DE102020204956A1 - Ultrasonic joining method - Google Patents

Abstract

An ultrasonic joining method comprising: holding a workpiece (a conductor 21) containing aluminum or an aluminum alloy by a holding surface (P) of each of a horn (61) and an anvil (62); and applying an ultrasonic wave from the horn (61) to perform ultrasonic bonding processing on the workpiece (the conductor 21) in which a releasing member (H) containing copper or a copper component is sandwiched between at least a part of the workpiece (the conductor 21) made of aluminum or an aluminum alloy, and the holding surface (P) when the workpiece (the conductor 21) is held by the holding surface (P) is arranged.

Description

[Technical area]

The present invention relates to an ultrasonic joining method.

[Description of the Prior Art]

There is known an ultrasonic welding method in which, when a connection base material obtained by stacking an aluminum sheet and a steel sheet is welded with an ultrasonic wave, a carbonaceous sheet is stacked on the connection base material and between a chip and the connection base material and / or is placed between an anvil and the connection base material (see, for example, Patent Literature 1). According to this method, severe deformation and adhesion (sticking) of a surface layer portion of a joint portion after ultrasonic welding can be prevented.

A technique has been described that allows an elastic body made of a heavy metal to adhere to a slider material by stacking the elastic body on a piezoelectric body that generates a propagating wave (im English "traveling wave") generated to form a vibrating body by preparing the sliding material formed of a heat-resistant resin composition made by adding a metal deactivator to a heat-resistant resin, and bringing a moving body into pressure contact with the vibrating body can be prevented by means of the sliding material (see, for example, Patent Literature 2).

[Prior art documents]

[Patent documents]

• Patent Literature 1: Japanese Patent No. 4180405
• Patent literature 2: Japanese Patent No. 3229379

[Summary of the invention]

[Problem to be solved by the invention]

However, both the sheet metal described above and the sliding material described above are expensive, so that the manufacturing costs increase. In a case where a portion to be processed is a conductive portion, the sheet metal or the sliding material may adhere to the portion to be processed which is the conductive portion, which may deteriorate conductivity or the like and lead to deterioration in quality.

It has also been investigated to attach a powder of boron nitride or the like to a horn or an anvil, or to coat a horn or an anvil with diamond-like carbon or the like. However, when an ultrasonic wave is applied, powder of boron nitride or the like is scattered, and a coating of diamond-like carbon or the like is cracked. In either case, the cost is increased.

The present invention has been made in view of the above-described circumstances. One aspect of the present invention provides an ultrasonic bonding method that can improve productivity by preventing a workpiece from sticking to a horn or an anvil at a low cost and by performing stable, high-quality processing.

[Means of solving the problem]

• (1) Ultraschallbindungsverfahren, umfassend:
  • Halten eines Werkstücks, das Aluminium oder eine Aluminiumlegierung enthält, durch eine Haltefläche von jeweils einem Horn und einem Amboss; und Anlegen einer Ultraschallwelle vom Horn, um eine Ultraschallverbindungsverarbeitung an dem Werkstück durchzuführen, wobei ein Freigabeelement, das Kupfer oder eine Kupferkomponente enthält, zumindest zwischen einem Teil des Werkstücks, das aus Aluminium oder einer Aluminiumlegierung besteht, und der Haltefläche angeordnet ist, wenn das Werkstück von der Haltefläche gehalten wird.
• (2) Ultraschallverbindungsverfahren nach obiger (1), wobei das Freigabeelement eine Kupferfolie oder eine Metallfolie, die eine Kupferkomponente enthält, ist.
• (3) Ultraschallverbindungsverfahren nach obiger (1), wobei das Freigabeelement ein Kupferpulver oder ein Metallpulver, das eine Kupferkomponente enthält, ist.

In order to achieve the above-described aspect, there is provided an ultrasonic joining method according to the present invention, which is characterized by the following items (1) to (3).

• (1) Ultrasonic bonding process, including:
  • Holding a workpiece containing aluminum or an aluminum alloy by a holding surface each of a horn and an anvil; and applying an ultrasonic wave from the horn to perform ultrasonic bonding processing on the workpiece, wherein a releasing member containing copper or a copper component is disposed at least between a part of the workpiece made of aluminum or an aluminum alloy and the holding surface when the workpiece is held by the holding surface.
• (2) The ultrasonic joining method according to (1) above, wherein the releasing member is a copper foil or a metal foil containing a copper component.
• (3) The ultrasonic joining method according to (1) above, wherein the releasing member is a copper powder or a metal powder containing a copper component.

According to the ultrasonic bonding method or ultrasonic bonding method with one configuration According to item (1), the releasing member containing copper or a copper component is disposed at least between the part of the workpiece formed of aluminum or an aluminum alloy and the holding surface when the workpiece is held by the holding surface. Accordingly, it is possible to prevent adhesion between the workpiece and the holding surface after the ultrasonic bonding processing, whereby a releasing operation (peeling process) after the ultrasonic bonding processing can be eliminated and thus productivity can be improved. The method is particularly suitable for machining a workpiece made of high-strength aluminum that requires high ultrasonic energy.

The release member or release member containing copper or a copper component is used to prevent adhesion to the holding surface, so that it is possible to perform high quality and stable processing at low cost. The releasing process (peeling process) is omitted, so it is possible to continuously perform the ultrasonic bonding processing and improve the production efficiency. In addition, during the ultrasonic joining processing, it is possible to apply a large ultrasonic energy or load and ultrasonic joining the workpiece with high strength.

According to the ultrasonic bonding method having a configuration of item (2), a copper foil or a metal foil containing a copper component is used as the releasing member, and therefore it is possible to easily arrange the releasing member between the workpiece and the holding surface and further improve the workability . When the releasing member is formed from a copper foil or a metal foil containing a copper component, the releasing member is in face contact with the workpiece and the holding surface in a wide area, so that it is possible to transmit ultrasonic energy well from the horn. Therefore, even if the workpiece is a conductor obtained by bundling strands such as the electric wires which are difficult to transmit the ultrasonic energy from the horn, it is possible to transmit the ultrasonic energy to the workpiece well through the releasing member to perform connection processing.

According to the ultrasonic joining method having a configuration of item (3), a copper powder or a metal powder containing a copper component is used as the releasing member, therefore it is possible to easily attach or interpose the releasing member to the workpiece or the holding surface.

[Advantages of the invention]

According to the present invention, it is possible to provide an ultrasonic joining method which can improve productivity by preventing a workpiece from sticking to a horn or an anvil at a low cost and processing can be performed stably and with high quality.

The present invention has been briefly described above. Details of the present invention will be further explained by describing a mode (hereinafter referred to as “embodiment”) for carrying out the present invention described below with reference to the accompanying figures.

Figure list

• 1 13 is a perspective view of an electric wire connected to a terminal that has been subjected to ultrasonic connection processing by an ultrasonic connection method according to an embodiment.
• 2 Fig. 13 is a schematic perspective view of an ultrasonic joining device configured to perform ultrasonic joining processing by the ultrasonic joining method according to the present embodiment.
• 3 Fig. 13 is a schematic plan view of the ultrasonic joining device configured to perform the ultrasonic joining processing by the ultrasonic joining method according to the present embodiment.
• 4A to 4C are schematic side views illustrating steps of the ultrasonic joining method according to the present embodiment.
• 5A and 5B show the tensile strength and the release strength of conductors connected by different ultrasonic energy. 5A FIG. 5 is a diagram showing a measurement result when a release element is used, and FIG. 5B is a diagram showing a measurement result when no release element is used.

[Methods for Carrying Out the Present Invention]

A specific embodiment according to the present invention will be described with reference to the figures.

First, an electric wire provided with a terminal that has been subjected to ultrasonic connection processing by an ultrasonic connection method according to the present embodiment will be described.

1 Fig. 13 is a perspective view of the electric wire attached to the terminal that has been subjected to the ultrasonic connection processing by the ultrasonic connection method according to the present embodiment.

As in 1 illustrated comprises the electrical cable attached to the terminal 10 an electrical cable 11 , a connection terminal 12 holding one end of the electrical cable 11 connected, and another electrical wire 13 that connects to the other end of the electrical cable 11 connected to. The electrical cables shown 11 , 13 are insulated wires with a conductor 21st and a shell 22nd having a scope of the head 21st covers. The head 21st is, for example, a stranded wire obtained by twisting strands of aluminum or an aluminum alloy. The case 22nd consists of a flexible and insulating resin material. At the end sections of the electrical wires 11 , 13 is the shell 22nd removed and part of the head 21st is exposed.

The head 21st the other electrical cable 13 that is at the end portion of the other electrical cable 13 is exposed, and the head 21st of the electrical cable attached to the end portion of the electrical cable 11 opposite to a connection side with the connection terminal 12 is exposed are connected and integrated with each other by the ultrasonic connection processing.

The connection terminal 12 is formed, for example, by processing a plate member formed from a conductive metal material such as copper, copper alloy, aluminum, aluminum alloy, or the like. The connection terminal 12 has an electrical cable connecting portion 31 and an electrical connection section 32 on.

The electrical cable connection section 31 is crimped (in English "crimped") and to part of the conductor 21st and the shell 22nd of the electrical cable 11 attached. The connection terminals are accordingly 12 and the electric cable 11 connected, and the connector 12 and the head 21st of the electrical cable 11 are electrically connected. The electrical connection section 32 is formed in a rectangular pipe shape, and a pin-shaped tab (not shown) formed on a connector terminal of a connection partner is inserted from a distal end side of the electrical connection portion (or terminal portion) 32. The connection terminal 12 is electrically connected to the connector by pulling the tab of the connector from a front side thereof into the electrical connection section 32 is introduced.

When the head 21st from each of the electrical cables 11 , 13 formed of aluminum or an aluminum alloy is subjected to ultrasonic joining processing, the conductor may 21st cling to a horn and an anvil that make up the ladder 21st hold between them. Then, after the ultrasonic connection processing, a releasing (or releasing) operation for releasing the conductor is performed 21st from the horn or anvil on which the conductor is attached 21st adheres, necessary, which can lead to a decrease in productivity. The head 21st is detached from the horn or anvil, leaving the tied head 21st separated and deformed, which can lead to deterioration in quality.

In the ultrasonic joining method according to the present embodiment, productivity and quality are improved by eliminating a need for the releasing operation. The ultrasonic joining method according to the present embodiment will be described below.

2 Fig. 13 is a schematic perspective view of an ultrasonic joining device configured to perform ultrasonic joining processing by the ultrasonic joining method according to the present embodiment. 3 Fig. 13 is a schematic plan view of the ultrasonic joining device configured to perform the ultrasonic joining processing by the ultrasonic joining method according to the present embodiment. 4A to 4C are schematic side views illustrating steps in the ultrasonic bonding method according to the present embodiment.

As in the 2 and 3 illustrated comprises an ultrasonic connector 60 according to the present embodiment, a horn 61 and an anvil 62 on. The Horn 61 has a vibration excitation element or vibrator (not shown), which causes an ultrasonic vibration by supplying an alternating current and is set in vibration by the vibration excitation element. The Horn 61 and the anvil 62 have facing holding surfaces P on. In the ultrasonic connection device 60 is the head 21st each of the electrical cables 11 , 13 , which is a workpiece, on a Ultrasonic connection position between the holding surfaces P of the horn 61 and the anvil 62 arranged. Then the ultrasonic vibration is from the horn 61 transmitted by the vibration excitation element in a state in which the conductor 21st by a load from the anvil 62 between the holding surfaces P of the horn 61 and the anvil 62 is held so that the ladder 21st be connected to each other with ultrasound.

The ultrasonic connection device 60 has a release element supply unit 65 on. The release element supply unit 65 indicates a transport route 66 and sends a release element H out of the transport route 66 to the ultrasonic connection position. That through the release element supply unit 65 sent approval element H is a copper foil or a metal foil containing a copper component, and is in a tape shape having substantially the same width dimension as that of the holding surfaces P of the horn 61 and the anvil 62 educated.

To the ultrasonic connection processing by the ultrasonic connection device 60 is carried out first as in 4A shown is part of the envelope 22nd to be subjected to connection processing at the end portions of the electric cables 11 , 13 away to the head 21st to expose.

Next, as in 4B shown is the ladder 21st attached to the end sections of electrical cables 11 , 13 are exposed, arranged to face each other at the ultrasonic connection position between the horn 61 and the anvil 62 the ultrasonic connecting device 60 overlap. At this point the release items H from the release element supply unit 65 sent to the ultrasonic connection position and between the conductor 21st which is the workpiece and the holding surface P of the horn 61 and between the conductor 21st and the holding surface P of the anvil 62 arranged. The release elements H are by a milling cutter (not shown) attached to the release element supply unit 65 is provided to be cut to a size to substantially cover the entire surface of the horn 61 and the anvil 62 to cover.

After the release element H is arranged, leads the ultrasonic connection device 60 the ultrasonic link processing on the conductor 21st at the end portions of the electrical cables 11 , 13 by. More specifically, an alternating current is applied to the vibration exciting element in a state in which the anvil 62 is lowered and the overlapping ladder 21st via the release element H through the holding surfaces P of the horn 61 and the anvil 62 the ultrasonic connecting device 60 be held with a predetermined load. Then the horn 61 set into ultrasonic oscillation or vibrated by the oscillation excitation element, so that ultrasonic oscillation energy is applied to the overlapping conductor 21st spreads. Then, oxide films or the like on surfaces of the strands are broken, removed and connected to each other, and the conductors 21st of electrical cables 11 , 13 are connected to each other with ultrasound.

After that, the anvil 62 and raised the ladder 21st of electrical cables 11 , 13 that have been ultrasonically bonded will move out of the ultrasonic bond position between the holding surfaces P of the horn 61 and the anvil 62 taken out. Here was the release item H between the holding surfaces P of the horn 61 and the anvil 62 and the ladders 21st when the ultrasonic connection processing is performed, so that the conductors made of aluminum or an aluminum alloy are prevented from being 21st on the holding surfaces P of the horn 61 and the anvil 62 cling. Hence it is possible to use the ladder 21st problem-free and easy from the ultrasonic connection position between the holding surfaces P of the horn 61 and the anvil 62 take out.

As described above, in the ultrasonic joining method according to the present embodiment, when the conductors 21st , which are the workpiece, through the holding surfaces P are the release elements H containing copper or a copper component between the conductors 21st and the holding surfaces P arranged. Accordingly, it is possible to reduce the adhesion between the conductors 21st and the holding surfaces P after the ultrasonic joint processing and to eliminate the releasing operation after the ultrasonic joint processing to improve productivity. The method is particularly suitable for machining a workpiece made of high-strength aluminum that requires high ultrasonic energy.

The release element H containing copper or a copper component is used to prevent adherence to the holding surfaces P to prevent, so that it is possible to perform high quality and stable processing at a low cost. The releasing process is omitted, so it is possible to continuously perform the ultrasonic connection processing and improve the production efficiency. In addition, during the ultrasonic joint processing, it is possible to apply a large ultrasonic energy or load and the workpiece being the conductor 21st or the like is to be combined with ultrasound with high strength.

In particular, when a copper foil or a metal foil containing a copper component is used as the releasing element H is used, it is possible to easily remove the release element H between the workpiece that the conductor 21st or the like, and the holding surface P and to further improve the processability. The release element formed from a copper foil or a metal foil containing a copper component H is in surface contact with the workpiece and the holding surface in a wide area P so that it is possible to get ultrasonic energy well from the horn 61 transferred to. Therefore, even if the workpiece is the conductor 21st that is obtained by bundling strands like the electric cables, which are difficult to get the ultrasonic energy from the horn 61 to transmit, possible, the ultrasonic energy via the release element H to transfer well to the workpiece to perform the connection processing.

In the embodiment described above, a copper foil or a metal foil containing a copper component is used as the releasing member H used. However, a copper powder or a metal powder containing a copper component can be used as the releasing element H be used. When a copper powder or a metal powder containing a copper component as the releasing element H is used, the release element H on the holding surfaces P of the horn 61 and the anvil 62 is applied when the ultrasonic connection processing is performed. The releasing member formed from a copper powder or a metal powder containing a copper component H is applied so that it is possible to reduce the adhesion between the holding surfaces due to the ultrasonic joint processing P of the horn 61 and the anvil 62 and the ladders 21st and to eliminate the release process after ultrasonic connection processing. Around the releasing member formed from a copper powder or a metal powder containing a copper component H on the holding surfaces P to apply, the release element H directly on the holding surfaces P of the horn 61 and the anvil 62 be sprayed on or a cloth bag that holds the release element H contains, can against the holding surfaces P be pressed. A solid element made by solidifying the release element H formed from a copper powder or a metal powder containing a copper component can be applied to the holding surfaces P rubbed and applied. A powdery carbonate (calcium carbonate, sodium carbonate, magnesium carbonate or the like) can be used together with the release element H on the holding surfaces P be attached.

Here, the tensile strength in an axial direction and the releasing strength or peeling strength in a connecting direction were used for the conductor 21st connected by the ultrasonic connection processing was measured. The release element H consists of a copper powder. 5A and 5B show the tensile strength and the release strength of conductors connected by different ultrasonic energies. 5A FIG. 13 is a diagram showing a measurement result when a release member is used, and FIG 5B Fig. 13 is a diagram showing a measurement result when no release member is used.

As in 5A is shown in the ultrasonic joining method in which the releasing member H on the holding surfaces P of the horn 61 and the anvil 62 is applied, when the ultrasonic connection processing is performed, even if the ultrasonic vibration energy is increased, it is possible to use the conductors 21st connect well and the tensile strength and release strength of the interconnected conductors 21st sufficient to achieve.

On the other hand, as in 5B is shown when the ultrasonic connection processing without using the releasing member H the conductors are connected 21st after the ultrasonic vibration energy 80 (AU) which is greater than 60 (AU) is, has reached, on the holding surfaces P of the horn 61 or the anvil 62 stuck, resulting in a bad connection.

It is accordingly when the release element is used H possible to have a good connection with the ultrasonic vibration energy of 60 (AU) to 100 (AU) as a condition for the ultrasonic bonding processing.

The present invention is not limited to the above-described embodiment, and can be modified, improved, or the like as appropriate. In addition, the material, shape, size, number, arrangement position, or the like of each component in the above-described embodiment are optional and not restrictive as long as the present invention can be achieved.

In the embodiment described above, a case is described where both electric cables 11 , 13 the head 21st made of aluminum or an aluminum alloy. However, the present invention can also be applied to a case where at least one of the two electric cables to be connected to each other 11 , 13 the conductor made of aluminum or an aluminum alloy 21st having. For example, if the head 21st of the one electrical cable 11 is formed from aluminum or an aluminum alloy and the head 21st the other electrical cable 13 is formed from copper or a copper alloy is the release element H at least between the conductor 21st made of aluminum or an aluminum alloy in the electric cable 11 and the holding surface P that the head 21st made of aluminum or an aluminum alloy facing, arranged.

In the embodiment described above, a case where the ladder 21st of electrical cables 11 , 13 are connected to each other by the ultrasonic connection processing. However, the ultrasonic bonding processing is not limited to being applied to the conductors 21st of electrical cables 11 , 13 connect to. For example, the present invention can also be applied to a case where the strands of the conductor 21st of the electrical cable 11 made of aluminum or an aluminum alloy are joined together by the ultrasonic joining processing. The present invention can also be applied to a case where a connection terminal made of a conductive metal material that is copper, a copper alloy, aluminum, an aluminum alloy, or the like is connected to the conductor 21st of the electrical cable 11 is connected to ultrasound formed from aluminum or an aluminum alloy through the ultrasonic connection processing.

In the embodiment described above, a case is described by way of example in which the release member formed from a metal foil H through the release element supply unit 65 is sent or transported to the ultrasonic connection position. The release element H However, formed from a metal foil cut into an appropriate size, can be prepared in advance, and an operator can control the releasing member H between the conductor 21st and the holding surface P insert and place between them.

Properties of the above-described ultrasonic joining method according to the embodiment of the present invention are briefly summarized under items [1] to [3], respectively:

• Halten eines Werkstücks (eines Leiters 21), das Aluminium oder eine Aluminiumlegierung enthält, durch eine Haltefläche (P) von jeweils einem Horn (61) und einem Amboss (62); und
• Anlegen einer Ultraschallwelle vom Horn (61), um eine Ultraschallverbindungsverarbeitung an dem Werkstück (dem Leiter 21) durchzuführen, in dem
• ein Freigabeelement (H), das Kupfer oder eine Kupferkomponente enthält, zumindest zwischen einem Teil des Werkstücks (dem Leiter 21), das aus Aluminium oder einer Aluminiumlegierung besteht, und der Haltefläche (P) angeordnet ist, wenn das Werkstück (der Leiter 21)) von der Haltefläche (P) gehalten wird.

[1] Ultrasonic joining method, comprising:

• Holding a workpiece (a conductor 21st ), which contains aluminum or an aluminum alloy, through a holding surface ( P ) of one horn each ( 61 ) and an anvil ( 62 ); and
• Applying an ultrasonic wave from the horn ( 61 ) to perform ultrasonic joint processing on the workpiece (the conductor 21st ) in which
• a release element ( H ) containing copper or a copper component, at least between part of the workpiece (the conductor 21st ), which is made of aluminum or an aluminum alloy, and the holding surface ( P ) is arranged when the workpiece (the conductor 21st )) from the holding surface ( P ) is held.

[2] Ultrasonic joining method according to [1], in which the release element ( H ) is a copper foil or a metal foil containing a copper component.

[3] Ultrasonic joining method according to [1], in which the release element ( H ) is a copper powder or a metal powder containing a copper component.

List of reference symbols

11, 13

Electric cables

12

Terminal

21st

Head (workpiece)

22nd

Shell

60

Ultrasonic joining device

61

horn

62

anvil

H

Release element

P

Holding surface

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• JP 4180405 [0003]
• JP 3229379 [0003]

Claims (3)

Ultrasonic joining process comprising: Holding a workpiece containing aluminum or an aluminum alloy by a holding surface each of a horn and an anvil; and Applying an ultrasonic wave from the horn to perform ultrasonic joint processing on the workpiece, wherein a release member containing copper or a copper component is disposed at least between a part of the workpiece made of aluminum or an aluminum alloy and the holding surface when the workpiece is held by the holding surface. Ultrasonic joining method according to Claim 1 wherein the release element is a copper foil or a metal foil containing a copper component. Ultrasonic joining method according to Claim 1 wherein the releasing member is a copper powder or a metal powder containing a copper component.

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