JPH0683898B2 - Self-propelled welding robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a self-propelled welding robot for butt and fillet of ships, bridges, nuclear power, pressure vessels and the like.

[Conventional technology]

An automatic welding machine is known in which a welding torch is mounted on a welding carriage so that the surface of an iron plate can be welded while self-propelled. That is, as shown in FIG. 5, there is known a structure in which a welding torch (c) is mounted on a welding carriage (a) capable of traveling by adsorbing the wheel (b) as a magnet wheel on an iron plate surface.

Such a known welding machine is capable of traveling horizontally, vertically and laterally without a traveling rail on a flat plate surface.

However, the welding torch (c) is not correctly located at the welding point where the traveling surface is large and has a mating plate surface and there are undulations (d) and protrusions (e) as shown in FIG. , Cannot be automatically welded. For example, as shown in the figure, when the welding carriage (a) comes to the convex portion (e), the bottom of the carriage (a) contacts the convex portion (e), but the front wheel (b) floats above the iron plate surface. Since the welding carriage (a) is in a loose state, it cannot run on the convex portion. Further, conventionally, a welding carriage which has a mechanism for keeping a constant angle (f) and a position (g) with the plate surface along the weld plate surface and which is capable of moving up and down the traveling surface (h) has been conventionally used. not exist.

Therefore, conventionally, automatic welding of welded joints such as fillet welding and butt welding at locations where the welding torch does not reach the welding location and the torch angle is not constant can be performed. Nakatsuta.

[Problems to be solved by the invention]

Conventionally, a welded joint of a structure having an uneven portion cannot continuously weld at the uneven portion. In particular, as the structure, when the vehicle continuously travels on the uneven portion, the bottom of the bogie hits the convex portion, and in the concave portion, there is no mechanism for the torch to follow up to the welded portion, which makes automatic welding difficult.

The present invention is intended to provide a welding robot capable of performing automatic welding while easily traveling even in a place where automatic welding has been difficult in the past and achieving labor saving.

[Means for solving problems]

According to the present invention, a trolley having wheels that can be moved up and down even on an inclined surface by using permanent magnets is provided with two vertical shafts provided movably in the vertical direction, and one of the two vertical shafts is provided with a horizontal direction above the vertical shaft. And a rotary shaft for connecting the welding torch so that the welding torch moves in an arc around the tip of the welding torch, and the two vertical shafts. At the lower end of the other vertical axis of the other, a vertical sensor for detecting the distance to the plate surface and a traveling surface inclination sensor with respect to the plate surface as viewed from the truck are provided, and a vehicle body inclination sensor and a traveling line sensor are installed on the truck, respectively. Even if the welding surface is uneven in a butt shape due to the oscillating function of the left and right shafts and one vertical shaft that supports the left and right shafts so that the left and right shafts can move left and right, and the positioning of the welding torch tip by each sensor. So as to automatically modeled after the along connexion welding torch tip surface.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the welding robot of the present invention in principle.
As shown in FIG. 2, a welding torch (7) is attached to a carriage including a vehicle body (1), a mounting portion (2), and front, rear, left and right wheels (3) (4) (5) (6) which are permanent magnets. Is attached swingably, and the welding surface is detected by the sensor while moving up and down the traveling surfaces (C), (D) and (E) having the convex portion (A) and the concave portion (B) in the state where the flat plates are butted against each other. By doing so, the torch angle of the welding torch (7) can be properly maintained.

More specifically, as shown in FIG. 1, the vehicle body (1) of the truck has drive shafts (8) and (9) extending in the front-rear direction of the truck arranged in parallel with the left and right as separate systems so that both drive systems can be driven. Axis (8)
Gear parts (10) (11), (12) (1
3) is provided, the right and left front and rear gears (10) and (11) are connected to the right and left front and rear wheels (3) and (4) respectively, and the left and right front and rear gears (12) and (13) are connected. Similarly, the left and right front wheels (5) and (6) are connected to each other, and the left and right drive shafts (8) and (9) are separately rotated by a motor (not shown) so that the right and left wheels (3) are rotated. (4), (5) and (6) are set to be constant speed and different speed so that straight traveling, left traveling and right traveling can be arbitrarily performed. A vertical axis (1
4) is movably supported in the vertical direction, and is vertically guided by the vertical shaft (14) to move in the vertical direction, and at the same time, supports the vertical shaft (15) having an oscillating function, and further the vertical shaft (15). The horizontal left and right shaft (16) having an oscillating function so that it can be freely moved in the left and right direction and can be vertically displaced together with the vertical shaft (15) is supported by the mounting portion (2) and The shafts (14), (15), and the left and right shafts (16) are independently moved in respective axial center directions by a drive motor (not shown). Further, a rotating shaft (17) supported so as to move the welding torch (7) in an arc shape around the tip of the welding torch (7) is connected to one end of the left and right shafts (16), and the welding torch is connected. A predetermined angle (torch angle) is maintained between (7) and the vertical axis (14). Further, on the outer side of the wheels (3) and (4) of the truck, a sensor (18) before the running line and a sensor (19) after the running line are provided.
A body tilt sensor (20) for detecting the tilt of the vehicle body is provided on the body part (1), and the vertical axis (1
At the lower end of 4), a vertical sensor (21) for detecting the plate surface on which the truck travels is provided, and at the portion of this vertical sensor (21), a traveling surface inclination sensor (22) with respect to the plate surface as seen from the truck is provided. .

The above vertical sensor (21), running surface inclination sensor (22),
The running line sensors (18) and (19) are of roller type so that they are energized when the rollers come into contact with the plate surface or the guide surface. The vertical sensor (21) is a vertical sensor when the vertical axis (14) is pushed down. When (14) detects the plate surface, the signal stops the motor on the vertical axis (14). At this time, the running surface tilt sensor (22) detects the tilt and the potentiometer (converts the rotation angle into an electrical resistance value). The angle of inclination can be detected by (). The travel line sensors (18) (19) detect when the truck meanders while traveling and regulate the course of the truck.

When running the welding robot of the present invention on a running surface,
The right and left front wheels (3) and (4) are simultaneously rotated by the rotation of the drive shaft (8), and the left and right front wheels (5) and (6) are also simultaneously rotated independently. If the rotation speeds of the right and left wheels (3), (4), (5) and (6) by the drive shafts (8) and (9) are made equal, the carriage can go straight and the right wheel (3).
If the rotation speed of (4) is set to be higher than that of the left wheels (5) and (6), the vehicle can move to the left, and conversely, the rotation speed of the left wheels (5) and (6) can be changed to the right wheel (3) ( If it is larger than that of 4), the vehicle can move to the right, so that the direction can be freely changed by arbitrarily controlling the rotational speeds of the left and right drive shafts 8 and 9. This direction change instruction is obtained from a detection signal from the traveling line sensors (18) (19) provided on the side.

At the time of welding, it is necessary to properly position the tip of the welding torch (7) on the welding surface, but when there are convex portions (A) and concave portions (B) on the traveling surface as shown in FIG. , The welding torch (7) following the convex portion (A) and the concave portion (B)
It is necessary to move the tip.

An example of fillet welding and butt welding of a running surface having a convex portion (A) and a concave portion (B) with the welding robot of the present invention will be described below.

3 and 4 show a running surface (D) having a recess (B).
(E) shows a case where fillet welding is performed at the intersection of the traveling surface (D) and the member (F) arranged at right angles to the traveling surface (D). ), The vertical shaft (14) is lowered by the drive motor in the direction perpendicular to the vehicle body (1), and the vertical sensor (21) is moved to the running surface (D).
And the traveling surface inclination sensor (22) detects the inclination of the traveling surface (D). The traveling surface inclination sensor (22) is mounted on an axial extension of the vertical sensor (21) and detects the inclination of the traveling surface as viewed from the vertical axis (14). Running surface tilt sensor (22)
The tilt angle is detected by the potentiometer based on the signal detected in.

Distance between the traveling surface (D) and the bogie body, traveling surface (D)
When the tilt angle of the vehicle body is detected, the vertical axis (15)
Lower right from the bottom of the. This vertical axis (15)
Has a function of oscillating the welding torch (7) in the vertical direction, which is particularly necessary for welding. This oscillating is important for welding because it widens and shapes the shape of the weld bead.

When the vertical shaft (15) is lowered, the left and right shafts (16) are integrally displaced downward, and the tip position of the welding torch (7) is brought closer to the running surface (D). The welding torch (7) is connected to the left and right shafts (1
Since it is connected to 6), the welding torch (7) is moved in an arc by the rotating shaft (17) in combination with the oscillation by the vertical shaft (15) and the left and right shafts (16), and the welding torch (7) is moved.
Hold the torch angle (23). In FIG. 3, (24) is a welding bead, and the front end of the bogie moves on the traveling surface (E) as the welding progresses, so that the body part (1) of the bogie and the traveling surface (D) form it. Since the angle changes every moment, the vertical axis (15), the horizontal axis (16) are adjusted and the rotary axis (17) is controlled by utilizing the vertical sensor (21) and the traveling surface inclination sensor (22) each time. Always welding torch (7)
To maintain the desired torch angle.

As the fillet welding on the running surface (D) progresses as shown in FIG. 3, the running surface (E) passes through the recess (B) as shown in FIG.
And the welding of the intersection of the member (F). As shown in FIG. 4, when the tip of the welding torch (7) passes through the recess (B), the rotating shaft (17) is operated to move the welding torch (7) in an arc around the tip, and So that the proper torch angle (23) is maintained. (25) is the bottom surface of the vehicle body (1).

Next, running surfaces (C) and (D) having uneven portions as shown in FIG.
An example in which the welding robot of the present invention is applied to (E) will be described.

Convex part: 30 degree Concave part: 105 degree Length of running surface (C): 300 mm Length of running surface (D): 500 mm Length of running surface (E): 500 mm (14) (15) (16) (17)
The effective moving length of the front wheel (3)
When the distance between (5) and the rear wheels (4) and (6) is 200 mm, the vertical axis (14) has an upper 10 mm, the lower 110 mm has a vertical axis (15), the upper 10 mm has a lower 10 mm, and the left and right axes (16) have It was confirmed that the welding torch (7) satisfying each dimension in Fig. 2 can be guided by setting the front shaft 45 ° and the rear shaft 45 ° on the rotating shaft (17) with the right 10 mm and the left 10 mm.

The rotating shaft (17) for moving the welding torch (7) in an arc around its tip is a parallelogram link (26) in FIGS. 3 and 4, and the welding torch (26) is attached to the horizontal link of the link mechanism. 7) is supported so that the welding torch (7) moves in an arc around the tip by the parallelogram movement of the link (26) and the rotation around the vertical axis (14), and the horizontal link is always moved along the vertical axis ( Although the case where it is formed at a right angle to 14) has been shown, it is needless to say that the present invention is not limited to this and that other changes can be made without departing from the scope of the present invention.

〔The invention's effect〕

As described above, according to the welding robot of the present invention, the following excellent effects can be obtained.

(I) Since the tip of the welding torch can be correctly positioned on the welding surface even in the concave and convex portions of the traveling surface, the iron plate surface, which could not be conventionally automatically welded, has a large traveling surface, and the fillet of the concave portion and the convex portion having the mating plate surface. Welding is possible.

(Ii) Since there is a mechanism in which the height of the torch is constant with respect to the plate surface along the ups and downs, and a constant angle is always maintained with respect to the plate surface, good welding can be performed.

(Iii) The traveling direction of the welding carriage can be constantly corrected by the sensor that follows the welding line.

(Iv) The inclination of the welding arc point viewed from the horizontal line of the welding surface can be easily detected by calculating the signals of the inclination sensor of the carriage and the inclination sensor of the traveling surface in the carriage.

(V) It can also be used for welding TIG, MAG, submerge, etc. by changing the welding torch.

(Vi) Compact and lightweight, good workability, and labor saving.

[Brief description of drawings]

FIG. 1 is a view showing in principle the mechanism of the welding robot of the present invention, FIG. 2 is an example applied to welding of a traveling surface having irregularities, and FIGS. 3 and 4 show a portion near the concave portion of the traveling surface. Explanatory drawing which shows the attitude | position of the welding torch at the time of welding, FIG. 5 is a side view of the conventional automatic welding machine. (1) is a vehicle body part, (2) is a mounting part, (3) (4) (5)
(6) wheels, (7) welding torch, (8) and (9) drive shafts, (14) and (15) vertical shafts, (16) left and right shafts, (17)
Is a rotating shaft, (18) and (19) are running line sensors, (21) is a vertical sensor, and (22) is a running surface inclination sensor.

Claims (1)

[Claims] 1. A dolly having front and rear, left and right wheels as a magnet wheel, which is capable of self-propelling and moving up and down an inclined surface, is provided with two vertical shafts, each of which is vertically movable by a separate drive device. One of the vertical shafts has an oscillating function, and horizontal left and right shafts are movably held on the upper part of the shafts in the left and right directions, and the welding torch is centered on the tip of the welding torch at one end of the left and right shafts. It is characterized in that a rotating shaft for swinging is connected, a traveling line sensor is further provided on the side of the bogie, and a vertical sensor and a traveling surface inclination sensor are provided at the lower end of the other vertical shaft of the vertical shafts. Self-propelled welding robot that does.