JP2000166074A - Terminal for connecting ground to shielding wire and method for connecting ground wire using the terminal for connecting ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method or a terminal for connecting ground, that can easily and rapidly connect a ground wire, prevent contact failures from occurring, and has improved shielding durability. SOLUTION: A terminal, for connection with a plurality of stripe junction parts 2 and 3 that are demarcated by a plurality of slits 1 which extend in the axial direction from the end part of a cylinder to a central part and a ground wire crimp part and a ground wire crimp part 4, is fitted to a shielding wire. The junction part 3, where the end part of the junction part is flexed from the center axis of the cylinder to the outside, is overlapped to the surface of a braid 30. The junction part 2, where the end part of the junction part extends straight, is inserted between the braid 30 of the shield wire and an insulation coating 20 that is located below the braid. A ground wire 5 is inserted into a ground wire crimping part 4 that is provided at the junction part 3, and the junction parts 2 and 3 for pinching the braid 30 and the grounding wire crimp part 4 are crimped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal for connecting an electric wire, and more particularly to a terminal for connecting an earth wire to a shielded wire used in, for example, an electronic circuit.

[0002]

2. Description of the Related Art For example, in a DC / DC converter for reducing a power output from a 300 V class battery of an electric vehicle to a 12 V class, frequency noise of 5 to 10 KHz is generated by switching ON / OFF of a switch at the time of pressure reduction.
The generated noise leaks to the outside in the case of a wire simply covered with a normal insulator. Noise emitted to the outside has an adverse effect on other electronic devices. Therefore, in electronic devices that operate at 12V, in order to prevent noise from leaking to the outside,
A shielded wire for noise is used in which the covered electric wire is further covered with a net-like conductor (braid) and further covered with an insulator.

[0003] Since noise flows through the braid, which is a conductor,
No release to the outside occurs. Since it is necessary to escape the noise flowing through the braid to the outside, attach a ground wire to the shielded wire and ground it to the body of the car.

FIG. 5 shows a method of attaching a ground wire to a shield wire. The shield wire includes a conductive wire 110, an insulating coating 120 on the conductive wire, a braid 130 made of a net-like metal, and an insulating coating 140 on the braid (FIG. 5A). First, only the insulating coating 140 is peeled off, so that the braid 130 is widely exposed. Subsequently, the braid 130 is loosened and bundled in a linear shape (FIG. 5B). The conductive wire 150 of the ground wire exposed to the linear braid 130 is tangled and connected. The connection part is covered by winding an insulating tape 160 (FIG. 5C).
This method is a method of directly connecting the braid and the ground wire without using the connection terminal. Therefore, there is an advantage that the adhesion between the shield wire and the ground wire is good.

FIG. 6 shows another mounting method. This method uses a connection terminal having a strip-shaped slit. First, peel off only the insulation coating 140,
The braid 130 is exposed. In this case, the exposed area of the braid does not need to be very large. Next, a band-like connection terminal 170 is wound around the braid 130 in the cross-sectional direction (FIG. 6B), and the exposed conductor 150 of the ground wire is inserted into the slit 180 of the shield terminal 170 and then crimped. An insulating tape 160 is wound thereon to cover (FIG. 6C). Compared with the former method, there is an advantage that the work of exposing the braid is small and the workability is good.

[0006]

However, in the former method of directly connecting the braid and the ground wire, the length of the braid exposed from the shield wire is required to be long. As a result, the work time required for unwinding and bundling the braid is reduced. There is a disadvantage in that the operation time of winding the tape at the joint where the braid and the conductor of the ground wire are entangled becomes long. In addition, since the unshielded conducting wire portion is long formed by bundling the braid, there is a possibility that noise may leak therefrom.

The latter method of using the connection terminal has good workability, but the connection terminal made of a hard metal is wound around a soft shielded wire and pressed from above, so that the shielded wire is easily deformed in the cross-sectional direction. There is a disadvantage that a space is generated between the braid and the connection terminal, the contact pressure is weakened, and poor contact is likely to occur. Further, the shielded wire using the connection terminal has a drawback that the shield has poor durability and noise is emitted from the connection portion. Therefore, a ground connection method or a connection terminal that can easily and quickly connect the ground wire, hardly cause poor contact, and has good shield durability is desired.

[0008]

According to a first aspect of the present invention, a plurality of strips defined by a plurality of cuts extending in an axial direction from an end of a conductive cylinder toward a center thereof are provided. A connection terminal for connecting an earth wire to a shielded wire provided with the joint portion of the above, and an earth wire crimping portion provided in the joint portion, wherein the earth wire is inserted into the joint portion and fixed by crimping. Is a joint where the end of the joint is bent outward from the center axis of the cylinder as compared to the center of the cylinder, and the first joint overlaps the braided surface of the shielded wire and the center of the cylinder In comparison, the end of the joint is bent inward from the center axis of the cylinder, or the joint extends straight from the center of the cylinder to the end of the joint without bending. The second contact inserted between the insulating coating and the And these joints are alternately arranged on the circumference of the cylinder, and one of the first joints is provided with the ground wire crimping part. .

According to a second aspect of the present invention, a shielded wire having a braid exposed is passed through the connection terminal from the joint portion side of the connection terminal by using the connection terminal according to the first aspect. Superimposing the first joint on the surface of the braid, inserting a second joint between the braid and an insulating film located below the braid, sandwiching both sides of the braid in a staggered manner with the joints, Through the ground wire crimping part, insert the ground wire exposing the conductive wire,
The shield wire and the ground wire are connected by crimping the bonding portion and the ground wire crimp portion sandwiching the braid.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a connection terminal according to an embodiment of the present invention. In this connection terminal, a plurality of slits 1 are provided in a cylindrical main body in the axial direction from the end to the center of the main body, and strip-like joints 2 and 3 are formed by the slit 1. I have. The bonding part 3 is provided with an earth wire crimping part 4 for penetrating an earth wire therein and fixing it by crimping.

The joint 2 extends straight from the cylindrical connection terminal without bending. The joint 2
Is a portion to be inserted between the braid of the shielded wire and the insulating coating on the conductive wire. In order to facilitate the insertion, it is desirable that the joint portion 2 bends inward from the central axis of the cylinder. The joint 3 has its end bent outward from the central axis of the cylinder. The joining portion 3 is a portion that is overlapped on the braid of the shield wire, and is directed outward so as not to be accidentally inserted between the braid and the insulating coating on the conductive wire and to be easily covered on the braid. Refracted. Joint 2
And 3 are alternately provided on the circumference of the cylinder, and have a structure in which the braid is sandwiched in a staggered manner.

The shape of the joints 2 and 3 is a strip in this embodiment, but by forming the slit 1 obliquely,
The end of the joint may be narrow or wide as shown in FIG. The expression "extends in the axial direction" includes not only a case in which it extends horizontally in the axial direction but also a case in which it extends obliquely in the axial direction. For example, by narrowing the tip of the joining portion 2, it becomes easy to insert between the braid and the insulating coating on the conductor.

As shown in FIG. 1, the ground wire crimping portion 4 has a hole structure so that the conductor of the ground wire 5 can be inserted therethrough. By crushing the head portion of the crimping portion 4 by crimping, the ground wire 5 comes into close contact with the connection terminal. The ground wire crimping portion 4 may have any shape as long as the conductive wire can be inserted and fixed therein, and may be a slit like a conventional technology. The ground wire crimping part 4 is provided on the joint part 3. By providing the ground wire crimping portion 4 at the joint 3 instead of the cylindrical portion of the connection terminal, the joints 2 and 3 and the ground wire crimping portion 4 can be crimped at the same time, thereby improving workability. This connection terminal is made of, for example, a tin alloy,
It has conductivity and can be easily deformed and easily pressed.

Next, a method of connecting the ground to the shield wire using the connection terminal will be described with reference to FIG. First, as shown in FIG. 3A, the shield wire is peeled off to expose the braid 30. Since the length of the braid to be exposed may be slightly longer than the length of the connection terminal, the workability for peeling off the insulating coating is improved as compared with the related art. At this time, the insulating coating 20 is also exposed.

Subsequently, the shield wire is inserted into the connection terminal so that the joints 2 and 3 of the connection terminal face the braid 30. Subsequently, all the joints 2 are inserted between the braid 30 and the insulating coating 20, and the joint 3 is covered on the braid 30. Subsequently, the ground wire 50 with the conductive wire exposed is inserted into the ground wire crimping portion 4. Note that, after the ground wire is inserted through the ground wire crimping portion 4, the joints 2 and 3 may be inserted into the braid or the like. Subsequently, the ground wire crimping part 4 and the braided parts 2, 3
Are simultaneously pressed by a pressing member (not shown). In this way, the braid 30 is sandwiched between the joints 2 and 3 in a staggered manner from both the front and back surfaces. The ground wire crimping portion 4 and the braided portions 2 and 3 may be separately crimped, but the crimping at the same time improves workability. Finally, the entire surface is covered with an insulating tape.

FIGS. 3C and 4 show the state after the pressure bonding. Since the braid 30 is pressed from both sides in a staggered manner by the joints 2 and 3, good adhesion can be obtained without depending on one place, and a reliable shielding effect can be expected.
In addition, since the connection terminals need only be inserted between the braids and crimped, the installation work time can be reduced to 1/10 or less compared to the conventional method of directly connecting the shield wire and the ground wire. The time required for grounding can be greatly reduced, and workability is greatly improved.

The durability of the shield of the connection terminal of the present invention was compared by the change in resistance between the ground wire and the braid when the thermal shock test was repeated several thousand cycles. The resistance value at the beginning of the test for both the conventional wound connection terminal and the connection terminal of the present invention was as low as 4 mΩ. -30 ° C to 80
As a result of repeating the thermal shock test at 2000 ° C for 2000 cycles, the conventional connection terminal shows a high resistance value of 2000 mΩ,
Although the shielding ability is reduced, the connection terminal of the present invention is 6 m.
It exhibited a low resistance value of Ω and very stable shield durability.

[0018]

According to the first aspect of the present invention, the connection terminal has a first joint bent outward from the central axis and a second joint bent inward or non-inward from the central axis. By being arranged alternately, the first joint portion is easily covered on the braid, and the second joint portion is easily inserted into a portion between the braid and the insulating coating.

Also, by being arranged alternately,
When the braid is assembled to the shielded wire, the braid is easily sandwiched from both sides in a staggered manner, so that the adhesion between the braid and the connection terminals can be improved. Further, it is possible to improve the durability of the shield effect of the contact portion.

According to the ground wire connection method of the second invention, it is possible to easily and quickly attach the ground wire to the shield wire, and work efficiency is improved as compared with the related art. In addition, by adopting this assembling method, the adhesion between the braid and the connection terminals is improved, and the durability of the shield can be improved. For this reason, the cost of the work of attaching the ground wire can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view and a cross-sectional view of a connection terminal according to the present embodiment.

FIG. 2 is a side view of a connection terminal according to another embodiment.

FIG. 3 is an explanatory diagram of a method of attaching a ground according to the present embodiment.

FIG. 4 is a cross-sectional view in the AA direction of a connection terminal terminal attached to the shielded wire of FIG. 3;

FIG. 5 is an explanatory view of a conventional method of attaching a ground wire.

FIG. 6 is an explanatory view of a conventional method of attaching a ground wire using a connection terminal.

[Explanation of symbols]

1 slit, 2, 3 joint, 4 ground wire crimp,
5, 50 ground wire, 10, 110 conductor, 20, 4
0, 120, 140 Insulation coating, 30 braids, 160
Insulating tape.

Claims (2)

[Claims] 1. A plurality of strip-shaped joints defined by a plurality of cuts extending in an axial direction from an end of a conductive cylinder toward a center thereof, and a plurality of strip-shaped joints provided at the joints, and a ground wire provided therein. A connection terminal for connecting an earth wire to a shielded wire having an earth wire crimping portion to be inserted and crimped and fixed, wherein the joining portion has a cylindrical end portion having a cylindrical end portion compared to a central portion of the cylindrical portion. A joint portion bent outward from the central axis, wherein the first joint portion is superimposed on the braided surface of the shielded wire; and the end portion of the joint portion is bent inward from the central axis of the cylinder as compared with the central portion of the cylinder. Or a joint extending straight from the center of the cylinder to the end of the joint without bending, wherein the second joint is inserted between the braid of the shield wire and the insulating coating located below the braid. These joints are alternately formed around the circumference of the cylinder. A connection terminal for connecting a ground wire to a shielded wire, wherein the connection wire is disposed on the top, and the ground wire crimping portion is provided at one of the first bonding portions. 2. The connection terminal according to claim 1, wherein a shield wire having a braid exposed is passed through the connection terminal from a joint portion side of the connection terminal, and the shield wire is formed on a braid surface of the shield wire. 1, a second joining portion is inserted between the braid and the insulating film located below the braid, and both sides of the braid are staggered in a staggered manner at the joining portion. A method of connecting an earth wire to a shielded wire, wherein the shielded wire and the grounding wire are connected by inserting a grounding wire exposing a conductive wire and crimping a bonding portion sandwiching the braid and an earthing wire crimping portion. .