WO2017195756A1 - Terminal and terminal-equipped electrical wire - Google Patents

Abstract

This terminal (30) is to be crimped onto an end portion of a covered electrical wire (20) comprising a core wire (21) covered by an insulation cover (22). This terminal (30) comprises: a wire barrel (33) to be crimped onto the core wire (21) exposed at the end portion of the covered electrical wire (20); a terminal connection portion (31) to be connected to a counterpart terminal and having a square tube portion (31B) on at least a rear end side; and a grooved linking portion (32) placed in such a manner as to link the wire barrel (33) to the square tube portion (31B) of the terminal connection portion (31), and having a bottom surface (32A) that is continuous and flush with the bottom surface (31A) of the square tube portion (31B). In addition, at the bottom surface (32A) of the grooved linking portion (32), a water guide groove (40) is formed as a depression in a shape where the forward end thereof extends into the bottom surface (31A) of the square tube portion (31B).

Description

Terminal and electric wire with terminal

The technique disclosed by this specification is related with a terminal and an electric wire with a terminal.

For example, when an aluminum wire is conductively connected to a terminal, when the core wire of the aluminum wire and the terminal are formed of different kinds of metals, especially when moisture is present at the contact portion between the two wires, both metals are converted into ions in the moisture. It is known that electrolytic corrosion occurs in which corrosion of the base metal proceeds due to the electrochemical reaction due to melting.
Therefore, conventionally, as described in Patent Document 1 below, electrolytic corrosion is prevented by sealing an electric wire connecting portion (barrel) in a terminal with an anticorrosive agent made of a resin mold or the like.

JP 2003-297447 A

However, the anti-corrosion measures using anti-corrosion agents require a separate process and corresponding equipment for adhering the anti-corrosion agents, which may lead to an increase in manufacturing costs. It had been.
The technology disclosed in this specification has been completed based on the above situation.

The terminal disclosed in this specification is a terminal that is crimped to a terminal portion of a covered electric wire whose core wire is covered with an insulating coating, and is a wire barrel that is crimped to the core wire exposed at the terminal portion of the coated electric wire. A terminal connecting portion connected to the mating terminal and having a square tube portion at least on the rear end side, the square tube portion of the terminal connection portion and the wire barrel being connected to each other, and a bottom surface of the square tube portion; A groove-shaped connecting portion having a bottom surface that is flush with the same surface, and a water guide groove is formed on the bottom surface of the groove-shaped connecting portion with a tip extending to the bottom surface of the rectangular tube portion. It is the structure which is done.

When water drops on the groove-shaped connecting part, water is collected in the water guide groove formed on the bottom surface, and then flows down toward the tip of the water guide groove along the water guide groove due to the capillary phenomenon of the rectangular tube part, that is, terminal connection It is retracted to the rear end side of the part, and it is avoided that a water pool is formed in the groove-shaped connecting part. For this reason, even if the core wire and the terminal of the covered electric wire are made of different metals, moisture does not intervene in the portion where the core wire and the groove side connecting portion are in contact with each other, and as a result, the occurrence of electrolytic corrosion is prevented. .
Since it can be handled only by adding processing to the terminal, it can be realized at a lower cost than the case of using an anticorrosive agent.

The following configuration may also be used.
The water guide groove is formed in a tapered shape that becomes gradually narrower toward the tip.
The water collecting ability at the bottom of the groove-shaped connecting portion is excellent, and the capillarity of the water guiding groove itself functions effectively, thereby improving the ability to retract water.

An escape hole penetrating the outer surface is formed at the tip of the water guide groove.
The water flowing down along the water guide groove is released to the outside of the terminal from the escape hole at the tip. It is possible to more reliably prevent water accumulation at the groove-shaped connecting portion.

The electric wire with a terminal disclosed by this specification is the structure by which the terminal as described above was crimped | bonded to the terminal part of the covered electric wire by which the core wire was covered with the insulation coating.
Here, the core wire may be made of aluminum or an aluminum alloy, and the terminal may be made of copper or a copper alloy.

According to the technology disclosed in the present specification, it is possible to realize electric corrosion prevention at a low cost.

The partially cutaway top view of the electric wire with a terminal concerning Embodiment 1 Partial cutaway side view of electric wire with terminal Partially cutaway plan view of the electric wire with terminal according to the second embodiment Partially cutaway plan view of the electric wire with terminal according to the third embodiment Partial cutaway side view of electric wire with terminal

<Embodiment 1>
Embodiment 1 is demonstrated based on FIG.1 and FIG.2. The electric wire with terminal 10 according to the first embodiment is configured such that a female terminal 30 is conductively connected to the end of an aluminum electric wire 20. The female terminal 30 is fitted and connected to a male terminal (not shown).

The aluminum electric wire 20 is a covered electric wire and has a structure in which the outer periphery of a core wire 21 in which a plurality of metal strands 21A made of aluminum or aluminum alloy are bundled is covered with an insulating coating 22 made of synthetic resin.
In connecting the female terminal 30 to the aluminum electric wire 20, the terminal of the aluminum electric wire 20 is subjected to a terminal process in which the terminal of the insulating coating 22 is cut (skinned) for a predetermined length to expose the core wire 21. .

The female terminal 30 is formed by pressing a copper or copper alloy base material. The female terminal 30 is provided with a terminal connecting portion 31, a groove-shaped connecting portion 32, a wire barrel 33, and an insulation barrel 34 that are connected to the male terminal (mating terminal) of the counterpart in order from the front side.
The terminal connection portion 31 is formed in a generally rectangular tube shape, and is provided with an elastic contact piece (not shown) inside. By inserting a tab of a male terminal into the terminal connection portion 31, electrical connection is achieved. It is like that. The rear end portion of the terminal connection portion 31 corresponds to the rectangular tube portion 31B.

The groove-shaped connecting portion 32 functions to connect the rear end of the terminal connecting portion 31 and the wire barrel 33, and the side plate extends from both side edges of the bottom plate 32 A that is flush with the bottom plate 31 A of the terminal connecting portion 31. 32B is formed in a raised groove shape.

The wire barrel 33 functions to crimp the exposed core wire 21 of the aluminum electric wire 20, and is initially a pair of wide and low-profile from both side edges of the bottom plate 33 </ b> A connected to the bottom plate 32 </ b> A of the groove-shaped connecting portion 32. The barrel piece 33B is formed in a raised shape.

The insulation barrel 34 is arranged behind the wire barrel 33 with a predetermined interval. The insulation barrel 34 functions to crimp the end of the insulation coating 22 remaining after the skinning process in the aluminum electric wire 20, and initially, from both side edges of the bottom plate 34 </ b> A connected to the bottom plate 33 </ b> A of the wire barrel 33, A pair of narrow and tall barrel pieces 34B is formed in a raised shape.

Now, in the female terminal 30 described above, at the center width position of the bottom plate 32A of the groove-shaped connecting portion 32, a water guide groove 40 that is elongated in the front-rear direction, and its tip is the rear end portion (square tube portion 31B) of the terminal connecting portion 31. A recess is formed in a form extending a predetermined dimension toward the bottom plate 31A.

Subsequently, the operation and effect of this embodiment will be described. In connecting the terminal of the aluminum electric wire 20 to the female terminal 30, a crimping jig composed of an anvil and a crimper is used. Specifically, after the bottom plate 33A, 34A from the wire barrel 33 to the insulation barrel 34 in the female terminal 30 is set on the anvil, the aluminum wire 20 is subjected to the terminal treatment as described above. The exposed core wire 21 is placed on the bottom plate 33A of the wire barrel 33, and the end of the insulating coating 22 is placed on the bottom plate 34A of the insulation barrel 34, respectively.

<The crimper is lowered from this state, so that the wire barrel 33 and the insulation barrel 34 are caulked. For example, in the wire barrel 33, the left and right barrel pieces 33 </ b> B are crimped in a curved shape so as to embrace the core wire 21 while abutting the tips. The insulation barrel 34 is crimped so that the left and right barrel pieces 33 </ b> B are wrapped around the ends of the insulating coating 22 in a cylindrical shape while wrapping the tips.

By the above crimping operation, the terminal-attached electric wire 10 in which the female terminal 30 is connected to the end of the aluminum electric wire 20 is formed. The female terminal 30 of the terminal-attached electric wire 10 is accommodated in a female housing (not shown), and the female housing is fitted into the male housing in which the male terminal is accommodated, so that the male terminal corresponding to the female terminal 30 is obtained. Are fitted and connected.

Here, for some reason, when water hangs on the female housing and the female terminal 30 accommodated therein, and particularly when water drops and accumulates in the groove-shaped connecting portion 32 of the female terminal 30, the groove-shaped connecting portion 32 is made of a dissimilar metal. Since the core wire 21 in a certain aluminum electric wire 20 and the inner surface of the groove-shaped connecting portion 32 in the female terminal 30 are in contact with each other, there is a possibility that electrolytic corrosion occurs at the contact portion.

However, in this embodiment, since the water guide groove 40 is formed to be recessed from the bottom plate 32A of the groove-shaped connecting portion 32 to the bottom plate 31A of the rectangular tube portion 31B at the rear end portion of the terminal connecting portion 31, the groove-shaped connecting portion 32 is formed. When water is dripped, the water is collected in the water guide groove 40 formed in the bottom plate 32A, and then flows down toward the tip of the water guide groove 40 along the water guide groove 40 due to the capillary phenomenon of the rectangular tube portion 31B. Retreating to the rear end side of the connecting portion 31 avoids the formation of a water pool in the groove-shaped connecting portion 32. Therefore, moisture does not intervene in the portion where the core wire 21 of the aluminum wire 20 which is a dissimilar metal and the inner surface of the groove-shaped connecting portion 32 in the female terminal 30 are in contact with each other, and as a result, the occurrence of electrolytic corrosion is prevented. Is done.

In particular, the anti-corrosion measures of the present embodiment can be dealt with only by adding processing to the female terminal 30 such as forming the water guide groove 40 in the female terminal 30, so that an anti-corrosive that requires a separate process and apparatus is used. Compared with the case where it was, it becomes possible to implement | achieve cheaply.

<Embodiment 2>
A second embodiment will be described with reference to FIG. In the electric wire with terminal 10X according to the second embodiment, the shape of the water guide groove 42 formed in the female terminal 30X is changed. In the following, portions different from those in the first embodiment will be mainly described, and members and parts having the same functions as those in the first embodiment will be denoted by the same reference numerals, and description thereof will be omitted or simplified.

In this embodiment, there is a water guide groove 42 that is recessed from the bottom plate 32A of the groove-shaped connecting portion 32 in the female terminal 30X to the rear end portion of the bottom plate 31A of the rectangular tube portion 31B in the rear end portion of the terminal connection portion 31. The tapered shape gradually becomes narrower toward the tip. Specifically, the shape of the water guide groove 40 is a shape that allows water that has flowed into the base end side of the water guide groove 40 to flow down to the tip side by capillary action.

If the water guide groove 42 having such a shape is formed, the water collecting ability on the bottom plate 32A of the groove-shaped connecting portion 32 is excellent, and the capillary phenomenon of the water guide groove 42 itself functions effectively, so that water is connected to the terminal. The ability to retreat to the part 31 side can be improved. As a result, it becomes more effective as an anticorrosion measure.

<Embodiment 3>
A third embodiment will be described with reference to FIGS. 4 and 5. In the electric wire with terminal 10Y of the third embodiment, the water guide groove 44 formed in the female terminal 30Y is further improved.
The water guide groove 44 of the third embodiment has a tapered shape in which the planar shape is gradually narrowed toward the tip, similarly to the water guide groove 42 of the second embodiment, and the tip of the water guide groove 44. In addition, an escape hole 45 penetrating the lower surface of the bottom plate 31A of the terminal connection portion 31 (square tube portion 31B) is formed.

When the water guide groove 44 having such a shape is formed, the water flowing down along the water guide groove 44 is released from the escape hole 45 at the tip to the outside of the terminal connection portion 31 in the female terminal 30. Therefore, water accumulation at the groove-shaped connecting portion 32 is more reliably prevented, and it is further effective as a corrosion prevention measure.

<Other embodiments>
The technology disclosed in this specification is not limited to the embodiments described with reference to the above description and drawings, and includes the following embodiments, for example.
(1) The structure in which the escape hole is formed at the tip of the water guide groove can also be applied to a straight water guide groove as exemplified in the first embodiment.
(2) Although the female terminal is illustrated as a terminal in the said embodiment, it is applicable also to the male terminal which has the terminal connection part of the shape which made the tab protrude from the square cylinder-shaped main-body part.

(3) In the above embodiment, a covered electric wire having a core wire composed of a plurality of metal strands has been exemplified. For example, the core wire is formed of one metal strand having a relatively large diameter, that is, a single wire. A core-type covered electric wire may be used.
(4) In the said embodiment, although what connected the terminal made from copper or a copper alloy to the aluminum electric wire was illustrated as an electric wire with a terminal, not only this but the core wire of a covered electric wire and the terminal connected to this The present invention can be widely applied to all formed by different kinds of metals.

10, 10X, 10Y: Electric wire with terminal 20: Aluminum electric wire (covered electric wire)
21: Core wire 22: Insulation coating 30, 30X, 30Y: Female terminal (terminal)
31: Terminal connection part 31A: Bottom plate (bottom surface)
31B: Square tube portion 32: Groove-shaped connecting portion 32A: Bottom plate (bottom surface)
33: Wire barrel 40: Water guide groove 42: Water guide groove 44: Water guide groove 45: Relief hole

Claims (5)

1. A terminal whose core wire is crimped to the end of a covered electric wire covered with an insulation coating,
   A wire barrel that is crimped to the core wire exposed at the end of the coated wire;
   A terminal connecting portion connected to the mating terminal and having a square tube portion at least on the rear end side;
   A groove-shaped connecting portion that is arranged by connecting the rectangular tube portion of the terminal connecting portion and the wire barrel, and has a bottom surface that is flush with the bottom surface of the rectangular tube portion;
   And the terminal by which the water guide groove was dented in the form which the front-end | tip extended to the said bottom face of the said square cylinder part in the said bottom face of the said groove-shaped connection part.
2. The terminal according to claim 1, wherein the water guide groove is formed in a tapered shape that gradually becomes narrower toward the tip.
3. The terminal according to claim 1 or 2, wherein an escape hole penetrating the outer surface is formed at a tip of the water guide groove.
4. The electric wire with a terminal by which the terminal as described in any one of Claim 1 thru | or 3 was crimped | bonded to the terminal part of the covered electric wire by which the core wire was covered with the insulation coating.
5. The electric wire with a terminal according to claim 4, wherein the core wire is made of aluminum or an aluminum alloy, and the terminal is made of copper or a copper alloy.

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