JP2007160350A - Method for setting welding condition of arc welding robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an operator to determine a set value of an optimum welding condition parameter corresponding to a workpiece during a limited arc welding period. <P>SOLUTION: Arc welding is performed by an arc welding robot by transmitting a plurality of welding condition parameters from a robot controller to a welding power unit through a communication line and controlling the output of the power unit based on the set value of the received welding condition parameters. In the method of setting the welding conditions of the arc welding robot, one or more readjustment welding condition parameters (the readjustments) are selected preliminarily among a plurality of welding condition parameters, with one or more adjusters corresponding to the readjustments installed in the welding power unit, and with the set value of the readjustments changed by the adjusters. On the basis of the changed value of the readjustments, the welding power unit is controlled in the output to perform the arc welding in this method. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a welding condition setting method for an arc welding robot for changing a setting value of a welding condition parameter during welding.

  When performing arc welding using an arc welding robot, welding is performed by reading a set value of a plurality of welding condition parameters stored in advance for each workpiece. The welding condition parameters include a welding voltage set value and a welding current set value (wire feed speed). FIG. 6 is a current waveform diagram of CO2 / MAG welding, in which the short circuit period and the arc period are repeated. As shown in the figure, since the spatter generation amount and arc stability change depending on the short-circuit current ramp time T1 and the short-circuit current suppression value Is during the short-circuit period, both values are set to appropriate values according to the workpiece as welding condition parameters. There is a need to. In addition to these, there are many welding condition parameters such as the current value at the start of the arc and the anti-stick voltage at the end of the arc.

  Setting each of the many welding condition parameters described above to an appropriate value in the welding process is very laborious and reduces production efficiency. For this reason, as a welding condition setting method, it is common to assume a plurality of types of workpieces as a reference in advance, store in advance standard values of each welding condition parameter for each workpiece, and read and use these values during welding. It is. However, when performing welding in the welding process, it is often the case that the welding quality is improved by further fine-tuning some of the welding condition parameters from the standard values. At this time, test welding is performed in the welding process, and fine adjustment of the welding condition parameters is performed. Hereinafter, the fine adjustment method of the welding condition parameter in the arc welding robot system will be described.

FIG. 7 is a system configuration diagram of a conventional arc welding robot. The robot control device WRS transmits the standard value of the welding condition parameter stored in advance for each workpiece as a welding condition parameter signal Wp to the welding power supply device PS via the communication path. Furthermore, the robot controller WRS outputs a robot drive signal Wc for operating the robot body WR.
The welding power supply device PS performs output control based on the received standard value of the welding condition parameter signal Wp, and outputs a wire feeding drive signal Sw for controlling the wire feeding device WF. The welding wire 4 is fed through the welding torch TH by the wire feeding device WF, and an arc is generated between the workpiece 2 and welding is performed.

  When finely adjusting the standard value of the welding condition parameter, the teach pendant TP is used as follows. Of the many welding condition parameters, those to be finely adjusted are designated in advance as readjustment welding condition parameters. The teach pendant TP is provided with, for example, an increase button and a decrease button, and outputs an increase / decrease signal Ud whose value becomes 1 when the increase button is pressed and whose value becomes -1 when the decrease button is pressed. The robot control device WRS finely adjusts the standard value of the welding condition parameter specified as the readjustment welding condition parameter by increasing or decreasing the increase / decrease signal Ud. The fine adjustment value of the readjustment welding condition parameter is transmitted to the welding power source device PS every moment.

  FIG. 8 is a detailed view of the robot controller shown in FIG. In the welding condition storage circuit WM, standard values of welding condition parameters corresponding to the workpiece are stored. The central processing circuit CPU reads the standard value of the welding condition parameter from the welding condition storage circuit WM via the bus line BL and outputs it to the first communication interface CI1 via the bus line BL. The first communication interface CI1 communicates the standard value of the welding condition parameter as a welding condition parameter signal Wp to the welding power source device PS via the communication path. The robot drive circuit WC outputs a robot drive signal Wc based on a command from the central processing circuit CPU.

  The processing at the time of fine adjustment of the readjustment welding condition parameter designated in advance among the welding condition parameters is as follows. The second communication interface CI2 receives the increase / decrease signal Ud from the teach pendant TP. The central processing circuit CPU reads the standard value of the readjustment welding condition parameter from the welding condition storage circuit WM via the bus line BL, finely adjusts the standard value by increasing / decreasing the value according to the increase / decrease signal Ud, and the bus line BL. To the first communication interface CI1. The first communication interface CI1 communicates the fine adjustment value of the readjustment welding condition parameter to the welding power source device PS via the communication path.

  FIG. 9 is a detailed view of the welding power source apparatus shown in FIG. In the figure, the main power supply circuit INV supplies power between the welding wire 4 and the workpieces 1 and 2 with a commercial power supply such as three-phase 200 V as an input. The third communication interface CI3 receives the welding condition parameter signal Wp via the communication path. The main control circuit SC receives the welding condition parameter signal Wp from the third communication interface CI3, and controls the output of the main power supply circuit INV based on the standard value of the welding condition parameter. The feeder drive circuit SW outputs a wire feed drive signal Sw based on a command from the main control circuit SC. The fine adjustment of the readjustment welding condition parameter is also received as one of the welding condition parameter signals Wp.

If the fine adjustment method of the readjustment welding condition parameter is elaborated, the following 7 steps are performed.
(1) Readjustment In order to finely adjust the standard value of the welding condition parameter, the operator presses the increase button or phenomenon book or mm of the teach pendant TP while observing the welding state.
(2) The increase / decrease signal Ud is transmitted from the teach pendant TP to the second communication interface CI2.
(3) The central processing circuit CPU inputs the increase / decrease signal Ud from the second communication interface CI2, and reads the standard value of the readjustment welding condition parameter from the welding condition storage circuit WM.
(4) The central processing circuit CPU calculates the fine adjustment value by increasing / decreasing the standard value of the readjustment welding condition parameter by the value of the increase / decrease signal Ud.
(5) The central processing circuit CPU outputs the fine adjustment value of the readjustment welding condition parameter to the first communication interface CI1.
(6) The first communication interface CI1 transmits the fine adjustment value of the readjustment welding condition parameter to the third communication interface CI3 as one of the welding condition parameter signals Wp.
(7) The main control circuit SC inputs the fine adjustment value of the readjustment welding condition parameter from the third communication interface CI3, and controls the output of the welding power source device PS based on the fine adjustment value.

Japanese Patent Laid-Open No. 7-116844

  When performing arc welding using an arc welding robot, the operator visually confirms the welding execution status and bead overview during arc welding, and finely adjusts the standard values of the welding condition parameters to improve welding quality. There are many cases.

  However, in order to finely adjust the standard value of the welding condition parameter, the central processing circuit CPU mounted on the robot control device uses the second increase / decrease signal Ud from the teach pendant TP shown in step (3) above. The step of reading the standard value of the readjustment welding condition parameter input from the communication interface CI2 and reading out the readjustment welding condition parameter standard value from the welding condition storage circuit WM, and the standard value of the readjustment welding condition parameter shown in step (4) is increased or decreased by the increase / decrease signal Ud. It is necessary to process three steps: a step of calculating the fine adjustment value and a step of outputting the fine adjustment value of the readjustment welding condition parameter shown in step (5) to the first communication interface CI1. However, during arc welding, since the central processing circuit CPU gives priority to the control of the robot body, considerable processing power is occupied, and it takes time to process the above three steps with the remaining processing power. End up.

  For this reason, even if the operator quickly changes the increase / decrease signal Ud using the teach pendant TP, it takes time to finely adjust the standard value of the readjustment welding condition parameter transmitted to the welding power supply device PS. Even if Ud changes, the output of the welding power source device PS changes gradually. Therefore, in arc welding for a limited short period of time, arc welding ends before the optimum setting value of the welding condition parameter is obtained according to the workpiece.

  Then, in this invention, it is providing the welding condition setting method of the arc welding robot which can solve the subject mentioned above.

  In order to solve the above-described problem, the first invention transmits a plurality of welding condition parameters from a robot control device to a welding power supply device via a communication path, and performs the above operation based on the received setting values of the welding condition parameters. In a welding condition setting method for an arc welding robot that performs arc welding by controlling the output of a welding power source, one or more readjustment welding condition parameters are selected in advance from the plurality of welding condition parameters, and the readjustment welding is performed. One or a plurality of adjusters corresponding to the condition parameters are provided in the welding power supply device, the set values of the readjustment welding condition parameters are changed by the adjusters, and based on the changed values of the readjustment welding condition parameters A welding condition setting method for an arc welding robot, characterized in that arc welding is performed by controlling output of a welding power source device.

  A second invention is the arc welding robot welding condition setting method according to the first invention, wherein the readjustment welding condition parameter is selected by a teach pendant connected to the robot control device. .

  According to a third aspect of the present invention, the adjuster is replaced with a teach pendant, the teach pendant is connected to the communication path and communicated between the teach pendant and the welding power source, and the readjustment welding is performed by the teach pendant. The welding parameter setting method for an arc welding robot according to the first invention is characterized in that the setting value of the condition parameter is changed.

  4th invention transmits the change value of the said readjustment welding condition parameter from the said welding power supply apparatus to the said robot control apparatus, The arc welding in any one of 1st invention-3rd invention characterized by the above-mentioned This is a welding condition setting method for a robot.

  According to the first invention, one or a plurality of readjustment welding condition parameters are selected from a plurality of welding condition parameters transmitted from the robot controller, and an adjuster corresponding to the readjustment welding condition parameters is welded. Since the standard value of the readjustment welding condition parameter is changed by this adjuster provided in the power supply unit, an increase / decrease signal is input from the teach pendant, and the standard value of the readjustment welding condition parameter is read from the welding condition storage circuit. Because it is not necessary to calculate the fine adjustment value by increasing / decreasing the value according to the increase / decrease signal value, the change can be shortened, and the welding condition parameter setting value suitable for the workpiece during arc welding for a limited short time Can be requested.

  According to the second invention, one or more readjustment welding condition parameters are selected by the teach pendant from the plurality of welding condition parameters transmitted to the welding power supply device, and the selected readjustment welding condition parameters are selected. Since the standard value is changed by the adjuster, it is possible to remotely select and shorten the change.

  According to the third aspect, one or more readjustment welding condition parameter change values are set by the teach pendant from among the plurality of welding condition parameters transmitted to the welding power source device, and the central processing circuit is used. Therefore, since the set change value is directly transmitted to the welding power source device via the communication path, the standard value of the readjustment welding condition parameter can be changed from a remote location.

  According to the fourth aspect, since the change value of the readjustment welding condition parameter is transmitted from the welding power supply device to the robot control device, the transmitted change value is displayed on the display of the robot control device, and the important change value is displayed. Can be stored as standard values of new welding condition parameters.

[Embodiment 1]
FIG. 1 is a detailed view of a welding power source apparatus according to Embodiment 1 of the present invention. In the figure, components having the same reference numerals as those in the detailed view of the conventional welding power source apparatus shown in FIG. 9 perform the same operations, and thus description thereof will be omitted. Only components having different reference numerals will be described. Further, the system configuration diagram of the arc welding robot and the detailed view of the robot control device are the same as those of FIGS.

  In the welding power supply apparatus PS shown in FIG. 1, the third communication interface C13 receives the welding condition parameter signal Wp via the communication path. The readjustment welding condition storage circuit AM inputs the welding condition parameter signal Wp from the third communication interface C13 and stores the standard value of the welding condition parameter. Here, it is assumed that the welding condition parameter signal Wp is formed from the short-circuit current ramp time setting signal T1, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir. The selection circuit CE outputs a selection signal Ce for selecting one of the welding condition parameter signals Wp as a readjustment welding condition parameter. Here, the case where the short-circuit current ramp time setting signal T1 is selected as the readjustment welding condition parameter will be described. The multi-select circuit SE receives the short-circuit current ramp time setting signal T1, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir, and is selected as the readjustment welding condition parameter by the selection signal Ce. The short-circuit current ramp time setting signal T1 is output to the adder circuit AD, and the other three signals Is, Vr, and Ir are output to the main control circuit SC.

  The regulator RE (for example, a variable resistor) shown in FIG. 1 outputs a positive increase / decrease signal Re when the center of the adjustment volume is zero, and when it is turned to the right, a negative increase / decrease signal Re when it is turned to the left. The addition circuit AD outputs a fine adjustment signal Ad obtained by adding the increase / decrease signal Re set by the adjuster RE to the short-circuit current ramp time setting signal T1 which is the readjustment welding condition parameter selected by the multi-select circuit SE. The main control circuit SC controls the output of the main power supply circuit INV based on the fine adjustment signal Ad, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir.

  When the operator performs fine adjustment of the welding condition parameters, the following is performed. The operator selects a readjustment welding condition parameter to be finely adjusted by the selection circuit CE from among a plurality of welding condition parameters. In the above case, the short-circuit current ramp time setting signal T1 is selected as the readjustment welding condition parameter. Next, the welding state is observed while welding, and the adjuster RE is adjusted so that the welding state becomes good. By adjusting the regulator RE, the short-circuit current ramp time setting signal T1 is finely adjusted from the standard value. The standard value is a value stored in the robot controller. Therefore, in the present embodiment, at the time of fine adjustment, there is no need to perform the central processing circuit CPU and communication processing of the robot controller as in the prior art, so that fine adjustment can be performed quickly and with good responsiveness.

“Embodiment 2”
2 is a system configuration diagram of an arc welding robot according to a second embodiment of the present invention, in which the same reference numerals other than TP, WRS, and PS in the system configuration diagram of the conventional arc welding robot shown in FIG. Since the constituents in FIG. 1 perform the same operation, description thereof will be omitted, and constituents of TP, WRS, and PS will be described. FIG. 3 is a detailed view of a welding power source apparatus according to Embodiment 2 of the present invention. In the same figure, circuits with the same reference numerals other than CI3, AM and SE in the detailed view of the welding power source apparatus according to Embodiment 1 of the present invention shown in FIG. The circuit with the symbol is described.

  In the system configuration diagram of the arc welding robot shown in FIG. 2, the robot control device WRS transmits standard values of a plurality of welding condition parameters to the welding power supply device PS via the communication path as welding condition parameter signals Wp. The welding power supply device PS receives the welding condition parameter signal Wp and controls the output of the main power supply circuit INV based on the standard value of the welding condition parameter.

  In the system configuration diagram of the conventional arc welding robot shown in FIG. 7, an increase / decrease signal Ud for finely adjusting the standard value of the readjustment welding condition parameter is set by the teach pendant TP. In the embodiment of the present invention shown in FIG. 2, instead of setting the increase / decrease signal Ud by the teach pendant TP, a welding condition selection signal for selecting a readjustment welding condition parameter to be finely adjusted from a large number of welding condition parameters. Set Ts. The robot control device WRS transmits a welding condition parameter selection signal Ws for selecting a readjustment welding condition parameter based on the welding condition selection signal Ts to the welding power supply device PS via the communication path.

  In the welding power supply apparatus PS shown in FIG. 3, the third communication interface C13 receives the welding condition parameter signal Wp and the welding condition parameter selection signal Ws via the communication path. The readjustment welding condition storage circuit AM inputs the welding condition parameter signal Wp from the third communication interface C13 and stores the standard value of the welding condition parameter. Here, it is assumed that the welding condition parameter signal Wp is formed from the short-circuit current ramp time setting signal T1, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir. Here, the case where the short-circuit current ramp time setting signal T1 is selected as the readjustment welding condition parameter will be described. The multi-select circuit SE receives a short-circuit current ramp time setting signal T1, a short-circuit current suppression value setting signal Is, a welding voltage setting signal Vr, and a welding current setting signal Ir, and inputs welding condition parameters from the third communication interface C13. The short-circuit current ramp time setting signal T1 selected as the readjustment welding condition parameter by the selection signal Ws is output to the adder circuit AD, and the other three signals Is, Vr and Ir are output to the main control circuit SC.

  When the operator performs fine adjustment of the welding condition parameters, the following is performed. The operator selects a readjustment welding condition parameter to be finely adjusted from the plurality of welding condition parameters using the teach pendant TP. In the above case, the short-circuit current ramp time setting signal T1 is selected as the readjustment welding condition parameter. Next, the welding state is observed while welding, and the adjuster RE is adjusted so that the welding state becomes good. By adjusting the regulator RE, the short-circuit current ramp time setting signal T1 is finely adjusted from the standard value. Therefore, in the second embodiment, it is not necessary to perform the processing of the central processing circuit CPU of the robot control device at the time of fine adjustment as in the prior art, so that fine adjustment can be performed quickly and with good responsiveness.

[Embodiment 3]
FIG. 4 is a detailed view of a welding power source apparatus according to Embodiment 3 of the present invention. In the same figure, CI3, AM, SE, CE, AD and SC circuits and components indicated by TP will be described. The same reference numerals other than the above are the detailed view of the conventional welding power source shown in FIG. Since the same operation is performed, the description is omitted.

  The robot controller WRS shown in FIG. 4 transmits the standard values of the plurality of welding condition parameters as welding condition parameter signals Wp to the welding power source apparatus PS via the communication path. Instead of connecting to the robot controller WRS, the teach pendant TP is connected to a communication path to communicate between the teach pendant TP and the welding power source PS, and an increase / decrease signal Ud set by the teach pendant TP is transmitted via the communication path. To the welding power source PS.

  In the welding power supply apparatus PS shown in FIG. 4, the third communication interface C13 receives the welding condition parameter signal Wp via the communication path. The readjustment welding condition storage circuit AM inputs the welding condition parameter signal Wp from the third communication interface C13 and stores the standard value of the welding condition parameter. The selection circuit CE outputs a selection signal Ce for selecting one of the welding condition parameter signals Wp as a readjustment welding condition parameter. The multi-select circuit SE receives the short-circuit current ramp time setting signal T1, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir, and is selected as the readjustment welding condition parameter by the selection signal Ce. The short-circuit current ramp time setting signal T1 is output to the adder circuit AD, and the other three signals Is, Vr, and Ir are output to the main control circuit SC.

  The adding circuit AD adds a fine adjustment signal Ad obtained by adding the increase / decrease signal Ud input from the third communication interface C13 to the short-circuit current ramp time setting signal T1 which is the readjustment welding condition parameter selected by the multi-select circuit SE. Output. The main control circuit SC controls the output of the main power supply circuit INV based on the fine adjustment signal Ad, the short-circuit current suppression value setting signal Is, the welding voltage setting signal Vr, and the welding current setting signal Ir.

  When the operator performs fine adjustment of the welding condition parameters, the following is performed. The operator selects the readjustment welding condition parameter to be finely adjusted from the plurality of welding condition parameters by the selection circuit CE of the welding power supply device. In the above case, the short-circuit current ramp time setting signal T1 is selected as the readjustment welding condition parameter. Next, the welding state is observed while performing welding, and an increase / decrease signal Ud is transmitted by pressing the increase button of the teach pendant TP. Then, by adjusting the increase / decrease signal Ud so that the welding state is good, the short-circuit current ramp time setting signal T1 is finely adjusted from the standard value. Therefore, in the fine adjustment of the third embodiment, the fine adjustment value of the readjustment welding condition parameter is transmitted from the teach pendant TP via the communication path without performing the processing of the central processing circuit CPU of the robot controller. Can be fine-tuned quickly and responsively from a remote location.

[Embodiment 4]
FIG. 5 is a detailed view of a welding power source apparatus according to Embodiment 4 of the present invention. In the same figure, CI3, SE, CE, AD, and WRS will be described, and the other parts are the same as the detailed view of the welding power source apparatus according to the first embodiment of the present invention shown in FIG.

  The addition circuit AD shown in FIG. 5 is a fine adjustment signal Ad obtained by adding the increase / decrease signal Re set by the adjuster RE to the short-circuit current ramp time setting signal T1 which is the readjustment welding condition parameter selected by the multi-select circuit SE. Are input to the main control circuit SC and the third communication interface C13. The third communication interface C13 transmits the fine adjustment signal Ad of the input short circuit current ramp time setting signal T1 to the robot controller WRS via the communication path. The robot controller WRS corrects and stores the standard value of the readjustment welding condition parameter according to the value of the received fine adjustment signal Ad. Thereby, the optimum value of the readjustment welding condition parameter finely adjusted in the welding power source apparatus PS can be stored in the robot control apparatus WRS.

It is detail drawing of the welding power supply device which concerns on Embodiment 1 of this invention. It is a system block diagram of the arc welding robot of Embodiment 2 of this invention. 6 is a detailed view of a welding power source apparatus according to Embodiment 2. FIG. It is detail drawing of the welding power supply apparatus of Embodiment 3 of this invention. It is detail drawing of the welding power supply apparatus of Embodiment 4 of this invention. It is a current waveform of CO2 / MAG welding. It is a system block diagram of the arc welding robot of a prior art. FIG. 8 is a detailed view of the robot control device shown in FIG. 7. It is detail drawing of the welding power supply device shown in FIG.

Explanation of symbols

1, 2 Workpiece 3 Cable 4 Welding wire AD Adder circuit Ad Fine adjustment signal AM Readjustment welding condition storage circuit BL Bus line CE selection circuit Ce selection signal CI1 First communication interface CI2 Second communication interface CI3 Third Communication interface CPU Central processing circuit Ir Welding current setting signal Is Short-circuit current suppression value setting signal PS Welding power supply RE Adjuster (remote control, etc.)
Re Increase / decrease signal SC Main control circuit Sc Main control signal SE Multi-select circuit SW Feeder drive circuit Sw Wire feed drive signal S1 Drive signal TH Welding torch TP Teach pendant Ts Welding condition selection signal T1 Short-circuit current ramp time setting signal Ud Increase / decrease Signal Vr Welding voltage setting signal WC Robot drive circuit Wc Robot drive signal WF Wire feeder WM Welding condition memory circuit WR Robot main body WRS Robot controller Wp Welding condition parameter signal Ws Welding condition parameter selection signal

Claims (4)

  An arc welding robot that transmits a plurality of welding condition parameters from a robot controller to a welding power source device via a communication path, and performs arc welding by controlling the output of the welding power source device based on the received setting value of the welding condition parameter In this welding condition setting method, one or a plurality of readjustment welding condition parameters are selected in advance from the plurality of welding condition parameters, and one or a plurality of adjusters corresponding to the readjustment welding condition parameters are added to the welding. Provided in the power supply device, changing the set value of the readjustment welding condition parameter by the adjuster, and performing arc welding by controlling the output of the welding power supply device based on the change value of the readjustment welding condition parameter A method for setting welding conditions for an arc welding robot.   The welding condition setting method for an arc welding robot according to claim 1, wherein the readjustment welding condition parameter is selected by a teach pendant connected to the robot controller.   Instead of the adjuster, the teach pendant is connected to the communication path to communicate between the teach pendant and the welding power source, and the setting value of the readjustment welding condition parameter is changed by the teach pendant. The welding condition setting method for an arc welding robot according to claim 1. The welding condition setting of the arc welding robot according to any one of claims 1 to 3, wherein a change value of the readjustment welding condition parameter is transmitted from the welding power supply device to the robot control device. Method.

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