TW201417934A - Multi-pass welding device - Google Patents

Abstract

The multi-pass welding device of this invention is to generate full N-layer welding passes according to the pre-teaching basic welding line Ws comprising a welding starting point P2-1 and the welding ending point P3-1 and the offset amount set with respect to the basic welding line Ws. The multi-pass welding device makes the welding torch T move along the generated welding pass to perform welding. When confirming the action, the operator operates the teaching box to select one of the full N-layer welding passes. Afterwards, the robot arm control device calculates the moving target positions (P2-2, p2-3, etc.) on the welding pass. Then, after inputting moving signal from the teaching box, the robot arm control device will make the welding torch T move toward the calculated moving target positions. Under this circumstance, the welding pass with action to be confirmed can be immediately selected, so as to greatly shorten the confirmation time of position and posture of the robot arm.

Description

Multi-channel welding device

The present invention is directed to a multi-pass welding apparatus that reflects a particular amount of deviation to the taught basic weld line to produce a desired number of weld passes.

Multi-pass welding refers to a welding construction method in which a joint portion of a thick plate workpiece is repeatedly welded along a plurality of weld passes, and a joint is filled by a bead to join. When a robot using a teaching playback method is used to realize multi-pass welding, the robot must be taught its teaching points. However, if you want to teach the teaching points of all the welding tracks, the amount of work is very large. Then, for example, in the control method disclosed in Patent Document 1, only the basic weld line of the first track is taught, and after the second track, a specific offset amount is added to each teaching point of the first track. Thereby, since the plurality of weld passes are automatically generated, the teaching operation can be reduced.

4 is a block diagram of a multi-pass soldering device 51. As shown in FIG. 4, the robot control device RC outputs the motion control signal Mc according to the operation signal Ss from the teaching box TP, and outputs the welding command signal Wc to the welding power source WP at a specific time point. Further, the servo motor operation of the plurality of axes disposed on the robot R is controlled by the motion control signal Mc. When the above various signals are input to the welding power source WP, the welding power source WP supplies the welding voltage Vw and the welding current Iw to the robot R, respectively. Further, the welding power source WP controls the solenoid valve provided in the gas cylinder (not shown) and outputs the shielding gas. Further, the welding power source WP outputs a transmission control signal Fc to the wire conveying motor WM to drive the wire conveying motor WM. The robot R has a wire transfer motor WM, a welding torch T, and the like, and moves the front end position of the welding torch T corresponding to the operation signal Ss. The welded steel wire WR is passed through the welding torch T by the steel wire conveying motor WM, and is conveyed to the work object (that is, the workpiece W). Then, an arc A is generated between the welded steel wire WR and the workpiece W to weld the welded steel wire WR to the workpiece W.

The teaching box TP is a portable teaching operation panel and is connected to the robot control device RC. The operator uses the teach pendant TP to switch the reference coordinate system or the robot R to perform a jog feed, thereby teaching the position and posture of the first track of the robot R, that is, the teaching point. At this time, for each teaching point, the step number is sequentially given from 1. After the second pass, the amount of deviation from the teaching point of the first track is specified for each of the weld passes, thereby automatically generating. The teaching information input in the above manner is stored as a multi-pass welding program Td inside the robot control device RC.

The robot control device RC corresponds to the input from the teaching box TP, allows the robot to micro-transmit, or reproduces the robot R according to the multi-pass welding program Td.

Figure 5 is a plan view of the teaching cartridge TP. The direction indication key 41A is used to set a key for moving and rotating the robot R during micro-transmission. The step forward key 41B and the step backward key 41C are keys for sequentially moving the robot R to the teaching point when confirming the positional posture of the robot R at the taught teaching point. The step forward key 41B is operated when the robot R is moved in the order of the step number. The step back key 41C is operated when the robot R is moved in the reverse order of the step numbers. The display unit 43 displays the teaching contents of the multi-pass welding program Td, the total number of passes in the welding section for performing multi-pass welding, the current number of passes, various parameters required for the operation control of the robot, and the like.

6(a) and (b) are diagrams for explaining a weld bead formed on the basis of a basic weld line. In Fig. 6(a), the basic welding line Ws for the multi-pass welding of the workpiece W by the welding torch T and the teaching points indicating the start end and the end end of the basic welding line Ws are respectively shown. In this case, welding is started after the welding torch T moves from the approaching point P1 to the welding start point P2-1. Then, the welding torch T moves to the welding end point P3-1 while welding, and moves to the retreat point P4 after the welding is completed.

Fig. 6(b) shows the motion trajectory of three welding programs. In FIG. 6(b), a specific amount of deviation is set for the welding start point P2-1, and the welding start point P2-2 of the second track and the welding start point P2-3 of the third track are set. Moreover, a specific amount of deviation is set to the welding end point P3-1, and the welding end point P3-2 of the second track and the welding end point P3-3 of the third track are set. As a result, in addition to the basic welding line Ws of the first track of Fig. 6(a), a multi-pass welding program in which the welding line Ws2 of the second track and the welding line Ws3 of the third track are set is generated. In general, a total of six components of the position component and the posture component are set as the deviation amount.

In the case where the above-described three-way welding program is generated, the operation at the time of welding the welding torch T is as follows. That is, in the welding lanes of the first to third lanes, the welding torch T is welded from the impending point P1. After the start point P2-N moves, welding starts. Then, the welding torch T moves to the welding end point P3-N, and after the welding is finished, it moves to the retreat point P4. Further, N is 1 to 3, and the operation of the welding torch T is repeated three times. Alternatively, when the welding torch T is reciprocally movable, the welding torch T starts to be welded after moving from the approaching point P1 to the welding start point P2-1. Then, the welding torch T moves to the welding end point P3-1 while welding, and moves to the retreat point P4 after the welding is completed. Next, the welding torch T starts welding from the retreat point P4 to the welding end point P3-2. Then, the welding torch T moves to the welding start point P2-2 while welding, and moves to the approaching point P1 after the welding is completed. Then, after the welding torch T moves from the approaching point P1 to the welding start point P2-3, welding is started. Then, the welding torch T moves to the welding end point P3-3 while welding, and moves to the retreat point P4 after the welding is completed.

In the above multi-pass welding program, the weld bead after the second pass is automatically generated. Therefore, it is necessary to confirm that the jig or the processed object is not disturbed before the welding process, or whether the robot R has become the desired position and posture. The confirmation method is a method of causing the robot R to sequentially reach the respective teaching points by pressing the step forward key 41B or the step backward key 41C of the teaching box TP. In this case, the robot R is operated in the same manner as in the actual welding process, and the checking operation is performed.

However, in the above prior art, only the robot R can be sequentially reached to each teaching point. In this case, since it is necessary to confirm the operation while the robot R has to wrap around or reciprocate the number of all the weld passes, it takes a lot of time. In particular, the problem is more serious due to the thickness of the plate or the shape of the opening, in the case where the number of passes is as high as 100. In the above case, it takes a lot of time for the robot R to wrap around or reciprocate the number of all the weld passes.

Patent Document 1: Japanese Laid-Open Patent Publication No. SHO-58-187270.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multi-pass welding apparatus which can immediately select a weld bead to be confirmed by an operation.

In order to achieve the above object, a first aspect of the present invention provides a multi-pass welding apparatus which generates 2 or more deviations from a basic welding line including a welding start point and a welding end point, and a deviation amount set for the basic welding line. The welding path formed by the N layers of the integer is moved along the welding path to weld the welding torch. The multi-pass welding device includes: a welding path selection mechanism that selects one of the welding lanes of the entire N-layer; and a position calculation mechanism that calculates a moving target position of the welding torch in the welding path selected by the welding path selection mechanism; Generating agency, And generating a movement signal for moving the welding torch to the moving target position; and a welding torch moving mechanism for moving the welding torch to the moving target position calculated by the position calculating mechanism corresponding to the movement signal.

In the above-described multi-pass welding device, preferably, the welding torch position is in a state where the weld bead is at a specific position of the M-th layer weld bead of 1 or more and less than N, and the welding path is guided by the weld path selecting mechanism. At the time of the transfer operation, the position calculation means calculates the movement target position corresponding to the specific position in the (M+1)th layer weld bead.

In the above-described multi-pass welding device, preferably, in the state where the welding torch position is at a specific position of the L-th layer weld bead of 2 or more and less than N, the reverse transfer operation of the weld bead is performed by the weld bead selection mechanism. At this time, the position calculation means calculates the movement target position corresponding to the specific position in the (L-1)th weld bead.

Preferably, the multi-pass welding device further includes a display mechanism for displaying a welding start point or a welding end point in the all-N welding path as a point information on a plane orthogonal to the welding traveling direction; The track selection mechanism selects the weld pass by selecting any one of the point information displayed by the display mechanism; the position calculation mechanism calculates the welding start point or the welding end point in the selected weld pass as the moving target position. Out.

In the above multi-pass welding apparatus, preferably, the display mechanism assumes that the bead generated by the all N-layer welding path is displayed.

A‧‧‧Arc

Fc‧‧‧ transmission control signal

Iw‧‧‧ welding current

Mc‧‧‧ motion control signal

Of‧‧‧ deviation file

P1‧‧‧ imminent

P4‧‧‧ Retreat point

P2-1, P2-2, P2-3‧‧‧ welding starting point

P3-1, P3-2, P3-3‧‧‧ welding end point

R‧‧‧ robot

RC‧‧‧manipulator control unit

Rg‧‧‧layer range

Ss‧‧‧ operation signal

T‧‧‧ welding torch

Td‧‧‧multiple welding program

TP‧‧‧Teaching Box

Vw‧‧‧ welding voltage

W‧‧‧Workpiece

Wc‧‧‧ welding command signal

Ws‧‧‧Basic welding line

Ws2, Ws3‧‧‧ welding line

WM‧‧‧Steel wire transfer motor

WP‧‧‧ welding power supply

WR‧‧‧weld steel wire

1, 51‧‧‧ multiple welding devices

2‧‧‧Key input monitoring department

3‧‧‧Teaching and Processing Department

5‧‧‧ Hard disk

7‧‧‧Mobile target position calculation unit

9‧‧‧Action Control Department

10‧‧‧TP interface

11‧‧ Explain the Executive Department

12‧‧‧Drive Command Department

21‧‧‧CPU

22‧‧‧ROM

23‧‧‧RAM

41‧‧‧ keyboard

41A‧‧‧direction indicator

41B‧‧‧Step forward button

41C‧‧‧Step Back button

43‧‧‧Display Department

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a functional block diagram of a multi-pass soldering apparatus of the present invention.

Fig. 2 is a perspective view for explaining a switching operation of a weld bead.

Fig. 3 is a view showing the welding start point in each weld bead as a point information on a plane orthogonal to the traveling direction of the welding.

Figure 4 is a block diagram showing the structure of a multi-pass welding device.

Figure 5 is a plan view of the teaching box.

6(a) and 6(b) are perspective views for explaining a weld bead formed on the basis of a basic weld line.

[First embodiment]

Hereinafter, a specific first embodiment of the multi-pass welding apparatus 1 of the present invention will be described.

As shown in Fig. 1, the teach pendant TP is the same as the prior art, and is a portable operating device for making a multi-pass welding program. The teaching box TP is a welding path selection mechanism for selecting a weld bead when the operation of the multi-pass welding program is confirmed. The robot R is also configured to guide the front end of the welding torch T shown in Fig. 4 to the instructed position and posture, as in the prior art. That is, the robot R is a welding torch moving mechanism for guiding the welding torch T to a moving target position in the selected weld bead.

Next, the robot control device RC as a position calculating means will be described.

As shown in Fig. 1, the robot control device RC is composed of a CPU 21 which is a central processing unit, a ROM 22 in which software programs or control parameters are stored, a RAM 23 as a temporary calculation area, and a microcomputer including various memories. The TP interface 10 is used to connect the teach pendant TP to the robot control device RC. The hard disk 5 is a non-volatile memory in which a plurality of welding programs Td or an offset file Of, which will be described later, are memorized.

A software program for performing various processes is stored in the ROM 22. Further, the robot control device RC includes a monitor unit 2 for key input, a teaching processing unit 3, a movement target position calculation unit 7, an operation control unit 9, an explanation execution unit 11, and a drive command unit 12. Each of the processing units executes various processes in accordance with a control signal from the CPU 21.

The key input monitoring unit 2 monitors the operation signal Ss input when the keyboard 41 of the teaching box TP shown in Fig. 5 is operated. The monitoring unit 2 that inputs the key analyzes the operation signal Ss from the teaching box TP, and notifies the instruction processing unit 3 or the interpretation execution unit 11 of the teaching information.

The teaching processing unit 3 creates a multi-pass welding program Td in accordance with the position and posture coordinate value at the teaching point notified from the monitoring unit 2 input by the key or the deviation amount from the basic welding line in the welding track after the second track. And remember on hard drive 5. For example, a welding start point, an intermediate point, a welding end point, and the like which constitute a basic welding line can be used as teaching points. The amount of deviation can be included as internal information in the multi-pass welding program Td or as a deviation file Of which is indirectly referred to from the multi-pass welding program Td.

In order to confirm the position and posture of the robot R, the operator has to reproduce the created multi-pass welding program Td by a manual operation at a low speed. In this case, the interpretation executing unit 11 reads the multi-pass welding program Td for each teaching point and analyzes the contents of the multi-pass welding program Td. Then, when it is necessary to drive the robot R, the interpretation executing unit 11 outputs control information such as the type of command required for driving, the position and posture value, and the like to the operation control unit 9. The motion control unit 9 performs a track plan or the like based on the control information, and outputs the motion control signal Mc to the robot R via the drive command unit 12. The robot R is driven and controlled according to the motion control signal Mc.

When the selection operation of the plurality of weld passes stored in the multi-pass welding program Td is performed, the interpretation executing unit 11 stores the selected weld pass number in the RAM 23, and requests the moving target position calculation unit 7 to move the target in each weld pass. The calculation of the location. The movement target position calculation unit 7 calculates the movement target position in the selected weld bead and stores it in the RAM 23.

Next, the action of confirming the position and posture of the robot R using the created multi-pass welding program Td will be described.

Fig. 2 shows each of the welding start points and the welding end points in the three-way welding program. Specifically, a specific amount of deviation is set for the welding start point P2-1, and the welding start point P2-2 of the second track and the welding start point P2-3 of the third track are respectively set. Moreover, a specific amount of deviation is set to the welding end point P3-1, and the welding end point P3-2 of the second track and the welding end point P3-3 of the third track are respectively set. The basic weld line Ws is formed by the welding start point P2-1 and the welding end point P3-1.

(1. The beginning of the low speed operation of the multi-pass welding program)

When the operator selects the multi-pass welding program Td that has been created, and presses the step forward button 41B shown in FIG. 5 once, the welding torch T moves from the approaching point P1 to the welding start point P2-1.

When the welding torch T is pressed again at the welding start point P2-1, the step forward button 41B is pressed again, and the welding torch T moves from the welding start point P2-1 to the welding end point P3-1 as in the past. In this regard, in the present invention, in order to easily confirm the position and posture of the welding torch T in each of the weld passes, a weld bead selection mode in which the moving direction of the welding torch T is used as the welding path arrangement direction is prepared.

Hereinafter, the action of pressing the step forward key 41B or the step backward key 41C in a state where the weld pass selection mode has been selected will be described.

(2. Forward operation/retraction operation in the direction of welding path at the welding start point)

When the step forward key 41B is pressed once in the state in which the weld pass selection mode has been selected, the interpretation execution unit 11 requests the movement target position calculation unit 7 to calculate the movement target position. The movement target position calculation unit 7 calculates the position and posture of the welding start point P2-2 of the second track based on the set deviation amount, stores it in the RAM 23, and notifies the operation control unit 9. The motion control unit 9 is for welding When the torch T moves to the calculated moving target position, the drive command unit 12 outputs the operation control signal Mc to the robot R. As a result, the welding torch T moves to the welding start point P2-2 of the second track.

Similarly, when the welding torch T is pressed once in the state of the welding start point P2-2 of the second track, the welding torch T moves to the welding start point P2-3 of the third track. After the step forward button 41B is pressed again, the welding torch T moves to the welding start point P2-1 of the first track and returns to the original position. Of course, by pressing the step back button 41C, the welding torch T can be moved in the opposite direction to the arrangement of the weld tracks.

In addition, the weld bead selection mode and the normal mode may be switched by a specific menu, or the specific operation key of the teaching box TP may be pressed to switch to the weld bead selection mode. In this case, the step forward button 41B or the step back button 41C is pressed while pressing a specific operation key, thereby moving the welding torch T to the next weld bead.

Further, for example, when the welding torch T is moved from the welding start point P2-1 to the welding start point P2-2 of the second track, if the process is switched to the normal mode and then the step forward key 41B is pressed, the same as in the past, The welding torch T can be moved from the welding start point P2-2 of the second track to the welding end point P3-2.

(3. Forward operation/retraction operation in the direction of alignment of the weld bead at the end of welding)

After the step forward key 41B is pressed once at the welding end point P3-1, the welding torch T can be sequentially moved to the welding end point P2-3 of the second track and the third track by the same processing as described above. Welding end point P3-3.

(4. Forward operation/retraction operation in the direction of the welding path at any position of the welding section)

The welding torch T may be located at any position in the welding zone (for example, if it is the first track, it is an arbitrary position between the welding start point P2-1 and the welding end point P3-1). Even in the above case, the amount of deviation can be reflected in the current position and posture value. Thereby, the welding torch T can be moved to the position corresponding to the first track in the second track and the third track, respectively.

As described above, according to the present invention, when the operation of the multi-pass welding program is confirmed, the welding path to be operated can be immediately selected by a simple operation. Thereby, the time required for the position and posture confirmation of the robot R in each weld bead can be greatly shortened.

Further, in the first embodiment, the movement signal for moving the welding torch T to the moving target position is generated by the teaching box TP as the movement signal generating means, and is operated. The step forward button 41B or the step forward button 41B of the teaching box TP is output, but is not limited thereto. For example, a signal input from the outside to the robot control device RC may be used as a mobile signal, or another operating mechanism different from the teaching box TP may be used for inputting a mobile signal.

[Second embodiment]

Next, a specific second embodiment of the multi-pass welding apparatus 1 of the present invention will be described. In the second embodiment, the welding start point or the welding end point in each weld bead is displayed as point information on the plane orthogonal to the welding traveling direction, and is displayed on the display portion 43 of the teaching box TP shown in Fig. 5 . Then, the operator can select the welding path which is the destination of the welding torch T by using the point information displayed on the display unit 43.

As shown in FIG. 3, the display portion 43 displays the workpiece W and the welding torch T in a hypothetical manner. Further, on the screen of the display unit 43, the welding start points in the respective weld passes on the opening plane of the workpiece W (that is, the respective welding start points of P2-1, P2-2, and P2-3 shown in Fig. 2) ) is portrayed as a defect. The drawing position of the defect can be easily calculated from the position of the welding start point as the reference and the amount of deviation set for each welding start point. In addition, although FIG. 3 shows only the welding start point, it is also possible to switch to the welding end point as the object of display.

Further, in the configuration of Fig. 3, it is more preferable to display the lamination range Rg of the bead formed by all the weld passes. The lamination range Rg is calculated based on known values such as the amount of conveyance of the welded steel wire, the welding time, and the sectional area of the opening.

As described above, in the second embodiment, the position and posture of the welding torch T in each of the weld passes are graphically displayed on a plane orthogonal to the traveling direction of the welding. Therefore, the operator can easily confirm the difference in position of the welding torch T between the weld passes.

In the configuration of FIG. 3, preferably, the welding torch T is further guided to the button of the teaching box TP, or directly clicks on the screen to select any one of the points of the welding start point. At the position corresponding to the selected defect. In other words, when the operator selects the defect, the step forward button 41B shown in FIG. 4 can be pressed in the same manner as in the first embodiment to move the welding torch T to the position at the welding start point of the selected defect. posture. The specific processing flow can be the same as that of the first embodiment.

Mc‧‧‧ motion control signal

Of‧‧‧ deviation file

R‧‧‧ robot

RC‧‧‧manipulator control unit

Ss‧‧‧ operation signal

Td‧‧‧multiple welding program

TP‧‧‧Teaching Box

1‧‧‧Multiple welding devices

2‧‧‧Key input monitoring department

3‧‧‧Teaching and Processing Department

5‧‧‧ Hard disk

7‧‧‧Mobile target position calculation unit

9‧‧‧Action Control Department

10‧‧‧TP interface

11‧‧ Explain the Executive Department

12‧‧‧Drive Command Department

21‧‧‧CPU

22‧‧‧ROM

23‧‧‧RAM

Claims (5)

A multi-pass welding device is a welding track composed of N layers of 2 or more integers based on a basic welding line including a welding start point and a welding end point, and a deviation amount set for the basic welding line. And welding the welding torch along the welding path to perform welding; characterized in that: a welding channel selection mechanism is selected, one of which is selected one of the welding lanes of all N layers; and a position calculation mechanism calculates the welding channel selection mechanism a moving target position of the welding torch in the selected welding track; a mobile signal generating mechanism generating a movement signal for moving the welding torch to the moving target position; and a welding torch moving mechanism corresponding to the moving signal The welding torch is moved toward the moving target position calculated by the position calculating means. In the multi-pass welding device of claim 1, wherein the welding torch is in a specific position of the M-th layer weld bead of 1 or more and less than an integer of N, when the welding path is selected by the welding path selection mechanism In the forward transfer operation, the position calculating means calculates a moving target position corresponding to the specific position in the (M+1)th layer weld bead. The multi-pass welding device of claim 1 or 2, wherein the welding torch position is in a state of a specific position of the L-th layer weld bead of 2 or more and less than an integer of N, by the welding path selection mechanism When the welding path is reversely conveyed, the position calculating means calculates a moving target position corresponding to the specific position in the (L-1)th layer weld bead. The plurality of welding devices of claim 1 further comprising a display mechanism for vertically intersecting the welding progress direction in the welding start point or the welding end point of the entire N-layer weld bead. Displaying by point information; the weld path selection mechanism selects a weld track by selecting any one of the point information displayed by the display mechanism; the position calculation mechanism starts the welding in the selected weld pass The point or the welding end point is calculated as the moving target position. A multi-pass welding device according to item 4 of the claim, wherein the display mechanism assumes a bead formed by all of the N-layer weld passes.