JP4864232B2 - Consumable two-electrode arc welding end method, welding end control method, and welding robot - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to improvement of a method for terminating arc welding in which two consumable electrodes (hereinafter referred to as wires) are fed and welded in one torch in consumable electrode arc welding.
[0002]
[Prior art]
In the construction of various welded structures, thin plate high-speed welding or thick plate high-weld welding is performed to improve work efficiency. To further improve the efficiency, as shown in FIG. A consumable electrode arc welding method of a two-electrode, one-torch system that feeds a wire is employed. In the figure, the leading wire tip 3a is supplied from a welding power source (not shown) between the leading tip 1 and the trailing tip 2 and the workpiece 8 and fed from the leading tip 1 and the trailing tip 2, respectively. And arcs 5 and 6 are generated from the trailing wire tip 4a, respectively. The nozzle 10 surrounds the leading tip 1 and the trailing tip 2 and supplies a shielding gas 11 to the inside of the nozzle 10.
[0003]
In FIG. 2, the molten metal in the molten pool 7 formed by the arc 5 generated from the preceding wire 3 tries to flow backward due to surface tension, but the arc force generated from the trailing wire 4 is The molten metal that is going to flow backward is pushed back directly under the arc 5 generated from the preceding wire 3 to make the amount of molten metal uniform at each welding position.
[0004]
FIG. 3 is a diagram showing a general configuration of the above-described two-electrode one-torch type welding robot. In the figure, a welding torch 14 having a leading tip 1 and a trailing tip 2 is attached to the tip of a manipulator 21, and a leading wire welding power supply device 23 to be supplied to the leading tip 1 and a trailing wire to be supplied to the trailing tip 2. The welding power supply device 24 supplies welding power between the leading tip 1 and the trailing tip 2 and the workpiece 8. The leading wire feeding device 25 and the trailing wire feeding device 26 feed the wires to the leading chip 1 and the trailing chip 2, respectively. The robot control device 27 controls the manipulator 21, the preceding wire welding power source device 23, and the subsequent wire welding power source device 24.
When the welding direction is changed, the leading and trailing are interchanged. Therefore, the leading tip 1, the leading wire 3, the leading wire feeding device 25, the leading wire welding power supply device 23, the trailing tip 2, the trailing wire 4, and the trailing The preceding and following descriptions of the respective reference numerals of the row wire feeding device 26 and the subsequent wire welding power source device 24 are interchanged.
[0005]
[Prior art 1]
A welding end method (hereinafter, referred to as “prior art 1”) using a conventionally proposed two-electrode, one-torch welding robot will be described with reference to FIGS. 4 and 5. In order to simplify the explanation, it is assumed that the leading wire 3 and the trailing wire 4 are fed. FIG. 4 is a diagram for explaining a method for ending the two-electrode one-torch type consumable electrode arc welding according to Prior Art 1, and FIG. It is a figure explaining the termination method.
[0006]
FIG. 4 (A) shows a state during consumable electrode arc welding of the two-electrode one-torch method. In the figure, the leading wire 3 and the trailing wire 4 protrude from the nozzle 10, and the leading wire 3 and the trailing wire 4 and the covering wire 4 are connected to the leading wire welding power source 23 and the trailing wire welding power source 24 shown in FIG. Electric power is supplied between the welding object 8 and arcs 5 and 6 are generated from the leading wire tip 3a and the trailing wire tip 4a, respectively, and a weld bead 9 is formed.
[0007]
Then, as shown in FIG. 4B, when the leading wire tip 3a reaches the welding end position P2, which is the terminal portion of the weld bead formed by the leading wire 3, the robot controller 27 shown in FIG. It is determined that the leading wire tip 3a has reached the welding end position P2, and a crater processing command signal is output to the leading wire welding power source device 23 and the trailing wire welding power source device 24.
[0008]
Here, the crater process will be described. At the weld bead end portion, a so-called crater is formed in the molten pool immediately under the arc, which is depressed by the arc force. This crater is likely to have defects such as cracks and shrinkage holes. In order to prevent this, the operation of reducing or eliminating the crater is called crater processing. In general, a method of decreasing the welding current continuously or stepwise at the end portion of the weld bead, or interrupting the welding current is used.
In addition, let said crater process of said prior art be 2nd crater process in this invention.
[0009]
Thereafter, when the crater process is finished, the robot control device 27 shown in FIG. 3 inputs a welding end command signal to the preceding wire welding power source device 23 and the subsequent wire welding power source device 24, and FIG. ) Finish the welding as shown in FIG.
[0010]
FIG. 5 is a diagram showing an appearance of a weld bead end portion according to a consumable electrode arc welding end method of the two-electrode one-torch method of the prior art 1. As shown in the figure, since both the preceding wire 3 and the succeeding wire 4 perform crater processing, two crater processing traces 15 and 16 are generated. Therefore, not only the appearance of the weld bead is deteriorated, but a recess 15a is generated between the two crater processing traces, and the weld joint strength is weakened. In addition, when performing high-speed welding, the depressed molten pool before the crater treatment is solidified without being cratered and becomes a molten pool trace 13, so that defects such as cracks and shrinkage holes are likely to occur.
[0011]
[Prior Art 2]
In order to solve the above-mentioned problems, Japanese Patent Application Laid-Open No. 2001-113373 “Control Method of Tandem Arc Welding” (hereinafter referred to as Prior Art 2) has been proposed.
FIG. 6 is a diagram illustrating an apparatus for performing tandem arc welding according to Conventional Technique 2. In the figure, a leading wire welding power source device 44 and a trailing wire welding power source device 45 supply power between a leading tip 41 and a trailing tip 42 and a workpiece 43, respectively. The leading wire feeding device 46 and the trailing wire feeding device 47 supply the leading wire 48 and the trailing wire 49 to the leading tip 41 and the trailing tip 42, respectively, and generate an arc 50 and an arc 51. A molten pool 52 is formed by the arc 50 and the arc 51, and a weld bead 53 is formed behind the molten pool 52. The welding control device 54 performs operation control of the welding robot 55 and output control of the power supply device 44 for leading wire welding and the power supply device 45 for subsequent wire welding.
[0012]
FIG. 7 is a time chart for explaining a control method at the end of welding according to the prior art 2. FIG. 7 (A) shows the elapsed time t of the preceding wire energization current, and FIG. 7 (B) shows the preceding wire applied voltage. (C) shows the time t of the moving speed of the leading tip 41 and the trailing tip 42, and (D) shows the time t of the trailing wire energization current. FIG. 4E shows the passage of time t of the trailing wire applied voltage.
[0013]
When the leading tip 41 reaches the welding end position P2 at time t1 shown in FIG. 7, the energizing current of the leading wire 48 is decreased from I1 to I2 as shown in FIG. As shown in B), the applied voltage of the leading wire 48 is decreased from E1 to E2.
Thereafter, after the waiting time Td1 has elapsed, the arc of the preceding wire 48 is stopped and the molten pool is reduced.
[0014]
When the succeeding tip 42 reaches the welding end position P2 at time t2 in the figure, the movement of the leading tip 41 and the succeeding tip 42 is stopped as shown in FIG. Then, as shown in FIG. 4D, the energization current of the trailing wire 49 is decreased from I3 to I4, and as shown in FIG. 4E, the applied voltage of the trailing wire 42 is changed from E3 to E4. Reduce to.
Thereafter, the arc of the trailing wire 49 is stopped after the waiting time Td2 has elapsed.
[0015]
The energizing currents I2 and I4 reduced before the arc is stopped are appropriately about half of the normal welding currents I1 and I2, respectively. Further, the applied voltages E2 and E4 reduced before stopping the arc may be set to values suitable for the reduced energization currents I2 and I4, respectively.
[0016]
Thus, by reducing the current applied to the preceding wire 48 and the succeeding wire 49 and the voltage to be applied at the end of welding and stopping after the waiting time, it is possible not only to prevent the molten metal from scattering and to stabilize the molten pool. Although it has been disclosed that it is possible to obtain a good weld end portion having no welding defects such as unevenness, pits and cracks, it has the following problems.
[0017]
[Problems to be solved by the invention]
In the prior art 2 described above, as shown in FIG. 7, after reducing the current and voltage applied to the leading wire 48, welding is performed only by the trailing wire 49. The welding speed at this time is a speed at which high-speed welding is performed, as shown in FIG. Therefore, after reducing the current and voltage applied to the leading wire 48, the moving speed of the leading tip 41 and the trailing tip 42 is too fast to perform welding only with the arc of the trailing wire 49, so that the weld bead width In some cases, the weld bead near the welding end position cannot be obtained with a beautiful appearance.
Further, in high-speed welding in which the welding speed exceeds 2 [m / min], in order to obtain a uniform weld bead, the ratio of the current applied to the preceding wire 48 and the current applied to the subsequent wire 49 is 2: 1. Degree. Accordingly, if the current applied to the preceding wire 48 is reduced and stopped while maintaining the high-speed welding speed, the current ratio applied to the preceding wire 48 and the succeeding wire 49 is not an appropriate ratio, and high-speed welding is performed. In this case, the arc force of the trailing wire 49 becomes excessive, the arc force blows off the molten pool, the weld bead becomes non-uniform, and a welding defect occurs.
[0018]
[Means for Solving the Problems]
The invention described in claim 1 at the time of filing is an invention in the case where the trailing wire 4 of the first embodiment shown in FIGS. 8 and 9 performs the first and second crater processing, and two wires are included in one torch. In a consumable two-electrode arc welding end method for feeding and welding a wire, the feeding and energization of the preceding wire 3 is stopped at the welding end position P2, and the welding torch is slower than the normal welding speed in the welding direction. The consumable two-electrode arc welding end method in which the trailing wire 4 performs the first crater processing while moving the first crater processing distance D1 and then stops the movement of the welding torch and the trailing wire performs the second crater processing. It is.
[0019]
The invention according to claim 2 at the time of filing is a consumable two-electrode arc welding end method in which the first crater processing distance D1 according to claim 1 at the time of filing is “the distance between the wire tips of the standard protruding length” L2. is there.
[0020]
The invention according to claim 3 at the time of filing is the end of consumable two-electrode arc welding in which the first crater processing distance D1 according to claim 1 at the time of filing is calculated from the first crater processing moving speed and the first crater processing moving time. Is the method.
[0021]
In the invention according to claim 4 at the time of filing, the feeding and energization of the preceding wire 3 are stopped at the welding end position P2 of the embodiment 2 shown in FIG. A welding end method,
In a consumable two-electrode arc welding end method in which two wires are fed and welded in one torch,
When the leading tip 1 reaches the welding end position P2, the feeding and energization of the leading wire 3 are stopped, and the first crater processing speed is lower than the normal welding speed while moving the welding torch in the welding direction. The trailing wire 4 performs the first crater processing with the crater processing current value and the first crater processing voltage value,
Next, when the trailing wire 4 reaches the second crater processing position P4, the welding torch is stopped, and the second crater processing is started and predetermined by the second crater processing current value and the second crater processing voltage value. This is a consumable two-electrode arc welding end method that starts measuring the second crater processing time and ends the second crater processing when the measurement of the second crater processing time is completed.
[0022]
The invention described in claim 5 at the time of filing is an invention obtained by adding anti-stick treatment and welding release treatment to the invention described in claim 4 at the time of filing, as shown in FIGS. 10 and 15 of the second embodiment. In addition, it is a welding end control method in which the feeding and energization of the preceding wire 3 are stopped and the succeeding wire 4 performs the first and second crater processing,
In a consumable two-electrode arc welding end control method for feeding and welding two wires in one torch,
When the preceding wire 3 has reached the welding end position P2, that is, when the trailing wire 4 has reached the first crater processing start position P3, the “first crater processing start position welding torch is commanded to end the welding of the preceding wire. "Moving step" (corresponding to step ST9),
A “first crater processing command step” (corresponding to step ST10) for giving a command for performing the first crater processing at a first crater processing speed at which the subsequent wire is slower than the normal welding speed;
When the preceding wire welding end process command is input, the anti-stick process and the welding release process of the preceding wire 3 are performed, and after the anti-stick process and the welding release process are completed, it is determined that the preceding wire 3 is not welded. A "preceding wire welding end processing step" (corresponding to step ST11) for processing the preceding wire welding end;
A “first crater processing step” (corresponding to step ST12) that outputs a predetermined first crater processing current value and a first crater processing voltage value when the first crater processing is commanded;
The “second crater processing start step” (step ST13) in which the welding torch is stopped when the trailing chip 2 reaches the second crater processing position P4, and the subsequent wire issues a command for performing the second crater processing. Equivalent)
When the trailing wire 4 is instructed to perform the second crater process, the second crater process current value and the second crater process voltage value are output, and measurement of a predetermined second crater process time is started. “Second crater processing step” (corresponding to step ST14) that ends the second crater processing when the measurement of the second crater processing time is completed, and the trailing wire 4 when the measurement of the second crater processing time is completed. When the anti-stick process and the welding release process are completed and it is determined that the succeeding wire 4 is not welded after the anti-stick process and the welding release process are completed, the subsequent wire welding end process is completed. This is a consumable two-electrode arc welding end control method comprising “step” (corresponding to step ST15).
[0030]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram that best represents the features of the invention according to the present application. Since it is the same as FIG. 8 described later, the description will be described later with reference to FIG.
An embodiment of the invention is a welding robot according to claim 12 at the time of filing, wherein the welding robot feeds and welds two wires in one torch, and each welding section of the work piece 8 is welded. A work program file output circuit 29 that stores predetermined {circle around (1)} welding start parameters and {circle around (2)} welding end parameters, a predetermined “standard protruding length of the preceding wire 3 or the succeeding wire 4” L1, and The electrode parameter output circuit 31 storing the electrode parameter consisting of the “standard protrusion length wire tip distance” L2 and the output signal of the work program file output circuit 29 are input, and welding is started from the welding start position. Each joint angle of the manipulator 21 for moving the welding torch to the end position is calculated (to a servo control circuit 33 described later) and the calculated value of each joint angle is calculated. (2) When the welding torch reaches the welding start position, a preceding wire welding start command signal S1 is output (to a preceding wire welding condition output circuit 35 described later), and a subsequent wire welding start command signal S2 is output. (To a later wire welding condition output circuit 36 to be described later), to output a normal welding speed (to a servo control circuit 33 to be described later), and (3) the succeeding tip 2 reaches the first crater processing start position P3. When this is done, the preceding wire welding end processing command signal S5 is output (to a preceding wire welding condition output circuit 35 described later), and the first crater processing command signal S6 is output (to a following wire welding condition output circuit 36 described later). Then, the first crater processing speed slower than the normal welding speed is output (to a servo control circuit 33 described later), and when the succeeding chip 2 reaches the second crater processing position P4, the second crater processing speed is output. And a manipulator 21 for moving the welding torch from the welding torch moving path calculation circuit 32 (1) (to a subsequent wire welding condition output circuit 36 described later). The calculated values of the joint angles are controlled to control the manipulator 21. (2) When the succeeding chip 2 reaches the second crater processing position P4, the servo control circuit 33 stops the manipulator 21, and (1) When the preceding wire welding start command signal S1 is input, the welding current value and the welding voltage value supplied to the preceding wire 3 at the welding start position are output (to the preceding wire welding power supply device 23 described later), (2) When the arc 5 is generated at the leading wire tip 3a, a leading wire welding start completion signal S3 is output to the welding torch movement path calculation circuit 32, and (3) leading When the wire welding end processing command signal S5 is input, a signal for instructing anti-stick processing and welding release processing of the preceding wire 3 is output (to a power device 23 for leading wire welding described later), and it is determined that there is no welding. In some cases, the preceding wire welding condition output circuit 35 outputs a preceding wire welding end processing completion signal S7 to the welding torch moving path calculation circuit 32, and a signal that commands the energization of the welding current of the preceding wire from the preceding wire welding condition output circuit 35. Is input to the preceding wire 3 when the command is input, and when the command signal for the antistic processing and welding release processing of the preceding wire 3 is input, the leading wire 3 performs antistic processing and welding release processing. When the power supply device 23 for wire welding and (1) the trailing wire welding start command signal S2 are input, the trailing wire at the welding start position When the arc 6 is generated at the trailing wire tip 4a, the welding current value and the welding voltage value supplied to 4 are output (to the power supply device 24 for the following wire welding described later). The start completion signal S4 is output to the welding torch movement path calculation circuit 32, and (3) when the first crater processing command signal S6 is input, the first crater processing current value and the first crater processing voltage value (described later). When the second crater processing command signal S8 is input (4), the second crater processing current value and the second crater processing voltage value are output (to the subsequent wire welding power supply device 24) (following wire welding described later). Output to the power supply device 24), start measuring the predetermined second crater processing time, and (5) when the measurement of the second crater processing time expires, anti-stick processing and welding release of the trailing wire 4 Processing A command signal is output (to a power supply device 24 for the subsequent wire welding described later), and when it is determined that there is no welding, a subsequent wire welding end processing completion signal S9 is output to the welding torch movement path calculation circuit 32. When the wire welding condition output circuit 36 and a signal for commanding energization of the welding current of the succeeding wire are input from the succeeding wire welding condition output circuit 36, the welding current is energized to the succeeding wire 4. This is a welding robot provided with a power supply device 24 for subsequent wire welding that performs anti-stick processing and welding release processing of the trailing wire 4 when a command signal for performing anti-stick processing and welding release processing is input.
[0031]
【Example】
Hereinafter, the welding end method will be described in the first embodiment, and then the welding end control method and the welding robot by the robot controller 27 in the second embodiment will be described.
[Example 1]
FIG. 8 is a diagram for explaining Example 1 in which the preceding wire 3 and the trailing wire 4 are fed and the trailing wire 4 performs the first and second crater processes in the consumable two-electrode arc welding end method of the present invention. It is. FIG. 4A shows a state during two-electrode one-torch type consumable electrode arc welding, and the same functions as shown in FIG.
[0032]
As shown in FIG. 8B, when the leading wire tip 3a reaches the welding end position P2, the robot controller 27 shown in FIG. 3 confirms that the leading wire tip 3a has reached the welding end position P2. , The welding end command signal is output to the preceding wire welding power source device 23, and the first crater processing command signal is output to the following wire welding power source device 24. L2 shown in FIG. 8B is the distance between the wire tips of the standard protruding length, and can be used as a first crater processing distance D1 described later.
Thereafter, as shown in FIG. 5C, the trailing wire 4 performs the first crater process while moving the welding torch by the first crater processing distance D1 in the welding direction.
[0033]
Here, the first crater process is to stop the feeding and energization of the preceding wire 3, perform the welding end process while energizing only the succeeding wire 4 and moving the welding torch in the welding direction. The welding current value, welding voltage value, and welding speed during the first crater treatment period can be arbitrarily set. Usually, the welding current value and welding voltage for welding (hereinafter referred to as normal welding) until the welding torch reaches the welding end position. The value is lower than the welding speed.
[0034]
FIG. 9 is a diagram illustrating a welding end method subsequent to FIG. 8 in the welding end method of the first embodiment. 9A to 9C subsequent to FIG. 8C will be described. When the welding torch finishes moving the first crater processing distance D1, for example, the distance L2 between the wire tips, the welding torch stops, and the robot controller 27 shown in FIG. The second crater processing command signal is output, and the trailing wire 4 performs the second crater processing as shown in FIG.
Here, the second crater process is to process the crater in a state where the succeeding wire stops the welding torch, and the welding current value and the welding voltage value can be arbitrarily set. This corresponds to the crater processing described in Related Art 1.
[0035]
When the succeeding wire 4 finishes the second crater process, the robot control device 27 shown in FIG. 3 outputs a welding end command signal to the succeeding wire welding power supply device 24, and FIG. Finish welding as shown.
[0036]
As described above, in the first embodiment, only the trailing wire 4 performs the crater processing described in the related art 1 in the second crater processing, so that only one crater processing trace 15 exists as shown in FIG. Does not occur. In addition, since the moving speed of the welding torch during the first crater process shown in FIG. 8C is decelerated from the normal welding speed, the molten metal generated while moving the trailing wire 4 is caused by the arc force. Since this molten metal can be filled backward in the molten pool depressed by the arc force of the trailing wire 4, the molten pool trace 13 shown in FIG. 5 is not generated, and the appearance of the weld bead is good. It is.
[0037]
In the above-described embodiment, the first crater processing distance D1 can be set to “the distance between the wire tips of the standard protruding length” L2. Further, the first crater processing distance D1 can be calculated from the first crater processing moving speed and the first crater processing moving time. Further, the first crater processing distance D1 can be calculated as a percentage of the “standard protrusion length distance between the wire tips” L2.
[0038]
[Explanation of FIG. 10]
FIG. 10 is a view for explaining the moving distance of the welding torch from the welding start position P1 to the first crater processing start position and the second crater processing position when the trailing wire 4 of the present invention performs crater processing. .
FIG. 10 is a view for explaining the moving distance of the welding torch when the succeeding wire 4 performs crater processing in FIG. 10. The total welding torch movement distance L3, which is the distance from the welding bead formed by the preceding wire 3 to the “welding end position” P2, which is the terminal end of the welding bead, is calculated. The distance between the tips “L2” is subtracted to calculate the welding torch moving distance L4 = L3−L2 of normal welding, which is the distance from the welding start position to the first crater processing start position P3. Then, the welding torch is moved at a normal welding speed from the welding start position P1 to the first crater processing start position P3. Next, the welding torch is moved at the first crater processing speed to the second crater processing position P4 where the position of the trailing chip 2 is moved from the first crater processing start position P3 by the first crater processing distance D1. . As shown in the figure, when the preceding wire 3 reaches the “welding end position” P2, the trailing wire 4 reaches the first crater processing start position P3 at the same time.
[0039]
The welding end method of Example 1 is a welding end method in which the feeding and energization of the preceding wire 3 are stopped and the trailing wire 4 performs the first and second crater processing, as shown in FIG. When the leading tip 1 reaches the welding end position P2, the feeding and energization of the leading wire 3 are stopped, and the first crater processing current value and the first one at the first crater processing speed while moving the welding torch in the welding direction. The trailing wire 4 performs the first crater processing at the crater processing voltage value, and then stops the welding torch when the trailing wire 4 reaches the second crater processing position P4, and the second crater processing current value and Based on the second crater processing voltage value, the second crater processing is started and the measurement of the second crater processing time is started. When the measurement of the predetermined second crater processing time is completed, the second crater processing is ended. That is a consumable second electrode arc welding termination method.
[0040]
Next, a second embodiment of the welding end control method and welding robot of the present invention will be described.
[Example 2]
In Example 2, as shown in FIGS. 10, 14, and 15, feeding and energization of the preceding wire 3 are stopped at the welding end position P <b> 2, and the trailing wire 4 is moved while moving the welding torch in the welding direction. A welding end control method and a welding robot for performing a first crater process, and subsequently performing a second crater process by substantially stopping a welding torch.
[0041]
[Explanation of FIG. 11]
FIG. 11 shows that the leading tip 1 and the trailing tip 2 are angled with respect to the central axis of the nozzle 10 when the welding line WL used in the second embodiment is the X axis and the central axis of the nozzle 10 is the Y axis. It is a figure which shows the positional relationship of the leading wire front-end | tip 3a and the trailing-wire front-end | tip 4a when arrange | positioning.
In FIG. 11 in which the leading tip 1 and the trailing tip 2 are arranged at an angle with respect to the Y axis of the central axis of the nozzle 10, {circle around (1)} the leading tip angle α is determined by the center axis of the leading tip 1 being the center Y of the nozzle. (2) The trailing tip angle β is an angle in which the central axis of the trailing tip 2 is inclined with the receding angle β to the center Y axis of the nozzle. 3 or the standard protruding length L1 (for example, 20 [mm]) of the trailing wire 4 is obtained when the leading wire 3 or the trailing wire 4 protrudes from the tip of the leading tip 1 or the trailing tip 2 by a predetermined length. The length of the leading wire 3 or the trailing wire 4 to the tip position (tool center position) of the leading wire 3 or the trailing wire 4 is as follows. Lead wire and rear wire when projecting length is standard projecting length L1 A wire tip distance between the wires, which are predetermined set value.
[0042]
[Explanation of FIG. 12]
12 is a block diagram of the robot controller 27 when the welding end method or the welding end control method of the present invention is applied to the welding robot shown in FIG.
In FIG. 12, the work program file output circuit 29 stores (1) welding start parameters and (2) welding end parameters determined in advance in each welding section of the work piece 8.
Here, the above-mentioned “welding start parameter” means (1) the welding current value and welding voltage value of the preceding wire 3 and the succeeding wire 4 at the welding start position in each welding section, and (2) the normal welding speed. It is.
The “welding end parameter” is a condition for the first and second crater processes performed by the succeeding wire 4. (1) First crater process current value and first crater process voltage value and (2) ▼ Welding torch moving speed and welding torch moving distance (D1 shown in FIG. 10) and (3) second crater processing current value and second crater processing voltage value and (4) 2 crater processing time.
[0043]
Further, the first crater processing distance D1 may be set to, for example, {circle around (1)} “standard protrusion length distance between wire tips” L2. Alternatively, (2) the movement time of the welding torch during the first crater processing period of the trailing wire and the preceding wire may be set. In this case, (first crater processing distance) D1 = (moving speed of welding torch during first crater processing period) × (moving time of welding torch during first crater processing period). Alternatively, (3) “standard protrusion length distance between wire tips” L2 may be specified as a percentage and set by (first crater processing distance) D1 / L2 [%].
[0044]
In addition, according to the experiments by the inventors, the speed is decreased when moving from the normal welding speed to the first crater processing speed, so that the molten pool trace 13 is formed as shown in FIG. 5 of the prior art. Even if the pond is depressed, the molten pool in which the molten metal of the trailing wire is depressed can be sufficiently filled. Furthermore, since the first crater processing speed is low, the molten metal of the preceding wire 3 and the molten metal of the succeeding wire 4 are sufficiently fused without moving the trailing tip 2 to the welding end position. Therefore, as shown in FIG. 8, the first crater processing distance D <b> 1 may be shorter than “the distance between the wire tips of the standard protruding length” L <b> 2.
[0045]
In the electrode parameter output circuit 31 shown in FIG. 12, when the leading wire 3 or the trailing wire 4 protrudes from the tip of the predetermined leading tip 1 or the trailing tip 2 shown in FIG. “Standard protruding length of the preceding wire 3 or the succeeding wire 4” L1 (for example, 20 [mm]) and {circle around (2)} which are the lengths up to the tip position (tool center position) of the preceding wire 3 or the following wire 4 An electrode composed of “the distance between the wire tips of the standard protruding length” L2, which is the distance between the wire tips of the preceding wire and the succeeding wire when the protruding length of the leading wire 3 or the trailing wire 4 is the standard protruding length L1. The parameter is memorized.
In FIG. 12, the work program file output circuit 29 stores (1) welding start parameters and (2) welding end parameters determined in advance in each welding section of the work piece 8.
Here, the above-mentioned “welding start parameter” means (1) the welding current value and welding voltage value of the preceding wire 3 and the succeeding wire 4 at the welding start position in each welding section, and (2) the normal welding speed. It is.
[0046]
Further, the output signal of the work program file output circuit 29 is input to the welding torch moving path calculation circuit 32, and the joint angles of the manipulator 21 for moving the welding torch from the welding start position to the welding end position are calculated. Then, the calculated value of each joint angle is output to a servo control circuit 33 described later.
[0047]
The servo control circuit 33 receives the calculated values of the joint angles of the manipulator 21 for moving the welding torch from the welding torch moving path calculation circuit 32 and controls the manipulator 21.
[0048]
The preceding wire welding condition output circuit 35 receives a preceding wire welding start command signal S1 that instructs the preceding wire 3 to energize the welding wire from the welding torch movement path calculation circuit 32 when the preceding tip 1 reaches a predetermined welding start position. When input, a signal instructing energization of the welding current of the welding current value of the preceding wire 3 output from the work program file output circuit 29 is output.
The preceding wire welding power source device 23 energizes the preceding wire 3 with a welding current when a signal instructing energization of the welding current of the preceding wire is input from the preceding wire welding condition output circuit 35.
[0049]
The trailing wire welding condition output circuit 36 starts the trailing wire welding in which the trailing tip 2 reaches a predetermined welding start position and instructs the trailing wire 4 to energize the welding wire 4 from the welding torch movement path calculation circuit 32. When the command signal S2 is input, a signal for instructing energization of the welding current of the welding current value of the succeeding wire 4 output from the work program file output circuit 29 is output.
The power supply device 24 for the subsequent wire welding supplies the welding current to the subsequent wire 4 when a signal instructing the energization of the welding current of the subsequent wire is input from the subsequent wire welding condition output circuit 36.
[0050]
Next, the operation of the robot control apparatus 27 according to the second embodiment will be described with reference to the signal time chart of FIG. 13 and the flowcharts shown in FIGS.
[Explanation of FIG. 13]
FIG. 13 is a diagram illustrating signals output from the welding torch movement path calculation circuit 32 of the robot control apparatus 27 according to the second embodiment and the movement speeds of the leading tip 1 and the trailing tip 2. 13, (A) shows the elapsed time t of the preceding wire welding start command signal S1, and (B) shows the elapsed time t of the preceding wire welding end processing command signal S5. C) shows the elapsed time t of the moving speed of the preceding tip 1 and the succeeding tip 2. FIG. 10D shows the elapsed time t of the succeeding wire welding start command signal S2, and FIG. The time lapse t of the 1 crater processing command signal S6 is shown, and FIG. 8F shows the time lapse t of the second crater processing command signal S8. Here, in order to simplify the explanation, it is assumed that the path between the welding start position and the welding end position in each welding section is taught by one straight line.
[0051]
[Explanation of FIGS. 14 and 15]
14 and 15 are flowcharts illustrating the operation of the robot control device 27 according to the third embodiment. In step ST1 “electrode parameter setting step” shown in FIG. 14, the electrode parameter output circuit 31 is provided with (1) the standard protruding length L1 of the preceding wire 3 or the succeeding wire 4 and (2) the preceding wire 3 and the succeeding wire 4. The electrode parameters including “standard wire protruding distance between wire tips” L2 are set.
[0052]
In step ST2 “work program file setting step”, predetermined (1) welding start parameter and (2) welding end parameter in each welding section of the work piece 8 are set in the work program file output circuit 29.
[0053]
At step ST3 “electrode parameter and work program file input step” shown in FIG. 14 and at time t1 shown in FIG. 13, the welding robot system is activated and the electrode parameters set in the electrode parameter output circuit 31 and the work program file output circuit 29 And a normal welding speed at a predetermined welding start position in each welding section of the work piece 8 set to be output to the welding torch moving path calculation circuit 32.
Further, the welding current value and welding voltage value of the preceding wire 3 at the welding start position in each welding section determined in advance in each welding section of the workpiece 8 are output to the preceding wire welding condition output circuit 35, and the workpiece 8 is welded. (1) predetermined welding current value and welding voltage value of the succeeding wire 4 at the welding start position in each welding section, and (2) first crater processing current value and first crater processing voltage value. (3) The second crater processing current value and the second crater processing voltage value are output to the trailing wire welding condition output circuit 36.
[0054]
In step ST4 “Welding start position welding torch movement path calculation and output step” shown in FIG. 14, the welding torch movement path calculation circuit 32 calculates each joint angle of the manipulator 21 for moving the welding torch to the welding start position. Thus, the calculated values of the joint angles are output to the servo control circuit 33.
[0055]
At step ST5 “leading wire and subsequent wire welding start signal output step” shown in FIG. 14 and at time t2 shown in FIG. 13, the welding torch moves to the welding start position, and the joint angle at the welding start position described in step ST4 When the calculated value is reached, the welding torch moving path calculation circuit 32 outputs the preceding wire welding start command signal S1 to the preceding wire welding condition output circuit 35, and the subsequent wire welding start command signal S2. It outputs to the condition output circuit 36.
[0056]
In step ST6 “leading wire and succeeding wire energization start step” shown in FIG. 14, the leading wire welding start command signal S1 is input to the leading wire welding condition output circuit 35, and the trailing wire welding start command signal S2 is input to the trailing wire. When input to the welding condition output circuit 36, the preceding wire welding condition output circuit 35 and the succeeding wire welding condition output circuit 36 respectively supply welding to the preceding wire 3 and the succeeding wire 4 at the welding start position. The current value and the welding voltage value are output to the preceding wire welding power supply device 23 and the subsequent wire welding power supply device 24 to energize the preceding wire 3 and the following wire 4, respectively.
[0057]
In step ST7 “following wire crater processing welding end position welding torch moving path calculating step” shown in FIG. 14, the preceding wire welding start command signal S1 is input to the preceding wire welding condition output circuit 35, and the following wire welding start command signal is received. After S2 is input to the subsequent wire welding condition output circuit 36, the welding torch movement path calculation circuit 32 sends the first crater processing speed, which is the movement speed of the welding torch during the first crater processing period, from the work program file output circuit 29. And a first crater processing distance D1 (shown in FIG. 10) which is a moving distance of the welding torch and (3) a second crater processing time are input, and each of the manipulators 21 for moving the welding torch to the welding end position Calculate the joint angle.
[0058]
In step ST8 “leading wire and succeeding wire welding start completion signal output step”, when the arc 5 and the arc 6 are generated at the leading wire tip 3a and the trailing wire tip 4a, respectively, the leading wire welding condition output circuit 35 and after The row wire welding condition output circuit 36 outputs a preceding wire welding start completion signal S3 and a following wire welding start completion signal S4 to the welding torch movement path calculation circuit 32, respectively.
[0059]
When the preceding wire welding start completion signal S3 and the subsequent wire welding start completion signal S4 are input to the welding torch movement path calculation circuit 32 in step ST9 "first crater processing start position welding torch movement step" shown in FIG. Further, the joint angle of the manipulator 21 for moving the welding torch to the first crater processing start position P3 shown in FIG. 10 calculated by the welding torch moving path calculation circuit 32 in step ST7 shown in FIG. Output. As a result, the manipulator 21 starts a linear operation at a preset normal welding speed and performs normal welding.
[0060]
At step ST10 “first crater processing command signal output step” shown in FIG. 15 and at time t3 shown in FIG. 13, the welding torch moves to the first crater processing start position P3 shown in FIG. 10, and step ST7 shown in FIG. When the calculated value of the joint angle at the first crater processing start position P3 calculated in step S3 is reached, the welding torch movement path calculation circuit 32 outputs the preceding wire welding end processing command signal S5 to the preceding wire welding condition output circuit 35. The first crater processing command signal S6 is output to the trailing wire welding condition output circuit 36.
Further, the welding torch moving path calculation circuit 32 outputs the first crater processing speed to the servo control circuit 33.
[0061]
In step ST11 “preceding wire welding end processing step” shown in FIG. 15 and time t3 shown in FIG. 13, the preceding wire welding end processing command signal S5 is input from the welding torch moving path calculation circuit 32 to the preceding wire welding condition output circuit 35. The preceding wire welding power source device 23 performs the anti-stick process and the welding release process. Then, after the anti-stick process and the welding release process are completed, when the preceding wire welding condition output circuit 35 determines that there is no welding, the preceding wire welding end process completion signal S7 is output to the welding torch movement path calculation circuit 32. .
Here, the anti-stick process means that the motor feeds the wire by the inertial force even after the stop signal is input to the wire feeding device. Therefore, when the wire rushes into the molten pool and the molten pool cools, the tip of the wire adheres (sticks) to the weld metal. In order to prevent this sticking, after a stop signal is input to the wire feeder, a current smaller than the welding current value is applied to continue melting the wire and prevent the wire from being pushed into the molten pool. It is.
In the welding release process, for example, a short-circuit detection circuit or a welding current relay detects whether or not the tip of the wire is welded to the workpiece after energization of the wire is completed. And when welding is detected, it is the process which applies a no-load voltage between the front-end | tip of a wire and a to-be-welded object, energizes, burns up a wire, and cancels welding.
[0062]
In step ST12 "first crater processing step" shown in FIG. 15, when the first crater processing command signal S6 is input to the subsequent wire welding condition output circuit 36, the subsequent wire welding condition output circuit 36 The processing current value and the first crater processing voltage value are output to the power supply device 24 for the subsequent wire welding.
[0063]
At step ST13 “second crater processing start step” shown in FIG. 15 and at time t4 shown in FIG. 13, the trailing chip 2 moves to the second crater processing position P4 shown in FIG. 10, and at step ST7 shown in FIG. When the calculated value of the joint angle at the calculated second crater processing position P4 is reached, the servo control circuit 33 stops the manipulator 21, and the welding torch movement path calculation circuit 32 follows the second crater processing command signal S8. This is output to the row wire welding condition output circuit 36.
[0064]
In step ST14 “second crater processing step” shown in FIG. 15, when the second crater processing command signal S8 is input to the subsequent wire welding condition output circuit 36, the subsequent wire welding condition output circuit 36 The 2 crater processing current value and the second crater processing voltage value are output to the power supply device 24 for the subsequent wire welding, and measurement of the second crater processing time is started.
[0065]
When the succeeding wire welding condition output circuit 36 has finished measuring the second crater processing time at step ST15 “following wire welding end processing step” shown in FIG. 15 and at time t5 shown in FIG. The power supply device 24 performs an anti-stick process and a welding release process for the following wire. Then, after the end of the anti-stick process and the welding release process, the succeeding wire welding condition output circuit 36 outputs a succeeding wire welding end process completion signal S9 to the welding torch movement path calculation circuit 32 when it is determined that there is no welding. .
[0066]
In step ST16 “next welding section welding step” shown in FIG. 15, when the preceding wire welding end process completion signal S7 and the succeeding wire welding end process completion signal S9 are input to the welding torch movement path calculation circuit 32, FIG. Steps ST4 to ST15 shown in FIG. 15 are repeated to perform welding in the next welding section, and when the welding of all the welding sections set in the work program file output circuit 29 is finished, the activation of the welding robot is stopped.
[0067]
The welding end control method of the second embodiment described above is summarized as follows. In the electrode parameter output circuit 31, (1) the standard protruding length L1 of the preceding wire 3 or the succeeding wire 4 and (2) the “distance between the tip ends of the standard protruding length” L2 of the preceding wire 3 and the succeeding wire 4 are set. “Electrode parameter setting step” (step ST1) for setting the electrode parameters including,
A “work program file setting step” (step ST2) for setting (1) welding start parameters and (2) welding end parameters determined in advance in each welding section of the work piece 8 in the work program file output circuit 29;
The welding robot system is activated, and the electrode parameters set in the electrode parameter output circuit 31 and the normal program set at the predetermined welding start position in each welding section of the workpiece 8 set in the work program file output circuit 29 are as follows. The welding speed is output to the welding torch movement path calculation circuit 32,
The welding current value and the welding voltage value of the preceding wire 3 at the welding start position in each welding section predetermined in each welding section of the workpiece 8 are output to the preceding wire welding condition output circuit 35 to be welded. (1) welding current value and welding voltage value of the succeeding wire 4 at the welding start position in each welding section, and (2) first crater processing current value and first crater processing voltage value. And (3) “electrode parameter and work program file input step” (step ST3) for outputting the second crater processing current value and the second crater processing voltage value to the trailing wire welding condition output circuit 36,
The welding torch moving path calculation circuit 32 calculates each joint angle of the manipulator 21 for moving the welding torch to the welding start position, and outputs the calculated value of each joint angle to the servo control circuit 33 “Welding start position welding”. Torch travel route calculation and output step "(step ST4),
When the welding torch reaches the welding start position, the welding torch movement path calculation circuit 32 outputs the preceding wire welding start command signal S1 to the preceding wire welding condition output circuit 35, and the subsequent wire welding start command signal S2 A "preceding wire and succeeding wire welding start completion signal output step" (step ST5) to be output to the row wire welding condition output circuit 36;
When the preceding wire welding start command signal S1 is input to the preceding wire welding condition output circuit 35 and the following wire welding start command signal S2 is input to the following wire welding condition output circuit 36, the preceding wire welding condition output circuit 35 And the succeeding wire welding condition output circuit 36 supplies the welding current value and the welding voltage value supplied to the preceding wire 3 and the succeeding wire 4 at the welding start position, respectively, for the preceding wire welding power source device 23 and the succeeding wire welding. Output to the power supply device 24 and energize the leading wire 3 and the trailing wire 4 respectively.
The welding torch movement path calculation circuit 32 outputs a normal welding speed to the servo control circuit 33 “leading wire and subsequent wire energization start step” (step ST6), and the leading wire welding start command signal S1 is a leading wire welding condition. After being input to the output circuit 35 and the subsequent wire welding start command signal S2 being input to the subsequent wire welding condition output circuit 36, the welding torch movement path calculation circuit 32 is connected to the work program file output circuit 29 from the first (1) The first crater processing speed that is the moving speed of the welding torch during the one crater processing period, the first crater processing distance D1 that is the moving distance of the welding torch, and (2) the second crater processing time are input, and the welding torch is Calculate the joint angles of the manipulator 21 for moving to the welding end position. Flop "(step ST7),
When the arc 5 and the arc 6 are generated at the leading wire tip 3a and the trailing wire tip 4a, respectively, the leading wire welding condition output circuit 35 and the trailing wire welding condition output circuit 36 indicate the leading wire welding start completion signal S3 and the trailing line. A “preceding wire and succeeding wire welding start completion signal output step” (step ST8) for outputting the wire welding start completion signal S4 to the welding torch movement path calculation circuit 32, respectively;
When the preceding wire welding start completion signal S3 and the succeeding wire welding start completion signal S4 are input to the welding torch movement path calculation circuit 32, the welding torch movement path calculation circuit 32 moves to the first crater processing start position P3. A “first crater processing start position welding torch moving step” (step ST9) for outputting each joint angle of the manipulator 21 for moving the servo to the servo control circuit 33;
When the welding torch reaches the first crater processing start position P3, the welding torch movement path calculation circuit 32 outputs the preceding wire welding end processing command signal S5 to the preceding wire welding condition output circuit 35, and the first crater processing command The signal S6 is output to the trailing wire welding condition output circuit 36, and the welding torch movement path calculation circuit 32 outputs the first crater processing speed to the servo control circuit 33 "first crater processing command signal output step" (step ST10) )When,
When the preceding wire welding end processing command signal S5 is input from the welding torch movement path calculation circuit 32 to the preceding wire welding condition output circuit 35, the preceding wire welding power supply device 23 performs anti-stick processing and welding release processing, After the stick process and the welding release process are completed, when the preceding wire welding condition output circuit 35 determines that there is no welding, the preceding wire welding end process completion signal S7 is output to the welding torch movement path calculation circuit 32. Welding end processing step "(step ST11);
When the first crater processing command signal S6 is input to the trailing wire welding condition output circuit 36, the trailing wire welding condition output circuit 36 outputs the first crater processing current value and the first crater processing voltage value to the trailing wire welding. "First crater processing step" (step ST12) to be output to the power supply device 24
When the trailing chip 2 reaches the second crater processing position P4, the servo control circuit 33 stops the manipulator 21, and the welding torch movement path calculation circuit 32 sends the second crater processing command signal S8 to the subsequent wire welding. “Second crater processing start step” (step ST13) to be output to the condition output circuit 36;
When the second crater processing command signal S8 is input to the subsequent wire welding condition output circuit 36, the subsequent wire welding condition output circuit 36 outputs the second crater processing current value and the second crater processing voltage value to the subsequent wire welding. “Second crater processing step” (step ST14) for outputting to the power supply device 24 and starting measuring the second crater processing time;
When the trailing wire welding condition output circuit 36 completes the measurement of the second crater processing time, the trailing wire welding power source device 24 performs the antistic processing and welding release processing of the trailing wire, and performs antistic processing and welding. After the release process, when the succeeding wire welding condition output circuit 36 determines that there is no welding, the succeeding wire welding end process completion signal S9 is output to the welding torch movement path calculation circuit 32. This is a consumable two-electrode arc welding end control method consisting of “step” (step ST15).
[0068]
The welding robot of the second embodiment to which the welding end control method is applied is summarized as follows. The welding robot of the second embodiment includes a work program file output circuit 29 for storing (1) welding start parameters and (2) welding end parameters determined in advance in each welding section of the workpiece 8;
Electrode parameter output for storing electrode parameters consisting of predetermined (1) “standard protruding length of preceding wire 3 or trailing wire 4” L1 and (2) “distance between wire tips of standard protruding length” L2 A circuit 31;
(1) When the output signal of the work program file output circuit 29 is inputted, each joint angle of the manipulator 21 for moving the welding torch from the welding start position to the welding end position is calculated (in a servo control circuit 33 described later). ) Output the calculated value of each joint angle,
(2) When the welding torch reaches the welding start position, the preceding wire welding start command signal S1 is output to the preceding wire welding condition output circuit 35, and the following wire welding start command signal S2 is output to the following wire welding condition output circuit. 36, the normal welding speed is output to (servo control circuit 33 described later), and (3) when the welding torch reaches the first crater processing start position P3, the preceding wire welding end processing command signal S5 is output. (To a later-described preceding wire welding condition output circuit 35), a first crater processing command signal S6 (to a later-described subsequent wire welding condition output circuit 36) is output, and the first crater processing speed (servo control to be described later) is output. (4) When the trailing chip 2 reaches the second crater processing position P4, the second crater processing command signal S8 is output (following wire welding condition output circuit described later). The welding torch movement route calculation circuit 32 6) output,
(1) The calculated values of the joint angles of the manipulator 21 for moving the welding torch are input from the welding torch moving path calculation circuit 32 to control the manipulator 21, and (2) the trailing chip 2 is moved to the second crater processing position. A servo control circuit 33 for stopping the manipulator 21 when P4 is reached;
(1) When the preceding wire welding start command signal S1 is input, a welding current value and a welding voltage value supplied to the preceding wire 3 at the welding start position are output (to a power supply device for preceding wire welding 23 described later). (2) When the arc 5 is generated at the leading wire tip 3a, the leading wire welding start completion signal S3 is output to the welding torch moving path calculation circuit 32, and (3) the leading wire welding end processing command signal S5 is input. When it is done, a signal for instructing the anti-stick process and the welding release process of the preceding wire 3 is output (to the preceding wire welding power supply device 23 described later), and when it is determined that there is no welding, a welding torch movement path calculation circuit A preceding wire welding condition output circuit 35 for outputting a preceding wire welding end processing completion signal S7 to 32,
When a signal instructing energization of the welding current of the preceding wire is input from the preceding wire welding condition output circuit 35, the welding current is energized to the preceding wire 3, and command signals for anti-stick processing and welding release processing of the preceding wire 3 are received. When the preceding wire welding power source device 23 that performs anti-stick processing and welding release processing of the preceding wire 3 and (1) the succeeding wire welding start command signal S2 are input, When a welding current value and a welding voltage value supplied to the trailing wire 4 are output (to a trailing wire welding power source device 24 described later), (2) when the arc 6 is generated at the trailing wire tip 4a, A row wire welding start completion signal S4 is output to the welding torch movement path calculation circuit 32, and (3) when the first crater processing command signal S6 is input, the first crater processing current value and the first (4) when the second crater processing command signal S8 is input, the second crater processing current value and the second crater processing voltage are output. The value is output (to the power supply device 24 for the subsequent wire welding described later), the measurement of the second crater processing time is started, and (5) when the measurement of the second crater processing time is completed, A command signal for performing an anti-stick process and a welding release process is output (to a subsequent wire welding power supply device 24 described later), and when it is determined that there is no welding, the welding torch movement path calculation circuit 32 performs a subsequent wire welding end process. A trailing wire welding condition output circuit 36 for outputting a completion signal S9;
When a signal instructing energization of the welding current of the succeeding wire is input from the succeeding wire welding condition output circuit 36, the welding current is energized to the succeeding wire 4, and the anti-stick process and the welding release process of the succeeding wire 4 are performed. This is a welding robot provided with a power supply device 24 for the subsequent wire welding that performs an anti-stick process and a welding release process for the subsequent wire 4 when a command signal for performing the operation is input.
[0069]
【Effect of the invention】
The consumable two-electrode arc welding end method, the welding end control method, and the welding robot of the present invention stop the feeding and energization of the preceding wire 3 at the welding end position in the two-electrode one-torch consumable electrode arc welding end method. Then, the first crater process is performed with the trailing wire 4 at a welding speed slower than that during normal welding, and then the movement of the welding torch is substantially stopped to perform the second crater process. Thus, even at the welding end position, the weld bead width does not decrease or lack of penetration does not occur, the appearance of the weld bead is improved, and the weld joint strength can be ensured. In addition, when performing high-speed welding, crater treatment can also be performed on the depressed molten pool before performing crater treatment, so there is no weld pool mark at the welding end position, and there are defects such as cracks and shrinkage holes. It does not occur.
[Brief description of the drawings]
FIG. 1 is a diagram that best represents the features of the invention according to the present application;
FIG. 2 is a diagram for explaining a consumable electrode arc welding end method of a two-electrode one-torch method.
FIG. 3 is a diagram showing a general configuration of a two-electrode, one-torch welding robot.
FIG. 4 is a diagram for explaining a method of ending consumable electrode arc welding by a two-electrode one-torch method according to prior art 1;
FIG. 5 is a diagram for explaining a method of ending consumable electrode arc welding of the conventional electrode 1 of the conventional technique 1 following FIG. 4;
FIG. 6 is a view showing an apparatus for performing tandem arc welding according to prior art 2;
FIG. 7 is a time chart for explaining a control method at the end of welding according to the prior art 2;
FIG. 8 illustrates a case where the preceding wire 3 and the trailing wire 4 are fed and the trailing wire 4 performs the first and second crater processes in the consumable two-electrode arc welding end method according to the first embodiment of the present invention. It is a figure to do.
9 is a diagram for explaining a welding end method subsequent to FIG. 8 in the welding end method of Example 1. FIG.
FIG. 10 is a diagram for explaining the moving distance of the welding torch from the welding start position P1 to the first crater processing start position and the second crater processing position when the trailing wire 4 of the present invention performs crater processing. .
11 shows an angle for the leading tip 1 and the trailing tip 2 with respect to the central axis of the nozzle 10 when the welding line WL used in Example 2 is the X axis and the central axis of the nozzle 10 is the Y axis. It is a figure which shows the positional relationship of the leading wire front-end | tip 3a and the trailing-wire front-end | tip 4a when arrange | positioning.
12 is a block diagram of a robot controller 27 when the welding end method or the welding end control method of the present invention is applied to the welding robot shown in FIG. 3;
13 is a diagram illustrating a signal output from a welding torch movement path calculation circuit 32 of the robot control apparatus according to the second embodiment and movement speeds of a leading tip 1 and a trailing tip 2. FIG.
FIG. 14 is a flowchart illustrating the operation of the robot control apparatus 27 according to the second embodiment.
FIG. 15 is a flowchart showing the operation of the robot control apparatus 27 of the second embodiment following FIG.
[Explanation of symbols]
1 Leading chip
2 trailing chip
3 Lead wire
3a Lead wire tip
4 trailing wire
4a Trailing wire tip
5, 6 arc
7 molten pool
8 Workpiece
9 Weld beads
10 nozzles
11 Shield gas
13 molten pool trace
14 Welding torch
15, 16 Crater processing trace
21 Manipulator
23 Power supply device for leading wire welding
24 Power supply device for trailing wire welding
25 Lead wire feeder
26 Trailing wire feeder
27 Robot controller
29 Work program file output circuit
31 Electrode parameter output circuit
32 Welding torch movement path calculation circuit
33 Servo control circuit
35 Lead wire welding condition output circuit
36 Subsequent wire welding condition output circuit
41 Leading chip
42 Trailing chip
43 Workpiece
44 Power supply device for leading wire welding
45 Power supply device for trailing wire welding
46 Lead wire feeder
47 Subsequent wire feeder
48 Lead wire
49 trailing wire
50, 51 arc
52 molten pool
53 Weld Bead
54 Welding control device
55 Welding Robot
D1 First crater processing distance
I1 Current during normal welding of the lead wire 48
I2 Current when leading wire 48 is reduced
I3 Current during normal welding of the trailing wire 49
I2 Current when trailing wire 49 is decreased
E1 Voltage during normal welding of the lead wire 48
E2 Voltage when leading wire 48 is decreased
E3 Voltage during normal welding of the trailing wire 49
E4 Voltage when leading wire 49 is decreased
L1 Standard protruding length of leading wire 3 or trailing wire 4
L2 Standard overhanging distance between wire tips
L3 Total welding torch travel distance
L4 Welding torch travel distance for normal welding
P1 Welding start position
P2 Welding end position
P3 First crater processing start position
P4 Second crater processing position
S1 Lead wire welding start command signal
S2 Subsequent wire welding start command signal
S3 Lead wire welding start completion signal
S4 Subsequent wire welding start completion signal
S5 Lead wire welding end processing command signal
S6 First crater processing command signal
S7 Lead wire welding end processing completion signal
S8 Second crater processing command signal
S9 Subsequent wire welding end processing completion signal
T1 Waiting time to stop energization of the preceding wire 48
T1 Waiting time until the energization of the trailing wire 49 is stopped
α Leading tip angle
β trailing tip angle

Claims (5)

  In a consumable two-electrode arc welding completion method in which two wires are fed and welded in one torch, feeding and energization of the preceding wire are stopped at the welding end position, and the welding torch is moved in the welding direction at a normal welding speed. Consumable two-electrode arc welding in which the trailing wire performs the first crater processing while moving the first crater processing distance at a slower speed, and then stops the movement of the welding torch and the trailing wire performs the second crater processing. Termination method.   The consumable two-electrode arc welding end method, wherein the first crater processing distance according to claim 1 is a distance between wire tips of a standard protruding length.   A consumable two-electrode arc welding end method for calculating the first crater processing distance according to claim 1 from the first crater processing moving speed and the first crater processing moving time.   In a consumable two-electrode arc welding end method in which two wires are fed and welded in one torch, when the leading tip reaches the welding end position, the feeding and energization of the leading wire are stopped, and the welding torch is The trailing wire performs the first crater processing at the first crater processing current value and the first crater processing voltage value at the first crater processing speed slower than the normal welding speed while moving in the welding direction, and then the trailing wire When the crater reaches the second crater processing position, the welding torch is stopped, and the second crater processing is started and the predetermined second crater processing time is measured based on the second crater processing current value and the second crater processing voltage value. The consumable two-electrode arc welding end method that ends the second crater processing when the measurement of the second crater processing time is completed.   In the consumable two-electrode arc welding end control method in which two wires are fed and welded in one torch, when the preceding wire reaches the welding end position, that is, the trailing wire reaches the first crater processing start position. A first crater processing start position welding torch moving step for commanding the end of welding of the preceding wire, and a command for processing the first crater at the first crater processing speed at which the succeeding wire is slower than the normal welding speed. When the first crater process command step and the preceding wire welding end process command are input, the antistic process and the welding release process of the preceding wire are performed, and after the antistic process and the welding release process are completed, When it was determined that there was no welding, the preceding wire welding end processing step for processing the preceding wire welding end and the first crater processing were commanded A first crater processing step for outputting a predetermined first crater processing current value and a first crater processing voltage value, and stopping the welding torch when the succeeding tip reaches the second crater processing position, A second crater processing start step for instructing the second wire to perform the second crater processing; and a second crater processing current value and a second crater processing when the second wire is instructed to perform the second crater processing. A second crater processing step of outputting a voltage value, starting measurement of a predetermined second crater processing time, and ending the second crater processing when the measurement of the second crater processing time is completed; 2. When the measurement of the crater processing time has expired, perform anti-stick processing and welding release processing of the trailing wire, and after the anti-stick processing and welding release processing are completed, the trailing wire A consumable two-electrode arc welding end control method comprising a following wire welding end processing step for completing the following wire welding end processing when it is determined that there is no welding.

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