JP4758019B2 - Automatic operation method of welding robot apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic operation method for a welding robot apparatus that performs a regenerating operation of the next welded joint after an abnormality occurs during the regenerating operation.
[0002]
[Prior art]
Conventionally, as shown in FIG. 3, when machining abnormality is detected during laser machining, laser machining is interrupted (step S3), the machining abnormality occurrence position is stored (step S4), and the laser machining head is retracted a predetermined distance ( Step S5), the machining head is moved backward by a predetermined distance along the machining path that has been executed until the machining abnormality is interrupted (step S6), and the process is carried forward again along the machining path that has been executed to the machining abnormality interruption position (step S9). If the machining abnormality recurs even after retrying the same operation a predetermined number of times after the machining abnormality reoccurs before the machining abnormality occurrence position, skip to the next machining block (step S12) and resume laser processing A method is known (JP-A-6-202722).
[0003]
In this conventional method, a processing block in which a processing abnormality has occurred is retried a predetermined number of times, and if there is no similar processing abnormality, the remaining unprocessed portion can be reliably laser processed, and a retry processing is performed a predetermined number of times. However, if a machining abnormality occurs, unattended operation of the laser machining can be performed without skipping to the next machining block and interposing an operator to cancel the cause of occurrence of the abnormality every time the machining abnormality occurs.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional method, even if skipping to the next processing block after a predetermined number of retry processings, the cause of the processing abnormality has not been eliminated, and the same processing abnormality may reoccur even in the next processing block skipped. In the worst case, there is a problem that many unprocessed processing blocks are generated. In addition, with the conventional method, it is possible to skip to the next machining block and continue machining without intervening the operator to cancel the cause of occurrence of each abnormality, but there is a great deal of repair work in the subsequent process. There is also a problem that it will take a long time.
[0005]
Accordingly, the present invention provides an automatic operation method of a welding robot apparatus that regenerates the next welded joint that has been skipped after eliminating the assumed cause after the occurrence of a welding abnormality, thereby preventing a reoccurrence of the welding abnormality and reducing repair work. The purpose is to provide.
[0006]
[Means for Solving the Problems]
To achieve the above object, claim 1 of the present invention, by generating an arc between the wire and the weld joint fed from the welding torch, sequentially performs welding of the weld joint in a workpiece comprising a plurality of welded joint welding In the automatic operation method of the robot apparatus, during the regenerating operation of the welding robot, the regenerating operation is interrupted when any of the abnormalities of welding tracing abnormality, nozzle contact abnormality, arc abnormality indicating the disappearance of the arc occurs, wherein any of the abnormalities, welding copying abnormality occurs during welding, the nozzle occurred or during touch sensing in the weld contact abnormal, or if the arc is abnormal that occur during welding, generation of the any of the abnormal It determines the presence of the welded joint following the point, if it is determined that the there are any subsequent abnormality occurrence position data welded joint, retracted from the generation position of the one of the abnormality, the welding It is characterized by performing the removal or replacement of the nozzle of the welding torch of deposits adhering to the nozzle of over switch to playback operation for the next welded joint of the welded joint then the one of abnormality has occurred in the Yes.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the welding robot apparatus according to the embodiment of the present invention includes a welding power source 10, a nozzle cleaning device 20 for the welding torch 11, a robot body 30, and a robot control device 40 for the robot body 30. It is made up of. In the welding robot apparatus, a positioner for positioning each welding joint of a workpiece (not shown) (hereinafter abbreviated as a workpiece) within the operation range of the robot body 30 and an appropriate welding posture, and the operation range of the robot body 30. A robot body moving / up-and-down device that expands the range may be included.
[0008]
The welding power source 10 is, for example, of the carbon dioxide shield consumable electrode welding method, and receives a welding start / end command or a welding current / voltage welding condition command from a welding power source control unit 81 (to be described later) of the robot controller 40, and the like. The welding power of the welding welding condition command is supplied to a welding torch 11 and a workpiece provided at a wrist part tip (not shown) of the robot body 30 (not shown). Further, the welding power source 10 detects a welding current during welding and transmits a welding current detection signal (WCR) to a welding power source control unit 81 (to be described later) of the robot control device 40. The welding power source 10 is also used as a sensing power source. In addition, a wire (not shown) (not shown) fed from the welding torch 11 is supplied from a wire feeding device (not shown), and carbon dioxide gas etc. for shielding an arc generated between the wire and the workpiece is shown. It is supplied to the welding torch 11 from an omitted carbon dioxide supply device.
[0009]
The nozzle cleaning device 20 removes spatter and the like (not shown) (hereinafter abbreviated as spatter) attached to the torch nozzle (hereinafter abbreviated as torch nozzle) of the welding torch 11. It is installed within the operating range. The nozzle cleaning device 20 receives a cleaning start / end command from a nozzle cleaning device control unit 82 (to be described later) of the robot control device 40 and performs a cleaning operation when the welding torch 11 is positioned in a cleaning state (not shown). The spatter and the like adhering in the torch nozzle are removed.
[0010]
The robot body 30 is, for example, a 6-axis vertical articulated type, and is provided with a DC motor (not shown) and a position detector (not shown) that swings each arm (not shown) (not shown). And a welding torch 11 is provided at the tip of the wrist. Further, the robot body 30 receives a position control signal from a robot body control device 70 (to be described later) of the robot control device 40 so that each arm is operated to regenerate the tip of the welding torch 11 based on the teaching data. Yes. Note that the regenerating operation includes touch sensing at a welding start position of a welded joint (not shown) (hereinafter abbreviated as a welded joint), welding of the welded joint, air cutting of the robot main body 30, and the like.
[0011]
The robot control device 40 includes an arithmetic processing device 50, a storage device 60, a robot main body control device 70 that controls the position of each arm of the robot main body 30, an external control device 80 such as the welding power source 10 and the loose cleaning device 20, and the like. It consists of an input device 90 and the like.
[0012]
The arithmetic processing device 50 includes a robot motion arithmetic processing unit 51 that performs motion arithmetic processing on the robot body 30 and an external device arithmetic processing unit 54.
[0013]
The robot motion calculation processing unit 51 includes, for example, a motion calculation processing unit 52 and an abnormality calculation processing unit 53.
[0014]
For example, the motion calculation processing unit 52 instructs each arm of the robot main body 30 via the robot main body control device 70 based on a command from the input device 90 and teaching program data stored in a teaching program storage unit 61 described later of the storage device 60. Arithmetic processing for axis operation or replay operation is performed. In addition, the operation calculation processing unit 52 calculates and processes the operations of the welding power source 10 and the nozzle cleaning device 20 via the external control unit 80 based on teaching program data stored in a teaching program storage unit 61 (to be described later) of the storage device 60. It has become. The above teaching program data includes a retraction program after the occurrence of an abnormality, a nozzle cleaning program from the retraction position, and a backward program to the retraction position.
[0015]
In addition, the motion calculation processing unit 52 performs calculation processing for temporarily stopping the regenerating operation of the robot main body 30 via the robot main body control device 70 in response to a temporary stop command from the abnormality calculation processing unit 53, and the operation of the welded joint in which an abnormality has occurred. It is calculated whether there is weld line data of the weld joint following the weld line data. Then, the motion calculation processing unit 52 receives a command for saving after the occurrence of an abnormality and a saving position stored in a teaching program storage unit 61 (to be described later) of the storage device 60 via the robot body control device 70 in response to a command from the abnormality calculation processing unit 53. The operation for continuing the regenerating operation of the robot main body 30 in the order of the nozzle cleaning program, the reversing program to the retreat position, and the next welded joint operation program is performed. The motion calculation processing unit 52 ends the playback operation of the robot main body 30 via the robot main body control device 70 in response to a playback operation end command from the abnormality calculation processing unit 53.
[0016]
The abnormality calculation processing unit 53 receives various abnormality detection signals from a welding abnormality detection control unit 83, which will be described later, which is the external control device 80, and issues a pause command to temporarily stop the reproduction operation of the robot body 30 as an operation calculation processing unit. 52 is output. Further, the abnormality calculation processing unit 53 determines and calculates whether or not the received various abnormality detection signals match a skip condition stored in a skip condition storage unit 62 described later. In addition, when the result of the determination calculation matches, the abnormality calculation processing unit 53 outputs a confirmation command for confirming the weld line that has been regenerating the temporarily stopped weld joint to the operation calculation processing unit 52, and the welding in which an abnormality has occurred is output. An operation result indicating whether there is a weld line following the line is received. Further, the abnormality calculation processing unit 53 receives the calculation result that there is a continuous weld line, and the operation calculation processing unit 52 stores an after-abnormality saving program stored in a later-described teaching program storage unit 61 of the storage device 60. A command to regenerate the robot body 30 is output in the order of the nozzle cleaning program from the retracted position and the backward program to the retracted position. The abnormality calculation processing unit 53 outputs an instruction to end the reproduction operation to the operation calculation processing unit 52 if the determination calculation result does not match the skip condition and the calculation result has no weld line following the weld line in which the abnormality has occurred. It is like that.
[0017]
The external device external device calculation unit calculation unit 52 externally controls welding-related data in each teaching program data stored in a teaching program storage unit 61 (to be described later) of the storage device 60 in response to a command from the operation calculation processing unit 52. The operation of the welding power source 10 is controlled via a welding power source control unit 81 described later. In addition, the external device arithmetic processing unit 54 transmits nozzle cleaning-related data in each teaching program data stored in a teaching program storage unit 61 (described later) of the storage device 60 according to a command from the operation arithmetic processing unit 52 to the external control 80. The operation of the nozzle cleaning device 20 is controlled via a nozzle cleaning device controller 82 described later.
[0018]
The storage device 60 includes a teaching program storage unit 61 that stores a teaching program and the like, a skip condition storage unit 62, a temporary storage unit 63 for various calculations, and the like.
[0019]
The teaching program storage unit 61 is configured to store teaching program data for each work target workpiece input by the operator using the input device 90. In addition, the teaching program storage unit 61 stores a retraction program after the occurrence of an abnormality, a nozzle cleaning program from the retreat position, and a backward program to the retreat position.
[0020]
The skip condition storage unit 62 teaches the skip condition input by the operator using the input device 90, that is, “under welding”, which is a skip condition when “abnormal welding welding” occurs, and “under welding” when “nozzle contact abnormality” occurs. ”,“ During touch sensing ”, and“ under welding ”when“ arc abnormality ”occurs.
[0021]
The temporary storage unit 63 temporarily stores original data such as various calculations calculated by the operation calculation processing unit 52, the abnormality calculation processing unit 53, and the like.
[0022]
The robot main body control device 70 controls each arm of the robot main body 30 for each axis operation or reproduction operation based on a command from the input device 90 and teaching program data sent from the motion calculation processing unit 52. In addition, the reproduction operation of the robot body 30 is controlled to be paused by a pause command transmitted from the motion calculation processing unit 52, and the reproduction operation of the robot body 30 is continuously controlled by a release command.
[0023]
The external control device 80 includes a welding power source control unit 81, a nozzle cleaning device control unit 82, a welding abnormality detection control unit 83, and the like.
The welding power source control unit 81 controls the welding power source 10 to operate / stop by the operation start / stop command of the welding power source 10 in the teaching program data stored in the teaching program storage unit 61 by the command from the operation calculation processing unit 52. At the same time, the welding current and voltage applied to the welding torch 11 and the wire feed amount are controlled by the welding current and voltage finger data.
[0024]
The nozzle cleaning device control unit 82 operates / stops the nozzle cleaning device 20 according to the operation start / stop command of the nozzle cleaning device 20 in the teaching program data stored in the teaching program storage unit 61 according to the command from the operation calculation processing unit 52. It comes to control.
[0025]
The welding abnormality detection control unit 83 includes a welding scanning abnormality detection control unit 84, a nozzle contact detection control unit 85, an arc abnormality detection control unit 86, and the like.
[0026]
The welding scanning abnormality detection control unit 84 receives a “welding scanning abnormality” signal transmitted from the arc sensor copying control unit (not shown) when it deviates from the arc scanning allowable follow-up range, and receives the “welding scanning abnormality” signal from the abnormality calculation processing unit 53. A signal indicating the occurrence of “copying abnormality” is transmitted. The primary cause of this “welding profile abnormality” is that there is an assembly error in the components of the welded joint so that the weld line of the welded joint taught deviates from the arc tracking allowable tracking range. On the other hand, the other cause of the “welding profile abnormality” is that the shielding performance is impaired by the flow of shielding gas being hindered by the adhesion of spatter or the like that continues to adhere in the torch nozzle of the welding torch 11 during welding. This is because the detected welding current in the scanning control fluctuates and deviates from the arc tracking allowable tracking range. In other words, the abnormality-predicting factor of the welding profiling abnormality is adhesion of a large amount of spatter or the like into the torch nozzle of the welding torch 11.
[0027]
The nozzle contact detection control unit 85 receives a “nozzle contact feed abnormality” signal that senses contact between the workpiece transmitted from the torch nozzle contact detection unit (not shown) and the torch nozzle of the welding torch 11, and receives an error calculation processing unit 53. The generation signal of “nozzle contact abnormality” is transmitted. The original cause of this “nozzle contact abnormality” is that the torch nozzle of the welding torch 11 contacts the work during the regenerating operation except during teaching and sensing such as touch sensing. On the other hand, another cause of the “nozzle contact abnormality” is that welding is performed by sputtering or the like in which a voltage is applied from the torch nozzle contact detection power source to the torch nozzle and workpiece of the welding torch 11 and continues to adhere to the inside of the torch nozzle of the welding torch 11 during welding. When the torch nozzle of the torch 11 and a chip (not shown) (not shown) are conducted, the difference between the applied voltage and the arc voltage is reduced, and the torch nozzle contact detection unit (not shown) is in contact with the workpiece. It is in the false detection that it did.
[0028]
Another cause is that a voltage is applied from a sensing power source that also serves as the welding power source 10 to the welding torch 11 and the workpiece, and the welding torch is caused by spattering that continues to adhere to the inside of the torch nozzle of the welding torch 11 during touch sensing. When the eleven torch nozzles are connected to the chip, the sensing voltage becomes low, and the torch nozzle contact detection unit (not shown) may erroneously detect that the torch nozzle is in contact with the workpiece. That is, both abnormal assumption factors of “nozzle contact abnormality” are adhesion of a large amount of spatter and the like into the torch nozzle of the welding torch 11.
[0029]
If the welding current detection signal (WCR) transmitted from the welding power source 10 during welding is not received within the arc abnormality setting time during welding, the arc abnormality detection control unit 86 detects “arc abnormality”, and the abnormality calculation processing unit 53 indicates “ An “abnormal arc” occurrence signal is transmitted. The original cause of this “arc abnormality” is that an arc break occurs due to some factor during welding. On the other hand, the other cause of the “arc abnormality” is that the shield gas flow is obstructed by the adhesion of the spatter or the like that continues to adhere in the torch nozzle of the welding torch 11 during welding, and the shielding performance is impaired. Thus, the detected welding current detected by the welding power source 10 for feedback control fluctuates and the WCR signal from the welding power source 10 cannot be received. That is, the cause of the abnormality of “arc abnormality” is adhesion of a large amount of spatter or the like into the torch nozzle of the welding torch 11.
[0030]
The input device 90 is, for example, a teaching pendant. With this input device 90, the operator can input the motion of each axis of each arm of the robot body 30 and teach the teaching operation of each workpiece. In addition, the operator can skip conditions such as “Welding improper”, which is a skip condition when “Welding”, “Nozzle contact error” occurs, “Welding”, “Touch sensing” and “Arc error” "When welding" is entered and set. In addition, teaching operations are performed for a retraction program after the occurrence of an abnormality, a nozzle cleaning program from the retraction position, and a backward program to the retraction position.
[0031]
Next, an operation method using the welding robot apparatus having such a configuration will be described.
[0032]
In order to operate this welding robot apparatus, as shown in FIG. 3, an abnormality to be skipped among abnormalities ("arc abnormality", "nozzle contact abnormality", etc.) is set in advance by an operator (S2). When a workpiece made of a welded joint is set at a predetermined position, a teaching program including touch sensing is set for the welding start position of each welded joint that reproduces the workpiece (S3). Subsequently, when the start of the welding operation is started by the operator, the waiting robot main body 30 performs touch sensing at the welding start position of the first welded joint according to the teaching program to sense an appropriate welding start position, and then sequentially performs other operations. In the same manner, the weld joint is touch-sensed (S4).
[0033]
When “nozzle contact abnormality” is output from the nozzle contact detection control unit 85 of the external control unit 80 during touch sensing of the third weld joint (S5), the “nozzle contact abnormality” signal is calculated as an abnormality calculation. The robot main body 30 is temporarily stopped by a temporary stop command from the operation arithmetic processing unit 52 and input to the processing unit 53, and the welding power source 10 is stopped via the welding power source control unit 81 of the external control device 80 to perform touch sensing. Is interrupted (S6).
[0034]
In addition, when “arc abnormality” is output from the arc abnormality detection control unit 86 of the external control unit 80 during welding of the third weld joint, this “arc abnormality” signal is input to the abnormality calculation processing unit 53. Thereafter, the same processing as the “nozzle contact abnormality” is performed. The subsequent processing will be described as “arc abnormality” processing.
[0035]
Then, it is determined by the abnormality calculation processing unit 53 whether or not “arc abnormality” matches the skip condition (S7). If “arc abnormality” matches the skip condition as a result of the determination, the operation calculation processing unit 52 performs the teaching program. It is determined from the data whether there is a fourth welded joint followed by the third welded joint (S8), and the robot is created by a retracted teaching program from the teaching program storage unit 61 of the storage device 60 that is created and stored in advance. The main body 30 is retracted (S9).
[0036]
The robot body 30 is operated from the retracted position, and the welding torch 11 is positioned at a nozzle cleaning position (not shown) of the nozzle cleaning device 20 by a nozzle cleaning program from the teaching program storage unit 61, and in response to a command from the nozzle cleaning device control unit 82. Nozzle cleaning is performed to remove spatter and the like adhering in the torch nozzle of the welding torch 11 by operating the nozzle cleaning device 20 (S10), and the robot body 30 is retracted by a backward program from the teaching program storage unit 61 of the storage device 60. Move to position.
[0037]
Again, the other welded joints are sequentially touch-sensing from the fourth welded joint of the same teaching program according to the command from the operation calculation processing unit 52 and are welded (S11). At this time, touch sensing is performed in a state where spatter and the like are removed in the torch nozzle of the welding torch 11 and welding is performed, so that it is possible to prevent the occurrence of “arc abnormality” due to spatter adhesion or the like at the weld joint thereafter. it can. Further, when the “abnormal welding profile” occurs, the subsequent “abnormal welding profile” due to adhesion of spatter or the like at the weld joint can be prevented.
[0038]
Furthermore, when a nozzle contact abnormality occurs, it is possible to prevent the occurrence of “nozzle contact abnormality” due to adhesion of spatter and the like at the welding start position of the welded joint, and the above “arc abnormality” and “welding” described above. In the case of `` copying abnormality '', the existing welded part becomes a defective welded part, and it takes time to go to work such as gouging on the defective welded part in the subsequent repair work, whereas when `` nozzle contact abnormality '' occurs Since there are no defective welds, repair work can be facilitated.
[0039]
Then, welding of all the welded joints is completed (S12), the welded workpiece is removed from the predetermined position, and the next workpiece is set. And the workpiece | work which the welding operation was completed is sent to the following repair work process, and only the 3rd welded joint with an unwelded part is repaired, and reduction of repair work can be aimed at.
[0040]
In the above-described embodiment, the nozzle cleaning device 20 performs a cleaning operation on the torch nozzle of the welding torch 11 positioned in a cleaning state (not shown). However, the used torch nozzle or tip is detached from the welding torch 11 and is new or cleaned. A nozzle cleaning device that replaces the torch nozzle or the tip may be used. With such a nozzle cleaning device, there is no spatter adhesion on the torch nozzle and the welding tip, and it is possible to minimize the occurrence of abnormalities due to spatter adhesion in subsequent welding.
[0041]
Further, in the above-described embodiment, the operator teaches the teaching program data and skip conditions of each workpiece by the input device 90, but instead of this input device 90, an offline using a personal computer such as a computer separately. A form using a teaching device may be used.
[0042]
【The invention's effect】
As described above, the invention of claim 1, by generating an arc between the wire and the weld joint fed from the welding torch, sequentially performs welding of the weld joint in a workpiece comprising a plurality of welded joint welding In the automatic operation method of the robot apparatus, during the regenerating operation of the welding robot, the regenerating operation is interrupted when any of the abnormalities of welding tracing abnormality, nozzle contact abnormality, arc abnormality indicating the disappearance of the arc occurs, wherein any of the abnormalities, welding copying abnormality occurs during welding, the nozzle occurred or during touch sensing in the weld contact abnormal, or if the arc is abnormal that occur during welding, generation of the any of the abnormal It determines the presence of the welded joint following the point, if it is determined that the there are any subsequent abnormality occurrence position data welded joint, retracted from the generation position of the one of the abnormality, the soluble Removed or conducted exchange of nozzles of the welding torch of deposits adhering to the nozzle of the torch, in which the subsequent one of abnormality playback operation for the next welded joint of the welded joint that occurs, the welding abnormality By performing welding on the next welded joint that has been skipped after eliminating the assumed cause after occurrence, it is possible to prevent the recurrence of welding abnormalities and to provide an automatic operation method for a welding robot apparatus that reduces repair work.
[Brief description of the drawings]
FIG. 1 is a control block diagram of a welding robot apparatus according to the present invention.
FIG. 2 is a flowchart for explaining an automatic operation method of the welding robot apparatus.
FIG. 3 is a flowchart for explaining a conventional laser processing resuming method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Welding power supply 11 Welding torch 20 Nozzle cleaning apparatus 30 Robot main body 52 Operation | movement calculation process part 53 Abnormality calculation process part 62 Skip condition memory | storage part 83 Welding scanning abnormality detection control part 85 Nozzle contact detection control part 86 Arc abnormality detection control part S5 Abnormality generation | occurrence | production S6 Regeneration operation interruption S7 Predetermined abnormality determination S8 Continuous weld joint determination S9 Retraction S11 Next weld joint regeneration operation

Claims (1)

By generating an arc between the wire and the weld joint fed from the welding torch, the automatic driving method of welding robot system sequentially performing the welding of the weld joint in a workpiece comprising a plurality of welded joints,
During the regenerating operation of the welding robot, the regenerating operation is interrupted when any one of the welding abnormality, the nozzle contact abnormality, and the arc abnormality indicating the disappearance of the arc occurs,
Wherein any of the abnormalities, welding copying abnormality occurs during welding, the nozzle occurred or during touch sensing in the weld contact abnormal, or if the arc is abnormal that occur during welding, generation of the any of the abnormal Determine the presence or absence of a welded joint following the location,
When it is determined that there is a welded joint that follows any one of the occurrences of the abnormality, the deposit is removed from the position of the occurrence of any abnormality , and the deposit adhered to the nozzle of the welding torch or the welding torch An automatic operation method for a welding robot apparatus , wherein nozzle replacement is performed, and a welding joint next to the welding joint in which any one of the abnormalities occurs is regenerated.

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