JP2001096372A - Method of resistance welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of resistance welding wherein electrode pressurizing force smaller than weight of a supply mechanism for electrode pressurizing force can be obtained and thermo-compression bonding or spot welding of workpieces can be done by reducing or increasing the electrode pressurizing force in welding. SOLUTION: The method comprises the steps of moving an electrode to the workpieces, detecting that the electrode abuts on the workpieces, pressurizing the workpieces, energizing the electrode, measuring a displacement quality of thickness of the workpieces in welding, reducing or increasing the electrode pressurizing force in welding when the displacement quality of the workpieces reaches the given value, stopping energizing the electrode after a specific time and making the workpieces held by the reduced or increased electrode pressurizing force after the welding expiration. The thermo-compression bonding or spot welding is done by the method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resistance welding method for performing thermocompression bonding or spot welding of a very small conductor wire or a conductor component to a terminal portion of an electronic component or various sensors with a minimal electrode pressing force.

[0002]

2. Description of the Related Art Conventionally, as a method of fixing a conductor wire or a conductor component (hereinafter, collectively simply referred to as a workpiece) to a terminal portion of an electronic component or various sensors, the workpiece is pressurized with an electrode. There are a thermocompression bonding method in which a welding current is applied while the electrodes are heated to a high temperature to press the objects to be welded together by the heat, and a spot welding method in which the welding current is applied by pressing the objects to be welded between the electrodes. Hereinafter, these methods are collectively referred to simply as resistance welding.

[0003] In resistance welding when the conductor wire to be welded is a fine wire of, for example, several tens of microns or the conductor component is of a very small size, the electrode pressing force must be minimized.
As a countermeasure, the mechanism for obtaining the electrode pressing force has been devised on the hardware side such as minimizing the size and reducing the weight.

[0004]

In the conventional method for reducing the electrode pressing force supply mechanism to be as small and light as possible, the weight of the electrode pressing force supply mechanism itself is added to the electrode pressing force. The electrode pressing force smaller than the weight of the pressure supply mechanism cannot be obtained, and the electrode pressing method, the thickness control of the workpiece to be welded during welding, or the temperature control of the electrode also affects the welding quality, so the extremely small thin wire In fact, it is impossible to perform resistance welding of a workpiece to be welded to a conductor part.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a resistance welding method which enables resistance welding of extremely small wires or conductor parts.

[0006]

A first means of the present invention is as follows.
A step of approaching and detaching the electrode from and to the workpiece, a step of detecting that the electrode has contacted the workpiece, a step of pressing the workpiece with the electrode, and a step of applying a welding current to the electrode, Measuring the displacement of the thickness of the workpiece during welding; reducing or increasing the pressure of the electrode when the displacement of the workpiece during welding reaches a predetermined value; A step of measuring a welding end delay time for stopping the energization after a certain time when the displacement amount of the workpiece reaches a predetermined value,
A step of maintaining the pressurization at the above-mentioned reduced pressure or increased pressure for a predetermined time by the electrode after the welding is completed.

[0007] A second means of the present invention includes a step of moving the electrode toward and away from the workpiece, a step of detecting that the electrode abuts on the workpiece, and a step of pressing the electrode with the workpiece. Applying a welding current to the electrode, measuring the thickness displacement of the workpiece during welding, and applying pressure to the electrode when the temperature of the electrode during welding reaches a predetermined value. A step of reducing or increasing the pressure; a step of measuring a welding end delay time for stopping the energization after a certain time when the temperature of the electrode during welding reaches a predetermined value; and And maintaining the pressurization at the reduced pressure or the increased pressure.

[0008] A third means of the present invention comprises a step of inputting an urging force to the workpiece as an electrode pressing force to the operation unit, a step of calculating the electrode pressing force by the control unit into a moving amount of the driving means, Obtaining an electrode pressing force by expansion and contraction of an elastic body as an urging means connected to the driving means.

In a fourth aspect of the present invention, in the step of pressing the workpiece by the electrode, the contact weight of the electrode with the workpiece when the electrode comes into contact with the workpiece is determined by an electrode pressing force supply mechanism. It is characterized in that an electrode pressing force smaller than the weight can be obtained.

In a fifth aspect of the present invention, in the step of pressurizing the work to be welded by the electrode, the contact weight of the electrode pressing force supply mechanism for the work to be welded when the electrode comes into contact with the work to be welded is the same. From the value, or at least a step of inputting a value smaller than the value as an electrode pressing force correction value to the operation unit, and from the value obtained by inputting the urging force to the workpiece to the operation unit as the electrode pressing force,
Calculating the electrode pressing force obtained by subtracting the electrode pressing correction value into the moving amount of the driving means.

According to a sixth aspect of the present invention, an elastic body as an urging means for obtaining an electrode pressing force is replaced and changed. The step of inputting the correction value to the operation unit can obtain an electrode pressing force according to the type of the workpiece.

[0012] A seventh means of the present invention is a step in which the electrode pressurizes the work to be welded, and the driving means is driven in the minus direction during welding to reduce the pressure on the electrode, or the drive means is driven in the plus direction. The method further comprises the steps of: increasing the pressure of the electrode to increase the pressure of the electrode; and inputting the lifting / lowering speed of the electrode together with the electrode pressing force to the operation unit.

The eighth means of the present invention is characterized in that the control means stores a position where the tip of the electrode abuts on the work to be welded, and a step of displaying the position as a digital coordinate value. And

According to a ninth aspect of the present invention, when ON is selected in the "ON-OFF" selecting step of the workpiece detection and displacement measuring means, the sensor of the workpiece detection and displacement measuring means becomes effective. If the user selects OFF, the sensor becomes invalid and the preset position input means inputs arbitrary workpiece detection position data, and the input position is set to the same position as the position in contact with the workpiece. And a step of storing as deemed.

[0015] A tenth means of the present invention is that, when "ON" is selected in the "ON-OFF" selection step of the workpiece detection and displacement amount measuring means, the preset position input means speeds down the electrode from high speed to low speed. A step of inputting position data to be switched, a step of positioning the driving means from the start of the high speed descent of the electrode to the switching to the low speed, and a driving means from the low descent to the detection of the work to be welded at an arbitrary position. And a step of positioning the drive means until the electrode is raised to the origin after welding is detected after the workpiece is detected.

According to an eleventh aspect of the present invention, when "OFF" is selected in the "ON-OFF" selecting step of the workpiece detection and displacement amount measuring means, it is regarded as the same position as the position in contact with the workpiece. Displaying the stored position as digital coordinate values at all times.

In a twelfth aspect of the present invention, when "OFF" is selected in the "ON-OFF" selection step of the workpiece detection / displacement amount measuring means, an arbitrary workpiece detection position data is inputted by the preset position input means. Inputting a position at which the electrode descent is switched from high speed to low speed at a position in front of the input position based on the input position.

According to a thirteenth aspect of the present invention, when the thickness of the workpiece to be welded is small, that is, when the displacement is large, the displacement of the thickness of the workpiece is preset. Has an automatic pressure increasing / decreasing step of automatically increasing the electrode pressure when the thickness of the workpiece to be welded during welding is large, that is, when the amount of displacement is small, automatically. I do.

A fourteenth means of the present invention is characterized in that at the beginning of the step of applying a welding current to the electrode, a welding start delay section for delaying the application of electricity is provided.

A fifteenth aspect of the present invention is characterized in that the apparatus has a pressure-reducing or pressure-increasing start delay section for delaying the application of pressure to the pressure-reducing or pressure-increasing electrode during welding.

The sixteenth means of the present invention is characterized in that after the welding is completed, the pressure of the electrode is reduced or increased, and a holding section for holding the work to be welded for a certain period of time is provided.

According to a seventeenth aspect of the present invention, an electrode pressing force value is digitalized in a section from when the electrode comes into contact with the work to be welded to when the welding is completed and the pressure of the electrode is reduced or increased. The upper and lower limits of the electrode pressure values for the process of displaying numerical values, and when the electrode contacts the workpiece, when the electrode is pressurized, and when the pressure of the electrode is reduced or increased. And a step of outputting an abnormal signal if the electrode pressing force value is out of the range, and performing an abnormal alarm after the operation of the resistance welding apparatus is completed.

The eighteenth means of the present invention comprises a step of counting the number of times of electrode polishing by an electrode polishing preset counter each time a workpiece to be welded is produced, and a step of counting the number of times the electrode polishing preset counter reaches a preset set value. Automatically polishing the electrode by a polishing apparatus.

[0024]

According to a first aspect of the present invention, a step of moving an electrode toward and away from an object to be welded, a step of detecting contact of the electrode with the object to be welded, A step of applying a welding current to the electrodes, a step of applying a welding current to the electrodes, a step of measuring the displacement of the thickness of the workpiece during welding, and a step of measuring the displacement of the workpiece during welding to a predetermined value. A step of reducing or increasing the pressurization of the electrode when it reaches, and a step of measuring a welding end delay time for stopping the energization after a certain time when the displacement of the workpiece during welding reaches a predetermined value. ,
After the welding is completed, for a certain period of time the workpiece to be welded by the electrode, and the step of maintaining the pressurization at the reduced pressure or increased pressure,
The effect is obtained that a high quality welded object can be obtained.

The second means includes: a step of moving the electrode toward and away from the workpiece; a step of detecting that the electrode is in contact with the workpiece; a step of pressing the workpiece with the electrode; Applying a welding current to the workpiece, measuring the thickness displacement of the workpiece during welding, and reducing or increasing the pressure of the electrode when the temperature of the electrode during welding reaches a predetermined value. Pressurizing, a step of measuring a welding end delay time in which energization is stopped after a certain time when the temperature of the electrode during welding reaches a predetermined value, and pressing the work piece by the electrode for a certain time after the welding is completed. And the step of maintaining the pressure at the above-mentioned reduced pressure or increased pressure, so that the effect of obtaining a high quality welding result of the workpiece can be obtained.

The third means includes a step of inputting the urging force to the workpiece as an electrode pressing force to the operation unit, a step of calculating the electrode pressing force by the control unit as a moving amount of the driving means, and a step of Since the method includes the step of obtaining the electrode pressing force by expansion and contraction of the elastic body as the connected urging means, it is possible to digitally manage the setting of the electrode pressing force and to obtain the operation of obtaining the minimum electrode pressing force.

The fourth means is that, in the step of pressing the workpiece with the electrode, the contact weight of the electrode against the workpiece when the electrode contacts the workpiece is greater than the weight of the electrode pressing force supply mechanism. Since a small electrode pressing force can be obtained, an effect that resistance welding of an extremely small thin wire or a conductor component can be performed is obtained.

The fifth means is that, in the step of pressing the workpiece with the electrode, the same value as the contact weight of the electrode pressing force supply mechanism with respect to the workpiece when the electrode contacts the workpiece,
Or at least a step of inputting a value smaller than the value as an electrode pressing force correction value to the operation unit, and the electrode pressing force correction from the value input as the electrode pressing force to the workpiece to the operation unit. Calculating the electrode pressing force from which the value has been subtracted into the amount of movement of the drive means, so that the value obtained by inputting the urging force to the workpiece into the operating section as the electrode pressing force is directly used as the electrode pressing force value. The effect that the object can be pressurized can be obtained.

The sixth means is to change the elastic body as the urging means for obtaining the electrode pressing force by changing the part number of the elastic body, the pressure constant for the expansion and contraction of the elastic body, and the electrode pressing force. By the step of inputting the pressure correction value to the operation unit, an operation that an electrode pressing force corresponding to the type of the workpiece can be obtained.

The seventh means is a step in which the electrode presses the workpiece, and a step in which the driving means is driven in the minus direction during welding to reduce the pressure of the electrode, or the method in which the driving means is driven in the plus direction. Since the method includes the step of increasing the pressurizing force of the electrode and the step of inputting the electrode lifting and lowering speed to the operation unit together with the electrode pressing force, an operation of digitally managing the setting of the electrode pressing force is obtained.

The eighth means includes a step of storing, in the control unit, a position where the tip of the electrode is in contact with the workpiece, and a step of displaying the position in digital coordinate values. The effect that the position in contact with the welded object can be digitally managed can be obtained.

The ninth means is that when “ON” is selected in the “ON-OFF” selection step of the workpiece detection and displacement amount measuring means,
The sensor of the work piece detection and displacement amount measurement means becomes effective,
If "OFF" is selected, the sensor becomes invalid and the preset position input means inputs arbitrary workpiece detection position data, and the input position is regarded as the same position as the position in contact with the workpiece. And the step of storing the information, the operation can be obtained in a resistance welding apparatus in the case where there is no means for detecting and measuring the amount of displacement of the workpiece. First
0 means “input to
When "On" is selected in the "Off" selection step, a step of inputting position data for switching the electrode descent speed from high speed to low speed by the preset position input means, and a driving means until the electrode is switched from low speed to low speed after the start of high speed descent. The step of positioning operation, the step of jog operation of the driving means from the low speed descent to the detection of an object at any position, and the step of detecting the object to be welded until the welding is completed and the electrode rises to the origin. Since the method includes the step of positioning the drive means, the operation time of the resistance welding apparatus can be shortened.

In the eleventh means, when "OFF" is selected in the "ON-OFF" selection step of the workpiece detection / displacement measuring means, the workpiece is stored as being in the same position as the position in contact with the workpiece. And a step of always displaying the position in digital coordinate values, so that even in a resistance welding apparatus in which there is no workpiece detection and displacement amount measuring means, the position is regarded as the same as the position in contact with the workpiece and stored. The effect that digital management can always be performed at the position where the camera is located can be obtained.

The twelfth means is that, when "OFF" is selected in the "ON-OFF" selection step of the workpiece detection and displacement amount measuring means, the position at which arbitrary workpiece detection position data is inputted by the preset position input means. And a step of inputting a position at which the electrode descent is switched from high speed to low speed at a position in front of the position, so that even in a resistance welding apparatus having no workpiece detection and displacement amount measuring means, The effect of shortening the operation time of the resistance welding device can be obtained.

According to a thirteenth aspect, the thirteenth means of the present invention, which has been set in advance, is arranged such that a predetermined displacement amount of the thickness of the workpiece is changed with respect to a predetermined displacement amount of the workpiece during welding. When the thickness is small, that is, when the displacement is large, the electrode pressure is automatically reduced,
When the thickness of the workpiece during welding is large, that is, when the amount of displacement is small, there is an automatic pressure increasing step that automatically increases the electrode pressure, so that the effect of stabilizing the welding result of the workpiece is obtained. Can be

Since the fourteenth means has a welding start delay section for delaying the application of electricity at the beginning of the step of applying the welding current to the electrode, the effect of stabilizing the welding result of the workpiece is obtained.

The fifteenth means has a pressure reduction or pressure increase start delay section in which the pressure of the electrode is delayed to a pressure reduction or pressure increase during welding, so that the effect of stabilizing the welding result of the workpiece can be obtained.

The sixteenth means has a holding section for holding the object to be welded for a certain period of time at a reduced or increased pressure of the electrode after the welding is completed, so that the welding result of the object to be welded is stabilized. can get.

The seventeenth means is to display the electrode pressing force digitally in a section from the time when the electrode comes into contact with the work to be welded to the time when the welding is completed and the pressure applied to the electrode is reduced or increased. And setting the upper and lower limits of the electrode pressing force value when the electrode comes into contact with the workpiece, when the electrode is pressurized, and when the pressure of the electrode is reduced or increased. A step of outputting an abnormal signal if the electrode pressure value is out of the range and issuing an alarm after the operation of the resistance welding apparatus is completed, so that an operation of digitally managing the electrode pressure can be obtained.

The eighteenth means includes a step of counting the number of times of electrode polishing by an electrode polishing preset counter each time a workpiece is produced, and an operation of the electrode polishing apparatus after the electrode polishing preset counter reaches a preset set value. Since the step of automatically polishing the electrode is provided, the effect of stabilizing the quality of the welding result of the workpiece and extending the life of the electrode is obtained.

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS. 1, 2 and 3. FIG. FIG. 1 is a schematic view of the resistance welding method, in which the control unit 18 and the operation unit 19 control the pressure of the workpieces 12a and 12b by 3 and apply a welding current by the welding 23 to perform the resistance welding. FIG. 3 is a perspective view of a resistance welding apparatus using the resistance welding method of the present invention, and FIG. 3 is a welding operation diagram.

The configuration of a perspective view of the resistance welding apparatus shown in FIG. 2 will be described. The upper slider 1 is driven in the direction of the workpieces 12a and 12b, and the lower slider is slidably held with respect to the upper slider 1. The slider 2, an electrode 3 attached to the lower slider 2 and brought into contact with the workpieces 12 a and 12 b, and the lower slider 2 provided between the upper slider 1 and the lower slider 2 are connected to the workpieces 12 a and 12 b.
A biasing means 4 for biasing the lower slider 2, a locking portion 5 provided on the lower slider 2, and a contact with the locking portion 5 until the electrode 3 comes into contact with the workpieces 12a and 12b when the lower slider 2 moves. Further, an urging force control means 6 for urging the lower slider 2 in a direction opposite to the workpieces 12a and 12b is provided.

The operation of the schematic diagram of the resistance welding method of FIG. 1 and the perspective view of the resistance welding apparatus of FIG. 2 will be described with reference to the welding operation diagram of FIG. The outline of the operation process in FIG. 3 includes an electrode descending section L1, an electrode pressurizing and upsetting section L2 (decreasing or increasing the electrode pressurizing is referred to as forging pressure), a forging pressure section L3, and an electrode rising section L4. First, in the electrode descending section L1 in FIG. 3, the electrode 3 in FIG. 3 is at the origin P0 by the electrode moving step 101 in FIG.
When 3 rotates in the normal rotation direction, the screw 14 is rotated by the motor 13 and screwed to the screw 14, and is driven in the direction of the workpieces 12 a and 12 b by the screwing portion 15 held by the upper slider 1. The upper slider 1, the lower slider 2 slidably held by the upper slider 1 with respect to the upper slider 1, and the electrode 3 attached to the lower slider 2 in the electrode positioning operation step 124 of FIG. It descends at a high speed from the point of origin P0 in FIG.
).

3 by the electrode speed switching step 123 of FIG.
When the electrode 3 reaches the low-speed point P1, the electrode 3 descends at a low speed from the low-speed point P1 to the workpiece contact point P2 in the electrode jog operation step 125 in FIG. ). Lowering at a low speed can deform the workpiece,
This is so as not to cause any damage.

Examples of the elastic body 4 as the urging means 4 include a driving means 13 such as a coil spring, a plate spring, or an elastic rubber.
Examples of the motor 13 include a servo motor, a stepping motor, an inverter motor, and an induction motor.

Until the electrode 3 in FIG. 3 reaches the point P2 from the point of origin P0 to the point of contact P2, the upper slider 1 is lowered by the slip-off preventing unit 7 connecting the upper slider 1 and the lower slider 2. For example, the lower slider 2 also descends. When the electrode 3 comes into contact with the workpieces 12a and 12b in the workpiece contact detection step 102 in FIG. 1, the lower slider 2 descends while the lower slider 2 remains in contact with the workpieces 12a and 12b. Instead, the locking portion 5 contacts the contact end 8 of the lever portion 24.

When the motor 13 of the driving means 13 rotates forward, only the upper slider 1 is lowered, and the slip-off preventing portion 7 connecting the upper slider 1 and the lower slider 2 is formed.
Is disengaged from the upper slider 1, and only the upper slider 1 descends, and the slip-out preventing portion 7 presses the displacement sensor 16 which is the workpiece detection means 27. Then, the displacement sensor 16 operates to transmit the signal to the displacement measuring unit 17. Accordingly, the displacement measuring unit 17 calculates the displacement and calculates the electrode 3
Has reached the contact point P2 of the workpiece to be welded in FIG. 3 (in FIG. 3), which means that the workpieces 12a and 12b have been detected. The point P2 of FIG. 3 where the electrode 3 abuts on the workpieces 12a and 12b is stored in the workpiece position storage step 119 in FIG. At 120, the position is displayed in digital coordinate values.

Next, the electrode pressurization and upsetting section L2 of FIG.
In FIG. 2, the lever 24 as the urging force control means 6 in FIG.
Is a contact end 8 to be brought into contact with the locking portion 5, and a workpiece 12a,
A weight 11 connected to the biasing end 9 for biasing in the direction 12b, and a fulcrum 10 between the contacting end 8, the biasing end 9 and the weight 11, the electrode 3, the lower slider 2, and the slip-off preventing portion. 7 is urged by the urging force control means 6 in a direction opposite to the workpieces 12a and 12b.

For example, if the total weight of the electrode 3, the lower slider 2, and the slip-off preventing portion 7 is 300 grams, this is W1, and if the weight by the biasing force control means 6 is 300 grams, this is W2. Is W3. When this is represented by an equation, W1−W2 = W3, and when a numerical value is substituted, 300 is obtained.
Grams-300 grams = 0 grams.

The reason is that the electrodes 3 are connected to the workpieces 12a and 12b.
Means the initial weight, ie, the amount of pressure applied, is 0 grams.

If the weight 1 connected on the biasing end 9
If the weight of 1 is changed to 250 grams, W1-W2 =
When W3 is substituted, 300 grams-250 grams =
50 grams.

The reason is that the electrodes 3 are connected to the workpieces 12a and 12b.
Means that the initial weight, ie, the pressing force, is 50 grams. By changing the weight of the weight 11, the initial weight, that is, the initial value of the pressing force can be changed. From this state, the motor 13 as the driving means 13 rotates in the forward rotation direction, and the workpieces 12a,
The pressing force applied in the direction 12b
Even if the motor 13 rotates in the forward direction, the lower slider 2 stops without descending in the direction of the workpieces 12a and 12b because the lower slider 2 remains in contact with the workpieces 12a and 12b. And only the upper slider 1 descends in the direction of the workpieces 12a and 12b.

That is, the pressing force of the electrode 3 applied to the workpieces 12a and 12b is only the expansion and contraction of the elastic body 4 which is the urging means 4, and the electrode 3, the lower slider 2 and the disengagement preventing portion 7
Is not applied to the workpieces 12a and 12b. Further, the upper slider 1 descends, but the lower slider 2 does not descend while the lower slider 2 remains in contact with the workpieces 12a and 12b, and the lower slider 2 does not descend as shown in FIG. The constant of the elastic body 4 (1
The pressing force of the elastic body 4 per mm) is proportional to the moving distance of the upper slider 1, and the workpieces 12a,
The pressing force in contact with 12b increases proportionally.

The electrode 3 is connected to the contact point P of the work to be welded in FIG.
After an electrode pressing start delay time (including zero) has elapsed from two points, an electrode pressing force input step 111 in the operation unit 19 in FIG.
The electrode pressure is applied in the direction of the workpieces 12a and 12b according to the input values of the electrode pressing force and the pressing speed. This electrode pressing force is calculated as the amount of movement of the motor 13 as the driving means 13 in FIG. 2 in the driving means movement calculating step 112 in FIG. For example,
The constant of the elastic body 4 is 0.1 kg / mm (1 mm for the elastic body 4
When it shrinks, the pressing force becomes 100 grams and the elastic body 4 is 2m
m, the pressing force becomes 200 grams), and the driving means 13 when the electrode pressing force is input as 150 grams
The calculation of the moving amount of the motor 13 is: electrode pressing force ÷ constant of the elastic body 4 = moving distance, 0.15 ÷ 0.1 kg / mm =
1.5 mm, and the upper slider 1 is lowered by 1.5 mm. When the upper slider 1 is lowered by 1.5 mm, the elastic body 4 is contracted by 1.5 mm.
At 13, the electrode pressure becomes 150 g and the workpiece 1
2a and 12b will be pressurized.

When the electrode pressurization elapses, a welding start delay time (including zero) elapses in the electrode energizing step 104 in FIG. 1, and the welding power source 23 in FIG. 1 is activated to start welding. As a result, a welding current flows through the electrode 3 and the workpieces 12a and 12b
Are thermocompression bonded or spot welded. In the displacement measuring step 105 of FIG. 1, the displacement of the thickness of the workpieces 12a and 12b is measured by the displacement measuring means 27 during welding. As the displacement amount measuring means 27, the detachment preventing unit 7 linked to the elevation of the electrode 3
A displacement sensor 16 held by the upper slider 1 for detecting a gap between the upper slider 1 and a displacement sensor 16 for calculating a signal of the displacement sensor 16 into a displacement.

In the step 121 for measuring the amount of contact and displacement of the workpiece to be welded shown in FIG. The displacement signal from the displacement sensor 16 when the electrode 3 contacts the objects 12a and 12b and the displacement signal from the displacement sensor 16 when the electrode 3 contacts the workpieces 12a and 12b being welded are displaced. The quantity measuring unit 17 separates and outputs.

When the electrode pressurizing and upsetting section L2 of FIG. 3 is completed, the work piece 12 is welded during the welding in the forging section L3.
The displacement amounts of the thicknesses a and 12b are the displacement amount measuring units 17 at the point P3 at which the electrode pressing force starts decreasing or increasing the pressure in FIG.
(FIG. 3), a displacement amount signal is input to the control unit 18, and the forging start delay time (for which zero is also applied) for forging the electrode pressing force from the pressure reduction start point or the pressure increase start point P3 of the electrode pressing force. 1) and the displacement amount welding end delay step 107 in FIG.
, The welding end delay time (including zero) is counted. After the elapse of the forging start delay time, when the forging pressure applied to the displacement amount forging step 106 in the operation unit 19 in FIG.
At the forging speed, the upper slider 1 rises to the pressure reduction point P4 (FIG. 3), and the electrode pressing force is reduced.

If the forging pressure applied to the displacement forging step 106 in the operation section 19 of FIG. 1 is larger than the electrode pressing value, the pressure is increased to the pressure increasing point P4 'in FIG. , The upper slider 1 descends to the pressure increasing point P4 '(FIG. 3), and the electrode pressing force increases. When the electrode 3 rises, the motor 13 is reversely rotated in the negative direction,
, The motor 13 is positively rotated in the positive direction. Then, when the welding end delay time has elapsed, the welding power source 23 is turned off and the welding is stopped.

The purpose of forging during welding is to reduce or increase the melting state of the welded members 12a and 12b during thermocompression bonding or spot welding, so that the work to be welded is started at the pressure reduction start point or the pressure increase start point P3. When the melting is excessive, the excessive melting is reduced by reducing the pressure, and when the melting is insufficient, the insufficient melting is improved by reducing the pressure to improve the quality.

After the elapse of the forging section in FIG. 3, the holding time for holding the electrode 3 is counted, and the workpieces 12a, 12a,
12b is held under pressure by forging. After the elapse of the holding time, in the electrode ascending section L4, the electrode 3 moves to the decompression point P4.
The electrode 3 rises at a low speed from the point or the pressure increasing point P4 to the low speed point P1 (in FIG. 3), and at the low speed point P1 (FIG. 3), the electrode 3 rises at a high speed to reach the origin P0 point and reach the electrode P0. 3
Stops rising. (~ In FIG. 3).

(Embodiment 2) After the electrode pressurizing and upsetting section L2 in FIG. 3 is completed, the temperature of the electrode 3 in FIG. Point P3
When output from the temperature measuring unit 21 at the point (of FIG. 3), the electrode temperature forging step 109 in the control unit 18 of FIG.
The electrode temperature signal is input at the point, and the electrode pressing force is forged from the pressure reducing point or the pressure increasing point P3 of the electrode pressing force in FIG.
The forging start delay time (including zero) and the welding end delay time (including zero) of FIG. 3 are counted in the electrode temperature welding end delay step 110 of FIG. When the forging start delay time in FIG. 3 elapses, when the forging pressure applied to the electrode temperature forging step 109 in the operation unit 19 in FIG. 1 is smaller than the electrode pressing value, the pressure becomes the decompression point P4, and the electrode 3 becomes the forging speed. Then, the upper slider 1 in FIG. 2 rises to the pressure reduction point P4 (in FIG. 3) (forging pressure section L3 in FIG. 3), and the electrode pressing force is reduced.

If the forging pressure applied to the electrode temperature forging step 109 in the operating section 19 in FIG. 1 is larger than the electrode pressing value, the driving means electrode forging step 117 in FIG. The pressure point P4 'is reached, and the upper slider 1 is lowered at the forging speed to the pressure increasing point P4' (FIG. 3) (forging pressure section L5 in FIG. 3), and the electrode pressing force is increased. FIG.
When the electrode 3 of FIG. 2 rises, the motor 13 is reversely rotated in the negative direction, and when the electrode 3 of FIG.
3 is positively rotated in the plus direction. When the welding end delay time in FIG. 3 elapses, the welding power source 23 in FIG.
F stops welding.

The purpose of forging during welding is the same as in the first embodiment.
This is because the quality is improved by reducing or increasing the pressure of the molten state of 2a and 12b.

(Embodiment 3) When the electrode pressurizing and upsetting section L2 of FIG. 3 is completed, the displacement of the thickness of the workpieces 12a and 12b during welding in the forging section L3 is reduced by the electrode pressing force of FIG. When the displacement amount is output from the displacement measuring unit 17 at the pressure reduction start point or the pressure increase start point P3 (see FIG. 3), the displacement amount signal is input to the control unit 18 and the pressure reduction start point or the pressure increase start of the electrode pressing force is started. A forging start delay time (including zero) for forging the electrode pressing force from point P3 and a welding end delay time (including zero) in the displacement amount welding end delay step 107 in FIG.
Is counted.

When the forging start delay time elapses, both the automatic pressure increasing / decreasing step 132 in FIG. 1 and the forging pressure at the pressure reducing point P4 and the pressure increasing point P4 ′ are input to the displacement amount forging step 106 in the operation section 19 in FIG. By doing so, when the thickness of the workpiece to be welded is small, that is, when the displacement is large, the thickness is automatically changed with respect to the preset displacement of the thickness of the workpieces 12a and 12b. The electrode 3 is raised by the driving means 13 to reduce the electrode pressurization to the decompression point P4. When the thickness of the workpieces 12a and 12b being welded is large, that is, when the displacement is small, the electrode is automatically driven. The electrode 3 is lowered by the means 13 to increase the electrode pressure to the pressure increasing point P4 '.

In the first embodiment, whether to reduce or increase the forging pressure is determined by the magnitude of the forging pressure input value with respect to the electrode pressing force value, but the actual form 3 is determined by the displacement amount during welding. This is automatically determined, and the operation of reducing or increasing the pressure is performed.

(Embodiment 4) FIG. 4 shows the proportionality of the electrode pressing force to the amount of electrode movement when the elastic body as the urging means 4 expands and contracts. L on the horizontal axis represents the electrode movement (mm), and W on the vertical axis represents the electrode pressing force (g). Graph 140 of FIG.
3 is a graph when the initial weight when the electrode 3 comes into contact with the workpieces 12a and 12b in FIG. 2, that is, when the pressing force is 0 g. The graph 141 in FIG. 4 shows that the type of the elastic body as the urging means 4 is changed when the electrode 3 in FIG. 2 is in the initial weight when the electrode 3 comes into contact with the workpieces 12a and 12b, that is, when the pressing force is 0 g. At the same time, elastic part number constant input step 1 in FIG.
The number and constant of the elastic body at 16 (elastic body 4 per 1 mm
FIG. 6 is a graph when a pressure is input.

The graph 142 in FIG. 4 shows the case where the initial weight is 50 grams (W3), and the graph 143 in FIG. 4 changes the type of the elastic body as the urging means 4 when the initial weight is 50 grams. Elastic body part number constant input step 11 in FIG.
6 is a graph when an article number and a constant (pressing force of the elastic body 4 per 1 mm) of the elastic body are input at 6.

For example, in the graph 142 of FIG.
When the electrode pressing force is input as 300 grams in the electrode pressing input step 111 of FIG.
At 14, a correction value equal to the initial weight is input as 50 grams. When the amount of contraction of the elastic body is determined in the electrode pressure correction value subtraction step 115 in FIG. 1, the input value of the electrode pressure is 300 grams−the initial weight is 50 grams = 250 grams. Assuming that the constant of the elastic body is 0.1 kg / mm, the calculation of the moving amount of the motor which is the driving means 13 in FIG. 2 is based on the amount of contraction of the elastic body ÷ the constant of the elastic body = moving distance, 0.25 kg ÷ 0.1 kg
/Mm=2.5 mm, and the upper slider 1
mm.

(Embodiment 5) When "ON" is selected in the "ON-OFF" selection step of the workpiece detection / displacement measuring means 27 in FIG. 2, the sensor 16 of the workpiece detection / displacement measuring means 27 is selected. Becomes effective, and when the off is selected, the sensor 1
6 is invalidated, and arbitrary workpiece detection position data is inputted by the preset position input means (not shown) in the workpiece contact and same position step 122 of FIG. 1, and the input position is set to the workpiece. The position is regarded as the same position as the contacted position and stored, and the digital coordinate value is displayed in the welding object contact position display step 126 in FIG.

(Embodiment 6) If "OFF" is selected in the "ON-OFF" selection step of the workpiece detection / displacement amount measuring means 27 in FIG. A step of inputting a position for switching the electrode descent from a high speed to a low speed at a position before the position based on the position where the welding object detection position data is input, that is, the position input in the near low speed position input step 127 in FIG. Electrode 3 by value
Descends from high speed to low speed.

For example, when the preset position is input as 16 mm, and the value input in the near low-speed position input step 127 in FIG. 1 is 1 mm, when the electrode 3 switches from high speed to low speed, 16 mm-1 mm = 15 mm. FIG.
The electrode 3 descends from the origin P0 at a high speed, and switches to a low speed when it descends by 15 mm.

(Embodiment 7) The electrode 3 is
The electrode pressure value is digitally displayed in an electrode pressure display step 128 of FIG. 1 in a section from the time when the electrodes 3a and 12b come into contact with each other until the pressure of the electrode 3 is reduced or increased while the welding is completed. The electrode pressing upper / lower limit determination process of FIG. 1 is performed when the electrode 3 contacts the workpieces 12a and 12b, when the electrode 3 is pressurized, and when the pressure of the electrode 3 is reduced or increased. At 129, an upper limit value and a lower limit value of the electrode pressure value are set, and if the electrode pressure value is out of the range, an abnormal signal is output, and an abnormal alarm is performed after the operation of the resistance welding apparatus in FIG. (Not shown), an alarm is issued to stop the apparatus.

(Eighth Embodiment) Workpieces 12a and 12b
1 is counted by an electrode polishing preset counter (not shown) every time the electrode is produced.
After the electrode polishing preset counter reaches the preset set value, the electrode 3 is automatically polished periodically by an electrode polishing apparatus (not shown) and the electrode automatic polishing step 131 of FIG.

[0075]

As described above, according to the present invention, the electrode pressing force from the time when the electrode comes into contact with the workpiece to the end of energization to the time when the electrode is maintained at the forging pressure is reduced by the weight of the electrode pressing force supply mechanism itself. Since the pressing force of only the expansion and contraction of the elastic body of the urging means can be numerically managed without being added, a minimal electrode pressing force is obtained,
It is possible to perform thermocompression bonding or spot welding on a very small conductor wire or conductor part.

Further, by detecting the displacement sensor or the temperature sensor at the time of welding, the electrode to be welded is pressurized by forging pressure, so that the quality of the thermocompression bonding or spot welding result of the workpiece can be stabilized. Since the thickness of the workpiece is measured and the temperature of the electrode is controlled, a workpiece of high quality thermocompression or spot welding can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view of a resistance welding method according to first to eighth embodiments of the present invention.

FIG. 2 is a perspective view of a resistance welding apparatus using the resistance welding method of the present invention in the first to eighth embodiments of the present invention.

FIG. 3 is a welding operation diagram according to the first to eighth embodiments of the present invention.

FIG. 4 is a diagram showing a proportional relationship between an electrode moving amount and an electrode pressing force according to a fourth embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 upper slider 2 lower slider 3 electrode 4 urging means 5 locking part 6 urging force control means 7 pull-out prevention part 8 contact end 9 urging end 10 fulcrum 11 weight 12a welded object 12b welded object 13 drive means 14 screw Reference Signs List 15 screw portion 16 displacement sensor 17 displacement amount measurement unit 18 control unit 19 operation unit 20 temperature sensor 21 temperature measurement unit 22 cooling unit 23 welding power supply 24 lever unit 27 welding object detection unit, displacement amount measurement unit 28 welding current measurement unit L1 Electrode falling section L2 Electrode pressurizing and upsetting section L3 Forging section L4 Electrode rising section P0 Origin P1 Low speed point P2 Contact point of workpiece P3 Start point of pressure reduction or pressure increase of electrode pressure P4 Pressure reduction point P4 'Pressure increase Point 101 Electrode moving process 102 Workpiece contact detection process 103 Electrode pressing process 104 Electrode energizing process 105 Displacement measurement Step 106 Displacement forging step 107 Displacement welding end delay step 108 Electrode holding step 109 Electrode temperature forging step 110 Electrode temperature welding end delay step 111 Electrode force input step 112 Driving means movement calculation step 113 Electrode force output step 114 Electrode force Pressure correction value input step 115 Electrode pressure correction value subtraction step 116 Elastic body part number constant input step 117 Drive means electrode forging step 118 Electrode elevating speed input step 119 Workpiece contact position storage step 120 Workpiece contact position display step 121 Workpiece contact detection and displacement amount measurement process 122 Workpiece contact contact and same position process 123 Electrode speed switching process 124 Electrode positioning operation process 125 Electrode jog operation process 126 Workpiece workpiece contact and same position display process 127 Position input process 128 Electrode pressing force display process 129 Electrode pressing force up / down Judgment process 130 Electrode polishing frequency counting process 131 Electrode automatic polishing operation process 132 Automatic pressure increasing / decreasing process 140 Graph of initial weight when electrode 3 abuts on workpieces 12a and 12b 141 Part number and constant of elastic body for graph 140 143 Graph when the initial weight is 50 grams 143 Graph when the part number and constant of the elastic body are changed with respect to the graph 142

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B23K 11/30 350 B23K 11/30 350 // B23K 101: 38 101: 38 (72) Inventor Yoshiyuki Shimatani Osaka 1006 Kadoma, Kamon, Fumonma-shi Matsushita Electric Industrial Co., Ltd. F term (reference) 4E065 EA00 EA06

Claims (18)

[Claims] A step of causing the electrode to approach and separate from the workpiece; a step of detecting that the electrode is in contact with the workpiece; a step of pressing the workpiece with the electrode; Energizing step, measuring the displacement of the thickness of the workpiece during welding, and reducing or increasing the pressure of the electrode when the displacement of the workpiece during welding reaches a predetermined value A step of measuring a welding end delay time for stopping the energization after a certain time when the displacement amount of the work being welded reaches a predetermined value during welding, and a certain time for the work to be welded by the electrode after the welding is completed, Maintaining the pressurization by the above-described reduced pressure or increased pressure. 2. A step of causing an electrode to approach and leave an object to be welded, a step of detecting that the electrode abuts on the object to be welded, a step of pressing the electrode by an electrode, and a step of applying a welding current to the electrode. Energizing step, measuring the amount of displacement of the thickness of the workpiece during welding, and reducing or increasing the pressure of the electrode when the temperature of the electrode during welding reaches a predetermined value, A step of measuring a welding end delay time for stopping the energization after a certain time when the temperature of the electrode during welding reaches a predetermined value,
Maintaining the pressurization at a reduced or increased pressure for a certain period of time with an electrode after welding is completed by an electrode. 3. A step of inputting an urging force to an object to be welded to an operation section as an electrode pressing force, a step of calculating the electrode pressing force to a moving amount of the driving means by a control section, and an urging means connected to the driving means. 3. The resistance welding method according to claim 1, further comprising a step of obtaining an electrode pressing force by expansion and contraction of the elastic body. 4. In the step of pressurizing an object to be welded by an electrode, when the electrode comes into contact with the object to be welded, the contact weight of the electrode with respect to the object to be welded is smaller than the weight of the electrode force supply mechanism. The resistance welding method according to any one of claims 1 to 3, which can be obtained. 5. In the step of applying pressure to an object to be welded by an electrode, the electrode has the same value as the contact weight of the electrode pressing force supply mechanism with respect to the object to be welded when the electrode comes into contact with the object to be welded, or at least more than that value A step of inputting a small value to the operation unit as an electrode pressing force correction value, and an electrode pressing force obtained by subtracting the electrode pressing force correction value from the value obtained by inputting the urging force to the workpiece to the operation unit as the electrode pressing force. Calculating the amount of movement of the driving means. 6. A part number of the elastic body, a pressure constant for the expansion and contraction of the elastic body, and a correction value of the electrode pressing force are input to the operation unit in accordance with replacement of the elastic body as the urging means for obtaining the electrode pressing force. The resistance welding method according to any one of claims 1 to 5, wherein an electrode pressing force corresponding to the type of the workpiece is obtained by the step of performing. 7. A step in which an electrode presses an object to be welded, and a step of driving a driving means in a minus direction to reduce the pressure of the electrode during welding, or a step of driving the driving means in a plus direction to reduce the pressure of the electrode. 7. The method according to claim 1, further comprising a step of increasing the pressure and a step of inputting an electrode lifting / lowering speed together with the electrode pressing force to the operation unit.
The resistance welding method according to any one of the above. 8. The method according to claim 1, further comprising a step of storing, in the control unit, a position at which the tip of the electrode abuts on the workpiece, and a step of displaying the position in digital coordinate values. Resistance welding method. 9. A method of detecting an object to be welded and measuring an amount of displacement, comprising:
If "On" is selected in the "off" selection step, the sensor of the workpiece detection and displacement amount measuring means is enabled, and if "off" is selected, the sensor is disabled and the preset position input means detects any workpiece detection position. The resistance welding method according to any one of claims 1 to 8, comprising a step of inputting data and a step of storing the input position as the same position as the position in contact with the workpiece. 10. When "ON" is selected in the "ON-OFF" selection step of the workpiece detection and displacement amount measuring means, the preset position input means inputs position data for switching the speed of electrode lowering from high speed to low speed. A step of performing a positioning operation of the driving means until the electrode is switched to a low speed after starting the high-speed descent of the electrode, and a step of performing a jog operation of the driving means from the low-speed descent to detecting an object to be welded at an arbitrary position, The resistance welding method according to any one of claims 1 to 9, comprising a step of positioning the drive means until the electrode is raised to the origin after welding is detected after detecting the workpiece. 11. When “OFF” is selected in the “ON-OFF” selection step of the workpiece detection and displacement amount measuring means, the stored position is regarded as the same position as the position in contact with the workpiece, and the stored position is always digitally displayed. The resistance welding method according to any one of claims 1 to 10, comprising a step of displaying the coordinates by a coordinate value. 12. When "OFF" is selected in the "ON-OFF" selection step of the workpiece detection and displacement amount measuring means, a position at which arbitrary workpiece detection position data is input by the preset position input means is used as a reference. Inputting a position at which the electrode descent is switched from high speed to low speed at a position in front of the position. 13. When the thickness of the workpiece to be welded is small, ie, the displacement is large, with respect to the preset displacement of the thickness of the workpiece, the electrode pressure is automatically increased. 13. The method according to claim 1, further comprising an automatic pressure increasing / decreasing step of automatically increasing the electrode pressure when the thickness of the workpiece to be welded during welding is large, that is, when the displacement is small. Resistance welding method. 14. The resistance welding method according to claim 1, further comprising, at the beginning of the step of applying a welding current to the electrode, a welding start delay section for delaying the application of electricity. 15. The resistance welding method according to claim 1, further comprising a pressure reduction or pressure increase start delay section in which the pressure of the electrode is delayed to a pressure reduction or pressure increase during welding. 16. The resistance welding according to claim 1, further comprising a holding section for holding the work to be welded at a reduced or increased pressure value for a predetermined time after the welding is completed. Method. 17. A step of displaying an electrode pressure value as a digital value in a section from the time when the electrode comes into contact with the workpiece to the time when welding is completed and the pressure of the electrode is reduced or increased. The upper and lower electrode pressure values are set when the electrode contacts the workpiece, when the electrode is pressurized, and when the pressure of the electrode is reduced or increased. 2. A step of outputting an abnormal signal if the pressure value is out of the range, and performing an abnormal alarm after the operation of the resistance welding apparatus is completed.
17. The resistance welding method according to any one of claims to 16. 18. A step of counting the number of times of electrode polishing with an electrode polishing preset counter each time a workpiece is produced, and automatically polishing an electrode by an electrode polishing apparatus after the electrode polishing preset counter reaches a preset set value. 18. The resistance welding method according to claim 1, comprising the steps of: