JP2553219Y2 - Connecting terminal - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection terminal suitable as a joint for connecting a wire made of aluminum or an aluminum alloy, such as a high-voltage transmission line, to a substation facility.

[0002]

2. Description of the Related Art Hitherto, aluminum or aluminum alloy has been used for high-voltage power transmission lines used in high-rise buildings or the like in order to reduce the weight of electric wires. On the other hand, in a transformer that receives and transforms power supplied from such a high-voltage transmission line, copper is used for a conductor portion such as a bus bar. For this reason, when the electric wire made of aluminum or an aluminum alloy and the copper conductor portion of the transformer are directly connected, electric corrosion (hereinafter referred to as electrolytic corrosion) occurs at the connection portion due to a difference in energy level between the electric wires.

Therefore, various connection terminals have been proposed in which a copper plate or a copper plating layer is previously provided on the connection surface of the terminal body to prevent electrolytic corrosion.

FIG. 7 is a perspective view showing a conventional compression connection terminal. The terminal body 11 made of aluminum has a cubic shape, and a sleeve 12 is connected to one end in the longitudinal direction. The sleeve 12 has a cylindrical shape, and an electric wire is compression-fixed in the cylinder.
The electric wire and the terminal main body 11 are electrically connected to each other via the connection line 2. Then, the solder 1 is provided on the connection surface of the terminal body 11.
3, the copper plate 14 is joined.

FIG. 8 is a perspective view showing a conventional compression connection terminal disclosed in Japanese Utility Model Publication No. Sho 60-13178. In this terminal, a copper plating layer 15 is formed on the entire surface of a terminal body 11 made of aluminum instead of soldering a copper plate.

FIG. 9 is a perspective view showing a conventional compression connection terminal disclosed in Japanese Utility Model Publication No. 1-40128 and Japanese Utility Model Publication No. 2-3259. In this case, by performing a pretreatment on the terminal body 11, the underlayer 16 is formed only on the connection surface of the terminal body 11, and the copper plating layer 1 is formed on the surface of the underlayer 16.
7 are formed.

[0007] In FIGS. 7 to 9, the copper plate 14 is used.
A plurality of bolt holes are provided through the terminal body 11 from the surfaces of the copper plating layers 15 and 17, and a bolt is inserted into the bolt hole and the bolt is fixed, so that the compression connection terminal is fixed to a predetermined position. It can be connected to a member.

[0008]

However, the above-mentioned conventional connection terminal has the following problems.

First, in the connection terminal in which the copper plate 14 is soldered to the connection surface of the terminal body, since the soldering is a physical joining method, the soldering is performed according to the flatness of the copper plate 14 and the pressing conditions at the time of joining. At the same time, the joining state is different, and residues are generated due to inclusions and bubbles in the molten solder at the time of soldering. Due to the residues, unjoined portions remain at the boundary between the terminal body 11 and the copper plate 14. For this reason, the bonding strength between the terminal body 11 and the copper plate 14 is insufficient, so that the copper plate 1
4 may be peeled off from the terminal main body 11 and may not be able to transmit or receive power.

A copper plating layer 1 is formed on the entire surface of the terminal body 11.
Since the connection terminal formed with 5 consumes a large amount of copper plating solution, the production cost of the connection terminal is high, which is not preferable in actual production. On the other hand, only the copper plating layer 1
Although the connection terminal formed with 7 can reduce the manufacturing cost, since the terminal body 11 and the copper plating layer 17 are joined substantially in parallel, when a bending stress is applied, a tensile stress is applied to the boundary portion. This may cause the copper plating layer 17 to peel off from the terminal body 11 in some cases. For this reason, when the connection terminal is used outdoors or the like, when a bending stress is applied by wind force or the like, the copper plating layer 17 peels off, and power transmission or power reception cannot be performed.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a connection terminal which can prevent peeling of a copper plating layer and can reduce manufacturing costs.

[0012]

A connecting terminal according to the present invention is made of aluminum or an aluminum alloy and has a conductor extending from one end surface thereof, a connecting surface of the terminal body and a connecting surface opposite to the one end surface. And a copper plating layer formed only on the end face.

[0013]

In the present invention, a copper plating layer is formed on the end face of the terminal body opposite to the conductor connection end face, in addition to the connection face of the terminal body made of aluminum or aluminum alloy. Therefore, even if a bending stress is applied to the terminal main body in the longitudinal direction (the direction in which the conductor extends) and a stress acts in the direction of peeling the copper plating layer between the copper plating layer and the terminal main body, The copper plating layer formed on the opposite end face prevents a stress exceeding the peeling limit stress from acting between the copper plating layer and the terminal body. Therefore, peeling of the copper plating layer from the terminal body is avoided.

Since the copper plating layer is chemically bonded to the connection surface of the terminal body by plating, there is no unbonded portion unlike a conventional connection terminal in which a copper plate is soldered. Bonding strength between the metal and the copper plating layer is high.

Further, since the copper plating layer is formed only on the connection surface of the terminal main body and the end face on the opposite side, a copper plating solution is used in comparison with a conventional connection terminal in which the entire surface of the terminal main body is plated with copper. The consumption can be reduced, and the manufacturing cost can be significantly reduced.

Such a copper plating layer can be formed as described below. That is, after a portion of the terminal body where the copper plating layer is not formed is masked with a resin or the like, the terminal body provided with the mask is immersed in a plating bath. Thereby, a copper plating layer can be selectively formed on a predetermined portion of the terminal body.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a compression connection terminal according to an embodiment of the present invention, and FIG. 2 is a partially enlarged side view of a broken line portion A in FIG.

The aluminum terminal body 1 has a cubic shape, and a sleeve 2 is connected to one end surface in the longitudinal direction. The sleeve 2 has a cylindrical shape, and the electric wire is compressed and fixed in the cylinder. The electric wire and the terminal body 1 are electrically connected to each other via the sleeve 2. A base layer 3 is formed on the connection surface of the terminal body 1 and the other end surface in the longitudinal direction of the terminal body 1, that is, the end surface opposite to the one end surface to which the sleeve 2 is connected (hereinafter referred to as the other end surface). The copper plating layer 4 is formed on the surface of the underlayer 3. Further, a tin plating layer (or silver plating layer) 5 is formed on the surface of the copper plating layer 4.

It should be noted that the surface of the copper plating layer 4 is
Are provided. A plurality of bolt holes penetrating through the through hole are provided, and the compression connection terminal can be connected to a predetermined member by inserting a bolt into the bolt hole and fixing the bolt. For example, when interconnecting a pair of compression connection terminals,
The connecting surfaces are opposed to each other and fixed with bolts.

In the compression connection terminal thus configured, since the copper plating layer 4 is formed so as to extend from the connection surface of the terminal body 1 to the other end face, the terminal is bent in the longitudinal direction of the terminal body 1. Even if a stress is applied in the direction in which the copper plating layer 4 is peeled off, this stress can be prevented from exceeding the peeling limit stress of the copper plating layer 4. For this reason, peeling of the copper plating layer 4 from the terminal body 1 can be avoided. Further, since the copper plating layer 4 is formed only on the connection surface and the specific end surface of the terminal body 1, the consumption of the copper plating solution is smaller than that of the conventional compression connection terminal in which the entire surface of the terminal body 1 is plated with copper. The amount can be reduced, and the manufacturing cost can be significantly reduced.

Next, a description will be given of a result of actually manufacturing the compression connection terminal according to the present embodiment and comparing the peeling resistance of the compression connection terminal with the conventional one.

First, cuprous chloride was applied to the connection surface and the other end surface of the terminal body 1 and baked in an oven furnace to form the underlayer 3. Next, after the portion of the terminal body 1 that does not require plating is masked with a resin, the terminal body 1 is immersed in a copper sulfate bath, and copper plating is performed under the conditions of a liquid temperature of 25 ° C. and a current density of 2 A / dm ^2. By doing
The copper plating layer 4 was formed on the surface of the underlayer 3. Thereafter, the masking of the terminal body 1 was removed. Thus, the compression connection terminal according to the present example was manufactured.

Further, except that the formation portions of the underlayer, the copper plating layer and the tin plating layer are different,
The conventional compression connection terminal shown in FIG. 9 was manufactured. Note that FIG.
As shown in FIG. 4, the length of the compression connection terminal according to the embodiment and the conventional example is L.

The compression connection terminals according to the above embodiment and the conventional example were bent at different bending angles and bending radii, respectively, and their peeling resistance was examined. The results are shown in FIGS. FIG. 5 shows this embodiment, and FIG. 6 shows a conventional example. In FIG. 5, the case where there is no peeling is indicated by ○, and the case where there is peeling is indicated by x.

As apparent from FIGS. 5 and 6, the compression connection terminal according to the present embodiment does not peel off the copper plating layer from the terminal body even when bent at various bending angles and bending radii. The peel resistance was excellent. Also, when a predetermined heat cycle test was performed on this compression terminal, no particular abnormality was found.

On the other hand, the conventional compression connection terminal has a bending radius of L
When the bending angle was set to / 2π and the bending angle was set to 180 °, the boundary between the terminal body and the copper plating layer was peeled off at the end of the connection surface of the terminal body.

[0028]

As described above, according to the present invention, the copper plating layer is formed on the end face (the other end face) of the terminal body made of aluminum or aluminum alloy, which is opposite to the end face to which the conductor is connected. Therefore, even if bending stress is applied in the longitudinal direction of the terminal body, the copper plating layer can be prevented from peeling from the terminal body. Therefore, the connection terminal according to the present invention is of high quality, and can be used stably for a long period of time even outdoors.

Further, since the copper plating layer is formed only on the connection surface and the other end surface of the terminal body, the manufacturing cost can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a compression connection terminal according to an embodiment of the present invention.

FIG. 2 is a partially enlarged side view of a broken line portion A in FIG.

FIG. 3 is a perspective view showing a compression connection terminal according to the embodiment.

FIG. 4 is a perspective view showing a compression connection terminal according to a conventional example.

FIG. 5 is a graph showing the peel resistance of the compression connection terminal according to the embodiment.

FIG. 6 is a graph showing peel resistance of a compression connection terminal according to a conventional example.

FIG. 7 is a perspective view showing a conventional compression connection terminal.

FIG. 8 is a perspective view showing a conventional compression connection terminal.

FIG. 9 is a perspective view showing a conventional compression connection terminal.

[Explanation of symbols]

 1, 11; terminal body 2, 12; sleeve 3, 16; base layer 4, 15, 17; copper plating layer 5; tin plating layer 13; solder 14;

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-123658 (JP, A) JP-A-55-17954 (JP, A) JP-A-55-11128 (JP, A) JP-A-53-123 122790 (JP, A) JP-A-54-75585 (JP, A) JP-A-55-49875 (JP, A) JP-A-56-78175 (JP, U) JP-A-4-59071 (JP, U) 2-98775 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A terminal body formed of aluminum or an aluminum alloy and having a conductor extending from one end face thereof, a connecting face of the terminal body and an end face opposite to the one end face .
And a copper plating layer formed only on the connection terminal.