exposed portion 12A is a terminal portion of the wire conductor portion 11A of the coated electric wire 10A that is exposed by removing the insulating coating portion 15A. For example, as shown in Figures 8 and 9, an intermediate portion (part to be joined) between the base end portion 13c on the rear side in the longitudinal direction X and the tip end portion 13d on the front side in the longitudinal direction X of the conductor exposed portion 12A is joined to the conductor joint portion 21 of the terminal 20.

In the third embodiment, at least the tip end 16A of the insulated wire 10A is joined to the insulated joint 22 of the terminal 20 by the curable resin 30B. The tip end 16A is a portion of the insulated wire 10A that includes the removed portion 17A of the insulated wire 15A (specifically, the terminal portion of the insulated wire 15A) that was removed to expose the exposed conductor portion 12A. For example, as shown in Figs. 8 and 9, the tip end 16A and the base end 13a of the exposed conductor portion 12A (specifically, the portion extending from the removed portion 17A of the insulated wire 15A) are joined to the insulated joint 22 by the curable resin 30B.

As shown in Figures 8 to 10, the curable resin 30B is applied to the joint surface of the coating joint 22 in a width wider than the width W2 of the coated electric wire 10A. As shown in Figure 10, the width W2 of the coated electric wire 10A is the maximum length in the width direction Y of the coating tip 16A that can be taken at each position in the height direction Z. For example, if the cross section of the coating tip 16A has a flat shape that is long in the width direction Y, the width W2 corresponds to the length between both ends of the coating tip 16A in the width direction Y.

For example, as shown in Figures 8 to 10, the curable resin 30B is applied over the terminal area from the rear end 22a of the terminal 20 to at least the removal edge 17A of the insulating coating 15A, and is wider than the width W2 of the coated electric wire 10A. In this embodiment 3, the curable resin 30B is applied over the terminal area from the joint surface of the coating joint 22 (i.e., position P0 in the height direction Z shown in Figure 10) to position P3 covering the entire outer circumferential surface of the coating tip 16A. For example, as shown in Figures 8 and 9, the curable resin 30B is applied over the terminal area from the rear end 22a of the terminal 20 through the removal edge 17A of the insulating coating 15A to the base end 13c of the exposed conductor portion 12A.

As described above, the curable resin 30B applied to the joint surface of the coating joint 22 of the terminal 20 becomes a cured product and joins the coating tip 16A of the coated electric wire 10A to the coating joint 22 of the terminal 20, and also covers the entire removed portion 17A of the insulating coating 15A and the entire end portion of the base end 13c of the exposed conductor portion 12A extending from the coating tip 16A. The value of the expansion rate and the constituent resin of the curable resin 30B are the same as those of the curable resins 30 and 30A in the above-mentioned embodiments 1 and 2.

The manufacturing method of the electric wire with terminal 1B according to the third embodiment of the present invention is the same as that of the second embodiment, except that the coated electric wire 10A to be joined to the terminal 20 is a flat electric wire. That is, in the manufacturing method of the electric wire with terminal 1B, the removal step is the same as the step in which the coated electric wire 10 (thick electric wire) shown in FIG. 4 is replaced with the coated electric wire 10A (flat electric wire). The joining step is the same as the step in which the coated electric wire 10 in the second embodiment is replaced with the coated electric wire 10A and the curable resin 30A is replaced with the curable resin 30B. That is, in this joining step, the curable resin 30B is applied from the rear end 22a of the terminal 20 to the terminal region at least up to the removal edge 17A of the insulating coating portion 15A, from the joint surface of the coating joint portion 22 to a position P3 (see FIG. 10) covering the entire outer circumferential surface of the coating tip portion 16A, and then cured.

As described above, in the third embodiment of the present invention, the coated electric wire 10A joined to the terminal 20 is a flat electric wire, and the coated tip portion 16A of the insulating coating portion 15A of this coated electric wire 10A is joined to the coating joint portion 22 of the terminal 20 by the curable resin 30B, and the rest is configured in the same manner as in the second embodiment. Therefore, even when a flat electric wire (coated electric wire 10A) is joined to the terminal 20, the same effects as those of the second embodiment described above can be obtained.

(Embodiment 4)
Next, the configuration of an electric wire with terminal according to a fourth embodiment of the present invention will be described. Fig. 11 is a schematic diagram showing one configuration example of an electric wire with terminal according to the fourth embodiment of the present invention. Fig. 11 shows an electric wire with terminal 1C according to the fourth embodiment as viewed from its width direction. Fig. 12 is a top view of the electric wire with terminal shown in Fig. 11 as viewed from above.

As shown in Figures 11 and 12, the terminal-attached electric wire 1C according to the fourth embodiment includes a cured product of curable resin 30C instead of the cured product of curable resin 30B of the terminal-attached electric wire 1B according to the third embodiment. That is, in the terminal-attached electric wire 1C according to the fourth embodiment, the coating tip portion 16A of the coated electric wire 10A is joined to the coating joint portion 22 of the terminal 20 by the curable resin 30C. The other configurations are the same as those of the third embodiment, and the same components are denoted by the same reference numerals.

As shown in Figs. 11 and 12, the hardening resin 30C is applied to the joint side surface of the terminal 20 so as to cover the entire terminal portion of the coated electric wire 10A. In detail, the hardening resin 30C is applied over the terminal area from the rear end 22a of the terminal 20 through the removal portion 17A of the insulating coating portion 15A to the entire tip portion 13d of the conductor exposed portion 12A, from the joint side surface of the terminal 20 to a height position (for example, position P3 in the height direction Z shown in Fig. 10) that covers the entire outer peripheral surface of the conductor exposed portion 12A and the coating tip portion 16A. The joint side surface of the terminal 20 is the surface that includes the respective joint surfaces of the conductor joint portion 21 and the coating joint portion 22 among both sides of the terminal 20 in the height direction Z (thickness direction).

As shown in Figures 11 and 12, the curable resin 30C applied as described above hardens to join the tip 16A of the insulated wire 10A to the joint 22 of the terminal 20, and also covers the entire exposed conductor portion 12A and the removed portion 17A of the insulating coating portion 15A. The value of the expansion/contraction rate and the constituent resins of the curable resin 30C are the same as those of the curable resins 30, 30A, and 30B in the above-mentioned embodiments 1 to 3.

The manufacturing method of the terminal-attached electric wire 1C according to the fourth embodiment of the present invention is the same as that of the third embodiment described above, except for the application of the curable resin 30C in the joining process for joining the conductor exposed portion 12A and the coating tip portion 16A of the coated electric wire 10A to the terminal 20.

In detail, as shown in Figures 11 and 12, in the joining process in this embodiment 4, the curable resin 30C is applied over the terminal area from the rear end 22a of the terminal 20, through the removal edge 17A of the insulating coating portion 15A, to the entire tip 13d of the conductor exposed portion 12A, up to a height position that covers the entire conductor exposed portion 12A and the coating tip portion 16A.

As described above, in the fourth embodiment of the present invention, the tip end 16A of the insulating coating 15A of the coated electric wire 10A is joined to the coating joint 22 of the terminal 20 by the curable resin 30C, and the curable resin 30C covers the entire exposed conductor portion 12A and the tip end 16A of the coated electric wire 10A, and the rest of the configuration is the same as in the third embodiment. Therefore, the same effects as those of the third embodiment described above can be obtained, and the bonding strength between the tip end 16A of the coated electric wire 10A and the coating joint 22 of the terminal 20 by the curable resin 30C can be further increased. Furthermore, the entire area 17A where the insulating coating 15A is removed and the exposed conductor portion 12A extending (exposed) from the removed area 17A can be sealed with the curable resin 30C, which prevents liquid from adhering to the entire wire conductor portion 11A, including the exposed conductor portion 12A. As a result, not only can corrosion of the wire conductor portion 11A within the insulating coating 15A occur, but also corrosion of the exposed conductor portion 12A exposed from the insulating coating 15A can be prevented.

In the above-mentioned first to fourth embodiments, the conductor exposed portion of the insulated electric wire is joined to the conductor joint portion of the terminal by welding, but the present invention is not limited to this. For example, a wire barrel may be provided in the terminal, and the conductor exposed portion of the insulated electric wire may be restrained (crimped) by the wire barrel, thereby crimping the conductor exposed portion to the conductor joint portion of the terminal. Alternatively, the joining method between the conductor exposed portion of the insulated electric wire and the conductor joint portion of the terminal may be a method other than welding such as ultrasonic joining or crimping with a wire barrel.

In addition, in the above-mentioned first to fourth embodiments, a terminal having a pair of side walls at both widthwise ends of the conductor joint is exemplified, but the present invention is not limited to this. For example, a pair of side walls facing each other in the widthwise direction may be provided at both widthwise ends of the coating joint of the terminal, and the coating tip of the coated electric wire may be bonded between the pair of side walls with a curable resin. In this case, the pair of side walls of the coating joint may be an extension of the pair of side walls of the conductor joint toward the coating joint, or may be independent of the pair of side walls of the conductor joint.

In addition, in the above-mentioned embodiments 1 to 4, a crystalline material is used as the insulating material constituting the insulating coating of the coated electric wire, but the present invention is not limited to this. For example, the insulating material may be a non-crystalline material.

In addition, in the above-mentioned embodiments 1 to 4, the wire conductor portion of the covered electric wire is composed of multiple strands, but the present invention is not limited to this. For example, the wire conductor portion of the covered electric wire may be composed of a single strand of thick wire having a circular cross section, or may be composed of a single strand of flat wire (rectangular strand) having a flat cross section. In addition, the covered electric wire may be the above-mentioned thick wire or flat wire, or may be a covered electric wire other than these (such as a thin covered electric wire).

In addition, in the above-mentioned first to fourth embodiments, the wire conductor portion is made of Al or an Al alloy, but the present invention is not limited to this. For example, the wire conductor portion of the insulated wire may be made of a metal material other than Al or an Al alloy, such as copper or a copper alloy. Furthermore, the terminal (terminal metal fitting) to which the end portion of the insulated wire is joined is not limited to being made of copper or a copper alloy, and may be made of a metal material other than these.

The present invention is not limited to the above-mentioned embodiments 1 to 4, and the present invention also includes configurations in which the above-mentioned components are appropriately combined. For example, the terminal-attached electric wire according to the present invention may be one in which the coated electric wire 10 (thick electric wire) of the terminal-attached electric wire 1 according to the above-mentioned embodiment 1 is replaced with the coated electric wire 10A (flat electric wire) of embodiment 3 (a combination of embodiments 1 and 3), or one in which the coated electric wire 10A (flat electric wire) of the terminal-attached electric wire 1C according to the above-mentioned embodiment 4 is replaced with the coated electric wire 10 (thick electric wire) of embodiment 1 (a combination of embodiments 1 and 4). In addition, all other embodiments, examples, operational techniques, etc. made by those skilled in the art based on the above-mentioned embodiments 1 to 4 are included in the scope of the present invention.

1, 1A, 1B, 1C Electric wire with terminal 10, 10A Insulated electric wire 11, 11A Electric wire conductor portion 12, 12A Conductor exposed portion 13a, 13c Base end portion 13b, 13d Tip portion 14 Wire 15, 15A Insulating coating portion 16, 16A Coating tip portion 17, 17A Removal point 18 End portion 20 Terminal 21 Conductor joint portion 21a, 21b Side wall portion 22 Coating joint portion 22a Rear end portion 23 Terminal tip portion 30, 30A, 30B, 30C Curable resin P0, P1, P2, P3 Position X Longitudinal direction Y Width direction Z Height direction

Claims (15)

A coated electric wire having an electric wire conductor portion and an insulating coating portion that coats the electric wire conductor portion;
a terminal having a conductor joint portion to which a conductor exposed portion, which is an end portion of the electric wire conductor portion exposed by removing the insulating coating, is joined, and a coating joint portion to which a coating tip portion including a portion where the insulating coating is removed is joined;
Equipped with
the coated tip portion is joined to the coated joint portion by a hardening resin;
The value of the expansion/contraction rate of the curable resin is equal to or greater than the value of the molding shrinkage rate of the coating material constituting the insulating coating portion.
A terminal-attached electric wire. The coating material is made of a crystalline material.
The electric wire with terminal according to claim 1 . The curable resin is applied over a width wider than the width of the coated electric wire.
3. The electric wire with terminal according to claim 1 or 2. The curable resin is applied from the end of the terminal on the coating joint side to at least a terminal region where the insulating coating is removed, from a joint surface of the coating joint to a position covering 50% or more of an outer peripheral surface of the coating tip.
4. The electric wire with terminal according to claim 1, The curable resin is applied over the terminal region from the joint surface of the coating joint portion to a position covering the entire outer peripheral surface of the coating tip portion.
The electric wire with terminal according to claim 4 . The curable resin covers the removed portion of the insulating coating portion and the entire exposed conductor portion.
6. The electric wire with terminal according to claim 1, The coated electric wire is a flat electric wire in which the cross section of the electric wire conductor portion is flat.
7. The electric wire with terminal according to claim 1, The electric wire conductor portion is composed of a plurality of wires arranged in parallel.
The electric wire with terminal according to claim 7 . The exposed conductor portion of the coated electric wire is joined to the conductor joint portion of the terminal by welding.
The electric wire with terminal according to any one of claims 1 to 8. The curable resin is a thermosetting resin, a room temperature curable resin, a photocurable resin, an anaerobic curable resin, or a moisture curable resin.
The electric wire with terminal according to any one of claims 1 to 9. The curable resin is a resin that undergoes at least two curing reactions among thermosetting, room temperature curing, photocuring, anaerobic curing, and moisture curing.
The electric wire with terminal according to any one of claims 1 to 9. The coating material is made of a crystalline resin having a molding shrinkage rate of 1% or more,
The curable resin is a curable resin having an expansion/contraction rate of 4% or more in a temperature environment of -50°C or more and 150°C or less.
The electric wire with terminal according to any one of claims 1 to 11. The length of the coating joint portion in the longitudinal direction of the coated electric wire is 10 mm or more and 20 mm or less.
The electric wire with terminal according to any one of claims 1 to 12. The cross-sectional area of the electric wire conductor portion is ¹⁰ mm2 or more and ¹⁰⁰ mm2 or less.
The electric wire with terminal according to any one of claims 1 to 13. a removing step of removing an end portion of the insulating coating of a coated electric wire having an electric conductor portion and an insulating coating portion covering the electric conductor portion to expose the end portion of the electric conductor portion;
a joining step of joining a conductor exposed portion, which is an exposed end portion of the electric wire conductor portion, and a coating tip portion including a portion where the insulating coating portion is removed, to a terminal;
Including,
the tip end of the coating is bonded to the terminal by a hardening resin;
The value of the expansion/contraction rate of the curable resin is equal to or greater than the value of the molding shrinkage rate of the coating material constituting the insulating coating portion.
The method for producing an electric wire with terminal is characterized in that

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