JP2002063980A - Welding method and equipment of electric wire having insulation cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To radically solve a problem resulting from generation of heat when an electrode and an electrode holder are separated. SOLUTION: For a method of bonding covered wires with terminals, a stacked body formed by bundling a plurality of covered wires covered with an insulation cover, and piling them on the connection terminals and conductive chips, is clamped between a pair of positive and negative electrodes, and heated by pressing and electric conduction, and the insulation covers of the piled body is fused and removed by heating, it is made a condition that a plurality of conduction paths are formed by preparing a plurality of electrodes for heating and fusing the body, and that the body is bonded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal in which a plurality of insulated wires (hereinafter referred to as "coated wires") wound in a coil shape, such as a motor, a relay coil, and a solenoid terminal, are connected to a connection terminal or a conductive chip. Also, the present invention relates to a method and an apparatus for welding an insulating film wire, which are useful when directly bonding to a plurality of other terminals by thermal caulking or spot welding.

[0002]

2. Description of the Related Art Conventionally, when an insulated wire having a coating such as an enameled wire or a resin is connected to a connection terminal, for example, Japanese Patent Application Laid-Open Nos. 6-218552 and 7-2564.
No. 64, JP-A-8-39264, JP-A-8-39264
The connection method described in JP 132245 and JP-A-8-264256 is known.

In the above-mentioned known technique, as shown in FIG. 4, an insulated wire W is superimposed on a connection terminal S or a conductive tip T or other metal fittings, and the superimposed workpiece is joined by utilizing resistance heating. In such a case, for example, a spot welder having an electrode structure as shown in FIG. 3 has been generally used. The upper electrode 34 and the lower electrode 35 shown in FIG.
6 and 37, and may be referred to as an upper chip or a lower chip. Further, the electrode holders 36, 3
Reference numeral 7 denotes a conical insertion portion which is fitted into the fitting portion of each of the chip holders 38 and 39 and is supported.

[0004] The electric current for causing the material to be welded to generate resistance heat is:
It flows directly from the upper tip to the lower tip via the workpiece. In this case, if the polarity is reversed, the current flows through the current path in the reverse direction, and the current path is connected to the terminal of the welding transformer as the current supply source.

Conventionally, the above-described energization method is generally used. As a result, a portion of the electrode tip having a higher electric resistance value than other portions generates heat, heats the workpiece, and further heats the workpiece. As a result of the increase in the resistance value due to the increase in temperature, self-heating of this portion is also added, so that the parts to be welded can finally be interconnected.

Conventionally, an upper electrode 34 and a lower electrode 35 which are in contact with a workpiece have a high electric resistance value represented by tungsten.
It is generally made of a metal having a high melting point.

[0007]

However, the conventional welding method has the following problems. (1) When the element wire (one thin bare wire) of the workpiece has an insulating film, the conventional connection method requires that the current flow directly from the upper chip to the workpiece to the lower chip, Since the object is covered with the insulating film, the current supply circuit is interrupted and heat cannot be generated, and the device does not function. In order for the welding machine to function with this type of work, a conductive material is wound around the work to be welded, and the upper and lower tips are pressed from above and below the wound material. An electric conduction path was formed through the conductive material. In this case, the joint is performed together with the conductive intermediate material, so that the amount of current is increased and the welding tact time is increased, and the material is wasted.

(2) Tungsten electrodes 34 and 3 of heating element
When the upper chip and the electrode holder are heated to a high temperature of 400 ° C. to 500 ° C., the brazing material is melted, and the endurance of the joined portion is established because the space between the electrode 5 and the electrode holders 36 and 37 is mainly joined by silver brazing. As a result, the junction is severely separated and the electrode itself is detached, causing a fatal problem of early consumption of the upper chip and the lower chip.

[0009]

Means for Solving the Problems In order to solve the above problems, a first aspect of the present invention is to provide a connection terminal or a conductive chip by bundling a plurality of coated wires whose surfaces are coated with an insulating coating. A welded lap formed by superimposing the welding wire is sandwiched between a pair of positive and negative electrodes and heated by applying pressure and current, thereby melting and removing the insulating film of the object to be welded, thereby connecting the coated wire and the terminal and the like. In the joining method, a plurality of electrodes for heating and melting the workpiece are prepared, and a plurality of current paths are formed by the electrodes to perform the joining.

3. A welding method according to claim 2, wherein at least one of said plurality of current paths causes at least two or more electrodes to come into contact with each other to generate heat, thereby producing an insulating film on said workpiece. Is required to constitute a heating circuit for dissolving and removing.

Further, in the welding method according to claim 3, one of the plurality of current-carrying paths causes at least two or more electrodes to come into contact with each other to cause the electrodes themselves to generate heat, thereby forming an insulating film on the workpiece. After melting and removing, the condition is that the welding circuit is switched to the other welding energizing circuit, whereby the welding force and welding current required for welding are supplied between the positive and negative electrodes to join the parts to be welded.

Further, according to a fourth aspect of the present invention, a lap welded article formed by bundling a plurality of coating wires covered with an insulating coating and superimposing the connecting wire on a connection terminal or a conductive chip or the like is formed by the fixed side electrode and the movable side electrode. In a welding device that sandwiches and applies a pressing force and a welding current required for welding between the electrodes to melt and remove an insulating film of the film wire and connect the film wire to the terminal and the like, the fixed side electrode and the movable Each of the side electrodes is composed of a pair of positive and negative electrodes, and the pair of positive and negative electrodes are disposed on the electrode holder with their electrode center lines inclined at an angle. , Thereby forming a heat generating portion at the tip of the electrode.

According to a fifth aspect of the present invention, there is provided a welding apparatus, wherein an intermediate electrode is arranged between the pair of positive and negative electrodes, and a tip of the intermediate electrode or the vicinity thereof is in local contact with a tip of the pair of positive and negative electrodes. Thereby, the tip of the intermediate electrode is intensively heated.

Further, in the welding apparatus according to the present invention, a bar-shaped electrode is arranged in the electrode holder in a V-shape, and the bar-shaped electrode is supported so as to be extendable in the electrode center line direction.
The electrode position is adjusted according to the amount of wear at the electrode tip.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view showing an embodiment of a welding electrode unit for carrying out an energizing method according to the present invention. FIG. 2 is a front view showing an embodiment for carrying out another energizing method of the present invention.

The basic structure of the above-mentioned electrode unit is divided into an upper electrode unit 1 and a lower electrode unit 2 as shown in FIG. The upper electrode unit 1 is arranged on a movable frame not shown in the figure and moves up and down. Further, the lower electrode unit 2 is arranged on the fixed frame. The upper electrode unit 1 and the lower electrode unit 2 have positive and negative electrode rods 3 and 5 and negative electrode and rod electrodes 4 and 6 which are vertically opposed to each other. It is firmly held by each electrode holder 8, 9. Note that a metal having a high electric resistance and a high melting point, such as tungsten or molybdenum, is used for this type of rod-shaped electrode.

Each of the rod electrodes 3, 4, 5, and 6 comes into contact with the upper and lower electrode holders 8 and 9 at a wide area, and is firmly attached by a fastening means such as a bolt (not shown). It has a structure capable of extending itself in the longitudinal direction of the electrode center lines a and b.

As shown in the figure, a pair of positive and negative rod electrodes 3 and 4 and rod electrodes 5 and 6 have an electrode center line a and b having a V-shaped inclination angle e that opens rightward and leftward. The holders 8, 9 are held in a state where some vertical surfaces of
It is supported by. The mutual contact point 10 of the rod-shaped electrodes 3 and 4 has a local area smaller than the plane cross-sectional area of the electrode tip E1 and increases the resistance value of the contact point 10 so that the contact point 10 is concentrated. Heat is generated by the current flowing through the electrode, and the temperature of the electrode end surface E1 in contact with the workpiece can be acceleratedly increased. The configuration described above has the same function as the upper and lower electrode units.

With the upper electrode unit opened, a connection terminal S is set on the electrode tip E2 of the lower electrode unit 2, and the work piece is welded so that the electrode tip E1 of the upper electrode unit 1 abuts on the film wire W side. Is set between the upper and lower electrodes. After the work is inserted into the welding position, the upper electrode unit 1 is lowered to bring the electrode tip E1 into contact with the coating wire W.

Thereafter, when a current is supplied to each energizing circuit formed by the positive and negative rod electrodes 3, 4, 5, and 6 of the upper and lower electrode units 1 and 2, the current is applied to the V-shaped positive and negative rod electrodes. Flows through the contact point 10 to the work, and the electrode surface in contact with the work is heated at an accelerated rate, and this heat is transmitted to the connection terminal S and the film wire W to thermally destroy the insulating film.

After the insulating coating of the film wire is dissolved in this way, the current-carrying circuit up to now is cut off, and the positive and negative (−) side bar electrodes of the upper electrode unit 1 are temporarily connected to one of the + electrodes by another power supply.
If the energizing circuit is switched to the + side between the positive and negative electrodes of the lower electrode unit 2 to the other − side, the rod electrode (+ side) of the upper electrode unit 1, the workpiece, and the lower electrode unit 2 A direct energization circuit for the rod-shaped electrode (-side) is configured.
Therefore, a necessary welding pressure is generated at the electrode tip E1 of the upper electrode unit 1, and a welding current can be directly supplied between the upper and lower electrodes to directly heat and press-weld the workpiece.

When the welding is completed, the upper electrode unit 1 is opened, a new work is taken in and out at a predetermined position, and the welding cycle is repeated in the same manner.

FIG. 2 shows another embodiment of the present invention. In this case, as shown in the embodiment of the figure, the upper and lower electrode units 1 and 2 have a rod-shaped intermediate electrode 11 in the middle of the pair of positive and negative rod electrodes 3 and 4 and an interposed insulating material 12 between the positive and negative electrodes. The upper and lower electrode holders 8 and 9 are arranged separately. In order to form a heat generating portion at the tip of the intermediate electrode 11, the tip of the pair of positive and negative rod-shaped electrodes arranged in a V-shape with respect to the intermediate electrode 11 has a structure in which they are in local contact with each other.

The current flows from the positive pole electrode 3 to the intermediate electrode 11 through the contact point 10 and to the negative pole electrode 4 through the contact point 13. As a result, heat is intensively generated in the vicinity of the intermediate electrode 11 in contact with the workpiece, and the insulating film of the workpiece is thermally destroyed.

After the insulating film is dissolved and removed by the heat generation, the heating circuit is cut off in the same manner as in the above-described embodiment, and the positive and negative rod electrodes of the upper electrode unit 1 are temporarily connected by another power source. If the energizing circuit is switched to the other side of the rod electrode between the positive and negative sides of the lower electrode unit 2, the + side intermediate electrode 11 of the upper electrode unit 1,
A direct energization circuit is formed between the lower electrode unit and the negative intermediate electrode 14.

Therefore, by applying a welding force between the upper electrodes and supplying a welding current, the workpiece can be directly heated and pressed.

[0027]

As described above, according to the method of the present invention, a terminal in which a plurality of coiled insulated wires such as a motor, a relay coil and a solenoid terminal are bundled is connected to a connection terminal. Alternatively, when directly set on a mating plate such as a conductive chip and bonded by thermal caulking or spot welding, the electrode tip was heated at an accelerated rate through a plurality of conducting circuits, and the insulating film was directly dissolved and removed by the heating. Later, the work can be switched to direct energization and joined.
Compared with the conventional wire / terminal joining method, there is no need to configure an electrical conduction path through a conductive material that is not directly related to the workpiece, so that the conductive material can be omitted and welding tact time can be reduced. .

According to the apparatus of the present invention, the rod-shaped electrode can make electrical / mechanical contact with the electrode holder over a wide area.
The electrode holder can be mechanically tightened. Compared to the conventional electrode device, in which the electrode and the electrode holder are joined by brazing, the problem of heat-caused troubles such as separation of the electrode and the electrode holder can be eliminated. Can achieve a strategic solution.
Further, it is possible to provide an inexpensive electrode unit which is free from special work requiring experience and skill of brazing.

Further, according to the apparatus of the present invention, by adding a mechanism capable of extending the rod-shaped electrode in the direction of the center line of the electrode axis to the electrode holder, it is possible to easily adjust the amount of wear of the electrode tip on the side in contact with the workpiece. The electrode position can be adjusted, the shape of the electrode tip can be easily modified, and the life of the electrode can be extended to various stages even as a consumable electrode used repeatedly.

[Brief description of the drawings]

FIG. 1 is a schematic view of a welding electrode unit showing an embodiment for carrying out the present invention.

FIG. 2 is a schematic view showing another embodiment for carrying out the present invention.

FIG. 3 is a cross-sectional view showing a structural example of a conventional resistance welding electrode device.

FIG. 4 is an external view of a work for joining an insulating film electric wire and a connection terminal or a conductive chip.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Upper electrode unit, 2 Lower electrode unit, 3 Positive electrode rod 4 Negative electrode rod, 5 Positive electrode rod, 6 Negative electrode rod 7 Insulating material, 8 Upper electrode holder, 9 Lower electrode holder, 1
0 contact part 11 upper intermediate electrode, 12 insulating material, 13 contact part, 14
Lower intermediate electrode S Connection terminal, W Insulated wire

Claims (6)

[Claims] 1. A lap welded article formed by binding a plurality of coated wires having the surface of an electric wire covered with an insulating film and superimposing the wires on a connection terminal or a conductive chip or the like, sandwiching the lap weld between a pair of positive and negative electrodes, and applying pressure. In a method of connecting the coating wire to the terminal and the like by melting the insulating film of the object to be welded by energizing and heating, a plurality of electrodes for heating and melting the object to be welded are prepared. A method for welding an insulated wire, wherein a plurality of current paths are formed and the workpieces are joined. 2. The welding method according to claim 1, wherein at least one of the plurality of current paths causes at least two or more electrodes to contact each other to generate heat, thereby insulating the workpiece. A method for welding an insulated wire, provided that a heating circuit for dissolving and removing the film is formed. 3. The welding method according to claim 1, wherein at least one of the plurality of current paths causes at least two or more electrodes to come into contact with each other to cause the electrodes themselves to generate heat, thereby causing the workpiece to be welded. After dissolving and removing the insulating film, the condition is that the welding circuit is switched to the other welding energizing circuit, whereby the welding force and welding current required for welding are supplied between the positive and negative electrodes to join the parts to be welded. Welding method for insulated wire. 4. A lap weld formed by bundling a plurality of film wires covered with an insulating film and superimposing them on a connection terminal or a conductive chip or the like, sandwiching the lap weld between the fixed side electrode and the movable side electrode, and In a welding apparatus for supplying a pressing force and a welding current necessary for welding to melt and remove the insulating film of the film wire and connecting the film wire to the terminal and the like, the fixed side electrode and the movable side electrode are respectively positive and negative. The pair of positive and negative electrodes are arranged on an electrode holder with their electrode center lines at an inclined angle to each other;
In addition, the tip of the pair of positive and negative electrodes is in contact with each other, thereby forming a heat-generating portion at the tip of the electrode. 5. The welding apparatus according to claim 4, wherein an intermediate electrode is disposed between the pair of positive and negative electrodes, and a tip of the intermediate electrode or its vicinity is in local contact with the tips of the pair of positive and negative electrodes. , Whereby the tip of the intermediate electrode is intensively heated by the insulating film wire. 6. A welding apparatus according to claim 4, wherein a rod-shaped electrode is disposed in the electrode holder in a V-shape, and the rod-shaped electrode is supported so as to be extendable in the direction of the electrode center line. An electrode position adjusting device according to the amount of wear of a wire.