JP2545379B2 - Welding robot controller - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding robot, and more particularly to a controller for a welding robot suitable for preventing deterioration of welding quality due to automatic recovery processing when a welding abnormality occurs.

[Conventional technology]

In the conventional welding robot, the robot stopped due to the occurrence of welding abnormalities such as wire welding and arc breakage, and the worker made a mark on the relevant part of the work to instruct the continuation of the work. Recently, there are welding robots with an automatic recovery function for welding abnormalities for the purpose of improving the operating rate.When a welding abnormality occurs, recovery processing is automatically performed to prevent a decrease in the operating rate and to count the number of welding abnormality occurrences. ing.

[Problems to be solved by the invention]

The above-mentioned prior art is mainly intended to prevent the deterioration of the operating rate by the automatic recovery processing of the welding abnormality, and does not pay much attention to the prevention of the welding quality deterioration due to the automatic recovery processing when the welding abnormality occurs.

An object of the present invention is to provide a welding robot control device capable of simplifying automatic / manual determination of welding quality in a later step by totalizing and storing the contents of welding abnormalities that have occurred in time series.

[Means for solving problems]

The above purpose is to detect welding abnormalities in the welding robot control device that controls welding robots with a function to detect welding abnormalities such as wire welding and arc breaks, as well as adding means for collecting and recording welding abnormal data during work. Each time, a welding abnormality data table that records desired contents such as the cause and location of the abnormal data at that time is provided in a time series, and the recorded contents are output from the welding abnormality data table in response to a request. It is achieved by displaying.

[Action]

In the welding robot controller, when a welding abnormality occurs during work, the robot stops and the welding machine sends the factors such as wire welding and arc breakage. The desired contents such as the program (work) number of the work currently being executed, the step number, the coordinates of the occurrence position, the occurrence time, etc. are stored in the welding abnormality data table in time series in accordance with the size of the data table, and the request is made. It is used to judge the welding quality in the subsequent process by displaying the output according to the above. When one welding abnormality occurs, the address pointer of the above welding abnormality data table is incremented by 1 to indicate the next address. However, if the occurrence frequency of welding abnormality is high, there is something wrong with the robot program or work. Since the size of the welding abnormality data table is limited to storing 100 data, for example, if the address pointer is incremented from 0 to 99 and becomes 0, an appropriate size will suffice. Target.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

First, FIG. 2 is a system configuration diagram of a standard welding robot showing an embodiment of a controller for the welding robot according to the present invention. In FIG. 2, 1 is a robot controller, 2 is a teach pendant, 3 is a welder, 4 is an output device, 5 is a visual device, and 10 is a robot. The robot controller 1 shown in FIG. 2 includes a teach pendant 2, a robot 10, and a welding machine 3.
The output device 4 and the visual device 5 are appropriately connected according to their functions, and the output device 4 is a TV monitor, a printer, or a host computer connected to a serial line. Corresponding to.

In the configuration shown in FIG. 2, the teach pendant 2 connected to the robot controller 1 guides the robot 10 to a predetermined position, teaches a series of operation data together with various conditions such as welding information, and then enters an actual playback. When the actual welding operation by the welding machine 3 is started, a welding abnormality may occur due to some defective factors such as a defect in the teaching content and a defective work. There are several factors such as wire welding, arc breaks, and cooling water breaks as factors that cause welding abnormalities due to these actual welding operations, and these factors are transferred to the robot controller 1 via the welder 3 and appropriately Perform the necessary processing.

Conventionally, in general, the robot 10 was stopped, and the operator was informed of the occurrence of the welding abnormality and left the cancellation process.
However, this method requires an operator to intervene every time a welding abnormality occurs, which is completely troublesome from the viewpoint of automation.
For this reason, recently, a welding robot equipped with an automatic recovery function when a welding abnormality occurs is being adopted. According to a welding robot with this type of automatic recovery function, automatic recovery by wire welding and arc break retry will work.
Although there is an advantage that the operation rate can be kept to a minimum because the work can be continued without the intervention of an operator, it is not possible to clearly identify the location of the abnormal welding due to the automatic recovery, and there are problems in terms of quality judgment. there were. Therefore, according to the present invention, a welding abnormality data table is newly set in the robot controller 1, and the necessary contents are stored in this table each time a welding abnormality occurs.

FIG. 1 is a table configuration diagram of a welding abnormality data table provided in the robot control device 1 of FIG. First
In the figure, 6 is a welding abnormality data table.

FIG. 1 shows the contents stored in the welding abnormality data table 6 for each welding abnormality. The contents are the cause code, the generation time, the program (work) number, the point (step) number, and the generation position ( Coordinates). There are several types of causes for these welding abnormalities, but various factors are stored in the welding abnormality data table 6 as codes inside the robot controller 1. Examples of the correspondence between the factor code and the factor type are, for example, code 0 is stop during welding, code 1 is wire welding, code 2 is arc break, and code 3 is
Is torch contact, code 4 is out of cooling water, code 5 is low in gas pressure, code 6 is out of wire, code 7 is others. It should be noted that these cause codes and their contents are configured so that the user can arbitrarily set them by adding, deleting or changing them.

FIG. 3 is a flow chart of a process of storing in the welding abnormality data table 6 of FIG. 1 (FIG. 2). In FIG. 3, a process 100 performs a cause code process, a process 101 performs an occurrence time process, and a process 102 executes a program (work).
The number is stored, the process (103) stores the point (step) number, the process 104 stores the occurrence position (coordinate), and the process 105.
Determines whether the address pointer AP is maximum (AP = 99), and if not, updates the address pointer AP in process 106 (A
P = AP + 1), if maximum, address pointer in process 107
Initialize the AP (AP = 0).

The information stored in the welding abnormality data table 6 of FIG. 2 (FIG. 3) can be selected according to the system configuration of the welding robot and the size of the welding abnormality data table 6, and is not shown in the drawing. At the beginning of each storage process in the figure, a flag determination as to whether or not to perform the storage process is performed.
The system designer or the user can freely set these flags. Further, the larger the size of the welding abnormality data table 6 is not the better, and the fact that the frequency of welding abnormality occurrences is high implies that there is a problem with either the welding machine 3 or the workpiece as taught by the robot 10. It is preferable to set an appropriate size. In this embodiment, 100 pieces of welding abnormality information are prepared and the address pointer A
When P becomes maximum, only the address pointer is initialized to form the chain-shaped data table 6 so that the latest 100 welding abnormality contents can be always stored. The size of the table 6 can be arbitrarily set by the user as long as the memory permits.

4 and 5 are explanatory views showing display examples in which the contents of the welding abnormality data table 6 of FIG. 1 are displayed on the output device 4 of FIG. 2, respectively. Fig. 4 shows the contents of welding abnormal data in time series for all data. The displayed contents are code number, its factor, time, program number (work name), point number and coordinate X, Y, Z values. And so on. If the display is not required, the display content is omitted. Fig. 5 is an example in which the contents of the welding abnormality data are also edited and displayed according to the cause of occurrence. The displayed contents are code numbers, program numbers (work name) and points according to factors such as wire welding, arc breakage and torch contact. Such as a number.
When an abnormality occurs at the same point of the same work as shown in the item of wire welding in the display example of FIG. 5, the teaching data or the display data can be easily determined whether the work is defective or not.

Note that the welding abnormality occurrence position (coordinates) X, which is displayed in Fig. 4,
If Y, Z, etc. is a host computer connected to the output device 4 via a communication line, use it as information such as showing the work shape on the graphic terminal and the welding abnormality occurrence position (coordinates). You can also

It is also apparent that if the robot control device 1 has a function of displaying the work shape and the operation position of the robot 10, the welding abnormality occurrence position can be easily illustrated correspondingly. Furthermore, if there is a process such as automatic determination of welding quality by the visual device 5 in the subsequent process, the data of the welding abnormality occurrence position can be effectively used as position information for that process.

〔The invention's effect〕

According to the present invention, it is possible not only to see the cause of welding abnormality in time series, but also to easily see the program number (work name), point number, etc. when the abnormality occurs, so that the welding quality can be determined. In addition to being easy, the abnormal welding position (coordinates) can be stored, so that it can be used for the graphical display of the occurrence location and the automation of quality judgment by a visual device, and a great effect can be expected.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a welding abnormality data table showing an embodiment of a welding robot control device according to the present invention, FIG. 2 is a system configuration diagram of the welding robot, and FIG. 3 is FIG. 1 (FIG. 2). The processing flowchart of FIG. 4 and FIGS. 4 and 5 are explanatory views of the display example of FIG. 1 (FIG. 2). 1 ... Robot control device, 2 ... Teaching pendant, 3 ... Welder, 4 ... Output device, 5 ... Visual device,
6 ... Welding error data table, 10 ... Robot.

Claims (1)

(57) [Claims] Claim: What is claimed is: 1. A welding robot control device which controls a welding robot having means for detecting welding abnormalities such as wire welding and arc breakage, and additionally includes means for collecting and recording welding abnormal data during work. Each time an error is detected, a welding error data table is provided to record the desired cause such as the cause and location of the abnormal data at that time in a time series, and the recorded contents are output from the above welding error data table upon request. A control device for a welding robot, characterized in that it is configured to be displayed.