JP4158889B2 - Terminal structure with terminal and terminal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a terminal-attached electric wire terminal structure and a terminal used for automobile wiring and the like.
[0002]
[Prior art]
Conventionally, an electric wire terminal structure with a terminal in which a terminal of an electric wire is connected to a terminal is used for wiring in an automobile or the like. As a terminal constituting the wire terminal structure, a press contact terminal 1 as shown in FIG. 5A is frequently used (for example, see Patent Document 1). The press contact terminal 1 is formed by pressing a single metal thin plate, and is electrically connected to the terminal of the mating connector to be electrically connected, and an electric wire formed on the rear side thereof. The left and right side walls 5, 5 are provided with a connecting portion 3, and are erected so as to have a U-shaped cross section with a curved bottom wall 4 projecting downward and curved bottom walls 4 on both sides thereof. And a pair of press contact blades 6, 6 formed by cutting and raising a part of both side walls 5, 5 and the press contact blades 6, 6, and an electric wire 7 (see FIG. 5) between the press contact blades 6, 6. When the terminal of (b) is press-fitted, the press contact blades 6 and 6 are brought into contact with the conductor 7a of the stranded wire by breaking the coating 7b, so that the press contact slit 8 electrically connects the conductors 7a to each other. It is configured. In addition, 9 is the electric wire crimping part which is formed in the back side of the electric wire connection part 3, and grips the electric wire 7, It is a U-shaped cross section with the curved bottom wall 4 convex downward, and the curved bottom wall 4 on the both sides. The left and right presser pieces 10 and 10 are erected so as to be.
[0003]
When the terminal of the electric wire 7 is connected to the press contact terminal 1, the terminal of the electric wire 7 is positioned immediately above the electric wire connecting portion 3 and the electric wire crimping portion 9 of the terminal 1, as shown in FIG. Next, the end of the electric wire 7 is press-fitted into the press-contacting slit 8 of the electric wire connecting portion 3 from above. As a result, the sheath 7b of the electric wire 7 is broken by the press contact blades 6 and 6 and brought into contact with the conductor 7a, and the conductors are sandwiched by the press contact blades 6 and 6 to electrically connect the press contact blades 6 and 6 and the conductor 7a. On the other hand, the end of the electric wire 7 is press-fitted from above into the press-contact slit 8 of the electric wire connecting portion 3, and at the same time, the end of the electric wire 7 is inserted into a U-shaped recess between the holding pieces 10 and 10 of the electric wire crimping portion 9. Next, as shown in FIG. 6, the upper ends of the presser pieces 10 and 10 are bent inward to clamp and hold the electric wire 7. In this manner, a terminal-attached electric wire terminal structure as shown in FIG. 6 is formed.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-50357 (Description of paragraphs 0025 to 0034, 0038 and FIG. 1)
[0005]
[Problems to be solved by the invention]
According to the terminal-attached electric wire terminal structure having such a configuration, a portion of the conductor 7a of the electric wire 7, that is, two portions on the outer peripheral surface side are provided on the press contact blades 6, 6 of the electric wire connecting portion 3 constituting the terminal 1. The press contact blades 6 and 6 and the conductor 7a are electrically connected to each other, but the conductor 7a is formed by twisting copper wires that have a relatively small electric resistance and are difficult to form an oxide film on the surface. The electrical resistance between the copper wires does not increase, and current flows only through some of the wires including the vicinity of the press contact blades 6 and 6 to generate concentrated resistance. Less is. Moreover, the copper strand has a relatively high fusing temperature. Therefore, the electric wire 7 connected to the terminal is less likely to generate heat during operation and melt and cause poor conduction.
[0006]
However, in recent years, in order to reduce energy consumption as part of global environmental protection, there has been an active movement to reduce the weight of transport equipment such as automobiles. It has been studied to form the conductors of the terminal 1 and the electric wire 7 with an aluminum material. Then, the conductor 7 has a higher electrical resistance than the copper material, and is formed by twisting aluminum strands on which the oxide film is easily formed. The electrical resistance between these strands is increased, and the press contact blade 6 and 6, current concentrates and flows only in some of the strands that contact or include the vicinity thereof, and it is easy to generate concentrated resistance. Also, the aluminum wire has a lower fusing temperature than the copper wire. For this reason, the electric wire 7 connected to the terminal 1 is likely to generate heat and melt while being energized, which may cause poor conduction, and there is a problem of reducing the quality and reliability of the terminal-attached electric wire terminal structure.
[0007]
In order to solve such a problem, it is also conceivable to form a terminal-attached electric wire terminal structure by joining and connecting the terminal of the electric wire 7 to the terminal 1 by resistance welding. However, in the structure of the terminal 1, there is no smooth surface necessary for resistance welding, and it is easy to efficiently generate heat at a temperature necessary for resistance welding (joining) the contact surface between the terminal 1 and the electric wire 7. In addition, there is a problem that a terminal-attached electric wire terminal structure that maintains a good conduction state cannot be formed.
[0008]
The present invention solves the above-mentioned problems, and the terminal and the conductor of the electric wire are made of aluminum material, and the terminal conductor of the electric wire is connected to the terminal with high resistance welding strength and maintaining a good conduction state. It aims at providing the electric wire terminal structure with a terminal which can do, and a terminal.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the terminal-attached electric wire terminal structure according to claim 1 of the present invention is a terminal-attached electric wire terminal structure formed by connecting an end of an electric wire to a terminal provided with an electric wire connecting portion having a bottom wall. The conductor of the electric wire is made of a plurality of strands of aluminum or aluminum alloy wires, the terminal is made of aluminum or an aluminum alloy, and the electric wire connecting portion of the terminal has a bottom wall formed on a smooth surface, A convex portion formed of a ridge on the smooth surface is provided to be inclined with respect to the longitudinal axis of the electric wire to be connected, and the convex portion is configured to be directly connected to the conductor of the end of the electric wire by resistance welding , The conductor is prevented from fusing when an oxide film is formed on the conductor surface of the strand .
[0010]
According to such a configuration, since the bottom wall of the electric wire connection portion in the terminal is formed on a smooth surface, the conductor of the end of the electric wire is connected to the smooth surface by resistance welding (bonding) with a large bonding strength. Can do. In addition, since the convex portion protrudes from the smooth surface, when resistance welding the conductor of the end of the electric wire to the smooth surface, the electrical resistance of the contact surface between the smooth surface of the bottom wall and the conductor increases. Concentrated resistance is likely to occur on the contact surface, and the heat generated in that part is quickly transmitted to the entire conductor, the entire conductor is efficiently heated, and the conductor is reliably resistance welded to the bottom wall of the wire connection part. Is done. In particular, when the convex portion formed of a ridge is inclined and protruded with respect to the longitudinal axis of the electric wire to be connected, the convex portion is protruded in a direction perpendicular to the longitudinal axis of the electric wire to be connected. The terminal is less likely to be bent at the portion of the electric wire connection than the one, the terminal strength (rigidity) is increased, and the protruding portion is protruded in a direction parallel to the longitudinal axis of the electric wire. The contact electrical resistance increases, the electric wire can be efficiently heated, and the electric wire can be resistance-welded to the terminal more securely and mechanically and electrically connected. As a result, when the terminals are formed of an aluminum material and the conductor is formed by twisting aluminum wires on which the oxide film is easily formed on the surface, the current flows between these wires almost evenly, and the conductor is blown out. It is possible to reduce conduction failure. Furthermore, since it becomes possible to connect the conductor of the terminal of an electric wire to a terminal, maintaining a favorable conduction | electrical_connection state, the quality and reliability of the electric wire terminal structure with a terminal can be improved.
[0011]
The terminal-attached electric wire terminal structure according to claim 2 of the present invention is the one according to claim 1, characterized in that the convex portions made of the convex strips are in contact with the conductor at a plurality of locations. Is.
[0012]
[0013]
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows one embodiment of a terminal constituting a terminal-attached electric wire terminal structure according to the present invention, wherein (a) is a front view and (b) is a plan view.
[0015]
The terminal 20 is formed by pressing a thin plate obtained by molding a single aluminum (including aluminum alloy) material, and is electrically connected by fitting contact with a terminal of a mating connector. The electric contact part 22 and the electric wire connection part 24 formed in the back side are provided. The electric wire connecting portion 24 includes a bottom wall 26 formed on a smooth surface, left and right side walls 28 and 28 erected so as to have a U-shaped cross section with the bottom wall 26 opening at both sides thereof, The flat surface of the bottom wall 26 between the walls 28 and 28 is inclined at an angle of 45 degrees, for example, with respect to the longitudinal axis of the electric wire 30 to be connected to the terminal 20 as shown in FIG. Further, it is formed by a projecting portion (indent) 32 made up of a plurality of projecting strips that project from the upper side, that is, toward the wire 30 side by pressing or the like, and come into contact with the conductor 30a of the wire 30.
[0016]
As shown in the drawing, it is preferable that the side walls 28 are erected because the terminal 20 can be prevented from being bent at the portion of the electric wire connecting portion 24 and the terminal strength can be increased. Further, as shown in the figure, when the heights of the side walls 28, 28 are the same as the height of the convex portion 32, and the height positions of the side walls 28, 28 and the convex portion 32 are aligned, This is preferable because it does not hinder resistance welding of the end of the electric wire 30 to the bottom wall 26 in the electric wire connecting portion 24 and the welding workability is improved.
[0017]
The convex portion 32 may protrude in a direction orthogonal to the longitudinal axis of the electric wire 30 (direction of 90 degrees), or may protrude in a direction parallel to the longitudinal axis of the electric wire 30. As shown in (b), when the projection is inclined with respect to the longitudinal axis of the electric wire 30, the terminal 20 is connected to the electric wire rather than the one projecting in a direction perpendicular to the longitudinal axis of the electric wire 30. part 2 hardly bent at 4 sites, terminal strength (rigidity) increases. Moreover, the contact electrical resistance with the electric wire 30 becomes larger than that projecting in a direction parallel to the longitudinal axis of the electric wire 30, and the electric wire 30 can be efficiently heated. Therefore, it is preferable because the electric wire can be resistance-welded more securely to the terminal and mechanically and electrically connected, and the quality and reliability of the terminal-attached electric wire terminal structure can be further improved.
[0018]
Moreover, in the thing of the said structure, although the several convex part 32 is protrudingly provided, you may make it the single protruding part 32 protrude. Moreover, you may form so that the convex part 32 of 1 item | stripes or multiple items | stripes may arrange | position many protrusions intermittently in a length direction, and may become the protruding item | line body which continues entirely.
[0019]
Incidentally, 34 is formed on the rear side of the wire connecting portion 24 and is a wire crimping portion for gripping the electric wire 30. The bottom wall 26 formed on the smooth surface and both sides of the bottom wall 26 are upwardly spread slightly outward. The left and right presser pieces 36 and 36 are provided so as to be inclined.
[0020]
Next, a method of connecting the terminal of the electric wire 30 to the terminal 20 to form the terminal-attached electric wire terminal structure according to the present invention will be described with reference to FIG. 2. The terminal of the electric wire 30 to be connected to the terminal 20 in advance. The coating 30b is peeled off for a predetermined length to expose the conductor 30a. The conductor 30a is formed by twisting a plurality of aluminum (including aluminum alloy) strands.
[0021]
Next, the end of the electric wire 30 subjected to the terminal treatment in this way, the protruding portion 32 in which the exposed portion of the conductor 30a protrudes from the smooth surface of the bottom wall 26 in the electric wire connecting portion 24 of the terminal 20; Further, the portion of the electric wire 30 that is covered with the coating 30 b is inserted into the concave portion between the presser pieces 36, 36 of the electric wire crimping portion 34, and is placed so as to contact the bottom wall 26.
[0022]
Next, in the wire connection part 24 of the terminal 20, resistance welding is performed between the lower part of the bottom wall 26 where the exposed part of the conductor 30a is placed and the upper part of the exposed part of the conductor 30a. It is sandwiched between the lower electrode 38 and the upper electrode 40 of the machine, pressurizes the bottom wall 26 of the terminal 20 and the conductor 30a of the electric wire 30 with hydraulic pressure or other pressurizing means, and between the electrodes 38, 40. A large welding current (direct current) is supplied to the power source 42 to cause the contact surface between the bottom wall 26 and the conductor 30a to reach the welding temperature by the heat generated by the resistance and weld (join).
[0023]
At this time, since the convex portion 32 protrudes from the smooth surface of the bottom wall 26, the electrical resistance of the contact surface between the smooth surface of the bottom wall 26 and the conductor 30a increases, and concentrated resistance is generated on the contact surface. The heat generated in that portion is quickly transmitted to the entire conductor 30a, the entire conductor 30a generates heat efficiently, and the conductor 30a is reliably resistance welded and connected to the bottom wall 26 of the wire connection portion 24. . Thereby, in the case where the terminal 20 is formed of an aluminum material and the conductor 30a is formed by twisting aluminum strands on which an oxide film is easily formed, the current flows between these strands almost evenly, It is possible to reduce conduction failures due to the melting of the conductor 30a.
[0024]
In this manner, after the conductor 30a of the end of the electric wire 30 is connected to the smooth surface of the bottom wall 26 of the electric wire connecting portion 24 of the terminal 20 by resistance welding, the upper ends of the presser pieces 36 , 36 of the electric wire crimping portion 34 are connected. The cover 30b of the electric wire 30 is tightened and gripped by bending the portion inward.
[0025]
In addition, before connecting the conductor 30a at the end of the electric wire 30 to the bottom wall 26 of the terminal 20, the covering 30b of the electric wire 30 may be fastened and fixed by the electric wire crimping portion 34. This is preferable because when the electric wire 30 is resistance-welded to the terminal 20, the conductor 30 a can be reliably welded without causing positional displacement of the conductor 30 a.
[0026]
In this way, a terminal-attached electric wire terminal structure as shown in FIGS. 3A and 3B is formed. According to such an electric wire terminal structure, since it becomes possible to connect the conductor 30a of the terminal of the electric wire 30 to the terminal 20 while maintaining a good conduction state, the quality and reliability of the electric terminal structure with terminal are improved. be able to.
[0027]
In the embodiment, the convex portion 32 made of a single or a plurality of convex strips protrudes from the smooth surface of the bottom wall 26 in the electric wire connecting portion 24. Instead of the convex portion 32, FIG. Such a smooth surface of the bottom wall 26 may be provided with a protruding portion 44 in which a large number of protrusions 44 a protruding upward (on the electric wire 30 side) are randomly arranged. The same effect as that of the convex portion 32 can be obtained by the convex portion 44 protruding in this way.
[0028]
【The invention's effect】
As described above, the terminal-equipped wire terminal structure according to claim 1 of the present invention is a made by connecting the end of a wire to a terminal having a wire connecting portion having a bottom wall, a conductor of the electric wire Is made of stranded wires of a plurality of aluminum or aluminum alloy wires, the terminal is made of aluminum or an aluminum alloy, and the electric wire connection portion of the terminal has a bottom wall formed on a smooth surface, and a convex line on the smooth surface. A convex portion made of a body is provided to be inclined with respect to the longitudinal axis of the electric wire to be connected, and the convex portion is configured to be directly connected to the conductor of the end of the electric wire by resistance welding, and the conductor surface of the element wire Since the fusing of the conductor is prevented when an oxide film is formed on the wire, the conductor of the end of the electric wire is efficiently resistance-welded with a large bonding strength to the bottom wall of the terminal and mechanically and electrically connected. Can do. Moreover, even if the conductor of a terminal and an electric wire is formed with the aluminum material, the conduction | electrical_connection defect by melting of a conductor can be reduced. Furthermore, since it becomes possible to connect the conductor of the terminal of an electric wire to a terminal, maintaining a favorable conduction | electrical_connection state, the quality and reliability of the electric wire terminal structure with a terminal can be improved .
[Brief description of the drawings]
FIG. 1 shows an embodiment of a terminal constituting a terminal structure with terminal according to the present invention, in which (a) is a front view, (b) is a plan view, and (c) is an X- It is X arrow sectional drawing.
FIG. 2 is a schematic diagram showing a method of connecting a conductor of an electric wire to the terminal of FIG. 1 by resistance welding.
FIGS. 3A and 3B show an embodiment of a terminal-attached electric wire terminal structure according to the present invention, wherein FIG. 3A is a front view and FIG. 3B is a plan view.
4 is a plan view showing a modified example of a convex portion projecting from the bottom wall of the terminal of FIG. 1; FIG.
5A and 5B show a pressure contact terminal constituting a conventional terminal-attached electric wire terminal structure, in which FIG. 5A is a perspective view, and FIG. 5B is a cross-sectional view showing a YY arrow portion of FIG. .
6 is a perspective view showing a conventional terminal-attached electric wire terminal structure formed by connecting a terminal of an electric wire to the press contact terminal of FIG. 5. FIG.
[Explanation of symbols]
20 Terminal 22 Electrical contact part 24 Electric wire connection part 26 Bottom wall 28 Side wall 30 Electric wire 32 Convex part 34 Electric wire crimping part 36 Pressing piece 38 Electrode 40 Electrode 42 Power supply 44 Convex part 44a Protrusion

Claims (2)

In a terminal structure with a terminal formed by connecting a terminal of an electric wire to a terminal having a wire connecting portion having a bottom wall, the conductor of the electric wire is composed of a plurality of aluminum or aluminum alloy strands, and the terminal is The wire connecting portion of the terminal is made of aluminum or an aluminum alloy, and the bottom wall of the wire connecting portion is formed on a smooth surface, and the protruding portion made of a ridge on the smooth surface is inclined with respect to the longitudinal axis of the wire to be connected. The protrusion is configured to be directly connected to the conductor of the end of the electric wire by resistance welding, and the conductor is prevented from being melted when an oxide film is formed on the conductor surface of the element wire. Characteristic terminal structure with terminal. 2. The terminal-attached electric wire terminal structure according to claim 1 , wherein the convex portion formed of the convex body is in contact with a plurality of locations separated from the conductor .

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