JP7233246B2 - Wire connection method - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electric wire connection method for joining conductors such as core wires and stranded wires in a plurality of covered electric wires constituting a wiring harness for an automobile.

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

As a method for connecting a plurality of covered electric wires constituting the above-described wire harness, for example, as described in Patent Document 1, the conductors of a plurality of covered electric wires are bundled together and ultrasonic vibration is applied to generate ultrasonic waves. A joining method is used. Specifically, the anvil (conductor placement part), which is a conductor receiving part that receives the conductor, bundles and arranges the conductors of multiple coated wires, and the horn (compression vibration part) that applies ultrasonic vibrations is attached to the anvil (conductor placement part). Part) is brought into contact with the bundled conductor and ultrasonically bonded.

Along with the recent diversification, it is common to join coated wires with different metal types of conductors, such as joining an aluminum covered wire having an aluminum alloy conductor and a copper covered wire having a copper alloy conductor. It is
Even if ultrasonic vibrations are applied to conductors of dissimilar metals to perform ultrasonic bonding, the conductors of different metals have different thermal conductivity, deformability, and melting temperature. was there.

Japanese Patent Application Laid-Open No. 2000-188018

The present invention provides a wire connection method capable of reliably joining conductors of different metal types by applying ultrasonic vibrations to the conductors of a plurality of coated wires arranged along the longitudinal direction, the conductors of which are covered with an insulating coating. intended to provide

The present invention is an electric wire in which a plurality of covered electric wires each having a conductor covered with an insulating coating are arranged along the longitudinal direction, and the conductors of the plural covered electric wires arranged along the longitudinal direction are connected by a wire connecting device. A connection method comprising: a compression step of compressing the plurality of conductors with a predetermined first compression force to a predetermined compression rate; and applying a second compression force smaller than the first compression force to the compressed conductors. and a bonding step of ultrasonically bonding a plurality of the conductors by applying ultrasonic vibration while acting, and the plurality of conductors are a plurality of types of metal conductors having different compressive deformation properties due to a predetermined compressive force. wherein the predetermined compression ratio for compressing the plurality of conductors in the compressing step is a compression ratio of 65% or more for a conductor of a metal type having the highest compressive deformability among the plurality of conductors. wherein one of the plurality of conductors is made of aluminum or an aluminum alloy, the other of the plurality of conductors is made of copper or a copper alloy, and the metal species having high compressive deformability is aluminum or aluminum It is characterized by being an alloy .

The conductor is, 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 strands of a single metal type, or a stranded wire in which strands of a plurality of metal types are mixed.

The compressibility mentioned above is the ratio of the cross-sectional area of the conductor after compressive deformation to the cross-sectional area of the conductor before being compressed.
Therefore, the compressibility of 65% or more mentioned above means that the cross-sectional area of the conductor before being compressed becomes 65% or more after compressive deformation.
The highest compressive deformability mentioned above 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 with different compressive deformability due to a predetermined compressive force, or may be three or more types of metal conductors. In addition, even if the metal species are different, if they have the same compressive deformability, they are considered to be of the same type in this specification.

According to this invention, the conductors of different metal types can be reliably joined.
Specifically, a compression step of compressing the plurality of conductors with a predetermined first compression force to a predetermined compression ratio, and applying a second compression force smaller than the first compression force to the compressed conductors. a bonding step of ultrasonically bonding a plurality of the conductors by applying ultrasonic vibrations while the compression force is being applied to bond the plurality of metal conductors having different compressive deformation properties due to a predetermined compression force. In order to set the predetermined compression rate for compressing the plurality of conductors in the process to a 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, A contact area between conductors can be ensured, and ultrasonic bonding can be performed reliably. In addition, since the contact area between the conductors can be secured, the conductors can be securely joined with a small thermal energy, that is, a small ultrasonic vibration energy.

Furthermore, when only the bonding process of ultrasonically bonding multiple types of conductors with different compressive deformability is performed without the compression process, the difference in deformation between the conductors with different compressive deformities in the bonding process increases, and the compressive deformability Only the conductors of the metal species with the highest compressive deformability are in an over-bonded state, but since the conductors of the metal species with the highest compressive deformability are compressed in advance in the compression process so that the compression rate is 65% or more, that is, the predetermined Since ultrasonic vibration is applied to conductors compressed at a compressibility of can be spliced.

Further, one of the plurality of conductors is made of aluminum or an aluminum alloy, the other of the plurality of conductors is made of copper or a copper alloy, and the metal species having high compressive deformability is made of aluminum or an aluminum alloy. Therefore, 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, a conductor made of aluminum or an aluminum alloy and a conductor made of copper or a copper alloy differ in hardness, thermal conductivity, and melting temperature, making it difficult to join. However, in the compression process, the aluminum or aluminum alloy conductor is compressed at a compression ratio of 65% or more as a conductor with high compressive deformation property, and then the joining process is performed, so the contact area between the conductors is secured. , can be reliably joined.

As an aspect of the present invention, the predetermined compressibility may be a compressibility of 90% or less for a conductor having the lowest compressive deformability among the plurality of conductors.
The lowest compressive deformability mentioned above refers to a conductor of a metal type that is least deformable by a predetermined compressive force among a plurality of conductors having different compressive deformability.
The compressibility of 90% or less mentioned above means that the cross-sectional area of the conductor before compression becomes 90% or less after compressive deformation.

According to the present invention, conductors having different compressive deformability can be joined more reliably and efficiently.
Specifically, in the compression step, the conductor of the metal species with the highest compressive deformability is compressed at a compression ratio of 65% or more, and the conductor of the metal species with the lowest compressive deformability is compressed at a compression ratio 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 compressing step, the compression vibrator for applying ultrasonic vibrations of the wire connection device to the plurality of conductors arranged in the conductor arrangement portion of the wire connection device is arranged in the predetermined It is moved to a compression relative position based on the compressibility, and in the bonding step, ultrasonic vibration is applied while the second compression force is applied to the conductor until the compression vibration part reaches the bonding relative position with respect to the conductor. a first joining step of applying and joining the conductor; and after the compressive vibrator reaches the joining relative position, maintaining the joining relative position and reducing the compressive force acting on the conductor from the second compressive force. A second bonding step of bonding the conductors by applying ultrasonic vibration while decreasing may be performed.

The above-described compression relative position and bonding relative position with respect to the conductors are positions at which the compression vibration section applies ultrasonic vibration to the plurality of conductors arranged in the conductor placement section of the wire connection device so that ultrasonic bonding can be performed. , position control to maintain the position of the compressed and ultrasonically bonded conductors, and control of changes in position as the conductors are compressed by the ultrasonic bonding.

According to the present invention, in the first joining step, the plurality of conductors compressed at the predetermined compression ratio are subjected to the second compressive force until the compression vibration portion comes to a joining relative position with respect to the conductors. is applied to the conductor to apply ultrasonic vibration to join the conductor, and in the second joining step, the compressive force acting on the conductor is applied to the conductor by the compression vibrator maintained at the joining relative position. 2. Since the conductors are joined by applying ultrasonic vibration while reducing the compressive force, the deformation of the conductors to be ultrasonically joined can be controlled, the influence of material variations 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 compressive vibration portion moved to the compressive relative position in the compressing step is reduced to a third compressive force smaller than the second compressive force before the joining step. may
According to the present invention, compressed conductors can be joined more reliably.

More specifically, before the joining step after the compression step of compressing the bundled conductors with a predetermined first compression force larger than the second compression force, the compression force of the compression vibrator acting on the conductors is Once it is lowered to a predetermined third compression force smaller than the second compression force, and then increased to the second compression force while applying ultrasonic vibration, the load acting on the compressed conductor is reduced while increasing the It can be joined securely.

Further, as an aspect of the present invention, a plurality of the conductors may be inserted into the 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 regulating the conductors by the tubular body. Moreover, since the conductor is regulated by the tubular body, it is possible to prevent the conductor to be joined from sticking to the compression vibrating portion or the conductor placement portion.

According to the present invention, there is provided a wire connection method capable of reliably joining conductors of different metal types by applying ultrasonic vibrations to a plurality of conductors arranged along the longitudinal direction, the conductors being coated with an insulating coating. can do.

Explanatory drawing about the covered electric wire which is a joining object. Schematic block diagram of a wire connection device. Flowchart of a wire connection method. Schematic explanatory drawing of the principal part of a wire connection apparatus. FIG. 4 is a schematic explanatory diagram of the joining operation of the main parts of the wire connecting device; Relation between Compressive Force and Relative Position of Horn to Conductor in Wire Connection Device The figure explaining the compressive deformation of the conductor in the joining process by the presence or absence of a pre-compression process. A table of the results of the demonstration experiment. 5 is a graph showing the relationship between the compressive force of the horn with respect to the conductor and the relative position in the wire connecting device of another embodiment;

One embodiment of the present invention will be described in detail below with reference to the drawings.
1A and 1B are explanatory diagrams related to a covered wire 1 to be joined. More specifically, FIG. 1A shows a plan view of a state in which a plurality of covered wires 1 to be joined are arranged in parallel, and FIG. FIG. 1(c) shows a plan view of a state in which conductors 3 of a plurality of insulated wires 1 arranged in parallel are bundled, and FIG. d) shows a plan view of a joint wire 1a formed by joining conductors 3 of a plurality of coated wires 1. FIG.

2 shows a schematic block diagram of the wire connecting device 10, and FIG. 3 shows a flow chart of the wire connecting method.
FIG. 4 shows a schematic explanatory view of the main part 10a of the wire connection device 10, and more specifically, FIG. Fig. 4(b) shows a schematic perspective view of a state in which conductors 3 of a plurality of coated wires 1 arranged in parallel are bundled and mounted inside a joint pipe 4, and Fig. 4(c) shows a wire connecting device. FIG. 4D shows a schematic perspective view of a state before a plurality of covered wires 1 are arranged with respect to the main portion 10a of the wire connection device 10, and FIG. 1 shows a schematic perspective view of the .

5A and 5B are schematic explanatory diagrams of the joining operation of the main part 10a of the wire connection device 10. Specifically, FIG. 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 to approach the anvil 11 constituting the main portion 10a of the wire connecting device 10, and FIG. ) shows a cross-sectional view of the state in which the horn 12 pre-compresses the plurality of conductors 3 with the first compression force, and FIG. Figure shows.

FIG. 6 is a graph showing the relationship between the compressive force and the relative position of the horn 12 with respect to the conductor 3 in the wire connecting device 10, and FIG. , and FIG. 8 is a table showing the results of the demonstration experiment.

In the wire connection method of the present invention described below, a plurality of covered wires 1 each having a conductor 3 covered with an insulating coating 2 are arranged along the longitudinal direction L, and the plurality of covered wires arranged along the longitudinal direction L are arranged. A joint pipe 4 is attached to one conductor 3, and ultrasonic vibration is applied while applying a second compressive force to join a plurality of conductors 3 to form a joint electric wire 1a joined by a conductor joint portion 3a. This is a method for this purpose, and is carried out using a wire connecting device 10, which will be described later.

The covered electric wire 1 to be joined is a covered electric wire composed of a conductor 3 which is a twisted wire obtained by twisting a plurality of wires twisted together, and an insulating coating 2 which covers the outside of the conductor 3 .
At least one conductor 3 among the plurality of covered wires 1 is a stranded wire made of aluminum alloy strands, and the conductors 3 of the other covered wires 1 are made of stranded wires made of copper alloy strands. there is In other words, the plurality of conductors 3 to be joined are joined with dissimilar metals.

In order to join a plurality of conductors 3 configured in this way, as shown in FIG. The covered electric wires 1 are arranged above between the covered electric wires 1, a total of five covered electric wires 1 are arranged, the conductors 3 are bundled together, and a joint pipe 4 is attached.

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

Then, in the wire connecting device 10 to be described later, ultrasonic vibration is applied to the bundled conductor 3 of the five coated wires 1 arranged as described above, and the conductor joint portion 3a is formed inside the joint pipe 4 by ultrasonic bonding. A joint electric wire 1a is formed by electrically and physically joining a plurality of covered electric wires 1 via conductor joint portions 3a.

As shown in FIG. 4C, a wire connecting device 10 that joins a plurality of conductors 3 to form a joint wire 1a includes an anvil 11 on which a plurality of conductors 3 are arranged, and a conductor 3 placed on the anvil 11. On the other hand, a horn 12 that applies ultrasonic vibrations to the conductors 3 and a restricting portion 13 that moves in the width direction W along the bottom surface of the horn 12 and restricts the width direction W of the plurality of conductors 3. and a main part 10a.

Further, as shown in FIG. 2, the wire connecting device 10 includes an ultrasonic vibration generator 21 for ultrasonically vibrating the horn 12 constituting the main part 10a, a horn driving part 22 for vertically moving the horn 12, and a regulation part. 13 in the width direction W, the ultrasonic vibration generator 21, the horn driver 22 and the jaw driver 23 are connected to each other. and a timer 25 connected to the controller 24 .

The wire connecting device 10 configured as described above controls the ON/OFF of the ultrasonic vibration of the horn 12 by controlling the control unit 24, moves the horn 12 up and down at a predetermined variable pressure, and controls the movement of the horn 12. At the bottom dead center of downward movement (in the conductor 3, the aluminum alloy conductor 3 with high compressive deformability has a compression rate of 65% or more, and the copper alloy conductor 3 with low compressive deformation is compressed at a compression rate of 90% or less. It is possible to stop the movement at the bottom dead center during compression or the bottom dead center during joining, that is, the bottom dead center control can be performed.

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

Further, the control section 24 is connected to a clock section 25, and controls the driving of the ultrasonic vibration generating section 21, the horn driving section 22, and the jaw driving section 23 according to the time clocked by the clock section 25. can be done.

Next, a wire connection method for the covered wire 1 using the wire connection device 10 will be described below with reference to the flowchart shown in FIG. In this embodiment, a case where five coated wires 1 having aluminum alloy conductors 3 and five coated wires 1 having copper alloy conductors 3 are joined will be described with reference to FIGS. 4 to 6. FIG.

In addition, in FIG. 5, the positions of the horn 12 and the restricting portion 13 in the previous process are indicated by dashed lines. 6 is a graph showing the relationship between the compressive force of the horn 12 against the conductor 3 in each step described later and the height of the horn 12 moving downward in the wire connecting device 10. In the graph of FIG. A thick line indicates the part where the ultrasonic vibration is applied.

The insulating coating 2 at the tip of the covered wire 1 is stripped to expose the conductor 3 for a predetermined length, and the conductors 3 of the covered wire 1 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 each having joint pipes 4 attached to bundled conductors 3 are arranged on the upper surface of anvil 11 (step s2).
Then, as shown in FIG. 5B , the restricting 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 restricting portion 13 so as to approach the anvil 11 .

Further, as shown in FIG. 5( c ), the restricting portion 13 is moved inward in the width direction W along the bottom surface of the horn 12 until the inner side surface in the width direction W of the restricting portion 13 abuts the side surface of the anvil 11 . In addition to moving, the controller 24 controls to operate the horn drive unit 22 until the conductor 3 to which the joint pipe 4 is attached is compressed with a first compression force higher than a second compression force described later. At the same time, the horn 12 is moved downward (step s3: pre-compression step).

The pre-compression step (step s3) of the conductor 3 by the horn 12 is continued until the horn 12 moves to the bottom dead center during compression with respect to the conductor 3 placed on the anvil 11 (step s4: No).

Among the conductors 3 to which the joint pipe 4 is attached, the aluminum alloy conductor with high compressive deformation property has a compressibility of 65% or more, and the copper alloy conductor with low compressive deformation property has a compression ratio of 90% or less. When the downward movement of the horn 12 reaches the bottom dead center of the compression at which the compression ratio is equal to (step s4: Yes), the control unit 24 controls the horn driving unit 22 to increase the compression force of the horn 12 to a second compression force described later. Decrease to a third compression force lower than the compression force (see FIG. 6). As shown in FIG. 6, the horn 12 whose compressive force (first compressive force) is reduced to the third compressive force once rises from the bottom dead center during compression as the compressive force is reduced.

In other words, the horn 12 in which the compressive force to the conductor 3 placed on 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 s5), ultrasonic bonding is performed while compressing the conductor 3 with a second compression force lower than the first compression force and higher than the third compression force (step s6: first bonding step).

In this way, as shown in FIG. 5(d), in compression welding in which the conductor 3 is ultrasonically welded while being compressed with a second compression force lower than the first compression force and higher than the third compression force, the horn 12 is It continues until it moves to the bottom dead center at the time of joining which is a predetermined position with respect to the conductor 3 arranged on the anvil 11 (step s7: No).

When the downward movement of the horn 12 reaches the joining bottom dead center (step s7: Yes), the control section 24 controls the horn drive section 22 to stop the downward movement of the horn 12, and the timing section 25 starts timing. 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 compression force by the ultrasonically vibrating horn 12 at the bottom dead center during bonding. The conductors 3 are ultrasonically bonded while being pressed (second bonding step).

When the horn 12, which is ultrasonically vibrated at the bottom dead center during bonding, has applied the second compressive force for a predetermined time (step s8: Yes), the conductors 3 are ultrasonically bonded to each other inside the joint pipe 4 to form a conductor. A joint portion 3a (see FIG. 1(d)) can be configured. In this manner, a bonded electric wire 1a can be formed by connecting a plurality of covered electric wires 1 via a conductor joint portion 3a in which the conductors 3 are ultrasonically welded to each other.

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

Specifically, a pre-compression step (step s3) of compressing the plurality of conductors 3 with a predetermined first compression force to a predetermined compression rate, and applying a second compression force smaller than the first compression force to the compressed conductors 3 (step s3). A bonding step (steps s6 to s8) of ultrasonically bonding 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 deformation properties due to a predetermined compressive force are performed. In order to join the conductors 3, a predetermined compression ratio for compressing the plurality of conductors 3 in the pre-compression step (step s3) is set to 65 % or more, the contact area between the conductors 3 can be ensured, and the ultrasonic bonding can be reliably performed. Moreover, since the contact area between the conductors 3 can be ensured, the conductors 3 can be joined with a small thermal energy, that is, a small ultrasonic vibration energy.

Furthermore, as shown in FIG. 7, only a bonding step (step s6 to s8), the difference in deformation increases between the conductors 3 with different compressive deformability in the joining process (steps s6 to s8), and only the aluminum alloy conductor 3 with high compressive deformability is over-joined. .

On the other hand, since the conductor 3 made of aluminum alloy with high compressive deformability is compressed in advance in the pre-compression step (step s3) so that the compression rate is 65% or more, that is, the predetermined compression rate (aluminum In order to perform ultrasonic bonding by applying ultrasonic vibration to the conductor 3 compressed at a compression ratio of 65% or more, the conductor 3 having different compressive deformability in the bonding process (steps s6 to s8) The difference in deformation between them can be reduced, and even between the conductors 3 having different compression deformability, ultrasonic bonding can be performed.

Further, in the pre-compression step, among the plurality of conductors 3, the conductor 3 made of a copper alloy with low compressive deformation is set to a compression rate of 90% or less, so that the conductors 3 having different compressive deformation properties can be joined more reliably and efficiently.

Specifically, in the pre-compression step (step s3), the aluminum alloy conductor 3 with high compressive deformability is compressed at a compression ratio of 65% or more, and the copper alloy conductor 3 with low compressive deformability is reduced to 90%. % or less, all the conductors 3 with 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. can.

In addition, here, the result of the demonstration experiment of the compression rate in the above-mentioned pre-compression process (step s3) is demonstrated based on FIG.
As a demonstration experiment, the conductors of three 2.0 sq copper alloy covered wires and the conductors of three 2.0 sq aluminum alloy covered wires were compressed at a predetermined compression ratio and then subjected to a predetermined pressure. After ultrasonic bonding, the resistance value after ultrasonic bonding was measured. The evaluation results are shown in Table 8 as "O" when the resistance value between the wires is 0.5 mΩ or less, and as "X" when the resistance value between the wires is greater than 0.5 mΩ. In addition, in Table 8, the upper side indicates the case of strong compression (when the compressibility value is low), and the right side indicates the case of high pressure during ultrasonic bonding.

As can be seen from Table 8, it is confirmed that the aluminum alloy conductor 3 has a large resistance value between wires when the pressure is high or the compression ratio is 60%, and the copper alloy conductor 3 , it was confirmed that the resistance value between the wires increases when the applied pressure is low or when the compression rate is 100%, that is, when there is no compression.
On the other hand, when the compressibility is 65% or more and 90% or less, it has been confirmed that the resistance value between wires of both the aluminum alloy conductor 3 and the copper-gold conductor 3 is reduced in many cases.

From this, when the compressibility is lower than 65% (lower compressibility value), the aluminum alloy conductor, which has higher compressive deformation than the copper alloy conductor, tends to become defective, and the compressibility is 90%. As the compression rate becomes higher (higher compressibility value), the copper alloy conductor, which has lower compression deformation than the aluminum alloy conductor, tends to become defective, and is pre-compressed at a compression rate of 65% or more and 90% or less. Thus, 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 compresses the plurality of conductors 3 received by the anvil 11 while applying ultrasonic vibrations to a predetermined compression rate while applying a first compression force. The horn 12 is placed on the anvil 11 to apply ultrasonic vibration to the wire connecting device 10 in the joining step (steps s6 to s8), and is moved to the bottom dead center (the position where the compression ratio described above) is obtained. A first joining step (step s6 to s7), after the horn 12 reaches the bonding bottom dead center, the ultrasonic vibration is applied while maintaining the bonding bottom dead center and reducing the compressive force acting on the plurality of conductors 3 from the second compressive force. By performing the second bonding step (step s8) for bonding a plurality of conductors 3 by applying the can improve the robustness of

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

Specifically, before the joining process (steps s6 to s8) after the pre-compression process (step s3) for compressing the bundled conductors 3 with a predetermined first compression force larger than the second compression force, the conductor 3 is The compressive force of the horn 12 that causes the compression force 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, so that the compressed conductor 3 More reliable joining can be achieved while reducing the acting load.

Further, 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 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, thermal conductivity, and melting temperature. It is difficult to join. On the other hand, in the pre-compression step (step s3), the aluminum alloy conductor 3 is compressed at a compression ratio of 65% or more as a conductor 3 with high compressive deformation, and then the bonding step (steps s6 to s8) is performed. Therefore, the contact area between the conductors 3 can be ensured and the conductors 3 can be reliably joined.

In addition, the 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 pre-compression step (step s3), and are super-stretched in the joining step (steps s6 to s8). Since sonic bonding is used, the conductors 3 of different metal types can be reliably bonded while the conductors 3 are regulated by the joint pipe 4 . Moreover, since the conductor 3 is regulated by the joint pipe 4 , the conductor 3 to be joined can be prevented from sticking to the horn 12 and the anvil 11 .

In correspondence with the configuration of this invention and the above-described embodiments,
In the connection device of the present invention, the conductor in the above embodiment corresponds to the conductor 3, and so on.
The insulation coating corresponds to insulation coating 2,
The covered wire corresponds to covered wire 1,
The compression step corresponds to the pre-compression step (step s3),
The bonding process corresponds to the bonding process (steps s6 to s8),
The metal type conductor with the highest compressive deformability corresponds to the aluminum alloy conductor 3,
The metal type conductor with the lowest compressive deformability corresponds to the copper alloy conductor 3,
The conductor arrangement part corresponds to the anvil 11,
The compression vibration part corresponds to the horn 12,
The joint relative position corresponds to the bottom dead center at the time of joint,
The compression relative position corresponds to the bottom dead center during compression,
The wire connection device corresponds to the wire connection device 10,
Although the tubular body corresponds to the joint pipe 4,
The present invention is not limited only to the configurations of the above-described embodiments, but 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 with a position controllable drive system capable of moving the horn 12 to a predetermined position, and the conductor 3 is compressed by controlling the bottom dead center of the horn 12 in the pre-compression process, but the stopper If a predetermined compression rate can be ensured, compression may be performed without bottom dead center control. Also, in the joining step, joining may be performed without bottom dead center control.
Further, the horn driving section 22 for moving the horn 12 and the ultrasonic vibration generating section 21 for ultrasonically vibrating the horn 12 may be integrated.

In the above description, five covered electric wires 1 are joined to constitute the joined electric wire 1a, but the number of the covered electric wires 1 is not limited, and an appropriate number of the conductors 3 of the covered electric wires 1 are joined to form the joined electric wire 1a. may be configured.
Alternatively, the wire connecting device 10 may be used to join the strands of the conductor 3 in one covered wire 1 to each other.

Furthermore, in the above description, the conductor 3 made of aluminum alloy and the conductor 3 made of copper alloy are joined together, but the conductor 3 made of another conductive metal such as the conductor 3 made of aluminum or the conductor 3 made of copper may be used. may be used. Furthermore, it may be configured to join three or more types of metal conductors 3 .

Alternatively, as shown in FIG. 9, the objects to be joined may be joined by applying a different pattern of compressive force to the objects to be joined.
Specifically, in the above description, after moving to the bottom dead center at the time of compression with the second compression force and pre-compressing, once decreasing to the third compression force, the first compression is performed while ultrasonic vibration is applied. Although the first bonding step of ultrasonically bonding to the bottom dead center at the time of bonding with force was performed, as shown in FIG. A first bonding step may be performed in which the first compression force is ultrasonically bonded to the bottom dead center at the time of bonding while applying ultrasonic vibration without reducing the compression force to the third compression force.

Furthermore, in the above description, the second compression force that moves to the bottom dead center during compression and pre-compresses is greater than the first compression force that ultrasonically bonds to the bottom dead center during bonding while applying ultrasonic vibration. As shown in FIG. 9B, the compression force that moves to the bottom dead center during compression and pre-compresses, and the compression force that ultrasonically welds to the bottom dead center during bonding while applying ultrasonic vibration. may be the same compressive force.

Even if the compressive force for pre-compressing by moving to the bottom dead center during compression and the compressive force for ultrasonically bonding to the bottom dead center during bonding while applying ultrasonic vibration are the same compressive force,
After pre-compressing, the first bonding step may be performed after the compressive force is once reduced.

DESCRIPTION OF SYMBOLS 1... Coated electric wire 2... Insulating coating 3... Conductor 4... Joint tube 11... Anvil 12... Horn

Claims (5)

A wire connection method for arranging a plurality of covered wires each having a conductor covered with an insulating coating along a longitudinal direction, and connecting the conductors of the plurality of covered wires arranged along the longitudinal direction with a wire connecting device. hand,
a compression step of compressing the plurality of conductors with a predetermined first compression force to a predetermined compression ratio;
a bonding step of applying ultrasonic vibrations to the compressed conductors while applying a second compression force smaller than the first compression force to ultrasonically bond a plurality of the conductors;
The plurality of conductors are conductors made of a plurality of types of metals having different compressive deformation properties due to a predetermined compressive force,
The predetermined compression ratio for compressing the plurality of conductors in the compressing step is
Among the plurality of conductors, a compression rate at which a conductor of a metal type having the highest compressive deformability is compressed at a compression rate of 65% or more,
one of the plurality of conductors is made of aluminum or an aluminum alloy,
The other of the plurality of conductors is made of copper or a copper alloy,
The metal species having high compressive deformability is aluminum or an aluminum alloy
Wire connection method. The predetermined compression ratio is
2. The electric wire connection method according to claim 1, wherein, among the plurality of conductors, a conductor of a metal having the lowest compressive deformability has a compressibility of 90% or less. In the compression step,
While applying the first compressive force to the plurality of conductors arranged in the conductor placement portion of the wire connection device, the compression vibration unit that applies ultrasonic vibration of the wire connection device to the predetermined compression rate. to the compression relative position based on
In the bonding step,
a first joining step of joining the conductor by applying ultrasonic vibration while applying the second compressive force to the conductor until the compressive vibration part reaches a joint relative position with respect to the conductor;
After the compressive vibrator reaches the bonding relative position, the bonding relative position is maintained, and ultrasonic vibration is applied while reducing the compressive force acting on the conductor from the second compressive force to bond the conductor. 3. The wire connection method according to claim 1 or 2, wherein a second joining step is performed. 4. The electric wire according to claim 3, wherein the compressive force of said compressive vibrator moved to said compression relative position in said compressing step is reduced to a third compressive force smaller than said second compressive force before said joining step. connection method. inserting a plurality of said conductors inside a conductive tubular body;
5. The electric wire connection method according to claim 1, wherein the plurality of conductors are compressed together with the tubular body in the compressing step and ultrasonically joined in the joining step.

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