JPH08309534A - Device for controlling welding heat input - Google Patents

Abstract

PURPOSE: To provide a device for controlling welding heat input reduce in a production cost, by providing a control means calculating and outputting a quantity of heat input based on welding current and voltage. CONSTITUTION: Seams 1 are, e.g. a boundary of the outer wall of a gas tank and this part is electrically welded. Sensors 2 are fitted near each of the seams 1. In sensor boxes 4, a faint signal detected with respective correspondent sensors 2 is shaped to generate a pulse. The heat input quantity is calculated and outputted based on the time interval of respective pulses outputted from the sensor box 4 as a sensor signal processing means and the welding voltage and the welding current outputted from a welding box 6 with a control box 5. By this constitution, the welding heat input quantities of plural seams can simultaneously be grasped and the weld quantity can be kept at the best.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding heat input control device for controlling the amount of heat input to a seam to be electrically welded.

[0002]

2. Description of the Related Art When metal is electrically welded, the welding strength of the seam depends on the amount of heat applied during welding. Therefore, the amount of welding heat input is determined according to the material and the portion of the welding when designing the building, and the welder moves the welding portion (arc discharge position) at a constant speed so as to match the prescribed amount of welding heat input. Weld.

[0003]

Conventionally, when welding with a prescribed welding heat input as described above, a heat input manager measures a welding voltage, a welding current and a welding speed for each welder and each welding pass. The heat input amount of the seam was calculated from this measurement result. However, the number of welders that can be managed by one heat input manager is limited. For this reason, it takes a lot of time, resulting in an increase in production cost. Further, in order to shorten the working time, it is necessary to increase the number of heat input managers, which makes it difficult to reduce the cost. Furthermore,
When the amount of heat input exceeds the limit range during welding, it has to be corrected after the work on the welded portion is completed, and this also takes a lot of time. The present invention has been made under such a background, and an object of the present invention is to provide a welding heat input management device capable of keeping the welding quality at an optimum level and reducing the production cost.

[0004]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a welding heat input management device for managing the heat input amount to a seam to be electro-welded. Welding current detection means for detecting a welding current flowing to the seam, welding voltage detection means for detecting a welding voltage applied to the seam, and at least two sensors mounted near the seam along the seam. A sensor signal processing means for generating a pulse when the signal output from each sensor is maximum, a time interval of each pulse output by the sensor signal processing means, the welding current, and the welding voltage based on And a control means for calculating and outputting the entered heat quantity.

According to a second aspect of the present invention, in the welding heat input management device according to the first aspect, each of the sensors detects a heat input portion on the seam by heat generated by arc discharge. It is characterized by doing.

Further, in the invention according to claim 3, in the welding heat input management device according to claim 1, each of the sensors detects a heat input portion on the seam by light generated by arc discharge. It is characterized by doing.

Further, in the invention according to claim 4, in the welding heat input management device according to claim 1, each of the sensors detects a heat input portion on the seam by an impact generated by arc discharge. It is characterized by doing.

Further, in the invention described in claim 5,
In the welding heat input management device according to any one of claims 1 to 4, the control means includes A / D conversion means for converting each of the welding current and the welding voltage into digital data.
A RAM in which the digital data is recorded, and the digital data is recorded in the RAM every predetermined time,
And a CPU for calculating an average heat input amount from the recorded contents of M.

Further, in the invention described in claim 6,
In the welding heat input management device according to any one of claims 1 to 4, the welding current detection means, the welding voltage detection means, and the A / D conversion means are stored in one welding box, A plurality of the welding boxes and the same number of the signal processing means as the plurality of the welding boxes are connected to the control means, and the digital data and the pulse are input respectively.

Further, in the invention according to claim 7, in the welding heat input management device according to any one of claims 1 to 4, the control means is connected thereto, and an acoustic signal or light emission is generated. It is characterized in that it has a notification means for emitting a signal or the like, and emits an acoustic signal or a light emission signal or the like based on the result of comparison between the heat input amount and a preset reference value.

[0011]

The control means includes a welding voltage applied to the seam,
The welding current flowing into the seam and the time interval of each pulse generated based on the respective output signals from two or more sensors mounted along the seam in the vicinity of the seam are input to enter the welding into the seam. Calculate the amount of heat. Further, the welding voltage, welding current, and each pulse are input from a plurality of welding boxes and the same number of signal processing means.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A welding heat input control apparatus according to an embodiment of the present invention will be described below with reference to the drawings. A. Configuration FIG. 1 is a block diagram showing a schematic configuration of the present embodiment.
In FIG. 1, 1, 1, ... Are seams. The seams 1, 1, ... Are boundaries of the outer walls constituting the gas tank, for example, and are electrically welded to these parts.
In FIG. 1, reference numerals 2, 2, ... Are sensors attached near the seams 1, 1 ,. Also 4, 4
.. is a sensor box, which shapes a weak signal detected by the corresponding sensor 2 to generate a pulse.

FIG. 2 is a configuration diagram showing in detail the first configuration example of the sensor 2 and the sensor box 4. In FIG. 2, 11-1 and 11-2 are metal members, respectively, and the seam 1 part of these boundaries is welded. Sensor 2
Are composed of thermocouples 2-1 to 2-3, which are attached along the seam 1 on the metal member 11-1 at equal intervals of a distance L (10 cm in this embodiment). The sensor box 4 inputs the voltage output from each thermocouple 2-1 to 2-3 and outputs a pulse at the peak (maximum) of the voltage. That is, since it is well known that the thermocouples 2-1 to 2-3 generate an electromotive force having a voltage according to the ambient temperature, the output voltage becomes higher as the position is closer to the part being welded. From this, it can be seen that welding is being performed in the vicinity of each thermocouple 2-1 to 2-3.

Reference numeral 5 is a control box, which is a pulse output from the sensor box 4 and welding boxes 6, 6 ...
・ The welding voltage and welding current detection values output from are input, and the welding heat input is calculated from these. This welding heat input amount is a display 3 for displaying a numerical value, a recorder 8 for recording various data on a memory card, a magnetic tape, etc., a printer 9 for printing the various data, a heat input manager and welding by sound and light. It is input to the alarm device 10 for notifying the welder of welding failure.

FIG. 3 is a block diagram showing a detailed structure of the control box 5 and the welding box 6. Note that FIG. 3 shows a configuration in which only one welding box 6 is connected to the control box 5. In welding box 6 shown in FIG. 3, power supply unit 12 outputs welding current I. While the welding current I is being output to the holder 7, the current sensor 1
The current is detected by 3. The detection result of the current sensor 13 (welding current I) and the output voltage V of the power supply unit 12 are A
The data is converted into digital data D by the / D converter 14 and sent to the control box 5.

The digital data D input to the control box 5 and the pulse P output from each processing box 4 (see FIG. 2) are input to the CPU 16 via the input I / F 15. The CPU 16 calculates the heat input amount J based on the pulse P and the digital data D. The output of the control box 5 is input to the display 3, the recorder 8, the printer 9, and the alarm device 10 via the output I / F 17 (see FIG. 2). The ROM 18 included in the control box 5 is a CPU
16 stores the processing procedure, and the RAM 19 stores the order of welding parts to be worked, and temporarily stores the digital data D, the calculation result (heat input amount J), and the like.
Reference numeral 20 is a timer that measures time according to an instruction from the CPU 16.

B. Operation FIG. 4 is a timing chart showing the operation of each part of the present embodiment and the timing of signal waveforms. FIG. 1 or FIG.
When the holder 7 shown in FIG.
A welding current I flows from (see FIG. 3). This welding current I
Is detected by the current sensor 13, the A / D conversion unit 14 performs digital conversion, and the control box 5 receives the digital data D including the data of the welding current I.

When time t elapses after the welding current I is detected, the welding voltage V data is also output from the A / D converter 14 as shown in FIG. This time t is a time provided to protect each device from various noises generated immediately after the start of welding (immediately after the arc is generated). Welding current I
During a time t after the detection of “c”, an arc stabilization timer (not shown) cuts off the welding voltage V input to the A / D converter 14.

When the welding current I begins to flow and the holder 7 moving on the seam 1 passes through the thermocouple 2-1 part, the thermocouple 2-1.
Is heated to generate thermoelectromotive force. Sensor box 4
Detects the peak of this thermoelectromotive force and outputs a pulse P (point a in the figure). When the CPU 16 detects the pulse P, the timer 20 starts measuring time from 0 by the timer 20, and thereafter, the digital data D is written in the RAM 19 at regular time intervals.

The holder 7 moving on the seam 1 is a thermocouple 2.
After passing the -2 part, the thermocouple 2-2 is heated to generate thermoelectromotive force. The sensor box 4 detects the peak of this thermoelectromotive force and outputs the pulse P again (point b in the figure). At this time, the CPU 16 reads the time T (the time between a and b is T1) from the timer 20 and once resets the measurement time of the timer 20 to zero. Further, the average welding voltage Vav between a and b and the same average current Iav are obtained from the digital data D written in the RAM 19. Here, since the heat input amount J per unit length in the seam 1 can be obtained as J = Vav · Iav · T / L (1), the time T1 between a and b is set as the time T. When used, J = Vav · Iav · T1 / L (1) ′. The CPU 16 displays the heat input amount J thus calculated on the display 3 and, at the same time, outputs it to the recorder 8 and the printer 9. Further, when the heat input amount J exceeds a preset value, the alarm device 10 notifies the welder or the heat input manager.

The holder 7 moving on the seam 1 is a thermocouple 2.
After passing the -3 part, the thermocouple 2-3 is heated to generate a thermoelectromotive force. The sensor box 4 detects the peak of this thermoelectromotive force and outputs the pulse P again (point c in the figure). Here, the CPU 16 reads the time T (the time between b and c is T2) from the timer 20 and ends the time measurement by the timer 20. Further, the average welding voltage Vav between b and c and the average current Iav are obtained from the digital data D written in the RAM 19. After that, the heat input amount J is obtained from the equation (1) as J = Vav · Iav · T2 / L (1) ″, and the display 3 and the recorder 8
To the printer 9. Also, as before, the heat input J
If the value exceeds a preset value, an alarm device 10 notifies the welder or heat input manager.

After that, if welding is started at another welding site, the welding current I is detected as described above, and the CPU
In response to this, 16 obtains the heat input amount J and outputs it.

C. Another Configuration Example In the above-described embodiment, an example using the thermocouple as the sensor 2 is shown. However, the sensor 2 may be configured as described below. FIG. 5 is a configuration diagram showing in detail the second configuration example of the sensor 2 and the sensor box 4. In FIG. 5, 21 is a seam 1 on the metal member 11-1.
It is a slit plate placed along. The slit plate 21 has slits 21-1 to 21-3 at equal intervals. Optical sensors 22-1 to 22-3 are attached to the respective portions of the slits 21-1 to 21-3.

As is well known, in electric welding (arc welding),
Emit a strong flash on the part being welded. Each optical sensor 22-1 ~
22-3 receives the flash light passing through the slits 21-1 to 21-3 and outputs an electric signal, and the sensor box 4
Outputs a pulse P at the peak of the electric signals from these optical sensors 22-1 to 22-3. In this embodiment, the operation other than the sensor 2 is the same as that of the above-mentioned embodiment, and the description thereof is omitted.

As described above, the control box 5 calculates, displays and records the heat input amount of the seam 1, and when the heat input amount exceeds a predetermined value, informs the heat input manager or the welder. The control box 5 can perform some of the above operations at the same time. That is, a plurality of welding boxes 6
By providing the same number of holders 7 and the holders 7 connected thereto, and the same number of sensors 2 and sensor boxes 4 (see FIG. 1), the heat input amount can be collectively controlled even during simultaneous welding work at a plurality of locations. can do.

In electric welding, a strong flash and a strong shock are generated at the contact portion during welding. Therefore, the sensor 2
An element that detects impact (for example, an acceleration sensor or other piezoelectric element) may be used. Further, in the configuration in which the portion in the arc discharge is detected by its heat, the sensor 2
Although the example in which the thermocouples (2-1 to 2-3) are used is shown in the above, a temperature sensor using a thermistor or a semiconductor may be used. Furthermore, although each sensor 2 is shown to have three detection elements (for example, thermocouples 2-1 to 2-3), in the present invention, other than this (two or four or more).
It may be.

[0027]

As described above, according to the present invention,
The control means controls each pulse generated based on a welding voltage applied to the seam, a welding current flowing to the seam, and output signals from two or more sensors mounted along the seam in the vicinity of the seam. Input the time interval and calculate the welding heat input to the seam. In addition, the welding voltage, welding current and each pulse are input from multiple welding boxes and the same number of signal processing means, so the welding heat input of multiple seams can be grasped at the same time, and the welding quality is kept at the optimum level. The effect that the welding heat input management device capable of reducing the production cost can be realized is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a welding heat input management apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing in detail a first configuration example of a sensor 2 and a sensor box 4 in the same embodiment.

FIG. 3 is a block diagram showing a detailed configuration of a control box 5 and a welding box 6 in the same embodiment.

FIG. 4 is a timing chart showing the operation of each part of the embodiment and the timing of signal waveforms.

FIG. 5 is a configuration diagram showing in detail a second configuration example of the sensor 2 and the sensor box 4 in the same embodiment.

[Explanation of symbols]

 1 seam 2 sensor 2-1 to 2-3 thermocouple 4 sensor box 5 control box 6 welding box 10 alarm device 13 current sensor 14 A / D converter 16 CPU 19 RAM 20 timer 22-1 to 22-3 optical sensor

Claims (7)

[Claims] 1. A welding heat input management device for managing the amount of heat input to a seam to be electrically welded, wherein a welding current detecting means for detecting a welding current flowing to the seam and a welding voltage applied to the seam are detected. Welding voltage detection means, at least two sensors mounted along the seam in the vicinity of the seam, sensor signal processing means for generating a pulse when the signal output from each sensor is at the maximum, and the sensor signal A welding heat input management device comprising: a control unit that calculates and outputs the heat input amount based on the time interval of each pulse output by the processing unit, the welding current, and the welding voltage. 2. The welding heat input management device according to claim 1, wherein each of the sensors detects a heat input portion on the seam by heat generated by arc discharge. 3. The welding heat input management device according to claim 1, wherein each of the sensors detects a heat input portion on the seam by light generated by arc discharge. 4. The welding heat input management device according to claim 1, wherein each of the sensors detects a heat input portion on the seam by an impact generated by arc discharge. 5. The A / D conversion means for converting each of the welding current and the welding voltage into digital data, a RAM (random access memory) in which the digital data is recorded, and the digital data. It is recorded in the RAM every predetermined time, and the average heat input is calculated from the recorded contents of the RAM C
PU (Central Processing Unit) is provided, The welding heat input management apparatus in any one of Claim 1 thru | or 4 characterized by the above-mentioned. 6. The welding current detection means, the welding voltage detection means, and the A / D conversion means are stored in one welding box, and the control means includes a plurality of the welding boxes and the plurality of the welding boxes. 5. The welding heat input management device according to claim 1, wherein the welding boxes and the signal processing means of the same number are connected and the digital data and the pulse are respectively input. 7. The control means includes a notification means connected to the control means for emitting an acoustic signal or a light emission signal, and the acoustic signal or the light emission based on a comparison result between the heat input amount and a preset reference value. The welding heat input management device according to any one of claims 1 to 4, which emits a signal or the like.