JP2011134515A - Electric wire with terminal fitting, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric wire with a small-size terminal fitting capable of preventing disconnection of an element wire with a good connection state between the electric wire and the terminal. <P>SOLUTION: An electric wire 10 with a terminal fitting includes an electric wire 11 containing core wires 12 comprising a plurality of element wires, and a terminal fitting 20 connected to the core wire 12 exposed from the end portion of the electric wire 11. The terminal fitting 20 is provided with a welding part 21 which is welded to the core wire 12 by ultrasonic welding. The welding part 21 is inserted into the vicinity of center in the radial direction of the electric wire 11 from the end part side of the core wire 12 along the direction the electric wire 11 extends. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electric wire with a terminal fitting and a method for manufacturing an electric wire with a terminal fitting.

  2. Description of the Related Art Conventionally, there has been known an electric wire with a terminal fitting formed by electrically connecting a core wire exposed from an electric wire and a terminal fitting by ultrasonic welding.

  For example, in Patent Document 1, a twisted wire conductor (core wire) obtained by twisting aluminum strands is set in a terminal connection portion, and ultrasonic vibration is applied through the terminal while applying pressure, thereby joining the wire and the terminal. Techniques to do this are disclosed.

  In such ultrasonic welding of electric wires, the oxide film on the surface of the strands is destroyed by ultrasonic waves, and the exposed new surfaces are brought close to each other by the applied pressure from the outside. -The contact area of the terminals is enlarged and joined together. Therefore, in order to obtain a good bonding state, it is indispensable to press the wire to a certain level or more.

  However, the following problems arise when the size of the electric wire is increased and the number of strands is increased. That is, among the plurality of strands (core wires) set in the terminal, the strand located on the ultrasonic horn side is crushed so as to sink by pressurization from the horn, and the strand located on the terminal side Since it is greatly stretched in comparison, it leads to disconnection. Alternatively, when welding a thick wire, considering the fact that the ultrasonic energy emitted from the horn is attenuated in the wire, increase the amplitude, pressure, and time, which are energy factors, and position it on the terminal side. It is necessary to allow sufficient energy to reach the strands to be used, but on the other hand, the tension applied to the strands located on the horn side and the amount of heat generated by friction become too large, which may cause disconnection. .

  Furthermore, when a thick electric wire is crushed by pressurization from a horn, it spreads widely to the side, which increases the overall size.

JP 2003-86259 A

  The present invention has been completed based on the above-described circumstances, and is capable of preventing disconnection of a wire and making a good connection between an electric wire and a terminal and a small electric wire with a terminal fitting and an electric wire with a terminal fitting. It aims at providing the manufacturing method of.

  The present invention made in order to solve the above-mentioned problems has a terminal fitting comprising: an electric wire including a core wire composed of a plurality of strands; and a terminal fitting connected to the core wire exposed from the end of the electric wire. The terminal fitting is provided with a welded portion ultrasonically welded to the core wire, and the welded portion extends from the end of the core wire along the direction in which the wire extends. It is characterized in that it is inserted near the center in the radial direction.

  According to the present invention, since the welded portion of the terminal fitting is inserted near the center in the radial direction along the direction in which the electric wire extends, the core wire pressed from one direction toward the welded portion is the welded portion of the core wire. Compared to the case of being arranged at the end in the radial direction, it is about half. Therefore, even if the electric wire has a large diameter, the strand located near the outer periphery of the core wire is not greatly stretched during pressurization, and the strand breakage can be prevented.

  Moreover, when a welding part consists of a rectangular plate-shaped member, a core wire and a terminal metal fitting can be connected using both surfaces of a welding part. That is, when trying to secure a connection area equivalent to the configuration in which the core wire is connected to one side of the terminal as in the conventional case, it is only necessary to insert a welded portion having a half area of the conventional one into the core wire (equivalent to using both sides) From the area, the entire electric wire with terminal fittings can be reduced in size.

  In addition, when the core wire and the welded part of the terminal fitting are ultrasonically welded by pressing the horn against the core wire and applying ultrasonic vibration, the core wire between the horn and the welded part is formed on the surface of the strand. The formed oxide film is broken and the strands are welded together. At this time, the core wire located between the horn and the welded portion is about half of the case where the welded portion is disposed at the end portion in the radial direction of the core wire, so the core wire located near the horn is excessive. In addition, the energy output from the horn can be transmitted to the welded part without significantly reducing the energy, so that excessive energy is not applied to the core wire located near the horn, preventing disconnection. Is done.

  As described above, according to the present invention, it is possible to obtain a small electric wire with a terminal fitting in which a broken wire is prevented and the electric wire and the terminal fitting are in a good connection state.

The exploded perspective view before the assembly of the electric wire with a terminal metal fitting of one embodiment of the present invention Similarly, an exploded plan view before assembling the electric wire with terminal fittings Similarly, a plan view with the terminal welds inserted into the core wire Schematic of the state where the core wire with the welding part inserted is also placed on the anvil Similarly, conceptual diagram when applying ultrasonic vibration while applying pressure from one side with a horn Similarly, a conceptual diagram when applying ultrasonic vibration while applying pressure from the other side with a horn Similarly, plan view of electric wire with terminal fittings

An embodiment of the present invention will be described with reference to FIGS.
The electric wire 10 with a terminal metal fitting of this embodiment is wired between apparatuses (not shown), such as a battery, an inverter, and a motor, which constitute a power source for traveling in an electric vehicle, for example.

  FIG. 1 is an exploded perspective view of an electric wire 10 with terminal fittings according to this embodiment. As shown in the drawing, an electric wire 11 is made of a synthetic resin covering a core wire 12 made of a plurality of metal strands and an outer periphery of the core wire 12. The insulation coating 13 is provided. The core wire 12 can use arbitrary metals as needed, such as aluminum, an aluminum alloy, copper, a copper alloy. In this embodiment, aluminum or an aluminum alloy is used.

  On the other hand, the terminal fitting 20 is made of a metal plate material such as copper or copper alloy, and as shown in FIG. 1, a welded portion 21 made of a rectangular plate-like member inserted into the core wire 12 exposed on the end side of the electric wire 11. And a flat plate-like connecting portion 24 that is substantially annular and has a mounting hole 23 through which a mounting bolt (not shown) that extends to the welded portion 21 and has a thread formed on the outer peripheral surface is opened. It consists of. As shown in FIG. 2, the width | variety of the edge part side connected with the welding part 21 among the plate-shaped connection parts 24 is wider than the width | variety of the welding part 21, and the step part 25 by these width differences. Is forming.

  Next, the manufacturing method of the electric wire 10 with a terminal metal fitting of this embodiment is demonstrated. First, the insulating coating 13 at the end of the electric wire 11 is peeled off, and the welded portion 21 of the terminal fitting 20 is inserted along the length direction of the electric wire 11 from the exposed end of the core wire 12. At this time, the insertion position of the welded portion 21 with respect to the core wire 12 is the substantially central portion in the radial direction of the core wire 12 and the insertion depth is inserted until the step portion 25 abuts against the tip of the core wire 12 ( (See FIG. 3).

  Next, as shown in FIG. 4, the core wire 12 into which the welded portion 21 is inserted is placed on the anvil 30 of the ultrasonic device in a direction in which the plate surface of the welded portion 21 is horizontal. And the ultrasonic horn 31 distribute | arranged above the core wire 12 is dropped, and it pressurizes so that the core wire 12 may be crushed lightly (refer FIG. 5). Then, ultrasonic vibration is applied to the core wire 12.

  Then, the ultrasonic vibration emitted from the ultrasonic horn 31 is transmitted through the core wire 12 and reaches the welded portion 21. Along with transmission of ultrasonic vibration under such pressure, the strands of the core wire 12 are welded together, and the core wire 12 and the welded portion 21 are welded. At this time, the energy output from the ultrasonic horn 31 is such that the core wire 12 sandwiched between the ultrasonic horn 31 and the welded portion 21 and the energy at which the core wire 12 and the welded portion 21 are reliably welded. To do.

  Next, the core wire 12 is turned up and down, placed again on the anvil 30, and ultrasonic vibration is applied while pressing the ultrasonic horn 31 (see FIG. 6). Thereby, the core wires 12 between the ultrasonic horn 31 and the welded portion 21 and the core wire 12 and the welded portion 21 are welded to each other. Thereby, the electric wire 10 with a terminal metal fitting is completed (refer FIG. 7).

  According to the present embodiment, since the welded portion 21 of the terminal fitting 20 is inserted near the center of the radial direction along the direction in which the electric wire 11 extends, the core wire 12 pressed from one direction toward the welded portion 21 is Compared with the case where the welded portion 21 is disposed at the end portion in the radial direction of the core wire 12, it is about a half. Therefore, even if it is an electric wire with a large diameter, the strand located in the vicinity of the outer periphery of the core wire 12 is not largely extended at the time of pressurization, and a strand break can be prevented.

  Moreover, according to this embodiment, the welding part 21 consists of a rectangular plate-shaped member. In this case, the core wire and the terminal fitting 20 can be connected using both surfaces of the welded portion 21. That is, when it is intended to secure a connection area equivalent to the configuration in which the core wire is connected to one surface side of the terminal fitting as in the past, it is only necessary to insert the welding portion 21 having a half area of the conventional one into the core wire (use of both sides) Thus, the entire electric wire 10 with terminal fittings can be reduced in size.

  Moreover, when ultrasonic welding is performed between the core wire 12 and the welded portion 21 of the terminal fitting 20 by pressing the ultrasonic horn 31 against the core wire and applying ultrasonic vibration, the space between the ultrasonic horn 31 and the welded portion 21 is reduced. In the core wire 12, the oxide film formed on the surface of the strand is broken, and the strands are welded to each other. At this time, since the core wire 12 positioned between the ultrasonic horn 31 and the welded portion 21 is about half as compared with the case where the welded portion 21 is arranged at the radial end of the core wire 12, the horn Since the core wire 12 located near the horn is not excessively stretched, the energy output from the ultrasonic horn 31 can be transmitted to the welded portion 21 without being greatly attenuated. Excessive energy is not applied and disconnection is prevented.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  (1) In the above embodiment, the welded portion 21 is a rectangular plate-shaped member. However, the present invention is not limited to this, and may be a rod-shaped member such as a round bar or a square bar, and is inserted near the center of the core wire in the radial direction. Any form is possible as long as it is possible.

  (2) The material and form of the terminal fitting and core wire are not limited to the above embodiment. As a terminal metal fitting, arbitrary terminal metal fittings can be used as needed, such as a male terminal metal fitting, a female terminal metal fitting, and a splice terminal, for example.

  (3) It is good also as the shape gradually changed from the terminal connection part 24 to the welding part 21, without providing the step part 25 in the terminal metal fitting 20. FIG.

DESCRIPTION OF SYMBOLS 10 ... Electric wire with terminal metal fitting ... Electric wire 12 ... Core wire 13 ... Insulation coating 20 ... Terminal metal fitting 21 ... Welding part 24 ... Terminal connection part 25 ... Step part

Claims (6)

An electric wire with a terminal fitting comprising: an electric wire including a core wire composed of a plurality of strands; and a terminal fitting connected to the core wire exposed from an end of the electric wire,
The terminal fitting is provided with a welded portion ultrasonically welded to the core wire, and the welded portion extends from the end side of the core wire in the radial direction of the wire along the direction in which the wire extends. An electric wire with terminal fittings, characterized by being inserted in the vicinity. 2. The electric wire with terminal fitting according to claim 1, wherein the welded portion is formed of a rectangular plate-like member, and the core wire is welded to both surfaces of the welded portion. The electric wire with a terminal fitting according to claim 1 or 2, wherein the element wire is made of aluminum, an aluminum alloy, copper, or a copper alloy. A method of manufacturing an electric wire with a terminal fitting, comprising: an electric wire formed by insulatingly covering a core wire composed of a plurality of strands; and a terminal fitting ultrasonically welded to the core wire exposed from an end of the electric wire. ,
Peeling the insulation coating covering the outer peripheral surface of the core wire to expose the core wire;
Inserting the welded portion of the terminal fitting in the vicinity of the exposed radial center of the core wire along the direction in which the electric wire extends from the end side of the core wire; and
And a step of applying pressure while applying ultrasonic vibration to the core wire into which the welded portion is inserted. The welded portion is formed of a rectangular plate-like member, and in the step of applying pressure while applying ultrasonic vibration to the core wire into which the welded portion is inserted, the welded portion is perpendicular to the plate surface of the welded portion from one side. 5. The electric wire with terminal fitting according to claim 4, wherein after applying pressure while applying ultrasonic vibration, the pressure is applied while applying ultrasonic vibration in a direction perpendicular to the plate surface of the welded portion from the other side. Production method. The said strand is a manufacturing method of the electric wire with a terminal metal fitting of Claim 4 or Claim 5 which consists of aluminum, an aluminum alloy, copper, or a copper alloy.

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