JP2000268642A - End structure of extra fine wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To materialize at a low cost an end structure of an extra fine wire usable suitably for an earth wire for a back light lamp of a liquid crystal display used for a laptop personal computer and a Japanese word processor, wherein an end structure having a fine diameter has been strongly desired. SOLUTION: In this end structure of an extra fine wire 1, the extra fine wire 1, to which a thin insulating coating 3 having a thickness of not more than 0.25 mm is applied on the periphery of a conductor formed by disposing a copper wire or a copper alloy wire around a body having high strength and a high tensile force, is connectively caulked to a crimp terminal 11 fitting to the outer diameter of a soft copper coated wire with rupture strength equivalent to the rupture strength of the extra fine wire 1. A reinforcing material having conductivity is coated on a conductor exposed by stripping the insulating coating 3 at the end of the extra fine wire 1, the end of the insulating coating is closely covered by a spacer 5, and under this condition, the extra fine wire 1 is connectively caulked to the crimp terminal, in this structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal structure of an ultrafine electric wire which can be suitably used, for example, as a ground wire for a backlight lamp of a liquid crystal display used in a notebook personal computer or a Japanese word processor. In particular, the terminal portion of the ultrafine wire having a finish outer diameter of 0.6 mm or less and a crimp terminal suitable for an electric wire having a finish outer diameter of about 1.1 to 1.6 mm having a breaking strength equivalent to the fine wire are sufficiently provided. The present invention relates to a device devised so that connection can be performed with a high connection strength (terminal crimp strength).

[0002]

2. Description of the Related Art Liquid crystal displays are widely used in notebook personal computers and Japanese word processors because of their small thickness and low power consumption. If the state is bad, the display becomes extremely difficult to see. Therefore, in a device having a relatively large power supply or a device using an AC power supply, a backlight lamp is installed as a lighting source on the back side so that the display can be seen regardless of the external light amount or the lighting state. As the backlight lamp, a cold-cathode fluorescent lamp, which has a feature that a sufficient amount of light is obtained, a small amount of heat is generated, and a long service life, is used. This cold cathode fluorescent lamp has a structure in which a normal fluorescent lamp for lighting is miniaturized, and AC1k obtained by increasing the voltage of its electrode by a DC-AC converter or the like.
Light is emitted by applying a high voltage of V or more.

Conventionally, a driving frequency of 50 to 60 kHz has been used as a high-voltage side lead wire in this type of backlight lamp.
z, various high-voltage electric wires with a driving voltage of 1.0 to 3.0 kV,
For example, the outer periphery of a conductor formed of a tin-plated soft copper wire or a tin-plated soft copper stranded wire is covered with an insulator such as silicone rubber, cross-linked polyethylene, or a fluororesin by extrusion coating.
An electric wire of about 1.6 mm is used. One end of these lead wires is connected directly to the electrode portion of the backlight lamp by soldering, and the other end is crimped to a crimp terminal having a housing fitting portion, a conductor crimping portion, and an insulator crimping portion. After that, it is mounted on a housing having a predetermined shape by fitting and is electrically connected to the inverter circuit board. Here, the connection strength (terminal crimp strength) between a conventionally used high-voltage wire and a crimp terminal is 1.80 to 1.95 k.
gf.

[0004] On the other hand, as a ground side lead wire in a backlight lamp, for example, a finish in which an insulator such as a cross-linked vinyl chloride resin or cross-linked polyethylene is extrusion-coated around a conductor made of a tin-plated soft copper wire or a tin-plated soft copper stranded wire. An insulator such as a polyester film disposed on both upper and lower surfaces of a conductor made of a low piezoelectric wire having an outer diameter of about 1.3 to 1.5 mm or a tin-plated soft copper wire or a tin-plated copper foil was fused and integrated by lamination or the like. 0.25-0.30m thickness
A tape wire of about m is used.

[0005] Among these ground-side lead wires, one end of the low-voltage wire is connected directly to the electrode portion of the backlight lamp by soldering similarly to the high-voltage side lead wire, and the other end is connected to the housing fitting portion. Then, it is caulked and connected to a crimp terminal having a conductor crimp portion and an insulator crimp portion, and then fitted to a housing having a predetermined shape by fitting to be electrically connected to the inverter circuit board. Here, the connection strength between the conventionally used low-voltage wire and the crimp terminal (terminal crimp strength)
Is about 1.80 to 1.95 kgf.

In the case of a tape electric wire, another electric wire is connected to both ends thereof using connection terminals and the like, and their terminal portions are connected to the electrode portion of the backlight lamp and the inverter circuit board by soldering, respectively. .

In recent years, the thickness of the liquid crystal display has been reduced and the size of the backlight lamp has been reduced. As a result, a space reduction of about 0.1 mm has been made around the backlight lamp, particularly around the reflector for fixing and holding the backlight lamp. Has been requested. In order to respond to such a demand for space saving, it is conceivable to reduce the diameter of the high-voltage side lead wire and the ground-side lead wire used to be connected to the backlight lamp. Since it is difficult to reduce the diameter more than the current state due to the withstand voltage characteristics, it is currently strongly desired to reduce the diameter of the ground-side lead wire.

[0008]

However, the above-mentioned conventional ground side lead wire has the following problems. First, in the case of a low piezoelectric wire in which a conductor is coated with a cross-linked vinyl chloride resin or cross-linked polyethylene as an insulator, since the finish outer diameter is limited to about 1.3 mm to 1.5 mm as described above, a tape is used. Wire thickness is 0.3mm
Considering the following, it is not possible to find an advantage in terms of space saving.

[0009] On the other hand, in the case of a tape wire, although it is satisfactory in terms of space saving, special processing is required for connection with a backlight lamp and an inverter circuit board, and the price of the wire itself is very high. However, since it is expensive, there is a practical problem in terms of cost. Furthermore, flexibility,
Since the mechanical properties such as the bending property and the tensile strength are remarkably inferior to those of general electric wires, there is a possibility that the conductor may be broken at the time of wiring work if care is not taken sufficiently.

The present invention has been made on the basis of the above points, and an object thereof is, for example, a liquid crystal display used in a notebook personal computer or a Japanese word processor for which a reduction in diameter is strongly desired. Another object of the present invention is to realize a terminal structure of an ultrafine electric wire which can be suitably used as a ground wire for a backlight lamp at a low cost.

[0011]

According to the present invention, there is provided a terminal structure for an ultra-fine wire according to the present invention, wherein a copper wire or a copper alloy wire is arranged around a high-strength tension member and has a thickness of 0 mm. The terminal structure of an ultra-fine electric wire for crimping an ultra-fine electric wire coated with a thin insulating coating of 25 mm or less with a crimp terminal adapted to the outer diameter of a soft copper-coated electric wire having a breaking strength corresponding to the breaking strength of the ultra-fine electric wire. The conductor exposed by stripping the insulating coating at the end of the ultrafine wire is coated with a conductive reinforcing material, and the end of the insulating coating is covered with a spacer in close contact with the conductor. It is characterized in that it is swaged to a terminal.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION
It has a configuration in which a thin insulating coating having a thickness of 0.25 mm or less is provided on the periphery of a conductor in which a copper wire or a copper alloy wire is disposed around a high-strength tension body.

Examples of the high tensile strength material include ultrafine steel wire such as stainless steel wire, and high strength and high modulus fiber such as aromatic polyamide fiber and wholly aromatic polyester fiber. Each of these fibers has excellent properties such as a tensile strength of 200 kg / mm ₂ or more and an elastic modulus of 7000 kg / mm ₂ or more. In addition, as a copper wire or a copper alloy wire disposed around the high tension body, in addition to a normal copper wire or a copper alloy wire,
Examples thereof include a tin-containing copper wire or a tin-containing copper alloy wire containing a predetermined amount of tin, and further, a nickel-plated or tin-plated surface thereof. Any of these may be used, but those containing tin are particularly preferred because of their excellent tensile strength and flex resistance.

The constituent material of the insulation coating on the conductor periphery is not particularly limited. For example, ethylene tetrafluoride-6
Fluorine-based materials such as propylene fluoride mixtures, ethylene-tetrafluoroethylene copolymers, and polyvinylidene fluoride are particularly preferable because they exhibit sufficient mechanical strength even with a thin coating of 0.25 mm or less.

As a specific example of the ultrafine electric wire obtained from these constituent materials, for example, a tin-plated hard tin-containing copper alloy wire 8 having a wire diameter of 0.05 mm is wound around a high-strength tensile body made of an aromatic polyamide fiber. An outer diameter of 0.25 mm, AWG # 3, obtained by spirally winding this aligned product spirally at a predetermined pitch
6 is a fluororesin insulated wire having a finish outer diameter of 0.53 mm formed by extruding a 0.14 mm-thick thin insulating coating made of a mixture of ethylene tetrafluoride and hexafluoropropylene on the circumference of the conductor No. 6 .

As described above, this wire has a conductor size of AWG # 36 and a finish outer diameter of 0.53 mm, which is an extremely small diameter.
An outer diameter of 0.7 mm of seven 16 mm tinned annealed copper wires.
Equivalent to the breaking strength (approximately 3.53 kgf) of a silicone rubber insulated wire with a finish outer diameter of 1.4 mm in which an insulation coating made of silicone rubber having a thickness of 0.381 mm is formed on the conductor circumference of 48 mm AWG # 26. The above breaking strength (about 4.
4 kgf).

The soft copper-coated electric wire is, for example, an electric wire having a structure in which an insulator such as silicone rubber, cross-linked polyethylene, or fluororesin is extrusion-coated on a conductor made of tin-plated soft copper wire or tin-plated soft copper stranded wire. This corresponds to, for example, various high-voltage electric wires used as a high-voltage side lead wire for a backlight lamp of a liquid crystal display. The finish outer diameter of the high voltage wire for the backlight lamp is as follows.
Since the diameter is about 1 mm to 1.6 mm, the ultrafine electric wire according to the present invention has a breaking strength equal to or more than that of the high-voltage electric wire while having an outer diameter of 1/3 or less.

The crimp terminal used in the present invention is a terminal adapted to the outer diameter of the above-mentioned soft copper-coated electric wire, such as a high-voltage side lead wire for a backlight lamp or a ground side lead of a liquid crystal display. It corresponds to a crimp terminal crimped to the end of various high-voltage wires or low-voltage wires used as wires. Such a crimp terminal 11
As shown in FIG. 1, the shape is formed by a housing fitting portion 12 that fits into a housing (not shown), a conductor crimping portion 13, and an insulator crimping portion 14.

In this crimp terminal 11, the conductor crimping portion 13 and the insulator crimping portion 14 are made of soft copper-coated electric wires (high-voltage wires, low-voltage wires).
Therefore, it is impossible to obtain a sufficient connection strength (terminal crimp strength) even if it is designed to be connected to the ultrafine electric wire according to the present invention as it is.

Therefore, according to the present invention, the conductor exposed by stripping the insulating coating at the end of the ultrafine wire is coated with a conductive reinforcing material, and the end of the insulating coating is covered with a spacer in close contact with the conductor. By crimping connection to the crimp terminal in that state, 1.8 equivalent to the conventional one is obtained.
A sufficient connection strength (terminal crimp strength) of about 0 to 1.95 kgf is obtained.

Here, as the reinforcing material to be coated on the conductor of the ultrafine wire, for example, a copper terminal, a brass terminal, a copper sleeve,
Examples include a brass sleeve, a copper foil, a brass foil, and a solder. Examples of the spacer include an insulating tube such as a heat-shrinkable cross-linked polyethylene tube and a silicone rubber tube, a copper terminal, a brass terminal, and the like.
Note that the reinforcing material and the spacer do not necessarily need to be separately configured, and may be configured in series with, for example, a copper terminal, a brass terminal, or the like.

Here, when connecting a crimp terminal having a configuration in which a conductor crimping portion and an insulator crimping portion are usually connected to an electric wire, the crimping terminal should be adjusted according to the conductor diameter of the electric wire and the finish outer diameter. Is generally selected, it is considered that a small crimp terminal suitable for the conductor diameter and finish outer diameter of the ultrafine wire should be similarly selected in the ultrafine wire according to the present invention. However, the present invention did not employ such a method for the following reasons.

That is, as described above, the crimp terminal used in the present invention is caulked to, for example, the terminal portion of a high-voltage lead (high-voltage wire) or a ground-side lead (low piezoelectric wire) in a backlight lamp of a liquid crystal display. After being connected, it is mounted by fitting into a housing formed into a predetermined shape. At this time, if the shape and size of the crimp terminal are designed to be small in accordance with the ultra-fine electric wire, the size of the housing must be redesigned accordingly. Redesigning both the crimp terminal and the housing would result in a significant increase in cost. Furthermore, in the connection between such a small crimp terminal and the housing, it is impossible to obtain the same connection strength as that obtained by connecting the existing crimp terminal to the housing.

On the other hand, as described above, the connection structure of the present invention makes it possible to connect an extra-fine wire to a crimp terminal while using an existing crimp terminal fitted to a housing by fitting. Therefore, sufficient connection strength between the crimp terminal and the housing is not impaired at all.
Further, since the materials to be used are only known reinforcing materials and spacers which can be easily obtained, the cost does not increase.

Therefore, when this terminal structure is applied to, for example, a ground wire for a backlight lamp of a liquid crystal display, it is possible to realize a significant space saving at a low cost.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In this embodiment, it is assumed that the present invention is applied to a ground wire for a backlight lamp of a liquid crystal display used in a notebook personal computer.

First, the ultrafine electric wire 1 used in this embodiment is as follows.
As shown in FIG. 1, a wire diameter of 0.05 around a high-strength tensile body made of an aromatic polyamide fiber having a thickness of 200 deniers.
mm tin-plated hard tin-containing copper alloy wire (TH-SNCC-
3) AWG # 36 conductor 2 having an outer diameter of 0.25 mm and spirally wound horizontally at a pitch of about 0.8 mm with eight aligned wires
A thin insulating coating 3 having a thickness of 0.14 mm made of a mixture of tetrafluoroethylene and hexafluoropropylene is formed of a fluororesin insulated wire having a finish outer diameter of 0.53 mm formed by extrusion coating. . In addition, the breaking strength of this extra fine wire was about 4.4 kgf. The breaking strength was determined by fixing one end of the ultrafine wire, pulling the other end in the longitudinal direction while checking conduction, and measuring the strength when the wire was disconnected.

Next, as shown in FIG. 1, the crimp terminal 11 is formed by pressing a tin-plated phosphor bronze plate, and includes a housing fitting portion 12 for fitting with a housing (not shown). A conductor crimping portion 13 for crimping the conductor portion 2 of the microfine wire 1 and an insulator crimping portion 14 for caulking the insulating coating portion 3 of the microfine wire 1 are provided.

In this embodiment, the above-described microwire 1 and crimp terminal 11 were connected in the following procedure to obtain a terminal structure as shown in FIG. First, as shown in FIG. 1, the insulating coating 3 at the end of the ultrafine wire 1 was stripped by about 3 mm by a wire stripper to expose the conductor 2.
Next, the inner diameter of the spacer 5 is 0.6 mm and the thickness is 0.5 m.
m, a silicone rubber tube having a length of 10 mm is tightly coated on the end of the insulating coating 3, and the conductor 2 has a thickness of 0.25 mm as a conductive reinforcing material 4.
A brass terminal having a length of 3.0 mm was crimped. Then, the conductor portion 2 covered with the brass terminal 4 of the ultrafine wire 1 is placed on the conductor crimping portion 13 of the crimp terminal 11, and the insulating covering portion 3 covered with the silicone rubber tube 5 is placed on the insulator crimping portion 14. In this state, the conductor crimping portion 12 and the insulator crimping portion 14 of the crimp terminal 11 were caulked.

Here, in order to evaluate the connection strength (terminal crimping strength) at the connection portion between the ultrafine electric wire and the crimp terminal according to the present embodiment, as a comparative example, the ultrafine electric wire according to the present embodiment was compared with a conventional liquid crystal display. The following test was performed by preparing a substitute for the high-voltage electric wire used as the high-voltage side lead wire for the backlight lamp. As a high-voltage electric wire, an outer diameter of 0.48 mm obtained by twisting seven tin-plated annealed copper wires having a wire diameter of 0.16 mm, and an insulating coating made of silicone rubber having a thickness of 0.381 mm made of silicone rubber is provided on the conductor circumference of AWG # 26. A formed silicone rubber insulated wire (break strength: 3.53 kgf) having a finished outer diameter of 1.4 mm was used.

Each wire was pulled vertically using a tensile tester (push-pull gauge), and the value when each wire was pulled out from the crimp terminal was measured as the connection strength (terminal crimp strength).

As a result, the weight of the comparative example was 1.90 kgf, whereas that of the present example was 2.10 kgf. Considering that the finish outer diameter of the wire used in this example is 0.53 mm and the breaking strength is 4.4 kgf, the finish outer diameter of the wire used in the comparative example is 1.4 mm and the breaking strength is 3.53 kgf. It can be seen that the device according to the present example can secure a breaking strength and a terminal crimping strength equal to or higher than those of the related art while realizing a significant reduction in diameter.

[0033]

As described above in detail, according to the present invention, the end portion of the ultrafine wire having a finish outer diameter of 0.6 mm or less, and the finish outer diameter of 1.1 to 1.0 having the same breaking strength as the ultrafine wire. 1.6m
It is possible to connect a crimp terminal suitable for an electric wire of about m with sufficient connection strength (terminal crimp strength). Therefore, if this terminal structure is applied to, for example, a connection portion such as a ground wire for a backlight lamp of a liquid crystal display used in a notebook personal computer or a Japanese word processor for which a reduction in the diameter is strongly desired, it is possible to reduce the size of the conventional structure. Thus, it is possible to significantly reduce costs.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the present invention, and is a perspective view of an ultrafine wire, a conductive reinforcing material, a spacer, and a crimp terminal.

FIG. 2 is a view showing one embodiment of the present invention, and is a plan view showing a state in which a microwire and a crimp terminal are connected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrafine electric wire 2 Conductor (conductor part) 3 Thin insulation coating (insulation coating part) 4 Conductive reinforcing material (brass terminal) 5 Spacer (silicone rubber tube) 11 Crimp terminal 12 Housing fitting part 13 Conductor crimp part 14 Insulation Body crimping part

Claims (1)

[Claims] An ultra-thin electric wire having a thin insulating coating with a thickness of 0.25 mm or less applied around a conductor in which a copper wire or a copper alloy wire is arranged around a high-strength tension body is broken. A terminal structure of an extra fine wire to be caulked and connected to a crimp terminal adapted to the outer diameter of a soft copper covered electric wire having a breaking strength corresponding to the strength, and a conductor exposed by stripping an insulating coating at an end portion of the extra fine wire. A terminal structure for an ultrafine electric wire, characterized in that a terminal is coated with a reinforcing material having conductivity, and a terminal of the insulating coating is covered with a spacer in a tightly contacted state, and in this state, the terminal is crimped to the crimp terminal.