JP2020136204A - Wire connection method - Google Patents

Abstract

To provide a wire connection method capable of reliably joining conductors of different metal types in which the conductors are coated with an insulation coating by applying ultrasonic vibration to the plurality of conductors of coated wires disposed along a longitudinal direction.SOLUTION: A multiple types of metal conductors 3 having different compressive deformability due to a predetermined compressive force are joined by performing a pre-compression step (step s3) of compressing to a predetermined compression rate with a first compression force and a joining step (steps s6 to s8) of applying ultrasonic vibration while applying a second compressive force smaller than the first compressive force to the compressed conductors 3 to ultrasonically join the conductors 3. In the pre-compression step, the plurality of conductors 3 compresses aluminum alloy conductors 3 having high compressive deformability at a compression rate of 65% or more.SELECTED DRAWING: Figure 3

Description

The present invention relates to an electric wire connecting method for joining conductors such as core wires and stranded wires in a plurality of coated electric wires constituting a wire harness for an automobile.

An electric device installed in an automobile or the like is connected to another electric device or a power supply device via a wire harness in which a plurality of covered electric wires are bundled to form an electric circuit. At this time, the wire harness and the electrical equipment or power supply device are connected to each other by the connectors attached to each.

As a method of connecting a plurality of coated electric wires constituting the above-mentioned wire harness, for example, as described in Patent Document 1, the conductors of the plurality of coated electric wires are bundled and ultrasonic vibration is applied to make ultrasonic waves. The method of joining is used. Specifically, a horn (compressive vibration part) in which the conductors of a plurality of coated electric wires are bundled and arranged on an anvil (conductor arrangement part) which is a conductor receiving part for receiving a conductor and an ultrasonic vibration is applied is anvil (conductor arrangement part). It is ultrasonically bonded by abutting the bundled conductors arranged in the part).

With the recent diversification, it has become possible to join coated electric wires having different metal types of conductors so as to join aluminum-coated electric wires having an aluminum alloy conductor and copper-coated electric wires having a copper alloy conductor. It has been
Even if ultrasonic vibrations are applied to conductors of dissimilar metals in this way for ultrasonic bonding, conductors of different metal types may not be able to be reliably bonded because they have different thermal conductivity, deformability, and melting temperature. was there.

Japanese Unexamined Patent Publication No. 2000-188018

The present invention is an electric wire connecting method in which a conductor is coated with an insulating coating, and ultrasonic vibration is applied to the conductors of a plurality of the coated electric wires arranged along the longitudinal direction to reliably join the conductors of different metal types. The purpose is to provide.

In the present invention, a plurality of coated electric wires whose conductors are coated with an insulating coating are arranged along the longitudinal direction, and the conductors of the plurality of the coated electric wires arranged along the longitudinal direction are connected by an electric wire connecting device. In the connection method, a compression step of compressing a plurality of the conductors with a predetermined first compressive force so as to have a predetermined compression ratio, and a second compressive force smaller than the first compressive force on the compressed conductors. A joining step of ultrasonically joining a plurality of the conductors by applying ultrasonic vibration while acting is performed, and the plurality of the conductors are made of a plurality of types of metal conductors having different compressive deformability due to a predetermined compressive force. Yes, the predetermined compression rate for compressing the plurality of the conductors in the compression step is the compression rate at which the conductor of the metal type having the highest compressive deformability among the plurality of conductors is compressed at a compression rate of 65% or more. It is characterized by being.

The conductor may be, for example, a stranded wire obtained by twisting a plurality of conductive strands such as an aluminum strand, an aluminum alloy strand, a copper strand, or a copper alloy strand, or a single conductive wire. It is a concept that includes. In the case of a stranded wire, it may be a stranded wire composed of a single metal type strand or a stranded wire in which a plurality of metal grade strands are mixed.

The above-mentioned compressibility is the ratio of the cross-sectional area of the conductor after compression deformation to the cross-sectional area of the conductor before compression.
Therefore, the above-mentioned bulk modulus of 65% or more means that the cross section of the conductor before compression becomes 65% or more after compression deformation.
The above-mentioned highest compressive deformability refers to a conductor of a metal type that is most easily deformed by a predetermined compressive force among a plurality of conductors having different compressive deformability.

The plurality of types of metal conductors may be two types of metal conductors having different compressive deformability due to a predetermined compressive force, or may be three or more types of metal conductors. Further, even if the metal types are different, if the compressive deformability is the same, they are regarded as the same type in the present specification.

According to the present invention, the conductors having different metal types can be reliably joined.
More specifically, a compression step of compressing a plurality of the conductors with a predetermined first compressive force to a predetermined compressibility, and applying a second compressive force smaller than the first compressive force to the compressed conductors. The compression is performed to join a plurality of metal conductors having different compressive deformability due to a predetermined compressive force by performing a joining step of ultrasonically joining a plurality of the conductors while applying ultrasonic vibrations. Since the predetermined compressibility for compressing the plurality of the conductors in the step is set to the compressibility at which the conductor of the metal type having the highest compressive deformability is compressed at a compressibility of 65% or more among the plurality of conductors. The contact area between the conductors can be secured, and ultrasonic bonding can be performed reliably. Further, since the contact area between the conductors can be secured, the conductors can be reliably joined with a small amount of thermal energy, that is, a small amount of ultrasonic vibration energy.

Furthermore, when only the bonding step of ultrasonically bonding a plurality of types of conductors having different compressive deformability without going through the compression step, the deformation difference becomes large between the conductors having different compressive deformability in the bonding step, and the compressive deformability becomes large. Only conductors of high metal species are overbonded, but conductors of metal species with the highest compressive deformability are pre-compressed in a compression step so as to have a compression ratio of 65% or more, that is, predetermined. Since ultrasonic vibration is applied to conductors compressed at the compression rate of, the deformation difference can be reduced between conductors with different compressive deformability in the bonding process, and ultrasonic waves can be obtained between conductors with different compressive deformability. Can be joined.

As an aspect of the present invention, the predetermined compressibility may be a compressibility in which the conductor of the metal type having the lowest compressive deformability among the plurality of conductors is compressed at a compressibility of 90% or less.
The above-mentioned lowest compressive deformability refers to a conductor of a metal type that is most difficult to be deformed by a predetermined compressive force among a plurality of conductors having different compressive deformability.
The above-mentioned compressibility of 90% or less means that the cross section of the conductor before compression becomes 90% or less after compression deformation.

According to the present invention, conductors having different compressive deformability can be joined more reliably and efficiently.
More specifically, in the compression step, the conductor of the metal type having the highest compressive deformability is compressed at a compression rate of 65% or more, and the conductor of the metal type having the lowest compressive deformability is compressed at a compression rate of 90% or less. Therefore, all the conductors having different compressive deformability are compressed, and the contact area between the conductors can be secured, so that the conductors can be joined more efficiently and reliably.

Further, as an aspect of the present invention, in the compression step, a compression vibration unit that applies ultrasonic vibration of the wire connection device to a plurality of the conductors arranged in the conductor arrangement portion of the wire connection device is provided. It is moved to a compression relative position based on the compression ratio, and in the joining step, ultrasonic vibration is applied while applying the second compressive force to the conductor until the compression vibrating portion reaches the joining relative position with respect to the conductor. The first joining step of applying and joining the conductor, and after the compression vibrating portion reaches the joining relative position, the joining relative position is maintained, and the compressive force acting on the conductor is obtained from the second compressive force. The second joining step of joining the conductors by applying ultrasonic vibration while lowering the conductors may be performed.

The above-mentioned compression relative position and bonding relative position with respect to the conductor are positions where the compression vibration unit can make ultrasonic bonding by applying ultrasonic vibration to a plurality of the conductors arranged in the conductor arrangement portion of the electric wire connecting device. It is performed by controlling the position of the conductor that has been compressed and ultrasonically bonded to maintain its position, and by controlling the change in position of the conductor that is compressed by ultrasonic bonding.

According to the present invention, the second compressive force is applied to a plurality of conductors compressed at a predetermined compression rate until the compression vibrating portion is in a joint relative position with respect to the conductor in the first joining step. The conductor is joined by applying ultrasonic vibration while acting on the conductor, and in the second joining step, the compressive force acting on the conductor is applied by the compressive vibrating portion maintained at the joining relative position. 2 Since the conductors are joined by applying ultrasonic vibration while lowering the compressive force, the deformation of the conductors to be ultrasonically joined can be controlled, the influence of material variation of the conductors is reduced, and the robustness of the joining conditions is improved. can do.

Further, as an aspect of the present invention, the compressive force of the compression vibrating portion moved to the compression relative position in the compression step is reduced to a third compressive force smaller than the second compression force before the joining step. You may.
According to the present invention, compressed conductors can be joined more reliably.

More specifically, the compressive force of the compressive vibrating portion acting on the conductor before the joining step after the completion of the compression step of compressing the bundled conductor with a predetermined first compressive force larger than the second compressive force. By temporarily reducing the compressive force to a predetermined third compressive force, which is smaller than the second compressive force, and then increasing the compressive force to the second compressive force while applying ultrasonic vibration, the load acting on the compressed conductor is reduced and more. Can be reliably joined.

Further, as an aspect of the present invention, one of the plurality of the conductors is composed of aluminum or an aluminum alloy, and the other of the plurality of the conductors is composed of copper or a copper alloy, so that the metal species having high compressive deformability is used. It may be aluminum or an aluminum alloy.
According to the present invention, a conductor made of aluminum or an aluminum alloy and a conductor made of copper or a copper alloy can be reliably joined.

More specifically, it is difficult to join a conductor made of aluminum or an aluminum alloy and a conductor made of copper or a copper alloy because the hardness and thermal conductivity are different and the melting temperature is also different. However, in the compression step, the conductor made of aluminum or an aluminum alloy is compressed as the conductor having high compressive deformability at a compression rate of 65% or more, and then the joining step is performed, so that the contact area between the conductors is secured. , Can be reliably joined.

Further, as an aspect of the present invention, a plurality of the conductors may be inserted into a conductive tubular body, the plurality of conductors may be compressed together with the tubular body in the compression step, and ultrasonically bonded in the bonding step. Good.

According to the present invention, the conductors of different metal types can be reliably joined while the conductors are restricted by the tubular body. Further, since the conductor is regulated by the tubular body, it is possible to prevent the conductor to be joined from sticking to the compression vibration portion or the conductor arrangement portion.

According to the present invention, there is provided an electric wire connecting method in which a conductor is coated with an insulating coating and ultrasonic vibration is applied to a plurality of the conductors arranged along the longitudinal direction to reliably join the conductors of different metal types. can do.

Explanatory drawing about the coated electric wire to be joined. Schematic block diagram of the wire connection device. Flowchart of electric wire connection method. Schematic diagram of the main part of the electric wire connecting device. Schematic diagram of the joining operation of the main part of the electric wire connecting device. Relationship between the compressive force of the horn and the relative position with respect to the conductor in the wire connection device The figure explaining the compression deformation of a conductor in a joining process with and without a pre-compression process. Table of the results of the demonstration experiment. The graph which shows the relationship between the compressive force and the relative position of a horn with respect to a conductor in the electric wire connection apparatus of another embodiment.

An embodiment of the present invention will be described in detail below with reference to the drawings.
FIG. 1 shows an explanatory view of a coated electric wire 1 to be joined, and in detail, FIG. 1A shows a plan view of a state in which a plurality of coated electric wires 1 to be joined are arranged in parallel, and FIG. 1B shows a plan view. FIG. 1 (c) shows a plan view of a state in which conductors 3 of a plurality of covered electric wires 1 arranged in parallel are bundled, and FIG. 1 (c) shows a plan view of a state in which a joint tube 4 is attached to the bundled conductors 3. d) shows a plan view of a joined electric wire 1a formed by joining conductors 3 of a plurality of covered electric wires 1.

Further, FIG. 2 shows a schematic block diagram of the electric wire connecting device 10, and FIG. 3 shows a flowchart of an electric wire connecting method.
FIG. 4 shows a schematic explanatory view of the main portion 10a of the electric wire connecting device 10, and in detail, FIG. 4A shows a schematic state in which the joint pipe 4 is arranged with respect to the conductors 3 of the plurality of covered electric wires 1 arranged in parallel. A perspective view is shown, FIG. 4B shows a schematic perspective view of a state in which conductors 3 of a plurality of covered electric wires 1 arranged in parallel are bundled and mounted inside a joint pipe 4, and FIG. 4C shows an electric wire connecting device. A schematic perspective view of a state before arranging the plurality of coated electric wires 1 with respect to the main portion 10a of the wire 10 is shown, and FIG. The schematic perspective view of is shown.

FIG. 5 shows a schematic explanatory view of the joining operation of the main portion 10a of the electric wire connecting device 10, and FIG. 5 (a) shows a cross section of the covered electric wire 1 arranged with respect to the main portion 10a of the electric wire connecting device 10. FIG. 5 (b) shows a cross-sectional view of a state in which the horn 12 and the restricting portion 13 are moved in a direction close to the anvil 11 constituting the main portion 10a of the electric wire connecting device 10, and FIG. 5 (c) is shown. ) Shows a cross-sectional view of a state in which the horn 12 precompresses a plurality of conductors 3 with the first compressive force, and FIG. The figure is shown.

FIG. 6 is a graph showing the relationship between the compressive force of the horn 12 and the relative position with respect to the conductor 3 in the electric wire connecting device 10, and FIG. 7 shows a diagram for explaining the compressive deformation of the conductor 3 in the joining process depending on the presence or absence of the precompression process. , FIG. 8 is a table showing the results of the demonstration experiment.

In the electric wire connecting method of the present invention described below, a plurality of coated electric wires 1 in which the conductor 3 is coated with the insulating coating 2 are arranged along the longitudinal direction L, and a plurality of coated electric wires arranged along the longitudinal direction L. A joint tube 4 is attached to the conductor 3 of 1, and ultrasonic vibration is applied while applying a second compressive force to join the plurality of conductors 3 to form a joined electric wire 1a joined by the conductor joining portion 3a. This method is performed by using the electric wire connecting device 10 described later.

The coated electric wire 1 to be joined is a coated electric wire composed of a conductor 3 which is a stranded wire obtained by twisting a plurality of strands and an insulating coating 2 which covers the outside of the conductor 3.
At least one conductor 3 of the plurality of coated electric wires 1 is a stranded wire made of an aluminum alloy strand, and the conductor 3 of the other coated electric wire 1 is composed of a stranded wire made of a copper alloy strand. There is. That is, the plurality of conductors 3 to be joined are dissimilar metal joints.

In order to join the plurality of conductors 3 configured in this way, as shown in FIG. 1, three coated electric wires 1 along the longitudinal direction L are arranged in parallel in the width direction, and three coated electric wires 1 are arranged in parallel. The coated electric wire 1 is arranged above between the coated electric wires 1, and a total of five coated electric wires 1 are arranged, the conductors 3 are bundled with each other, and the joint pipe 4 is attached.

The conductor 3 is exposed at the tip of the coated wire 1 by stripping the insulating coating 2 at the tip of the covered wire 1.
Further, the joint pipe 4 is a metal pipe made of a conductive metal, which has a space inside in which conductors 3 of a plurality of coated electric wires 1 can be bundled and inserted.

Then, in the electric wire connecting device 10 described later, ultrasonic vibration is applied to the bundled conductors 3 of the five covered electric wires 1 arranged as described above, and the conductor joint portion 3a is formed inside the joint pipe 4 by ultrasonically joining the conductors 3. It constitutes a bonded electric wire 1a in which a plurality of covered electric wires 1 are electrically and physically bonded via a conductor joint portion 3a.

As shown in FIG. 4C, the electric wire connecting device 10 for joining the plurality of conductors 3 to form the joined electric wire 1a is attached to the anvil 11 on which the plurality of conductors 3 are arranged and the conductor 3 placed on the anvil 11. On the other hand, the horn 12 that causes ultrasonic vibration to act on the conductor 3 in close proximity from above, and the regulation unit 13 that moves in the width direction W along the bottom surface of the horn 12 to regulate the width direction W of the plurality of conductors 3. It has a main part 10a composed of and.

Further, as shown in FIG. 2, the electric wire connecting device 10 includes an ultrasonic vibration generating unit 21 that ultrasonically vibrates the horn 12 constituting the main unit 10a, a horn driving unit 22 that moves the horn 12 in the vertical direction, and a regulating unit. The jaw drive unit 23 that moves 13 in the width direction W is connected to the ultrasonic vibration generation unit 21, the horn drive unit 22, and the jaw drive unit 23, and the ultrasonic vibration generation unit 21, the horn drive unit 22, and the jaw drive unit 23 are connected. A control unit 24 for controlling the above and a time measuring unit 25 connected to the control unit 24 are provided.

The electric wire connecting device 10 configured in this way controls ON / OFF of the ultrasonic vibration of the horn 12 by being controlled by the control unit 24, moves the horn 12 up and down at a variable predetermined pressure, and moves the horn 12 up and down. Bottom dead point in downward movement (conductor 3 made of aluminum alloy with high compressibility in conductor 3 has a compressibility of 65% or more, and conductor 3 made of copper alloy with low compressibility has a compressibility of 90% or less. It is possible to stop the movement at the bottom dead point at the time of compression or the bottom dead point at the time of joining, which is the compressibility to be performed, that is, to control the bottom dead point.

That is, the control unit 24 compresses the conductors 3 bundled and arranged in the anvil 11 by applying a first compressive force with the horn 12, or applies ultrasonic vibration while compressing with the second compressive force to apply ultrasonic vibration to the horn. When the 12 is in a predetermined position, the horn 12 maintained at the position is programmed to apply ultrasonic vibration while applying a predetermined compressive force to the bundled conductors 3.

Further, the control unit 24 is connected to the time measuring unit 25, and controls the driving of the ultrasonic vibration generating unit 21, the horn driving unit 22, and the jaw driving unit 23 according to the time and time measured by the time measuring unit 25. Can be done.

Subsequently, with reference to the flowchart shown in FIG. 3, the electric wire connecting method of the coated electric wire 1 using the electric wire connecting device 10 will be described below. In this embodiment, a case where five coated electric wires 1 having a conductor 3 made of an aluminum alloy and five coated electric wires 1 having a conductor 3 made of a copper alloy are joined will be described together with FIGS. 4 to 6.

In FIG. 5, the positions of the horn 12 and the regulation unit 13 in the previous process are shown by broken lines. Further, FIG. 6 is a graph showing the relationship between the compressive force of the horn 12 with respect to the conductor 3 in each step described later and the height of the horn 12 moving downward in the electric wire connecting device 10, and the horn 12 is shown in the graph of FIG. The part that is ultrasonically vibrating is shown by a thick line.

The insulating coating 2 at the tip of the coated electric wire 1 is peeled off to expose the conductor 3 to a predetermined length, and the conductors 3 of the coated electric wires 1 in which a plurality of the conductors 3 are arranged in parallel are bundled (see FIGS. 1 (b) and 4 (a)). The bundled conductors 3 are attached to the joint pipe 4 (see FIGS. 1 (c) and 4 (b), step s1).

As shown in FIGS. 4 (d) and 5 (a), a plurality of covered electric wires 1 in which the joint pipe 4 is attached to the bundled conductor 3 are arranged on the upper surface of the anvil 11 (step s2).
Then, as shown in FIG. 5B, the regulating portion 13 is moved inward in the width direction W along the bottom surface of the horn 12, and the horn 12 is moved downward together with the regulating portion 13 so as to approach the anvil 11.

Further, as shown in FIG. 5C, the restricting portion 13 is moved along the bottom surface of the horn 12 to the inside of the width direction W until the inner side surface of the restricting portion 13 in the width direction W abuts on the side surface of the anvil 11. The regulation unit 13 is moved and controlled by the control unit 24 until the horn drive unit 22 is operated to compress the conductor 3 to which the joint tube 4 is mounted with a first compression force higher than the second compression force described later. The horn 12 is moved downward together with (step s3: precompression step).

In the pre-compression step (step s3) of the conductor 3 by the horn 12, the horn 12 continues until the conductor 3 arranged in the anvil 11 moves to the bottom dead center during compression (step s4: No).

Of the conductors 3 to which the joint tube 4 is mounted, the conductor made of aluminum alloy having high compressive deformability has a compressibility of 65% or more, and the conductor made of copper alloy having low compressive deformability is compressed at a bulk modulus of 90% or less. When the downward movement of the horn 12 reaches the bottom dead point at the time of compression (step s4: Yes), the control unit 24 controls the horn drive unit 22 to reduce the compressive force of the horn 12 to a second, which will be described later. The compressive force is reduced to a third compressive force lower than the compressive force (see FIG. 6). As shown in FIG. 6, the horn 12 in which the compressive force (first compressive force) is reduced from the third compressive force temporarily rises from the bottom dead center during compression as the compressive force decreases.

That is, in the horn 12 in which the compressive force on the conductor 3 arranged in the anvil 11 is reduced, the control unit 24 controls the ultrasonic vibration generating unit 21 and the horn driving unit 22 to ultrasonically vibrate the horn 12 (step). Together with s5), ultrasonic bonding is performed while compressing the conductor 3 with a second compressive force lower than the first compressive force and higher than the third compressive force (step s6: first bonding step).

As described above, as shown in FIG. 5D, in the compression bonding in which the conductor 3 is ultrasonically bonded while being compressed by the second compressive force lower than the first compressive force and higher than the third compressive force, the horn 12 is used. It continues until it moves to the bottom dead point at the time of bonding, which is a predetermined position with respect to the conductor 3 arranged in the anvil 11 (step s7: No).

When the downward movement of the horn 12 reaches the bottom dead point at the time of bonding (step s7: Yes), the control unit 24 controls the horn drive unit 22 to stop the downward movement of the horn 12 and starts the timing of the timing unit 25. Then, until a predetermined time elapses (step s8: No), the ultrasonic vibration generating unit 21 and the horn driving unit 22 are controlled to reduce the second compressive force by the horn 12 that ultrasonically vibrates at the bottom dead point at the time of bonding. The conductor 3 is ultrasonically bonded (second bonding step).

When a predetermined time elapses (step s8: Yes) in which the horn 12 ultrasonically vibrates at the bottom dead point at the time of bonding applies a second compressive force, the conductors 3 are ultrasonically bonded to each other inside the joint tube 4. A joint 3a (see FIG. 1D) can be configured. In this way, it is possible to form a bonded electric wire 1a in which a plurality of coated electric wires 1 are bonded via a conductor bonding portion 3a in which the conductors 3 are ultrasonically bonded to each other.

As described above, as an electric wire connection method in which a plurality of coated electric wires 1 in which the conductor 3 is covered with the insulating coating 2 are arranged along the longitudinal direction L and a plurality of conductors 3 arranged along the longitudinal direction L are joined. A pre-compression step (step s3) of compressing a plurality of conductors 3 with a predetermined first compressive force so as to have a predetermined compression ratio, and applying a second compressive force smaller than the first compressive force to the compressed conductors 3. A joining step (steps s6 to s8) of ultrasonically joining a plurality of conductors 3 by applying ultrasonic vibration while allowing them to act is performed, and the plurality of conductors 3 have a plurality of types having different compressive deformability due to a predetermined compressive force. The metal conductor 3 has a predetermined compression ratio for compressing the plurality of conductors 3 in the precompression step (step s3), and 65% of the plurality of conductors 3 is made of an aluminum alloy having high compressive deformability. Since the compression ratio is set to be compressed at the above compression ratio, conductors 3 of different metal types can be reliably joined.

More specifically, a precompression step (step s3) of compressing a plurality of conductors 3 with a predetermined first compressive force so as to have a predetermined compression ratio, and a second compression force smaller than the first compressive force of the compressed conductors 3. A joining step (steps s6 to s8) of ultrasonically joining a plurality of conductors 3 by applying ultrasonic vibration while applying a compressive force is performed, and a plurality of types of metals having different compressive deformability due to a predetermined compressive force are made. In order to join the conductors 3 of the above, a predetermined compression ratio for compressing the plurality of conductors 3 in the precompression step (step s3) is set, and among the plurality of conductors 3, the conductor 3 made of an aluminum alloy having high compressive deformability is 65. Since the compression rate is set to be compressed at a compression rate of% or more, the contact area between the conductors 3 can be secured, and ultrasonic bonding can be reliably performed. Further, since the contact area between the conductors 3 can be secured, the conductors 3 can be joined with a small amount of thermal energy, that is, a small amount of ultrasonic vibration energy.

Furthermore, as shown in FIG. 7, only the bonding step (step) of ultrasonically bonding a plurality of types of conductors 3 having different compressive deformability while applying a first compressive force without going through the pre-compression step (step s3). When s6 to s8) are performed, the deformation difference becomes large between the conductors 3 having different compressive deformability in the joining step (steps s6 to s8), and only the conductors 3 made of aluminum alloy having high compressive deformability are overbonded. ..

On the other hand, since the conductor 3 made of an aluminum alloy having high compressive deformability is pre-compressed in the pre-compression step (step s3) so as to have a compressibility of 65% or more, that is, a predetermined compressibility (aluminum). Since the alloy conductor 3 is ultrasonically bonded by applying ultrasonic vibration to the conductor 3 compressed at a compressibility of 65% or more), the conductors 3 having different compressive deformability in the bonding steps (steps s6 to s8) The deformation difference can be reduced between the conductors, and the conductors 3 having different compressibility deformability can be ultrasonically joined.

Further, in the pre-compression step, among the plurality of conductors 3, the conductors 3 made of copper alloy having low compressive deformability have a compressibility of 90% or less, so that the conductors 3 having different compressive deformability are compressed with each other. Can be joined more reliably and efficiently.

More specifically, in the pre-compression step (step s3), the conductor 3 made of an aluminum alloy having high compressive deformability is compressed at a bulk modulus of 65% or more, and the conductor 3 made of copper alloy having low compressive deformability is 90. Since it is compressed at a bulk modulus of% or less, all conductors 3 having different compressive deformability are compressed, and the contact area between the conductors 3 can be secured, so that the conductors 3 can be joined more efficiently and reliably. it can.

Here, the result of the demonstration experiment of the compression ratio in the above-mentioned pre-compression step (step s3) will be described with reference to FIG.
As a demonstration experiment, the conductors of three 2.0sq copper alloy coated electric wires and the conductors of three 2.0sq aluminum alloy coated electric wires are each compressed at a predetermined compression rate and then a predetermined pressing force. The resistance value after ultrasonic bonding was measured by ultrasonic bonding under the above. The evaluation results are shown in Table 8 when the resistance value between the electric wires is 0.5 mΩ or less as “◯” and when the resistance value between the electric wires is larger than 0.5 mΩ as “x”. In Table 8, the upper side shows the case of strong compression (when the compression rate value is low), and the right side shows the case where the pressing force at the time of ultrasonic bonding is high.

As can be seen from Table 8, it was confirmed that the conductor 3 made of aluminum alloy has a large resistance value between the electric wires when the pressing force is high or the compressibility is 60%, and the conductor 3 made of copper alloy is It was confirmed that the resistance value between the wires increases when the pressing force is low or when the compression rate is 100%, that is, when there is no compression.
On the other hand, when the compressibility was 65% or more and 90% or less, it was confirmed that the resistance value between the electric wires of both the aluminum alloy conductor 3 and the copper gold conductor 3 became small.

From this, when the compression rate is higher than 65% (the compression rate value is lower), the aluminum alloy conductor, which has higher compressive deformability than the copper alloy conductor, tends to be defective, and the compression rate is higher than 90%. When it becomes low (the compression ratio becomes high), the conductor made of copper alloy, which has lower compressive deformability than the conductor made of aluminum alloy, tends to be defective, and the compression ratio is precompressed at 65% or more and 90% or less. , It was confirmed that both the copper alloy conductor and the aluminum alloy conductor were generally good. More preferably, it is 70% or more and 85% or less.

Further, in the pre-compression step (step s3), the horn 12 that compresses the plurality of conductors 3 received in the anvil 11 while applying ultrasonic vibration is subjected to a predetermined compressive force while applying a first compressive force. In the joining step (steps s6 to s8), the horn 12 that moves to the bottom dead point during compression (the position where the above-mentioned compression ratio is obtained) and applies the ultrasonic vibration of the electric wire connecting device 10 is arranged in the anvil 11. The first joining step (step) of joining the plurality of conductors 3 by applying ultrasonic vibration while applying a second compressive force to the plurality of conductors 3 until the bottom dead point at the time of joining is reached. After s6 to s7) and the horn 12 reach the bottom dead point at the time of joining, the bottom dead point at the time of joining is maintained, and ultrasonic vibration is performed while reducing the compressive force acting on the plurality of conductors 3 from the second compressive force. By performing the second joining step (step s8) of imparting and joining the plurality of conductors 3, the deformation of the conductor 3 to be ultrasonically joined can be controlled, the influence of the material variation of the conductor 3 and the like can be reduced, and the joining conditions can be reduced. Can improve the robustness of.

Further, in the pre-compression step (step s3), a compressive force reducing step of reducing the compressive force of the horn 12 moved to the bottom dead point during compression to a third compressive force smaller than the second compressive force is performed in the joining step (step s6). Since it is performed before s8), the compressed conductor 3 can be joined more reliably.

More specifically, it acts on the conductor 3 before the joining step (steps 6 to s8) after the pre-compression step (step s3) of compressing the conductor 3 bundled with a predetermined first compressive force larger than the second compressive force. The compressive force of the horn 12 to be made is once reduced to a predetermined third compressive force smaller than the second compressive force, and then increased to the second compressive force while applying ultrasonic vibration to form the compressed conductor 3. It is possible to join more reliably while reducing the acting load.

Further, since any one of the plurality of conductors 3 is made of an aluminum alloy and the other of the plurality of conductors 3 is made of a copper alloy, and the metal type having high compressive deformability is an aluminum alloy, it is made of an aluminum alloy. The conductor 3 and the conductor 3 made of a copper alloy can be reliably joined.

More specifically, the conductor 3 made of an aluminum alloy and the conductor 3 made of a copper alloy have different hardness and thermal conductivity, and also have different melting temperatures. Therefore, only the joining step is performed. It is difficult to join. On the other hand, in the precompression step (step s3), the conductor 3 made of an aluminum alloy is compressed as a conductor 3 having high compressive deformability at a compressibility of 65% or more, and then the joining step (steps 6 to s8) is performed. Therefore, the contact area between the conductors 3 can be secured and the conductors can be reliably joined.

Further, a plurality of conductors 3 are inserted into the conductive joint pipe 4, and the plurality of conductors 3 are compressed together with the joint pipe 4 in the precompression step (step s3) and superbrowned in the bonding step (steps 6 to s8). Since ultrasonic bonding is performed, conductors 3 of different metal types can be reliably bonded while the conductor 3 is regulated by the joint pipe 4. Further, since the conductor 3 is regulated by the joint pipe 4, it is possible to prevent the conductor 3 to be joined from sticking to the horn 12 or the anvil 11.

In correspondence between the configuration of the present invention and the embodiment,
In the connecting device of the present invention, the conductor of the above-described embodiment corresponds to the conductor 3, and so on.
The insulation coating corresponds to the insulation coating 2,
The covered wire corresponds to the covered wire 1,
The compression step corresponds to the pre-compression step (step s3).
The joining process corresponds to the joining process (steps s6 to s8).
The conductor of the metal type with the highest compressive deformability corresponds to the conductor 3 made of aluminum alloy.
The conductor of the metal type with the lowest compressive deformability corresponds to the conductor 3 made of copper alloy.
The conductor arrangement part corresponds to the anvil 11 and
The compression vibration part corresponds to the horn 12,
The relative position of the joint corresponds to the bottom dead center at the time of joining,
The compression relative position corresponds to the bottom dead center during compression,
The electric wire connection device corresponds to the electric wire connection device 10.
Although the tubular body corresponds to the joint tube 4,
The present invention is not limited to the configuration of the above-described embodiment, and can be applied based on the technical idea shown in the claims, and many embodiments can be obtained.

For example, the horn drive unit 22 is configured by a position-controllable drive system capable of moving the horn 12 to a predetermined position, and the horn 12 is controlled at the bottom dead center in the precompression step to compress the conductor 3, but the stopper It may be configured by an air cylinder or the like whose position can be regulated by another member such as, and may be compressed without controlling the bottom dead center if a predetermined compression ratio can be secured. Further, in the joining step, joining may be performed without controlling the bottom dead center.
Further, the horn driving unit 22 for moving the horn 12 and the ultrasonic vibration generating unit 21 for ultrasonically vibrating the horn 12 may be integrally configured.

In the above description, five coated electric wires 1 are joined to form a bonded electric wire 1a, but the number of the coated electric wires 1 is not limited, and an appropriate number of conductors 3 of the coated electric wires 1 are joined to form the bonded electric wire 1a. It may be configured.
Further, the wires constituting the conductor 3 in one covered electric wire 1 may be joined by the electric wire connecting device 10.

Further, in the above description, the conductor 3 made of aluminum alloy and the conductor 3 made of copper alloy are joined, but a conductor 3 of another metal type having conductivity such as a conductor 3 made of aluminum or a conductor 3 made of copper is used. You may use it. Further, it may be configured to join three or more kinds of metal conductors 3.

Further, as shown in FIG. 9, a compressive force having a pattern different from that described above may be applied to the bonded body to join the bonded body.
Specifically, in the above description, after moving to the bottom dead point at the time of compression by the second compressive force and precompressing, the force is once lowered to the third compressive force, and then the first compression is performed while applying ultrasonic vibration. The first bonding step of ultrasonically bonding to the bottom dead point at the time of bonding was performed by force, but as shown in FIG. 9A, after moving to the bottom dead point at the time of compression by the second compressive force and precompressing, You may perform the first bonding step of ultrasonically bonding to the bottom dead point at the time of bonding with the first compressive force while applying ultrasonic vibration without lowering to the third compressive force.

Further, in the above description, the second compressive force that moves to the bottom dead center during compression and precompresses is larger than the first compressive force that ultrasonically joins to the bottom dead center during joining while applying ultrasonic vibration. As shown in FIG. 9B, the compressive force that moves to the bottom dead center during compression and precompresses, and the compressive force that ultrasonically joins to the bottom dead center during joining while applying ultrasonic vibration. May be the same compressive force.

Even if the compressive force that moves to the bottom dead center during compression and precompresses is the same as the compressive force that ultrasonically bonds to the bottom dead center during bonding while applying ultrasonic vibration.
After pre-compressing, the compressive force may be reduced once, and then the first joining step may be performed.

1 ... Covered wire 2 ... Insulation coating 3 ... Conductor 4 ... Joint pipe 11 ... Anvil 12 ... Horn

Claims (6)

This is an electric wire connection method in which a plurality of coated electric wires whose conductors are covered with an insulating coating are arranged along the longitudinal direction, and the conductors of the plurality of coated electric wires arranged along the longitudinal direction are connected by an electric wire connecting device. hand,
A compression step of compressing a plurality of the conductors with a predetermined first compressive force so as to have a predetermined compression ratio, and
A bonding step is performed in which ultrasonic vibration is applied to the compressed conductor while applying a second compressive force smaller than the first compressive force to ultrasonically bond the plurality of conductors.
The plurality of conductors are a plurality of types of metal conductors having different compressive deformability due to a predetermined compressive force.
The predetermined compressibility for compressing the plurality of conductors in the compression step is
A wire connecting method in which a conductor of a metal type having the highest compressive deformability is compressed at a compressibility of 65% or more among the plurality of conductors. The predetermined compression ratio is
The electric wire connecting method according to claim 1, wherein the conductor of the metal type having the lowest compressive deformability is compressed at a compressibility of 90% or less among the plurality of conductors. In the compression step
While applying the first compressive force to the plurality of conductors arranged in the conductor arrangement portion of the electric wire connecting device, the compression vibrating portion that applies ultrasonic vibration of the electric wire connecting device is subjected to the predetermined compression ratio. Move to the compression relative position based on
In the joining process
The first joining step of joining the conductors by applying ultrasonic vibration while applying the second compressive force to the conductors until the compression vibrating portion is in a joint relative position with respect to the conductors.
After the compressive vibrating portion reaches the joint relative position, the conductor is joined by applying ultrasonic vibration while maintaining the joint relative position and lowering the compressive force acting on the conductor from the second compressive force. The electric wire connecting method according to claim 1 or 2, wherein the second joining step is performed. The electric wire according to claim 3, wherein the compressive force of the compression vibrating portion moved to the compression relative position in the compression step is reduced to a third compressive force smaller than the second compression force before the joining step. Connection method. One of the plurality of conductors is made of aluminum or an aluminum alloy, and
The other of the plurality of conductors is composed of copper or a copper alloy.
The electric wire connecting method according to any one of claims 1 to 4, wherein the metal type having high compressive deformability is aluminum or an aluminum alloy. A plurality of the conductors are inserted inside a conductive tubular body,
The electric wire connecting method according to any one of claims 1 to 5, wherein a plurality of the conductors together with the tubular body are compressed in the compression step and ultrasonically bonded in the joining step.

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