JP6386730B2 - Aluminum conductor surface treatment method, surface treatment apparatus, and aluminum conductor - Google Patents

Description

  The present invention relates to a surface treatment method and a surface treatment apparatus for an aluminum conductor, and an aluminum conductor.

  In recent years, in order to reduce the weight of a wire harness routed in an automobile, it has been considered to employ a light aluminum wire instead of a conventional copper wire. As shown in FIG. 7, the aluminum electric wire 100 includes an aluminum stranded wire portion 100A and an insulating coating portion 100B that covers the aluminum stranded wire portion 100A.

  However, since aluminum has a strong oxide film on its surface, contact resistance between the aluminum wire and the terminal may increase over time if a connection method similar to that of current copper wires, such as crimping, is used for terminal connection. there were. Therefore, in order not to increase the contact resistance between the aluminum electric wire and the terminal, it is necessary to remove the oxide film on the aluminum surface at the portion connected to the terminal.

  Therefore, it is considered to form a solder plating layer in a state in which the oxide film is removed on both ends of the aluminum stranded wire portion 100A made of aluminum using ultrasonic soldering techniques as shown in Patent Documents 1 to 3. It has been. In addition, in the intermediate part of the aluminum twisted wire part 100A, in order to strengthen protection, it is desired to leave an oxide film.

  For this reason, the solder plating layer was formed in the edge part of the aluminum twisted-wire part 100A which comprises the aluminum electric wire 100 in the procedure as shown below. First, the insulation coating portions 100B at both ends of the aluminum electric wire 100 are removed to expose both ends of the aluminum stranded wire portion 100A. Thereafter, one of the two ends of the exposed aluminum stranded wire portion 100A is dipped in the solder tank 300 in which the ultrasonic vibration plate 200 is installed.

  When ultrasonic vibration is applied using the ultrasonic vibration plate 200, a solder plating layer is formed in a state where the oxide film of the aluminum stranded wire portion 100A immersed in the solder bath 300 is removed. Similarly, the other end of the exposed aluminum stranded wire portion 100A is immersed in the solder bath 300 to form a solder plating layer. As a result, a solder plating layer is formed on both ends of the exposed aluminum stranded wire portion 100A with the oxide film removed, and an intermediate portion of the aluminum stranded wire portion 100A covered with the insulating coating portion 100B has an oxide film. Can be left.

JP-A-9-143671 JP 58-97479 A Japanese Patent Laid-Open No. 61-115658

  However, the above-described surface treatment method for an aluminum electric wire has a problem that it is necessary to immerse both ends of an aluminum stranded wire portion in a solder tank in order to form a solder plating layer, which requires work time. In addition, when aluminum wires composed of rod-shaped aluminum materials are used instead of aluminum stranded wires, aluminum materials cannot be bent, so it is difficult to immerse both ends of the aluminum material separately in a solder bath, which is automated. There was also a problem that it was not suitable.

  Therefore, an object of the present invention is to provide a surface treatment method and a surface treatment apparatus for an aluminum conductor, and an aluminum conductor, which can shorten the working time.

  The invention according to claim 1 for solving the above-mentioned problem is a method for treating a surface of an aluminum conductor in which a solder plating layer is formed on the surface of a long aluminum conductor used as an electric wire. The entire aluminum conductor is soaked in the solder tank so that only both ends of the aluminum conductor are opposed to a pair of ultrasonic diaphragms installed in the vibrator, and the ultrasonic diaphragm is vibrated, The solder plating layer is formed in a state in which only the oxide film on both ends of the aluminum conductor is removed, and the solder plating layer is formed in a state in which the oxide film in the intermediate part of the aluminum conductor is left. It exists in the surface treatment method of the aluminum conductor.

  The invention according to claim 2 is a surface treatment apparatus for an aluminum conductor that forms a solder plating layer on the surface of a long aluminum conductor used as an electric wire, and is installed in the solder tank and the solder tank. A pair of ultrasonic diaphragms in which both ends of the aluminum conductor are opposed to each other, and a first support part that is installed between the pair of ultrasonic diaphragms in the solder tank and supports the aluminum conductor; The present invention resides in a surface treatment apparatus for an aluminum conductor.

  According to a third aspect of the present invention, there is provided a second support portion composed of a conductive member that detachably supports both ends of the aluminum conductor and takes the aluminum conductor into and out of the solder tank, and the second support. The apparatus according to claim 2, further comprising: a determination unit that determines whether or not the oxide film is removed at both ends of the aluminum conductor by passing a current through the aluminum conductor through the section. It exists in the surface treatment apparatus of a conductor.

The invention according to claim 4 is a long aluminum conductor used as an electric wire, and at both ends in the longitudinal direction, a solder plating layer is formed on the surface with the oxide film removed, and the both ends Oite to all surfaces of the central portion excluding the resides in the aluminum conductor, characterized in that the solder plating layer is formed on the surface while leaving the oxide film.

  As described above, according to the first, second, and fourth aspects of the invention, the oxide film on both ends can be removed simply by immersing the entire aluminum conductor in the solder bath, so that the working time can be shortened. it can. Further, since the ultrasonic vibration plate is partially provided by disposing the sound vibration plate only at both ends of the aluminum conductor, the cost can be reduced. In addition, since the solder plating layer is formed in a state where the oxide film in the intermediate portion of the aluminum conductor is left, protection from mechanical external force in the intermediate portion can be enhanced.

  According to the third aspect of the present invention, the determination means determines whether or not the oxide film is removed at both ends of the aluminum conductor by flowing current through the aluminum conductor via the second support portion. When the aluminum conductor is taken out of the solder tank using the support portion, it is possible to make a pass / fail judgment, and the working time can be further reduced.

It is a figure which shows one Embodiment of the surface treatment apparatus of the aluminum conductor of this invention. It is a perspective view which shows the detail of the holding stand shown in FIG. (A) is a perspective view which shows the detail of the suspension part shown in FIG. 1, (B) is a modification of a suspension part. (A) is a longitudinal cross-sectional view of the aluminum conductor before surface treatment, (B) is a longitudinal cross-sectional view of the aluminum conductor after surface treatment. It is a figure for demonstrating the surface treatment method of the aluminum conductor of this invention. It is a figure which shows the surface treatment apparatus of the aluminum conductor of this invention in other embodiment. It is a figure for demonstrating the surface treatment method of the conventional aluminum conductor.

  Hereinafter, a surface treatment apparatus for an aluminum conductor according to the present invention will be described with reference to FIGS. The aluminum conductor subjected to surface treatment in the present invention is used as an electric wire routed in an automobile to supply power, and terminal fittings are crimped (connected) to both ends thereof. As shown in FIG. 2 and the like, the aluminum conductor 1 is made of aluminum and is formed in a long bar shape having a circular cross section.

  As shown in FIG. 4A, the aluminum conductor 1 before the surface treatment has an oxide film 2 formed on the entire surface. As shown in FIG. 4 (B), the aluminum conductor surface treatment apparatus 3 (hereinafter simply referred to as surface treatment apparatus) 3 shown in FIG. 1 is oxidized at both ends where the terminal fitting is pressed against the surface of the aluminum conductor 1. This is an apparatus for removing the coating film 2 and forming the solder plating layer 5 with the oxide film 2 left in the middle part.

  As shown in FIG. 1 and the like, the surface treatment apparatus 3 includes a solder bath 31, a pair of ultrasonic vibration plates 32 installed in the solder bath 31, and opposite ends of the aluminum conductor 1, and solder. A holding base 33 (= first support portion) that is installed between a pair of ultrasonic vibration plates 32 of the tank 31 and supports the intermediate portion of the aluminum conductor 1 and detachably supports both ends of the aluminum conductor 1. And a hanging part 34 (= second support part) for taking the aluminum conductor 1 into and out of the solder bath 31.

  The solder bath 31 is provided in such a size that the solder solution 35 is stored and the entire aluminum conductor 1 can be immersed in the solder solution 35. The pair of ultrasonic diaphragms 32 is provided in a plate shape, and the thickness direction thereof is arranged along the vertical direction, and the aluminum conductors 1 are arranged side by side at intervals in the longitudinal direction. An ultrasonic transducer (not shown) is fixed to the pair of ultrasonic diaphragms 32. When the ultrasonic transducer vibrates, the ultrasonic diaphragm 32 vibrates.

  The holding table 33 is provided in a substantially rectangular parallelepiped shape along the longitudinal direction of the aluminum conductor 1, and a groove 33A having a semicircular cross section is provided on the upper surface thereof. The groove 33A is provided along the longitudinal direction of the aluminum conductor 1, and the aluminum conductor 1 is fitted and supported in the groove 33A. The length of the holding table 33 in the longitudinal direction is shorter than the length of the aluminum conductor 1 in the longitudinal direction. As a result, when the intermediate portion of the aluminum conductor 1 is held by the holding base 33, both end portions of the aluminum conductor 1 protrude from the holding base 33 and face the ultrasonic vibration plate 32 as shown in FIG. Be placed. In the example shown in FIG. 1, both end portions of the aluminum conductor 1 and the ultrasonic vibration plate 32 are spaced apart from each other, but both end portions of the aluminum conductor 1 and the ultrasonic vibration plate 32 are in contact with each other. Also good.

  As shown in FIG. 4A, a pair of hanging portions 34 are arranged side by side in the longitudinal direction of the aluminum conductor 1, and a clip portion 34A that can be freely opened and closed (detached) is provided at the tip thereof. By closing the clip portion 34A, the both ends of the aluminum conductor 1 are grasped and supported, and by opening the clip portion 34A, the aluminum conductor 1 can be removed.

  The hanging portion 34 is not limited to the clip portion 34A shown in FIG. 4 (A), but has a hook portion 34B provided at the tip thereof as shown in FIG. 4 (B). Also good.

  Next, a surface treatment method for the aluminum conductor 1 using the surface treatment apparatus 3 described above will be described with reference to FIG. First, as shown in FIG. 5A, both end portions of the aluminum conductor 1 before surface treatment are supported by the suspending portion 34, and the suspending portion 34 is moved above the solder bath 31. Thereafter, the suspending portion 34 is moved downward, and the intermediate portion of the aluminum conductor 1 is supported by the holding base 33 as shown in FIG. As a result, the entire aluminum conductor 1 is immersed in the solder bath 31, and both ends of the aluminum conductor 1 face the ultrasonic vibration plate 32.

  Thereafter, as shown in FIG. 5C, the aluminum conductor 1 is removed from the suspending portion 34, the suspending portion 34 is moved upward, and is taken out from the solder bath 31. Next, the ultrasonic vibration plate 32 is vibrated by vibrating an ultrasonic vibration (not shown). Thereby, it is possible to remove the oxide film 2 only at both ends facing the ultrasonic vibration plate 32 while leaving the oxide film 2 at the intermediate portion of the aluminum conductor 1.

  Thereafter, the suspended portion 34 is immersed in the solder bath 31 to support both ends of the aluminum conductor 1 again. Next, as shown in FIG. 5E, the hanging portion 34 is moved upward to take out the aluminum conductor 1 from the solder bath 31. As shown in FIG. 4B, a solder plating layer 5 is formed on the surface of the pulled aluminum conductor 1 with the oxide film 2 only at both ends removed, and an intermediate oxide film 2 is formed. The solder plating layer 5 is formed in a state in which is left. As a result, the intermediate portion of the aluminum conductor 1 is coated with two layers of the oxide film 2 and the solder plating layer 5.

  Each of the suspension parts 34 described above is made of a conductive member, and is connected to the determination part 6 (= determination means) as shown in FIG. The determination unit 6 determines whether or not the oxide film 2 is removed at both ends of the aluminum conductor 1 by causing a current to flow through the aluminum conductor 1 via the suspension unit 34. More specifically, the determination unit 6 includes, for example, a current source that allows current to flow through the aluminum conductor 1 via the suspension unit 34, and the resistance value of the aluminum conductor 1 is determined from the voltage generated between the pair of suspension units 34. Ask for. If the resistance value is small, the determination unit 6 determines that the oxide film 2 is cleanly removed, and if the resistance value is large, the determination unit 6 determines that the oxide film 2 is not cleanly removed. Thereafter, the aluminum conductor 1 determined as a non-defective product is completed by providing an insulating coating layer on the portion excluding both ends.

  According to the above-described embodiment, the entire aluminum conductor 1 is placed in the solder tank 31 so that only both ends of the aluminum conductor 1 are opposed to the pair of ultrasonic diaphragms 32 installed in the solder tank 31. Then, the ultrasonic vibration plate 32 is vibrated to form the solder plating layer 5 in a state where the oxide film 2 only at both ends of the aluminum conductor 1 is removed, and the oxide film 2 at the intermediate part of the aluminum conductor 1. The solder plating layer 5 is formed while leaving Thereby, since the oxide film 2 of both ends can be removed only by immersing the whole aluminum conductor 1 in the solder tank 31, work time can be shortened. Moreover, since the ultrasonic vibration plate 32 is partially provided by disposing the ultrasonic vibration plate 32 only at both ends of the aluminum conductor 1, the cost can be reduced. In addition, since the solder plating layer 5 is formed with the oxide film 2 in the intermediate portion of the aluminum conductor 1 remaining, protection from mechanical external force in the intermediate portion can be enhanced.

  Further, according to the above-described embodiment, the determination unit 6 determines the quality of the solder plating layer 5 by causing a current to flow through the aluminum conductor 1 via the suspension unit 34. As a result, it is possible to determine whether or not the aluminum conductor 1 is taken out of the solder tank 31 using the hanging portion 34, and the working time can be further reduced.

  Further, according to the above-described embodiment, the aluminum conductor 1 is a rod-shaped one. Thereby, it does not deform like a stranded wire and is easy to automate.

  In addition, according to embodiment mentioned above, as the aluminum conductor 1, the rod-shaped thing with a circular cross section was used, However, It is not restricted to this. The aluminum conductor 1 may be long and may be formed in a strip shape.

  Moreover, according to embodiment mentioned above, although the determination part 6 sent the electric current through the aluminum conductor 1 using the current source, it is not restricted to this. A current may be passed through the aluminum conductor 1 using a voltage source.

  Further, according to the above-described embodiment, the aluminum conductor 1 is supported by the single holding stand 33, but the present invention is not limited to this. For example, as shown in FIG. 6, the aluminum conductor 1 may be supported by a plurality of holding bases 33 (two in the example shown in FIG. 6) spaced apart in the longitudinal direction of the aluminum conductor 1. Further, in this case, as in the above embodiment, a plurality of holding bases 33 may be provided between the pair of hanging portions 34, and as shown in FIG. A holding stand 33 may be provided.

  Moreover, according to embodiment mentioned above, although the suspension part 34 supported the part which protrudes from the holding stand 33 among the aluminum conductors 1, it is not restricted to this. As the suspending portion 34, an inner portion of the holding base 33 of the aluminum conductor 1 may be supported.

  Further, according to the above-described embodiment, the terminal fitting is crimped to the end portion of the aluminum conductor 1, but this is not a limitation. The present embodiment can also be applied to the aluminum conductor 1 that is directly connected to a substrate or the like.

  Further, the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Aluminum conductor 2 Oxide film 3 Surface treatment apparatus 5 Solder plating layer 6 Determination part (determination means)
31 Solder tank 32 Ultrasonic vibration plate 33 Holding stand (first support part)
34 Hanging part (second support part)

Claims (4)

A surface treatment method for an aluminum conductor that forms a solder plating layer on the surface of a long aluminum conductor used as an electric wire,
The entire aluminum conductor is immersed in the solder tank so that only both ends of the aluminum conductor are opposed to a pair of ultrasonic vibration plates installed in the solder tank,
The ultrasonic vibration plate is vibrated to form the solder plating layer in a state in which only the oxide film on both ends of the aluminum conductor is removed, while leaving the oxide film in the intermediate part of the aluminum conductor. A method for treating the surface of an aluminum conductor, comprising forming the solder plating layer. A surface treatment apparatus for an aluminum conductor that forms a solder plating layer on the surface of a long aluminum conductor used as an electric wire,
A solder bath,
A pair of ultrasonic diaphragms installed in the solder bath and oppositely disposed at both ends of the aluminum conductor;
A first support part installed between the pair of ultrasonic diaphragms in the solder tank and supporting the aluminum conductor;
An aluminum conductor surface treatment apparatus characterized by comprising: A second support portion configured by a conductive member that detachably supports both ends of the aluminum conductor and takes the aluminum conductor into and out of the solder tank; and
A determination means for determining whether or not the oxide film is removed at both ends of the aluminum conductor by passing a current through the aluminum conductor through the second support portion;
The surface treatment apparatus for an aluminum conductor according to claim 2, comprising: A long aluminum conductor used as an electric wire,
In both ends in the longitudinal direction, the solder plating layer is formed on the surface while removing the oxide film, Oite to all surfaces of the central portion excluding the both end portions, the surface, leaving an oxide film An aluminum conductor having a solder plating layer formed thereon.

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