JPS6233062A - Automatic welding equipment - Google Patents

Abstract

PURPOSE:To realize an unmanned welding work by correcting automatically a part of a welding condition in accordance with a variation of a groove width or a groove sectional area of an object to be welded, based on an input which has been set and information which has been taught. CONSTITUTION:An automatic welding device is constituted of a control device 30, a welding head 31 and a welding power source 8. On a welding torch 13, each X, Y and Z axis driving motor 32, 33 and 34 is provided, and also position detectors 35, 36 and 37 are provided, respectively. Also, D/A converters 14, 17 are placed between an inputting/outputting circuit 7, and a driving circuit 15 and an amplifier 18. A welding condition is stored in advance in a RAM of a storage part 5 through a control part 4, and teaching of each intersection of a groove of both ends of a weld zone is executed. When welding is started, the welding condition is corrected successively and automatically in accordance with a variation of a groove width and a groove sectional area, based on a set input of the storage part 5 and teaching information. Since a deposition quantity is controlled automatically, an unmanned work can be realized.

Description

[Detailed Description of the Invention] [Industrial Application] The present invention relates to an automatic welding device for performing arc welding on objects to be welded, such as steel frames, which have a straight welding line and a weld groove. It is something.

[Conventional O) technology]

In recent years, automation of arc welding has been promoted, and butt welding of straight sections or multilayer welding with grooves, which are relatively simple welding and are considered easy to automate,
Gap management of the welding groove during tacking is rarely performed accurately, and this is a major barrier to automatic welding.

Conventionally, there has been a device of this type as shown in FIG. FIG. 12 is a plan view and a front view showing an example of an object to be welded. In Fig. 12, (1) is the object to be welded, (2)
is the bath welding groove, the X direction is the welding direction, and the Y direction is the welding groove width direction.2 In Fig. 11, (3) is the control device that is the central part of the automatic welding equipment, and (4) is the control device that is the central part of the automatic welding equipment. (5) a control unit for
is a random access memo in the storage section of each hidden data! J(
RAM), (6) is a welding condition setting section consisting of keyboard switches and a data display section, and ball (7) is an input/output between external equipment and the control section (4). The input/output circuit (8) that handles the welding power source is connected to the control unit (4) through the input/output circuit (7). (9) is for welding, and as a drive source 2 is an X-axis drive motor αQ that moves the entire welding machine (9) in the welding direction, and a Y-axis drive motor that moves it in the groove width direction. The X-axis drive consists of a potentiometer (6), a welding torch (2), etc. that are engaged to change the phase as the Y@B drive motor αη rotates. Control unit for motor αO (4)
This is a D/A converter for D/A converting the welding speed command value of the opening, and is connected to the X-axis drive motor output through the motor drive circuit side. αη is the output of the oscillation pattern from the control unit (4). An amplifier (
) Connected to the Y-axis drive motor wholesale through QLa.

Further, a fine adjustment volume is provided for the D/A converted welding speed command value and oscillation pattern command value, and an input/output circuit (7) is provided for controlling the welding current value command. It is directly connected to welding power 5 (8) through the D/A converter wire at the top and via an arc detection signal line, etc. Furthermore, & is connected to welding torch 0 from welding source 11 (8). On the other hand,
The Y-axis drive motor (6) can move the welding torch (toward) in the width direction, and the X-axis drive motor α1 can move the entire welding direction (9) in the welding direction. The operation of the primary unit, which is movable and arranged in a rotary manner, will be explained below.

Before starting welding work, the operator must first check the condition setting section (6).
Data are set regarding various conditions for welding. Welding conditions that should be set include welding electric current, welding speed,
Settings such as oscillation width and oscillation traverse time are made using the keyboard switches in the condition setting section (6).
The set data is sent to the storage unit (5) via the control unit (4).
It is stored in 几mu M.

When the welding start command is sent from the condition setting 1(a) to the control unit (4), the control unit (4) starts controlling the welding head (9) and welding t# (8) according to the welding seed. Regarding the welding speed, the preset setting value is stored in the memory (
5) and through the input/output circuit (7).
/ A After the analog value ζζ is converted in the transformer α, the motor drive circuit (to) converts the X-axis drive motor α
Drive the Q and control the movement of the welding direction (9) in the welding direction.During welding, the operator tends to overlook the arc condition and makes fine adjustments so that the welding speed can be adjusted to the set value. A volume αe is installed to increase or decrease the welding speed as appropriate. If the width of the groove (2) is relatively wide, the welding torch (2) is controlled to move in the groove width direction (oscillation width The setting conditions are the oscillation width, the oscillation traverse time, and the stop time at both ends, which are set by the condition setting section (6) in the same way as the welding speed.The oscillation pattern is determined by the eight conditions described above.

The output WI command value of the oscillation pattern is calculated as position information after the control unit (4) reads the above three conditions from the storage unit (5), and is continuously outputted from the control unit (4) as position information on the Y axis with respect to the time axis. 8 control units (4
), the command value passes through the input/output circuit (7) and is then converted into an analog value at the D/A converter α.This analog value is amplified by the amplifier (to) a9, and the Y-axis This leads to the drive motor (b).

On the other hand, a potentiometer (2) is engaged with the Y411 drive motor αη, forming a generally well-known servo system. The error signal between the oscillation pattern output command value and the output voltage of the potentiometer @ is compared and amplified.
This signal drives the Y-axis drive motor αυ, which is controlled to eliminate the above-mentioned error. Also, during welding, the operator adjusts the oscillation width to the set value without checking the width of the welding groove, the arc condition, etc. A fine adjustment volume is provided for fine adjustment, and the operator can increase or decrease the oscillation width as appropriate.The set value of the welding current is read out from the memory unit (5).
, = After that, it passes through the input/output circuit (7) and the D/A converter @ to become the normal pressure command for the welding power source and determine the welding current. [Problem to be solved by the invention] The conventional device has the above-mentioned Therefore, if the width of the welding groove differs between the welding start point and welding end point as shown in Fig. 12, the operator must always adjust the oscillation width and welding speed using the fine adjustment volume. However, there are many problems such as individual differences easily appearing in the one-time operation of adjusting the torque, and the current situation is far from unmanned. So,
By automatically correcting the welding conditions and controlling the amount of welding even when the groove widths at both ends of the welding point are different, we have developed a device that can obtain a uniform reinforcement height and achieve unmanned work. The purpose is to obtain.

[First Means to Solve the Problems] The automatic welding device according to the present invention has a self-propelled welding head with an oscillation function, and performs arc welding on a workpiece having a weld groove. , a means for setting and inputting predetermined welding conditions at a specific position of the workpiece, and a means for correcting a part of the welding conditions according to a change in the groove width or a change in the groove cross-sectional area of the workpiece. Based on the means for teaching the positions of the welding grooves at both ends of the welded object and the positions of both ends of the welding part of the welded object, and the T-co information input and taught by each of the above means, [Function] According to the present invention, the structure includes a means for automatically correcting a part of the welding conditions according to a change in the groove width or a change in the groove cross-sectional area of the workpiece, and 1). , a part of the welding conditions such as the oscillation width is automatically corrected in accordance with a change in the groove width or a change in the groove cross-sectional area of the workpiece.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. Fig. 1 is a block diagram of the configuration of the embodiment, Fig. 2 is a plan view showing the positional relationship between the welding head and the workpiece, Fig. 8 is a side view thereof, and Fig. 4 shows the operating section. Components whose functions are similar to those of the first factor in the explanatory diagram of the conventional device are designated by the same reference numerals, and the explanation thereof will be omitted.

(2) is a control device which is the central part of automatic welding equipment, and (cl) is a control device for welding. To welding - Lid C (υ is a drive source to welding - Lid C31) The X-axis drive motor (to) moves the entire body in the welding direction, the Y@ drive motor (to) to move it in the groove width direction, welding Moving torch α3 vertically 2
It has a shaft drive motor (b). Each drive mechanism is equipped with a position detector, including a pulse encoder (to) for the X-axis drive motor (a), a potentiometer (to) for the X-axis drive motor (to), and a potentiometer (to) for the In the example, each pulse encoder (2) is engaged so as to vary its output in accordance with the rotation of the motor.

A left/right adjustment volume (to) for moving the entire stroke of the Y-axis is provided between the D/A converter αη for Y-axis movement and the amplifier (to).

- There is a pulse counter (to) between the pulse encoder and the input/output circuit (7), and the input/output circuit (7)
A counter reset signal line (G) is connected from this point.

The Y-axis potentiometer (to) is a component of the servo system as in the conventional device, and its position information can be input to the input/output circuit (7) through the A/Di converter. The structure is as follows.

The first Z-axis drive motor (to) is driven by a drive circuit to rotate at a constant speed in response to a rotation command from the control unit (4). Furthermore, a pulse counter θ is connected between the two-axis pulse encoder ■ and the input/output circuit (7) as in the case of the X-axis.
1, and the counter reset from the input/output circuit (7)...
The signal line (goods) is connected.

Furthermore, the input/output circuit (7) is connected to an operating section (g) shown in Fig. 4 for issuing various commands, and a left/right adjustment volume (to) is provided on this operating section (c). There is.

It is fixed to the object to be bathed (1) by one guide rail that guides the second plate (in Fig. 3, the gloss is welded to the lid C3). el) is arranged at 4fJ so that it can rotate on the guide rail group with running wheels and move the welding/retro υ in the X-axis direction, 63 is 1 piece provided on the guide rail group, Q is for welding with pinion gear,
It is engaged with the rotating shaft of the X-axis drive mechanism of the lid 6υ, and is arranged so as to mesh with U,..., and R.

(Foundation) to welding.The Y-axis drive mechanism of Lido C1η
Guide bar (b), which is a guide bar that slides in the axial direction
A mounting bracket is fixed to the tip, and a two-axis drive mechanism is also attached.

6η is movable up and down (2 axes) using a 2-axis drive mechanism with a slide blow I, and a welding torch 0 is attached. The opening point is the welding start point, and (to) the welding end point. It is.

In Fig. 4, . . . is 1 step, 7 steps, and 1 step, and βυ is 1 point memory, 1 step, and 1 point. The first part is an LED (light emitting diode) to display the step number, and the ring is the LED at the end to display the point number.
D, (Foundation) 1st wheel is welding, Lido 61) is ``forward'' in the x4@ direction, or Tkoha] Reverse - I. In the two-axis direction, the "raise" and "lower" positions are used for "lowering". In addition, when the adjustment volume (to) is turned to the right, the welding torch screams and the welding head 61
) side and counterclockwise to move away from the welding lid 3]).

The first switch (to) is the first switch that commands the start and stop of welding. - is the reset/reset switch for the X-axis pulse counter (to) and the Z-axis pulse counter.
It's J Chi.

Next, the operation of this embodiment will be explained. Before starting welding work, the operator sets data for welding conditions and teaches the positions of each intersection that makes up the weld groove at both ends of the welding location.

The welding conditions are set using the condition setting section (6) in Fig. 1. All the welding conditions to be set are coded, and the data must be set by specifying the code number.
Once input, the data is stored in the RAM of the storage unit (5) via the control unit (4). Note that a part of the internal configuration of the storage section (5) is shown in FIG. Here I is welding current, ■
represents the welding voltage, F represents the welding speed, and other factors such as the oscillation width and the oscillation traverse time are encoded and stored. It should be noted here that the setting data is the welding conditions between the welding start points.

Next, the relative positions of the intersection points forming the welding groove are taught at the welding start point (g) and the welding end point.

First, move the welding torch (to) a little in front of the welding start point, then press the X-axis inching switch and the button to start welding.

The welding torch is lowered using the 2-sui-rich ring and stopped when its tip is located below the bottom of the groove. Next, press the reset switch. As a result, the X-axis pulse counter (to) * Z-axis pulse counter (to) are reset to the reset signal line) and (through 44), and furthermore, the station lib telephone number LEDIII and point numbers LP, D $ 3 becomes 10'.Next, to move the welding torch (to) to the welding start point (g), point Pl, press (to), etc. In Fig. 5, each inching operation is stopped at the position where the welding wire of welding torch 0 (not shown, the point is the point) comes into contact with P+, and the When you press , the ``Step No. 7'' display LED 13 will display llj, then press the 1 point memory switch 11), and as a result, ``1'' will be displayed on the ``Point No. 7'' display LED ring.
The position information is stored in the storage unit (5).This position information is generated by the following process.When the X-axis motor (a) rotates, the pulse encoder (to)
A pulse signal is sent out, the pulse counter (to) is reset, and the number of pulses after one is counted.This value is stored as 1 point and is stored in the input/output circuit by pressing switch 6]. In addition to (7), the control section (4)
This is stored in the storage section (5). The Z-axis is also stored by the same operation; in other words, a pulse signal is sent from the pulse encoder (9) by rotating the two-axis motor, and the pulse signal is sent out from the pulse encoder (9). The number of pulses after this is counted. This value is stored in the memory section (5) through the input/output circuit (7) by pressing the 1-point memory switch 6υ and then through the control section (4).

Regarding the Y-axis, the information of the A/D converter (current potentiometer α through 4 swords) is further transferred to the input/output circuit (7
) is stored in the storage unit (5), then the ink operation (from here on, the welding torch (to) is fully moved to point P2,
After positioning the welding torch (to) in the same way as at point P1, press the 1 point memory switch 11. Press . As a result, 1 point number 1 display LED branch is "2"
'' will be displayed on the sidewalk, and its position information will be stored in the storage unit (5) as a welding start command, that is, the position of point 2 of stave 1. P4. P
Repeat for s to teach each point. Next, the welding head 431) moves to the welding end point - point l.
Move the welding torch A3 and press the ``ST, Hl button'' button to make the ST knob number LED ``2'' display.Here, as with the welding start point ■, point P1~
Teach about Ps Step 6 and above to set the welding conditions and teach the positions of each intersection that makes up the weld groove between the welding start point and welding end point. Move D to the appropriate starting position on the side of the welding start point.

Next, the operator presses the "Welding Start/Stop" switch, and the welding torch (to) starts welding.
The command to the "Stop" switch is sent to the input/output circuit (7).
) is taken into the control unit (4), the control unit (4) decodes that it is a welding start command, and sequentially reads out the welding condition data necessary for welding from the storage unit (5). To welding - I draw υ, start the first calculation of output control to the welding power source (8), among which, the calculation according to the present invention will be detailed, and the explanation of other calculations will be omitted. Figure 8 shows an overview of preliminary calculations at the start of welding.

It is shown in FIG. Calculation gI performs preliminary calculations regarding the oscillation rate, and Calculation ■ performs preliminary calculations regarding the welding speed. Read from part (5) - Stave 7 in the direction of the It is determined by

Next, the control unit (4) reads out positional information regarding each intersection that constitutes the groove, which is stored in the storage unit (5).

From this position information, welding start point (g) and welding end point (g)
), calculate the length of each side that makes up the groove, and
B Figure lIo -1rs, lxo, lz+
(7) Replace it with a value and temporarily store it in the storage unit (5) again.

Next, it is temporarily stored in the storage unit (5), and one of the groove dimensions is
Root gap le between welding start point - and welding end point (to)
a.

Since the oscillation width needs to be increased or decreased in proportion to the change in the groove width as welding progresses, the oscillation amplitude at the welding end point (2) is W1 1+0.

As mentioned above, the set oscillation amplitude W is the data at the welding start point -, therefore, the difference in oscillation amplitude between the welding end point - and the welding start point (g) is expressed as The distance of any point from the welding start points is L
When n is assumed, the oscillation amplitude at the above arbitrary point is as follows. Here, if C・=direct use −・) (2), the oscillation amplitude at any point is W (1+ O+ −L
n)...=1).

In the constant calculation in Calculation 1, C1 is obtained using equation (6) and is temporarily stored in the storage unit (5). When the calculation process is finished, the control unit (4) continues to execute calculation (2). In calculation (2), first, the groove dimensions and welding speed setting data F for the welding start point - and welding end point (to) are read out from the storage unit (5).The groove dimensions are given as shown in Fig. 7. Therefore, the control section (4) can easily calculate the groove cross-sectional area at the welding start point (g) and the welding end point -, and let the calculation results be AI and A2, respectively.

In the case of the consumable electrode welding method, the weld 1 at any position in the welding direction is inversely proportional to the welding speed as long as the welding current value is constant. Since the amount of welding needs to be made proportional to the deterioration of the groove cross-sectional area as welding progresses, the welding speed at the welding end point (E) is p and A + . Therefore, the difference in welding speed between the welding end point - and the welding start point (g) is expressed by, and furthermore, the welding speed at an arbitrary point having a distance of Ln from the welding start command becomes 8Here, at the arbitrary point The welding speed is F (1+ 02 ・Ln) -...
(D) can be replaced.

In the constant calculation in calculation ■ (calculate C2 by formula 9,
Once stored in the storage unit (5), the control unit (4) finishes executing the pre-calculation and moves on to output control operation for external equipment.The control unit (4) also controls the welding speed and oscillation rate during welding. In addition to patterns, it is necessary to perform various controls such as welding current in real-time processing, and a management program called O8 (operating system) is required for this operation.
As for 8, some are commercially available, and their contents are irrelevant to the present invention, so I will omit the explanation. It shows the state of control.
Figure o is a flowchart regarding control of the oscillation pattern.

Of the output control operations, oscillation pattern control will first be explained. Note that FIG. 10 is a flowchart in which only oscillation-related control is arranged in chronological order, and it should be noted that in actual control, other tasks and 6 are processed in real time by the aforementioned O8. The data located at the midpoint of the oscillation amplitude is output from the control unit (4) to the 1)/A converter (7) for Y-axis control during the initialization operation (initialization) before the start of welding. , when the output data is larger than the data at the midpoint, the right side [one to welding, ! -''61)], and if you make it smaller, it will be on the left [
Welding torch 03 in the direction away from the welding joint 01)
move. .

After the welding start command is issued and calculation 1.11 is executed, the next preliminary calculation is performed in the oscillation control task. That is, the oscillation rate movement amount ΔW per certain time is calculated from the oscillation rate ffi width of the setting data and the -4 syllate traverse time. The certain time mentioned here is the execution time interval until the execution of the oscillation control task or the 9th execution. Therefore, if ΔW is added or subtracted from the output data for each execution time interval, welding is performed by the Y-axis drive servo system. The torch can be moved to the right or left at a predetermined speed7.The execution time interval is 20 m5 in this example8.
In Fig. 1θ, at the same time as welding starts, the current X @ pulse value is read in the process qO, the oscillation amplitude is calculated using the above formula (to), and the Y @ position of the right end of the oscillation to be reached is determined from the result. Further, in (c), the current Y-axis position is read from the A/D converter shown in Figure 1 and compared with the Y-axis position to be reached. If it is determined in (c) that the oscillation rate has not yet been reached, ΔW is added to the current Y-axis output data and outputted in process 0, and the process returns to process q0. Proceed to.

In process f4, the timer is turned on according to the set value of the oscillation stop time. Furthermore, in process (c), the current X-axis pulse value is read, the oscillation amplitude is calculated using the above-mentioned (BJ formula), and the Y-axis position of the right end of the oscillation to be reached is determined from the result in the same way as process G'0. In Q0, the value is output as Y-axis output data, and even during the oscillation stop time, the welding torch 03 is controlled to follow the change in groove width.In judgment (c), the timer Ib of the oscillation stop time is determined. However, if the time is still within the time, return to process (c).If time is up, proceed to process t1 fathom, but process 4 or A is a control to move the welding torch α3 aiming at the left end of the oscillation rate. , the control method is described above, and the single processing fQ-(
Since it is basically the same as (a) and overlaps, the explanation will be omitted.

In addition, in process -, (c), @, the current X-axis pulse value is always compared with the welding end point ω0) By controlling the output of the oscillation pattern as described above, as shown in Fig. 7(b), the oscillation is performed in accordance with the welding distance over the entire ζ welding distance and the groove width change. The pattern can be changed. Next, we will explain the welding speed control operation ζ. The welding speed at any point in the welding direction is expressed by the formula Q),
During welding, the control unit (4) reads the current X-axis pulse in the welding speed control task, calculates the welding speed based on the current groove cross-sectional area based on the formula 0, and converts the D/A conversion converter α. On the other hand, the output is performed through the input/output circuit (7), and as a result, as shown in Fig. 7 (a), it is possible to change the welding speed according to the groove cross-sectional area and the welding distance is 1. .

In the above embodiments, only the so-called 1-shaped groove' is described, but the purpose can be achieved using the same concept for other groove shapes such as the V-shaped groove. [Effects of the Invention] This invention is constructed as described above, and even when the groove widths at both ends of the welding location are different, part of the welding conditions during welding can be changed as the groove width changes as welding progresses, or By automatically correcting according to changes in the groove cross-sectional area and controlling the amount of welding, it is possible to obtain a uniform reinforcement height, eliminate the need for repair welding, and achieve unmanned work. effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 to Fig. 10 show diagrams according to an embodiment of the present invention, Fig. 1 is a process diagram, and Fig. 2 is a plane showing the positional relationship between the welding plate and the workpiece to be welded. Fig. 8 is a side view thereof, Fig. 4 is a front view showing the operation section, Fig. 5 shows the groove dimension measurement location, Fig. 1, Fig. 6 is an internal configuration diagram of the storage section, Fig. 7 are the welding speed and oscillation pattern control chart factors, Figure 8 is the oscillation pre-calculation flowchart, and Figure 9 is the oscillation pattern pre-calculation flowchart.
The figure is a welding speed pre-calculation flowchart, Figure 10 is an oscillation pattern control flowchart), Figure 11 is a professional diagram of a conventional device, and Figures 12(a) and (b) are examples of objects to be welded. They are a plan view and a front view. (1) is the workpiece to be welded, (2) is the welding groove, (6) is the condition setting section, ■ is the control device, C11) is the welding / lid, and ni) is the operation section. It is. In the figures, the same reference numerals indicate the same or equivalent parts.

Claims (3)

[Claims] (1) In an automatic welding device that has a self-propelled welding head with an oscillation function and performs arc welding on a workpiece that has a welding groove, predetermined welding conditions at a specific position of the workpiece are A means for inputting settings, and each intersection point related to the welding groove at both ends of the workpiece, which is necessary to correct a part of the welding conditions according to a change in the groove width or a change in the groove cross-sectional area of the workpiece. , and a means for teaching the positions of both ends of the welding part of the workpiece, and a change in the groove width or a change in the groove cross-sectional area of the workpiece based on the setting input and information taught by each of the above means. An automatic welding device comprising means for automatically correcting a part of welding conditions according to the conditions. (2) The automatic welding apparatus according to claim 1, wherein the specific position of the object to be welded is a welding start point. (3) The automatic welding apparatus according to claim 1 or 2, wherein part of the welding conditions is an oscillation width and a welding current.