JPH08238571A - Controller of welding robot - Google Patents

Abstract

PURPOSE: To provide a controller of welding robot capable of time sequentially summing up/storing contents of weld abnormality generated and simplifying manual/automatic discrimination of welding quality at succeeding process. CONSTITUTION: A welding data table 6, on which, at every time weld abnormality is detected, the cause to generate weld abnormality is recorded, is provided, as required, the abnormality data is displayed for each cause or each position. By this method, the cause to generate weld abnormality is observed in time sequence as well as for program number (work name), point number, etc., at generating abnormality as required, the discrimination of welding quality is made easy, further, because position of weld abnormality (coordinate) is stored, graphic display of generated place and automation of quality discrimination are made possible.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding robot, and more particularly, to a welding robot control apparatus suitable for preventing deterioration of welding quality due to automatic recovery processing when a welding abnormality occurs. Regarding 2. Description of the Related Art In a conventional welding robot, when a robot stops due to an abnormality (alarm) such as wire welding or arc breakage during welding operation, an operator marks a relevant portion of a work and Was instructed to continue. Further, recently, there is a welding robot to which an automatic recovery processing function for welding abnormality is added for the purpose of improving the operation rate. The number of occurrences of welding abnormalities is being counted along with the reduction. [0004] The above prior art is mainly intended to prevent the deterioration of the operating rate due to the automatic recovery processing of the welding abnormality, and to prevent the deterioration of the welding quality due to the automatic recovery processing when the welding abnormality occurs. There is not much consideration for it. An object of the present invention is to provide a controller for a welding robot capable of simplifying automatic / manual determination of welding quality in a subsequent process by totalizing and storing the contents of welding abnormalities that have occurred in time series. It is in. [0006] The above object is to control a welding robot having a function of detecting a welding abnormality such as wire welding and arc breakage, and to have a function of collecting and recording welding abnormality data during work. In the added welding robot control device, prepare a welding abnormality data table that records the content such as the cause and location of the welding abnormality data in a time series, and whenever desired, import the desired data, This is achieved by sequentially storing the data in the data table and displaying the data separately according to the request. In a welding robot controller, when a welding abnormality occurs during work, the robot stops and the welding machine sends a factor for generating welding abnormality data such as wire welding or arc breakage. In addition to the cause of the abnormal data, the desired contents such as the program (work) number of the work currently being executed, the step number, the coordinates of the position where the error occurred, and the time at which the error occurred corresponded to the size of the data table. It is stored in a table and is output and displayed in response to a request, so that it can be used for the determination of welding quality in a later process. At this time, when one welding abnormality occurs, the address pointer of the above-mentioned welding abnormality data table is incremented by 1 to indicate the next address. However, if the occurrence frequency of welding abnormality is high, it may occur in the robot program or the work. Since it is possible that there is a defect, the size of the welding abnormality data table is limited to, for example, 100 pieces of data storage, and if the address pointer is incremented from 0 to 99 one by one Suitable size,
It is practical. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A welding robot control apparatus according to the present invention will be described in detail below with reference to illustrated embodiments. First, FIG. 2 shows an example of an embodiment in which a robot controller according to the present invention is applied to a standard welding robot. In this figure, 1 is a robot controller and 2 is a robot controller.
Is a teaching pendant, 3 is a welding machine, 4 is an output device, 5 is a visual device, and 10 is a robot. The teaching pendant 2, the robot 10 and the welding machine 3 are necessarily installed in the robot controller 1, but the output device 4 and the visual device 5 are appropriately installed according to the required functions. Output device 4 here
Corresponds to a TV monitor, a printer, a high-order computer connected to a serial line, or the like. In the configuration shown in FIG. 2, the teaching 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 plays back. When the welding operation is started by the welding machine 3, welding abnormalities may actually occur due to some defective factors such as a defect in the teaching contents and a defective work. There are several factors that cause welding abnormalities in these actual welding operations, such as wire welding, arc breaks, and cooling water breaks. When abnormalities occur, data representing these factors is used by the welder 3 The data is transferred to the robot control device 1 via the, and the necessary processing is performed appropriately. Conventionally, generally, the robot 10 is stopped and at the same time, the operator is informed of the occurrence of the welding abnormality and left the cancellation processing. However, in this method, as described above, a worker must intervene every time a welding abnormality occurs,
It was far from the point of view of automation. For this reason, recently, as also described above, a welding robot equipped with an automatic return function when a welding abnormality occurs is being adopted. According to a welding robot having this type of automatic return function, There is an advantage that the welding work can be continued without the intervention of the worker by automatically canceling the welding and automatically returning by the retry of the break of the arc, and the decrease in the operating rate can be minimized. However, in this method, since the welding is automatically restored, there is a problem in terms of quality judgment such that the abnormal welded portion is not clearly identified. Therefore, in the present invention, a welding abnormality data table is newly set in the robot control device 1, and the abnormality data of necessary contents is stored in the welding abnormality data table whenever the welding abnormality occurs. FIG. 1 is a table configuration diagram of a welding abnormality data table provided in the robot controller 1 of FIG. 2. In the figure, 6 is a welding abnormality data table. In FIG. 1, the contents stored in the welding abnormality data table 6 for each welding abnormality are enlarged and shown.
As shown in the figure, the cause code, occurrence time, program (work) number, point (step) number, and occurrence position
(Coordinates) etc. As described above, although there are several causes of these welding abnormalities, the various factors are stored in the welding abnormality data table 6 inside the robot controller 1 as codes. Examples of the correspondence between the factor code and the factor type are, for example, code 0 is a stop during welding, code 1 is wire welding, code 2 is an arc break, code 3 is a torch contact, code 4 is a cooling water break, Code 5 has a decrease in gas pressure, code 6 has a broken wire, and code 7 has other factors. Note that these factor codes and their contents are configured so that the user can arbitrarily add, delete, or change them and set them. Next, FIG. 3 is a flow chart showing the storage processing in the welding abnormality data table 6 by the robot control device 1. In the processing 100, the cause code processing is performed, in the processing 101, the occurrence time processing is performed, and in the processing 102. The program (work) number is stored, the point (step) number is stored in process 103, and the generation position (coordinate) is stored in process 104. In process 105, it is determined whether the address pointer AP is maximum (AP = 99). If not, process 106
The address pointer AP is updated at (AP = AP + 1), and if the maximum, the address pointer AP is initialized at processing 107 (AP = 0). The information stored in the welding abnormality data table 6 is configured so that it can be selected and selected depending on the system configuration of the welding robot and the scale of the welding abnormality data table 6, and although not shown, each storage in FIG. A process for determining whether or not the storage process is to be performed is added to the beginning of the process, and the system designer or user can freely set these flags. At this time, the welding abnormality data table 6
The larger size is not the better, and the fact that the occurrence frequency of welding abnormalities is high implies that there is a problem with the teaching content of the robot 10 or the welder 3 or the work, and an appropriate size is set. Preferably. Therefore, in this embodiment, 100 pieces of welding abnormality information are prepared, and when the address pointer AP becomes maximum, only the address pointer is initialized, so that the chain-shaped data table 6 is formed. Formed,
The latest 100 abnormal welding contents are always stored. Note that the size of the table 6 can also be set arbitrarily by the user within a range that can be set in the memory. FIGS. 4 and 5 show display examples when the contents of the welding abnormality data table 6 of FIG. 1 are displayed on the output device 4 of FIG. 2, respectively. This is an example in which the contents of welding abnormal data are displayed in chronological order for all data, and the display contents at this time are code numbers and their causes, time and program numbers (work names), point numbers,
In addition, there are values of coordinates X, Y, and Z that represent the position where the abnormality has occurred. If the display is not required, the display content is omitted. Therefore, when the output device 4 is a host computer connected via a communication line, the welding abnormality occurrence positions (coordinates) X, Y, Z in the display contents of FIG.
It can also be used as information such as showing the shape of the work on the graphic terminal or showing the position (coordinates) where the welding abnormality has occurred. Next, FIG. 5 shows an example in which the contents of the welding abnormality data are similarly edited and displayed according to the generation factors. The display contents are the code numbers according to the factors such as wire welding, arc break, and torch contact, etc. The program number (work name), point number, etc. In the display example of FIG. 5, as shown in the item of wire welding, when an abnormality occurs at the same point of the same work, teaching data or display data by which a defect of the work can be easily determined. It is possible to know the history of abnormalities. Further, if the robot control device 1 has a function of displaying the work shape and the operating position of the robot 10, it is apparent that the welding abnormality occurrence position can be easily illustrated correspondingly. Further, if there is a process such as automatic determination of welding quality by the visual device 5 in a subsequent process, the data of the welding abnormality occurrence position can be effectively used as position information for that process. According to the present invention, the cause of welding abnormality can be seen in time series, and if necessary, the program number (work name) or point number at the time of abnormality occurrence can be easily seen. Therefore, it becomes easy to judge the welding quality and
Since the abnormal welding position (coordinates) can be stored, it can be used for graphic display of the occurrence location and automation of quality judgment by a visual device, and a great effect can be expected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a welding abnormality data table in an embodiment of a controller for a welding robot according to the present invention. FIG. 2 is a system configuration diagram of a welding robot to which the robot controller according to the present invention is applied. FIG. 3 is a flowchart for explaining the operation of an exemplary embodiment of the present invention. FIG. 4 is an explanatory diagram showing an example of a data display according to the embodiment of the present invention. FIG. 5 is an explanatory diagram showing another example of data display according to the embodiment of the present invention. [Explanation of symbols] 1 robot control device 2 teaching pendant 3 welding machine 4 output device 5 visual device 6 welding abnormal data table 10 robot

Claims (1)

[Claims] 1. Every time a welding abnormality is detected, the welding abnormality is detected in the controller of the welding robot that has means for detecting welding abnormality such as wire welding and arc breakage, and means for collecting and recording welding abnormality data. A welding robot control device comprising a welding abnormality data table for recording the factors that have occurred in a time-series manner and displaying the abnormality data for each factor as necessary. 2. Each time a welding abnormality is detected in a welding robot controller equipped with means for detecting welding abnormalities such as wire welding and broken arcs and means for summarizing and recording welding abnormality data, the welding abnormality at that time is detected. A control device for a welding robot, comprising a welding abnormality data table for recording occurrence positions in a time-series manner, and displaying abnormality data by position as necessary.