JP2006024523A - Connection terminal, ultrasonic connection device and method, and connection part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light and highly conductive connection terminal and a connection part, and provide an ultrasonic connection device and an ultrasonic connection method. <P>SOLUTION: The connection terminal 11 is connected to an aluminum conductor 12. It is constituted of a composite material obtained by laminating and cladding at least two layers of an Al layer 21 composed mainly of Al and a Cu layer 22 composed mainly of Cu, wherein the Al layer 21 is disposed on a contacting part with the aluminum conductor 12. The connection part 10 is constituted by connecting the connection terminal 11 and the aluminum conductor 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a connection terminal for an automobile cable, particularly a battery cable.

As shown in FIG. 7, a connection portion for an automobile cable, for example, a battery cable or a wire harness, is obtained by placing a cable conductor 72 on a connection terminal 71 and ultrasonically connecting a hatched area 73. Conventionally, Cu has been used as a constituent material of the connection terminal 71 and the cable conductor 72. This is because Cu has high conductivity (conductivity: about 5.8 × 10 ³ S / m).

  In recent years, in automobiles, since weight reduction and recyclability are required, Al has begun to be used as a constituent material of the connection terminal 71 and the cable conductor 72 in the connection portion 70 (see Patent Document 1).

JP 2004-111058 A

  By the way, when the connection terminal 71 is made of Al, since Al is inferior in conductivity to Cu, there is a problem that a temperature rise due to resistance heat generation occurs in the connection portion 70. As a result, the connection portion 70 may be broken or may be disconnected due to insufficient high-temperature strength.

  An object of the present invention created in view of the above circumstances is to provide a connection terminal, an ultrasonic connection device, a method, and a connection portion that are lightweight and have good conductivity.

  In order to achieve the above object, the connection terminal according to the present invention is a connection terminal connected to an aluminum conductor, wherein an Al layer containing Al as a main component and a Cu layer containing Cu as a main component are laminated in two or more layers. It is composed of a clad composite material, and the Al layer is disposed at the contact portion with the aluminum conductor.

  Here, the layer thickness ratio TAl / TCu between the Al layer and the Cu layer is preferably 0.01 or more and 1.0 or less. Moreover, the connection terminal comprised with a composite material is provided with the main-body part which mounts an aluminum conductor, and the conductor holding | suppressing part formed by bending a part of the main-body part.

  An ultrasonic connecting device according to the present invention is a device that applies ultrasonic vibrations via a horn chip provided at the tip of an ultrasonic horn and ultrasonically connects objects to be connected. The device has an inclination angle with respect to the connected object.

  The ultrasonic connection method according to the present invention is a method of applying ultrasonic vibration through a horn chip provided at the tip of an ultrasonic horn and ultrasonically connecting objects to be connected. Then, it is brought into contact with the connected object in an inclined state to apply ultrasonic waves.

  The connection part according to the present invention is formed by connecting the connection terminal described above and an aluminum conductor. Moreover, the connection part which concerns on this invention connects a connection terminal and an aluminum conductor using the ultrasonic connection apparatus mentioned above. Furthermore, the connection part which concerns on this invention connects a connection terminal and an aluminum conductor using the ultrasonic connection method mentioned above.

  Here, the aluminum conductor is a stranded conductor composed of an Al strand or an Al alloy strand.

  According to the present invention, it is possible to obtain a connection terminal that is lighter than a connection terminal composed of Cu alone and has substantially the same conductivity as a connection terminal composed of Cu alone. Demonstrate.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of the invention will be described with reference to the accompanying drawings.

  1 is a plan view of a connection terminal according to a preferred embodiment of the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a sectional view taken along line 3-3 of FIG.

  As shown in FIG. 1, the connection terminal 11 according to the present embodiment includes an aluminum conductor 12 of a cable end, specifically, a stranded conductor (or a single conductor) composed of an Al strand or an Al alloy strand. It is connected, and is composed of a composite material in which an Al layer 21 mainly composed of Al and a Cu layer 22 mainly composed of Cu are laminated and clad in two or more layers. The Al layer 21 of this composite material is disposed on the contact portion side with the aluminum conductor 12 (inner layer side in FIG. 1).

  As shown in FIG. 2, the connection terminal 11 includes a main body portion 31 on which the aluminum conductor 12 is placed, and conductor pressing portions 32 a and 32 b formed by bending a part of the main body portion 31. Specifically, as shown in FIG. 3, both end portions in the width direction of the main body portion 31 (left and right end portions in FIG. 3) are bent at right angles to form conductor pressing portions 32a and 32b.

  The layer thickness ratio TAl / TCu between the Al layer 21 and the Cu layer 22 is set to 0.01 ≦ TAl / TCu ≦ 1.0, preferably 0.1 ≦ TAl / TCu ≦ 1.0. If TAl / TCu exceeds 1.0, the conductivity deteriorates, and the temperature rises due to resistance heat generation at the connection portion 10, so that the Al layer 21 has the same maximum layer thickness as the Cu layer 22. Is done.

  The shape and size of the space S surrounded by the main body portion 31 and the conductor pressing portions 32 a and 32 b are appropriately determined according to the shape and size of the aluminum conductor 12, but there are gaps between the space S and the aluminum conductor 12. It is preferable to adhere so that no is formed.

  Next, the case where the connection terminal 11 and the aluminum conductor 12 according to the present embodiment are connected using an ultrasonic connection device to produce a connection portion will be described.

  First, FIG. 4 shows a schematic diagram of an ultrasonic connection device according to a preferred embodiment of the present invention used for ultrasonic connection.

  As shown in FIG. 4, the ultrasonic connection device 40 according to the present embodiment mainly includes a main body 41 and an ultrasonic oscillator 47. The main body 41 is composed of a horn support 42 provided on a base 49 and an anvil 43, and a horn chip 45 is provided at the tip of an ultrasonic horn 44 extending horizontally from the horn support 42. As shown in FIG. 5 which is an enlarged view of the main part 5 of FIG. 4, the horn chip 45 has a tip surface (lower surface in FIG. 5) 45a with respect to the horizontal plane F of the connected object (the aluminum conductor 12 and the main body 31). Is inclined by a predetermined angle θ. The inclination angle θ of the front end face 45a is determined as appropriate according to the size of the aluminum conductor 12, and increases as the size of the aluminum conductor 12 increases. For example, the inclination angle θ is 0 to 30 ° (excluding 0 °), preferably 10 to 20 °. The tip surface 45a referred to here is a surface obtained by averaging the inclinations of the entire tip of the horn chip 45.

  The object to be connected is placed on the anvil 43 of the ultrasonic connection device 40 having such a configuration, and the tip surface 45a of the horn chip 45 is brought into contact with the object to be connected, so that the ultrasonic oscillator 47 oscillates. The ultrasonic vibration thus applied is applied to the connected object.

  Here, as shown in FIG. 6, when a conventional ultrasonic connecting device having a flat tip surface of the horn chip 65 is used, the region 61 (the ultrasonic wave applying region in the aluminum conductor 12 (the hatched region 13 in FIG. 1) is used. ) And the non-applied region (in the vicinity of the boundary portion), the aluminum conductor 12 is crushed (or completely extended), and the aluminum element wire is disconnected.

  However, in the ultrasonic connection method using the ultrasonic connection device 40 according to the present embodiment, the tip surface 45a of the horn chip 45 is inclined at an angle θ with respect to the connected object, as shown in FIG. The contact is made in the state, and ultrasonic waves are applied. For this reason, crushing of the aluminum conductor 12 is suppressed in the vicinity of the boundary portion between the ultrasonic wave application region and the non-application region in the aluminum conductor 12 (region 51 in FIG. 5). As a result, there is no possibility of disconnection of the aluminum wire in the aluminum conductor 12 during ultrasonic connection.

  In addition, when ultrasonically connecting an ordinary Cu connection terminal and an aluminum conductor, since the connection is made between different materials, the applied energy at the time of ultrasonic connection must be increased. As a result, there has been a problem that due to the high temperature at the time of energy application, the deformation of the aluminum conductor is increased and the conductor strength is lowered, and consequently the connectivity is lowered.

  However, in the connection terminal 11 according to the present embodiment, the connection terminal is formed of a composite material of the Al layer 21 and the Cu layer 22 and the Al layer 21 is disposed on the surface on the contact portion side with the aluminum conductor 12. Yes. Thereby, in the ultrasonic connection part, since it becomes a connection between the same kind of materials, the applied energy at the time of ultrasonic connection can be made small. As a result, it is possible to prevent a decrease in the conductor strength of the aluminum conductor 12 and thus improve the connectivity.

  Further, the connection terminal 11 is composed of a composite material of the Al layer 21 and the Cu layer 22 and the layer thickness ratio TAl / TCu between the Al layer 21 and the Cu layer 22 is adjusted to 1.0 or less. For this reason, the connection terminal 11 has sufficient electrical conductivity substantially equal to the connection terminal formed of Cu alone. As a result, the connection portion 10 does not increase in temperature due to resistance heat generation, and there is no possibility of disconnection due to deformation or insufficient high-temperature strength.

  Further, the surface of the connection terminal on the non-contact portion side with the aluminum conductor (hereinafter referred to as a non-contact surface) is connected to the connector terminal of the product to be connected (for example, battery). This connector terminal is made of Cu. There are often. In the connection terminal 11 according to the present embodiment, the Cu layer 22 is disposed on the non-contact surface. For this reason, the non-contact surface of the connection terminal 11 and the connector terminal are in contact between the same kind of materials. Therefore, there is no possibility of potential difference corrosion occurring at the connection portion of each terminal.

  Furthermore, the contact part with the aluminum conductor 12 in the connection terminal 11 is formed in a cross-sectional saddle shape (U shape) by the main body part 31 and the conductor pressing parts 32a and 32b. Since the conductor holding portions 32a and 32b restrain the aluminum conductor 12 at the time of ultrasonic connection, the stranded wire is not scattered when the aluminum conductor 12 composed of a twisted Al strand is ultrasonically connected. . Moreover, since the connection area | region of the connection terminal 11 and the aluminum conductor 12 becomes three planes of the main-body part 31 and the conductor holding | suppressing parts 32a and 32b, a contact area is large, As a result, the connection terminal 11 and the aluminum conductor 12 are Connectivity is improved.

  As described above, the present invention is not limited to the above-described embodiment, and it goes without saying that various other things are assumed.

  Next, although this invention is demonstrated based on an Example, this invention is not limited to these Examples.

Example 1
A copper plate and an aluminum plate were laminated and rolled to produce a composite plate material having a thickness of 1.0 mm. This composite plate material had an Al layer thickness of 0.1 mm, a Cu layer thickness of 0.9 mm, and TAl / TCu of 0.11.

(Example 2)
A copper plate and an aluminum plate were laminated and rolled to produce a composite plate material having a thickness of 1.0 mm. This composite plate material had an Al layer thickness of 0.5 mm, a Cu layer thickness of 0.5 mm, and TAl / TCu of 1.00.

(Comparative Example 1)
A plate material having a thickness of 1.0 mm was produced by rolling using only a copper plate.

  Table 1 shows the specifications (plate thickness, Al layer and Cu layer thickness (Al layer / Cu layer), TAl / TCu) of the plate materials of Examples 1 and 2 and Comparative Example 1.

  Next, the plate materials of Examples 1 and 2 and Comparative Example 1 were cut into strip-shaped test pieces having a width of 20 mm and a length of 30 mm. Both ends in the width direction of these test pieces were bent inward by 90 ° with a width of 5 mm, and a simulated body of the connection terminal 11 shown in FIG. 1 was produced. Each simulated body and the aluminum conductor were connected using the ultrasonic connection apparatus 40 shown in FIG. 4, and the connection part was produced. As the aluminum conductor, a stranded wire conductor obtained by twisting 19 Al strands having an outer diameter of φ1.0 mm was used. As the horn chip (male shape) 45 in the ultrasonic connecting device 40, a tip having an inclined tip surface was used, and the tip surface size was set to 10 mm × 8 mm. The ultrasonic connection conditions were a frequency of 40 kHz, a pressure of 0.1 to 0.4 MPa, and an ultrasonic wave application energy of 1 to 3000 J.

  The connectivity of the connection part after ultrasonic connection was evaluated. The evaluation results (ultrasound application energy, tensile strength, peel strength (peeling strength), lightness, and overall evaluation thereof) are shown in Table 2. As for the energy applied to ultrasonic waves, the energy required for connection was high, and the energy required for connection was low. The tensile strength is expressed as an actual tensile strength and a relative value when the base material strength (120 MPa) of the aluminum conductor is 1.0. The peel strength is expressed as a relative value when the base material strength (120 MPa) of the aluminum conductor is 1.0. Regarding lightness and comprehensive evaluation, a good one was marked as ◯, and an insufficient one was marked as △.

  As shown in Table 2, the connection between the simulated body using the plate material of Comparative Example 1 and the aluminum conductor has a tensile strength of 120 MPa (relative value is 1.0), a peel strength of 0.5, and a sufficient tensile strength and peel. Had strength. However, since the connection between the simulated body and the aluminum conductor is between different materials, the ultrasonic application energy required for the connection was high. Moreover, since this simulation body was comprised only with Cu, the lightness was inadequate. Therefore, comprehensive evaluation was also insufficient.

  On the other hand, the connection part between the simulated body using each composite plate material of Examples 1 and 2 and the aluminum conductor has the same tensile strength and peel strength as in Comparative Example 1, and has sufficient tensile strength and peel strength. Had. In addition, since the connection between the simulated body and the aluminum conductor is between the same kind of materials, the ultrasonic application energy required for the connection was low. Furthermore, since these simulated bodies are composed of a composite material of Al and Cu, the lightness is good as compared with the simulated body of Comparative Example 1 composed of Cu alone. Therefore, the overall evaluation was also good.

  Two simulated bodies prepared using each composite plate material of Examples 1 and 2 were prepared. Each one of the simulated bodies was ultrasonically connected to the aluminum conductor using an ultrasonic connection device in which the tip surface of the horn chip 45 was inclined (Examples 1 and 2). Further, each of the other simulated bodies was subjected to ultrasonic connection with an aluminum conductor using an ultrasonic connection device having a flat tip surface of the horn chip 45 (Comparative Examples 2 and 3).

  The connectivity of each connection part after ultrasonic connection was evaluated. Table 3 shows the evaluation results (appearance evaluation such as crushing of the aluminum conductor, specifically, presence / absence of Al wire breakage).

  As shown in Table 3, no Al wire breakage was observed in the connection portion between the simulated body using each composite plate material of Examples 1 and 2 and the aluminum conductor. In contrast, Al wire breakage was observed at the connection between the simulated body using each composite plate material of Comparative Examples 2 and 3 and the aluminum conductor.

  Therefore, it was confirmed that when the tip end surface of the horn chip is brought into contact with the connected object in an inclined state and ultrasonic waves are applied, the aluminum element does not break in the aluminum conductor.

1 is a plan view of a connection terminal according to a preferred embodiment of the present invention. It is a side view of FIG. FIG. 3 is a sectional view taken along line 3-3 in FIG. 2. 1 is a schematic view of an ultrasonic connection device according to a preferred embodiment of the present invention. It is a principal part enlarged view of FIG. It is a principal part enlarged view of the conventional ultrasonic connection apparatus. It is a top view of the conventional connection terminal.

Explanation of symbols

11 Connection terminal 12 Aluminum conductor 21 Al layer 22 Cu layer

Claims (9)

  In the connection terminal connected to the aluminum conductor, the aluminum conductor is composed of a composite material obtained by laminating and clad two or more layers of an Al layer containing Al as a main component and a Cu layer containing Cu as a main component. A connection terminal characterized in that the Al layer is disposed at a contact portion of the contact.   The connection terminal according to claim 1, wherein a layer thickness ratio TAl / TCu between the Al layer and the Cu layer is 0.01 or more and 1.0 or less.   The connection terminal according to claim 1, further comprising: a main body portion on which the aluminum conductor is placed; and a conductor pressing portion formed by bending a part of the main body portion.   In an apparatus for applying ultrasonic vibration via a horn tip provided at the tip of an ultrasonic horn and ultrasonically connecting the connected objects, the tip surface of the horn tip is inclined with respect to the connected object. An ultrasonic connecting device comprising:   In a method of applying ultrasonic vibration through a horn chip provided at the tip of an ultrasonic horn and ultrasonically connecting objects to be connected, the tip surface of the horn chip is inclined with respect to the object to be connected. An ultrasonic connection method, wherein the ultrasonic wave is applied in a state of contact with each other and ultrasonic waves are applied.   A connection portion comprising the connection terminal according to claim 1 and an aluminum conductor.   A connecting portion comprising a connecting terminal and an aluminum conductor connected using the ultrasonic connecting device according to claim 4.   A connection portion comprising a connection terminal and an aluminum conductor connected using the ultrasonic connection method according to claim 5. The connection part according to any one of claims 6 to 8, wherein the aluminum conductor is a stranded conductor composed of an Al strand or an Al alloy strand.

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