JPH09185966A - Electric wire crimp terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obstruct the generation of a space between the inner surface of a conductor crimp piece and a conductor part even if a pair of facing conductor crimp pieces which holds and crimps the conductor part of an electric wire causes spring back after the crimp of the electric wire, and prevent the change of a crimp dimension and drop in a terminal characteristic. SOLUTION: The surface where a pair of facing conductor crimp pieces 3a of an electric wire crimp terminal 1 made of a metal thin plate, which holds and crimps the conductor part of an electric wire 4, comes in contact with each other is formed rough in a pear-skin pattern. Spring back is prevented, the conductor part is surely held without drop in the force holding the electric wire, and the intrinsic function of a terminal is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric wire crimping terminal which is caulked and fixed to an electric wire used for wiring an electric system of an automobile. After the wire is crimped, spring back is performed to prevent deterioration of the characteristics of the terminal at the crimping portion.

[0002]

2. Description of the Related Art Conventionally, there are wire crimp terminals shown in FIGS. That is, a pair of opposing conductor crimping pieces 3a for holding and crimping the conductor portion 4a of the electric wire 4 is provided on one side of the terminal board portion 2 formed of a thin metal plate, and adjacent to the conductor crimping piece 3a. A pair of wire crimping pieces 3b
Are provided so as to face each other, the covering portion 4b of the electric wire 4 is held and caulked and fixed to form the crimp portion 2A. An apparatus for crimping the electric wire 4 to the electric wire crimping terminal having the above structure is shown in FIGS. 9 and 10, for example. This is an electric wire between the male type portion 20 having the accommodation concave surface portion 20a for mounting the crimping portion 2A of the crimping terminal 1 provided on the upper surface and the pair of conductor crimping pieces 3a or the pair of electric wire crimping pieces 3b. After inserting and winding up the conductor portion 4a or the covering portion 4b of No. 4, a processing recess 21a having a substantially twin mountain shape for bending the pair of conductor crimping pieces 3a or wire crimping pieces 3b to face each other by pressing force is formed on the lower surface. It is formed of a female mold portion 21 that is formed so as to face the male mold portion 20 and is movable. Then, for example, the conductor portion 4a of the electric wire 4 from which the covering portion 4b is peeled off is bent by a pair of conductor crimping pieces 3a of the crimp terminal 1 facing each other by the pressure applied to the male mold portion 20 and the female mold portion 21. By doing so, as shown in FIG. 6 and FIG. 7, it is caulked and fixed in the held state.

[0003]

However, in the above-mentioned conventional wire crimp terminal, as shown in FIGS. 6 and 7, the conductor portion 4a is formed by bending the pair of conductor crimp pieces 3a so as to face each other under pressure. Even if they are caulked and fixed, even if no force is applied after crimping, the pair of conductor crimping pieces 3a generate springbacks f in opposite directions due to the elastic resilience of the metal.
Spring back f generated in the pair of conductor crimping pieces 3a
As a result, a space K is formed between the inner surface of the conductor crimping piece 3a and the conductor portion 4a as shown in FIG. And this space part K
As a result, the inner surface of the conductor portion 4a or the conductor crimping piece 3a in contact with the space K is easily oxidized in a heat resistant environment against the current flowing through the electric wire 4. Therefore, when this oxide layer expands, the conductor crimping pieces 3a slide with each other and the crimping dimension changes from the prescribed dimension H ₁ by the dimension h ₁ (see FIGS. 7 and 8).

FIG. 11 is a characteristic diagram showing the relationship among low voltage current resistance, terminal crimping strength, and terminal crimping height C / H.
In this characteristic diagram, when the terminal crimping strength indicated by the broken line d is increased to 30.0 to 60.0 (Kgf), the terminal crimping height C / H is the initial resistance in the range of 2.30 to 3.00. The value is increased as indicated by a broken line a, the resistance value at 150 hours when the heat resistance time can be seen is indicated by a broken line b, and the resistance value at 300 hours is increased by a broken line c. The 300-hour resistance value c is the conductor portion 4a of the electric wire 4.
When the terminal crimping strength (crimping force) with respect to (1) decreased from around the maximum point of 60.0 due to oxidation, etc., it rapidly increased. Therefore, the characteristics of the current flowing from the electric wire 4 to the electric wire crimp terminal are inconvenient, and the original function of the electric wire crimp terminal cannot be fulfilled.

The present invention solves the above-mentioned conventional inconveniences, and prevents the formation of a space between the inner surface of the conductor crimping piece and the conductor portion by the spring back of the pair of conductor crimping pieces to prevent oxidation and to perform crimping. Holds the conductor part securely without changing the processing dimensions and the holding force for the conductor.
Another object of the present invention is to provide a highly reliable wire crimping terminal that sufficiently fulfills the original function of the terminal without increasing the contact resistance between the wire crimping terminal and the conductor portion.

[0006]

In view of the above-mentioned problems, the first aspect of the present invention is a wire crimp terminal which is formed of a thin metal plate and has a pair of opposing conductor crimping pieces. A means was adopted in which the surfaces of the conductor crimping pieces to be contacted with each other were formed into a rough surface having a satin pattern.

According to a second aspect of the present invention, the rough surface having a satin pattern is formed by a knurling in which a plurality of parallel groove portions are crossed with each other in a crimp terminal having a plate thickness of 0.2 to 0.8 mm, A means is adopted in which the depth of the groove is formed to be about 1/10 of the thickness of the crimp terminal.

According to a third aspect of the present invention, in the knurled pattern having a satin pattern, the pitch between a large number of grooves intersecting each other is 0.2 to 0.5 mm, and the depth of the grooves is 0.
A means of forming the film with a thickness of 02 to 0.05 mm was adopted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete example of an embodiment of the present invention will be described below with reference to the drawings. 1 to 4 show an embodiment of the present invention. Reference numeral 1 denotes a crimp terminal formed of a thin metal plate. The crimp terminal 1 is provided with a pair of opposing conductor crimp pieces 3a, 3a on a crimp portion 2A on one side of the terminal board portion 2. The thickness t of the crimp terminal 1 is 0.2 to 0.8 mm. The conductor portion 4a of the electric wire 4 is clamped between the conductor crimping pieces 3a, 3a by caulking, so that the conductor portion 4a is fixed by the same constitution as the conventional electric wire crimping terminal shown in FIGS. Yes, the same parts are denoted by the same reference numerals.

However, in this embodiment, the conductor crimping pieces 3a, 3a are in contact with each other in a state in which the conductor portion 4a of the electric wire 4 is held between the pair of conductor crimping pieces 3a, 3a and they are caulked to face each other. Is formed on the rough surface S having a satin pattern.
As shown in FIGS. 2 and 3, the rough surface S is formed by a knurl 6 in which a large number of parallel groove portions 5 are crossed with each other in a metal thin plate having a plate thickness t of 0.2 to 0.8 mm. The knurl 6 has a pitch p between the grooves 5 as shown in FIG.
Is 0.2 to 0.5 mm, and the depth w of the groove 5 is about 1/10 of the plate thickness t of the crimp terminal 1. Specifically, the depth w of the groove 5 is 0.02 to 0.
It is 05 mm.

1 and 2, reference numeral 3b denotes a pair of electric wire crimping pieces provided adjacent to the conductor crimping piece 3a in the longitudinal direction of the crimping terminal 1, and the electric wire crimping piece 3b covers the electric wire 4. It is for crimping and fixing 4b.

An embodiment of the present invention has the above-mentioned configuration,
A pair of conductor crimping pieces 3a provided on the crimping portion 2A of the crimping terminal 1
The fact that the conductor portion 4a of the electric wire 4 is held between them and the conductor portion 4a is fixed by caulking them facing each other has the same effect as the conventional electric wire crimp terminal.

However, in the pair of conductor crimping pieces 3a of the present embodiment, the conductor crimping pieces 3a of the electric wire 4 are held and faced with each other in a crimped state. Since the rough surface S is formed on the surface S and frictionally engages with each other, the pair of conductor crimping pieces 3 are pressed after the conductor portion 4a is crimped.
A is prevented from slipping due to the springback f due to the elastic resilience of the metal.

The rough surface S has a plate thickness t of 0.2 to 0.8 mm.
1/10 of the crimp terminal 1 made of a thin metal plate
A large number of parallel grooves 5 having a depth w of about 0.02 to 0.05 mm are formed by knurls 6 intersecting each other with a pitch p of 0.2 to 0.5 mm. Therefore, when the conductor portion 4a of the electric wire 4 is caulked by the pair of conductor crimping pieces 3a, the groove portion 5 is not crushed by the pressing force and the plate thickness t of the crimp terminal 1 is 0.2 to 0.8 mm. Even if it is thin, the crimping terminal 1 and the conductor crimping piece 3a are guaranteed to have the necessary minimum mechanical strength, and the crimping force of the conductor portion 4a is securely held without being lowered. Moreover, the knurling 6 as a rough surface surely prevents the pair of conductor crimping pieces 3a from slipping due to the spring back f.

Therefore, the inner surface of the conductor crimping piece 3a and the electric wire 4 are
Unlike the conventional crimp terminal 1, the space portion K does not occur between the conductor portion 4a and the conductor portion 4a, so that the conductor crimping piece 3a in contact with the space portion K and the conductor portion 4a are prevented from being oxidized. .
The crimping dimension of the conductor crimping piece 3a with respect to the conductor portion 4a does not change from the specified dimension, and the contact resistance of the crimping terminal 1 against the current flowing in the wire 4 is prevented from increasing unlike the conventional wire crimping terminal. It Therefore, the original function of the terminal can be sufficiently ensured.

[0016]

As described above, according to the present invention, when crimping a conductor portion of an electric wire, the conductor crimping piece is squeezed so that the conductor crimping portion of the electric wire is held and opposed to each other. Since the rough surface is formed, the spring back of the pair of conductor crimping pieces prevents a space from being formed between the inner surface of the conductor crimping piece and the conductor portion, and prevents oxidation. Therefore, when the conductor crimping piece is crimped to the conductor portion, the crimping dimension of the conductor crimping piece does not change, and the holding force for the conductor portion does not decrease. Without increasing the contact area,
You can obtain a highly reliable product that fully demonstrates the original function of the terminal.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a usage state of a crimp terminal of the present invention.

FIG. 2 is a perspective view of an embodiment of the crimp terminal of the present invention before use.

FIG. 3 is also an enlarged front view showing a knurl forming a rough surface of the conductor crimping piece of the present embodiment.

FIG. 4 is a side view showing a groove portion of a knurl of the conductor crimping piece.

FIG. 5 is a perspective view showing a conventional crimp terminal for crimping an electric wire.

FIG. 6 is a sectional view showing a conventional crimp terminal in which a conductor portion of an electric wire is also crimped by a pair of conductor crimping pieces.

FIG. 7 is an enlarged cross-sectional view showing a conventional crimp terminal in a state in which a pair of conductor crimp pieces also have springback.

FIG. 8 is an enlarged cross-sectional view showing a conventional crimp terminal in which a gap is similarly formed between the conductor crimping piece and the conductor portion of the electric wire.

FIG. 9 is a perspective view showing a conventional crimping device for crimping an electric wire to an electric wire crimping terminal.

FIG. 10 is a front view illustratively showing a state in which electric wires are crimped using the crimping device shown in FIG. 9.

FIG. 11 is a characteristic diagram showing a relationship between a low-voltage current resistance and a terminal crimp strength in a conventional crimp terminal.

[Explanation of symbols]

 1 Crimping terminal 2 Terminal board part 3a Conductor crimping piece 3b Electric wire crimping piece 4 Electric wire 4a Conductor part 5 Groove part 6 Knurled f Spring back S Rough surface t Plate thickness w Depth

[Procedure amendment]

[Submission date] May 30, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction contents]

[0003]

However, in the above-mentioned conventional wire crimp terminal, as shown in FIGS. 6 and 7, the conductor portion 4a is formed by bending the pair of conductor crimp pieces 3a so as to face each other under pressure. Even if they are caulked and fixed, even if no force is applied after crimping, the pair of conductor crimping pieces 3a generate springbacks f in opposite directions due to the elastic restoring property of the metal.
Spring back f generated in the pair of conductor crimping pieces 3a
As a result, a space K is formed between the inner surface of the conductor crimping piece 3a and the conductor portion 4a as shown in FIG. And this space part K
Heat is generated by the electric current flowing through the electric wire 4, and the conductor portion 4a or the conductor crimping piece 3a that is in contact with the space K in the heat-resistant environment is generated.
The inner surface of the is easily oxidized. Therefore, this oxide layer expands and
Due to the thermal expansion force of the metal and the metal , the conductor crimping pieces 3a slide with each other, and the crimping dimension changes from the prescribed dimension H ₁ by the dimension h ₁ (see FIGS. 7 and 8).

Claims (3)

[Claims] 1. An electric wire crimping terminal, which is formed of a thin metal plate and has a pair of opposing conductor crimping pieces, wherein the conductor crimping pieces that embrace and crimp the conductor portion of the electric wire have a matte textured rough surface. Wire crimp terminal characterized by being formed on the surface. 2. The rough surface having a satin pattern has a plate thickness of 0.2 to
A large number of parallel grooves are formed on the 0.8 mm crimp terminal by knurls intersecting each other, and the depth of the groove is formed to be about 1/10 of the plate thickness of the crimp terminal. The electric wire crimp terminal according to claim 1, which is characterized in that. 3. The knurled pattern having a satin pattern has a pitch between a plurality of mutually intersecting grooves of 0.2 to 0.5 mm and a depth of the grooves of 0.02 to 0.05 mm. The wire crimp terminal according to claim 1 or 2, characterized in that.