JP2022143683A - Intermittent seam weld measuring apparatus and intermittent seam weld measuring method - Google Patents

Abstract

To provide an intermittent seam weld measuring apparatus which can measure welding current and so on of intermittent seam weld without omission, and provide determination result for the entire intermittent seam weld.SOLUTION: A measurement time and a measurement rest time, that are same values as a welding time and welding rest time in an intermittent seam weld measuring apparatus when performing intermittent seam weld that repeats the welding time during which welding current is applied to an object 5 to be welded and the welding rest time during which welding current is not applied to the object and welds the object to be welded, is set to a measurement setting part 21, a current trigger circuit 23 detects the rise of a welding current value, and obtains a welding measurement start trigger. A measurement circuit 25 measures a current value from the time of the welding measurement start trigger obtained in the current trigger circuit until the measurement time set in the measurement setting part elapses. A main calculating part 22 performs calculation processing of the measured measurement value after the measurement time has elapsed until the measurement rest time elapses. A determination output part 27 determines a welded state of the object to be welded on the basis of the calculated value obtained in the calculating part.SELECTED DRAWING: Figure 1

Description

The present invention relates to an intermittent seam welding measuring apparatus and an intermittent seam welding measuring method.

Intermittent seam welding is a welding method that repeats a cycle of welding in which current is applied to a rotating electrode and pause in which current is not applied. The welding time is 1-5 cycles (eg 3 cycles) or about 5-200 ms, and the rest time is 1-3 cycles (eg 1 cycle) or about 5-60 ms. The repetition time may extend over several minutes.

Conventional measuring instruments measure the current value of the welding circuit (hereinafter referred to as the welding current value) and the voltage value between the rotating electrodes within the welding range (hereinafter referred to as the welding current value and the voltage value between the rotating electrodes). current value, etc.). In this case, since the welding current value, etc. is measured without specifying each section of the energization time zone and the rest time zone, after measuring the welding current value, etc. in the welding range, the first 0.5 cycle of the section where no energization is performed Alternatively, the welding current value or the like is measured at 1 ms, and the time for judging that the energization is finished is measured to determine the end of the measurement.

Further, the effective value of the welding current value, the arithmetic mean effective value and the peak value are calculated from the measured values of the welding current value. The arithmetic mean effective value is obtained by calculating the effective value of the welding current value in units of 0.5 cycles or 1 ms and averaging the results in the welding range. It is checked whether or not the effective value, arithmetic mean effective value, and peak value of the obtained welding current values are within the judgment range, and the judgment is output.

Japanese Patent No. 5305172

In some cases, the total time of the time to determine that energization has ended, the time to calculate the effective value of the welding current value, etc., and the determination output time may be longer than the pause time. In this case, the welding current value and the like for the next welding cannot be measured.

In addition, since a determination is output for each measurement, it is not possible to obtain a determination result for the entire intermittent seam welding.

One aspect of the present invention provides a seam welding measurement device that includes a measurement setting section, a current trigger circuit, a measurement circuit, an arithmetic processing section, and a determination output section. The measurement setting unit is set to the intermittent seam welding device in the intermittent seam welding measurement device when welding the object to be welded by repeating the welding time during which the welding current is applied to the object to be welded and the welding pause time during which the welding current is not applied. Set the measurement time and measurement pause time to be the same values as the welding time and welding pause time, respectively. A current trigger circuit detects the current value of the welding current to obtain a welding measurement start trigger. The measurement circuit measures the current value of the welding current from the time of the welding measurement start trigger obtained by the current trigger circuit until the measurement time set by the measurement setting section elapses. The arithmetic processing unit performs arithmetic processing on the measured values measured by the measurement circuit from after the measurement time elapses until the measurement pause time elapses. The judgment output section judges the welding state of the object to be welded based on the calculated value obtained by the arithmetic processing section.

The measurement setting unit is set to the intermittent seam welding device in the intermittent seam measurement welding device when welding the object to be welded by repeating the welding time during which the welding current is applied to the object to be welded and the welding pause time during which the welding current is not applied. Set the measurement time and measurement pause time to be the same values as the welding time and welding pause time, respectively. The measurement circuit measures the current value of the welding current from the time of the welding measurement start trigger to the elapse of the measurement time set by the measurement setting section. The arithmetic processing unit performs arithmetic processing of the measured value from after the measurement time elapses until the measurement pause time elapses. That is, since the measurement values are calculated within the preset measurement pause time, all welds can be measured and calculated. Therefore, it is possible to determine the measured values such as individual welding current values, and furthermore, determine the measured values such as the overall welding current value.

According to one aspect of the present invention, the welding current value and the like of all welding of intermittent seam welding are measured, the quality of welding is determined without omission based on individual welding current values, and the quality of welding is determined based on the overall welding current value. Defect judgment can be performed.

FIG. 1 is a configuration diagram of an intermittent seam welding measuring device and a welding power source according to an embodiment of the present invention. FIG. 2 is a timing chart for repeating energization and resting of intermittent seam welding by the welding power source according to the embodiment of the present invention. FIG. 3 is a timing chart showing setting of measurement time and pause time by the measurement setting section of the intermittent seam welding measurement apparatus according to the embodiment of the present invention. FIG. 4 is a timing chart for repeating measurement of the welding state of the object to be welded and arithmetic processing by the measurement circuit of the intermittent seam welding measurement apparatus according to the embodiment of the present invention. FIG. 5 is a timing chart showing the determination output when the determination is poor and when the determination is good after repeating the measurement and arithmetic processing shown in FIG. FIG. 6 is a flow chart showing processing of the welding power source according to the embodiment of the present invention. FIG. 7 is a flow chart showing processing of the intermittent seam welding measuring device according to the embodiment of the present invention.

Hereinafter, an intermittent seam welding measuring apparatus and an intermittent seam welding measuring method according to embodiments of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals, and the description thereof is omitted.
(Basic configuration of intermittent seam welding measuring device)

FIG. 1 is a configuration diagram of an intermittent seam welding measuring device and a welding power source according to an embodiment of the present invention. This embodiment will be described with reference to FIG.

A welding power source 1 is a power source for performing intermittent seam welding, and as shown in FIG. Prepare. One end of the primary winding P of the transformer T is connected to one end of a single-phase AC power supply (hereinafter abbreviated as an AC power supply) (not shown), and the other end of the primary winding P is connected to an AC power supply via thyristors 14a and 14b. Connected to the other end of the power supply. The welding power source 1, the transformer T, and the rotating electrodes 4a and 4b constitute an intermittent seam welding device for intermittently seam welding the object 5 to be welded.

Both ends of the secondary winding S of the transformer T are connected to rotating electrodes 4a and 4b. Welding current is supplied to the rotating electrodes 4a and 4b from an AC power source through the transformer T and the thyristors 14a and 14b.

In the intermittent seam welding, a welding current is applied while the rotating electrodes 4a and 4b are rotating while the object 5 to be welded is pressed between the disk-shaped rotating electrodes 4a and 4b. to heat. Furthermore, by moving the rotating electrodes 4a and 4b, the welding objects 5 are continuously joined while shifting the welding points.

The welding current setting unit 11 sets the magnitude of the welding current for intermittent seam welding, the welding time (energization time) of the welding current, and the welding pause time. The welding current control unit 12 controls the magnitude of the welding current set by the welding current setting unit 11, the welding time (energization time) of the welding current, and the welding pause time, and outputs a control signal to the ignition pulse generation circuit 13. .

The ignition pulse generating circuit 13 generates an ignition pulse based on the control signal from the welding current control section 12, and outputs the ignition pulse to the gates of the thyristors 14a and 14b. The thyristors 14a and 14b are turned on according to the ignition pulse from the ignition pulse generating circuit 13, thereby allowing the welding current to flow. The display unit 15 displays the magnitude of the welding current, the welding time (energization time) of the welding current, and the welding pause time.

The transformer T has a primary winding P and a secondary winding S that are electromagnetically coupled, transforms an AC voltage of an AC power supply, and outputs the result to the secondary winding S side. The current sensor 3 has a coil wound around a toroidal core and a secondary winding S of a transformer T passing through the toroidal core. is output to the current trigger circuit 23 .

The measuring instrument 2 includes a measurement setting section 21, a main processing section 22, a current trigger circuit 23, a current sensor 3, a waveform restoration circuit 24, a secondary current measurement circuit 25, a secondary voltage measurement circuit 26, a judgment output section 27, a display A portion 28 is provided.

The measurement setting unit 21 includes an input unit such as a touch panel and an operation panel, and repeats a welding time during which current is applied to the object to be welded 5 and a welding pause time during which the current is not applied. In the intermittent seam welding measuring device, a measurement time and a measurement pause time are set that are the same values as the welding time and the welding pause time set in the intermittent seam welding device. Since the welding time of the welding power source is 3 cycles as shown in FIG. 2, the measurement time is also set to 3 cycles as shown in FIG. Since the welding rest time of the welding power source is one cycle as shown in FIG. 2, the measurement rest time is also set to one cycle as shown in FIG. The measurement time is the time for measuring the current value of the welding current flowing on the secondary winding S side of the transformer T. As shown in FIG.

The main processing unit 22 is composed of a CPU (Central Processing Unit), stores the measurement time and the measurement rest time set by the measurement setting unit 21 in a memory (not shown), and measures the measurement time and the measurement rest time for the secondary current measurement. Output to circuit 25 .

The current trigger circuit 23 uses an analog current differential waveform obtained from the output of the time differential value of the measured current consisting of the induced voltage detected by the current sensor 3 to obtain a welding measurement start trigger, which is the start of current flow.

The waveform restoration circuit 24 includes an operational amplifier circuit and an integration circuit, amplifies the analog differential current waveform detected by the current sensor 3 by the operational amplifier circuit, integrates the amplified current differential waveform by the integration circuit, Restore the current waveform.

The secondary current measurement circuit 25 corresponds to the measurement circuit of the present invention and includes an A/D converter (analog/digital converter). , and the measurement time set by the measurement setting unit 21 are input.

The secondary current measurement circuit 25 converts the current waveform restored by the waveform restoration circuit 24 into a digital signal by an A/D converter from the time of the welding measurement start trigger until the measurement time elapses. A current value flowing through the winding S is measured. That is, the process of measuring the welding state of the object 5 to be welded is repeatedly performed.

The secondary voltage measuring circuit 26 measures the voltage value between the rotating electrodes 4 a and 4 b and outputs the measured voltage value to the main processing section 22 .

The main processing unit 22 calculates the current effective value, current arithmetic mean effective value, Perform processing to calculate the current peak value. The main processing unit 22 measures the voltage effective value, the voltage arithmetic mean effective value, the voltage Perform processing to calculate the peak value.

The determination output unit 27 determines the object to be welded 5 based on the current effective value, the current arithmetic mean effective value, the current peak value, the voltage effective value, the voltage arithmetic mean effective value, and the voltage peak value obtained by the main processing unit 22. Determine the welding state of The display unit 28 displays the computation result of the main computation processing unit 22 and the determination result of the determination output unit 27 .

Next, the operation of the seam welding measuring instrument and welding power source configured in this manner will be described with reference to the drawings.

First, the operation of the welding power source 1 will be described with reference to the timing chart of repeating energization and suspension of intermittent seam welding by the welding power source 1 shown in FIG. 2 and the flowchart showing the processing of the welding power source 1 shown in FIG.

First, the welding current setting unit 11 sets the magnitude of the welding current for intermittent seam welding, the welding time (energization time) of the welding current, and the welding pause time (step S11).

The welding current control unit 12 controls the magnitude of the welding current set by the welding current setting unit 11, the welding time (energization time) of the welding current, and the welding pause time. The firing pulse generating circuit 13 outputs the generated firing pulses to the thyristors 14a and 14b.

The thyristors 14a and 14b pass a welding current from the AC power supply to the primary winding P of the transformer T according to the ignition pulse. Further, a welding current flows through the secondary winding S of the transformer T, and this welding current flows through the disk-shaped rotating electrodes 4a and 4b. Thereby, intermittent seam welding is started (step S13).

In this case, as shown in FIG. 2, the welding current has a welding time (energization time) from time t0 to t6, a welding rest time from time t6 to t8, a welding time from time t8 to t14, and a welding rest time from time t14 to t16. Time . . . becomes a repeated increase/decrease transition state of the current value.

Next, the welding current control unit 12 and the ignition pulse generating circuit 13 stop the intermittent seam welding to stop the welding (step S15).

Next, the measuring instrument 2 determines whether or not the intermittent seam welding is finished (step S17). In step S17, if the intermittent seam welding is not finished, the measuring instrument 2 returns to step S11 and performs the processing from step S11 to step S15. When the intermittent seam welding is finished, the measuring device 2 finishes the process.

Next, the operation of the measuring device 2 will be described with reference to the timing charts shown in FIGS. 3, 4 and 5 and the flow chart of the measuring device 2 shown in FIG.

First, the measurement setting unit 21 determines the welding time and the welding pause time in the intermittent seam welding for welding the weld object 5 by repeating the welding time during which the current is applied to the welding object 5 and the welding pause time during which the current is not applied. (step S21).

In this case, as shown in FIG. 3, the measurement setting unit 21 sets the measurement time from time t0 to t6, the measurement rest time from time t6 to t8, the measurement time from time t8 to t14, the measurement rest time from time t14 to t16, and so on. set repeatedly. That is, the measuring device 2 is set with a measurement time and a measurement rest time synchronized with and equal to the welding time and welding rest time set by the welding power source 1 .

Next, the main processing unit 22 stores the measurement time and the measurement pause time set by the measurement setting unit 21 in the storage device, and sets the measurement timing based on the measurement time and the measurement pause time (step S23). The main processing unit 22 outputs measurement timing information to the secondary current measurement circuit 25 .

The current trigger circuit 23 determines whether or not the start of the welding current has been detected from the current differential waveform detected by the current sensor 3 (step S25). When the current trigger circuit 23 detects the start of welding current flow (rise of the welding current value), the current trigger circuit 23 obtains a welding measurement start trigger as the start of welding current flow.

Next, the waveform restoration circuit 24, the secondary current measurement circuit 25, the secondary voltage measurement circuit 26, and the main processing unit 22 start measuring the welding current value and the welding voltage value (step S27).

Specifically, the waveform restoration circuit 24 amplifies the analog differential current waveform detected by the current sensor 3 with an operational amplifier circuit, integrates the amplified current differential waveform with an integration circuit, and restores the current waveform. .

The secondary current measurement circuit 25 receives the welding measurement start trigger obtained by the current trigger circuit 23 and the measurement time set by the measurement setting section 21 . As shown in FIG. 4, the secondary current measurement circuit 25 measures the current restored by the waveform restoration circuit 24 from the welding measurement start trigger time (for example, time t0) until the measurement time (for example, time t6) elapses. The waveform is converted into a digital signal by an A/D converter, and the secondary current value (welding current value) is measured. Also, the secondary current measuring circuit 25 measures the welding time (step S29).

As shown in FIG. 4, the secondary current measurement circuit 25 measures the current value during the measurement time from time t0 to t6, and measures the current value during the measurement time from time t8 to t14. measure the value.

After the welding time (measurement time) has elapsed, the measuring instrument 2 stops the waveform restoration circuit 24, the secondary current measurement circuit 25, and the secondary voltage measurement circuit 26 (step S31). That is, the measurement pause time is from t6 to t8 and from t14 to t16.

The main processing unit 22 calculates the effective value and the like based on the current measurement value measured by the secondary current measurement circuit 25 from the time the measurement time elapses until the measurement pause time elapses (for example, time t78 in FIG. 4). Calculate (step S33).

As shown in FIG. 4, the main processing unit 22 calculates the current effective value, etc. within the measurement time t0 to t6 from the time the measurement time t6 to t8 has passed until the measurement pause time has passed. , the effective value of the current during times t8 to t14 is calculated from the time the measurement time from time t14 to time t16 has passed until the measurement pause time has passed.

Here, the main processing unit 22 calculates the effective value of the welding current value, the arithmetic average effective value, and the peak value from the measured value of the welding current value for each measurement time.

The determination output unit 27 performs individual determination as to whether the object to be welded 5 is non-defective or defective based on the calculation result obtained by the main processing unit 22 (step S35). Determination of whether the object to be welded 5 is good or bad is performed, for example, as follows. As shown in FIG. 5, when the peak value of the current value is within a predetermined value range, the product is determined to be "non-defective" (time t0 to t6). When the peak value of the current reaches the first threshold value, which is larger than the predetermined value range, the product is judged to be "defective" (time t8 to t14).

In addition, the determination of whether the welded object 5 is good or bad can be classified into, for example, "good", "defective NG1", and "defective NG2" based on the first and second thresholds. can be done. Furthermore, the judgment of the non-defective product of the welding target 5 is performed in multiple stages, for example, "good product", "defective product NG1", "defective product NG2", "defective product NG3", the first threshold value, the second threshold value , can be classified based on a third threshold.

After that, the determination output unit 27 stores the individual determination result, that is, the determination result for each measurement time in the storage device (step S37).

Next, the determination output unit 27 determines whether or not the intermittent seam welding has ended (step S39). If the intermittent seam welding is not finished in step S39, the determination output unit 27 returns to step S25 and performs the processing from step S25 to step S37.

When the intermittent seam welding is finished, the determination output unit 27 makes an overall determination that summarizes the individual determinations (step S41). After that, the determination output unit 27 stores the overall determination result in the storage device (step S43).

Next, several examples of judgment outputs when judging the welding object 5 as defective will be described with reference to the timing chart of FIG.

In a first example, if the welding target 5 is defective, the determination output unit 27 outputs the defect determination after the intermittent seam welding is completed. This makes it possible to output the determination of the entire welding.

In a second example, the determination output unit 27 performs a defect determination output (Low: NG) and continues the defect determination output when the welding target 5 is defective. In other words, when it is determined that the object to be welded 5 is defective in welding, it is possible to immediately output the defective determination and stop the welding.

In a third example, the determination output unit 27 performs a failure determination output (Low: NG) when the welding object 5 is defective, and after that, when the welding state of the welding object 5 becomes good ( High: within the judgment range) Stops outputting the defect judgment. This makes it possible to determine the location determined to be defective in welding.

In a fourth example, the judgment output unit 27 outputs the judgment after welding is finished when the object 5 to be welded is judged to be good.

As described above, according to the intermittent seam welding measuring apparatus according to the embodiment, the measurement setting unit 21 repeats the welding time during which the current is applied to the welding object 5 and the welding pause time during which the current is not applied. In the intermittent seam welding measurement device for welding, set the measurement time and the measurement rest time that are the same values as the welding time and the welding rest time set for the intermittent seam welding device.

The secondary current measurement circuit 25 measures the current value from the time of the welding measurement start trigger until the measurement time elapses. The main processing unit 22 performs arithmetic processing of the measured values after the measurement time has elapsed and until the measurement pause time has elapsed.

That is, the main processing unit 22 calculates the measured values during the preset pause time, that is, the interval from the measurement time to the measurement pause time, so that all welds can be measured and calculated. . Therefore, it is possible to determine the quality of welding based on individual welding current values, and further determine the quality of welding based on the overall welding current value.

Further, the secondary current measurement circuit 25 converts the current waveform restored by the waveform restoration circuit 24 into a digital signal and measures the current value from the time of the welding measurement start trigger until the measurement time elapses. , the welding current value, which is the secondary current, can be accurately and repeatedly measured for the measurement time.

Also, when the measuring instrument 2 is connected to the welding power source 1 that supplies current to the welding device via a communication network, that is, when the intermittent seam welding device and the intermittent seam welding measuring instrument can communicate information via the communication network. Secondly, the measuring instrument 2 receives signals indicating the welding time and the welding pause time from the welding power source 1 via the communication network. The measurement setting unit 21 can set the measurement time and the measurement pause time that are the same values as the welding time and the welding pause time received from the welding power source 1 via the communication network.

The present invention is not limited to the intermittent seam welding measuring apparatus according to the embodiment described above, and various modifications are possible without departing from the gist of the present invention.

1 Welding power source 2 Measuring instrument 3 Current sensors 4a, 4b Rotating electrode 5 Welding object 11 Welding current setting unit 12 Welding current control unit 13 Ignition pulse generation circuits 14a, 14b Thyristors 15, 28 Display unit 21 Measurement setting unit 22 Main calculation Processing unit 23 Current trigger circuit 24 Waveform restoration circuit 25 Secondary current measurement circuit 26 Secondary voltage measurement circuit 27 Judgment output unit

Claims (7)

In the intermittent seam welding measurement device when welding the object to be welded by repeating a welding time in which the welding current is applied to the object to be welded and a welding pause time in which the welding current is not applied,
a measurement setting unit that sets a measurement time and a measurement pause time that are the same values as the welding time and the welding pause time that are set in the intermittent seam welding apparatus;
a current trigger circuit that detects the current value of the welding current and obtains a welding measurement start trigger;
a measurement circuit for measuring the current value of the welding current from the time of the welding measurement start trigger obtained by the current trigger circuit until the measurement time set by the measurement setting unit elapses;
an arithmetic processing unit that performs arithmetic processing on the measured value measured by the measurement circuit after the measurement time elapses and until the measurement pause time elapses;
a determination output unit that determines the welding state of the object to be welded based on the calculated value obtained by the arithmetic processing unit;
An intermittent seam weld measurement device comprising: A waveform restoration circuit for restoring a current waveform by integrating an analog current differential waveform of the current value of the welding current,
The measurement circuit measures the welding current by converting the current waveform restored by the waveform restoration circuit into a digital signal from the time of the welding measurement start trigger until the measurement time elapses. 2. The intermittent seam welding measurement device according to 1. 3. The intermittent seam welding measuring device according to claim 1, wherein said judgment output unit outputs a judgment failure after the intermittent seam welding is finished when the welding state of said object to be welded is unsatisfactory. 3. The intermittent seam welding measuring apparatus according to claim 1, wherein said determination output unit outputs a defective determination output when the welding state of said object to be welded is unsatisfactory, and continues said defective determination output. 3. The determination output unit outputs a defective determination when the welded state of the object to be welded is unsatisfactory, and then stops outputting the defective determination when the welded state of the object to be welded becomes favorable. An intermittent seam weld measurement device as described. When the intermittent seam welding measuring device is connected to the intermittent seam welding device through a communication network, it receives a signal indicating the welding time and the welding pause time from the intermittent seam welding device via the communication network. ,
The intermittent seam welding measuring device according to any one of claims 1 to 5. In an intermittent seam welding measurement method for welding the object to be welded by repeating a welding time during which a welding current is applied to the object to be welded and a welding pause time during which the welding current is not applied,
setting a measurement time and a measurement rest time that are the same values as the welding time and the welding rest time set for the intermittent seam welding device,
detecting a current value of the welding current to obtain a welding measurement start trigger;
measuring the current value of the welding current from the time of the obtained welding measurement start trigger until the set measurement time elapses;
performing arithmetic processing of the measured values after the measurement time elapses and until the measurement pause time elapses;
determining the welding state of the object to be welded based on the obtained calculated value;
Intermittent seam weld measurement method.

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