JP2001135151A - Pressure-contact wire and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a fastening force between a core wire and an insulating coating material of a pressure-contact wire. SOLUTION: The pressure-contact wire has a core wire 12 as a conductor coated with an insulating coating material 13 formed of an insulating resin and connected to a pressure-contact terminal 6. A number of small grooves 11a are formed on the surface of a portion contacting the insulating coating material of the core wire 12, and the insulating resin for the insulating coating material is adhered to the grooves so as to be bitten therein, thereby improving the fastening force between the core wire and the insulating coating material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press-connecting wire and a method for manufacturing the same, and more particularly, to a press-connecting terminal and a wire connected to the press-connecting terminal. This is to prevent the insulating coating material divided at the connection position from being displaced from the core wire.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 5, an electric wire 1 is formed by twisting a plurality of (in the case of FIG. 7) strands 3 around a core wire 2 around which an insulating material such as a vinyl chloride resin (PVC) is applied. An insulating coating material 4 made of resin is coated. Note that there is also a single core wire using one thick core wire as the core wire 2. In either case of the stranded wire or the single-core wire, since the strand 3 is formed by drawing from a thick wire to a thin wire through a plurality of dies, the outer peripheral surface is smoothened to a mirror surface.

[0003] There are a crimp terminal and a press contact terminal as terminals to be connected to the electric wire, and the press contact terminal has recently been widely used because automatic connection of the terminal to the electric wire is easy. For example,
As shown in FIGS. 6 and 7, when the electric wire 1 is pushed into the press-fitting slot 6 a of the press-fitting terminal 6 mounted in the press-fitting connector 5, the press-connecting blade 6 b formed on the peripheral surface of the press-fitting slot 6 a becomes Is cut, and the inner core wire 2 is directly in contact with the press contact terminal 6 to achieve electrical conduction.

[0004]

As described above, the wire 3 constituting the core 2 of the conventional electric wire 1 has an extremely smooth surface and a small surface roughness as described above. The adhesion at the interface with the coating material 4 is insufficient. Therefore, as described above, this electric wire 1 is
When the connection is made, the insulating coating material 4 is cut off,
When the insulating coating material 4 is cut off at the connection portion with
Slippage easily occurs between the strand 3 and the insulating coating material 4. As a result, as shown in FIGS. 6 and 7, a gap C is generated between the press contact terminal 6 and the cut end surface 4 a of the insulating coating material 4, and the inner core wire 2 is exposed to the outside, and is likely to be defective. There was a problem.

As described above, the press contact terminal 6 and the insulating coating material 4
When a gap C is generated between the pressure contact terminals 6
Since the gripping force by pinching both sides of the
When mechanical vibration or the like is applied from the outside, the electric wire 1 and the press contact terminal 6 are easily detached, and the electrical connection reliability is reduced. Especially, AWG (American wiring gage) 0.1 ~
In the case of the small-diameter electric wire of 0.08 sq, the surface area of the core wire 2 is small, so that the contact area with the insulating coating material is small. Therefore, the fixing force is inferior, and the displacement between the core wire and the insulating coating material easily occurs.

[0006] As a method of inspecting the connection strength in the crimping connection, there is a case where the electric wire 1 pulled out from the crimping connector is lifted upward perpendicular to the wire drawing direction, and the difficulty of detachment of the electric wire 1 at that time is examined. is there. At the time of this inspection, due to poor adhesion between the core wire 2 and the insulating coating material 4, the electric wire 1 separates from the crimp terminal 6 from the connection point of the crimp terminal 6, comes out of the crimp connector, and fails to inspect. May pass.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and in a wire to be connected to a press-connecting terminal (hereinafter referred to as a press-connecting wire), the fixing force between a core wire and an insulating coating material is increased. An object is to prevent the insulating coating material from moving or peeling off from the core wire.

[0008]

In order to achieve the above-mentioned object, the present invention provides a method for manufacturing a semiconductor device, wherein a core wire serving as a conductor of an electric wire is covered with an insulating coating material made of an insulating resin, and the insulating coating material is used as a press-connecting terminal. A press-connecting wire cut by a press-connecting blade and electrically connected by contact between the core wire and the press-connecting blade, wherein a surface of a portion of the core wire in contact with the insulating coating material is provided with a large number of fine grooves. A press-fitting electric wire characterized in that an insulating resin of an insulating coating material is closely attached to the core wire so as to dig into the insulating coating material, thereby increasing a fixing force between the core wire and the insulating coating material.

The groove is in the form of a streak extending in the axial direction, and the conductor is formed by twisting one core wire or a plurality of strands. If the strand is twisted, the conductor is twisted. The groove is provided at a position that becomes the outer peripheral surface in the combined state.

[0010] In particular, the pressure welding wire to which the present invention is applied is suitably applied to a small diameter wire. The small-diameter electric wire has a strand diameter of about 0.1 to 0.2 mm, and a core wire obtained by twisting the strands of about 0.4 to 0.5 mm. Therefore, the depth of the groove provided on the surface of the strand is set to about 10 to 90 μm.

As described above, since a large number of minute grooves are provided on the outer peripheral surface of the core wire, the substantial area of the outer peripheral surface of the core wire becomes larger than before the groove is provided, and the core wire and the insulating resin are formed. And the groove is filled with the insulating resin, so that the adhesion between the core wire and the insulating coating material can be improved. Therefore, when this press-connecting wire is connected to the press-connecting terminal, slippage between the core wire and the insulating coating material is less likely to occur, and a gap is generated between the press-connecting terminal and the separated insulating coating material on both sides, thus resulting in a core wire. Can be prevented from being exposed, and both sides of the press contact terminal can be sandwiched between the insulating coating materials on both sides, so that the connection strength is increased and the electrical connection reliability can be improved.

Further, the present invention provides a method for manufacturing the press-connecting wire, in which a micro-groove is passed through a die having an inner periphery in a step before the covering step with the insulating resin, thereby forming an outer periphery of the core wire. The present invention provides a method for manufacturing a wire for press-fitting, in which a large number of minute grooves are provided on a surface, and in a coating step with an insulating resin, the insulating resin is brought into close contact with the core groove so as to bite into the minute groove. .

[0013] The dice provided with the minute grooves on the inner peripheral surface are:
For example, axially extending ridges are formed on the inner peripheral surface at intervals in the circumferential direction, and when the core wire passes through the die, an axial groove is formed on the outer peripheral surface. Like that. This makes it possible to extremely easily form a large number of microgrooves on the surface of the core wire without providing a large-scale facility, and to enhance the adhesion between the core wire and the insulating coating material in the subsequent step of coating with the insulating resin. be able to.

Before the step of coating with the insulating resin, before or after passing through the die, the core wire is preheated to reduce the temperature difference from the insulating resin to be injected,
The core wire is softened to reduce the resistance and ensure the filling of the groove.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. Insulation wire 10 of the present invention
As shown in the cross-sectional view of FIG. 1, a core wire 12 formed by twisting a plurality of wires (7 in the illustrated case) such as a copper wire.
Insulation coating material 13 such as vinyl chloride resin (PVC)
Is configured.

Each wire 11 of the press-connecting wire 10 has an outer diameter of about 0.1 mm to 0.08 mm, and extends in an axial direction on an outer peripheral surface in contact with the insulating coating material 13 in a twisted state. A large number of streak-like grooves 11a are formed along the circumferential direction, and there are many fine saw-tooth-shaped irregularities when viewed in cross section.
1 has a large surface roughness. As described above, by roughening the mirror surface of the wire 11, the substantial surface area in the circumferential direction of the wire 3 becomes larger than that of a simple circular shape. Adhesion with the insulating coating material 13 can be improved.

The press-connecting wire 10 shown in FIG.
It is manufactured by the process shown in FIG. In the drawing, reference numeral 20 denotes an assembling die, 21 denotes a cylindrical preheater provided with a ceramic heater or the like, 22 denotes a groove forming die, 23 denotes an insulating resin supply hopper, and 24 denotes an extruder. As shown in FIG. 2 (B), the groove forming die 22 has a long and narrow axially extending convex portion 22a formed on the inner peripheral surface in the circumferential direction.

As shown in FIG. 2A, first, a plurality of strands 11 are gathered and twisted by an assembling die 20, and are passed through the assembling die 20 to form a core wire 12 made of a stranded wire. You. Next, the core wire 12 is passed through a preheater 21 to be heated. The heating temperature in this case is set to, for example, about 210 ° C. As a result, the temperature of the core wire 12 approaches the extrusion temperature of the insulating coating material 13 to reduce the temperature difference therebetween, and the insulating coating material 13
To improve adhesion when coating.

Subsequently, the preheated core wire 12 is passed through the groove forming die 22. At this time, on the surface of each of the wires 11 constituting the core wire 12 in contact with the insulating coating material 13, a large number of groove 11a having a streak shape extending in the axial direction are formed along the circumferential direction to increase the surface roughness. For this reason, it is possible to enhance the adhesion when the insulating coating material 13 is subsequently coated. Moreover, by using such a groove forming die 22, it is possible to extremely easily provide a large number of minute grooves on the surface of the core wire 12 without providing a large-scale facility.

Next, an insulating coating material 13 made of an insulating resin is supplied from a hopper 23, and is extruded by an extruder 15 to cover the outer periphery of the core wire 12 with the insulating coating material 3 so that the press-connecting electric wire shown in FIG. 10 is obtained.

The manufacturing method of the present invention is not limited to the above embodiment. A groove forming die 22 is provided on the inlet side of the preheater 21, and the surface of the core wire 12 is roughened and then preheated to form the insulating coating material 13. It may be covered with. Further, a groove forming die 2
It is also possible to adopt a configuration in which the die 2 and the assembly die 20 are united, and the groove forming die 22 is continuously provided on the outlet side of the assembly die 20. Furthermore, the preheater 21 may be provided on both the inlet side and the outlet side of the groove forming die 22. In any case, the distance from the collecting die 20 to the extruder 23 is 100 m or less, and the core wire 12 is conveyed at 400 m / min. Therefore, in the step before the step of coating the surface of the core wire 12 with the insulating coating material 13. If the core wire 12 is preheated, the temperature difference at the time of coating the insulating coating material 13 is reduced, and the adhesion can be improved.

In the above-described embodiment, the core wire 12 is formed by twisting the plurality of strands 11, but the core wire 12 may be formed from one strand and formed as a single core wire. In the case of this single core wire, a groove is formed on the entire outer peripheral surface.

The press-connecting wire 10 shown in FIG. 1 manufactured as described above is, as shown in FIGS.
As in the case of 7, it is press-connected to the press-connecting terminal 6 fixed inside the press-connecting connector 5. At the time of press-connecting with the press-connecting terminal 6, since the press-connecting wire 10 has high adhesion between the core wire 12 and the insulating coating 13, the insulating cover 13 is cut by the press-connecting blade of the press-connecting terminal 6 and cut off. Even so, slippage between the core wire 12 and the insulating coating material 13 does not occur, and it is possible to prevent a gap from being generated between the core wire 12 and the insulating coating material 13 and exposing the core wire 12. In addition, since the insulating coating material 4 tightly sandwiches both sides of the insulation displacement terminal 6, the insulation displacement material 6 and the insulation displacement wire 10
The connection strength with the connection can be increased to improve reliability.

Further, even when the press-connecting wire 10 pulled out from the press-connector 5 is pulled upward for the inspection of the press-contact strength, the degree of adhesion between the insulating coating material 13 and the core wire 12 is maintained. Since it is high, the electric wire 1 is not easily detached from the press contact terminal 6 as in the related art.

[0025]

As is apparent from the above description, the press-connecting wire according to the present invention has a large number of microgrooves formed on the outer peripheral surface of the core wire in contact with the insulating coating material. Is larger than in the case of a simple circular shape, and because of the unevenness, it is possible to make close contact with the insulating covering material so as to bite it, and thus it is possible to increase the fixing force between the core wire and the insulating covering material. Therefore, when this press-connecting wire is connected to the press-connecting terminal, the insulating coating material moves from the core wire, which has conventionally occurred, and a gap is generated between the press-connecting terminal and the cut end surface of the separated insulating coating material. Can be prevented. Therefore, since both sides of the press contact terminal can be sandwiched by the insulating covering material, the connection strength is increased, and the reliability of the electric connection in the case of press contact connection can be improved.

Further, in the method of manufacturing the insulation displacement wire according to the present invention, the core wire is passed through the groove forming die in a step prior to the step of coating the surface of the core wire serving as a conductor with an insulating coating material. Even without installing equipment, the surface roughness of the core wire can be increased very easily, and the adhesion of the core wire and the insulating coating material can be enhanced in the process of coating the insulating coating material thereafter. .

Furthermore, if the core wire is preheated in a step before coating the core wire with the insulating coating material, the core wire becomes soft and the resistance decreases, and the temperature difference between the two when the core wire is coated with the insulating coating material is small. Thus, the adhesion between the core wire and the insulating coating material can be further improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a press-connecting wire according to an embodiment of the present invention.

2A is a schematic view showing a method for manufacturing the press-connecting electric wire of FIG. 1, and FIG. 2B is a perspective view of a groove forming die.

FIG. 3 is a plan view showing a case where the press-connecting electric wire of FIG. 1 is press-connected to a press-connecting terminal in a press-connecting connector.

FIG. 4 is an enlarged perspective view of a main part of FIG.

FIG. 5 is a sectional view of a conventional electric wire.

FIG. 6 is a plan view when the conventional electric wire of FIG. 5 is press-connected to a press-connecting terminal in a press-connecting connector.

FIG. 7 is an enlarged perspective view of a main part of FIG. 6;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 wire 5 press-connecting connector 6 press-connecting terminal 10 press-connecting wire 11 element wire 11 a groove 12 core wire 13 insulating coating material 20 collective die 21 preheater 22 groove forming die 24 extruder

Claims (4)

[Claims] 1. A core wire serving as a conductor of an electric wire is covered with an insulating covering material made of an insulating resin, and the insulating covering material is cut by a press contact blade of a press contact terminal, and the press contact blade comes into contact with the core wire. A press-connecting electric wire to be electrically connected, wherein a number of minute grooves are provided on a surface of a portion of the core wire which comes into contact with the insulating coating material, and the insulating resin of the insulating coating material is closely attached to these grooves so as to bite. An electric wire for press-fitting, wherein the fixing force between a core wire and an insulating coating material is enhanced. 2. The groove is in the form of a streak extending in the axial direction, and the conductor is formed by twisting one core wire or a plurality of strands, and twisting the strands. The press-connecting wire according to claim 1, wherein the groove is provided at a position that becomes an outer peripheral surface in a twisted state. 3. A method for manufacturing a pressure welding wire in which an insulating resin is injected onto the outer periphery of a core wire serving as a conductor to form an insulating coating material on the outer periphery of the core wire, wherein the inner layer is formed in a step prior to the step of covering with the insulating resin. A core wire is passed through a die having a fine groove on the peripheral surface, a large number of fine grooves are provided on the outer peripheral surface of the core wire, and the insulating resin is coated on the contact surface with the core wire in the insulating resin coating step in a later step. A method of manufacturing a crimping electric wire that is closely attached so as to bite into a groove. 4. Prior to the step of coating with the insulating resin,
The method according to claim 3, wherein the core wire is preheated before or after passing through the die.