KR101474853B1

KR101474853B1 - Management system for dressing of welding tip

Info

Publication number: KR101474853B1
Application number: KR20140005070A
Authority: KR
Inventors: 이열성
Original assignee: 한국 오바라 주식회사
Priority date: 2014-01-15
Filing date: 2014-01-15
Publication date: 2014-12-19

Abstract

It is an object of the present invention to provide a system capable of collectively performing maintenance, particularly dressing quality control, throughout the entire process accompanied with automation of a welding process in a welding robot, And a dressing checker for checking the quality to generate a good or bad check signal. The dressing checker communicates with the individual dressing checkers under the DeviceNet communication environment to receive the check signal from the dressing checker to preserve dressing quality data, A PLC for receiving and executing a program for controlling a dressing checker and a welding robot in accordance with a work command from a terminal in a communication environment; and a user interface provided as a terminal for operating a welding tip of a plurality of welding robots When the pressing force value in the individual dressing process is input A possible input window, a dressing history for the welding tips of the individual welding robots, and the results of the checks sent out from the respective dressing checkers, and the number of dressings for the welding tips of the individual welding robots reaches a predetermined set value And a touch screen for displaying a warning signal for the welding tip of the welding robot when a bad signal from the dressing checker is confirmed even after the welding signal is detected.

Description

TECHNICAL FIELD [0001] The present invention relates to a welding tip dressing management system,

The present invention relates to a welding tip dressing management system, and more particularly, to a welding tip dressing management system for managing a dressing quality capable of collectively managing the individual quality of a dressing for a welding tip that is a consumable material detachably mounted on a plurality of spot welders arranged in a welding line &Lt; / RTI >

In an electric resistance spot welding line for welding a white body or the like of an automobile, a pair of welding tips mounted on a welding gun are simultaneously pressed and energized with a work interposed therebetween and welded by electric resistance heat emitted by the work.

The welding tip used for the electric resistance spot welding is deformed and worn out by repeating welding, and the welded material is welded to the surface, so that good welding can not be continued. When the electrode tip is heated by the continuous operation of spot welding and oxidation progresses and the contact resistance is increased, picking up of the plated product occurs particularly in the welding of the aluminum alloy or the plated steel plate. Therefore, when the number of RB points reaches a predetermined value or more, the tip of the electrode is heated by the continuous operation of the surface spot welding of the welding tip, and the oxidation progresses to increase the contact resistance. In particular, in the welding of aluminum alloy or plated steel sheet, A pickup of water occurs.

In addition, even if the welding current is kept constant, if the area of the tip increases, the current density decreases to cause welding failure. Therefore, the tip of the welding tip is dressed regularly during continuous welding, It is necessary.

In this way, returning the tip shape of the welding tip to its initial shape is referred to as dressing, thereby eliminating contamination at the tip of the welding tip. Although the dressing of such a welding tip has been performed by machining using a lathe in the past, an automated tip dressing apparatus is used because polishing with a lathe requires skill and time. The tip dressing apparatus has a rotary blade that rotates by gear driving and drives the robot welding gun to rotate the rotary blade in a state in which the pair of welding tips are pressed up and down so that the pair of welding tips are simultaneously cut .

The welding tip thus dressed is moved to a dressing inspecting machine, and the welding tip is brought into close contact with the concave inspection groove formed in the dressing inspecting machine. Then, the welding tip is radially formed around the inspection groove, and an elongated concave channel The quality of the dressing is checked through a dressing checker for checking the quality of the dressing of the welding tip by measuring the degree of escape of the air pressure applied through the groove between the welding tip and the inspection groove which are in close contact with each other, Which can no longer be expected to recover the quality of the weld through the dressing, is automatically replaced with a new welding tip via a dressing welding tip exchanger. In addition to using air pressure, the dressing checker is increasingly used as dressing to judge whether the dressing is good or bad according to the proximity of the initial shape through the optical sensor.

15 is a flowchart for explaining an example of the transmission / reception relationship between the controller and the TDC of the welding robot at the time of the tip dressing operation, and the above-described dressing procedure is described with a specific example.

However, in the welding process line composed of the conventional welding robots, such dressing inspection has been individually performed for each welding robot. However, as the welding automation ratio by the welding robot is almost 100%, the individual dressing quality check for a large number of welding robots There has been a demand for a system for collectively managing such information.

An object of the present invention is to provide a system capable of collectively performing maintenance, particularly dressing quality control, throughout the entire process in connection with automation of a welding process to a welding robot.

According to an aspect of the present invention, there is provided a welding tip dressing management system comprising: a plurality of welding robots aligned on a welding line; an X- or C-shaped welding gun mounted on the welding robot; A dressing device which is separately disposed around each welding robot and restores the outer shape of the tip portion of the worn welding tip worn by the welding operation to the initial shape by cutting; 1. A welding tip dressing management system having a dressing checker that verifies the dressing quality of a plurality of welded tips by the device and generates a good or bad check signal, the system comprising: a device in communication with each of the dressing checkers in a DeviceNet communication environment, And stores the dressing quality data. In the Ethernet communication environment, A programmable logic controller (PLC) for receiving and executing a program for controlling the dressing checker and the welding robot according to a work command from the end of the welding operation; and a user interface A dressing history for the welding tips of the individual welding robots and the results of the inspection sent from the respective dressing inspectors are displayed on the welding tips of the individual welding robots, And a touch screen type terminal for displaying a warning signal for the welding tip of the welding robot when a bad signal from the dressing checker is confirmed even after the number of times of dressing reaches a predetermined set value, And the welding tip is brought into close contact with the inspection groove, And the pressure is judged to be good or bad depending on the degree of leakage.

In addition, the welding tip dressing management system of the present invention is characterized in that a plurality of welding robots having a process relation is organized into one group, and a dressing check result of a plurality of groups is stored in a group And are collectively displayed.

The welding tip dressing management system of the present invention collects only the history of the warning signals stored in the PLC by a touch operation of the operator through the user interface of the touch screen and collectively displays the history of the warning signals, Occurrence time, and place of occurrence.

According to the welding tip dressing management system to which the present invention is applied, quality control of the dressing managed for each welding robot is unified.

Specifically, only the alarm details generated by the defects identified through the TDC are displayed collectively. As shown in the figure, the date, time, and place of the alarm occurrence can be visually confirmed. If defects are concentrated at a specific position It is necessary to correct the various factors such as whether the welding is performed on the specific material of the material to be welded, whether only the welding tip of a specific standard is defective, or whether it is caused by a special welding environment, and then corrects the number of times of dressing or the pressing force input value , It is possible to reduce the defective dressing by carrying out a countermeasure to use a welding tip of a different standard, and exert an excellent effect in minimizing defects in a series of welding processes.

1 is a perspective view showing an example of a welding automation line.
FIG. 2 illustrates an example of a system to which the present invention is preferably applied, and shows an example of organization of components by communication environment.
FIG. 3 shows an example of a main screen of a touch screen of a system to which the present invention is preferably applied.
FIG. 4 is an interface screen that is displayed when a 'TDC status display screen' button of FIG. 3 is touched and displays a dressing operation and a dressing result for each individual welding robot.
5 is an interface screen showing that a virtual keyboard appears while entering the editing mode by touching the individual 'pressure reference value' in FIG.
FIG. 6 is an interface screen requesting confirmation when the individual 'Reset' of FIG. 4 is touched and a reset window 61 appears at the center.
FIG. 7 is an interface screen for confirming whether an alert window is displayed when an individual 'Reset' button of 'NG counter initialization' of FIG. 4 is touched by an erroneous operation and whether or not the 'OK' button of the 'complete COUNT' column is clicked.
FIG. 8 shows an example of a display of 'Bypass' with visibility when touching the individual 'Bypass' button in the 'TDC BYPASS' column of FIG. 4, and an example of 'Bypass' Screen.
FIG. 9 is a screen displayed when a 'alarm occurrence history' button of FIG. 2 is touched, and is a screen for displaying a date and time of an alarm generated by a defect identified through TDC, a message, and a record of an alarm reset time.
FIG. 10 is an interface screen that is displayed when a user touches the 'action details' button of FIG. 4, and can classify and code and record the action patterns from A to H. FIG.
FIG. 11 is a screen that is displayed when a 'robot number' button of FIG. 4 is touched. In FIG. 11, the pressure reference value and the actual measurement value set for each robot are displayed in a graph form.
FIG. 12 is a data management interface screen that appears when the left and right upper corner portions of the screen of FIG. 3 are touched simultaneously.
FIG. 13 is an alarm information file management screen displayed in the order of "data management" tab ->"alarminformation" tab in FIG.
FIG. 14 shows a logging information file management screen displayed in the order of 'Data Management' tab ->'LoggingInformation' tab in FIG. 12.
15 is a flowchart for explaining the transmission / reception relationship between the controller of the welding robot and the TDC during the tip dressing operation.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a view showing a state in which a plurality of welding robots 1 are arranged in a welding automation line, and a welding tip exchanging apparatus 2, a welding tip dressing apparatus and a dressing checker 3 are arranged around each welding robot 1 .

A welding tip which can be detached is mounted on the opposite electrode of the welding gun of X type or C type mounted on the welding robot 1. A welding tip which reaches a predetermined welding spot set within a range of 30 to 100 degrees, (Not shown) of the dressing inspecting machine 3 after the dressing has been performed in the apparatus, and then the air pressure applied through the concave channel groove formed radially around the inspection groove is welded to each other by welding The welding tip is worn so that the quality of the dressing of the welding tip is measured by measuring the degree of leakage through the tip between the tip and the inspection groove and the recovery of the welding quality through the dressing is no longer possible by the predetermined number of dressings. Is exchanged with a new welding tip automatically via the exchanging device (2).

2 shows an example of a system to which the present invention is preferably applied. In the DeviceNet communication environment, each of a plurality of dressing checkers 3 is connected to a PLC (programmable logic controller) 5 through an I / O block 4, And the PLC 5 is connected to the touch screen 6 through a switching hub in an Ethernet communication environment to display a dressing quality and enable field setting, And is connected to the user console 7. Also, the PLC 5 is connected to the upper PLC 8 through the switching hub and is subordinate to an upper system so that data storage and work instructions are performed.

FIG. 3 shows an example of a main screen of the touch screen 6. When a 'cell layout screen' button 31 is touched, a plurality of welding robots on a cell-by-cell line as well as a welding tip attaching / And the display state of the arrangement state of the dressing device group, and the layout is confirmed and corrected based on the switching.

On the other hand, when the 'TDC (tip dressing checker) status display screen' button 33 is touched in FIG. 3, the dressing situation of the welding tip of the individual welding robot assigned to each of the plurality of process groups is displayed in real time When the 'previous process TDC display screen' button of the numeral 32 is touched, the individual groups displayed through the 'TDC status display screen (33)' button of each process group are reduced When the 'alarm occurrence history' button of the reference numeral 34 is touched, the process is switched to the screen displaying all the groups at once and the process is performed through the 'full process TDC display screen 32' and the 'TDC status display screen 33' Only the process defects that are displayed together are switched to a screen that is displayed separately.

FIG. 4 shows a screen for displaying the defect occurrence status of the robot and the TDC by touching the button of the TDC status display screen 33 shown in FIG. 3, and first of all, touches the ' , The process moves to the main screen of Fig. Reference numeral 332 denotes a process display window for displaying the process name of the current process group indicated below. The process names displayed on the process display window 332 and one of the process buttons 333 selected on the right side in FIG. 4 are changed to bright colors. In other words, the process button 333 is selected The display content of the process display window 332 is changed.

The 'pressure reference value' 334 is a window for inputting the electrode pressing force reference value in each TDC. In this drawing, the individual pressure reference values of 'R01' to 'R12', which are serial numbers respectively assigned to the robots belonging to the process group, When the user touches the individual boxes displayed in pink at the time of inputting, as shown in FIG. 5, the individual chambers enter the edit mode, and at the same time, the virtual keyboard 3341 appears and the pressure reference values can be separately set. The electrode pressing force, to indicate the force being in close contact with the inspection stage of the group dressing check when after the dressing process the ends of the welding tips check whether the dressing in a predetermined radius of curvature, for example, using air pressure is 5kg / cm ² 250 when If the dressing checker is below the lower limit of the above range, the dressing checker will emit a bad signal more than necessary. If the dressing checker is larger than the upper limit of the above range, the dressing checker will not emit an appropriate bad signal. It may fall or be damaged due to excessive load applied to the dressing checker. In the 'final pressure value' field of reference numeral 342, the most recently measured pressure value is displayed so that it can be referred to when the pressure reference value 334 is modified.

The number of times of TDC NG occurrence of reference numeral 335 is divided into NG # 1 to NG # 3. For example, dressing is performed after welding is performed a predetermined number of times within a range of 30 to 100 shots from the beginning, 1, a check result is sent from the corresponding dressing checker to the PLC under the DeviceNet communication environment, and the result of the inspection is transmitted from the PLC in the Ethernet communication environment NG # 1 'of the welding robot corresponding to the number of times of TDC NG occurrence 335 of the screen. When there is no abnormality,' 0 'is displayed. If there is an abnormality,' 1 'is displayed. At this time, the welding robot re-dresses the welding tip and checks the dressing checker. If there is no abnormality, the welding robot returns to the process line and '2' is displayed in the NG # 1.

However, if an abnormality is confirmed again in the dressing checker after the second dressing, a 'TDC status display screen' at the top of FIG. 4 is displayed, for example, 'Group 1 Robot 1 Fault' on a red background , A warning is issued. At this time, the field operator confirms the welding tip mounted on the welding robot, checks the state of attachment of the welding tip and the appearance after dressing, measures the fault, and then presses an individual 'confirmation completed' 'NG # 1' is displayed as '3', and 'CHECK number' of the reference numeral 336 is displayed as '3' as the sum of NG # 1 to NG # 3.

In addition, an individual 'Reset' button of 'NG counter initialization' 338 in FIG. 4 is reset when a new welding tip is exchanged through inspection of the appearance of the welding tip or if it is defective due to an error of the dressing checker If the 'Reset' is touched, a reset window 61 is displayed as shown in the center of FIG. 6 to request confirmation. If the user touches 'YES' in the reset window, the number of TDC NG occurrences 335 'NG # 1' to 'NG # 3' and the number of times of checking 336 are set to '0'.

7, in order to prevent the field operator from resetting due to a mistake during the operation of the touch screen in connection with the individual reset button of the " NG counter initialization " As shown in the figure, there is also provided a safety device for displaying an alarm window 71, in which a reset is not performed unless a confirmation completion button 337 of the 'complete COUNT' column is clicked.

On the other hand, the individual 'Bypass' button of the 'TDC BYPASS' column 339 of FIG. 4 indicates that the welding process needs to be operated at a relatively low TDC relative to other parts, or due to a failure of a specific dressing checker, In order to prevent erroneous operations such as when TDC is manually executed in the short term, it is a button to be operated when the TDC check is not passed when it is difficult to apply uniformly. In this case, as shown in Fig. 8, 339) button in bright color and at the same time, the 'present BYPASS' of the brightly colored background is displayed in the 'TDC status' column of the reference numeral 340.

When a button allocated to each welding robot is touched in the "action details" column 341 of FIG. 4, a pop-up screen of FIG. 10 appears. The code A changes the pressure reference value of the air pressure and re- And the code B is an interface screen in which an action pattern from A to H is determined in advance, such as indicating a processing pattern for re-dressing without changing the pressure reference value of the air pressure, and can be coded and recorded. It is not limited to eight patterns in the screen of Fig. 10, but the number of patterns can be increased or decreased, and the contents of the action patterns can be arbitrarily changed in accordance with the work environment.

On the other hand, in the leftmost 'robot number' column in FIG. 4, for example, R01 to R12 are displayed. When these individual buttons are touched, the accumulated pressure value and actual measured value set for each robot in FIG. Quot; Save " at the bottom right of FIG. 11 is stored in an internal storage medium such as a CF card provided in the TDC so as to store the accumulated pressure value of the individual robot and the actual measured value in the storage medium , It can be moved from the internal storage medium to the external storage medium. The stored data is used as analysis data for fine tuning of the individual welding robots.

As described above, the state of each of the plurality of robots in the individual process group is displayed at a glance on the TDC status display screen shown in Fig. 4, as described with reference to Figs. 5 to 8, The pressing force reference value is corrected, the abnormality of the dressing is displayed, and all the operations of recording or resetting these histories can be performed.

FIG. 9 is a screen that appears when the 'alarm occurrence details' button 34 of FIG. 2 is touched. Only the alarm details generated by the defects identified through the TDC as described above are displayed collectively. , The date and time of the alarm occurrence, the time and place can be visually confirmed. If the defects are concentrated at a specific position, it is determined whether the welding is caused by the specific material of the welded material, Etc., it is possible to reduce the defective dressing by correcting the number of dressings, correcting the pressing force input value of the dressing checker, or using countermeasures of using welding tips of different specifications, And exerts an excellent effect in reducing the defects in the process as much as possible.

In addition, when 'Cursor On' of 3401 in FIG. 9 is touched, the screen is released from the locked state, and the cursor is moved to a line to enable editing of the corresponding line. When 'Cursor Off' Return to the locked state and release the edit state. 'Up' or 'Down' of the reference numeral 3403 is a button for executing the up-down of the cursor, and 'Delete' of the reference numeral 3404 is a button for deleting the corresponding row activated by the cursor. Delete All 'is a button for deleting all lines, and' Save '3406 is a button for temporarily storing an alarm history in an internal storage medium provided in the TDC, for example, a CF card.

FIG. 12 is a data management interface screen displayed when the left and right upper corner portions of the screen of FIG. 3 are touched simultaneously. When the 'Data Management' tab on the upper right side is clicked, Alarm information 'window shown in FIG. 13 is displayed and an operation of transferring the file of the alarm information from the internal storage medium to the external storage medium becomes possible by clicking on the' Alarm Information 'tab. First, the part of' 3521 ' (Indicated by Alarmhst *. Csv in Fig. 13) stored in the internal storage medium displayed on the internal storage medium, and then click the " copy " button of the reference numeral 3522. Then, For example, a USB memory) is touched and designated, the data of the internal storage medium is copied to the external storage medium. The lower part of FIG. 13 shows the csv file opened through Microsoft Excel. In the part 3524, the alarm occurrence date and time and the alarm contents in the individual robot process are displayed for each pattern. The completion time and the time at which the NG counter is initialized are displayed.

On the other hand, FIG. 14 is a logging information data management screen displayed when the third 'Logging Information' tab among the buttons arranged in the longitudinal direction from the upper part of the screen is clicked on the 'Data Management' tab of FIG. 12, 13, when the csv file copied to the external storage medium is opened through Excel, a record of the TDC logging time is displayed in the left column, and a pressure value measured in the TDC is displayed in the right column. The csv file format allows archives to be processed in a variety of graphical forms.

1: Welding robot
2: Welding tip exchanger
3: Welding tip dressing device and dressing checker
31: Cell layout screen
32: Full process TDC display screen
33: TDC status display screen
331: Selection screen view 332: Process display window
333: process button 334: pressure reference value
3341: Virtual keyboard
335: Number of TDC NG occurrences 336: Number of checks
337: OK
339: Bypass 340: TDC state
34: Alarm occurrence history

Claims

A welding robot comprising: a plurality of welding robots arranged on a welding line; an X-type or C-type welding gun mounted on the welding robot; a welding tip detachably mounted on each of opposing electrodes of the welding gun; A dressing device which is arranged in the dressing device and restores the outer shape of the tip end portion of the welded tip worn by the welding operation to the initial shape by cutting and a dressing device which confirms the dressing quality of the plurality of welding tips by the dressing device, And a dressing checker for generating a dressing checker, wherein the dressing checker communicates with each of the dressing checkers under a device net communication environment to receive a check signal from the dressing checker to preserve dressing quality data, Which controls the dressing checker and the welding robot according to the work command A programmable logic controller (PLC) for receiving and executing the RAM, and an input window having a user interface and capable of inputting a pressing force value in an individual dressing process for a welding tip of a plurality of welding robots by a touch operation of an operator , The dressing history of the welding tips of the individual welding robots and the inspection results emitted from the individual dressing inspectors are displayed and even after the number of dressing times of the welding tips of the individual welding robots reaches a predetermined set value, And a touch screen type terminal for displaying a warning signal for a welding tip of the welding robot when a bad signal from the welding robot is confirmed,
Wherein the dressing checker comprises a concave inspection groove, and the welding tip is brought into close contact with the inspection groove, and air pressure is applied to judge whether the dressing is good or bad according to the degree of leakage.

The welding robot according to claim 1, wherein a plurality of welding robots having process relations are organized into one group, and a dressing check result of a plurality of groups is divided into groups by a touch operation of an operator through the user interface of the touch screen Wherein the display means displays a batch of the welding tip dressing management system.

3. The method according to claim 2, wherein only the history of the warning signals stored in the PLC is displayed collectively by a touch operation of the operator through the user interface of the touch screen, and the date, Wherein the welding tip dressing management system comprises: