JP2001179448A - Automatic overhead welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide welding equipment which can freely travel on a road surface without using rails for traveling of the welding equipment, and to enable the overhead welding of members to be welded without being affected by obstacles such as the projecting and recessing parts, etc., of the road surface. SOLUTION: The welding equipment comprises a railless system traveling device 1 traveling on the road surface 100 by the autopilot system of wheels, a railless system welding machine 2 performing overhead welding while moving on the surfaces of the members to be welded 200, a boom device 3 installed on the traveling device and pivotally supporting the welding machine 2 at its tip part, a groove detection device 4 and having two groove profile sensors 41, 42 arranged before and behind in the proceeding direction of welding and oscillatable in the direction crossing a groove 210, an air cylinder 51 moving vertically the boom device 3, a turning device 6 turning the boom device 3, and a lateral moving device 7 moving the boom device 3 in the groove width direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an automatic upward welding apparatus for automatically performing upward welding of a large member such as a hull block.

[0002]

2. Description of the Related Art Conventionally, most of welding work in a construction dock handling a large structure is performed by a skilled welder. In particular, butt welding of a bottom shell is performed by hand welding from the inside of a hull. Had to be automated. However, when performing welding from inside the hull, there are many aggregates inside and it is necessary to carry out in a narrow space, so it is very difficult to install and operate welding equipment inside the hull . Therefore, it is more convenient to perform welding from the outside (lower side) of the hull, but in this case, the welding is upward welding.

[0003] In the case of upward welding, it is necessary to run a welding machine that supports devices such as a welding torch, a groove scanning sensor, and a backing material from below along a welding line. A rail is attached to an object to be welded in parallel with a welding line by using an attraction force of a magnet, and a welding head portion runs on the rail.
As disclosed in Japanese Patent Application Laid-Open No. 0-230359 and Japanese Patent Application Laid-Open No. 10-230360, there has been a method in which upward welding is performed while traveling while being attracted to the bottom plate of a ship using a traveling crawler of a magnet type.

[0004]

However, in the case of performing upward welding from the outside of the hull, unevenness on the surface of the culvert and the outer plate of the hull is particularly problematic. The road surface in the building dock has irregularities, and there are vertical and horizontal gradients and steps, and many cables and hoses used for welding and cutting are scattered. Therefore, even if the traveling rail of the welding machine is removably laid on the bottom of the culvert, it is necessary to eliminate or avoid these obstacles such as uneven portions and hoses.
The work is very complicated, and there are many difficulties in implementation. Also,
Even when the rail is directly attached to the object to be welded using magnets or the like, the surface of the bottom outer plate is not necessarily flat, and there are projections such as welding beads in addition to inclination and bending, and furthermore, the hull outer plate Similarly, rail mounting work is not easy due to the variety of forms. Therefore, the method using the rail is not suitable for upward butt welding of the bottom plate of the ship.

[0005] Further, in the case of using the attraction type traveling crawler as disclosed in the above-mentioned publication, when the magnetic force of the magnet is weak, it is necessary to limit the weight of the welding machine or to install a safety device in case of detachment. On the other hand, when the magnetic force is strong, there is a problem that the operation of desorption is difficult and inefficient. Therefore, the adsorption traveling type welding apparatus also has many practical difficulties.

Further, in order to realize automatic upward welding of the outer shell portion of a ship, in the construction dock, due to the characteristics of the dock,
It is impossible to move the welding joint, and the welding equipment cannot be permanently installed. Therefore, it is a natural prerequisite that it be mobile.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and can freely travel on a road surface without using a traveling rail of a welding device. It is an object of the present invention to provide an automatic upward welding device which enables upward welding of a member to be welded without being affected by obstacles.

[0008]

SUMMARY OF THE INVENTION An automatic upward welding apparatus according to the present invention is a trackless traveling means for traveling on a road surface by an automatic steering system of wheels, and performs upward welding by moving the surface of a member to be welded. A trackless type welding machine to be performed, a boom means installed on the traveling means and supporting the welding machine, and disposed in front of the welding machine, before and after in the welding traveling direction, and traversing the groove. Groove detecting means having two sensors capable of swinging in the direction of rotation, driving cylinder means for vertically moving the boom means, turning means for turning, and lateral moving means for moving the groove in the groove width direction. It is characterized by the following.

[0009] With this configuration, the traveling means travels on the road surface by the automatic steering system of the wheels without using the rail, and is attached to the tip of the traveling means via the boom means mounted on the traveling means. The welding machine also moves on the surface of the member to be welded without using a rail. Therefore,
The rail and the work of mounting and removing the rail are completely unnecessary. Further, during welding, the welding machine is pressed against the member to be welded by the drive cylinder means, so that there is no relative displacement between the welding torch and the surface of the member to be welded in the vertical direction. With respect to the groove width direction, two sensor means disposed before and after the welding machine in the front of the welding machine swing in the direction crossing the groove, so that the center of the groove and the center of the swing Can be detected. Since the angular displacement in the traveling direction of the welding machine with respect to the welding line direction is known from the two detected displacement amounts before and after, the displacement amount and the angular displacement are corrected by turning and laterally moving the boom means by the turning means and the lateral moving means. Thus, groove center scanning, that is, automatic welding line following can be performed.

[0010] In the automatic upward welding apparatus according to the present invention, the wheels of the traveling means are drive wheels having a steering function and at least two of the four wheels are arranged diagonally, and one of the wheels is provided on one side. It is characterized in that the front and rear two wheels are mounted on a chassis which is pivotally supported on the vehicle body in a cradle manner.

When traveling on a road surface having irregularities, gradients, steps or the like such as a bottom of a culvert, it is necessary for the traveling means to smoothly overcome these obstacles. One of the drive wheels having a steering function is attached to, for example, a front position of a cradle-type chassis, and the other drive wheel is disposed at a position behind a vehicle body that supports the cradle-type chassis. Even if there is, the cradle-type chassis swings up and down, so that the obstacle can be smoothly overcome with all wheels always in contact with the ground. Further, since the drive wheels have a steering function, the traveling means can be caused to travel such that the welding torch of the welding machine always moves on the welding line.

In the automatic upward welding apparatus according to the present invention, the traveling means includes a welding power source, a welding torch, a sensing device, a control device, a shielding gas supply device, a wire supply device, a cooling water supply device, and other welding equipment. It is characterized by being equipped with a set.

[0013] With this configuration, the automatic upward welding apparatus is made compact, and since cables and hoses are not routed, traveling on a narrow culvert can be smoothly performed.

Further, in the automatic upward welding apparatus according to the present invention, the welding machine has a sensor means for detecting a moving speed.

By this sensor means, the actual moving speed of the welding machine moving on the surface of the member to be welded is detected, and by correcting the running speed of the running means, a predetermined welding speed can be maintained.

Further, in the automatic upward welding apparatus according to the present invention, the welding machine has a sensor means for detecting an inclination angle of a welding line.

When the member to be welded has a curved surface, an inclined surface, or the like, the inclination angle of the welding line is detected by the sensor means, and the traveling speed of the traveling means is corrected in accordance with the inclination angle, so that a predetermined welding speed is obtained. Can be used to weld curved or inclined surfaces.

Further, in the automatic upward welding apparatus according to the present invention, the boom means is pivotally supported by the drive cylinder means, and the turning end provided to be able to move a base end of the boom on the lateral movement means. It is characterized in that it is supported by the turning shaft of the means.

With this configuration, the welding machine attached to the end of the boom can be turned by moving the turning axis of the turning means laterally, and the welding machine attached to the tip of the boom can be turned laterally. By laterally moving the moving shaft, the entire welding machine can be laterally moved in the groove width direction. Therefore, by controlling the amount of movement of the turning axis of the turning means and the amount of movement of the lateral moving axis of the lateral moving means on the basis of the displacement amount and the displacement angle detected by the two sensor means, automatic welding of the welding torch described above is performed. Line following can be performed. In addition, since the turning angle, that is, the steering angle can be detected from the lateral movement amount of the turning axis of the turning means, the traveling means can automatically steer based on this.

Further, in the automatic upward welding apparatus according to the present invention, the boom means has an extendable boom.

Especially when welding from a horizontal bottom shell to a bilge shell having a bend, the height of the weld from the bottom changes greatly, so that the boom means is configured to be extendable. Is preferred.

[0022]

FIG. 1 is a schematic side view of an automatic upward welding apparatus showing an embodiment of the present invention, FIG. 2 is a top view, and FIG.
Is a front view (however, the groove detection device at the front of the welding machine is omitted). This automatic upward welding apparatus is roughly divided into
A trackless traveling device 1 that travels on the vehicle 0 by an automatic steering system of wheels (the traveling direction is indicated by an arrow a); a boom device 3 that also supports a trackless welding machine 2 at a tip end;
In front of the welding machine 2, in the direction of welding progress (direction of arrow b)
A groove detecting device 4 for detecting a groove position by two sensors 41 and 42 before and after, a drive cylinder device 5 for turning the boom device 3 up and down, turning and moving left and right in a groove width direction, respectively, and a turning device 6. And the lateral moving device 7. The groove detecting device 4 having the two sensors 41 and 42, the turning device 6 and the lateral moving device 7 of the boom device 3 constitute an automatic welding line following mechanism of the welding machine 2. In the drawing, reference numeral 200 denotes a ship bottom outer plate portion of a member to be welded, 201 denotes an aggregate, and 210 denotes a groove.

As shown in FIGS. 4 and 5, the traveling device 1 further includes four wheels, at least two of which are drive wheels 11 having a steering function, and the other two are free wheels 12. . Further, the drive wheels 11 and the universal wheels 12 are respectively arranged on diagonal lines, and the two front and rear drive wheels 11 and the universal wheels 12 are supported on the vehicle body 10 by pins 13 so as to be swingable up and down in a cradle manner. Attached to chassis 14, all four wheels
Irrespective of the road surface condition of the culvert 100 (existence of irregularities, gradients, steps, and other obstacles such as hoses), it is always grounded so that these obstacles can be smoothly overcome (see FIG. 6). In the figure, reference numeral 15 denotes a driving motor for the driving wheel 11, 16 denotes a steering motor for the driving wheel 11, and a spur gear 17.
The wheel 11 is turned on a plane via the steering wheel to be steered. An encoder (not shown) for setting the steering angle of the drive wheel 11 is attached to the steering motor 16.

The boom device 3 is mounted on the vehicle body 10.
, A welding power source 81, a control device 82, a welding wire feeding device 83, a shielding gas supply device 84, a water cooling device 8, which are auxiliary equipments 8 necessary for welding.
5. Equipped with a set of welding equipment such as cables and hoses and an operation panel (not shown).

The welding machine 2 is composed of a trackless free running body which does not use rails.
The vehicle body 20 is pivotally supported on the tip of the boom 30 by two orthogonal pins 31 and 32, and the non-driven wheels 23
As a result, the outer surface (lower surface) of the bottom shell 200 is moved. In the figure, reference numeral 24 denotes an encoder for detecting the moving speed (welding speed) of the welding machine 2. The wheels 23 of the welding machine 2 are of a type that can be bidirectionally rotated in a traveling direction and a transverse direction perpendicular to the traveling direction, such as a product name “omni wheel”.

Although the welding method is not particularly limited, for example, a patent application (Japanese Patent Application No. 11-138) of the present applicant can be used.
No. 405) is suitable.
This method uses a small-diameter welding torch 2 as shown in FIG.
The curved tip portions 1 and 22 are inserted substantially horizontally into the groove gap, and are welded in one run (one run) by a lower leading electrode and a higher trailing electrode. In the figure, 24 is a welding wire for each electrode, 25 is a shield gas nozzle, 26
A backing material attached to the vehicle body 20 is made of, for example, a water-cooled copper plate, and slides on the lower surface of the groove 210 as the welding machine 2 moves. 27 is a preceding bead and 28 is a following bead.

The groove detecting device 4 is provided in front of the welding machine 2 and has two groove scanning sensors (for example, laser sensors) 41 and 42 disposed before and after in the welding traveling direction in a direction crossing the groove 210. It is configured to swing. The groove scanning sensors 41 and 42 are attached to the swing shaft 40 by a connecting plate 43. The oscillating shaft 40 is driven by a servomotor 44, and the oscillating position coordinates are detected by an encoder 45 attached to the servomotor 44. The swing mechanism of the groove scanning sensors 41 and 42 is formed of a known ball screw mechanism, and has a constant amplitude.
To reciprocate. The welding torches 21 and 22 are arranged such that the centers of the welding torches 21 and 22 are located on an extension of the swing center. The welding torches 21 and 22 are attached to a X-axis moving mechanism in a groove width direction, a Y-axis moving mechanism in a torch height direction, and a Z-axis moving mechanism in a welding line direction as position adjusting mechanisms (not shown). These moving mechanisms are also constituted by ball screw mechanisms. Further, a swing mechanism (not shown) is provided to swing the tip of the torch for weaving welding.

FIG. 8 is a diagram showing a groove width detecting method using a laser sensor of the groove copying sensor. This figure shows the relationship between the measurement length of the laser sensor obtained by the oscillation of the laser sensor and the coordinate position of the oscillation axis. Bevel 210
Because the opening is open, the measurement distance of the laser sensor is longer at the groove than at the bottom plate 200, so the coordinate position of the left end 211 of the groove changes suddenly (when the threshold value is exceeded). By detecting the coordinate position (+ x) of (−x) and the right end 212 of the groove, and obtaining the coordinate difference, the groove (opening) width G can be detected.

Therefore, as shown in FIG. 9, the difference between the center coordinate position of the groove and the center coordinate position of the rocking shaft is determined to obtain the displacement W with respect to the welding line (groove center line) 220. Can be requested. Further, since the displacement amount with respect to the welding line is determined for each of the two front and rear laser sensors 41 and 42, the displacement angle between the welding line 220 and the traveling direction of the welding machine can be determined. By making corrections using the turning device 6 and the lateral moving device 7, automatic beveling of the welding torches 21, 22 can be performed.

The boom device 3 is capable of performing various operations such as up and down (upturn), turning, and lateral movement of the boom 30 in the groove width direction. The vertical movement of the boom 30 is performed by a drive cylinder device, for example, an air cylinder 51.
The air cylinder 51 is also provided with the welding machine 2 at the end of the boom.
Is pressed against the hull outer panel 200. Therefore, the middle part of the boom 30 is connected to the cylinder rod 52 by means of T-shaped free shafts 33 and 34 with the middle part of the boom 30 as the center of rotation 33, and the base end of the boom is similarly T-shaped
5 and 36, it is connected to the turning shaft 60 of the turning device 6. The air cylinder 51 is connected to an outer frame of the turning device 6 by a pin 37.

Each of the turning device 6 and the horizontal moving device 7 installed thereunder is constituted by a known ball screw mechanism, and each of the turning shaft 60 and the horizontal moving shaft comprises a slide block which moves linearly in the groove width direction. 70.
Therefore, the boom 30 and the welding machine 2 can be turned around the vertical axis 33 of the free axes 33 and 34 by moving the turning axis 60 in the direction of the arrow c or d. The boom 30 and the entire welding machine 2 can be moved laterally in the groove width direction by laterally moving in the direction of the arrow e or f. The turning shaft 60 and the lateral moving shaft 70 of the boom 30 are driven by servo motors, respectively, and the amount of each movement is detected by an encoder attached to each servo motor.

Next, the operation of the automatic upward welding apparatus will be described. The automatic upward welding apparatus is installed on the culvert bottom 100, the boom 30 is lifted by the air cylinder 51, and the welding machine 2 attached to the boom tip is pressed against the bottom shell 200 from below. Next, the torch position adjusting mechanism positions the tips of the welding torches 21 and 22 at the target position of the welding wire 24 at the target position (here, the groove center position), and starts welding.

The butt welding of the outer shell portion 200 is an upward welding in which two electrodes of the welding torches 21 and 22 are used to finish in one run. The shield gas is blown from a nozzle (not shown) attached to each electrode and an upward nozzle 25 attached to the backing material 26. Further, while holding the molten pool by the water-cooled copper plate as the backing material 26, the water-cooled copper plate 26 is moved together with the welding machine 2 to perform welding (see FIG. 7).

The welding control is adaptive control based on groove information obtained from groove tracking sensors 41 and 42 provided in front of the welding machine 2 and optimum welding conditions extracted from a welding condition database. According to the experiment, when a steel plate having a thickness of 16 mm was carried out under the welding conditions shown in Table 1, good welding results were shown.

[0035]

[Table 1]

The upward butt welding of the bottom shell 200 is carried out by moving the welding machine 2 attached to the tip of the boom 30 along the welding line of the bottom shell 200 by the traveling device 1. You. Here, the traveling device 1 is a trackless type that does not use rails, and travels on the culvert 100 by an automatic steering method of the drive wheels 11.
The welding machine 2 is also of a trackless type, and has a boom 30
All the wheels 23 of the welding machine 2 come into contact with the bottom outer panel 200 by lifting the boom 30 with the air cylinder 51 because the boom 30 is lifted up and down and left and right by the pins 31 and 32 at the tip of the. It moves while being pressed at a constant pressure. For this reason, welding torch 21,
There is no relative displacement between the workpiece 22 and the member to be welded in the vertical direction.

As described above, the culvert bottom 100 has irregularities, gradients, steps, cables and hoses, and the like. However, the traveling device 1 has four wheels, at least two of which are driving wheels 11 having a steering function. The driving wheels 11 and the universal wheels 12 are arranged diagonally, and the two front and rear wheels on one side are driven. Since the wheel 1 and the universal wheel 12 are mounted on a cradle-type chassis 14 pivotally supported by pins 13, the traveling device 1, as shown in FIG. The obstacle 110 such as unevenness can be smoothly overcome. Also,
Lifting force or sinking force acting on the vehicle body 10 when the driving wheel 11 or the universal wheel 12 passes over the obstacle 110,
Alternatively, since the air cylinder 51 absorbs some impact force or the like, the pressing state of the welding machine 2, in other words,
It does not affect the welding state by the welding torches 21 and 22 at all. Note that a trapezoidal tread plate may be placed on cables and hoses that cross the traveling path.

Further, on the vehicle body 10 of the traveling device 1, a welding power source 81, a control device 82, a welding wire feeding device 83, a shielding gas supply device 84, a water cooling device 85, other cables and hoses and an operation panel (FIG. (Not shown) etc., so that cables and hoses can be shortened, and the cables and hoses are not routed, so that traveling in a narrow culvert can be performed smoothly.

Next, an automatic groove copying method during welding will be described. Two groove profiling sensors 41 and 42 before and after in the welding progress direction are provided in front of the welding machine 2 with a groove 21.
Since the oscillating shaft 40 oscillates at a constant amplitude in the direction crossing 0, the coordinate position of the left end of the groove and the coordinate position of the right end of the groove are determined by the change of the measurement distance of the groove copying sensors 41 and 42. It can be detected in relation to the moving coordinates (see FIGS. 8 and 9).
The opening width G of the groove 210 is obtained from the coordinate difference between the left end position and the right end position of the groove 210 thus detected.
20 to obtain the groove profiling sensor 4 respectively.
The displacement amounts Wf and Wr of the first and second swing centers are obtained.

From these two displacement amounts, it is possible to know how much the angle of the traveling direction of the welding machine 2 deviates from the welding line (the groove center line). FIG. 10 is a schematic view of the arrangement of the welding line and the groove profiling sensors (laser sensors) 41 and 42 when the direction of the groove line is shifted to the left with respect to the traveling direction of the welding machine 2 as viewed from the bottom. FIG. 11 shows the relationship between the swing axis coordinate position detected by the two groove copying sensors 41 and 42 and the length measurement distance at this time. From the displacement amounts Wf and Wr from the respective swing centers to the groove centers detected by the two groove profiling sensors 41 and 42, the displacement angle θ with respect to the welding line in the welding machine advancing direction is obtained from the equation (1). You can ask.

[0041]

(Equation 1)

The welding torches 21 and 22 are on the extension of the swing center of the groove copying sensors 41 and 42 attached to the front part of the welding machine 2, and the welding machine 2 is attached to the tip of the boom 30. The base end of the boom 30 has a free shaft 35,
36, and the middle part of the boom 30 is supported by the air cylinder 51 via the free shafts 33 and 34. The welding machine 2 can be turned around the shaft 33 on the upper part of the air cylinder. Further, by moving the lateral movement axis 70 of the lateral movement device 7 to which the turning device 6 is attached in the left-right direction, the welding machine 2 as a whole is
It can be moved laterally left and right by 0.

Therefore, the welding machine 2 is turned or moved laterally based on the information of the displacement amount and the displacement angle with respect to the welding line 220 detected by the groove profiling sensors 41 and 42, and the groove profiling sensors 41 and 42 are used. , The welding torches 21 and 22 can always be positioned on the groove center line (welding line).

This correction method will be described with reference to FIGS. FIG. 12 is a diagram of an automatic welding line copying mechanism, and FIG. 13 is a conceptual diagram of a control method thereof. The displacement angle is corrected by turning the boom 30. At this time, the correction movement amount (D1) of the turning shaft 60 is determined by the two groove scanning sensors 41, 4
The difference between the displacement amount (Wr-Wf) of 2 and the lever ratio of the length between the sensors (L) and the length (L2) from the boom turning center 33 to the boom turning movement point 36 can be obtained from Expression (2). .

[0045]

(Equation 2)

The displacement is corrected by moving the boom 30 laterally. At this time, the corrected movement amount (D2) of the horizontal movement shaft 70 is calculated by the following equation (3).
And the displacement (d) newly generated due to the correction of the displacement angle of the boom 30 are calculated. D2 = Wr + d (3)

Displacement generated by displacement angle correction (d)
Is, as shown in equation (4), two groove scanning sensors 4
1, the displacement amount difference (Wr-Wf), the inter-sensor length (L) and the boom turning center 33 to the rear groove scanning sensor 4
It can be obtained from the lever ratio of the length (L1) up to 2.

[0048]

(Equation 3)

The corrected movement amounts (D1, D2) of the revolving shaft 60 and the lateral movement shaft 70 obtained in this way are commanded to the respective drive servomotors 61, 71 to simultaneously operate both shafts. Performs copying control.

Next, a method for automatically following a welding line will be described. Unlike the conventional welding device, the traveling device 1 according to the present invention employs a traveling method that does not use a rail, and thus needs to perform automatic steering traveling along a welding line. In order to perform automatic steering travel, first, the welding line direction and the traveling device 1
It is an essential condition to detect the displacement angle with respect to the traveling direction. Here, the displacement angle between the welding line direction and the traveling direction of the traveling device 1 is detected from the turning angle of the boom 30 to which the welding machine 2 is attached.

FIG. 14 shows a method for detecting the displacement angle between the direction of the welding line and the traveling direction of the traveling device 1. The front of the welding machine 2 attached to the tip of the boom 30 has two fronts and backs on the welding line.
Two groove profiling sensors 41 and 42 are attached,
A groove tracing control mechanism that performs groove tracing by turning or boom-moving the boom 30 so that the center of swinging of the two groove tracing center differences 41 and 42 is always on the welding line 220 is operating. In other words, the boom 30 is always oriented in the same direction as the welding line 220 by the groove following control mechanism. This means that if the turning angle of the boom 30 is detected, the welding line direction and the traveling device 1
Means that the displacement angle with respect to the traveling direction of the vehicle is detected.

The turning angle α of the boom 30 is, as shown in FIG. 14, the length (the connecting pin between the boom turning center 33 and the air cylinder 51) and the turning force point 36 (the connecting pin with the boom turning shaft 60). L2) and the distance (the lateral movement position of the boom turning shaft 60) from the turning center line (the running direction of the traveling device 1) 221 of the boom turning shaft 60 can be obtained by Expression (5).

[0053]

(Equation 4)

FIG. 15 shows a method of steering the traveling device 1. There are two steering / drive wheels 11 on the front left wheel and the rear right wheel of the vehicle body 10. The drive motor 15 is directly connected to the wheels 11, and is rotated by a steering motor 16 via a spur gear 17 to rotate the wheels 11 on a plane to perform steering. Steering the two front and rear wheels 11 enables not only front wheel steering traveling but also traversing traveling and turning, so that movement on a narrow culvert can be performed smoothly.

FIG. 16 is a conceptual diagram of the steering control method. Lateral movement position information of the boom 30 detected from an encoder attached to the servo motor of the boom turning shaft 60;
The turning angle of the boom 30 is detected from the length (predetermined value) between the turning center 33 of the boom turning shaft 60 and the action point 36. The boom turning angle is a displacement angle between the welding line direction and the traveling direction of the traveling device 1, and is also a steering angle of the traveling device 1. Therefore, the detected boom turning angle is used as a steering command angle as a steering command angle to the front drive wheel 11 of the traveling device 1 for steering. Thus, the trackless traveling device 1 can always automatically follow the welding line.

Next, a method of controlling the traveling speed of the traveling device will be described with reference to FIGS. 17 is a schematic side view showing the relationship between the traveling direction of the traveling device and the welding direction on an uneven road surface, and FIG. 18 is a schematic top view showing the relationship between the traveling direction of the traveling device and the welding direction when the traveling device is steered. Figure, Figure 1
9 is a conceptual diagram of a traveling speed control method of the traveling device.

Since the traveling device 1 travels on the culvert 100 having obstacles 110 such as irregularities, the traveling direction of the traveling device 1 is not the same as the welding direction, but produces an angle difference.
However, simply instructing the welding speed to the target cannot obtain the desired welding speed. As a countermeasure, an encoder 24 is attached to the wheels 23 of the welding machine 2, the encoder 24 detects the actual moving speed (welding speed) of the welding machine 2, and detects the actual welding speed (command speed from the welding condition database) and the actual speed. Is determined with respect to the welding speed (detected speed of the encoder 24), and the traveling speed of the traveling device 1 is corrected based on the difference.

That is, as shown in FIG. 19, in this traveling speed control method, the difference between the command welding speed from the welding condition database and the actual welding speed (detected speed of the encoder 24) and this difference are stored in the welding condition database. In this method, the value added to the command welding speed is commanded to the drive wheels 11 of the traveling device 1 to control the traveling speed of the traveling device 1. Therefore, the traveling speed command value of traveling device 1 = welding speed command value +
(Welding speed command value-movement speed of welding machine 2).

Further, this automatic upward welding apparatus enables continuous welding not only to the hull bottom plate 200 but also to the bilge plate 202. FIG. 20 is a schematic side view showing the relationship between the traveling speed of the traveling device and the welding speed during bilge outer plate welding, and FIG. 21 is a conceptual diagram of a traveling speed control method of the traveling device.

In the welding of the horizontal bottom plate 200, the traveling speed of the traveling device 1 becomes the welding speed as it is because the welding line is parallel to the bottom 100. However, in the bilge outer plate 202 having a bend, an angle is generated between the traveling direction of the traveling device 1 and the welding line direction, and the angle increases as welding progresses, so that the traveling speed and the welding speed greatly differ. Therefore, the traveling speed of the traveling device 1 is controlled so that the target welding speed can be obtained also in the bilge outer plate portion 202.

For this purpose, an inclination sensor 25 for detecting the inclination of the welding line is attached to the welding machine 2 so that the boom 30 can be extended and contracted. Here, the telescopic boom 30a extends and contracts inside the support boom 30b.

As shown in FIG. 21, the traveling speed control method is based on the welding speed command value from the welding condition database based on the detection angle of the inclination angle sensor 25 attached to the welding machine 2 as shown in equation (6). The traveling speed of the traveling device 1 is calculated by vector conversion, and the result is converted to the driving wheel 1 of the traveling device 1.
The welding speed is controlled by instructing to 1. Vc = cos θ · Vw (6) where Vc: traveling speed of the traveling device (cm / min) θ: inclination angle of the welding machine (゜) Vw: welding speed command value (c from the welding condition database)
m / min)

By controlling the traveling speed of the traveling device 1 in this manner, the bilge outer plate 20
Continuous welding at the target welding speed up to 2 is possible. The telescopic boom 30a can be erected up to 90 degrees by the air cylinder 51, and by extending the telescopic boom 30a, welding to a height of about 4 m from the culvert bottom 100 is possible.

[0064]

As described above, according to the present invention,
As it is possible to automatically weld large workpieces such as the bottom shell part from outside without using rails,
Welding efficiency is improved. In addition, the traveling means can travel on a road surface having unevenness or a gradient such as a culvert, and the welding machine is moved along the surface of the material to be welded through a boom means capable of moving up and down, turning and laterally moving. The welding line can be automatically followed by two front and rear sensors provided at the front of the welding machine so as to be swingable in a direction crossing the groove.

[Brief description of the drawings]

FIG. 1 is a schematic side view of an automatic upward welding apparatus according to the present invention.

FIG. 2 is a schematic top view of the same device.

FIG. 3 is a schematic front view of the same device.

FIG. 4 is a schematic top view of the traveling device.

FIG. 5 is a schematic side sectional view of the traveling device.

FIG. 6 is an explanatory diagram of an operation of the traveling device on an uneven road surface.

FIG. 7 is an explanatory view showing a welding method.

FIG. 8 is an explanatory diagram showing a groove width detection method using a laser sensor.

FIG. 9 is an explanatory diagram showing a method of measuring the amount of displacement between the oscillation center and the groove center of the laser sensor.

FIG. 10 is a view of the groove detection device as viewed from the bottom of the pit when the welding line is shifted leftward with respect to the traveling direction of the welding machine.

FIG. 11 is an explanatory diagram showing displacement amounts of a front laser sensor and a rear laser sensor when a welding line is shifted leftward with respect to a traveling direction of a welding machine.

FIG. 12 is an explanatory view showing an automatic welding line copying mechanism.

FIG. 13 is a conceptual diagram showing an automatic welding line scanning control method.

FIG. 14 is an explanatory diagram illustrating a method of detecting a displacement angle between a welding line direction and a traveling direction of a traveling device.

FIG. 15 is an explanatory diagram illustrating a steering method of the traveling device.

FIG. 16 is a conceptual diagram showing a steering control method of the traveling device.

FIG. 17 is a schematic side view showing a relationship between a traveling direction of the traveling device and a welding direction on an uneven road surface.

FIG. 18 is a schematic top view showing a relationship between a traveling direction of the traveling device and a welding direction when the traveling device performs steering traveling.

FIG. 19 is a conceptual diagram showing a traveling speed control method of the traveling device.

FIG. 20 is a schematic side view showing the relationship between the traveling speed of the traveling device and the welding speed during bilge outer plate welding.

FIG. 21 is a conceptual diagram showing a traveling speed control method of the traveling device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling device 2 Welding machine 3 Boom device 4 Groove detecting device 5 Fluid pressure cylinder device 6 Revolving device 7 Lateral moving device 8 Attached device 10 Body 11 Drive wheel 12 Free wheel 14 Undercarriage 21, 22 Welding torch 23 Wheel 24 Encoder 30 Boom Reference Signs List 30a telescopic boom 30b support boom 40 swing shaft 41, 42 groove tracking sensor 51 air cylinder 60 turning axis 70 lateral movement axis 100 culvert bottom 200 ship bottom outer plate part 210 groove

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Murayama 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd. (72) Inventor Takanobu Sano 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Sun (72) Inventor Yuji Sugitani Inside 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan Co., Ltd.

Claims (7)

[Claims] A trackless traveling means for traveling on a road surface by an automatic steering system of wheels, a trackless welding machine for performing welding by moving a surface of a member to be welded, and a welding machine installed on the traveling means, Boom means for pivotally supporting the welding machine; groove detection means having two sensors disposed in front of the welding machine in front and rear of the welding direction and capable of swinging in a direction crossing the groove. An automatic upward welding apparatus comprising: a driving cylinder means for vertically moving the boom means; a turning means for turning; and a lateral moving means for moving the boom means in a groove width direction. 2. The vehicle of claim 1, wherein at least two of the four wheels are driving wheels having a steering function and at least two of the four wheels are arranged diagonally. The automatic upward welding apparatus according to claim 1, wherein the automatic upward welding apparatus is attached to a supported chassis. 3. The traveling means is equipped with a set of welding equipment such as a welding power source, a welding torch, a sensing device, a control device, a shield gas supply device, a wire feed device, and a cooling water supply device. The automatic upward welding apparatus according to claim 1. 4. The automatic upward welding apparatus according to claim 1, wherein said welding machine has a sensor means for detecting a moving speed. 5. The automatic upward welding apparatus according to claim 1, wherein said welding machine has a sensor means for detecting an inclination angle of a welding line. 6. The boom means is pivotally supported by the drive cylinder means, and a base end of the boom is pivotally supported by a turning shaft of the turning means movably provided on the lateral moving means. The automatic upward welding apparatus according to claim 1, wherein: 7. The automatic upward welding apparatus according to claim 1, wherein said boom means has a boom which can be extended and contracted.