阅读说明：本技术 具有端子的电线及其制造方法 (Electric wire with terminal and method for manufacturing same ) 是由 佐藤知哉 伊藤直树 于 2019-07-11 设计创作，主要内容包括：提供了一种具有端子的电线及其制造方法。在具有端子的电线中,在芯线夹在保护构件和端子接头之间的状态下,保护构件、芯线和端子接头通过从超声波焊头经由保护构件施加的超声波振动彼此一体地连接。因此,超声波焊头不可能直接按压芯线,并且超声波焊头的按压部分的边缘(特别是后边缘)不可能与芯线直接接触。由此,在超声波接合的时候,可以缓和由于超声波焊头的按压部分的边缘(特别是后边缘)引起的相对于芯线的应力集中,并且可以抑制芯线的断开。(Provided are an electric wire with a terminal and a method of manufacturing the same. In the electric wire with the terminal, the sheathing member, the core wire, and the terminal fitting are integrally connected to each other by ultrasonic vibration applied from the ultrasonic horn via the sheathing member in a state where the core wire is sandwiched between the sheathing member and the terminal fitting. Therefore, the ultrasonic horn cannot directly press the core wire, and the edge (particularly, the rear edge) of the pressed portion of the ultrasonic horn cannot directly contact the core wire. Thereby, at the time of ultrasonic bonding, stress concentration with respect to the core wire due to the edge (particularly, the rear edge) of the pressed portion of the ultrasonic horn can be relaxed, and disconnection of the core wire can be suppressed.)

1. An electric wire with a terminal, wherein a core wire exposed from an end of the electric wire and the terminal are connected by ultrasonic bonding, the electric wire with a terminal comprising:

a protective member for protecting the core wire,

wherein the core wire is integrally connected to the sheathing member and the terminal by ultrasonic vibration applied in a pressurized state from an ultrasonic horn via the sheathing member in a state of being sandwiched between the sheathing member and the terminal.

2. The electric wire with terminal according to claim 1,

wherein the dimension of the sheathing member is set substantially the same as the dimension of the tip portion of the ultrasonic horn that is in contact with the sheathing member, in a direction orthogonal to the core wire and orthogonal to the pressing direction.

3. The electric wire with terminal according to claim 2,

wherein a dimension of the sheathing member, in a direction orthogonal to a core wire and orthogonal to the pressing direction, is equal to or larger than a dimension of the tip portion of the ultrasonic horn that is in contact with the sheathing member minus a diameter of a strand of the core wire, and is equal to or smaller than a dimension of the tip portion of the ultrasonic horn.

4. The electric wire with terminal according to claim 1,

wherein a dimension of the sheathing member is 2/3 or more of a dimension of a tip portion of the ultrasonic horn that is in contact with the sheathing member, and is smaller than the dimension of the tip portion of the ultrasonic horn, in a direction orthogonal to the core wire and orthogonal to a pressing direction.

5. The electric wire with terminal according to claim 4,

wherein the sheathing member has a chamfered portion at an edge of a side surface of the sheathing member facing the core wire.

6. The electric wire with terminal according to claim 1,

wherein a dimension of the sheathing member is set larger than a dimension of a tip portion of the ultrasonic horn, which is in contact with the sheathing member, in a direction orthogonal to the core wire and orthogonal to a pressing direction.

7. The electric wire with terminal according to any one of claims 1 to 6,

wherein a dimension of the sheathing member in a direction parallel to the core wire is set larger than a dimension of a tip portion of the ultrasonic horn that is in contact with the sheathing member.

8. The electric wire with terminal according to any one of claims 1 to 7,

wherein the size of the protective member is set to be equal to or larger than the diameter of the strands of the core wire in the pressing direction.

9. The electric wire with terminal according to any one of claims 1 to 8,

wherein the protective member is formed of the same material as the core wire.

10. A method of manufacturing an electric wire having a terminal, in which a core wire exposed from an end portion of the electric wire and the terminal are connected by ultrasonic bonding, the method comprising:

placing the terminal on an anvil, disposing the core wire on the terminal, and disposing a protective member on the core wire; and

in a state where the core wire is pressed against the terminal via the protective member, ultrasonic vibration is applied via the protective member by an ultrasonic horn disposed above the anvil, whereby the protective member, the core wire, and the terminal are integrally connected.

Technical Field

The present invention relates to an electric wire having a terminal formed by ultrasonically bonding the terminal to a core wire exposed to a terminal of the electric wire, and a method of manufacturing the electric wire.

Background

As an electric wire with a terminal in the related art, in which the terminal is connected to a core wire by ultrasonic bonding, an electric wire with a terminal described in the following patent documents is known.

In the electric wire with the terminal, as shown in fig. 12, the core wire 102 of the terminal-processed electric wire 101 is sandwiched between the plate-like terminal fitting 103 placed on the anvil 104 and the ultrasonic horn 105, and the core wire 102 and the terminal fitting 103 are connected by applying ultrasonic vibration in a pressurized state.

Disclosure of Invention

However, in the case of a conventional electric wire having a terminal, the edge 105a of the ultrasonic horn 105 is in direct contact with the core wire 102. Therefore, at the time of pressurization accompanying ultrasonic bonding, stress concentration due to the edge 105a of the ultrasonic horn 105 may occur in the shearing direction of the core wire 102, and a part (strand) 102a of the core wire 102 may be broken (see a partially enlarged view in fig. 12).

The present invention has been made in view of these problems, and an object of the present invention is to provide an electric wire with a terminal capable of suppressing disconnection of a core wire at the time of ultrasonic bonding, and a method for manufacturing the same.

The present invention is an electric wire having a terminal to which a core wire exposed from an end of the electric wire is connected by ultrasonic bonding. In one aspect, the core wire is integrally connected to the sheathing member and the terminal by ultrasonic vibration applied in a pressurized state from an ultrasonic horn via the sheathing member in a state of being sandwiched between the sheathing member and the terminal.

In another aspect of the electric wire with terminal, it is desirable that the size of the sheathing member is set substantially the same as the size of the tip portion of the ultrasonic horn which is in contact with the sheathing member, in a direction orthogonal to the core wire and orthogonal to the pressing direction.

In this way, since the width dimension of the sheathing member is set substantially the same as the width dimension of the tip portion of the ultrasonic horn, the core wire can be protected in the width direction of the sheathing member without excess or deficiency.

In still another aspect of the electric wire with terminal, it is desirable that the size of the sheathing member, in a direction orthogonal to the core wire and orthogonal to the pressing direction, is preferably equal to or larger than a size of a tip portion of the ultrasonic horn which is in contact with the sheathing member minus a diameter of a strand of the core wire, and equal to or smaller than a size of the tip portion of the ultrasonic horn.

In this way, since the lower limit of the width dimension of the sheathing member is obtained by subtracting the diameter of the core wire from the width dimension of the tip portion of the ultrasonic horn, the wires (all strands) constituting the core wire overlap with the sheathing member in the width direction of the sheathing member, and the strands of the core wire do not protrude from the sheathing member. As a result, the disconnection of the core wire can be effectively suppressed.

Further, since the upper limit of the width dimension of the protective member is set to the width dimension of the tip portion of the ultrasonic horn, the unnecessary portion of the protective member is reduced, and the yield of the material of the protective member can be improved. As a result, the manufacturing cost of the electric wire with the terminal can be reduced.

In still another aspect of the electric wire with terminal, the dimension of the protective member is preferably 2/3 or more of the dimension of the tip portion of the ultrasonic horn which is in contact with the protective member, and smaller than the dimension of the tip portion of the ultrasonic horn, in a direction orthogonal to the core wire and orthogonal to the pressing direction.

When the core wire is pressurized by the ultrasonic horn, in particular, stress concentration may occur in the region 2/3 of the size of the tip portion of the ultrasonic horn having a large crushing margin. Therefore, since the lower limit of the width dimension of the protective member is set to 2/3 of the width dimension of the tip portion of the ultrasonic horn, it is possible to protect the region where stress concentration is likely to occur by the protective member while suppressing the material cost of the protective member. As a result, suppression of disconnection of the core wire and reduction in manufacturing cost (material cost of the protective member) can be achieved.

Further, since the width dimension of the sheathing member is set to be equal to or greater than 2/3 of the width dimension of the tip portion of the ultrasonic horn and smaller than the width dimension of the tip portion of the ultrasonic horn, the sheathing member can be shared with respect to the core wire within a predetermined range in which the width dimension after joining is relatively large with respect to the width dimension of the sheathing member. As a result, it is not necessary to prepare a protective member for each width dimension after joining the core wires, and the productivity of the electric wire with the terminal can be improved and the manufacturing cost can be reduced.

According to still another aspect of the electric wire with a terminal, it is desirable for the protective member to have a chamfered portion at an edge of a side surface facing the core wire.

In particular, when the width dimension of the sheathing member is smaller than the width dimension of the distal end portion of the ultrasonic horn, the core wire may be pressed by both side edges of the sheathing member in a direction parallel to the core wire. Therefore, by providing the chamfered portion on the side surface of the core wire facing the protective member, stress concentration due to the edges on both sides of the protective member can be suppressed, and damage to the core wire can be suppressed even in the direction parallel to the core wire.

In still another aspect of the electric wire with terminal, a dimension of the protective member is set larger than a dimension of a tip portion of the horn which is in contact with the protective member in a direction orthogonal to the core wire and orthogonal to the pressing direction.

In this way, since the width dimension of the sheathing member is set larger than the width dimension of the distal end portion of the ultrasonic horn, the sheathing member can be shared with respect to the core wire within a predetermined range in which the width dimension after joining is relatively small with respect to the width dimension of the sheathing member. As a result, it is not necessary to prepare a protective member for each width dimension after joining the core wires, and the productivity of the electric wire with the terminal can be improved and the manufacturing cost can be reduced.

In still another aspect of the electric wire with terminal, the size of the protective member is set larger than the size of the tip portion of the ultrasonic horn which is in contact with the protective member in the direction parallel to the core wire.

Since the depth dimension of the sheathing member is set larger than the depth dimension of the distal end portion of the ultrasonic horn, it is impossible for the distal end portion of the ultrasonic horn to directly press the core wire on the proximal end side of the core wire. As a result, the disconnection of the core wire can be effectively suppressed.

In still another aspect of the electric wire with a terminal, it is desirable that the size of the protective member in the pressing direction is set to be equal to or larger than the diameter of the strands of the core wire.

In this way, since the thickness dimension of the sheathing member is set to be at least equal to or greater than the diameter of the strands of the core, the sheathing member can withstand a shearing force that can be received by each strand of the core at least from the tip portion of the ultrasonic horn. In other words, the sheathing member may ensure rigidity capable of withstanding the shearing force that may be received by each strand of the core wire from the pressing portion of the ultrasonic horn. Therefore, the disconnection of the core wire can be effectively suppressed by the protective member.

In still another aspect of the electric wire with terminal, it is desirable that the protective member is formed of the same material as the core wire.

In this way, since the sheathing member is formed of the same material as the core wire, a good connection between the sheathing member and the core wire by ultrasonic bonding can be obtained, and the sheathing member and the core wire can be more firmly connected.

From another perspective, the present invention is a method of manufacturing an electric wire with a terminal, in which a core wire exposed from an end of the electric wire and a terminal fitting are connected by ultrasonic bonding. In one aspect thereof, the method includes the steps of placing the terminal fitting on an anvil, disposing a core wire on the terminal fitting, and disposing a protective member on the core wire, and in a state where the core wire is pressed against the terminal via the protective member, applying ultrasonic vibration via the protective member by an ultrasonic horn disposed above the anvil, thereby integrally connecting the protective member, the core wire, and the terminal fitting.

According to the present invention, since the core wire is ultrasonically bonded in a state of being sandwiched between the plate-like sheathing member and the terminal fitting, it is impossible for the tip portion of the ultrasonic horn to directly press the core wire at the time of ultrasonic bonding. That is, the edge of the distal end portion of the ultrasonic horn may not be in direct contact with the core wire. As a result, stress concentration with respect to the core wire due to the edge of the tip portion of the ultrasonic horn at the time of ultrasonic bonding is relaxed, and disconnection of the core wire can be suppressed.

Drawings

Fig. 1 is a perspective view of an electric wire with a terminal according to a first embodiment of the present invention;

fig. 2 is a perspective view showing a state before ultrasonic bonding of an electric wire having a terminal according to the first embodiment of the present invention;

FIG. 3 is an arrow view of FIG. 2 viewed from direction A;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 3;

fig. 5A is an arrow view corresponding to fig. 3 showing a state after ultrasonic bonding, and fig. 5B is a sectional view taken along the line C-C of fig. 5A;

fig. 6A is a perspective view of an electric wire with a terminal according to a modification of the first embodiment of the present invention, and fig. 6B is a sectional view taken along line D-D of fig. 6A;

fig. 7A is a perspective view of an electric wire with a terminal according to a second embodiment of the present invention, and fig. 7B is a sectional view taken along line E-E of fig. 7A;

fig. 8 is a front view showing a state before ultrasonic bonding of an electric wire with a terminal according to the second embodiment of the present invention;

fig. 9A is a perspective view of an electric wire with a terminal according to a modification of the second embodiment of the present invention, and fig. 9B is a sectional view taken along the line B-B of fig. 9A;

fig. 10 is a perspective view of an electric wire with a terminal according to a third embodiment of the present invention;

fig. 11 is a front view showing a state before ultrasonic bonding of an electric wire with a terminal according to a third embodiment of the present invention; and

fig. 12 is a sectional view showing a state in which an electric wire having a terminal is in ultrasonic bonding.

Detailed Description

Hereinafter, embodiments of an electric wire with a terminal and a method of manufacturing the same according to the present invention will be described with reference to the accompanying drawings.

(arrangement of electric wire with terminal)

A specific configuration of the electric wire with a terminal according to the present embodiment will be described in detail with reference to fig. 1 to 4.

As shown in fig. 1, in the electric wire with a terminal according to the present embodiment, ultrasonic bonding is performed in a state where the core wire 3 exposed by removing the insulating coating 2 at the terminal of the electric wire 1 is sandwiched between the sheathing member 5 and the terminal fitting 4. Thus, the sheathing member 5, the core wire 3, and the terminal fitting 4 are integrally connected (joined).

The electric wire 1 is an aluminum electric wire in which the core wire 3 is formed of, for example, an aluminum stranded wire. Then, the insulating coating 2 in a predetermined range of the terminal of the electric wire 1 is removed, and the distal end portion of the core wire 3 thus exposed is connected (joined) to the proximal end portion of the terminal fitting 4 by ultrasonic joining. Specifically, by pressing with ultrasonic bonding, the connection region (ultrasonic bonding region) having the terminal fitting 4 is crushed into a substantially rectangular plate shape along the terminal fitting 4. The electric wire 1 may be, in addition to an aluminum electric wire, an electric wire made of another conductive metal material, such as a copper electric wire, in which the core wire 3 is formed of copper, for example. In addition, the electric wire 1 may be formed of a copper alloy or an aluminum alloy. The electric wire 1 may be formed by plating a copper wire or an aluminum wire (e.g., Sn, Ni, etc.), or may be formed by adding carbon nanotubes to a conductive material such as copper or aluminum.

The terminal fitting 4 is formed of a conductive metal material (e.g., copper or aluminum) into a substantially flat plate shape. Although the terminal fitting 4 is formed in a simple plate shape by the illustration of fig. 1, the present invention is not limited thereto. In other words, in addition to the plate-shaped member, for example, the terminal fitting 4 may be a terminal fitting having a so-called round or Y-shaped terminal connection portion integrally formed with the tip end portion, and the terminal fitting 4 itself may be configured as a wire connection member.

The protective member 5 is formed of aluminum, which is the same material as the core wire 3 of the electric wire 1, and is formed in a substantially flat plate shape. More specifically, the protective member 5 is formed in a rectangular flat plate shape having a rectangular shape in both plan view and cross section. The protective member 5 need not be limited to the same material as the core wire 3 of the electric wire 1, and may be formed of a material different from that of the core wire 3 of the electric wire 1. Specifically, for example, the protective member 5 made of aluminum may be used for the copper wire.

The protective member 5 may be formed of another conductive metal such as copper in addition to aluminum. At this time, the material of the protective member 5 may be not only pure aluminum or pure copper but also an alloy thereof (aluminum alloy or copper alloy), and may be plated on the aluminum or copper (for example, Sn, Ni, or the like). In addition, the protective member 5 may be formed by adding carbon nanotubes to a conductive material such as aluminum or copper.

Further, the protective member 5 may be formed not only of a metal material but also of, for example, a resin material. That is, a resin material may be used as the material of the sheathing member 5, as long as the resin material can be attached to the core wire 3 without being welded by ultrasonic bonding to an ultrasonic horn 7 (see fig. 2) described later.

Further, as shown in fig. 3, a dimension (hereinafter simply referred to as "width dimension") X in a direction perpendicular to the core wire 3 of the sheathing member 5 is set substantially the same as a width dimension Wx of a pressing portion 72 of an ultrasonic horn 7 described later. More specifically, when the width dimension of the pressing portion 72 of the ultrasonic horn 7 is Wx and the diameter of the strand (one metal wire constituting the core wire 3) 3a of the core wire 3 is D, the width dimension X of the sheathing member 5 is set to satisfy "(Wx-D). ltoreq.X.ltoreq.Wx". That is, the width dimension X of the sheathing member 5 is equal to or greater than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7 minus the diameter D of the strands 3a of the core wire 3 and equal to or less than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7.

Further, when Wy denotes a depth dimension of the pressing portion 72 of the ultrasonic horn 7 described later, a dimension (hereinafter simply referred to as "depth dimension") Y in a direction parallel to the core wire 3 of the holding member 5 is set to satisfy "Wy ≦ Y". That is, the depth dimension Y of the sheathing member 5 is set to be equal to or greater than the depth dimension Wy of the pressing portion 72 of the ultrasonic horn 7.

In addition, when D denotes the diameter of the strands 3a of the core wire 3, a dimension (hereinafter, simply referred to as "thickness dimension") Z in a direction perpendicular to the core wire 3 of the sheathing member 5 and parallel to the direction in which the ultrasonic horn 7 moves up and down is set to satisfy "D ≦ Z". That is, the thickness dimension Z of the sheathing member 5 is set to be equal to or greater than the diameter D of the wire 3a of the core wire 3.

(method of manufacturing electric wire with terminal)

Before describing a method of manufacturing an electric wire with a terminal, an ultrasonic bonding device for ultrasonic bonding of the electric wire to the terminal will be described with reference to fig. 2 to 4.

As shown in fig. 2 to 4, the ultrasonic bonding apparatus includes: an anvil 6 serving as a base having a substantially smooth upper surface; an ultrasonic horn 7 provided to be movable up and down above the anvil 6; and a pair of clamping members 8 that hold and clamp (fix) both side edges of the terminal fitting 4 on the anvil 6.

The ultrasonic horn 7 includes a horn body 71 formed in a relatively wide width and a pressing portion 72 corresponding to an end portion of the ultrasonic horn 7 in the present invention, which is formed in a stepped manner at the end portion of the horn body 71 and presses the core wire 3 against the terminal fitting 4 through the sheathing member 5. That is, the ultrasonic horn 7 sandwiches the terminal fitting 4, the core wire 3, and the sheathing member 5 to be joined between the anvil 6 and the ultrasonic horn 7, and applies ultrasonic vibration by the pressing portion 72 pressing the core wire 3 against the terminal fitting 4 via the sheathing member 5.

The clamping members 8,8 have a substantially rectangular block shape, and are provided at intervals (spans) slightly wider than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7, and are provided so as to be movable up and down in the vertical direction in the same manner as the ultrasonic horn 7. That is, the clamping members 8,8 are released in the raised state, and the terminal fitting 4 is fixed on the anvil 6 by clamping the outer edge of the terminal fitting 4 by the inner edges of the lower surfaces 8a, 8a in the lowered state.

Hereinafter, a method of manufacturing an electric wire with a terminal according to the present embodiment will be described in detail with reference to fig. 2 to 5. In the description of the drawings, for convenience, the distal end side of the core wire 3 is described as "front", and the proximal end side of the core wire 3 is referred to as "rear".

First, as shown in fig. 2 to 4, the terminal fitting 4 is placed on the anvil 6 and clamped. Thereafter, the core wire 3 exposed by removing the insulating coating 2 of the terminal of the electric wire 1 is inserted between the pair of pinching members 8, and then disposed on the proximal end portion of the terminal fitting 4, and then the sheathing member 5 is disposed on the core wire 3 inserted between the pinching members 8, 8.

Subsequently, as shown in fig. 5A and 5B, in a state where the ultrasonic horn 7 is lowered and the core wire 3 is pressed against the terminal fitting 4 by the pressing portion 72 of the ultrasonic horn 7, ultrasonic vibration is applied to the sheathing member 5, the core wire 3, and the terminal fitting 4. At this time, in the pressing portion 72 of the ultrasonic horn 7, the core wire 3 is pressed via the sheathing member 5 in a state in which the entire pressing surface 72a facing the sheathing member 5 including the edge (particularly, the rear edge 72b) orthogonal to the core wire 3 is not in direct contact with the core wire 3 but is in contact with the sheathing member 5 (see fig. 4).

When ultrasonic vibration is applied by pressurization, the protective member 5, the core wire 3, and the terminal fitting 4 are integrally connected, and the electric wire with the terminal is completed. Specifically, as shown in fig. 5A and 5B, in the sheathing member 5 and the core wire 3, in the ultrasonic wave joining region where the ultrasonic vibration is applied by being pressed by the pressing portion 72 of the ultrasonic horn 7, the sheathing member 5 and the core wire 3 are crushed into a flat shape and are integrally joined by the pressing surface 72a of the ultrasonic horn 7. On the other hand, in the non-joining region which is a region on the rear end side of the ultrasonic joining region, the core wire 3 is formed in a tapered shape such that the thickness Wz gradually decreases toward the front end side, and the rear end portion 5a of the sheathing member 5 protruding from the pressing surface 72a of the ultrasonic horn 7 is bent along the tapered core wire 3. Finally, the electric wire with the terminal is taken out by raising the ultrasonic horn 7 and releasing the clamping members 8,8, and the manufacturing of the electric wire with the terminal is completed.

(effects of the embodiment)

Hereinafter, the effect of the electric wire with terminal according to this embodiment will be described in detail.

According to the conventional method of manufacturing an electric wire with a terminal, as shown in fig. 12, the edge 105a of the ultrasonic horn 105 directly contacts the core wire 102. Therefore, at the time of pressing in ultrasonic bonding, stress concentration due to the edge 105a of the ultrasonic horn 105 may occur in the shearing direction of the core wire 102, and a part (strand) 102a of the core wire 102 may be broken (see a partially enlarged view in fig. 12).

In contrast, according to the electric wire with terminal and the manufacturing method thereof of the present embodiment, the sheathing member 5, the core wire 3, and the terminal fitting 4 are connected to each other by ultrasonic vibration applied via the sheathing member 5 in a state where the core wire 3 is sandwiched between the sheathing member 5 and the terminal fitting 4. In other words, at the time of ultrasonic bonding, the core wire 3 is pressurized by the ultrasonic horn 7, which applies ultrasonic vibration via the sheathing member 5, in a state of being protected by the sheathing member 5. Therefore, it is impossible for the ultrasonic horn 7 to directly press the core wire 3, and the edge of the pressing portion 72 of the ultrasonic horn 7 (particularly the rear edge 72b) is impossible to directly contact the core wire 3. As a result, at the time of ultrasonic bonding, the concentration of stress with respect to the core wire 3 due to the edge (particularly, the rear edge 72b) of the pressing portion 72 of the ultrasonic horn 7 can be relaxed, and the disconnection of the core wire 3 can be suppressed.

In the present embodiment, since the width dimension X of the sheathing member 5 is set to be substantially the same as the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7, the core wire 3 can be protected in the width direction of the sheathing member 5 without excess or deficiency. As a result, since the width dimension X of the sheathing member 5 is insufficient, the core wire 3 is not damaged, and the unnecessary material of the sheathing member 5 can be reduced.

Further, in the present embodiment, the lower limit of the width dimension of the sheathing member 5 is obtained by subtracting the diameter D of the strands 3a of the core wire 3 from the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7. Therefore, in the width direction of the sheathing member 5, the strands 3a (all the strands 3a) constituting the core wire 3 overlap with the sheathing member 5, and the strands 3a do not protrude from the sheathing member 5. As a result, the disconnection of the core wire 3 can be effectively suppressed.

In addition, in the present embodiment, since the upper limit of the width dimension of the protective member 5 is set to the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7, the unnecessary portion of the protective member 5 is reduced, and the yield of the material of the protective member 5 can be improved. As a result, the manufacturing cost of the electric wire with the terminal can be reduced.

In the present embodiment, since the depth dimension Y of the sheathing member 5 is set to be larger than the depth dimension Wy of the pressing portion 72 of the ultrasonic horn 7, it is impossible for the pressing portion 72 (particularly the rear edge 72b) of the ultrasonic horn 7 to directly press the core wire 3 on the proximal end side of the core wire 3. As a result, the disconnection of the core wire 3 can be suppressed more effectively.

Further, in the present embodiment, since the thickness dimension Z of the sheathing member 5 is set to be at least equal to or greater than the diameter D of the strands 3a of the core wire 3, the sheathing member 5 can withstand the shearing force that each of the strands 3a of the core wire 3 can receive at least from the pressing portion 72 of the ultrasonic horn 7. In other words, the sheathing member 5 may ensure rigidity capable of withstanding the shearing force that each strand 3a of the core wire 3 may receive from the pressing portion 72 of the ultrasonic horn 7. As a result, the disconnection of the core wire 3 can be further effectively suppressed by the sheathing member 5.

Further, in the present embodiment, since the sheathing member 5 is formed of the same material as the core wire 3, a good connection between the sheathing member 5 and the core wire 3 can be obtained by ultrasonic bonding, and the sheathing member 5 and the core wire 3 can be more firmly connected.

(modification example)

Although the terminal fitting 4 is simply formed in a flat plate shape in the present embodiment, the terminal fitting 4 may have an ultrasonic wave connection region formed in a U-shaped cross section, i.e., a connection region 4a with the core wire 3, as shown in fig. 6A and 6B.

As described above, since the connection region 4a having the core wire 3 is formed in the U-shaped cross section, the ultrasonic bonding can be performed in a state where the positional deviation in the width direction of the core wire 3 and the sheathing member 5 is suppressed, and the productivity and quality of the electric wire having the terminal can be improved.

[ second embodiment ]

Fig. 7A, 7B and 8 show a second embodiment of an electric wire with a terminal and a method of manufacturing the same according to the present invention. In the present embodiment, the configuration of the protective member 5 according to the first embodiment is modified, and the other configurations are the same as those of the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in fig. 7A, 7B, and 8, in the present embodiment, the width dimension X of the protective member 5 is set to be greater than or equal to 2/3 of the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7 and smaller than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7. In the side surface of the core wire 3 facing the sheathing member 5, chamfered portions 5b having, for example, an R-tapered shape (arc-shaped in cross section) are formed on both side edges in the width direction (X direction). The chamfered portion 5b may be formed not only in an R-tapered shape but also in a chamfered shape (linear in cross section), for example.

Here, when the core wire 3 is crushed by the ultrasonic horn 7 at the time of pressurization accompanying ultrasonic bonding, stress concentration may occur in a region in the width direction (X direction) having a large crushing margin, that is, in a central portion of the pressing portion 72 of the ultrasonic horn 7 and in a region of 2/3 of the width dimension Wx of the pressing portion 72.

Therefore, in the present embodiment, the lower limit of the width dimension of the protective member 5 is set to 2/3 of the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7. As a result, it is possible to protect the region where stress concentration is likely to occur with the protective member 5 while suppressing the material cost of the protective member 5. As a result, disconnection of the core wire 3 can be suppressed, and the manufacturing cost (material cost of the sheathing member 5) can be reduced.

Further, in the present embodiment, since the width dimension X of the sheathing member 5 is set to be equal to or greater than 2/3 of the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7 and smaller than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7, the sheathing member 5 can be shared with respect to the core wire 3 within a predetermined range in which the width dimension after joining is relatively large. Therefore, it is not necessary to manufacture the protective member 5 in accordance with the width dimension after the joining of the core wires 3 (for each width dimension after the joining), and the productivity of the electric wire with the terminal can be improved and the manufacturing cost can be reduced.

As described above, in the present embodiment, the width X of the sheathing member 5 is set smaller than the width Wx of the pressing portion 72 of the ultrasonic horn 7, and both side edges of the sheathing member 5 can press the core wire 3 in the direction parallel to the core wire 3.

Therefore, in the present embodiment, the chamfered portions 5b are provided on both side edges in the width direction (X direction) of the side surface of the sheathing member 5 facing the core wire 3. Therefore, stress concentration due to both side edges in the width direction (X direction) of the protective member 5 can be suppressed, and damage to the core wires 3 can also be suppressed in the direction parallel to the core wires 3.

(modification example)

Although the compression margin of the core wire 3 is relatively small and the sheathing member 5 is laminated on the core wire 3 in the present embodiment, for example, as shown in fig. 9A and 9B, the compression margin of the core wire 3 by the ultrasonic horn 7 may be large until the sheathing member 5 is embedded in the concavely deformed core wire 3.

[ third embodiment ]

Fig. 10 and 11 show an electric wire with a terminal according to a third embodiment of the present invention. In the present embodiment, the configuration of the protective member 5 according to the first embodiment is modified, and the other configurations are the same as those of the first embodiment. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in fig. 10 and 11, in the present embodiment, the width dimension X of the protective member 5 is set larger than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7. Based on the dimensional difference, the unnecessary side portions 5d, 5d of the sheathing member 5 that exceed the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7 are bent toward the side opposite to the core wire 3 (pressing portion 72 side). That is, when the sheathing member 5 is pushed between the clamping members 8,8 by the pressing portion 72 of the ultrasonic horn 7, the central flat portion 5c is connected (joined) to the core wire 3 in a state where both side portions 5d, 5d are sandwiched between the pressing portion 72 of the ultrasonic horn 7 and the inner upper edges 8b, 8b of the clamping members 8, respectively, and are bent to the opposite side (pressing portion 72 side) with respect to the core wire 3. In this way, the sheathing member 5 is bent into a concave shape by the ultrasonic horn 7 along the outer shape of the tip portion of the pressing portion 72 of the ultrasonic horn 7, and the central flat portion 5c is integrally connected to the core wire 3 (see fig. 10).

In the present embodiment, since the width dimension X of the sheathing member 5 is set to be larger than the width dimension Wx of the pressing portion 72 of the ultrasonic horn 7, the sheathing member 5 can be shared with respect to the core wire 3 within a predetermined range in which the width dimension after joining is relatively small. Therefore, it is not necessary to manufacture the protective member 5 in accordance with the width dimension after the joining of the core wires 3 (for each width dimension after the joining), and the productivity of the electric wire with the terminal can be improved and the manufacturing cost can be reduced.

The present invention is not limited to the configurations illustrated in the above-described embodiments, and may be freely changed according to the specification of the application target or the like without departing from the spirit of the present invention.

Further, in each of the embodiments described above, the plate-like member is shown and described as the protective member according to the present invention, but the present invention is not limited to such a plate-like member, and may take other forms such as being formed in a gentle arc shape as long as ultrasonic bonding can be performed on the electric wire.