Method for manufacturing a wire with terminals, and a wire with terminals

Abstract

To provide a method for manufacturing wires with terminals that allows for the production of wires with terminals using low-cost and simple equipment. [Solution] A method for manufacturing a terminal-equipped electric wire 1, to which a terminal 20 is connected, comprises the steps of: placing a filler 14 made of a conductive material with a lower melting point than the material constituting the conductor cores 12, adjacent to a plurality of conductor cores 12 of the electric wire 10; heat-pressing the plurality of conductor cores 12 and the filler 14 together to fill the gaps between the plurality of conductor cores 12 with molten filler 14; and crimping the terminal 20 onto a connection portion 15 having the plurality of conductor cores 12 and the filler 14. The plurality of conductor cores 12 are made of aluminum or an aluminum alloy, and the filler 14 is made of tin.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a wire with a terminal, in which a terminal is connected to a wire, and to a wire with a terminal.

Background Art

[0002] Conventionally, from the viewpoint of increasing the allowable current of a wire and improving the bending strength, etc., a wire having a core wire bundle (for example, a stranded wire) in which a plurality of conductor core wires are bundled has been proposed. When a terminal is crimped to such a core wire bundle (stranded wire), the conductor core wires located on the outer peripheral portion of the core wire bundle are directly in contact with the terminal and electrically connected, but the conductor core wires located in the central portion of the core wire bundle are electrically connected to the terminal via the conductors located on the outer peripheral portion. Therefore, in order to improve the overall conductivity between the core wire bundle and the terminal, in addition to the conductivity between the conductor core wire and the terminal (that is, the conductivity of the outer peripheral portion), it is desirable to improve the conductivity between the conductor core wires (that is, the conductivity of the central portion).

[0003] For example, in one of the conventional methods for manufacturing a wire with a terminal, the conductor core wires are joined to each other by performing an ultrasonic bonding process on a core wire bundle made of aluminum conductor core wires, and the core wire bundle is integrated (made into a single wire). As a result, both the conductor core wires located on the outer peripheral portion of the core wire bundle and the conductor core wires located in the central portion substantially come into direct contact with the terminal (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The ultrasonic bonding process described above is typically performed using specialized bonding equipment equipped with a horn (vibrator) that vibrates while applying pressure to the wire core bundle. This type of bonding equipment generally has high initial costs and can complicate the production process in actual operation. For these reasons, there is a need for a more cost-effective and simpler method to produce wires with terminals by single-stranding the wire core bundle.

[0006] One of the objectives of the present invention is to provide a method for manufacturing wires with terminals that can be produced at low cost and with simple equipment, and to provide wires with terminals. [Means for solving the problem]

[0007] To achieve the aforementioned objectives, the method for manufacturing a wire with a terminal and the wire with a terminal according to the present invention are characterized by the following:

[0008] A method for manufacturing a wire with terminals attached, in which terminals are connected to the wire. A step of arranging a filler made of a conductive material having a lower melting point than the material constituting the conductive core wires, adjacent to the plurality of conductive core wires of the electric wire, The process involves heat-pressing the plurality of conductor cores and the filler material together, and placing the molten filler material in the gaps between the plurality of conductor cores. The process includes, in this order, the step of crimping the terminal onto the connection portion having the plurality of conductor cores and the filler material. The method must be a method for manufacturing wires with terminals.

[0009] A wire with a terminal, comprising a wire and a terminal connected to the wire, The aforementioned electric wire is The connector has a plurality of conductive core wires and a filler material which is made of a conductive material and has a lower melting point than the material constituting the conductive core wires, and which is placed in the gaps between the plurality of conductive core wires. The aforementioned terminal is The connection portion is crimped and connected to the electric wire. It must be a wire with terminals. [Effects of the Invention]

[0010] According to the method for manufacturing a wire with terminals of the present invention, a filler material made of a material with a lower melting point and conductivity than the material constituting the wire's conductor core is placed adjacent to the wire's conductor core (for example, after inserting the conductor core into the cylindrical filler), and then the conductor core and the filler are heat-compressed together, so that molten filler is placed in the gaps between multiple conductor cores. Then, a terminal is crimped onto the connection portion having multiple conductor cores and filler. As a result, multiple conductor cores are joined together via the filler and integrated (single-wire), improving the conductivity between the conductor core and the terminal (i.e., conductivity of the outer periphery) and the conductivity between the conductor cores themselves (i.e., conductivity of the central part). Furthermore, this manufacturing method can be carried out using a welding device (for example, a resistance welding machine, so-called bonder) that is generally less expensive to introduce and easier to operate than ultrasonic bonding devices used in conventional manufacturing methods. Therefore, the manufacturing method of the present invention makes it possible to produce wires with terminals at low cost and with simple equipment.

[0011] Furthermore, because the terminal-equipped wire of the present invention has multiple conductor cores joined together via a filler material and integrated (single-wire), it exhibits excellent conductivity between the conductor cores and the terminal (i.e., conductivity of the outer periphery) and between the conductor cores themselves (i.e., conductivity of the central part).

[0012] The present invention has been briefly described above. Further details of the present invention will be clarified by referring to the accompanying drawings and reading through the embodiments for carrying out the invention described below. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a perspective view showing a wire with terminals according to an embodiment of the present invention. [Figure 2] Figure 2 is a perspective view illustrating the process of inserting the bundle of core wires located at the end of an electric wire into a cylindrical filler tube. [Figure 3]FIG. 3 is a first diagram for explaining a step of thermocompression bonding a plurality of conductor cores and a filler that constitute a core wire bundle. [Figure 4] FIG. 4 is a second diagram for explaining a step of thermocompression bonding a plurality of conductor cores and a filler that constitute a core wire bundle. [Figure 5] FIG. 5 is an enlarged view of part A in FIG. 4. [Figure 6] FIG. 6 is a perspective view for explaining a step of crimping a terminal to a connection part of an electric wire composed of a plurality of conductor cores and a filler.

MODE FOR CARRYING OUT THE INVENTION

[0014] <Embodiment> Hereinafter, a method for manufacturing a wire 1 with a terminal according to an embodiment of the present invention (see FIG. 1) will be described with reference to the drawings. The wire 1 with a terminal shown in FIG. 1 includes a wire 10 and a terminal 20 electrically connected to the wire 10. Hereinafter, for convenience of explanation, as shown in FIG. 1 and the like, “front”, “rear”, “left”, “right”, “upper”, and “lower” are defined. The “front-rear direction”, “left-right direction”, and “up-down direction” are orthogonal to each other. Hereinafter, as a preparation for explaining the manufacturing method of the wire 1 with a terminal, first, the configurations of the wire 10 and the terminal 20 used in the manufacturing of the wire 1 with a terminal will be described.

[0015] First, the wire 10 will be described. As shown in FIG. 2, the wire 10 is composed of a core wire bundle 13 having a circular cross-section in which a plurality of conductor cores 12 are bundled, and an insulating coating 11 that covers the outer periphery of the core wire bundle 13. In this example, the conductor core 12 is an unplated solid wire made of aluminum or an aluminum alloy. In other words, the wire 10 is a so-called aluminum wire or aluminum alloy wire.

[0016] Next, the terminal 20 will be described. As shown in FIG. 6, the terminal 20 integrally has an electrical connection portion 21 and a crimp connection portion 22 located on the rear side of the electrical connection portion 21. The terminal 20 is formed by pressing a metal plate made of a conductive metal material such as copper or a copper alloy. Therefore, in this example, the thickness of the terminal 20 is substantially the same at any location.

[0017] The electrical connection portion 21 has a flat connection plate portion 23, and a connection hole 23a is formed in the connection plate portion 23. The connection plate portion 23 is electrically connected to the terminal block, for example, by inserting a fastening bolt through the connection hole 23a and fastening it to the terminal block of the connection device.

[0018] The crimp connection portion 22 has a conductor crimping portion 24 and an outer covering crimping portion 25 in order from the electrical connection portion 21 side (front side). The conductor crimping portion 24 has a base portion 26 and a pair of conductor crimping pieces 27 formed on both side portions of the base portion 26. The connection portion 15 of the electric wire 10 described later is placed on the base portion 26. The conductor crimping piece 27 extends from the base portion 26 so as to sandwich the connection portion 15 of the electric wire 10 before crimping to the electric wire 10. The conductor crimping portion 24 is crimped to the connection portion 15 of the electric wire 10 by bending (crimping) the pair of conductor crimping pieces 27 inward (see FIG. 1).

[0019] The outer covering crimping portion 25 has a base portion 28 and a pair of outer covering crimping pieces 29 formed on both side portions of the base portion 28. The base portion 28 of the outer covering crimping portion 25 extends rearward from the base portion 26 of the conductor crimping portion 24. The terminal portion of the insulating coating 11 of the electric wire 10 is placed on the base portion 28. The outer covering crimping piece 29 extends from the base portion 28 so as to sandwich the insulating coating 11 of the electric wire 10 before crimping to the electric wire 10. The outer covering crimping portion 25 is crimped to the insulating coating 11 of the electric wire by bending (crimping) the pair of outer covering crimping pieces 29 inward (see FIG. 1). Above, the configurations of the electric wire 10 and the terminal 20 used in the manufacture of the electric wire 1 with a terminal have been described.

[0020] The manufacturing method for the wire with terminals 1 will be described below. First, prepare the wire 10, and as shown in Figure 2, strip the insulating coating 11 from the end of the wire 10, exposing a predetermined length of the cylindrical core wire bundle 13, which consists of bundled conductor core wires 12. The predetermined length of the exposed core wire bundle 13 should be sufficient to crimp the terminal 20.

[0021] Next, as shown in Figure 2, a cylindrical filler material 14 is prepared. In this example, the filler material 14 has a continuous cylindrical shape without any breaks in the circumferential direction, but the filler material 14 may have other forms. For example, a plate material may be rolled into a cylindrical shape to form the filler material 14, or multiple rod materials may be arranged around the core wire bundle 13 as the filler material 14. The filler material 14 is made of tin (Sn), which has a melting point (231.96°C) lower than the melting point (660°C) of aluminum (Al) that makes up the core wire bundle 13 (conductor core wire 12) of the electric wire 10. The inner diameter of the cylindrical filler material 14 is set to be slightly larger than the outer diameter of the core wire bundle 13, which has a circular cross-section (cylindrical shape). Then, the cylindrical core wire bundle 13 with the exposed end of the electric wire 10 is inserted into the cylinder of the prepared filler material 14, thereby covering the outer circumference of the exposed core wire bundle 13 with the filler material 14 (see also Figure 3). As a result, the filler material 14, which is made of a material with a lower melting point and conductivity than the material constituting the core wire bundle 13 (conductor core wire 12), is positioned adjacent to the core wire bundle 13 (conductor core wire 12) at the end of the electric wire 10.

[0022] Next, the multiple conductor wires 12 that make up the cylindrical core wire bundle 13 at the end of the electric wire 10 and the cylindrical filler material 14 that covers the outer circumference of the core wire bundle 13 are heat-compressed together. This heat-compression bonding is performed using a welding device (for example, a resistance welding machine, a so-called bonder). Generally, resistance welding machines are less expensive than ultrasonic bonding devices and can be operated at a low cost. As shown in Figures 3 and 4, the resistance welding machine used for heat-compression bonding is equipped with a pair of upper and lower indenters 31 made of conductive material. As shown by the white arrows in Figure 3, the object to be joined (multiple conductor wires 12 + filler material 14) consisting of the multiple conductor wires 12 that make up the core wire bundle 13 at the end of the electric wire 10 and the filler material 14 that covers the multiple conductor wires 12 is pressed and clamped by the pair of upper and lower indenters 31, and a potential difference originating from the power supply 32 is applied between the pair of upper and lower indenters 31. As a result, the object to be joined is pressurized and energized. When current is passed through the objects to be joined, Joule heat is generated in the objects. This Joule heat causes the filler material 14, which has a relatively lower melting point than the multiple conductor cores 12 that make up the objects to be joined, to melt, and the molten filler material 14 enters the gaps between the multiple conductor cores 12 (it is arranged to fill the gaps between the multiple conductor cores 12) (see Figures 4 and 5). As a result, a connection section 15 is formed at the end of the electric wire 10, in which the multiple conductor cores 12 are joined together via the filler material 14 and integrated (single-wire). In this example, the connection section 15 formed at the end of the electric wire 10 has a roughly rectangular parallelepiped shape (see Figures 4 and 6).

[0023] Next, prepare the terminal 20 shown in Figure 6, and crimp the terminal 20 onto the connection portion 15 formed at the end of the electric wire 10. Specifically, the end of the electric wire 10 is placed on the terminal 20 such that the connection portion 15 at the end of the electric wire 10 and the end portion of the insulating sheath 11 are placed on the conductor crimping portion 24 and the outer sheath crimping portion 25 of the terminal 20, respectively. Then, using a crimping device (not shown) equipped with an anvil and a crimper, the pair of conductor crimping pieces 27 of the conductor crimping portion 24 are crimped so that they are curved inward, and the pair of outer sheath crimping pieces 29 of the outer sheath crimping portion 25 are crimped so that they are curved inward, thereby crimping the conductor crimping portion 24 onto the connection portion 15 of the electric wire 10, and crimping the outer sheath crimping portion 25 onto the end portion of the insulating sheath 11 of the electric wire 10 (see Figure 1). From the above, the electric wire 1 with a terminal is completed, and the electric wire 1 with a terminal shown in Figure 1 is obtained.

[0024] In the wire with terminal 1 shown in Figure 1, the connection portion 15 of the wire 10 crimped to the terminal 20 (conductor crimp portion 24) is formed by joining multiple conductor cores 12 together via a filler material 14, thereby integrating them into a single wire. This improves both the conductivity between the conductor cores 12 and the terminal 20 (conductivity of the outer periphery of the core bundle 13) and the conductivity between the conductor cores 12 themselves (conductivity of the central part of the core bundle 13).

[0025] <Effects and Actions> As described above, according to the manufacturing method of the terminal-equipped electric wire 1 according to the embodiment of the present invention, a filler material 14 made of a material that has a lower melting point than the material constituting the conductor core wire 12 of the electric wire 10 and is conductive is placed adjacent to the conductor core wire 12 of the electric wire 10 (for example, after inserting the conductor core wire 12 into the cylinder of the cylindrical filler material 14), and then the conductor core wire 12 and the filler material 14 are heat-pressed together so that the molten filler material 14 is placed in the gaps between the multiple conductor core wires 12. Then, the terminal 20 is crimped onto the connection part 15 having the multiple conductor core wires 12 and the filler material 14. As a result, the multiple conductor core wires 12 are joined together via the filler material 14 and integrated (single-wire), improving both the conductivity between the conductor core wires 12 and the terminal 20 (conductivity of the outer periphery of the core wire bundle 13) and the conductivity between the conductor core wires 12 themselves (conductivity of the central part of the core wire bundle 13). Furthermore, the manufacturing method according to this embodiment can be carried out using a welding device (for example, a resistance welding machine) that is generally less expensive and can be operated at a lower cost compared to ultrasonic bonding devices used in conventional manufacturing methods. Therefore, the manufacturing method of the terminal-equipped wire 1 according to this embodiment makes it possible to produce the terminal-equipped wire 1 with low cost and simple equipment.

[0026] Furthermore, according to the manufacturing method of the terminal-equipped electric wire 1 according to the embodiment of the present invention, the conductor core wire 12 of the electric wire 10 is made of aluminum or an aluminum alloy, and the filler material 14 is made of tin. As a result, when the filler material 14 is heat-welded to the conductor core wire 12, the filler material 14, which is made of tin which has a lower melting point than aluminum or an aluminum alloy, melts, and the molten filler material 14 fills into the gaps between the conductor core wires 12.

[0027] <Other forms> It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the embodiments described above, and can be modified, improved, etc. as appropriate. Furthermore, the material, shape, dimensions, number, placement, etc. of each component in the embodiments described above are arbitrary and not limited as long as they can achieve the present invention.

[0028] For example, in the above embodiment, the conductor core wire 12 of the electric wire 10 is made of aluminum or an aluminum alloy, and the filler material 14 is made of tin. In contrast, any combination of materials can be used to make up the conductor core wire 12 and the filler material 14, as long as the material constituting the filler material 14 has a lower melting point and is electrically conductive than the material constituting the conductor core wire 12.

[0029] Herein, the manufacturing method of the terminal-equipped wire 1 according to the present invention and the features of the embodiments of the terminal-equipped wire 1 are briefly summarized and listed below in [1] to [3].

[0030] [1] A method for manufacturing a terminal-equipped electric wire (1) in which a terminal (20) is connected to an electric wire (10), A step of arranging a filler (14) made of a conductive material and having a lower melting point than the material constituting the conductive core wires (12) so as to be adjacent to the plurality of conductive core wires (12) of the electric wire (10), The process involves heat-pressing the plurality of conductor core wires (12) and the filler material (14) together, and filling the gaps between the plurality of conductor core wires (12) with the molten filler material (14). The process includes, in this order, the step of crimping the terminal (20) onto the connecting portion (15) having the plurality of conductor core wires (12) and the filler material (14), A method for manufacturing an electric wire with terminals (1).

[0031] According to the method for manufacturing a wire with terminals as described in [1] above, a filler material, which has a lower melting point than the material constituting the wire's conductor core and is conductive, is placed adjacent to the wire's conductor core (for example, after inserting the conductor core into the cylindrical filler). Then, the conductor core and the filler are heat-pressed together, so that molten filler is placed in the gaps between multiple conductor cores. A terminal is then crimped onto the connection portion having multiple conductor cores and filler. As a result, multiple conductor cores are joined together via the filler and integrated (single-wire), improving both the conductivity between the conductor core and the terminal (i.e., conductivity of the outer periphery) and the conductivity between the conductor cores themselves (i.e., conductivity of the central part). Furthermore, this manufacturing method can be implemented using a welding device (e.g., a resistance welding machine) which generally has lower introduction costs and is easier to operate than ultrasonic bonding devices used in conventional manufacturing methods. Therefore, this manufacturing method makes it possible to produce wires with terminals at low cost and with simple equipment.

[0032] [2] In the method for manufacturing the terminal-equipped electric wire (1) described in [1] above, The material constituting the conductor core wire (12) includes aluminum or an aluminum alloy. The material constituting the filler (14) includes tin, A method for manufacturing an electric wire with terminals (1).

[0033] According to the method for manufacturing a terminal-equipped electric wire with the configuration described in [2] above, the material constituting the conductor core of the electric wire includes aluminum or an aluminum alloy, and the material constituting the filler includes tin. As a result, when the filler is heat-welded to the conductor core, the filler containing tin, which has a lower melting point than aluminum or an aluminum alloy, melts, and the molten filler fills into the gaps between the conductor cores.

[0034] [3] A terminal-equipped electric wire (1) comprising an electric wire (10) and a terminal (20) connected to the electric wire (10), The aforementioned electric wire (10) is The device has a connecting portion (15) comprising a plurality of conductive core wires (12), and a filler material (14) which is made of a conductive material and has a lower melting point than the material constituting the conductive core wires (12), and which is placed in the gaps between the plurality of conductive core wires (12). The aforementioned terminal (20) is The connection portion (15) is crimped to the electric wire (10), Electrical wire with terminals (1).

[0035] In the terminal-equipped wire configuration described in [3] above, a filler material, which has a lower melting point than the material constituting the conductor core of the wire and is also conductive, is arranged to fill the gaps between the multiple conductor cores. Furthermore, the wire is crimped to the connection part having the multiple conductor cores and the filler material. As a result, the multiple conductor cores are joined together via the filler material and integrated (single-wire). Therefore, the conductivity between the conductor core and the terminal of the terminal-equipped wire (i.e., conductivity of the outer periphery) and the conductivity between the conductor cores themselves (i.e., conductivity of the central part) can be improved. [Explanation of Symbols]

[0036] 1. Wire with terminals 10 Electric wire 12 Conductor core wires 14 Filling material 15 Connection part 20 terminals

Claims

1. A method for manufacturing a wire with terminals attached, in which terminals are connected to the wire. A step of arranging a filler made of a conductive material having a lower melting point than the material constituting the conductive core wires, adjacent to the plurality of conductive core wires of the electric wire, The process involves heat-pressing the plurality of conductor cores and the filler material together, and placing the molten filler material in the gaps between the plurality of conductor cores. The process includes, in this order, the step of crimping the terminal onto the connection portion having the plurality of conductor cores and the filler material. A method for manufacturing wires with terminals.

2. In the method for manufacturing a wire with terminals according to claim 1, The material constituting the aforementioned conductor core wire includes aluminum or an aluminum alloy. The material constituting the filler includes tin, A method for manufacturing wires with terminals.

3. A wire with a terminal, comprising a wire and a terminal connected to the wire, The aforementioned electric wire is The connector has a plurality of conductive core wires and a filler material which is made of a conductive material and has a lower melting point than the material constituting the conductive core wires, and which is placed in the gaps between the plurality of conductive core wires. The aforementioned terminal is, The connection portion is crimped and connected to the electric wire. Electrical wire with terminals.

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