JPS6129825B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a new groove tracing device for a welding device, and in particular, the present invention relates to a groove tracing device for a new welding device, and in particular, the present invention relates to a groove tracing device for a new welding device, and in particular, a torch is pressed against one groove wall surface and a welding wire outlet is placed on the groove wall surface. The present invention relates to a groove tracing device of a welding apparatus that can carry out proper automatic tracing welding on a wide groove that requires two passes by tracing along the groove.

[Conventional technology]

A submerged arc welding device is known as an automatic welding device. As shown in FIG. 1, this welding device has a carriage 2 that is self-propelled along a track 1, and a torch 5 supported on the carriage 2 facing a groove 4 formed between base materials 3. is provided. A welding wire 7 is supplied to this torch 5 from a wire reel 6 also provided on the carriage 2, and this wire 7 is sequentially led out into the groove groove 4 from an outlet 8 formed at the tip of the torch 5. It is designed to be melted by an arc. 9
10 is a hopper containing sandy flux covering the arc, and 10 is a control device. Therefore, the weld line 1 formed along the longitudinal direction within the groove 4 of the track 1
This means that it can be moved along the top of 1.

[Problem that the invention seeks to solve]

However, in conventional welding equipment, although the position of the torch 5 can be adjusted, it is fixedly attached to the carriage 2, so that the torch 5 may not be aligned with the weld line 1 due to an error in the placement of the track 1. The problem was that it could come off or be tilted with respect to the center line of the groove, making it difficult to weld accurately.

In addition, when the groove width becomes wide, groove center tracing (single-layer, one-pass welding) causes poor unraveling on the left and right sides, so one-layer, two-pass welding is required. In this case, the torch is attached to one groove wall. It is necessary to maintain a certain distance and run parallel to the vehicle, but there was no means to effectively implement this.

Therefore, in view of the problems with conventional welding devices, the present inventors have devised the present invention in order to effectively solve the problems.

[Purpose of the invention]

Therefore, it is an object of the present invention to develop a welding device that can carry out appropriate automatic tracing welding for a wide groove width by keeping the torch at an appropriate position relative to the groove wall surface while tracing the groove. To provide a copying device.

[Summary of the invention]

The present invention is constructed as follows to achieve the above object. A torch holder attached to a table that reciprocates on a carriage is provided on the upper part of the torch, and the torch is swingable in the width direction of the groove and is held rotatably around its axis. In this way, a flat torch member is provided at the lower part of the held torch, and this torch member has a welding wire outlet formed at the center of the tip and a welding wire outlet that extends from the outlet along the longitudinal direction of the groove. It consists of a guide part extending in the running direction and the backward direction, and is adapted to be inserted into the bevel groove. The upper part of the torch is provided with a torch pressing and urging means that preloads the torch and swings it in one direction to press the torch member against one of the groove walls.The torch pressing and urging means biases the torch member. Even if the plane is not parallel to the groove wall surface and either the running direction guide section or the backward direction guide section is pressed against the groove wall surface first, this will cause the torch to rotate, causing both guide sections to rotate. are both in contact with the groove wall surface. Thereby, the torch pressing biasing means has a function of positioning the torch member parallel to one groove wall surface. Further, the torch is also equipped with a torch posture control means that detects the inclination of the torch and corrects the inclination by moving the table based on this detection, so that the torch is aligned parallel to the perpendicular line drawn on the welding line of the bevel groove or at a predetermined angle. It is constructed so that the welding wire outlet is always faced in a fixed position by being raised upright.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a groove tracing device for a welding apparatus according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 2 showing one embodiment, 12 is the orbit 1
A mounting portion 14 is mounted on the carriage 12 via a table 15. This table 15 is provided so as to be able to reciprocate in a direction perpendicular to the traveling direction of the carriage 12 (in the left-right direction, which corresponds to the groove width direction in the drawing), and is driven by a motor 16. A screw rod 17 is suspended from the mounting portion 14, and a nut member 20 connected to a support arm 19 via a support plate 18 is screwed onto the screw rod 17. A motor 21 of the screw rod 17 is driven by a switch in an operation box 28, so that the nut member 20 can be moved up and down along the screw rod 17. A torch holder 22 is pivotally supported on the support arm 19 so as to be swingable in a direction (bevel width direction) intersecting the traveling direction of the carriage 12, and a torch member A is provided at the lower part of the torch holder 22. A torch 24 is vertically installed so as to be freely rotatable. The main parts of the present invention are the above-mentioned carriage 12 and table 1.
5. Torch member A, torch pressing biasing means B for preloading the torch 24 in the swinging direction, and torch attitude control means C for correcting the inclination of the torch 24. In addition, 2
9 is a base material, and 30 is a groove.

As shown in more detail in FIGS. 3 and 4, the torch member A has base materials 29, 29 butted against each other.
It is inserted into the groove 30 formed between them and has a shape that can be moved along the longitudinal direction of the groove 30, for example, a flat shape and a shape wider than the groove 30. In particular, the torch member A has a welding wire outlet 31 formed at the center of the tip, and a guide portion 32 extending from the outlet 31 in the longitudinal direction of the bevel groove 30 in the traveling direction and the backward direction. ,3
3. Each of the guide parts 32, 33 is provided with sliding members 39, 40 for smooth movement on the groove walls 36, 37, and in this embodiment, the sliding members 39, 40 are made of electrically insulating material. It is composed of abacus-shaped wheels. Moreover, the sliding members 39 and 40 are connected to the groove wall surface 37.
When pressed against the groove wall surface 37, the torch member A
It also has the function of maintaining a certain distance from the groove, and in order to make this distance variable depending on the groove width, it is detachably attached and replaceable. The welding wire outlet 31 is configured to sequentially lead out the welding wire 34 to be supplied from the guide hole passing through the torch 24 in the axial direction.

The torch pressing biasing means B simultaneously moves the running direction guide part 32 and the backward direction guide part 33 of the torch member A to one groove wall surface 37 (or 3) of the groove groove 30.
6) is provided on the torch holder 22 to be pressed. This torch pressing/biasing means B consists of, for example, an air cylinder 23, one end of which is freely connected to the upper end of the torch holder 22, and the other end fixed to the support plate 18, as shown in FIG. The torch 24 is configured to apply preload to the torch 22 and urge the torch 24 to swing to the left or right. Therefore,
The torch member 24 is always in the state shown in FIG. Moving. At the same time, since the welding wire outlet 31 is formed in the center of the torch member A, it moves along the groove wall 37 while maintaining a certain distance therefrom.

The torch attitude means C includes a detection device 25, a control circuit 27, and the motor 16. The detection device 25 detects the inclination of the torch 24 preloaded by the air cylinder 23, that is, the inclination of the torch 24 with respect to the perpendicular line L drawn on the welding line 35 of the groove groove 30.
It consists of limit switches provided at two places on the left and right above the torch 24 that protrudes further upwards. The torch holder 22. When the torch 24 is preloaded and swings clockwise, the right limit switch 25a is turned on by contact with the upper part of the torch, and when it swings counterclockwise, the left limit switch 25b is turned on to detect the displacement of the torch 24. In response to the detection outputs of the limit switches 25a and 25b, the control circuit 27 issues a signal to rotate the motor 16 in forward and reverse directions.
In other words, the right limit switch 25a is ON.
Then, the motor 16 is driven to move the table 15 to the left, and this movement causes the torch holder 22 connected to the table 15 to become the pivot point.
When the limit switch 25b on the left is turned on, the table 15 is moved to the right and the torch holder 22 is pushed out to the right. Note that when the torch 24 is hanging down, the motor 16 is turned off.

D is the torch elevating means, the current detection part and the operation box 2
8 and a vertical movement mechanism. The current detection unit detects the welding arc current, and the operation box 28 compares this current with a reference current set in advance to achieve the best penetration without undercutting, and the motor is rotated forward or reverse depending on the magnitude of both. The screw rod 17 is rotated by issuing a signal, and the torch 24 attached to the nut member 20 is moved up and down along the screw rod 17 along with this rotation. Therefore, when the welding arc current is smaller than the reference current, a signal is output from the operation box 28 to drive the motor 21 and screw rod 17.
This rotation lowers the nut member 20 to lower the torch 24, and conversely, when the welding arc current is greater than the reference current, the screw rod 1
7 is reversely rotated to raise the nut member 20 and pull up the torch 24. Note that when the currents match, the motor 21 is turned off.

The operation of the groove tracing device of the present welding apparatus having the above configuration will be described.

First, the torch member A at the lower part of the torch is cut into the bevel groove 30.
The air cylinder 23 is actuated either in the direction in which the rod extends or in the direction in which it retracts. As a result of this operation, the torch member A hits one of the groove wall surfaces 37 (or 36), rotates until both the traveling direction guide section 32 and the reverse direction guide section 33 come into contact, and is pressed against the groove wall surface 37. Meanwhile, the trajectory of the carriage 12 is moved and the torch 24
The torch 24 is adjusted so that it stands vertically while maintaining the preload of the air cylinder 23, and the running direction of the torch 24 is parallel to the welding line. Then, when the power for the arc is turned on and the carriage 12 is run, the torch member A is in a state where the running direction guide part 32 and the backward direction guide part 33 are pressed against one of the groove wall surfaces 37 of the groove 30. It will move within the groove 30. In this case, each guide part 32, 3
The torch 24 can run smoothly by the sliding members 39 and 40 provided at the torch 24. Further, both groove wall surfaces 36 and 37 are substantially straight, and since the torch member A slides while keeping a certain distance from the groove wall surface 37 determined by the size of the sliding members 39 and 40, the welding line 37 is always It is also parallel to especially,
By providing the guide portions 32 and 33 at the front and rear, the torch member A is different from the case where there is only one torch member A, and the groove wall surface 37
Since the welding wire outlet 31 is formed in the center of the torch member S, the wall distance can be averaged even if there is a wall step or the like.

Here, if the track 13 is not arranged parallel to the welding line 35, or if the groove 30 is undulating or curved, the torch 24 will be preloaded by the air cylinder 23. Therefore, the torch member A does not separate from the groove wall surface 37, and the distance from the groove wall surface 37 remains unchanged, but since the pressing force against the groove wall surface 37 changes, it will tilt. Due to this inclination of the torch 24, the orientation of the welding wire outlet 31, which was initially parallel to the perpendicular line drawn on the welding line of the groove groove 30, changes and deviates from its normal position.

However, the inclination of the torch 24 is immediately detected including the direction of inclination by the limit switches 25a and 25b, and the table 15 is reciprocated in a direction based on the information via the control circuit 27. This movement pulls in or pushes out the torch holder 22 from the line of the bevel groove 30, so the torch holder 22 connected to the torch holder 22
4 is a torch member A restrained within the groove 30;
The groove is erected parallel to the center line of the groove, and the inclination is corrected. Therefore, the welding wire outlet 31 is opened by the torch member A.
is always a certain distance away from one of the groove wall surfaces 37 and the direction of the outlet port 31 is also constant, so that smooth running of the torch 24 and the torch member A following the groove wall surface 37 can be guaranteed. In particular, when the torch 24 and the torch member A are tilted, parts other than the sliding members 39 and 40 come into contact with the groove wall surface 37, resulting in poor running and sparking at a point other than the welding arc point. The effects of control are enormous.

If it is desired to maintain the inclination of the torch 24 at a constant angle to the perpendicular rather than parallel to the perpendicular, the mounting positions of the limit switches 25a and 25b may be changed.

Next, regarding the welding arc current, this current value is adjusted in advance according to the welding posture, groove shape, type of base materials 29, 29, etc. within the range of appropriate welding conditions. This becomes the reference current for the comparator circuit or operation box 28. The welding arc current is constantly compared with the reference current by the comparison circuit or operation box 28, and this comparison output operates the vertical movement mechanism to move the torch member A in the groove 30 up and down to adjust the discharge distance. This adjustment allows the torch 24 to move while always keeping the welding arc current consistent with the reference current. In this case, even if the bevel groove 30 is originally uneven, or there is a bead step due to the second or subsequent bathing, the above-mentioned torch elevating means acts while the vehicle is running. Therefore, the occurrence of undercuts and pores due to too large a current can be reduced, and the occurrence of poor penetration and slag entrainment due to too small a current can be prevented, and an optimum welding arc current can always be maintained.

Furthermore, since this current maintenance is performed simultaneously with the above-described torch posture control and the tracing of the groove wall surface 37 of the torch member, proper automatic tracing welding can be performed.

In the above embodiment, the torch lifting means is controlled by the welding arc current, but instead of this, the torch may be moved up and down so as to keep the distance between the torch and the base metal constant, or the arc length may be controlled. It goes without saying that other dynamic control means of the torch or the two-electrode torch may be modified within the scope of the present invention, such as by detecting the arc length and moving the torch up and down to keep the arc length constant.

The second pass is the torch 24 of the air cylinder 23.
By reversing the preload direction and pressing the torch member A against the other groove wall surface 36, groove tracing control can be performed in the same manner as described above.

〔Effect of the invention〕

In summary, the present invention exhibits the following excellent effects.

(1) The torch that guides the welding wire can be accurately moved along one of the groove walls in order to maintain proper welding conditions while controlling its posture, allowing for even and accurate automatic tracing welding. can be carried out. In particular, in the case of wide groove grooves that require one-layer, two-pass welding, one groove wall surface can be welded in the first pass, and the other groove wall surface can be traced in the second pass. It is possible to prevent poor penetration on the left and right sides that occurs when following the center of the groove.

(2) Since the torch member has two guide parts and a welding wire outlet is formed in the center,
Average profile welding connecting two points can be performed, and the influence of the uneven shape of the groove wall surface can be reduced, making it possible to perform stable welding.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an outline of a submerged arc welding device, Fig. 2 is a schematic front view showing an embodiment of a groove tracing device of a welding device according to the present invention, and Fig. 3 is a main part of Fig. 2. An enlarged cross-sectional view, FIG. 4 is an enlarged view of the main part, and FIG. 5 is an enlarged view of the main part of the pressing force means. In the figure, 12 is a carriage, 15 is a table,
24 is a torch, 29 is a base material, 30 is a bevel groove, 31
32 is a welding wire outlet, 32 is a running direction guide part,
33 is a backward direction guide part, 35 is a welding line, 36, 3
7 is a groove wall surface, A is a torch member, B is a torch pressing and urging means, 23 is an air cylinder as an example thereof, C is a torch attitude control means, which is a limit switch 25, a control circuit 27, and 16. It consists of a motor, and 1 is a perpendicular line.

Claims (1)

[Claims] 1. A carriage that runs in parallel along the groove groove formed between the base materials, and a table provided on the carriage so as to be able to reciprocate in the width direction of the groove;
A torch is provided on the table so as to be freely rotatable and swingable in the groove width direction, and is supported to run along the welding line in the groove groove, and a torch is inserted into the groove groove of the torch. A torch member having a welding wire outlet at the center of the lower end thereof, and a guide portion extending from the outlet in the longitudinal direction of the groove in the running direction and the backward direction. a torch pressing biasing means for prepressing the torch in the width direction of the groove, pressing the torch member against one of the groove wall surfaces, and pressing both the traveling direction guide section and the backward direction guide section against the groove wall surface; Torch posture control means that detects the inclination and moves the table according to the inclination to raise the torch at a predetermined angle with respect to a perpendicular to the welding line of the groove groove so as to face the welding wire outlet in a fixed position. A groove copying device for a welding device, characterized by comprising: