Welding management device for managing welding conditions of spot welding

Abstract

The welding management device manages welding conditions of spot welding. The welding management device has a control device and an arithmetic processing device. The arithmetic processing device includes a storage unit that stores main data of a welding condition in which an item value included in the welding condition is configured from a reference value. The control device includes a history information generation unit that creates change history information including a pre-change item value and a post-change item value when the item value of the welding condition is changed. The storage unit stores the change history information generated by the history information generation unit together with reference data.

Description

Technical Field

[0001] The present invention relates to a welding management device for managing welding conditions of spot welding. Background Art

[0002] In the past, as a welding device for fixing parts to each other, an arc welding device having a welding torch for welding by arc discharge is known (for example, Japanese Patent Publication No. 2016-124076 and Japanese Patent Publication No. 2006-26655). In addition, a spot welding device having a spot welding gun for welding by energizing electrodes to each other is known (for example, Japanese Patent Publication No. 5-220580). In addition, a robot device is known in which a work tool for welding is mounted on a robot and welding is performed while changing the position and posture.

[0003] In spot welding, a pair of electrodes are used to clamp a workpiece and apply pressure. When current is passed through the electrodes, heat is generated due to resistance. Then, the workpiece melts at the point where the electrodes contact, and welding is performed. In spot welding, the conditions for passing current through the electrodes are predetermined as welding conditions. The pattern of the current flow, such as the current value and the energization time, is determined in the welding conditions.

[0004] For example, welding conditions are determined according to the welding points of the workpieces to be spot welded. The welding conditions depend on the thickness, shape, and material of the workpieces to be spot welded. Therefore, it is difficult for the operator to determine the optimal welding conditions at once. The operator can determine the optimal welding conditions while changing the welding conditions.

[0005] For example, in order to determine the best welding conditions, the operator may gradually change some items of the welding conditions while performing welding. Alternatively, the operator may change the values ​​of some items of the welding conditions to determine the welding quality after welding. The welding conditions are stored in, for example, a welding timer that supplies current to the electrode of a spot welding gun.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2016-124076

[0009] Patent Document 2: Japanese Patent Application Publication No. 2006-26655

[0010] Patent Document 3: Japanese Patent Application Laid-Open No. 5-220580 Summary of the invention

[0011] Problems to be solved by the invention

[0012] In the prior art, when the values ​​of some items of welding conditions are changed, the item values ​​of the welding conditions before the change are not saved. Therefore, the past management of welding conditions is not substantially performed. Alternatively, welding conditions including all item values ​​are stored in a device other than the welding timer. For example, each time a welding condition is changed, the welding condition is stored with a date and a number. Therefore, when an operator investigates past welding conditions, it is necessary to compare each welding condition to find the changed items and the changed values. Thus, there is a problem that it takes effort to manage welding conditions. In order to manage welding conditions, it is preferable to be able to easily obtain the changed items and the changed values ​​of welding conditions.

[0013] Means for solving problems

[0014] One aspect of the present disclosure is a welding management device for managing welding conditions of spot welding. The welding management device includes a storage unit that stores reference data of welding conditions, wherein the values ​​of items included in the welding conditions in the reference data are composed of reference values. The welding management device includes a history information generation unit that, when the values ​​of one or more items of the welding conditions are changed, creates change history information including the values ​​before and after the change of the one or more items. The storage unit stores the change history information generated by the history information generation unit together with the reference data.

[0015] Effects of the Invention

[0016] According to the aspect of the present disclosure, it is possible to provide a welding management device that can easily manage welding conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a perspective view of a robot system including a robot device and a calculation processing device in the embodiment.

[0018] Figure 2 It is the block diagram of the robot system.

[0019] Figure 3 This is an explanatory diagram when creating master data of welding conditions in the embodiment.

[0020] Figure 4 This is an explanatory diagram when creating the change history information of the welding conditions in the embodiment.

[0021] Figure 5 This is a diagram for explaining the updating of welding conditions stored in the welding timer.

[0022] Figure 6 This is the first diagram for explaining restoration of welding conditions at an arbitrary point in time in the past.

[0023] Figure 7This is a second diagram for explaining restoration of welding conditions at an arbitrary point in time in the past.

[0024] Figure 8 This is a diagram for explaining restoration of some items of welding conditions at an arbitrary time point in the past.

[0025] Fig. 9 is a block diagram of another robot system in the embodiment. DETAILED DESCRIPTION

[0026] Reference Figures 1 to 9 , a welding management device in an embodiment is described. The welding management device in this embodiment manages welding conditions of spot welding. In this embodiment, a robot device having a spot welding gun is used as an example for description as a welding device.

[0027] Figure 1 It is a perspective view of the robot system in this embodiment. Figure 2 is a block diagram of the robot system in this embodiment. Figure 1 and Figure 2 The robot system includes a robot device 9 and a processing unit 7 connected to a control unit 2 of the robot device 9. The robot device 9 can perform welding at a desired welding point 94 while changing the position and posture of the welding gun 5. The robot device 9 includes: a welding gun 5 as a welding work tool, a robot 1 that changes the position and posture of the welding gun 5, and a welding timer 6 that supplies welding current to an electrode 23 of the welding gun. The robot device 9 includes a control unit 2 that controls the actions of the robot 1 and the welding gun 5.

[0028] The workpieces 91 and 92 of this embodiment are plate-like members. The workpiece 92 has the same planar shape as the workpiece 91. The workpieces 91 and 92 are fixed to a stand 93 by a device not shown. The robot device 9 performs spot welding at a plurality of welding points 94. By performing spot welding, the workpieces 91 and 92 are fixed to each other.

[0029] The robot 1 of the present embodiment is a multi-joint robot including a plurality of joints. The robot 1 includes an upper arm 11 and a lower arm 12. The lower arm 12 is supported on a rotary base 13 in a rotatable manner. The rotary base 13 is supported on a base 14 in a rotatable manner. The robot 1 includes a wrist 15 connected to the end of the upper arm 11. The wrist 15 includes a flange 16 for fixing the welding gun 5. The robot 1 of the present embodiment has 6 drive axes, but is not limited to this mode. The robot can adopt any robot that can move a working tool.

[0030] The robot 1 of this embodiment includes a robot driving device 21 for driving components such as the upper arm 11. The robot driving device 21 includes a plurality of driving motors for driving the upper arm 11, the lower arm 12, the rotating base 13, the wrist 15, and the flange 16. The welding gun 5 includes a tool driving device 22 for driving the welding gun 5. The welding gun 5 includes electrodes 23 facing each other. In this embodiment, one electrode 23 is a fixed electrode and the other electrode 23 is a movable electrode. The tool driving device 22 of this embodiment includes a motor for driving the movable electrode relative to the fixed electrode.

[0031] The robot 1 includes a state detector for detecting the position and posture of the robot 1. The state detector in this embodiment includes a rotation position detector 24, which is installed in the drive motor of each drive shaft of the robot drive device 21. The rotation position detector 24 is composed of an encoder, for example. Based on the output of the rotation position detector 24, the position and posture of the robot 1 are detected.

[0032] The control device 2 has a control device body 4 having a processing device (computer) having a CPU (Central Processing Unit) as a processor. The processing device has a RAM (Random Access Memory) and a ROM (Read Only Memory) connected to the CPU via a bus. The control device 2 drives the robot 1 and the welding gun 5 according to a pre-made action program 41. The robot device 9 of this embodiment automatically performs spot welding on the workpieces 91 and 92 at the welding point 94.

[0033] The operation processing device of the control device body 4 includes a storage unit 42 that stores information related to the control of the robot device 9. The storage unit 42 can be composed of a non-temporary storage medium that can store information. For example, the storage unit 42 can be composed of a storage medium such as a volatile memory, a non-volatile memory, a magnetic storage medium, or an optical storage medium. The action program 41 for the robot device 9 to perform the spot welding operation is stored in the storage unit 42.

[0034] The operation processing device of the control device body 4 includes: an action control unit 43 that sends an action command. The action control unit 43 sends an action command for driving the robot 1 to the robot driving unit 44 according to the action program 41. The robot driving unit 44 includes an electrical circuit that drives the driving motor. The robot driving unit 44 supplies power to the robot driving device 21 according to the action command.

[0035] The operation control unit 43 sends an operation command to the tool drive unit 45 to drive the tool drive device 22. The tool drive unit 45 includes an electric circuit (electrode drive circuit) for driving a motor of a movable electrode. The tool drive unit 45 supplies power to the tool drive device 22 according to the operation command.

[0036] The motion control unit 43 corresponds to a processor that is driven according to the motion program 41 of the robot device 9. The processor reads the motion program 41 and executes the control specified in the motion program 41, thereby functioning as the motion control unit 43.

[0037] The welding timer 6 controls the current supply to the electrode 23 of the welding gun 5, such as the current size, the time for the current to flow, and the current change ratio. The welding timer 6 of this embodiment includes: a processing unit having a CPU as a processor. The processing unit of the welding timer 6 includes a welding control unit 62 for controlling the current. The processing unit of the welding timer 6 is formed to be able to communicate with the processing unit of the control device body 4. The welding control unit 62 receives an instruction to energize the electrode 23 from the operation control unit 43. The welding control unit 62 receives an instruction to energize, for example, according to the welding condition number.

[0038] The operation processing device of the welding timer 6 includes a storage unit 61 that stores information related to the control of the current supplied to the spot welding gun. The storage unit 61 can be composed of a non-temporary storage medium capable of storing information. For example, the storage unit 61 can be composed of a storage medium such as a volatile memory, a non-volatile memory, a magnetic storage medium, or an optical storage medium. The program for controlling the current of the welding timer 6 and the welding conditions 64, which are the conditions for welding, are stored in the storage unit 61.

[0039] The welding timer 6 includes a current supply unit 63 including a current supply circuit for supplying current to the electrode 23. The current supply unit 63 supplies power to the electrode 23 of the welding gun 5 according to a command from the welding control unit 62. The welding control unit 62 is equivalent to a processor driven according to a program for controlling current. The processor reads the program and implements the control specified in the program, thereby functioning as the welding control unit 62.

[0040] The control device 2 includes: a teaching operation panel 49 as an operation panel for the operator to manually operate the robot device 9. The teaching operation panel 49 includes: an input unit 49a, which inputs information related to the control of the robot device 9. The input unit 49a is composed of operating components such as a keyboard and a dial. The teaching operation panel 49 includes: a display unit 49b, which displays information related to the control of the robot device 9. The display unit 49b of this embodiment displays information related to welding. The display unit 49b is composed of a display panel such as a liquid crystal display panel or an organic EL (Electro Luminescence) display panel. In addition, when the display panel is composed of a display panel of a touch panel type, the display panel functions as an input unit and a display unit.

[0041] The operation processing device of the control device body 4 includes a condition operation unit 51 for operating welding conditions. The condition operation unit 51 includes a history information generation unit 52 for creating change history information of welding conditions. The change history information of this embodiment includes the value before the change and the value after the change of one or more items of welding conditions when the value of one or more items of welding conditions is changed. The change history information of this embodiment is not a relative value of the welding condition value, but is generated from the welding condition value (absolute value).

[0042] The condition operation unit 51 includes a restoration unit 53 that restores the values ​​of the items of the past welding conditions. The condition operation unit 51 includes a display control unit 54 that controls the image displayed on the display unit 49b of the teaching operation panel 49. The condition operation unit 51 has a condition setting unit 55 that sets the welding conditions for actual welding. The condition setting unit 55 sets the welding conditions for actual welding according to the operation of the input unit 49a by the operator. Each unit of the condition operation unit 51, the history information generation unit 52, the restoration unit 53, the display control unit 54, and the condition setting unit 55 is equivalent to a processor driven according to the action program 41. The processor reads the action program 41 and implements the control determined in the action program 41, thereby functioning as each unit.

[0043] The robot system in this embodiment has: an operation processing device 7 formed to be able to communicate with the operation processing device of the control device body 4. The operation processing device 7 is composed of a computer having a CPU as a processor. The operation processing device 7 has an input unit 71a for the operator to input information. The input unit 71a is composed of operating components such as a keyboard and a dial. In addition, the operation processing device 7 has a display unit 71b that displays information related to welding. The display unit 71b can be composed of any display panel that can display an image. The display unit 71b can be composed of a display panel such as a liquid crystal display panel or an organic EL display panel.

[0044] The operation processing device 7 includes a storage unit 72 for storing information related to welding. The storage unit 72 can be composed of a non-temporary storage medium capable of storing information. For example, the storage unit 72 can be composed of a storage medium such as a volatile memory, a non-volatile memory, a magnetic storage medium, or an optical storage medium. The operation processing device 7 has a processing unit 73 for processing information. The processing unit 73 is equivalent to a processor driven according to a program stored in the storage unit 72. The processor is driven according to the program, thereby functioning as the processing unit 73.

[0045] The storage unit 72 of the processing device 7 stores master data 76 of welding conditions. The master data 76 is reference data of welding conditions, and the values ​​of items (variables) included in the welding conditions in the reference data are composed of reference values. In the master data 76, all items are set to reference values. The operator can select welding conditions of any period as the master data 76. The storage unit 72 stores the master data 76 and the change history information 75 generated by the history information generating unit 52. The storage unit 72 stores the change history information 75 in association with the master data 76.

[0046] The calculation processing device 7 of this embodiment functions as a server that stores information related to welding conditions. In particular, the calculation processing device 7 functions as a server that stores change history information 75 and master data 76 of welding conditions. The processing unit 73 stores information related to welding in the storage unit 72 or reads it from the storage unit 72. In addition, the processing unit 73 transmits or receives information related to welding conditions to or from the condition operation unit 51.

[0047] The welding management device of this embodiment includes: a control device body 4, a teaching operation panel 49, and a calculation processing device 7 connected to the control device body 4 in a communicable manner. In this embodiment, the condition operation unit 51 is configured in the control device body 4, and the storage unit 72 storing the change history information 75 and the master data 76 is configured in the calculation processing device 7 connected to the control device body 4, but it is not limited to this mode. The storage unit 72 may also be configured in the calculation processing device of the control device body 4. That is, it is also possible that the processor of the control device body 4 has the function of the processing unit 73, and the storage unit 42 of the control device body 4 has the function of the storage unit 72 of the calculation processing device 7. In this case, the welding management device can be composed of the control device 2.

[0048] Alternatively, the processor of the calculation processing device 7 may execute the function of the condition operation unit 51. In other words, the calculation processing device 7 may have the function of the condition operation unit 51. In this case, the welding management device may be constituted by the calculation processing device 7.

[0049] The welding management device of this embodiment acquires and stores master data of welding conditions. Moreover, each time an operator changes the value of at least a part of the items included in the welding conditions, change history information of the welding conditions is created and stored. That is, the welding management device adds change history information each time there is a change in the welding conditions. Furthermore, the welding management device restores the past welding conditions based on the master data and the change history information through the operation of the operator. The welding management device can display the restored welding conditions on a display unit, or set them as the welding conditions for this time.

[0050] Figure 3 This is a schematic diagram for explaining the generation of master data. Figure 2 as well as Figure 3 , the display control unit 54 displays an image 81 containing the contents of the welding conditions on the display unit 49b of the teaching operation panel 49. The image 81 contains the names of the items of the welding conditions and the values ​​of the respective items. Here, as items of the welding conditions, 11 items such as pre-pressure (squeeze), up-slope control (up-slope) and the first power-on time are set. In addition, the time for pre-pressure, etc. is specified in units of cycles. Here, 1 cycle is the time corresponding to the control cycle in which the processor of the welding timer sends the current instruction. For example, 1 cycle is a few msec (milliseconds). Here, the pre-pressure is set to a time length of 50 cycles. In addition, the welding conditions include: a welding machine number for identifying the welding machine when there are multiple welding machines; a welding condition number for determining the desired welding condition based on multiple welding conditions.

[0051] When there are multiple robot devices, the welding machine number can be set for each robot device. Alternatively, the welding machine number can be set for each welding gun. For example, the welding condition number can be set for each welding point (welding point). Alternatively, if the workpiece thickness and material of the parts to be welded are the same, the welding condition with a common welding condition number can be used for multiple welding points.

[0052] The robot 1 makes the welding gun 5 be in the position and posture determined in the action program 41. In order to drive the welding gun 5, the action program 41 includes instructions related to the drive of the electrode 23. In addition, the action program 41 includes instructions related to welding conditions. For example, the action program 41 stipulates the welding conditions for supplying current to the welding gun 5 according to the welding condition number. When performing actual welding, the action control unit 43 obtains the instructions related to the drive of the electrode 23 from the action program 41. The action control unit 43 drives the movable electrode of the pair of electrodes 23 via the working tool drive unit 45. The tool drive device 22 uses the pair of electrodes 23 to pressurize the workpieces 91 and 92.

[0053] When the workpieces 91 and 92 are pressurized at a predetermined pressure, the motion control unit 43 transmits the welding condition number to the welding control unit 62. The storage unit 61 of the welding timer 6 stores the welding condition 64 for each welding condition number. The storage unit 61 stores the welding condition 64 in which all item values ​​are determined. The welding control unit 62 acquires the welding condition based on the welding condition number received from the motion control unit 43. The welding control unit 62 supplies current to the electrode 23 in a current supply pattern according to the welding condition. The components are melted and joined.

[0054] When the current supply according to the welding conditions is completed, the operation control unit 43 drives the tool driving device 22 via the working tool driving unit 45 so that the electrode 23 is separated from the workpieces 91 and 92. In this way, spot welding at one welding point can be performed.

[0055] The welding conditions are set in advance before the actual welding operation is performed. When setting the welding conditions, the operator can set the item values ​​of each welding condition by operating the input unit 49a of the teaching operation panel 49. The image 81 includes an information display area 85a and a button area 85b. Information related to the welding conditions is displayed in the information display area 85a. In the image 81, the items of all welding conditions and the item values ​​for the welding conditions can be set. In addition, the number of the welding machine and the welding condition number are displayed in the information display area 85a.

[0056] In this embodiment, when the item value of the welding condition is changed, a welding condition with a new welding condition number is not created, and the current welding condition number is maintained. However, welding conditions with two or more welding condition numbers may be created for one welding point. In this example, the welding condition of the first welding condition number of the first welding machine is described.

[0057] In the button area 85b, a plurality of buttons 82a to 82g are displayed for selecting items displayed in the information display area 85a or changing the set value of an item. The button 82a displays a menu screen for selecting the content to be displayed. The buttons 82b and 82c are buttons for moving the selected part upward or downward. The button 82d is a button for changing the value of the selected item. By pressing the button 82d, a screen for inputting a numerical value is displayed, and the item value of the welding condition can be changed.

[0058] The button 82e is a button for confirming the welding conditions changed by the operator. The buttons 82f and 82g are buttons for displaying the welding conditions of other welding machines or welding conditions of other welding condition numbers.

[0059] First, the operator registers master data that serves as reference data for welding conditions. The operator can set welding conditions for any period of time to the master data. For example, the operator can set the welding conditions created initially to the master data. Alternatively, the operator can set the welding conditions when welding is performed as desired to the master data.

[0060] The operator selects the button 82a of the menu of the image 81. The item to be registered as the master data is selected from the displayed menu screen. When the operator selects to register the master data, the condition operation unit 51 obtains the welding conditions at that time as the master data. At this time, the created date and time information is added to the welding conditions. Alternatively, the screen for setting the master data can be opened by pressing the button 82a of the menu to select a specified item. In addition, the master data can be generated by the operator inputting the values ​​of each item of the welding condition in the screen for setting the master data. The condition setting unit 55 of the condition operation unit 51 sends the welding conditions to the operation processing device 7. The processing unit 73 of the operation processing device 7 stores the welding conditions as the master data 76 in the storage unit 72.

[0061] exist Figure 3 In the example, the multiple items of the master data 76 are stored in the storage unit 72 of the operation processing device 7 in the form of a table. The master data 76 includes the stored date and time, the welding machine number, and the welding condition number. In this example, the preload 50 cycles, the rise control 3 cycles, the first power-on time 3 cycles, and the first current value 1500A are equivalent to the reference value. The method of storing the master data is not limited to the table form, and the value (reference value) for each item can be stored in any form.

[0062] The condition setting unit 55 sets the welding conditions of the master data 76 as the welding conditions for this welding. The condition setting unit 55 sends the welding conditions to the welding control unit 62 of the welding timer 6. The welding control unit 62 stores the master data as the initial welding conditions 64 in the storage unit 61.

[0063] Figure 4 This is an explanatory diagram showing the case where the value of at least a part of the items of welding conditions is changed. The operator presses the button 82a of the menu to select the item to change the welding conditions. The current item value of the welding condition is displayed in the information display area 85a of the display unit 49b. The operator selects the item to change the set value by operating the buttons 82b and 82c. Then, the operator presses the button 82d to display the image of the changed set value. The operator can change the set value of each item. In this example, the operator changes the set value, and the image 83 is displayed on the display unit 49b of the teaching operation panel 49.

[0064] The operator can change the item value of welding conditions for one or more items. Figure 3The image 81 of the master data is Figure 4 Here, the second power-on time, the second cooling time, the third power-on time, and the first current value are changed. When the change of each welding condition item is completed, the operator presses the button 82e to confirm the change of the welding condition.

[0065] Reference Figure 2 as well as Figure 4 , the history information generating unit 52 of the condition operating unit 51 obtains the item value of the changed welding condition and the date and time after the change. The history information generating unit 52 compares the welding condition of the image 81 before the change with the welding condition of the image 83 after the change. Here, the welding condition before the change is equivalent to the master data. The history information generating unit 52 detects whether the value of the item of the changed welding condition is the same as the value of the item of the welding condition before the change. The history information generating unit 52 detects the item whose value of the item of the changed welding condition is different from the value of the item of the welding condition before the change. Alternatively, the history information generating unit 52 may detect the item whose value of the item of the changed welding condition is different from the value of the item of the welding condition before the change according to the operation of the operator's input value.

[0066] The history information generating unit 52 generates the change history information 75a based on the detection result. The change history information 75a includes the date and time after the change, the number of the welding machine, and the welding condition number. The change history information 75a includes the number of the changed item and the name of the item. In addition, the change history information 75a includes the value before the change and the value after the change for each item. For example, if it is the second power-on time, it includes information that the change is from 5 cycles to 3 cycles. In this way, in the change history information of this embodiment, the set value of each item is stored as an absolute value. That is, the value set by the operator is stored.

[0067] The condition setting unit 55 sends the change history information generated by the history information generating unit 52 to the calculation processing device 7. The processing unit 73 stores the change history information 75a in the storage unit 72. The history information generating unit 52 generates the change history information 75 every time the value of at least a part of the items of the welding conditions is changed. The storage unit 72 of the calculation processing device 7 adds the new change history information to the currently stored change history information and stores it. In this way, the change history information is stored every time the welding conditions are changed.

[0068] Figure 5An explanatory diagram showing the update of welding conditions stored in the welding timer. The history information generating unit 52 generates the change history information 75c including the changed value for the changed item. In this case, the change history information 75c may not include the item value before the change. The condition setting unit 55 sends the change history information 75c to the welding control unit 62 of the welding timer 6. The welding control unit 62 updates the welding conditions 64 stored in the storage unit 61 based on the change history information 75c. The welding conditions 64 include the current values ​​of all items.

[0069] In this example, the second power-on time, the second cooling time, the third power-on time, and the first current value are updated. For items other than those included in the change history information 75c, the values ​​of the welding conditions stored last time are used. That is, the setting values ​​of the unchanged items are maintained. In addition, the stored date and time are updated to the date and time after the change. Figure 5 In the example, the welding conditions 64a are stored in a table format, but the present invention is not limited to this format. The storage unit 61 can store the welding conditions 64 in any format. For example, the welding conditions can be generated by predetermined symbols and numbers.

[0070] In this way, condition operation unit 51 transmits the changed value to welding timer 6. Welding control unit 62 updates welding condition 64 based on the changed value. Welding control unit 62 supplies current based on updated welding condition 64 when actually performing welding.

[0071] The operator can change the welding conditions at a desired time. For example, the operator can change the value of any item of the welding conditions according to the state of welding actually performed (quality of welding). In addition, the history information generating unit 52 generates change history information when the welding conditions are changed. The processing unit 73 of the operation processing device 7 receives the change history information and stores it in the storage unit 72. The welding control unit 62 of the welding timer 6 receives the change history information and updates the welding conditions 64. In this way, the operator can change the welding conditions multiple times until welding can be performed in a desired state.

[0072] In addition, the operator can also change the master data at any time. For example, the operator registers the initial welding conditions as the master data. Then, the operator changes the welding conditions to obtain the welding conditions with the best welding quality. The operator can store the welding conditions at this time as the master data.

[0073] When the master data is changed, the history information generation unit creates the change history information between the master data before the change and the master data after the change, as in the change history information of the welding conditions described above. That is, the history information generation unit compares the master data before the change with the master data after the change. The history information generation unit creates the change history information of the master data including the value of the item before the change and the value of the item after the change for the changed item. The change history information of the master data is stored in the storage unit 72 of the operation processing device 7. Afterwards, the processing unit 73 can delete the master data before the change. On the other hand, the operator sometimes wants to confirm the past change history information. Therefore, the normal change history information earlier than the time when the changed master data is created is not deleted but saved.

[0074] Next, the welding management device in this embodiment can calculate the welding conditions to be used at a predetermined time point based on the master data 76 and the change history information 75. For example, the welding management device can restore the values ​​of all items of the welding conditions at a desired time point in the past. Alternatively, the welding management device can calculate the values ​​of all items of the current welding conditions by the same method. Here, the restoration of the welding conditions at a desired time point in the past will be described.

[0075] Figure 6 The first figure is shown for explaining the restoration of welding conditions used in the past. Figure 7 The second figure is a diagram for explaining the restoration of the welding conditions used in the past. Figure 6 The data of the operation processing device 7 is calculated in Figure 7 The teaching operation panel 49 displays the restored welding condition values. Figure 2 , Figure 6 as well as Figure 7 The storage unit 72 of the processing device 7 stores the master data 76 and the change history information 75 b to which the history information is added each time the welding conditions are changed. Figure 6 The change history information 75b shown includes the history information changed on March 10, 2022 and the history information changed on March 15, 2022. The current welding conditions are the conditions after the change on March 15, 2022.

[0076] The restoring unit 53 of the condition operation unit 51 restores the welding conditions used in the past based on the master data 76 and the change history information 75b. The display unit 49b of the teaching operation panel 49 displays an image 84 including the current welding condition item values ​​and the restored item values ​​at the time selected by the operator.

[0077] The operator specifies the date and time of past changes included in the change history information. The restoration unit 53 restores the values ​​of at least a part of the items of the welding conditions at the time point specified by the operator's operation. The restoration unit 53 extracts the change history information from the date and time when the master data 76 was created to the specified date and time. The restoration unit 53 restores the welding conditions changed at the specified date and time based on the master data 76 and the change history information up to the specified date and time. In this example, the past date and time specified by the operator is March 10, 2022, and the welding conditions changed on that day are calculated and displayed.

[0078] In addition, the item values ​​of the current welding conditions can also be derived by the same control as this control. That is, even if the current welding conditions are not acquired from the welding timer 6, the current welding conditions can be calculated from the master data 76 and the change history information 75.

[0079] The operator selects the item of the restoration operation by, for example, selecting the menu button 87a on the teaching operation panel 49. By selecting the button 87f, an image listing the dates and times when changes included in the change history information were made is displayed. The operator selects the date and time for restoring the past welding conditions.

[0080] The restoration unit 53 calculates the value of each item so that the welding condition becomes the welding condition after the change at the date and time specified by the operator. For example, when the welding condition is changed multiple times from the current time to the specified time and date, the restoration unit 53 can derive the value obtained by returning all the item values ​​to the values ​​at the specified time and date.

[0081] The display unit 49b can display the item values ​​used in the past restored by the restoration unit 53. In this example, the display control unit 54 displays a list of the item values ​​of the welding conditions used in the past and the item values ​​of the current welding conditions on the display unit 49b for the items of the welding conditions whose values ​​have been changed by restoration. That is, the items changed by restoration are extracted, and the current values ​​before restoration and the values ​​after restoration are displayed in a row. By implementing this control, the operator can easily grasp all the items of the welding conditions that have been changed from the specified date and time to the present.

[0082] As an image when performing the restoration operation, it is not limited to this mode, and all welding condition items may be displayed. That is, the welding condition items that have not been changed from the current time to the specified date and time may be displayed. In the welding management device of this embodiment, the operator can easily obtain the items of the changed welding conditions and the changed values. Therefore, the operator can easily manage the welding conditions.

[0083] The operator can easily understand the items that have changed by restoring by observing the image 84. In addition, the operator can also easily understand the items that have changed from the specified date and time to the present. The operator determines whether the welding conditions at the specified date and time can be restored. When changing the welding conditions, the operator selects the welding conditions of another date and time by pressing the button 87f.

[0084] When the operator determines the welding condition to be restored, he presses the button 87d. The condition setting unit 55 sets the restored welding condition as the welding condition for this welding. The history information generation unit 52 generates the change history information based on the value of the current welding condition and the value of the changed welding condition. The condition setting unit 55 sends the change history information to the operation processing device 7. The storage unit 72 of the operation processing device 7 stores the change history information. The condition setting unit 55 sends the change history information including the changed item value to the welding control unit 62. The welding control unit 62 updates the welding condition 64 stored in the storage unit 61. In addition, the history information generation unit may add information indicating that the welding condition is restored to the past to the change history information.

[0085] Thus, in the present embodiment, the restoration unit 53 restores the values ​​of at least some items to the welding conditions at the time point specified by the operator's operation. The restoration unit 53 obtains the change history information 75 and the master data 76 from the calculation processing device 7, and restores the past welding conditions. The display control unit 54 can display the item values ​​used in the past calculated by the restoration unit 53 on the display unit 49b. The operator can easily compare the past welding conditions with the current welding conditions.

[0086] For example, the quality of welding may deteriorate at a predetermined time. The operator can refer to the changes in the past welding conditions to find out the cause of the deterioration in welding quality. In addition, when the change in welding conditions is the cause of the deterioration in welding quality, the operator can restore the welding conditions to the welding conditions before the deterioration in welding quality.

[0087] In this embodiment, the control to restore to the welding condition after the previous change is performed, but the present invention is not limited to this method. The control to restore to the welding conditions before two or more changes may also be performed. In addition, the items to be changed are not limited to a part of the welding conditions, and all the items may be changed.

[0088] In this embodiment, master data and change history information starting from the master data are stored to manage welding conditions. In addition, actual values ​​are stored as change history information instead of the difference between the value before the change and the value after the change. By adopting this structure, the welding conditions at a desired time point can be reliably restored. For example, when there is no master data but only differential information, when a part of the differential information is lost for some reason, the welding conditions may not be restored. Or, when the differential information is changed for some reason, the welding conditions may not be restored. However, by having master data and change history information represented by absolute values, the welding conditions at any time point can be reliably restored.

[0089] Figure 8 This is an example of an image displayed on the display unit of the teaching operation panel when a part of the welding condition items is restored. The operator selects button 87g to open another screen and select a desired item from the welding condition items. For example, another screen displays a list of welding condition items that have been changed since the creation of the master data. The operator can select a desired item from the list of items. In image 86, the operator selects the second power-on time and the second cooling time from the items that have been changed in the past.

[0090] The restoration unit 53 can extract the changed date and time and the value of the item from the change history information for the item selected by the operator. Here, two items and their values ​​set on March 10, 2022 and March 3, 2022 are displayed. The display control unit 54 can display the current value of the selected item and the value of the selected item at each changed date and time.

[0091] The operator can select to change the date and time by operating buttons 87b and 87c. Furthermore, the operator can restore the selected item to the value of the selected date and time by pressing the confirmation button 87d. The current values ​​of items other than the selected item are maintained.

[0092] In this way, the restoration unit 53 can restore the values ​​of some items among the multiple items that were changed in the past. The restoration unit 53 can restore some items included in the welding conditions used in the past at a predetermined time point. The condition setting unit 55 can set the values ​​of some items of the welding conditions restored in the past as the values ​​of some items of the welding conditions for this welding.

[0093] At this time, the history information generating unit 52 also generates the change history information. The condition setting unit 55 sends the change history information including the item value before the change and the item value after the change to the processing unit 73 of the arithmetic processing device 7. The processing unit 73 stores the change history information in the storage unit 72. The condition setting unit 55 sends the change history information including the changed item value to the welding control unit 62. The welding control unit 62 updates the welding condition 64 with the changed value. In this way, the welding management device of the present embodiment can perform an operation of restoring the value of a part of the items of the welding condition that the operator is concerned about.

[0094] The welding management device of this embodiment can easily manage changes in welding conditions. Therefore, it is easy to identify the cause, repair and restore the welding quality when there is a problem. For example, it is easy to determine the change in welding conditions that caused the problem and return to the original state.

[0095] Fig. 9 This is a block diagram of another robot system in the present embodiment. Another robot system includes a plurality of robot devices 9a to 9d as welding devices. In this example, the robot system includes four robot devices 9a to 9d whose welding machine numbers are 1 to 4.

[0096] In the above-mentioned robot system, the operation processing device 7 is directly connected to the control device 2 of the robot device 9. In contrast, in other robot systems, the storage unit of the operation processing device 7 that functions as a server is connected to a plurality of robot devices 9a to 9d via an electrical communication line. The operation processing device 7 is connected to the control devices 2 of the robot devices 9a to 9d via an intranet such as a LAN (Local Area Network) or a network such as the Internet.

[0097] In particular, the calculation processing device 7 is configured to be able to communicate with the condition operation unit of the robot device 9a. The storage unit of the calculation processing device 7 acquires and stores information of the robot devices 9a to 9c such as welding conditions from each control device 2. In particular, the condition setting unit of the control device 2 sends the change history information of the welding conditions and the master data to the calculation processing device 7.

[0098] In other robot systems, welding conditions can be managed for multiple robot devices at once. For example, change history information of welding conditions can be managed at once. Alternatively, changes in item values ​​of welding conditions can be investigated for multiple robot devices at once. As a result, when problems occur in welding quality, it is easy to detect problem points. Alternatively, when multiple robot devices are configured in one production line, it is easy to detect problem points for the entire production line.

[0099] Preferably, the robot devices 9a to 9d have the same welding method for the thickness, shape, material, etc. of the workpiece for at least a portion of the welding points. That is, preferably, the robot devices 9a to 9d can use welding conditions with a common welding condition number for at least a portion of the welding points. The calculation processing device 7 can send the optimal welding conditions for the welding points of the same method to all the robot devices.

[0100] In this embodiment, a robot device having a spot welding gun and a robot equipped with the spot welding gun is used as an example for description, but the present invention is not limited to this method. The welding management device in this embodiment can be applied to the management of any spot welding device. For example, the spot welding device can also be formed as follows: the spot welding gun is fixed and the workpiece is moved.

[0101] The above-mentioned embodiments can be combined appropriately. In the above-mentioned figures, the same or equivalent parts are marked with the same symbols. In addition, the above-mentioned embodiments are illustrative and do not limit the invention. In addition, in the embodiments, changes of the embodiments shown in the claims are included.

[0102] Explanation of symbols

[0103] 1. Robot

[0104] 2 Control device

[0105] 4 Control device body

[0106] 5. Welding gun

[0107] 6 Welding timer

[0108] 7. Processing device

[0109] 9. 9a. 9b. 9c. 9d. Robotic devices

[0110] 42 Storage

[0111] 43 Motion Control Unit

[0112] 49 Teaching operation panel

[0113] 49a Input section

[0114] 49b Display unit

[0115] 52 History Information Generation Department

[0116] 53 Restoration Department

[0117] 54 Display control unit

[0118] 55 Condition Setting Section

[0119] 72 Storage

[0120] 73 Processing Department

[0121] 75 Change History Information

[0122] 75a~75c change history information

[0123] 76Master data.

Claims

1. A welding management device for managing welding conditions of spot welding, characterized in that: The welding management device has: a storage unit storing reference data of welding conditions, wherein values ​​of items included in the welding conditions in the reference data are composed of reference values; as well as a history information generating unit for generating change history information including values ​​before and after the change of one or more items of welding conditions when the values ​​of the one or more items of welding conditions are changed; The storage unit stores the change history information generated by the history information generation unit together with the reference data.

2. The welding management device according to claim 1, characterized in that: The welding management device includes a restoring unit that restores the values ​​of items of past welding conditions. The restoration unit restores past welding conditions based on the reference data and the change history information.

3. The welding management device according to claim 2, characterized in that: The welding management device includes: a condition setting unit that sets welding conditions for actual welding; The restoring unit restores the welding conditions used in the past at a predetermined time point. The condition setting unit sets the welding conditions restored by the restoration unit as welding conditions for current welding.

4. The welding management device according to claim 3, characterized in that: The welding management device comprises: a display unit which displays information related to welding; The display unit displays a list of values ​​of welding condition items used in the past and values ​​of current welding condition items for items of welding condition whose values ​​have been changed.

5. The welding management device according to claim 2, characterized in that: The welding management device includes: a condition setting unit that sets welding conditions for actual welding; The restoration unit restores a part of items included in the welding conditions used in the past at a predetermined time point. The condition setting unit sets values ​​of some items of the welding conditions restored by the restoration unit as welding conditions for current welding.

6. The welding management device according to claim 2, characterized in that: The welding management device comprises: a display unit which displays information related to welding; The restoring unit restores the values ​​of at least a part of the items of the welding conditions at a time point specified by an operator's operation. The display unit displays the value of the item used in the past restored by the restoration unit.

7. The welding management device according to any one of claims 1 to 6, characterized in that: The storage unit is connected to a plurality of welding devices via a network. The storage unit is configured to store information on a plurality of welding devices.

Images