JPH03114669A - Welding machine control system by robot - Google Patents

Abstract

PURPOSE:To carry out every action of a welding machine by a robot controller and to improve operability by setting every parameter required for welding on the controller and controlling the welding machine. CONSTITUTION:Various parameters for welding are set on the controller 10 and when welding instructions are inputted to the controller, gas is discharged from the welding machine 30. After the lapse of pre-flow time, the welding machine 30 is then operated at the welding voltage and the wire feed rate at the time of line. When an arc signal is inputted from the welding machine 30, a robot 20 is then started to operate and the welding machine 30 is operated at the set welding voltage and wire feed rate at the time of arc welding. When a welding stop command is inputted, the controller 10 stops operation of the robot 20 and changes over to the welding voltage and the wire feed rate at the time of crater and after the lapse of crater time, the wire feed rate is diminished to zero and the set burn-back time welding voltage is changed over to the burn-back voltage and after the lapse of set post-flow time, the gas discharge from the welding machine 30 is stopped and welding is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a welding robot, and more particularly to a welding machine control system for controlling a welding machine by a robot control device.

In conventional arc welding, at the start of welding, the welding voltage during arc welding is set to allow carbon dioxide gas to flow out and then to smooth the welding start-up.

A run-in process is performed in which the welding machine is operated at a higher welding voltage and wire feed speed than the wire feed speed (welding current), and when an arc occurs, welding is performed at the set welding voltage and wire feed speed for arc welding. I do. If the welding voltage and wire feed speed are stopped immediately at the end of welding, a crater-shaped hole will be created in the welding beat. Therefore, after reducing the welding voltage and wire feed speed and carrying out welding for a predetermined period of time, a crater treatment is performed. Burnback processing is performed by stopping wire feeding and applying voltage for an appropriate period of time to prevent the wire and workpiece from welding.

Conventionally, in known welding robots, during welding,
The robot control device simply outputs a welding start command to the welding machine, as well as the set welding electric welding and wire feed speed during arc welding, and the welding machine performs the above run-in process and starts welding. The structure is as follows. Furthermore, when welding is finished, the robot controller simply outputs a welding stop command to the welding machine and stops outputting the welding voltage and wire feed speed, and the welding machine performs the crater processing and burn pack processing described above. It is configured to stop welding.

Problems to be Solved by the Invention As mentioned above, in conventional welding robots, run-in processing, crater processing, and burnback processing are performed on the welding machine side, and various parameter settings for performing these processing are required. must be set in the welding machine, and all matters related to welding operations, including robot operations, cannot be set in one place on the robot control device side. Also,
A simple welding machine that cannot perform the above-mentioned run-in processing, crater processing, and burnback processing on the welding machine side has the disadvantage that automatic welding by a robot cannot be performed.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a welding control method using a robot, in which the setting values of all parameters necessary for welding are set on the robot control device side, and the welding operation of the welding machine can be controlled on the robot control device side. It is in.

Means for Solving the Problems In the present invention, preflow time, run-in time, welding voltage and wire feed speed during run-in, crater time, welding voltage and wire feed speed during crater, and burnback are stored in the robot control device in advance. time, voltage during burnback,
The boss flow time, welding voltage and wire feed speed during arc welding are set, and when a welding command is input to the robot control device from a teaching program or the like, the robot control device outputs a gas signal to the welding machine. When the welding machine receives this gas signal, it releases the gas. Then, the robot control device outputs the set welding voltage and wire feed speed during run-in after the set briflow time has elapsed, and the welding machine starts operating at the received welding voltage and wire feed speed during run-in. and performs run-in processing. When an arc occurs, the welding machine outputs an arc generation signal to the robot controller.
When this signal is input, the robot controller starts operating the robot, and when the set run-in time has elapsed, the robot controller outputs the set welding voltage and wire feed speed during arc welding. Operate the welding machine at the welding voltage and wire feed speed for arc welding. After that, when a welding stop command is input, the robot control device stops the operation of the robot and switches the welding voltage and wire feed speed to the welding voltage and wire feed speed for the set crater time to perform crater processing. Then, when the set crater time has elapsed, the robot control device reduces the wire feed speed output to zero, switches the welding voltage to burnback voltage for the set burnback time, and outputs it, causing the welding machine to perform burnback processing. After the set post-flow time has elapsed, the robot controller stops the gas signal, stops the gas from flowing out of the welding machine, and ends the welding.

Embodiment FIG. 1 is a block diagram of main parts of a welding robot implementing an embodiment of the present invention.

In the figure, reference numeral 10 is a control device such as a numerical control device that controls the robot, and the control device 10 is a processor (hereinafter referred to as C
RAM 13.PU) 11, which stores control programs in the cpUll; ROMI 2; RAM 13.RAM 13.RAM 13.RAM 20, which stores teaching programs for the operations of the robot 20 taught by the teaching operation panel 14, etc.; and is used for various calculations. Teaching operation panel 1
4. Manual data entry device with CRT display (CRT/
MDI)15. An axis controller 16 that controls a servo circuit 18 of a servo motor for each axis of the robot 20 and an interface 17 are connected by a bus 19. Also,
Welding machine 30 is connected to the robot controller via interface 17.

Note that the configuration of the welding robot described above is conventionally known, and details thereof will be omitted.

However, the welding machine 30 is only driven based on the welding voltage and wire feeding speed sent from the robot control device 1°, and the welding machine itself does not perform run-in processing or cratering. This is a simple welding machine that does not control processing, burnback processing, etc.

Next, various parameter settings for welding will be described.

First, change the screen of CRT/MD I 1.5 to the parameter setting screen and press the soft key "YOCERA".
The screen displays the welding voltage during arc welding as shown in Figure 2 (a),
The wire feeding speed setting screen will appear.

Note that there is a predetermined relationship between wire feeding speed and welding current.
The welding current CMA becomes the wire feeding speed.

Then, the displayed welding voltage CMV, welding current (wire feed speed) CMA combination number N000 to N00.
Select one from 3, set the number, and press the soft key ""AS". The CRT screen will appear as shown in Figure 2 (b).
The screen changes to The feedback column in FIG. 2(a) shows the welding voltage and welding current sent from the welding machine when the welding machine actually starts operation.

The screen in FIG. 2(b) is a parameter setting screen for run-in processing, etc. at the start of welding, and numbers N0OO to N0O3 indicate preflow time and run-in time.

Welding voltage CMV during run-in, welding current during run-in (
Wire feed speed) CMA combinations are displayed, select and set one number from among these, and press the soft key “CRAT”.
When ER'' is pressed, the CRT screen changes to the one shown in FIG. 2(c).

The screen in Figure 2 (C) is a setting screen for parameters related to crater treatment, including crater time, welding voltage C at the time of crater.
The combination of MV, welding current (wire feed speed) CMA is N
Displayed as 0OO~N0O3, select and input one number from among them, set parameters for crater processing,
When the soft key "BBCK" is pressed, the screen changes to the one shown in FIG. 2(d). The screen in Fig. 2(d) is the screen for setting the parameters and post flow time of the balloon back process, and the combinations of burn back time, welding voltage CMV during burn back, and post flow time are numbers N000 to N003.
By selecting and inputting one number from among them, the burnback processing parameters and postflow time are set.

In this way, all parameters necessary for the welding operation are set.

FIG. 3 is a flowchart of welding machine control processing by the robot control device during welding operation, and FIG. 4 is a timing chart at this time.

When the robot is operated based on the teaching program and a welding command AS is input from the teaching program, the CPU II of the robot control device 10 outputs a gas signal WDO2 to the welding machine 30 via the interface 17, and the signal is set in the timer T1. A preflow time (see FIG. 2(b)) is set, and a timer T1° is started (step SL).

When the welding machine 30 receives this gas signal WDO2, it starts flowing out carbon dioxide gas (see FIG. 4). On the other hand, CPU
1l determines whether or not the timer T1 has timed up, and when the timer T1 has timed up, it outputs a welding start command WDOI to the welding machine 30, and also outputs the set run-in welding voltage CMV.
(This voltage is indicated as CMVR in Figs. 3 and 4) and welding current (wire feeding speed) CMA (This value is indicated as CMAR in Figs. 3 and 4).

Then, the run-in time set in the timer T2 is set and started (steps 82 to S4). As shown in Figure 4, the welding voltage CMV during arc welding is higher than the welding current (wire feeding speed) CMA.

A current will be output, and the welding machine 30 will output this run-in welding voltage CMVR and welding current (wire feeding speed) CM.
It will be driven by Ak. Then, when an arc occurs, the welding machine 30 detects it, outputs an arc occurrence signal WD I 2 to the control device 10, and outputs an arc occurrence signal WD I 2 to the control device 10.
When I1 detects this arc generation signal WDI2, it starts the operation of the robot and drives and controls the robot according to the teaching program (steps S5, S56) (see FIG. 4').

Next, the CPU 11 determines whether or not the timer T2 has timed up, and when the set run-in time has elapsed, the welding voltage and welding current (wire feeding speed) are set to the welding voltage CMV and the welding current during arc welding. Switching to CMA (steps S7 and S8), the welding machine 30 thereafter uses the switched welding voltage AMV.

Driven by welding current (wire feeding speed) CMA.

The robot operates according to the teaching program, welding is performed, the welding is completed, and the welding stop command A is issued from the teaching program.
When E is read (step S9), 1 CPU 1 stops the robot operation at step 510.
), the welding voltage, the crater voltage at which the welding current is set (in Figures 3 and 4, this crater voltage is indicated as CMVC), the welding current (wire feeding speed) (in Figures 3 and 4, CMAC), sets the crater time set in the timer T3, and starts the timer T3 (steps 811, 512).

As a result, the welding voltage and wire feeding speed of the welding machine 30 are reduced as shown as CMVC and CMAC in FIG. 4, thereby preventing the generation of craters.

When the crater time set in the timer T3 expires, the CPU 1.1 turns off the welding start command WDOI and changes the welding voltage to the set burnback voltage CMVB.
, and the welding current, that is, the wire feeding speed, is set to "0".
'', set the burnback time set in timer T4 to the postflow time set in timer T5, and start timers T4-T5 (steps 813 to 5).
15). As a result, the arc between the wire and the workpiece disappears, and the arc generation signal WD I 2 turns off as shown in FIG. Also, since the burnback voltage is low, it prevents the wire from welding to the workpiece.

Next, the CPU 11 determines whether or not the timer T6 has timed up, and when the set burnback time has elapsed and the timer T has timed up, the burnback voltage CMVB
is set to "0", then it is determined whether the postflow time set in timer T5 has elapsed, and if it has elapsed,
Turn off the gas signal WDO2 to stop the outflow of carbon dioxide gas,
Finish welding.

Effects of the Invention The present invention can be applied to a simple welding machine that does not have a control device for controlling run-in processing, burnback processing, etc. in the welding machine itself, by controlling the welding machine with a robot control device and performing the above-mentioned method. It has also been made possible to perform automatic welding by robots. Further, operations for the robot and the welding machine need only be performed with respect to one robot control device, improving operability.

3

[Brief explanation of drawings]

FIG. 1 is a block diagram of the configuration of a welding robot that implements an embodiment of the present invention, and FIGS. FIG. 3 is a flowchart of welding processing in the same embodiment, and FIG. 4 is a timing chart in the same embodiment. 10... Robot control device, AS... Welding command,
AE...Welding stop command, WDO2...Gas signal, W
DOI...Welding start command, CMV...Welding voltage, C
MA...Welding current (wire feeding speed), WD I 2
...Arc occurrence signal. 4

Claims (1)

[Claims] Preflow time, run-in time, welding voltage and wire feed speed during run-in, crater time, welding voltage and wire feed speed during crater, burnback time, voltage during burnback, postflow time, and The welding voltage and wire feed speed during arc welding are set, and when a welding command is input to the robot control device, the robot control device outputs a gas signal to the welding machine, causes the gas to flow out from the welding machine, and completes the settings. After the specified preflow time has elapsed, the welding voltage and wire feed speed set during run-in are output, the welding machine is operated at the welding voltage and wire feed speed during run-in, and an arc generation signal is input from the welding machine. When the set run-in time has elapsed, the robot outputs the set welding voltage and wire feed speed for arc welding, and returns the welding machine to the normal welding voltage and
When the robot is operated at the wire feed speed and a welding stop command is input, the robot control device stops the robot operation and switches the welding voltage and wire feed speed to the welding voltage and wire feed speed at the set crater time. When the set crater time has elapsed, the wire feed speed output is set to zero, the set burnback time welding voltage is switched to the burnback voltage, and the gas signal is stopped after the set postflow time has elapsed. A welding machine control system using a robot, which is characterized by stopping gas outflow from the welding machine.