JPS5939232B2 - Fillet end corner welding method and device - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is designed to uniformly form fillet end corners formed on both upper and lower sides of a vertical fillet, and to stabilize and increase welding strength. The present invention relates to a welding method capable of automatically rotating welding in a held state, and a configuration of a welding robot for implementing the method.

[Conventional technology]

Due to recent advances in welding technology, in the frame assembly process in the construction industry and the hull frame assembly process in shipbuilding factories,
It is well known that most connections are made by welding instead of conventional riveting and the like.

Particularly in the shipbuilding industry, where there are many opportunities to construct large ships such as tankers in the hundreds of thousands of tons class, it is natural that the number of welding points increases both qualitatively and quantitatively. However, there are undesirable problems such as long construction periods, increased labor costs, soaring ship prices, and delays in delivery, so the introduction of automatic welding work is gradually being actively carried out in various fields. It is well known.

Now, if we consider the case where the hull skeleton is assembled by welding, the hull is once assembled for each divided block and then joined together on the dock.
As shown in the figure and FIG. 2, the longitudinal member L and the transformer member T arranged in the vertical direction are assembled orthogonally,
A method of welding a skin plate or an upper deck to the outer periphery is adopted, and the work of linearly welding the inner corners of the perpendicular parts [the parts shown by small black dots in Figure 1], that is, fillet welding, is adopted. , which occupies particular importance.

This fillet welding is difficult to work with when automating welding, and it is usually preferable to build up the weld metal at the inner corner so that the cross section forms a right isosceles triangle. If the shape is an equilateral triangle, the strength will be extremely reduced, and various problems such as peeling of welded parts will occur after delivery to the ship.

However, the overlay was finished in the shape of a right-angled isosceles triangle, and
Welding so that the penetration depth reaches a predetermined positive value requires correcting the facing angle of the welding gun and the welding conditions, which is a difficult task even for highly skilled workers.
Furthermore, even among fillet welds, round welding requires more skill and man-hours than vertical corner welding, and under the current circumstances, it is even more difficult to perform this completely by automatic welding. Conventionally, fully automatic fillet welding equipment that can meet such demands has not been provided, and the current situation is that we still rely on semi-automated equipment that requires supervision by skilled personnel.

[Problem that the invention seeks to solve]

In view of the above-mentioned facts, the present invention is capable of automatically processing the welding part without using any manual labor, and of course maintains the strength of the welded part, and also allows the weld metal to be rotated and evenly deposited on the fillet part. The present invention was developed to provide a new method for turning welding of fillet end corners and a device for implementing the method, which can achieve a beautiful finish at the same time. It is an object of the invention to accomplish this simply and reliably by.

[Means for solving problems]

Therefore, the present invention is a first invention, which is a rotary welding method, which detects the vertical ridgeline of the fillet part and directs the welding torch to the tip by a detection signal from a sensor that directs the detection axis to the vertical ridgeline. A welding robot is used to control the welding arm to be oriented in the direction of the bisector of the included angle of the fillet with respect to the vertical ridgeline. When welding a portion, the welding arm is directed from the horizontal direction toward the lower end or upper end at the beginning or after the vertical corner welding process adjacent to the lower end or upper end of the vertical ridge line, and The position of the welding arm is memorized for each operating axis, and then the welding arm is moved from the position by a predetermined distance calculated in advance to a lowered position at the lower end and a raised position at the upper end, and the end of the vertical ridge line. After moving the welding torch upward or downward so as to be able to direct the welding torch obliquely to the part, while directing the welding torch parallel to the horizontal part continuing to the end of the vertical ridge line,
It is characterized by moving the welding arm.

In addition, the present invention is a second invention, which is a device for performing rotary welding, which has a base shaft that can extend and contract in the vertical direction, a movable base that can be fixed at a desired position, and a work direction. a welding torch, extending between the base of the welding torch and the base shaft, horizontal translation and rotation of the welding torch;
Detects the fillet formed by the intersection of two vertical flat plates and a welding arm supported so that it can move forward and backward, move up and down in the vertical direction, and swing in the horizontal direction about the base. a fillet detection body including a sensor that can pivot its detection axis toward the fillet and is rotatably supported on a welding arm;
A pair of contact type length measuring instruments are provided in relation to the welding arm and the fillet detecting body 14, and are provided in relation to a pair of contact type length measuring devices which extend axisymmetrically on both sides of the welding arm in the horizontal direction. It is composed of a declination signal generator that emits a signal corresponding to the deviation, and a control circuit that controls each movement of parallel movement, forward and backward movements, telescopic movement, turning movement, rocking movement, and elevation and depression movement. teeth,
Approach angle/interval control in which the welding arm is moved in parallel based on the difference between the two signals so that both signals from the pair of contact type length measuring devices match a predetermined value, and moved forward or backward based on the difference from the predetermined value. a circuit section, a direction control circuit section that pivots the welding arm to align with the fillet detecting object based on a signal from the declination signal generator, and a direction control circuit section that swings the welding torch at a speed and amplitude suitable for welding conditions. The swing control circuit detects the end of the vertical ridgeline of the fillet, and uses the expansion and contraction movement of the base shaft and the elevation of the welding torch to direct the welding torch from diagonally outside and in front of the corner of the fillet by a set distance. a fillet end corner direction control circuit for moving the welding arm forward, backward, and parallel; and welding along the horizontal direction welding portion of the fillet end corner determined by the thickness of the vertical plate. The torch is configured to have a combined movement of parallel movement and advance/retreat to move the torch, and a turning movement control circuit section for extending and retracting the base shaft along the vertical ridge line, and the corner The fillet corner is detected by the fillet detector, and it is possible to automatically perform rotary welding of vertical corner portions and horizontal portions adjacent to the fillet corner. .

〔Example〕

Hereinafter, embodiments of the present invention will be clarified by the following description based on the accompanying drawings. FIG. 4 is a perspective view of the main body structure of a welding robot according to an apparatus for implementing the method of the present invention.
The welding robot 1 includes a movable base 2 that is placed on a guide mechanism such as a track and fixed at a desired position, and is pivotally supported on the base 2.
A base shaft 3 that is erected in a direction parallel to a vertical ridge line 27 of a fillet portion 26 (to be described later), that is, in a vertical direction, and is capable of expanding and contracting Z in this direction, and a direction perpendicular to the base shaft 3 (in the horizontal direction in this example). A welding arm 5 is installed horizontally on the shaft, and is capable of moving forward and backward in the longitudinal direction of its axis, and capable of parallel movement X and rotation R in the horizontal direction perpendicular to the axis. A welding torch 6 is pivotally supported so as to be able to swing W in the horizontal direction and move up and down in the vertical direction, and is disposed parallel to the welding arm 5 above the welding arm 5, and It is attached to the base shaft 3 so that it can freely rotate in parallel with the welding arm 5, and a sensor 16 for detecting a fillet part is attached to the tip of the extensible shaft 15, so that it can freely rotate in parallel to the rotation of the shaft 15. Fillet detecting body (hereinafter abbreviated as detecting body) formed by pivotally supporting 1
It is composed of 4.

The welding robot 1 having the above-mentioned skeleton structure has a straight line formed by two vertical flat plates 25, 25 that intersect at a predetermined intersecting angle [θ1], for example, at a right angle, and are arranged to have a common orthogonal cross-horizontal plane. After the movable base 2 is moved to a position near the fillet 26 of
By making a compound movement of
With the welding torch 6, for example under argon electric welding,
The fillet portion 26 may be welded. In addition,
The welding torch 6 is moved from above to below along the vertical ridge line 27 of the fillet 26 by causing the base shaft 3 to expand and contract while being swung at a slight angle W in the horizontal direction by the weeping device 13. Conversely, fillet welding can be performed sequentially.

The welding arm 5 has contact length measuring instruments 7-1, 7- on both sides slightly behind the welding torch 6 which is provided at the tip of the welding arm 5.
2 is at a predetermined angle sandwiching the welding arm 5, and the welding arm 5
It is provided so as to extend horizontally so as to point toward the tip of the tube.

These contact type length measuring instruments 7-1 and 7-2 are capable of emitting electrical signals having positive and negative polarities corresponding to the amount of displacement when the sensitive end is mechanically displaced with respect to a certain reference position. You can use any type of length measuring mechanism, but
In this example, a differential transformer is used so that displacement of the movable iron core appears as a change in terminal voltage.

Then, both length measuring instruments 71 and 7-2 match the angle (5) formed by each axis with the intersection angle [θ,] of the fillet 26, as shown in FIG. , and the angle [2α
] is stretched so as to be a complementary angle [180-θ,] to the above-mentioned intersecting angle [θ,].

On the other hand, the sensor 16 provided on the detection body 14
Various forms are available, such as a light quantity-to-electrical quantity converter that can detect the vertical ridge line 27 as a difference in brightness from other parts and convert it into an electrical signal, and an air pressure-to-electrical quantity converter that can detect a change in pressure. However, in this example, a contact type sensor is used, and its structure is such that the center of the bottom part is rotatably supported on the tip of the arm 15, or as shown in FIG. A roller 18 is rotatably attached to each corner of an isosceles triangular substrate 17, which is rotatably supported by a shaft extending from an apex corner sandwiched between equilateral sides. A counterbalance spring 2 is installed so that the roller 18 that has landed is held at the leading edge of the arm 15 in a normal state where no mechanical force is applied.
0,20, and the triangular board 17
Touch switches 19, 19 such as micro switches are respectively attached to the arm 15 in a line-symmetric manner on both oblique sides of the arm 15, and when the flat plate contacts the tip roller 18 and the side rollers 18 in a common tangent , the touch switch 19, 19
For example, the switch is switched from off to on. In the present invention, the sensor 16 may be of a non-contact type as long as it is a mechanism capable of detecting the fillet 26 and directing its detection axis toward the fillet 26; 16 may be directly pivotally supported on the welding arm 5. The detecting body 14 further has a declination signal generator 21 fixed to the vicinity of the pivot axis with the welding arm 5 as a reference line, and in this example, a potentiometer is used as an element. The deflection angle with respect to the welding arm 5 can be converted into an electric signal having positive and negative polarity, and the resistance value is changed in relation to the movement of the detection body 14.

The configuration of each part of the welding robot 1 is as described above,
And the robot mouth is P. T. P.C. POIN-TTOP
OINT] Formed so that automatic fillet welding work can be performed by switching between the control method and the release mode control method, or by using a combined control circuit to follow the fillet 26 and in accordance with a preset procedure. has been done.

The control circuit controls the welding arm 5 so that both signals from the pair of contact length measuring devices 7-1 and 7-2 match predetermined values, as shown in FIG.

The welding arm 5 is aligned with the detection object 14 by the signal from the approach angle/spacing control circuit, which causes parallel movement X based on the difference between the two signals, and advances or retreats Y based on the difference from the predetermined value, and the declination signal generator 21. A directional control circuit unit that rotates the welding torch 6 to make it pivot R, a swing control circuit unit that swings the welding torch 6 at a speed and amplitude that match the welding conditions, and appropriately detects the end of the vertical ridge line 27 of the fillet portion 26. In order to direct the welding torch 6 from the diagonally outside front of the fillet end corner 28, the base shaft 3 expands and contracts Z and the welding torch 6
A fillet end corner direction control circuit unit that performs the elevation and elevation movement S of the welding arm 5 and the forward and backward movement Y and parallel movement X of the welding arm 5, and the fillet end angle determined by the thickness of the vertical flat plates 25, 25. Part 28
a rotational movement control circuit unit capable of moving the welding torch 6 according to the depth dimension of the welding torch 6, performing a combined movement of parallel movement They each have their own. Note that the above device has a welding arm 5.
Although a mechanism is shown in which the detection body 14 and the detection body 14 are provided separately, a structure in which both the detection body 14 and the detection body 14 are integrated with their axial directions aligned may also be used. Next, the operation of the welding robot 1 will be explained in the case of fillet welding of a hull frame assembly with reference to Figures 3 to 10. After that, welding conditions such as the plate thickness of the transformer member T, the welding leg length, the welding speed of the welding torch 6 and the welding scrap tension of the fillet 26, the welding width and speed of the welding torch 6, and the vertical movement speed of the welding torch 6 are controlled. Set in the memory section of the circuit (mouth).

Then, the welding robot opening is installed along the transformer member T (c), and the welding robot is moved in a direction parallel to the transformer member T [left and right in Fig. 1, and when the robot 1 reaches the front lower part of the longitudinal member L, the limit switch, etc. The presence of the longitudinal member L is detected by an appropriate mechanism and the traveling is stopped (d)
. At this position, the rough positioning of the welding arm 5 is completed, and when it reaches the area where horizontal and plane tracing control is possible, the base axis 5
is operated on the extension side of the extension/contraction movement Z, and when the horizontal welding arm 5 reaches a slightly higher level than the lower side of the longitudinal member L, the extension operation is stopped (e). In this state, the rough positioning of the base shaft 3 is completed, and the P.O. T. When the P control is completed, the next stage of copying operation can be started.

Next, a copying operation start command is issued, and compressed air at a predetermined pressure is sent to the arm 15, for example, a pneumatic cylinder, and the detection body 14 is moved forward. The cylinder 15 is designed so that the pressure inside the cylinder can always be maintained at the predetermined pressure regardless of the presence or absence of external pressure by means of a relief valve or the like installed in the pneumatic line.

In this way, the tip of the detection body 14 moves forward toward the fillet 26, but here, since the shaft end is not correctly oriented toward the fillet 26, one of the vertical flat plates 25, that is, the longitudinal plate forming the fillet, moves forward. The most advanced roller 18 comes into contact with the member L or the transformer member T first, and then the rotatable triangular base plate 17 receives a turning force, and the rear roller 18 subsequently comes into contact with it, thus creating a freely rotating detection object. 14 is guided by the triangular base plate 17 sliding along the longitudinal member L or transformer member T, approaches the fillet part 26 while turning, and finally the most advanced roller 1
8 touches the fillet part 26, both touch switches 1
9 and 19 operate, and the extension stops [the above operation is the seventh
As shown in Figures I to B.

In this state, the axis of the detection object 14 is correctly directed toward the fillet 26, and the detection of the direction of the fillet 26 is completed (f), but the relative rotation angles of the detection object 14 and the welding arm 5 are different. This declination is detected as an electrical displacement by the potentiometer 21 serving as the declination signal generator 21, and the direction control circuit section sends the welding arm 5 using the displacement signal as a command.
A rotation output is issued to the rotation motor 8 to cause the welding arm 5 to perform a rotation operation, and the rough direction determination of the welding arm 5 ends when it is aligned with the detection body 14 .

Here, since the contact type length measuring devices 7-1 and 7-2 are in a free state where they do not come into contact with the vertical flat plates L and T, the approach angle/distance control circuit is activated and the welding arm 5 is moved to extend. A command in the Y direction is issued, and the signal S from one length measuring device 7-1
1 matches the set value.

Around this time, the positive and negative signals from the length measuring devices 7-1 and 7-2
The signals S, S2 having negative polarity are compared and a corrective action is given to the X-axis 1 drive system to cause the welding arm 5 to move in parallel until the ratio k of both signals becomes 1 and becomes equal.

When the parallel movement of the welding arm 5 is controlled in this way, the axes of the arm 5 and the detection body 14 are no longer aligned, so the command signal from the potentiometer 21 moves the R-axis
A corrective action is performed on the drive system, and the welding arm 5 is directed toward the fillet portion 26 at a predetermined approach angle, that is, 45 a in the direction of the equisector, due to the above-mentioned combined movement of the parallel movement X and the rotation movement R. death,
Then, the positioning control in which the welding torches 6 are faced to each other at the set separation distance is completed.

Note that it is natural that the approach angle [θ2] when the welding arm 5 is directed toward the fillet 26 is a percentage of the intersection angle [toward] of the fillet 26, as shown in Fig. 5. As shown in FIG. , S2 are selected so that the relationship S1-S2 is established, it goes without saying that the approach angle [''←] in the direction of the equal dividing line will correctly point the welding arm 5 toward the fillet 26. , on the other hand, the triangular substrate 17 of the sensor 16 in the detection body 14 also has an apex angle equal to the intersection angle [θ1]
It is formed into an isosceles triangle that approximately matches the .

In this way, the approach angle [θ2] can be determined. Next, to determine the workpiece tension D between the tip of the welding torch 6 and the fillet 26, the length measuring devices 7-1 and 7-2 are used. Length from the installation base point (0) to the tip of welding torch 6 (l)
In relation to this, the set lengths of both length measuring devices 71, 7-2 may be selected to appropriate values, and 41-no VlP-'≦
If the setting signals S, , S2 are determined so that the relationship \--'z holds true, directional control can be performed so that the work piece tension becomes D in the direction of equally dividing the corner of the fillet.

In this way, the approach angle/separation control is completed, and the base shaft 3 is lowered (nu).
As the length measuring instruments 7-1 and 7-2 move, the fillet end corner 28
is detected (d), so at this point, the position information of each axis is memorized, the descent is stopped (w), and the position is further moved a certain distance from this position Z (the position indicated by 1 in Figure 10 A) as a reference. The values of each axis R, X, Y, Z, and S at the position to be lowered are stored in the storage section (W).

The memorized position is the position of the welding torch 6 as described later.
When the welding torch 6 is raised and lowered by a predetermined angle of elevation and depression S, the welding torch 6
It is a requirement that the tip of the workpiece be in a position where it can be directed toward the fillet end corner 28 with a predetermined workpiece tension D, and
In Fig. 10A, the mouth is in the position shown by 3. The robot 1, which has memorized the positions in each direction X, Y, Z, and R as described above, is moved as shown in FIG. Move backward to position Y (g), then lower the base shaft 3 to the above-mentioned predetermined lowering position [position indicated by 3 above] (y)
After that, the welding arm 5 is moved forward and backward (forward) Y, parallel movement X, and rotational movement R to the position shown by 4 in FIG. When raised by a predetermined angle (evening), the torch 6 correctly points its tip toward the fillet end corner 28 from diagonally downward and forward.

Therefore, welding that meets the welding conditions is started, and the welding arm 5 is moved in that direction by the thickness of the transformer member T ((d), but this movement is performed at an approach angle [-1 ] is 45, the X-axis and Y-axis are moved simultaneously at a speed ratio of 1:1, and the Y-axis and X-axis are moved at a speed ratio generally determined by the approach angle, and this is repeated several times. When the number reaches the number (S), the CA is returned to the above-mentioned storage position and the CA is temporarily stopped.

When rotary welding of the lower surface part, that is, welding of the vertical corner part and the horizontal part adjacent to the fillet end corner part 28, is completed, each axis X, Y, Z, and S is operated to align the vertical ridge line 27 of the fillet part 26.
With respect to the lowest end, return the welding torch 6 to the initial position where it is directed horizontally from the direction of the bisector of the included angle [θ1] [N].
After once stopping the movement of each axis, the X-axis and Y-axis are switched to the copying mode, and then the welding torch 6 is given a swing W while the base shaft 3 is extended and contracted (raised) at a constant speed. 5 is an FP that rises while following the vertical ridgeline 27 and performs welding while sweeping the welding torch 6.
).

When this weeping welding reaches the uppermost end of the vertical ridge line 27, it is completed by a command (A) from the sensor 16 that detects the uppermost end, and the welding robot 1 temporarily stops at this position (5).

The subsequent movement is carried out in the same manner as the downward welding described in the first operation, except that the welding torch moves downward rather than upward and points toward the vicinity of the fillet end corner 28 from diagonally upward and forward. The only difference is that the other aspects are the same as the bottom round welding.

In this way, when rotation welding and vertical corner welding are completed for one vertical ridge line 2T, each axis is returned to the initial position, the movable base 2 is moved to the next section, welding is performed again in the same manner, and welding is repeated in sequence. When all welding is completed in the first row along the transformer member T), the welding is then moved to the adjacent second row,
Repeat welding.

It should be noted that the welding procedure is not the only one, as in the example above, in which one fillet 26 is lowered, vertically cornered, and then moved over to the next fillet. Variations such as welding the bottom and vertical corners in the forward stroke and then welding the top in the backward stroke are possible, and can be done at any time by storing sequential commands in the robot control circuit in advance Can be changed.

〔Effect of the invention〕

As described above, when round-welding the fillet end corner 28, the present invention first stores the position of the end corner 28 in the welding robot 1, and then adjusts the welding torch 6 according to the dimensions calculated in advance from the stored position. Since the robot moves the welding torch 6 toward the fillet end corner 28 by moving the welding torch 6 to the outside in the vertical direction and directionally approaches the fillet end corner 28 from an obliquely outward direction, rotation welding of the fillet end corner 28 is performed. Even if the position of the fillet end corner 28 is different, the position is checked each time and welded by turning.
There is no positional shift and it is possible to weld in the correct location.

Therefore, when automatically performing fillet welding of a lattice frame such as in the hull frame framework process, even if the heights of the fillet end corners 28 have slight level differences, it is possible to Since welding is performed after detecting the welding process, it is possible to reliably perform round welding and subsequent vertical corner welding in the automatic welding process.

Furthermore, in the device of the present invention, the detection body 14 that detects the fillet 26 and the welding torch 6 that works on the fillet 26 are formed as separate mechanisms, so the detection body 14 has a lightweight structure, is light and lightweight. The welding torch 6 can be actuated by force, the target fillet 26 can be detected quickly and accurately, and the welding torch 6 can be quickly directed to the fillet 26 that is the object of direction control.

Furthermore, the drive mechanism for aligning the axis of the welding torch 6 with the detection body 14 requires only the rotation R movement, so the structure is simple and control is easy. Control for pointing can be done by making the welding torch 6 perform forward and backward movement Y and parallel movement X using the contact type length measuring devices 71 and 7-2 as detection ends, so no improvements are made to the drive system of conventional robots. It can be applied without adding anything, and has a wide range of adaptability. In addition, the adjustment of the workpiece tension D of the welding torch 6 can be made by simply changing the set length of the length measuring devices 7-1 and 7-2, so handling is extremely easy, and the servo control system is also a simple circuit. It has good and versatile effects.

Furthermore, since the present invention allows the welding torch 6 to be directed close to the fillet 25 from the most appropriate direction, the positioning of the robot that performs precision processing such as rotary welding can be performed more reliably and easily. This is a rotary welding method and device that has greatly contributed to the industry by streamlining work and reducing the number of personnel required.

[Brief explanation of the drawing]

1 and 2 are a schematic plan view and a schematic front view of a lattice frame welding apparatus according to the method of the present invention, and FIG. 3 is a partially enlarged perspective view of the lattice frame shown in FIG. FIG. 4 is a perspective view of a welding robot according to the method of the present invention, FIG. 5 is a plan view illustrating the operating mode of the device shown in FIG. 4, and FIG. 6 is an example of the device used to implement the method of the present invention. A schematic structural diagram of the sensor, FIGS. 7A to 7E are plan views sequentially explaining the operation mode of this sensor, and FIGS. 8 and 9 are block diagrams and flow lines of a control circuit according to an example of the device of the present invention. Figure 10 A, C]!
FIG. 6 is a plan view and a front view showing how the welding torch operates during round welding. 1... Welding robot, 2... Moving base, 3... Basic axis, 4... Detection axis, 5...
...Welding arm, 6...Welding torch, 7-1, 7-2...Contact length measuring device, 14...
- Fillet detection object, 16... sensor, 21...
... Declination signal generator, 25 ... Vertical flat plate, 2
6... Fillet part, 27... Vertical ridge line of fillet part, 28... Fillet end corner, R... Turning movement, S. ...Elevation, W... Rocking, X
...Parallel movement, Y...Advance/return, Z...
...Extension and contraction movement.

Claims (1)

[Claims] 1. Welding with a welding torch 6 at the tip by a detection signal from a sensor 16 that detects a vertical ridgeline 27 of a fillet 26 and directs its detection axis 4 toward the vertical ridgeline 27. The arm 5 is placed at an angle of 2 of the included angle of the fillet 26 with respect to the vertical ridge line 27.
When welding the vertical corner portion and the horizontal portion adjacent to the fillet end corner portion 28 using the welding robot 1 which is controlled to direct from the direction of the equal dividing line, the vertical ridge line 27
At the end of or after welding the vertical corner adjacent to the lower end or upper end of the welding arm 5, the welding arm 5 is directed from the horizontal direction toward the lower end or the upper end, and the position of the welding arm 5 at that time is determined for each operating axis. Then, the welding arm 5 is moved from the position by a predetermined distance calculated in advance to a lowered position at the lower end and a raised position at the upper end, and the welding arm 5 is moved along the vertical ridge line 2.
After moving the welding torch 6 up and down so that it can be directed diagonally toward the end of the vertical ridge line 27, welding is performed while the welding torch 6 is directed parallel to the horizontal portion following the end of the vertical ridge line 27. A rotary welding method for a fillet end corner, which is characterized by moving an arm 5. 2. A movable base 2 on which a base shaft 3 capable of vertical expansion and contraction Z is erected and can be fixed at a desired position, a welding torch 6 having work directionality, and a base portion of the welding torch 6 and the base shaft 3. In between, the welding torch 6 can be moved horizontally in parallel (X), rotated (R), moved back and forth (Y), raised and lowered in the vertical direction (S), and rocked in the horizontal direction (W) with the base as the center of rotation. The welding arm 5 is equipped with a sensor 16 capable of detecting a fillet 26 formed by intersecting the welding arm 5 and the two vertical flat plates 25, 25 and directing its detection axis 4 to the fillet 26. A fillet detecting body 14 is pivotably supported on the welding arm 5 and is directed toward the welding torch 6 from an appropriate position of the welding arm 5.
A pair of contact type length measuring devices 7-_1 and 7-_2 extend symmetrically on both sides of the welding arm 5 in the horizontal direction, and the welding arm 5 and the fillet detection body 14 are related to each other. is provided,
A declination signal generator 21 that emits a signal corresponding to the turning angle deviation between both 5 and 14, parallel movement X, forward/backward movement Y, and telescopic movement Z
, a control circuit that controls the respective movements of rotation R, rocking W, and elevation and elevation S, and the control circuit includes a control circuit that controls the movements of the pair of contact length measuring devices 7-_1 and 7-_2. an approach angle/spacing control circuit unit that moves the welding arm 5 in parallel (X) based on the difference between the two signals so that both signals match a predetermined value, and moves the welding arm (5) forward/backward (Y) based on the difference from the predetermined value; A directional control circuit unit that uses a signal from the generator 21 to rotate the welding arm 5 to align it with the fillet detector 14, and a oscillation unit that oscillates the welding torch 6 at a speed and amplitude that match the welding conditions. detecting the dynamic control circuit section and the end of the vertical ridge line 27 of the fillet section 26;
In order to direct the welding torch 6 from the diagonally outer front at a set distance from the fillet end corner 28, the expansion and contraction movement Z of the base shaft 3, the vertical movement S of the welding torch 6, and the forward and backward movement Y and parallel movement X of the welding arm 5 are performed. The welding torch 6 can be moved along the horizontal direction welding portion of the fillet end corner 28 determined by the thickness of the vertical flat plates 25 and 25. Performs a combined movement of parallel movement X and forward/backward movement Y,
and rotational movement control circuit parts that extend and retract Z the base shaft 3 along the vertical ridge line 27, and
8 by the fillet detector 14, and the vertical corner portion and the horizontal portion adjacent to the fillet end corner portion 28 can be automatically welded. Welding equipment.