Arc welding device and welding condition setting method

Abstract

An arc welding device 70 comprises a welding power source 10, a welding torch 40, an electrode 43, a second control unit 22, and a filler-feeding motor 25. The welding power source 10 has a welding navigation unit 13, a first control unit 15, and an output unit 16. The welding navigation unit 13 calculates a welding current command value and an operation parameter of the filler-feeding motor 25 in accordance with at least the material and the plate thickness of a base material 80. The first control unit 15 controls the output unit 16 on the basis of a current control command. The second control unit 22 controls the filler-feeding motor 25 on the basis of a filler-feeding control command. The current control command includes the welding current command value, and the filler-feeding control command includes part of the operation parameter.

Description

Arc welding device and welding condition setting method

[0001] The present disclosure relates to an arc welding device and a welding condition setting method.

[0002] Arc welding requires the setting of many control parameters. For example, it is necessary to set the welding wire feed rate, welding current command value, and, in the case of pulse welding, the pulse frequency. These control parameters are often set manually by the welding operator based on the results of test welding, etc. However, it is difficult for welding operators who do not have sufficient understanding of welding techniques or experience in welding work to set these control parameters appropriately.

[0003] Therefore, a method has been proposed in which a welding machine is equipped with a navigation function, and recommended welding values ​​such as a welding current command value and a welding voltage value suitable for welding are calculated and displayed simply by inputting basic values ​​for welding, such as the thickness and material of the base material, into the welding machine (see, for example, Patent Documents 1 and 2).

[0004] International Publication No. WO 2016 / 075874 International Publication No. WO 2016 / 075883

[0005] There are several types of arc welding, one of which is Tungsten Inert Gas (TIG) welding. TIG welding is a non-consumable electrode type of arc welding. However, if there is a gap or misalignment in the joint of the base material, the weld may not be filled properly, resulting in undercuts or holes.

[0006] Therefore, in conventional TIG welding, a filler metal (also called a filler material) made of the same material as the base metal is inserted into the arc generated between the base metal and the electrode, and gaps, misalignments, etc. are filled with the molten filler metal (hereinafter also called a TIG filler welding method).

[0007] In TIG filler welding, filler is fed from a filler feed device toward the base material. In this case, unlike consumable electrode arc welding, the setting of the filler feed rate is not directly linked to the welding current command value of the welding power source, and the welder must manually set the filler feed rate. However, if the welder's knowledge and experience are insufficient, it is difficult to set the appropriate feed rate, and the confirmation work for setting it requires a lot of time. Furthermore, due to the aging of skilled workers, it is becoming more difficult to secure welders who can perform appropriate arc welding.

[0008] The present disclosure has been made in consideration of the above points, and its purpose is to provide an arc welding device and a welding condition setting method that can automatically set an appropriate filler feed rate in TIG filler welding by inputting basic parameters for welding.

[0009] In order to achieve the above object, an arc welding apparatus according to the present disclosure includes at least a welding power source, a welding torch connected to the welding power source, an electrode held by the welding torch, and a filler supply device that supplies filler toward a welding point on a base metal, the welding power source having at least a first input unit, a memory unit, a welding navigation unit, a first display unit, a first control unit, an output unit, and a first communication unit, the memory unit at least temporarily stores first welding conditions input from the first input unit, the welding navigation unit calculates a welding current command value in accordance with at least the material and thickness of the base metal among the first welding conditions when the filler is not used, and in accordance with at least the material and thickness of the base metal when the filler is used, and calculates operating parameters of the filler supply device, and the first display unit displays at least the calculation results of the welding navigation unit the first control unit controls the output unit based on at least the welding current command value, the output unit outputs a welding current to the electrode based on a current control command output from the first control unit, the first communication unit transmits the filler feed control command output from the first control unit to the filler supply device, the filler supply device has at least a second control unit, a second communication unit, and a filler feed motor, the second control unit controls operation of the filler feed motor based on at least the filler feed control command, the second communication unit receives the filler feed control command transmitted from the first communication unit, the filler feed motor feeds the filler based on a motor control command output from the second control unit, the current control command includes at least the welding current command value, and the filler feed control command includes at least a part of the operation parameters.

[0010] The welding condition setting method according to the present disclosure is a welding condition setting method for the arc welding apparatus, comprising at least a first step of selecting whether or not to use the filler, a second step of setting the material and thickness of the base metal and whether or not the welding current is a pulse current, and a third step of automatically setting at least the welding current command value in accordance with the settings in the second step, and further comprising a fourth step of automatically setting the operating parameters in accordance with the settings in the second step if it is selected in the first step that the filler is to be used.

[0011] According to the present disclosure, by inputting basic parameters for welding, it is possible to automatically set an appropriate welding current value, a filler feed rate, or both. This allows even welding workers with insufficient knowledge and experience to perform welding appropriately. It also makes it possible to stabilize welding quality.

[0012] FIG. 1 is a schematic diagram of an arc welding apparatus according to an embodiment. FIG. 2 is a functional block diagram of essential components of the arc welding apparatus. FIG. 3 is a flowchart showing a welding condition setting procedure. FIG. 4A is an example of an input screen of the first display unit when inputting whether or not a filler is used. FIG. 4B is an example of an input screen of the first display unit when inputting the material of the base material. FIG. 4C is an example of an input screen of the first display unit when inputting the thickness of the first plate material. FIG. 4D is an example of an input screen of the first display unit when inputting the thickness of the second plate material. FIG. 4E is an example of an input screen of the first display unit when inputting the shape of a joint. FIG. 4F is an example of an input screen of the first display unit when inputting pulse settings. FIG. 5A is an example of a display of the calculation results of the welding navigation unit and second welding conditions when a filler is used. FIG. 5B is an example of a display of the calculation results of the welding navigation unit and second welding conditions when a filler is not used. FIG. 6 is a diagram showing a list of operating parameters automatically set by the filler feed motor. Fig. 7 is a time chart showing various output waveforms when the filler feeding mode is the continuous feeding mode. Fig. 8 is a time chart showing various output waveforms when the filler feeding mode is the first intermittent feeding mode. Fig. 9 is a time chart showing various output waveforms when the filler feeding mode is the pulse synchronous mode. Fig. 10 is a time chart showing various output waveforms when the filler feeding mode is the second intermittent feeding mode.

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0014] (Embodiment) [1: Schematic Configuration of Arc Welding Apparatus] Fig. 1 is a schematic configuration diagram of an arc welding apparatus according to an embodiment. Fig. 2 is a functional block diagram of the main parts of the arc welding apparatus.

[0015] As shown in Fig. 1, arc welding apparatus 70 includes welding power source 10, filler material supply device 20, and remote controller 30. For ease of explanation, the shapes of welding torch 40, guide holder 42, and electrode 43 are simplified in Fig. 1. Furthermore, the power source that drives filler material feed motor 25 in filler material supply device 20 is not shown.

[0016] Arc welding device 70 also has gas cylinder 50, and shielding gas is supplied from gas cylinder 50 to welding torch 40 via gas piping 65. The shielding gas prevents molten base material 80 and filler 27 from reacting with air during arc welding.

[0017] [1-1: Configuration of Welding Power Source] Welding power source 10 has first output terminal 10a, second output terminal 10b, first control terminal 10c, and second control terminal 10d. First output terminal 10a is electrically connected to electrode 43 held by welding torch 40 via first power cable 61 and composite cable 60. Second output terminal 10b is connected to base material 80 via second power cable 62. First control terminal 10c is connected to motor controller 21 of filler supply device 20 via first control cable 63. Second control terminal 10d is connected to remote controller 30 via second control cable 64. Composite cable 60 is formed by combining first power cable 61 and gas piping 65.

[0018] Welding power source 10 has one or more central processing units (CPUs), not shown. As shown in FIG. 2 , welding power source 10 also has multiple functional blocks. Specifically, welding power source 10 has first input unit 11, memory unit 12, welding navigation unit 13, first display unit 14, first control unit 15, output unit 16, and first communication unit 17. Of these functional blocks, welding navigation unit 13 and first control unit 15 are realized as functional blocks by running a predetermined program on the CPU. Welding navigation unit 13 and first control unit 15 may also be realized as functional blocks on different CPUs.

[0019] The first input unit 11 is configured with input devices such as a jog dial and operation buttons. The first input unit 11 may be configured with a touch panel. In this case, the first input unit 11 and the first display unit 14 may be integrated. The welding operator operates the first input unit 11 to input basic parameters for TIG welding. The parameters in this case are the material and thickness of the base material 80, the shape of the joint, whether the welding current is a pulse current (hereinafter referred to as the pulse setting), and whether or not a filler 27 is used (see FIGS. 3 and 4A to 4F). Hereinafter, these conditions may be collectively referred to as the first welding conditions.

[0020] The storage unit 12 is configured with a semiconductor memory such as a read-only memory (ROM), a random access memory (RAM), or a solid-state drive (SSD), or a hard disk drive (HDD), or both. The storage unit 12 stores control programs for various devices used in TIG welding. The storage unit 12 also temporarily stores specific numerical values ​​related to the first welding conditions input from the first input unit 11. The storage unit 12 also stores second welding conditions, which will be described later, in a table format or a text format depending on the first welding conditions.

[0021] The welding navigation unit 13 calculates a welding current command value according to at least the thickness and material of the base material 80, which are among the first welding conditions. Here, the welding current command value is a control target value for the welding current flowing through the electrode 43. Furthermore, if the use of filler 27 is selected under the first welding conditions, the welding navigation unit 13 calculates the welding current command value as well as operating parameters of the filler feeder 20. The operating parameters will be described later. Note that the shape of the joint described above may be taken into consideration when calculating the welding current command value.

[0022] First display unit 14 is configured with a display device such as a liquid crystal display or an organic EL display. As described above, first display unit 14 may also be configured with a touch panel. First display unit 14 displays at least the calculation results of welding navigation unit 13. First display unit 14 also displays an input screen for inputting the first welding conditions (see FIGS. 4A and 4F). First display unit 14 may also display the second welding conditions along with the calculation results of welding navigation unit 13 (see FIGS. 5A and 5B).

[0023] First control unit 15 controls the welding current output from output unit 16 based on the welding current command value. Furthermore, first control unit 15 reads and executes a control program stored in storage unit 12 in response to operation of first input unit 11, and controls the operation of output unit 16 and filler supply device 20. Specifically, first control unit 15 outputs a current control command to output unit 16. Furthermore, when use of filler 27 is selected, first control unit 15 outputs a filler feed control command to motor controller 21 of filler supply device 20.

[0024] Output unit 16 is a power converter including a rectifier, a transformer, a switching element, etc. (none of which are shown). Output unit 16 outputs a welding current to electrode 43 based on a current control command output from first control unit 15. The current control command includes information such as a welding current command value and a pulse frequency if the welding current is a pulse current.

[0025] The first communication unit 17 is a communication circuit having an interface function. The first communication unit 17 transmits a filler feed control command output from the first control unit 15 to the second communication unit 23 of the filler supply device 20. The filler feed control command includes at least some of the operating parameters of the filler supply device 20 described above.

[0026] When the first welding conditions are input from the remote controller 30, the first communication unit 17 transmits the first welding conditions transmitted from the third communication unit 33 of the remote controller 30 to at least one of the memory unit 12 and the welding navigation unit 13.

[0027] Note that communication between the first communication unit 17 and the second communication unit 23 is performed via a first control cable 63, and the communication format therebetween is digital communication. For example, the communication format is UART (Universal Asynchronous Receiver Transmitter), and digital signals (physical layer standard: RS422) are communicated between the first communication unit 17 and the second communication unit 23. Similarly, communication between the first communication unit 17 and the third communication unit 33 is performed via a second control cable 64, and the communication format therebetween is digital communication. Note that in this embodiment, data transmission and reception between the first communication unit 17 and the second communication unit 23 is wired communication via the first control cable 63, and data transmission and reception between the first communication unit 17 and the third communication unit 33 is wired communication via the second control cable 64.

[0028] However, this is not particularly limited, and data transmission and reception between the first communication unit 17 and the second communication unit 23, and data transmission and reception between the first communication unit 17 and the third communication unit 33 may be wireless communication. In this case, the first communication unit 17, the second communication unit, and the third communication unit 33 each have a wireless communication function. Furthermore, when data transmission and reception are performed via wireless communication, the first control cable 63 and the second control cable 64 may be omitted. Furthermore, the filler supply device 20 may also include the function of the remote controller 30.

[0029] [1-2: Configuration of Filler Supply Device] The filler supply device 20 has a motor controller 21, a filler storage unit 24, a filler feed motor 25, a filler guide 26, and a filler switch 28. The motor controller 21 has a second control unit 22 and the second communication unit 23 described above.

[0030] The second control unit 22 is realized as a functional block by executing the above-mentioned filler control command on the CPU mounted on the motor controller 21. The second control unit 22 controls the operation of the filler feed motor 25 based on the filler feed control command. Specifically, the second control unit 22 generates a motor control command based on the filler feed control command and controls the operation of the filler feed motor 25 based on the motor control command.

[0031] As described above, the filler control command includes, among the operating parameters, information relating to the operation of the filler feed motor 25. The operating parameters include at least one of the feed speed of the filler 27 (hereinafter referred to as the filler feed speed), the feed frequency of the filler 27, and whether or not crater processing is performed. The operating parameters also include other parameters, which will be described later.

[0032] The second communication unit 23 has the same hardware configuration as the first communication unit 17 , and receives the filler feed control command transmitted from the first communication unit 17 and transmits it to the second control unit 22 .

[0033] The filler storage section 24 is a container that stores the filler 27. In many cases, the filler 27 is stored in the filler storage section 24 in a state where it is wound around a reel (not shown).

[0034] The filler feed motor 25 feeds the filler 27 toward the base material 80 based on a motor control command output from the second control unit 22 .

[0035] Filler guide 26 is a jig that holds filler 27 drawn from filler feed motor 25 so that the tip of filler 27 enters an arc (not shown) generated between base metal 80 and electrode 43. Filler 27 is held by filler guide 26 so that it can move linearly. Filler guide 26 is held by a guide holder 42 attached to welding torch 40. In this case, filler guide 26 is attached and fixed to guide holder 42 so that the welded surface of base metal 80 and the feed direction of filler 27 form a predetermined angle θ2. In the following description, angle θ2 will be referred to as the filler insertion angle θ2.

[0036] The filler switch 28 is connected to the motor controller 21. When the filler switch 28 is operated, the filler feed motor 25 stops operating after a preset period of time has elapsed. As will be described later, the feed speed of the filler 27 by the filler feed motor 25 can also be changed by operating the filler switch 28.

[0037] [1-3: Configuration of Remote Controller] Remote controller 30 has second input unit 31, second display unit 32, and third communication unit 33. Second input unit 31 has the same hardware configuration as first input unit 11, and third communication unit 33 has the same hardware configuration as first communication unit 17. When a welding operator operates second input unit 31 to input first welding conditions, the first welding conditions are transmitted to first communication unit 17 via third communication unit 33.

[0038] As will be described later, when base material 80 is TIG welded in accordance with the calculation results of welding navigation unit 13, if the appearance or quality of the welded portion does not satisfy predetermined required specifications, the calculation results must be corrected. In this case, the corrected numerical values ​​are input from first input unit 11 or second input unit 31 and temporarily stored in memory unit 12.

[0039] [1-4: Other Configurations] In this embodiment, a welding operator performs TIG welding while holding welding torch 40. Welding torch 40 has torch switch 41. When the welding operator operates torch switch 41, a welding current is output from output unit 16 to electrode 43, and filler feed motor 25 also operates in conjunction with this. When the welding operator operates torch switch 41, the output of the welding current is stopped. When the welding operator wishes to stop the operation of filler feed motor 25 and stop the supply of filler 27, the aforementioned filler switch 28 is operated.

[0040] The electrode 43 is made of, for example, tungsten or a tungsten alloy and is a columnar member whose tip forms an angle θ1 (0°<θ1<90°) in a cross-sectional view. A welding current output from the output unit 16 flows through the electrode 43. When the welding current reaches a predetermined value or greater, an arc is generated between the electrode 43 and the surface of the base material 80. The arc heats the base material 80, causing a portion to melt and then solidify, forming a weld (not shown). Furthermore, if a filler 27 is used, the filler 27 melts when exposed to the arc. The filler 27 is made of the same material as the base material 80 or a metal that is the same as the main constituent metal of the base material 80. The molten filler 27 adheres to the base material 80, allowing the weld to rise to a desired height. Furthermore, the strength and appearance of the weld can be maintained as desired.

[0041] [2: Welding Condition Setting Method] Figure 3 is a flowchart showing the welding condition setting procedure. Figure 4A is an example of an input screen of the first display unit when inputting whether or not a filler is used. Figure 4B is an example of an input screen of the first display unit when inputting the material of the base metal. Figure 4C is an example of an input screen of the first display unit when inputting the thickness of the first plate material. Figure 4D is an example of an input screen of the first display unit when inputting the thickness of the second plate material. Figure 4E is an example of an input screen of the first display unit when inputting the shape of the joint. Figure 4F is an example of an input screen of the first display unit when inputting pulse settings.

[0042] 5A and 5B show examples of displaying the calculation results of the welding navigation unit and the second welding conditions when a filler is used and when no filler is used, respectively.

[0043] In this embodiment, the main welding conditions are set by operating the first input unit 11 of the welding power source 10. In this case, the first input unit 11 is a touch panel. Alternatively, as described above, the main welding conditions may be set by operating the second input unit 31 of the remote controller 30.

[0044] When performing TIG welding, the welding operator selects whether or not to use the filler 27 (step S1). If the selection result in step S1 is affirmative, i.e., if the filler 27 is to be used, the process proceeds to step S2, and if the selection result in step S1 is negative, i.e., if the filler 27 is not to be used, the process proceeds to step S10.

[0045] In step S2, the welding operator operates the first input unit 11 to input the first welding conditions described above. This will be explained below with reference to Figures 4A to 4F. In this case, the base material 80 has a T-shaped joint structure between a first plate material 81 and a second plate material 82 made of stainless steel (see Figure 4E).

[0046] 4A, input whether or not to use the filler 27. For example, touch the arrow displayed on the input screen to display whether or not to use the filler 27, and then touch the return key displayed on the input screen to confirm the selection.

[0047] As shown in Fig. 4B, the material of the base material 80 is input. In the example shown in Fig. 4B, a list of materials of the base material 80 is displayed on the input screen. This list is saved in advance in the storage unit 12. After touching and selecting the material to be welded, in this case stainless steel, the user touches the return key displayed on the input screen to confirm the selection.

[0048] As shown in FIG. 4C , the thickness of the first plate material 81 is input. In the example shown in FIG. 4C , the initial plate thickness (=1.0 mm) of the first plate material 81 is displayed on the input screen, with a + mark above it and a - mark below it. If you want to set the plate thickness of the first plate material 81 to 3.0 mm, touch the + mark multiple times. Then, touch the return key displayed on the input screen to confirm the input. If you want to set the plate thickness of the first plate material 81 to 1.3 mm, touch the display of "1.0 mm" and then touch the + mark multiple times. Then, touch the return key displayed on the input screen to confirm the input. As shown in FIG. 4D , the plate thickness of the second plate material 82 is input. The method for inputting the plate thickness of the second plate material 82 is the same as the method for inputting the plate thickness of the first plate material 81 described above.

[0049] As shown in Fig. 4E, the joint structure of the base material 80 is selected. In the example shown in Fig. 4B, the joint structure of the base material 80 is displayed on the input screen. A plurality of types of joint structures are stored in advance in the storage unit 12. Each time the arrow displayed on the input screen is touched, the joint structures are displayed in sequence. After the joint structure to be welded is displayed, the return key displayed on the input screen is touched to confirm the selection.

[0050] As shown in Fig. 4F, the pulse setting is selected. For example, the arrow displayed on the input screen is touched to display whether the welding current is a pulse current or not, and then the return key displayed on the input screen is touched to confirm the selection.

[0051] 4A to 4F do not need to be displayed in this order, and for example, the pulse setting selection may be performed first. Also, the input screens and the input method for each item shown in FIGS. 4A to 4F are merely examples, and are not particularly limited to the above-described method.

[0052] When step S2 is executed, welding navigation unit 13 calculates a welding current command value in accordance with the input contents of the first welding conditions. Furthermore, welding navigation unit 13 selects some of the operating parameters for filler feed motor 25 in accordance with the input contents of the first welding conditions and calculates the remaining parameters (step S3). Furthermore, welding navigation unit 13 automatically sets these values ​​and the selection results. That is, welding navigation unit 13 sets the calculated welding current command value in first control unit 15 (step S4) and transmits the operating parameters of filler feed motor 25 to second communication unit 23 of motor controller 21 via first communication unit 17. The transmitted operating parameters are set in second control unit 22, and the operating conditions of filler feed motor 25 are determined (step S5).

[0053] Note that there are cases where a calculation formula according to the material and thickness of the base material 80 is stored in the storage unit 12 and the welding current command value is calculated. There are also cases where a table or text file describing the relationship between the material and thickness of the base material 80 and the welding current command value is stored in the storage unit 12 and the welding current command value is calculated. In either case, the shape of the joint is taken into consideration as necessary.

[0054] Similarly, calculations of the operating parameters are performed using formulas, tables, or text files. However, in this case, not only the material and thickness of the base material 80 but also the welding current command value and the pulse frequency when the welding current is a pulse current are taken into consideration. Furthermore, the shape of the joint is also taken into consideration, if necessary.

[0055] 5A, welding navigation unit 13 or first control unit 15 causes first display unit 14 to display the welding current command value and operating parameters calculated and selected in step S2. Welding navigation unit 13 or first control unit 15 also causes first display unit 14 to display peripheral device settings (step S6). Here, the peripheral device settings refer to fixed and recommended welding conditions stored in advance in memory unit 12. In the following description, these peripheral device settings may be referred to as second welding conditions.

[0056] 5A, the second welding conditions include the electrode diameter, which is the diameter of the electrode 43, and the electrode tip angle θ1 described above. These conditions are basically the initial settings of the arc welding device 70, and if these conditions are to be changed, the electrode 43 must be replaced.

[0057] The second welding conditions also include the flow rate of the shielding gas, the filler diameter which is the diameter of filler 27, the electrode-base metal distance (b in FIG. 5A ) which is the distance between the welded surface of base metal 80 and the tip of electrode 43, and the above-mentioned filler insertion angle θ2 (d in FIG. 5A ). The second welding conditions also include the electrode protrusion length (a in FIG. 5A ) which is the protrusion length of electrode 43 from the tip of welding torch 40, and the electrode-filler distance (c in FIG. 5A ) which is the distance between the tip of electrode 43 and the tip of filler 27. These conditions are recommended conditions during welding.

[0058] The welding current command value and some of the operating parameters of the filler feed motor 25, as well as the numerical values ​​of the second welding conditions other than the electrode diameter and electrode tip angle θ1, can be modified by operating the first input unit 11. However, with regard to the second welding conditions, in addition to modifying the numerical values, the welding operator must also adjust the actual welding conditions by adjusting the valve of the gas cylinder 50, replacing the filler 27, and modifying the layout of the filler supply device 20 and the welding torch 40. Details of the operating parameters of the filler feed motor 25 will be described later. After step S6 is performed, the base material 80 is test-welded under each set of conditions (step S7). After the test welding, the appearance, strength, etc. of the welded portion are evaluated, and it is determined whether these evaluation items satisfy the required specifications (step S8). If the determination result of step S8 is affirmative, i.e., the evaluation items related to the welded portion's performance satisfy the required specifications, the welding condition setting process is terminated.

[0059] On the other hand, if the determination result in step S8 is negative, that is, if the evaluation items related to the performance of the welded portion do not satisfy the predetermined required specifications, the welding operator modifies the welding current command value and / or the operating parameters of filler feed motor 25 (step S9). The modified values ​​are input from first input unit 11, replace the existing values ​​stored in memory unit 12, and are saved as a new version of a table or text file. Note that the modified values ​​that replace the existing values ​​do not need to be saved in memory unit 12. Returning to step S7, test welding of base material 80 is performed again, and the series of processes from steps S7 to S9 are repeated until the determination result in step S8 becomes positive.

[0060] Furthermore, if it is selected in step S1 that the filler 27 is not to be used, the process proceeds to step S10, as described above, and the subsequent processes are executed. The processes of steps S10 to S12 are the same as the processes of steps S2 to S4, and the processes of steps S13 to S16 are the same as the processes of steps S6 to S9. Therefore, a detailed description of the processes of steps S10 to S16 will be omitted. However, in this case, when executing step S10, it is selected not to use the filler 27 on the input screen shown in FIG. 4A.

[0061] In step S13, which corresponds to step S6, welding navigation unit 13 or first control unit 15 causes first display unit 14 to display the welding current command value calculated in step S10 and the second welding conditions. As shown in FIG. 5B , only the items of the second welding conditions that are not related to filler 27, i.e., the flow rate of the shielding gas, the electrode diameter, and the electrode tip angle θ1, are displayed on first display unit 14.

[0062] In step S16, which corresponds to step S9, the welding operator corrects the welding current command value.

[0063] In this embodiment, an example has been shown in which test welding of base material 80 and evaluation of the quality of the welded portion are performed, and the welding current command value and the like are corrected based on the evaluation results, but the execution of these steps (steps S7 to S9, S14 to S16) is not essential and may be omitted. In this case, the welding current command value and the operating parameters of filler feed motor 25 are automatically set based on the first welding conditions input in step S2. Furthermore, the welding current command value is automatically set based on the first welding conditions input in step S10.

[0064] [3: Filler Feed Mode and Filler Feed Motor Operation Parameters] Figure 6 is a diagram showing a list of operation parameters automatically set by the filler feed motor. As shown in Figure 6, there are a wide variety of operation parameters automatically set by welding navigation unit 13. First, the feed mode of filler 27 is set according to the first welding conditions input from first input unit 11. Whether or not crater treatment is to be performed is also set. Note that in the examples described below, crater treatment is set to be performed in all cases. Below, the operation parameters set according to the feed mode are described.

[0065] 7 is a time chart showing various output waveforms when the filler feed mode is the continuous feed mode. The continuous feed mode is a mode in which filler 27 is continuously fed toward base material 80 at filler feed speed FWD1 automatically set by welding navigation unit 13. In the continuous feed mode, welding current I1, filler feed speed FWD1, delay time DT1, ENDT, crater feed speed, retract feed speed REV, and retract length LEV are automatically set by welding navigation unit 13. The filler feed speed corresponds to the amount of filler 27 fed per unit time.

[0066] When torch switch 41 is pressed, a welding current (output current) is supplied from output unit 16 to electrode 43 via first power cable 61. The welding current is determined based on a welding current command value automatically set by welding navigation unit 13. In this case, current value I1 of the welding current is constant and is the same value as the welding current command value.

[0067] When a welding current detection unit (not shown) detects that a welding current is flowing through electrode 43, filler feed motor 25 starts and becomes operable. After delay time DT1 automatically set by welding navigation unit 13 has elapsed, filler feed motor 25 operates and continuously feeds filler 27 toward the base metal at filler feed speed FWD1. The operation and operation start timing for starting filler feed motor 25 are the same in the first intermittent feed mode, pulse synchronous mode, and second intermittent feed mode described below.

[0068] To stop the feed of filler 27 and end the main welding, the filler switch 28 is pressed. At this point, the welding torch 40 is fixed in the same position without moving. When the operation of the filler switch 28 detects that the state of the filler switch 28 has transitioned from the ON state to the OFF state, a detection signal is sent to the second communication unit 23 via the first communication unit 17. When this signal is detected by the second communication unit 23, the filler feed speed is changed from FWD1 to the retract feed speed REV after the delay time ENDT automatically set by the welding navigation unit 13 has elapsed. When the filler 27 is fed at the retract feed speed REV, the filler 27 is fed backward so as to move away from the base material 80. This movement of the filler 27 is sometimes referred to as a retract operation. This prevents the filler 27 from adhering to the base material 80 even if the tip of the filler 27 temporarily abuts against the welded surface of the base material 80. Furthermore, since filler 27 is fed at filler feed speed FWD1 until delay time ENDT has elapsed while welding torch 40 is kept in a fixed position, it is possible to prevent a depression from occurring at the welding end point. Note that the reverse feed period TR during which filler 27 is fed in the reverse direction at retract feed speed REV is set as shown in equation (1) using retract feed speed REV and retract length LEV that are automatically set by welding navigation unit 13.

[0069] 8 is a time chart showing various output waveforms when the filler feeding mode is the first intermittent feeding mode. The first intermittent feeding mode is a mode in which the filler 27 is fed toward the base material 80 while periodically varying the filler feeding speed.

[0070] In the first intermittent feed mode, the items automatically set by welding navigation unit 13 differ from those in the continuous feed mode in the following respects. First, two filler feed speeds, FWD1 and FWD2, are set. In addition to DT1 and ENDT, a filler feed speed rise delay time DT2 (hereinafter simply referred to as delay time DT2) and a filler feed speed fall delay time DT3 (hereinafter simply referred to as delay time DT3) are set. Furthermore, the duty and feed frequency f are additionally automatically set by welding navigation unit 13. Note that the operation of filler switch 28 to transition to crater treatment and the associated operating parameters and operating timing of filler feed motor 25 are the same as those described for the continuous feed mode.

[0071] 8, when the filler feed motor 25 starts operating at the timing described above, the filler feed motor 25 feeds the filler 27 toward the base material 80 at a filler feed speed FWD2. After a period T1 has elapsed, the filler feed speed switches from FWD2 to FWD1. After a period T has elapsed from the start of operation, the filler feed speed switches again from FWD1 to FWD2. In other words, the filler feed speed fluctuates in a cycle T, and during a cycle T1 of the cycle T, the filler feed speed is FWD2, and during the other periods, the filler feed speed is FWD1.

[0072] As is clear from these, the feeding frequency f satisfies the relationship shown in formula (2), and the duty satisfies the relationship shown in formula (3).

[0073] f=1 / T (2) Duty=T1<T (3) The delay times DT2 and DT3 described above are automatically set by welding navigation unit 13. In this way, heat can be appropriately input to base material 80 according to the material and thickness of base material 80 and the shape of the joint, thereby stabilizing the welding quality.

[0074] 9 is a time chart showing various output waveforms when the filler feed mode is the pulse synchronous mode. In the pulse synchronous mode, when the welding current is a pulse current, the filler 27 is fed toward the base material 80 while periodically varying the filler feed speed in synchronization with the pulse frequency of the pulse current.

[0075] In the pulse synchronization mode, the items automatically set by welding navigation unit 13 differ from those in the first intermittent feed mode in the following respects. First, the welding current fluctuates in a cycle Tw. In the cycle Tw, the current value of the welding current in a first period Tp is Ip, and the current value of the welding current in a second period Tb following the first period Tp is Ib (0<Ib<Ip).

[0076] The feed frequency f automatically set by the welding navigation unit 13 is the reciprocal of the period Tw and satisfies the relationship shown in equation (4).

[0077] f=1 / Tw (4) Furthermore, the duty satisfies the relationship shown in equation (5).

[0078] Duty=Tp<Tw (5) The operation of the filler switch 28 to transition to crater processing and the associated operating parameters and operating timing of the filler feed motor 25 are the same as those described in the continuous feed mode.

[0079] 9 , when filler feed motor 25 starts operating at the timing described above, filler feed motor 25 feeds filler 27 toward base material 80 at filler feed speed FWD2. When the welding current changes from first current Ip to second current Ib, the filler feed speed switches from FWD2 to FWD1. Thereafter, the filler feed speed also switches periodically from FWD2 to FWD1 and from FWD1 to FWD2 in synchronization with the pulse frequency of the welding current.

[0080] As in the first intermittent feed mode, the delay times DT2 and DT3 are automatically set by the welding navigation unit 13. In this way, it is possible to appropriately input heat to the base material 80 according to the material and thickness of the base material 80 and the shape of the joint, thereby stabilizing the welding quality.

[0081] 10 is a time chart showing various output waveforms when the filler feeding mode is the second intermittent feeding mode. The second intermittent feeding mode is a mode in which the filler feeding speed is changed by operating the filler switch 28, and the filler 27 is fed toward the base material 80.

[0082] In the second intermittent feed mode, the operation of the filler feed motor 25 differs from that in the first intermittent feed mode in the following respects.

[0083] 10 , after detecting the start of welding current flow, filler switch 28 is pressed to set the operation state of filler switch 28 to the ON state. Upon detecting this state, filler feed motor 25 feeds filler 27 toward base material 80 at filler feed speed FWD2. If filler switch 28 continues to be pressed in this state, the filler feed speed is maintained at FWD2. Next, if filler switch 28 is released to set the operation state to the OFF state, filler feed motor 25 detects this state and switches the filler feed speed from FWD2 to FWD1 to feed filler 27 toward base material 80. As described above, FWD1 and FWD2 are automatically set by welding navigation unit 13.

[0084] Thereafter, the filler feed speed changes when the filler switch 28 is pressed or released, but this only applies when the time period during which the filler switch 28 is pressed, for example, the time Ta or the time Tb shown in FIG. 10, is 0.2 seconds or longer.

[0085] If the time period during which the filler switch 28 is pressed, for example, the time Tc shown in Fig. 10, is less than 0.2 seconds, and the filler switch 28 is released to turn the operation state OFF, the filler feed motor 25 switches the filler feed speed from FWD2 to the retract feed speed REV. In other words, the filler 27 is fed in reverse away from the base material 80, and the process shifts to crater processing.

[0086] In this embodiment, filler supply device 20 is operated starting from the detection of the welding current. However, the welding period may be divided into an initial welding period and a main welding period, and filler supply device 20 may be operated based on the operating parameters automatically set by welding navigation unit 13 starting from the transition point to the main welding period.

[0087] [4: Effects, etc.] As described above, arc welding apparatus 70 according to this embodiment includes at least welding power source 10, welding torch 40 connected to welding power source 10, electrode 43 held by welding torch 40, and filler supply device 20 that supplies filler 27 toward the welding point of base material 80.

[0088] Welding power source 10 has at least first input unit 11 , memory unit 12 , welding navigation unit 13 , first display unit 14 , first control unit 15 , output unit 16 , and first communication unit 17 .

[0089] Storage unit 12 temporarily stores the first welding conditions input from first input unit 11. Note that storage unit 12 may store the first welding conditions for a certain period of time.

[0090] When filler 27 is not used in TIG welding, welding navigation unit 13 calculates the welding current command value according to at least the material and thickness of base material 80, which are among the first welding conditions. When filler 27 is used, welding navigation unit 13 also calculates the operating parameters of filler supply device 20, and more specifically, filler feed motor 25. In either calculation, the shape of the joint is taken into consideration as necessary.

[0091] First display unit 14 displays the calculation results of welding navigation unit 13. First display unit 14 also displays information other than the calculation results, such as the second welding conditions described above.

[0092] First control unit 15 controls output unit 16 based on the welding current command value. Furthermore, when the welding current is set to a pulse current in the pulse setting of the first welding conditions, first control unit 15 controls output unit 16 based on the setting.

[0093] The output unit 16 outputs a welding current to the electrode 43 based on the current control command output from the first control unit 15. The first communication unit 17 transmits the filler feed control command output from the first control unit 15 to the filler supply device 20.

[0094] The filler supply device 20 has at least a motor controller 21 and a filler feed motor 25 , and the motor controller 21 has a second control unit 22 and a second communication unit 23 .

[0095] The second control unit 22 controls the operation of the filler feed motor 25 based on at least the filler feed control command. The second communication unit 23 receives the filler feed control command transmitted from the first communication unit 17. The filler feed motor 25 feeds the filler 27 based on the motor control command output from the second control unit 22.

[0096] The current control command output from the first control unit 15 includes at least a welding current command value. The filler feed control command output from the first control unit 15 includes at least some of the above-mentioned operating parameters.

[0097] According to this embodiment, the welding operator can set the material and thickness of the base material 80, thereby calculating an optimal welding current command value.

[0098] As described above, in TIG filler welding, it is necessary to independently set the feed rate of the filler 27, i.e., the filler feed rate, separately from the welding current. However, it has been difficult for a welding operator who is not familiar with welding techniques and welding operations, i.e., a beginner at welding, to set an appropriate filler feed rate.

[0099] On the other hand, according to this embodiment, when filler 27 is used, it is possible to automatically calculate the operating parameters of filler feed motor 25, including the filler feed speed. This allows even a beginner to properly perform TIG welding, thereby stabilizing the welding quality.

[0100] The operating parameters also include at least one of the filler feed speed, the filler 27 feed frequency f, and whether or not crater processing is performed. If crater processing is performed, the operating parameters include the crater feed speed, the retract feed speed REV, and the retract length LEV.

[0101] The crater feed speed is the filler feed speed during crater processing. The retract feed speed REV is the filler feed speed during a retraction operation in which the filler 27 is pulled up so as to separate from the base material 80. The retract length LEV is the length by which the filler 27 is pulled up during the retraction operation.

[0102] In addition, the first welding conditions include a pulse setting that determines whether the welding current is a pulse current, and the operating parameters include a feed mode of the filler 27 that corresponds to the material, plate thickness, and pulse setting of the base material 80.

[0103] By setting the operating parameters in this manner, the feed mode of the filler 27 can be appropriately set in TIG filler welding according to the material, thickness, and shape of the base material 80, and the filler 27 can be appropriately fed in each mode.

[0104] The welding navigation unit 13 is configured to select the second welding conditions as the recommended conditions for welding, and to display the second welding conditions on the first display unit 14 .

[0105] When filler 27 is not used, the second welding conditions include at least the electrode diameter, which is the diameter of electrode 43, the electrode tip angle θ1, which is the angle of the tip of electrode 43, and the gas flow rate, which is the flow rate of the shielding gas for protecting the welded point.

[0106] When filler 27 is used, the second welding condition further includes filler insertion angle θ2, electrode-base metal distance, and filler diameter, which is the diameter of filler 27. Filler insertion angle θ2 is the angle between the surface to be welded of base metal 80 and the feed direction of filler 27. The electrode-base metal distance is the distance between the surface to be welded of base metal 80 and the tip of electrode 43.

[0107] By setting the recommended welding conditions in advance in this way, there is no need to individually set up peripherals other than the welding power source 10 and filler supply device 20, and even beginners can perform TIG welding or TIG filler welding appropriately.

[0108] Welding navigation unit 13 is preferably configured to display at least the welding current command value and the second welding condition on first display unit 14 when the first welding condition is input from first input unit 11. When filler 27 is used, welding navigation unit 13 is more preferably configured to display the welding current command value, operating parameters of filler feed motor 25, and the second welding condition on first display unit 14.

[0109] This allows welding operators, including beginners, to check various welding conditions at a glance. If the displayed values ​​are inappropriate, they can review the input conditions or correct the displayed values ​​as appropriate. This prevents TIG welding from being performed under inappropriate conditions.

[0110] The communication format between the first communication unit 17 and the second communication unit 23 is digital communication. Data is transmitted and received between the first communication unit 17 and the second communication unit 23 via wired or wireless communication.

[0111] In this manner, various numerical values ​​calculated by welding navigation unit 13 can be reliably transmitted to second control unit 22 of motor controller 21. This makes it possible to reliably cause filler feed motor 25 to perform a desired operation based on the filler feed control command output from first control unit 15.

[0112] The arc welding device 70 may further include a remote controller 30 having a second input unit 31 , a second display unit 32 , and a third communication unit 33 .

[0113] Second input unit 31 is configured to allow input of the first welding conditions. Second display unit 32 displays the calculation results of welding navigation unit 13. Second display unit 32 also displays the second welding conditions.

[0114] Third communication unit 33 transmits the first welding conditions input from second input unit 31 to first communication unit 17. First communication unit 17 transmits the first welding conditions transmitted from third communication unit 33 to at least one of memory unit 12 and welding navigation unit 13 of welding power source 10.

[0115] By providing the remote controller 30 in this manner, even when the welding power source 10 and the base material 80 are separated, the welding operator preparing for welding the base material 80 can easily input the first welding conditions.

[0116] The communication format between the first communication unit 17 and the third communication unit 33 is digital communication. Data is transmitted and received between the first communication unit 17 and the third communication unit 33 via wired or wireless communication.

[0117] In this way, the numerical values ​​relating to the first welding conditions input by operating remote controller 30 can be reliably transmitted to welding power source 10 .

[0118] In addition, if the period during which the base material 80 is TIG welded without using the filler 27 is long, the first control cable 63 and the filler supply device 20 can be omitted from the arc welding device 70 of this embodiment.

[0119] The welding condition setting method according to this embodiment includes at least the following steps.

[0120] In the first step (steps S1, S2, and S10 in FIG. 3), it is selected whether or not to use the filler 27.

[0121] In the second step (steps S2 and S10 in FIG. 3), the material and thickness of the base material 80 and whether or not the welding current is a pulse current are set.

[0122] In the third step (steps S3 and S11 in FIG. 3), at least the welding current command value is automatically set in accordance with the settings made in the second step.

[0123] If it is selected in the first step to use the filler 27, in the fourth step (step S3 in FIG. 3), the operating parameters of the filler feed motor 25 are automatically set in accordance with the settings made in the second step.

[0124] In this way, the welding operator can calculate an optimal welding current command value by setting the material and thickness of the base material 80. Furthermore, when filler 27 is used, the operating parameters of filler feed motor 25, including the filler feed speed, can be automatically calculated. This allows even beginners to properly perform TIG welding, and stabilizes the welding quality.

[0125] If the welding current command value calculated in the third step does not satisfy the required specifications for arc welding, it is preferable to modify the welding current command value in the fifth step (steps S9 and S16 in FIG. 3) so that the required specifications are satisfied.

[0126] Even if the welding current command value calculated by the welding navigation unit 13 is actually inappropriate, by being able to correct the command value, TIG welding or TIG filler welding can be performed appropriately, thereby preventing the occurrence of welding defects and stabilizing welding quality.

[0127] If the operating parameters calculated in the fourth step do not satisfy the required specifications for arc welding, it is preferable to modify the operating parameters in a sixth step (step S9 in FIG. 3) so that the required specifications are satisfied.

[0128] Even if the operating parameters calculated by the welding navigation unit 13 are actually inappropriate, by making it possible to correct the operating parameters, TIG filler welding can be performed appropriately, the occurrence of welding defects can be prevented, and the welding quality can be stabilized.

[0129] Other Embodiments In the present specification, an example has been shown in which the filler supply device 20 is provided with the filler switch 28, and the operation of the filler feed motor 25 is stopped by operating the filler switch. However, the present invention is not particularly limited to this, and for example, the filler switch 28 may be omitted, and the function of the filler switch 28 may be incorporated into the torch switch 41.

[0130] In steps 5 and 6, if the results of the actual test welding do not satisfy the required specifications for arc welding even after the welding current command value and the operating parameters are modified, the second welding conditions are modified. However, as described above, when modifying the second welding conditions, it is not enough to simply modify the numerical values; the welding operator himself must adjust each part of the arc welding device 70.

[0131] The arc welding device disclosed herein is useful because it can automatically set an appropriate welding current specification value, filler feed amount, or both, allowing even welding operators with insufficient knowledge or experience to perform welding work appropriately.

[0132] REFERENCE SIGNS LIST 10 Welding power source 11 First input unit 12 Memory unit 13 Welding navigation unit 14 First display unit 15 First control unit 16 Output unit 17 First communication unit 20 Filler supply device 21 Motor controller 22 Second control unit 23 Second communication unit 24 Filler storage unit 25 Filler feed motor 26 Filler guide 27 Filler 28 Filler switch 30 Remote controller 31 Second input unit 32 Second display unit 33 Third communication unit 40 Welding torch 41 Torch switch 42 Guide holder 43 Electrode 50 Gas cylinder 60 Composite cable 61 First power cable 62 Second power cable 63 First control cable 64 Second control cable 65 Gas piping 70 Arc welding device 80 Base material 81 First sheet material 82 Second sheet material

Claims

1. A welding power source comprising at least: a welding torch connected to the welding power source; an electrode held by the welding torch; and a filler supply device that supplies filler toward a welding point on a base metal; wherein the welding power source has at least a first input unit, a memory unit, a welding navigation unit, a first display unit, a first control unit, an output unit, and a first communication unit; wherein the memory unit at least temporarily stores first welding conditions input from the first input unit; wherein the welding navigation unit, when not using the filler, calculates a welding current command value in accordance with at least the material and thickness of the base metal among the first welding conditions; and when using the filler, calculates the welding current command value in accordance with at least the material and thickness of the base metal and calculates operating parameters of the filler supply device; the first display unit at least displays the calculation result of the welding navigation unit; the first control unit controls the output unit based on at least the welding current command value; and the output unit outputs a welding current to the electrode based on a current control command output from the first control unit; the first communication unit transmits a filler feed control command output from the first control unit to the filler supply device; the filler supply device has at least a second control unit, a second communication unit, and a filler feed motor; the second control unit controls operation of the filler feed motor based on at least the filler feed control command; the second communication unit receives the filler feed control command transmitted from the first communication unit; the filler feed motor feeds the filler based on a motor control command output from the second control unit; the current control command includes at least the welding current command value; and the filler feed control command includes at least a portion of the operating parameters.

2. An arc welding apparatus as defined in claim 1, wherein the operating parameters include at least one of the filler feed speed, the filler feed frequency, and whether or not crater treatment is performed, and when crater treatment is performed, the operating parameters further include a crater feed speed, which is the filler feed speed during crater treatment, a retract feed speed, which is the filler feed speed during a retract operation that pulls the filler up so that it is away from the base metal, and a retract length, which is the length by which the filler is pulled up during the retract operation.

3. An arc welding device according to claim 2, wherein the first welding conditions include a pulse setting that determines whether the welding current is a pulse current, and the operating parameters include a feed mode of the filler metal that corresponds to the thickness and material of the base metal and the pulse setting.

4. An arc welding device according to claim 1, wherein the welding navigation unit is configured to select second welding conditions as recommended conditions for welding and to display the second welding conditions on the first display unit, and wherein, when the filler is not used, the second welding conditions include at least an electrode diameter which is the diameter of the electrode, an electrode tip angle which is the angle of the tip of the electrode, and a gas flow rate which is the flow rate of shielding gas that protects the welding point, and, when the filler is used, the second welding conditions further include a filler insertion angle which is the angle between the welded surface of the base metal and the feed direction of the filler, an electrode-base metal distance which is the distance between the welded surface of the base metal and the tip of the electrode, and a filler diameter which is the diameter of the filler.

5. An arc welding device according to claim 4, characterized in that when the first welding condition is input from the first input unit, the welding navigation unit is configured to cause the first display unit to display at least the welding current command value and the second welding condition.

6. An arc welding device according to claim 1, characterized in that the communication format between the first communication unit and the second communication unit is digital communication, and data transmission and reception between the first communication unit and the second communication unit is performed by wired communication or wireless communication.

7. An arc welding device according to claim 1, further comprising a remote controller having a second input unit, a second display unit, and a third communication unit, wherein the second input unit is configured to be able to input the first welding conditions, the second display unit is configured to be able to at least display the calculation results of the welding navigation unit, the third communication unit transmits the first welding conditions input from the second input unit to the first communication unit, and the first communication unit transmits the first welding conditions transmitted from the third communication unit to at least one of the memory unit and the welding navigation unit.

8. An arc welding device according to claim 7, characterized in that the communication format between the first communication unit and the third communication unit is digital communication, and data transmission and reception between the first communication unit and the third communication unit is performed by wired communication or wireless communication.

9. A method for setting welding conditions in an arc welding apparatus as claimed in any one of claims 1 to 8, comprising at least a first step of selecting whether or not to use the filler, a second step of setting the material and thickness of the base metal and whether or not the welding current is a pulse current, and a third step of automatically setting at least the welding current command value in accordance with the settings in the second step, and if it is selected in the first step that the filler is to be used, further comprising a fourth step of automatically setting the operating parameters in accordance with the settings in the second step.

10. A welding condition setting method according to claim 9, further comprising a fifth step of correcting the welding current command value so as to satisfy the required specifications for arc welding if the welding current command value calculated in the third step does not satisfy the required specifications for arc welding.

11. A welding condition setting method as claimed in claim 9, further comprising a sixth step of correcting the operating parameters so as to satisfy the required specifications for arc welding if the operating parameters calculated in the fourth step do not satisfy the required specifications for arc welding.

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