WO2024070354A1

WO2024070354A1 - Vertical-position welding device and control method for vertical-position welding device

Info

Publication number: WO2024070354A1
Application number: PCT/JP2023/030389
Authority: WO
Inventors: 元章村上; 亮戸田
Original assignee: 株式会社神戸製鋼所
Priority date: 2022-09-30
Filing date: 2023-08-23
Publication date: 2024-04-04
Also published as: JP2024051883A

Abstract

Provided is a vertical-position welding device for performing welding in a vertical-position orientation with respect to a groove formed by two welding target members, said vertical-position welding device comprising a welding carriage that travels along the groove on one surface side perpendicular to the plate thickness direction of the welding target members while welding is performed, and a welding torch that is mounted on the welding carriage. The welding carriage has two or more guide rollers that are disposed side-by-side along the welding advancement direction and that advance along the direction in which the groove extends, and a detection means that detects the amount of shifting of the welding carriage in the welding advancement direction with respect to the direction in which the groove extends. At least one of the guide rollers is a movable guide roller which can be moved parallel to a direction orthogonal to the welding advancement direction with use of a driving means. The driving means performs driving control for pressing the movable guide roller against a groove surface so as to cause movement in a direction that cancels the amount of shifting detected by the detection means.

Description

Vertical welding apparatus and method for controlling vertical welding apparatus

The present invention relates to a self-propelled vertical welding device and a method for controlling the vertical welding device.

Vertical welding is performed in a variety of manufacturing industries, including shipbuilding, steel building structures, and energy plants. There is a demand for automation of this vertical welding, and conventionally known welding equipment that achieves this includes rail-type vertical welding equipment and non-rail-type vertical welding equipment (hereinafter also referred to as self-propelled vertical welding equipment).

Among these welding devices, rail-type vertical welding devices have high welding precision but require rails to be installed in advance on the workpiece side, which reduces work efficiency. On the other hand, self-propelled vertical welding devices do not require rails or other equipment to be installed in advance on the workpiece side, so they are more efficient than rail-type vertical welding devices. Self-propelled vertical welding devices include a hanging type that pulls up the welding device, and a magnet wheel type that uses magnetic force to attach it to the workpiece.

An example of this self-propelled vertical welding device is the patent document 1. The patent document 1 discloses that the traveling rollers of the welding carriage are rotated by an electric motor, and that by providing fine grooves on the entire circumference of the roller surface, the welding carriage can be securely held on the side to be welded, and there is no risk of the welding carriage falling, etc., and welding can be performed while correcting misalignment of the groove.

Japan Patent Publication No. 53-155522

However, the self-propelled vertical welding device described in Patent Document 1 may cause the welding position to shift due to changes in the attitude of the welding carriage caused by working conditions or disturbances. Factors related to the working conditions include, for example, when welding a groove formed at the butt joint of two workpieces, the plate thicknesses of the two workpieces may be different, or the plate thickness at the plate joint may be different. Factors related to disturbances include, for example, misalignment in the plate thickness direction.

Self-propelled vertical welding equipment generally has a pair of left and right running rollers arranged to straddle the butt joint, and welding work is performed while self-propelled along the extension direction of the groove, which is the welding progress direction. However, due to the above factors, a difference in the travel distance between the left running rollers and the right running rollers arranged to straddle the opposing welded materials may occur. As a result, in conventional self-propelled vertical welding equipment, the attitude of the welding carriage rotates left and right in the welding progress direction with the guide roller pressed into the groove as a fulcrum, so that the left and right positions of the welding torch installed behind the welding carriage in the traveling direction are also misaligned, and as a result, the welding position may deviate from the groove position, leading to a decrease in welding quality. For this reason, there is a demand for a self-propelled vertical welding equipment that can stabilize the attitude of the welding carriage even under various construction conditions and disturbances.

The present invention was made in consideration of the above situation, and its purpose is to provide a self-propelled vertical welding device that can stably maintain the working position of the welding carriage, and a control method for the self-propelled vertical welding device.

The above object of the present invention is achieved by the following configuration [1] relating to a vertical welding apparatus.
[1] A vertical welding device for performing welding in a vertical position on a groove formed by two workpieces,
A welding carriage that welds one surface side perpendicular to the plate thickness direction of the welded material while traveling along the groove, and a welding torch mounted on the welding carriage,
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove;
A detection means for detecting a deviation amount of the welding proceeding direction of the welding carriage relative to the extension direction of the groove,
At least one of the guide rollers is a movable guide roller that can be moved in parallel in a direction perpendicular to the welding proceeding direction by a driving means,
The vertical welding device is characterized in that the driving means performs drive control to press the movable guide roller against the groove surface so that the movable guide roller moves in a direction that cancels the amount of deviation detected by the detection means.

The above object of the present invention is achieved by the following configuration [2] relating to a control method for a vertical welding apparatus.
[2] A control method for a vertical welding apparatus for performing welding in a vertical position on a groove formed by two workpieces, comprising:
The vertical welding apparatus includes a welding carriage that welds one surface side perpendicular to the plate thickness direction of the workpiece while traveling along the groove, and a welding torch mounted on the welding carriage;
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove,
At least one of the guide rollers is a movable guide roller that is movable in parallel in a direction perpendicular to the welding proceeding direction,
a movable guide roller that presses the groove surface in a direction in which the amount of deviation is detected when a deviation of the welding carriage in the welding proceeding direction with respect to an extension direction of the groove is detected.

According to the present invention, in a self-propelled vertical welding device that does not require rail installation and a control method for the vertical welding device, the posture of the welding carriage is stably maintained and deviation of the welding torch tip position is suppressed, thereby ensuring good welding quality.

FIG. 2 is a perspective view showing a vertical welding apparatus. FIG. FIG. This is a cross-sectional view taken along line AA in FIG. This is a cross-sectional view taken along line B-B of FIG. This is a cross-sectional view taken along the line CC of FIG. FIG. 4 is a diagram showing the configuration of a drive unit air circuit. Figure 8 (A) is a model diagram showing a reference position and a current position photographed by a visual sensor, Figure 8 (B) is a model diagram showing a state in which the visual sensor detects that the amount of deviation is less than a threshold value, and Figure 8 (C) is a model diagram showing a state in which the visual sensor detects that the amount of deviation is greater than or equal to the threshold value. 9A to 9D are schematic diagrams showing the effect of drive control. FIG. 4 is a flow chart showing a drive control process.

Below, an embodiment of the self-propelled vertical welding device and the control method for the vertical welding device according to the present invention will be described with reference to the attached drawings. Note that each figure has been created for the purpose of explaining the present invention, and the embodiment of the present invention is not limited to the contents shown in the drawings. In addition, the welding method to which the vertical welding device is applied is not particularly limited, but examples of welding methods include electroslag welding and electrogas welding. In this embodiment, the case of use in electroslag welding will be described as an example.

In this embodiment, the weld line direction is the X-axis. This X-axis weld line direction is synonymous with the direction along the groove centerline, and is also synonymous with the extension direction of the groove, which will be described later. Furthermore, the direction perpendicular to the weld line on the X-Y plane, which is the surface on which the materials to be welded are welded, is the Y-axis. The direction of this Y-axis is synonymous with the groove width direction. Furthermore, the plate thickness direction of the materials to be welded, which is the direction perpendicular to the plane of the materials to be welded on which welding is performed, is the Z-axis.

Furthermore, with regard to the surface of the workpiece on which welding is performed, the surface on which the welding carriage described below runs is referred to as the "front surface," and the opposite surface is referred to as the "back surface." The front surface is the surface in the +Z direction, and the back surface is the surface in the -Z direction. With respect to the direction of the Z axis, the +Z direction, which is the front surface direction, is referred to as "upward," and the -Z direction, which is the back surface direction, is referred to as "downward."

Furthermore, the direction in which welding proceeds with respect to the vertical welding device as the reference is referred to as "forward," and the direction in which it retreats is referred to as "rearward." Forward is the +X direction, and rearward is referred to as the -X direction. The welding device of this embodiment performs upward welding in a vertical position on the workpiece, so welding toward the front is synonymous with welding upward.

The directions of rotation relative to the direction of travel along the -X axis are called "right" and "left." Right is the +Y direction, and left is the -Y direction.

<Vertical welding equipment>
Figures 1 to 6 show an example of the configuration of a vertical welding apparatus according to an embodiment. Figures 1 to 3 are a perspective view, a front view, and a side view of the vertical welding apparatus. Figure 4 is a cross-sectional view taken along line A-A in Figure 2. Figure 5 is a cross-sectional view taken along line B-B in Figure 2. Figure 6 is a cross-sectional view taken along line C-C in Figure 3.

The vertical welding device 1 comprises a welding carriage 2 that travels forward in a vertical position over a pair of

steel plates

5, 5 that are the workpieces to be welded, an electric winch 3 that hoists the welding carriage 2 so that it travels upward over the surface of the steel plates 5, and a welding torch 4 mounted on the welding carriage 2. The pair of

steel plates

5, 5 are positioned spaced apart from each other in the left-right direction so that a groove 10 that extends in the up-down direction is formed between them. Note that, with respect to the direction in which welding progresses, the left workpiece of the pair of

steel plates

5, 5 is referred to as steel plate 5A, and the right workpiece is referred to as steel plate 5B. When describing the

steel plates

5A and 5B as a set, they are referred to as steel plate 5.

As shown in FIG. 1 etc., the welding carriage 2 includes a main frame 6, running rollers 7 that slide on the surface of the steel plate 5, guide rollers 8 that are placed in the groove 10 during welding work, a front copper plate support part 11 that supports the front copper plate 9 so that it can be pressed against the front side of the groove 10, a back copper plate support part 13 that supports the back copper plate 12 so that it can be pressed against the back side of the groove 10, a visual sensor 14 as a detection means for detecting the welding work position, and a control part (not shown). The welding carriage 2 is configured to be able to perform electroslag welding by traveling forward along the X-axis direction, which is the weld line direction, while welding between the grooves 10 in the vertical direction. Each component will be described in detail below.

<Electric winch>
The electric winch 3 is installed above the steel plate 5 on which welding work is performed and in front of the welding carriage 2, and suspends and supports the welding carriage 2. The electric winch 3 is configured to be able to move the welding carriage 2 forward along the X-axis direction, which is the vertical weld line direction, by lifting the welding carriage 2. The traveling speed of the welding carriage 2 depends on the hoisting speed of the electric winch 3, and the traveling speed during welding work, i.e., the welding speed, can be adjusted by adjusting the hoisting speed of the electric winch 3. The hoisting speed of the electric winch 3 is configured to be controllable by the control unit. By configuring the welding carriage 2 to be hoisted by the electric winch 3, it is not necessary to wire motor power lines and signal lines to a distant location, as compared with a case in which a general winch and a suspended load (welding carriage) are separated, so that the entire vertical welding device can be configured compactly.

In addition, as a self-propelled vertical welding device in which the welding carriage 2 travels upward in a vertical position above the steel plate 5, the traveling rollers 7 of the welding carriage 2 may be powerful magnets that are attached to the steel plate 5, and the traveling rollers 7 attached to the steel plate 5 may be driven by a drive unit (not shown) provided on the welding carriage 2 side, allowing the welding carriage 2 to travel upward in a vertical position.

<Welding torch>
The welding torch 4 is supported on the welding carriage 2 side via a torch support part 16, which will be described later in detail. This allows the welding torch 4 to adjust the welding position in the Y-axis direction, which is the groove width direction and which is the left-right rotation direction of the welding carriage 2, and in the Z-axis direction, which is the plate thickness direction of the steel plate 5. The torch support part 16 also has a posture adjustment mechanism 17 that adjusts the vertical swing position of the welding torch 4, and is configured to allow the welding torch 4 to be directed toward the slag bath at an angle suitable for welding work. The specific configuration of the torch support part 16 will be described later.

The welding torch 4 has a contact tip that guides the welding wire so that it is fed toward the groove 10, and is configured to be able to weld the groove 10 formed between a pair of

steel plates

5A, 5B by supplying the welding wire with a welding current supplied from a welding power source (not shown).

Specifically, the welding torch 4 feeds the welding wire guided by the contact tip into the groove 10 surrounded by a pair of

steel plates

5A, 5B, a front copper plate 9, and a back copper plate 12, thereby feeding the welding wire into the slag bath, which is a molten pool formed in the groove 10, and at the same time, the welding current can be passed from the welding wire through the slag bath to the molten metal. This generates Joule heat due to the welding current passed through the slag bath and the electrical resistance of the slag bath, making it possible to perform electroslag welding, in which welding proceeds while melting the welding wire and steel plates.

<Main body frame>
1 and 2, the main body frame 6 has main body frames 18 which are a pair of left and right plate-like members extending along the traveling direction of the welding cart 2, and a pair of front and rear connecting

rods

19, 20 which extend in the left and right direction so as to connect the opposing surfaces of the pair of left and right main body frames 18, 18, and is formed in a frame shape which is open in the X-axis direction which is the front-rear direction and in the Z-axis direction which is the up-down direction. A U-shaped winch support frame 21 which protrudes forward in a plan view is formed so as to span the front end side of the main body frame 6, and an electric winch 3 which hoists the welding cart 2 is attached and fixed via the winch support frame 21.

<Running roller>
The running rollers 7 have a pair of left and right

front wheels

7A, 7A and a pair of left and right

rear wheels

7B, 7B provided on the main body frame portion 6 side, and are configured so that the main body frame portion 6 can slide stably on the surface of the steel plate 5.

As shown in Figure 4 etc., the front wheel support shaft 22, a rod-shaped member extending in the left-right direction, is supported at the center of the front connecting rod 19 so that it can swing up and down. A pair of left and right

front wheels

7A, 7A are supported at both left and right ends of the front wheel support shaft 22. Similarly, the rear wheel support shaft 23, a rod-shaped member extending in the left-right direction, is supported at the center of the rear connecting rod 20 so that it can swing up and down. A pair of left and right

rear wheels

7B, 7B are supported at both left and right ends of the rear wheel support shaft 23.

With this configuration, even if the surface of the self-propelled steel plate 5 has slight irregularities or inclinations, the swinging action of the front wheel support shaft 22 and the rear wheel support shaft 23 can absorb positional deviations of the main body frame 6 and the welding torch 4, making welding work by the self-propelled welding cart 2 more stable.

<Front copper plate support>
The front copper plate support part 11 supports the front copper plate 9 arranged on the rear side of the welding carriage 2 on the surface of the steel plate 5. The front copper plate support part 11 has front copper

plate air cylinders

24, 24 as a pair of left and right actuators that press the front copper plate 9 against the surface of the steel plate 5, a front side link mechanism 25 that operates the front copper plate 9 by the pair of front copper

plate air cylinders

24, 24, and a torch support part 16 that supports the welding torch 4.

The front copper plate 9 is a plate-shaped member with a pressure surface that contacts the surface of the steel plate 5, and is generally equipped with a water-cooled cooling mechanism (not shown). The front copper plate 9 forms part of the slag bath by contacting the surface of the steel plate 5, and in this state the welding carriage 2 moves independently while performing welding work, allowing it to slide over the groove 10 while cooling the slag bath.

As shown in Figures 1 to 3, the front copper plate air cylinder 24 is provided in a pair on the left and right sides of the main body frame 6, with the front end of the head side attached and fixed to the front outer surface of the main body frame 18 via a fixing plate 26, which is a plate-shaped member in the front-rear direction, and the rear end of the operating rod side connected to the front link mechanism 25. As a result, the front copper plate air cylinder 24 is attached and fixed to the main body frame 18 side of the main body frame 6 with the operating direction of the operating rod facing diagonally upward and rearward.

As shown in FIG. 3, the front link mechanism 25 has a front drive link member 28 which is a driving link extending in the front-rear direction, a front driven link member 31 which is a driven link extending in the front-rear direction, and a front intermediate link member 32 which is an intermediate link extending in the up-down direction.

The front drive link members 28 are a pair of left and right link members that correspond to the front copper plate air cylinders 24, and their front ends are connected to the rear lower side of the main frame 18 via the first connecting joint 27, and their rear ends are connected to the front intermediate link member 32 via the third connecting joint 33.

The front side driven link members 31 are a pair of link members provided on the left and right outer sides of the main body frame 6, with their front ends connected to the upper rear side of the main body frame 18 via the second connecting joint 29 and their rear ends connected to the front side intermediate link member 32 via the fourth connecting joint 34.

The front intermediate link member 32 extends in the vertical direction, which is the thickness direction of the steel plate 5, and its lower end is connected to the rear end of the front driving link member 28 via a third connecting joint 33, and its vertical midpoint is connected to the rear end of the front driven link member 31 via a fourth connecting joint 34.

As shown in FIG. 1, the third connecting member 33 connects the rear ends of the pair of left and right front

drive link members

28, 28 with a rod-shaped member extending in the left-right direction, and the fourth connecting member 34 connects the rear ends of the pair of left and right front driven

link members

31, 31 with a rod-shaped member extending in the left-right direction.

At this time, the front side driving link member 28 and the front side driven link member 31 are formed to be approximately the same length. In addition, the line connecting the first connecting section 27 and the second connecting section 29 is arranged so as to be perpendicular to the traveling direction of the welding cart 2. In addition, the distance between the third connecting section 33 and the fourth connecting section 34 on the front side intermediate link member 32 is formed to be approximately the same length as the distance between the first connecting section 27 and the second connecting section 29. In other words, the front side link mechanism 25 constitutes a four-section link with a closed loop structure formed in the shape of a parallelogram in a side view.

As shown in FIG. 3 etc., the front drive link member 28 is integrally formed with a front operation arm portion 28a that extends forward and upward from the first connecting joint 27, and the operating rod of the air cylinder 24 for the front copper plate is connected to the front end of the front operation arm portion 28a. The connecting joint between the front operation arm portion 28a and the operating rod is located forward and upward of the second connecting joint 29 in a side view.

Also, as shown in FIG. 3 etc., the front intermediate link member 32 has a front copper plate 9 on its protruding lower end below the third connecting section 33, i.e., on the steel plate 5 side, and is supported so that the pressure surface of the front copper plate 9 can abut against the surface of the steel plate 5.

With the front link mechanism 25 of this configuration, the operating force associated with the extension and contraction of the operating rod of the air cylinder 24 for the front copper plate acts in the order of the operating rod → front operation arm part 28a → front drive link member 28 → front intermediate link member 32 and front copper plate 9 → front driven link member 31, so that the front intermediate link member 32 and front copper plate 9 perpendicular to the steel plate 5 can be moved up and down while maintaining their posture. In other words, with the front copper plate support part 11 described above, it is possible to operate the pressure operation for pressing the front copper plate 9 against the front side of the steel plate 5 and the release of the pressure operation of the front copper plate 9. Note that the actuator for operating the front link mechanism 25 may be an electric cylinder or a motor instead of the air cylinder 24 for the front copper plate.

The torch support 16 has a left-right connecting support part 35 that connects the upper ends of the pair of left and right front intermediate link members 32, a welding position adjustment mechanism 36 that is attached and fixed to the front side of the connecting support part 35 and has an operating part at the lower end that operates to expand and contract in the thickness direction of the steel plate 5, a posture adjustment mechanism 17 that supports the welding torch 4 so that the angle can be adjusted by swinging it up and down, and a support bracket 37 that connects the operating part of the welding position adjustment mechanism 36 and the posture adjustment mechanism 17. The support bracket 37 supports the posture adjustment mechanism 17 so that its position can be adjusted in the X-axis direction, which is the extension direction of the groove.

The attitude adjustment mechanism 17 is a fan-shaped plate-like member with an arc-shaped through hole 17a that extends toward the rear side as it moves forward, and is configured so that a torch gripping part 38 that supports the welding torch 4 can be held at any position above the through hole 17a. The torch gripping part 38 may be configured so that the up and down swing position can be controlled by a motor or the like.

<Back copper plate support part>
The back copper plate support part 13 supports the back copper plate 12 arranged on the rear side of the welding carriage 2 on the back side of the steel plate 5. The back copper plate support part 13 has a back link support frame 41 configured to be detachable from the main body frame part 6 side,

attraction air cylinders

42, 42 as actuators that attract the back link support frame 41 to the back side of the steel plate 5, a back copper plate air cylinder 43 as an actuator that presses the back copper plate 12 against the back side of the steel plate 5, and a back link mechanism 44 operated by the back copper plate air cylinder 43.

The back copper plate 12 is a plate-shaped member with a pressure surface that contacts the back surface of the steel plate 5, and is generally equipped with a water-cooled cooling mechanism. In addition, the back copper plate 12 forms part of the slag bath by contacting the back surface of the steel plate 5, and in this state, the welding carriage 2 moves independently while performing welding work, allowing it to slide over the groove 10 while cooling the slag bath, etc.

As shown in Figures 3 and 4, the rear link support frame 41 is a pair of left and right plate-like members that extend in the front-rear direction along the travel direction of the welding cart 2 and are arranged on the rear side of the steel plate 5. A pull frame 45 that extends in a direction perpendicular to the extension direction, i.e., in the thickness direction of the steel plate 5, is attached and fixed to the middle part of the front-rear direction of the rear link support frame 41 so as to be clamped, thereby forming an overall T-shape. In addition, rear running rollers 46 consisting of a pair of left and right

rear front wheels

46A, 46A and a pair of left and right rear

rear wheels

46B, 46B are supported on the front and rear ends of the rear link support frame 41.

The attachment frame 45 is a plate-like member that extends from the front side to the back side of the steel plate 5 through the groove 10, which is the gap formed between the pair of

steel plates

5A, 5B. One end of the attachment frame 45 is attached to the main frame 6 side in a state in which it can be pushed and pulled along the extension direction via the

attachment air cylinders

42, 42. The other end of the attachment frame 45 is detachably pinned to the middle of the longitudinal direction of the back link support frame 41.

As shown in FIG. 5 etc., a pair of pulling air cylinders 42 are provided on the left and right sides at the rear between the pair of left and right body frames 18, 18 inside the body frame 6. The pair of pulling air cylinders 42 are configured so that a pair of operating rods supported facing upward in the vertical direction can be connected to the pulling frame 45 side via a connecting member 47.

In other words, the pull air cylinder 42 is configured so that the pull frame 45 is pulled up toward the welding carriage 2 placed on the surface of the steel plate 5 by extending the operating rod, thereby pressing the back running roller 46 provided on the back link support frame 41 against the back side of the steel plate 5.

As shown in Figure 4, the air cylinder 43 for the back copper plate is attached and fixed inside the main body frame 6 with the operating rod facing directly downward in the vertical direction via

cylinder support plates

48, 48 arranged to sandwich the head side on the left and right, and a pair of front and

rear fixing members

49, 50 that extend in the left-right direction to bridge the pair of

cylinder support plates

48, 48.

As shown in FIG. 4 etc., the air cylinder 43 for the back copper plate has an operating rod connected to one end of an L-shaped operating piece 51 that is pivotally supported on a fixed member 50 between a pair of

cylinder support plates

48, 48. A back link operating body 52 is provided on the other end of the operating piece 51, and the back link operating body 52 is configured to be able to operate the back link mechanism 44 by being pivoted forward and backward by the expansion and contraction of the air cylinder 43 for the back copper plate.

As shown in Figures 3 and 4, the rear link mechanism 44 has a rear drive link member 61 which is a driving link extending in the vertical direction, a rear driven link member 62 which is a driven link provided on the rear side of the link mechanism, and a rear intermediate link member 63 which is an intermediate link extending in the front-rear direction.

The rear drive link member 61 is a link member that extends vertically in front of the main frame 6 and the front wheels 7A. The lower side of the rear drive link member 61 is connected to the front end side of the rear link support frame 41 via the first connecting joint 57, and the further lower side is connected to the front end side of the rear intermediate link member 63 via the third connecting joint 59.

The rear driven link member 62 is a link member that is disposed on the rear side of the main frame portion 6 and on the rear side of the steel plate 5. The upper front end side of the rear driven link member 62 is connected to the rear end side of the rear link support frame 41 via the second connecting joint 58, and the lower front end side is connected to the rear end side of the rear intermediate link member via the fourth connecting joint 60.

The rear intermediate link member 63 is a link member that extends in the front-rear direction along the rear link support frame 41. The front end of the rear intermediate link member 63 is connected to the lower end of the rear driving link member 61, and the rear end is connected to the lower front end of the rear driven link member 62.

At this time, the distance between the third connecting section 59 and the fourth connecting section 60 on the rear intermediate link member 63 is formed to be approximately the same length as the distance between the first connecting section 57 and the second connecting section 58. The length between the first connecting section 57 and the second connecting section 58 can also be considered the length of the rear link support frame 41. In this way, the rear link mechanism 44 constitutes a four-section link with a closed loop structure formed in the shape of a parallelogram in side view.

Also, as shown in FIG. 4 etc., the rear drive link member 61 is integrally formed with the rear operation arm portion 61a by extending upward from the first connecting section 57, and the upper side of the rear operation arm portion 61a is configured to abut against the rear link operation body 52 operated by the rear copper plate air cylinder 43.

Also, as shown in Figures 3 and 4, the rear driven link member 62 is formed in a plate shape extending in the front-rear direction, and a notch 62a is formed on the upper rear side, and the rear copper plate 12 is supported by the notch 62a. As a result, the pressure surface of the rear copper plate 12 is supported parallel to the rear side of the steel plate 5, and the entire pressure surface is configured to abut against the rear side of the steel plate 5.

With the back side link mechanism 44 of this configuration, the operating force associated with the expansion and contraction operation of the back copper plate air cylinder 43 acts in the following order on the operating rod → back side link operating body 52 → back side operating arm part 61a → back side driving link member 61 → back side intermediate link member 63 → back side driven link member 62 and back copper plate 12, thereby allowing the back copper plate 12 to move up and down relative to the back side of the steel plate 5. Note that the actuator that operates the back side link mechanism 44 may be an electric cylinder or a motor instead of the back copper plate air cylinder 43.

In other words, with the above-mentioned back copper plate support part 13, the front and back surfaces of the steel plate 5 on which the groove 10 is formed can be firmly clamped between the running rollers 7 on the main frame part 6 side and the back running rollers 46 on the back link support frame 41 side, so that the welding carriage 2 in a vertical position suspended by the electric winch 3 can be held in a self-propelled state on the surface of the steel plate 5. In addition, it is possible to operate the pressure operation for pressing the back copper plate 12 against the back side of the steel plate 5 and the release of the pressure operation of the back copper plate 12.

<Guide roller>
The guide roller 8 is a tracing roller for guiding the welding carriage 2 so that the welding proceeding direction is along the extension direction of the groove 10, i.e., along the weld line, by being positioned in the groove 10 on the front side of the welding torch 4 that performs welding. More specifically, the guide roller 8 is positioned in the groove 10 so as to abut against the groove faces 5a and 5b of a pair of

steel plates

5A and 5B that form the groove 10. Note that the left groove face is 5a and the right groove face is 5b with respect to the direction in which the welding proceeds. A plurality of guide rollers 8 are provided along the extension direction of the groove 10. Note that, in the illustrated example, two guide rollers 8 are provided.

In this embodiment, the guide roller 8 has a fulcrum guide roller 8B and a movable guide roller 8A that is positioned forward of the fulcrum guide roller 8B. The fulcrum guide roller 8B is positioned in a front-to-rear position between the front wheels 7A and the rear wheels 7B, and is supported so that it can move up and down. The movable guide roller 8A is positioned in front of the welding cart 2, and is supported so that it can move left-right and up-down. The positions and number of guide rollers 8 are not limited to these, but it is preferable to position at least one in front of the welding cart 2.

As shown in FIG. 4, etc., the fulcrum guide roller 8B has a fulcrum roller shaft 66 that supports the fulcrum guide roller 8B, a pair of left and right fulcrum

roller support plates

67, 67 that are attached and fixed to both ends of the fulcrum roller shaft 66, and a pair of left and right fulcrum gas springs 68 that support the fulcrum roller support plates 67 so that they can be displaced in the vertical direction.

The fulcrum gas spring 68 is attached and fixed at its lower end to the fulcrum roller support plate 67, and at its upper end to a connecting rod 69 formed to bridge the pair of left and right main frames 18. This allows the fulcrum guide roller 8B to be elastically displaceable in the vertical direction, and is supported on the main frame 6 side in a configuration in which it is biased toward the inside of the groove 10.

As shown in Figures 4 and 6, the movable guide roller 8A is equipped with a movable roller support section that supports the movable guide roller 8A on the main body frame section 6 side so that the movable guide roller 8A can be displaced in the up and down direction, and a movable roller drive section that supports the movable guide roller 8A so that it can be driven in the left and right direction, and is configured so that the left and right position of the movable guide roller 8A can be controlled by the control section.

The movable roller support portion has a movable roller shaft 71 that supports the movable guide roller 8A, a pair of vertical oscillating frames 72, 72 that extend diagonally upward and rearward from the movable roller shaft 71 and are provided on either side of the movable roller shaft 71, and a pair of vertical

driving air cylinders

73, 73 whose operating rods face forward. At this time, the operating rod of the vertical driving air cylinder 73 is connected to the base end side of the vertical oscillating frame 72 via a vertical linking rod 74, so that it is possible to urge the vertical oscillating frame 72 downward.

With this configuration, the movable guide roller 8A is supported on the main body frame 6 side so as to be able to swing up and down, and the force of the vertical drive air cylinder 73 can be used to bias the movable guide roller 8A so as to press it against the groove 10 side. In addition, the movable guide roller 8A is configured to be able to slide left and right on the movable roller shaft 71 between a pair of left and right vertical swing frames 72, 72. Details will be explained below.

The movable roller drive unit includes a pair of left and right

drive air cylinders

75, 75 that are provided on the left and right outer sides of the movable roller shaft 71 at the front end of the vertically oscillating frame 72 and serve as a pair of left and right drive means that enable the movable guide roller 8A to slide on the movable roller shaft 71, and the above-mentioned control unit that controls the drive of the left and right drive air cylinders 75. As shown in FIG. 6 etc., in this embodiment, the movable roller drive unit is configured to be able to control the drive thrust of the left and right drive air cylinders 75 via the left and right drive unit air circuit controlled by the control unit. Note that the actuator that slides the movable guide roller 8A is not limited to the left and right drive air cylinders 75, and an electric cylinder or a motor may also be used.

The drive air circuit will be described with reference to Figure 7. Figure 7 is a diagram showing the configuration of the drive air circuit. As shown in the figure, the drive air circuit includes left and right

drive air cylinders

75, 75, a meter-in flow control valve 76, a directional control valve (three positions, exhaust center) 77, and an electro-pneumatic regulator 78. Note that the configuration of the drive air circuit is not limited to the above, and it may be configured without the flow control valve 76.

Specifically, when the movable guide roller 8A is slid to the right, the drive air circuit switches the directional control valve 77 and passes air through the electro-pneumatic regulator 78 and flow control valve 76 to fill the head side of the left-side horizontal driving air cylinder 75 and the rod side of the right-side horizontal driving air cylinder 75 with air, and exhausts the air from the rod side of the left-side horizontal driving air cylinder 75 and the head side of the right-side horizontal driving air cylinder 75. Similarly, when the movable guide roller 8A is slid to the left, the directional control valve 77 switches and passes air through the electro-pneumatic regulator 78 and flow control valve 76 to fill the rod side of the left-side horizontal driving air cylinder 75 and the head side of the right-side horizontal driving air cylinder 75 with air, and exhausts the air from the head side of the left-side horizontal driving air cylinder 75 and the rod side of the right-side horizontal driving air cylinder 75.

In addition, as shown in FIG. 7, the drive air circuit can be switched to a state in which air is discharged from both the rod side and head side of the left and right drive air cylinders 75, allowing the movable guide roller 8A to enter a free state in which it can move freely in parallel in the left and right direction on the movable roller shaft 71.

When the control unit detects a misalignment between the welding proceeding direction of the welding carriage 2 during welding operation and the extension direction of the groove 10 that is equal to or greater than a preset threshold value using the visual sensor 14, which will be described in detail later, the control unit adjusts the sliding position of the movable guide roller 8A via the left and right driving air cylinders 75 so that the welding carriage 2 rotates in the direction that reduces the detected misalignment. On the other hand, when the misalignment detected by the detection sensor is less than the preset threshold value, the control unit is configured to be able to execute drive control so that the movable guide roller 8A is in a free state in which it can move freely in parallel in the left and right direction by discharging air from the rod side and head side of the left and right left and right driving air cylinders 75. A specific control method for the drive control will be described later.

<Visual sensor>
The visual sensor will be specifically described with reference to Figures 1 to 8. Figure 8(A) is a model diagram in which a reference position and a current position are photographed by the visual sensor, Figure 8(B) is a model diagram showing a state in which the visual sensor detects that the amount of deviation is less than a threshold, and Figure 8(C) is a model diagram showing a state in which the visual sensor detects that the amount of deviation is equal to or greater than the threshold.

In this embodiment, a visual sensor 14 that captures an image of the welding area is used as a detection sensor that detects the amount of misalignment of the welding direction of the welding carriage 2 relative to the extension direction of the groove 10 extending in the X-axis direction, i.e., the weld line. As shown in Figures 3 and 4, the visual sensor 14 is installed along the inside of the groove 10 by being attached to the rear connecting rod 20 that constitutes the main body frame 6. Therefore, the visual sensor 14 is configured to be able to detect the amount of misalignment between the welding direction of the welding carriage 2 and the extension direction of the groove 10 extending in the X-axis direction, i.e., the weld line, by capturing an image 80 that always includes the slag bath, which is the welding area, in its angle of view while the welding carriage 2 is traveling upward on the surface of the steel plate 5 while performing welding work.

Specifically, first, before starting the welding operation, the welding cart 2 is fixed to the steel plate 5 side so that it is not tilted left or right with respect to the weld line, i.e., in the yaw angle direction, and the mounting position of the visual sensor 14 is adjusted so that the slag bath is located in the center of the captured image 80. Next, as shown in FIG. 8(A), the shape X of the slag bath is analyzed from the image 80 captured by the visual sensor 14, and the center of gravity of the shape X of the slag bath is obtained as the reference position Y. The shape X of the slag bath is approximately the same as the shape of the groove 10. The reference position Y is not limited to the center of gravity of the slag bath and may be set to any position. At this time, the visual sensor 14 is installed so that the reference position Y and the center position C of the image 80 overlap.

Next, as shown in Figures 8(B) and (C), after the start of welding work, if the reference position Y of the slag bath in the image 80 captured by the visual sensor 14 shifts left or right from the center position C of the image 80 representing the current position of the welding carriage 2, the amount of shift can be detected as the amount of shift in the welding progress direction of the welding carriage 2 relative to the weld line, i.e., the amount of yaw angle displacement. In other words, the amount of shift is detected based on the difference between the reference position Y of the slag bath and the center position C of the image representing the current position of the welding carriage 2.

At this time, a frame T indicating the above-mentioned threshold value used in drive control may be displayed within the image 80 acquired by the visual sensor 14. In this case, as shown in FIG. 8(C), if the reference position Y goes outside the frame T during welding work, the amount of deviation exceeds the threshold value, and the worker can intuitively grasp the amount of deviation. Note that the size of the frame T within the image 80 varies depending on the threshold value that is set.

The detection sensor for detecting the amount of misalignment is not limited to the visual sensor 14 described above, as long as it is capable of detecting the amount of displacement of the welding progress direction of the welding carriage 2 relative to the extension direction of the groove 10, specifically the amount of yaw angle displacement. The detection sensor may be an optical sensor such as a laser sensor, a magnetic sensor, a gyro sensor, or a combination of these.

<Control method>
Next, specific processing contents of the drive control by the control unit will be described with reference to Figures 9(A) to (D) and 10. The control unit is, for example, a part of a processor, and is a control device that controls the reading and writing of the arithmetic unit and the storage device, input and output, etc., and is connected to the visual sensor 14 on the input side, and to the directional control valve 77 and the electro-pneumatic regulator 78 on the output side.

The drive control will be outlined with reference to Figures 9(A) to (D), which are schematic diagrams showing the effect of the drive control. When the welding work is started in which the welding carriage 2 travels upward on the steel plate 5 while welding, as shown in Figure 9(A), the control unit starts to detect the amount of deviation between the welding progress direction of the welding carriage 2 and the extension direction of the groove 10 using the visual sensor 14, and if the amount of deviation is less than a threshold value, the movable guide roller 8A is set in a free state and the welding work continues.

Figure 9 (B) shows a case where the visual sensor 14 detects that the welding progress direction of the welding carriage 2 is tilted to the left of the extension direction of the groove 10, i.e., in the direction approaching the steel plate 5A, during welding operation, and that the amount of deviation is greater than or equal to a threshold value. In this case, as shown by the arrow in Figure 9 (C), the drive of a pair of left and right

drive air cylinders

75, 75 is controlled to slide the movable guide roller 8A so as to press against the groove surface 5a to the left where the deviation has occurred.

As a result, as shown in FIG. 9(D), the welding carriage 2 rotates to the right, which is the opposite direction to the sliding direction of the movable guide roller 8A, with the fulcrum guide roller 8B in the groove 10 as the fulcrum, due to a reaction from the left groove surface 5a pressed by the movable guide roller 8A. In other words, the welding carriage 2 rotates in a direction in which the welding proceeds along the extension direction of the groove 10. That is, the welding carriage 2 can correct the amount of deviation detected by the visual sensor 14 by returning the traveling direction of the welding carriage 2, which has begun to deviate from the extension direction of the groove 10, to the traveling direction along the extension direction of the groove 10. Note that "correcting the amount of deviation" in this case may also be rephrased as "canceling the amount of deviation."

With this configuration, when the welding carriage 2 is undergoing welding work, various working conditions and disturbances, such as differences in the thickness of the

steel plates

5A and 5B that form the groove, differences in the thickness at the plate joint, inclination, or a misalignment between the left and right positions of the groove 10, cause a misalignment between the welding progress direction of the welding carriage 2 and the weld line, and when the visual sensor 14 detects this misalignment, the left and right

drive air cylinders

75, 75 can perform drive control to press the groove surfaces 5a, 5b on one side with the movable guide roller 8A so that the welding carriage 2 moves in a direction that cancels the detected misalignment.

Next, the process flow of the drive control will be described with reference to FIG. 10. FIG. 10 is a flow diagram showing the drive control process. When the drive control process is started, the control unit proceeds to step S1. In step S1, the visual sensor 14 detects the amount of deviation between the welding progress direction of the welding carriage 2 and the extension direction of the groove 10, and the process proceeds to step S2.

In step S2, it is confirmed whether the amount of misalignment detected by the visual sensor 14 is equal to or greater than a preset threshold, and if it is determined that the amount of misalignment detected is equal to or greater than the threshold, the process proceeds to step S3.

In step S3, the control unit calculates the air pressure required to drive the left and right driving air cylinders 75 to correct the amount of misalignment based on the detected amount of misalignment, and drives the pair of left and right driving

air cylinders

75, 75 based on the calculated air pressure. This causes the movable guide roller 8A to slide left and right, pressing against the groove surface (either groove surface 5a or groove surface 5b) in the direction in which the amount of misalignment was detected. Then, the process returns.

As a result, the welding carriage 2 is pushed back in the opposite direction to the sliding direction of the movable guide roller 8A, with the fulcrum guide roller 8B in the groove 10 as the fulcrum, and the welding carriage 2 can be rotated in a direction that reduces the amount of misalignment. By continuing this until the amount of misalignment detected by the visual sensor 14 falls below the threshold value, the welding progress direction of the welding carriage 2 can be returned to the correct position along the weld line.

As a method of calculating the air pressure to drive the left and right driving

air cylinders

75, 75, a database may be created in advance of the relationship between the detected amount of misalignment and the air pressure required to correct the amount of misalignment, and the air pressure to be supplied to the pair of left and right driving

air cylinders

75, 75 may be determined based on the database and the value of the detected amount of misalignment. Also, the air pressure and data on the degree of misalignment correction may be recorded and automatically learned, or the air pressure may not be calculated and the left and right driving air cylinders 75 may always be driven with a constant air pressure.

If it is determined in step S2 that the amount of deviation detected by the visual sensor 14 is less than a preset threshold, the process proceeds to step S4.

In step S4, the horizontal driving air cylinder 75 does not slide the movable guide roller 8A, and the air is discharged from both the head side and rod side of the horizontal driving air cylinder 75, in other words, the movable guide roller 8A switches to a guide roller free state in which it can move freely in parallel in the horizontal direction on the movable roller shaft 71, and then returns. As a result, even if the movable guide roller 8A is subjected to a disturbance such as contact with a point where the left-right position of the groove changes suddenly, such as when joining upper and lower plates, the movable guide roller 8A escapes in the horizontal direction, thereby avoiding a sudden yaw change to the welding cart 2.

The present invention is not limited to the above-described embodiment, and it is intended that the various components of the embodiment may be combined with each other, and that those skilled in the art may modify and apply the invention based on the description in the specification and well-known technology, and this is included in the scope of the protection sought.

As described above, the present specification discloses the following:
(1) A vertical welding device for performing welding in a vertical position on a groove formed by two workpieces,
A welding carriage that welds one surface side perpendicular to the plate thickness direction of the welded material while traveling along the groove, and a welding torch mounted on the welding carriage,
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove;
A detection means for detecting a deviation amount of the welding proceeding direction of the welding carriage with respect to an extension direction of the groove;
having
At least one of the guide rollers is a movable guide roller that can be moved in parallel in a direction perpendicular to the welding proceeding direction by a driving means,
The vertical welding device is characterized in that the driving means performs drive control to press the movable guide roller against the groove surface so that the movable guide roller moves in a direction that cancels the amount of deviation detected by the detection means.
According to this configuration, in a self-propelled vertical welding device that does not require the installation of rails, the posture of the welding carriage can be stably maintained to suppress deviation of the welding torch tip position, thereby ensuring good welding quality.

(2) The vertical welding apparatus according to (1), wherein the detection means sets a threshold value in advance for the amount of deviation, and when it is detected that the amount of deviation is equal to or greater than the threshold value, performs the drive control, and when it is detected that the amount of deviation is less than the threshold value, makes the movable guide roller freely movable in parallel in a direction perpendicular to the welding proceeding direction.
According to this configuration, the movable guide roller is driven and controlled only when the amount of deviation is equal to or greater than a threshold value, so that accuracy can be improved without reducing the work efficiency of welding work in a vertical position as much as possible.

(3) The detection means
At least one sensor among a visual sensor, an optical sensor, and a magnetic sensor is included;
The vertical welding apparatus according to claim 1 or 2, characterized in that the amount of deviation is detected based on a difference between a predetermined reference position acquired by the sensor and a current position of the welding carriage.
According to this configuration, the amount of deviation between the traveling direction of the welding carriage and the extension direction of the groove can be detected easily and accurately.

(4) The vertical welding apparatus according to any one of (1) to (3), characterized in that the guide roller disposed furthest forward in the welding proceeding direction among the guide rollers is the movable guide roller.
According to this configuration, by arranging the movable guide roller that is driven in the left-right direction at the frontmost position, the operation of correcting deviation of the welding carriage in the welding proceeding direction can be smoothly performed.

(5) A hanging type vertical welding device,
The vertical welding apparatus according to any one of (1) to (4), further comprising an electric winch for hoisting the welding carriage.
According to this configuration, the size and weight of the entire device can be made compact, and the preparation steps before starting work are relatively simple, improving maintainability and work efficiency.

(6) A vertical welding device for electroslag welding or electrogas welding,
The welding carriage includes:
A front copper plate is arranged on a front surface side, which is one surface of the material to be welded, and slides along the groove;
A back copper plate is arranged on the back side, which is the other side of the welded material, and slides along the groove;
a link mechanism that operates the front copper plate and the back copper plate in a direction to clamp the workpiece;
The vertical welding apparatus according to any one of (1) to (5), further comprising an actuator for controlling the link mechanism.
According to this configuration, the front copper plate and the back copper plate that clamp the material to be welded can be accurately manipulated with a relatively simple structure.

(7) The vertical welding apparatus according to (2), characterized in that the driving means is an air cylinder that moves the movable guide roller in a parallel manner, and the apparatus is configured to calculate an output of the air cylinder based on the amount of deviation detected by the detection means.
According to this configuration, it is possible to easily calculate the output of the air cylinder required to correct the amount of deviation.

(8) A control method for a vertical welding apparatus for performing welding in a vertical position on a groove formed by two workpieces, comprising:
The vertical welding apparatus includes a welding carriage that welds one surface side perpendicular to the plate thickness direction of the workpiece while traveling along the groove, and a welding torch mounted on the welding carriage;
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove,
At least one of the guide rollers is a movable guide roller that is movable in parallel in a direction perpendicular to the welding proceeding direction,
a movable guide roller that presses the groove surface in a direction in which the amount of deviation is detected when a deviation of the welding carriage in the welding proceeding direction with respect to an extension direction of the groove is detected.
According to this configuration, in a control method for a self-propelled vertical welding device that does not require the installation of rails, the posture of the welding carriage can be stably maintained and deviation of the welding torch tip position can be suppressed, thereby ensuring good welding quality.

Although various embodiments have been described above, it goes without saying that the present invention is not limited to these examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components in the above embodiments may be combined in any manner as long as it does not deviate from the spirit of the invention.

This application is based on a Japanese patent application (Patent Application No. 2022-158260) filed on September 30, 2022, the contents of which are incorporated by reference into this application.

2 Welding cart 3 Electric winch 4 Welding torch 8A Movable guide roller (guide roller)
8B Support guide roller (guide roller)
9 Front copper plate 12 Back copper plate 14 Visual sensor (detection means)
15 Control unit 24 Air cylinder (actuator) for front copper plate
25 Front link mechanism (link mechanism)
43 Air cylinder for back copper plate (actuator, air cylinder)
44 Back side link mechanism (link mechanism)
75 Left and right drive air cylinder (drive means, air cylinder)

Claims

A vertical welding device for performing welding in a vertical position on a groove formed by two workpieces,
A welding carriage that welds one surface side perpendicular to the plate thickness direction of the welded material while traveling along the groove, and a welding torch mounted on the welding carriage,
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove;
A detection means for detecting a deviation amount of the welding proceeding direction of the welding carriage with respect to an extension direction of the groove;
having
At least one of the guide rollers is a movable guide roller that can be moved in parallel in a direction perpendicular to the welding proceeding direction by a driving means,
The vertical welding device is characterized in that the driving means performs drive control to press the movable guide roller against the groove surface so that the movable guide roller moves in a direction that cancels the amount of deviation detected by the detection means.
2. The vertical welding apparatus according to claim 1, wherein the detection means sets a threshold value for the amount of deviation in advance, and when it is detected that the amount of deviation is equal to or greater than the threshold value, the detection means performs the drive control, and when it is detected that the amount of deviation is less than the threshold value, the detection means makes the movable guide roller freely movable in parallel in a direction perpendicular to the welding progress direction.
The detection means includes:
At least one sensor among a visual sensor, an optical sensor, and a magnetic sensor is included;
3. The vertical welding apparatus according to claim 1, wherein the amount of deviation is detected based on a difference between a predetermined reference position and a current position of the welding carriage, the difference being acquired by the sensor.
The vertical welding apparatus according to claim 1 or 2, wherein the guide roller disposed furthest forward in the welding proceeding direction among the guide rollers is the movable guide roller.
A hanging type vertical welding device,
3. The vertical welding apparatus according to claim 1, further comprising an electric winch for hoisting the welding carriage.
A vertical welding apparatus for electroslag welding or electrogas welding, comprising:
The welding carriage includes:
A front copper plate is arranged on a front surface side, which is one surface of the material to be welded, and slides along the groove;
A back copper plate is arranged on the back side, which is the other side of the welded material, and slides along the groove;
a link mechanism that operates the front copper plate and the back copper plate in a direction to clamp the workpiece;
The vertical welding apparatus according to claim 1 or 2, further comprising: an actuator for controlling the link mechanism.
3. The vertical welding device according to claim 2, wherein the driving means is an air cylinder that moves the movable guide roller in a parallel manner, and the output of the air cylinder is calculated based on the amount of deviation detected by the detection means.
A method for controlling a vertical welding apparatus for performing welding in a vertical position on a groove formed by two workpieces, comprising:
The vertical welding apparatus includes a welding carriage that welds one surface side perpendicular to the plate thickness direction of the workpiece while traveling along the groove, and a welding torch mounted on the welding carriage;
The welding carriage includes:
At least two or more guide rollers are arranged in a line along the welding proceeding direction and proceed along the extension direction of the groove,
At least one of the guide rollers is a movable guide roller that is movable in parallel in a direction perpendicular to the welding proceeding direction,
a movable guide roller that presses the groove surface in a direction in which the amount of deviation is detected when a deviation of the welding carriage in the welding proceeding direction with respect to an extension direction of the groove is detected.