JPH10296491A - Positioning method for square tube welding surface in welding member to square tube and positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning method for a square tube welding surface capable of executing suitable welding work in the case of welding a member to the square tube and the positioning device capable of executing the method. SOLUTION: A horizontally placed square tube 15 is rotatably supported at both end sides, at least one side of supporting shaft 21 is connected with a rotation driving device 30 via a clutch 40, the square tube 15 is rotated 90 degrees around the axial center with the rotation driving device 30, thereafter the rotating attitude is slightly regulated and positioned so that the pressing surface becomes parallel to the transferring direction of a welding torch T by releasing in the required time of driving/connecting to the supporting shaft 21 with the clutch device 40 and pressing to the upper surface 18 or back surface of the square tube 15 surface with the pressing member provided with the reference part parallel to the transferring direction of the welding torch T, and then automatic welding is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for positioning a welded surface of a square pipe when welding a member to an end or a side face of a square pipe (also called a square steel pipe) using a robot welding machine. About.

[0002]

2. Description of the Related Art As a kind of general prefabricated building, a unit building using a rectangular parallelepiped building unit is provided. This building unit consists of four pillars made of steel standing at the four corners, and the upper and lower ends of the pillars are connected by beams, respectively, to form a hexahedron. It is manufactured in a factory in advance and transported to the construction site by truck. Then, the required number is arranged side by side and stacked using a crane or the like to construct a building.

The hexahedral column is formed of a square tube, and connection members for connecting beams are welded to both ends of the square tube. As a method of welding the connection member to the square pipe, the connection member is temporarily welded to both ends of the square pipe in advance. In addition, holes are provided on both end surfaces of the connection member such that when the column is mounted on the square tube support device, the axis of the support device and the axis of the square tube are coaxial. Next, the square tube is placed horizontally on a base used for main welding, a support pin of a supporting device is inserted into a hole of the joint member, and one side of the square tube serving as a welding surface with the joint member faces upward. In addition, the welding torch is welded to the member while moving the welding torch on the upper surface of the square tube so as to be parallel to a predetermined moving direction of the robot welding machine. afterwards,
The square tube is rotated 90 degrees by a rotary drive device such as an electric motor so that the other welding surface between the connection member and the square tube faces upward, and the welding torch is again placed on a new upper surface of the square tube. (Weld surface), the welding is performed between the connection member and a new upper surface (weld surface) of the square tube, and the rotation of the square tube, the movement of the welding torch and the welding are sequentially repeated as necessary. Each side of the pipe is welded to the connection member.

However, the cross-sectional shape of the square tube is not exactly a square or a rectangle, but is often a parallelogram due to slight variations occurring at the four corners. Therefore, when the square tube is rotated by 90 degrees, the upper surface (welding surface) of the square tube and the welding torch moving surface do not become parallel, and the welding torch and the upper surface of the square tube (welding surface) when the welding torch moves. There is a possibility that proper welding cannot be performed due to a change in the interval and a change in the voltage and current.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been proposed in view of the above problems, and a method of positioning a welding surface of a square tube capable of appropriately welding members to the square tube, and
It is an object of the present invention to provide a positioning device capable of performing the method effectively and economically.

[0006]

There are two inventions proposed here. The first invention is a method of positioning a welding surface of a square tube when welding a member to the square tube, and the second invention Is a device for positioning a welding surface of a square tube, which preferably implements the above method. The method of positioning the welding surface of the square tube when welding the member to the square tube is to support the square tube horizontally and move the welding torch of the robot welding machine in the predetermined direction on the upper surface side of the square tube to weld the member. Then, after rotating the square tube 90 degrees about its axis and positioning the square tube, the welding torch is moved in a predetermined direction on a new upper surface to perform welding with a member. When the member is automatically welded to the square tube by repeating the rotation and welding of the horizontal tube, the laterally mounted square tube is rotatably supported at both ends thereof, and at least one of the support shafts is connected to a rotation driving device via a clutch device. Then, after the square tube is rotated by 90 degrees about the axis thereof by the rotation drive device, the clutch device is released when necessary from the drive connection to the support shaft, and the reference portion parallel to the moving direction of the welding torch. Pressing equipment with By the upper surface or lower surface of the pressing of the angle tube surface in, characterized by a rotational position such that the pressing surface is parallel to the reference part to fine tune the positioning.

On the other hand, the positioning device rotates the horizontal tube at 90 degrees about its axis, and moves the welding torch of the robot welding machine in a predetermined direction on the upper surface of the square tube to perform welding with the member. An apparatus for positioning the upper surface of the square tube in parallel with the moving direction of the welding torch when performing, the base, and provided at a required distance on the base and supporting both ends of the square tube as support shafts A supporting device rotatably supported by:
When required for at least one support shaft of the support device 9
A rotation drive device for applying a rotation drive force of 0 degree, and a rotation drive device interposed between the support shaft and the rotation drive device, the drive connection to the support shaft is released when necessary, and the support shaft can be freely rotated. And a reference portion parallel to the moving direction of the welding torch, and the base can be moved back and forth in the direction orthogonal to the axis of the square tube from the base, and the upper surface or the lower surface of the square tube surface is referred to when necessary. And a pressing device for pressing the square tube surface at the reference portion to position the upper surface of the square tube.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a front view showing an embodiment of the positioning device of the present invention, and FIG. 2 is a sectional view taken along line AA of FIG.
FIG. 3 is a sectional view taken along line B of FIG. 1; FIG. 3 is a sectional view taken along line 3-3 in FIG. 1 showing steps of welding a member to a square tube according to an embodiment of the positioning method and the positioning device of the present invention; It is a perspective view showing an example of a member and a square tube welded by a positioning method and a positioning device of the present invention.

A positioning device according to an embodiment of the present invention shown in FIG. 1 includes a base 10, a support device 20, a rotary drive device 30, a clutch device 40, and a pressing device 50. Then, the welding torch T of the robot welding machine is moved in a predetermined direction (usually horizontal direction) on the upper surface side of the square tube 15 which is placed horizontally above the base 10 and has one side surface facing upward. The required member 16 is welded on the upper surface side of the square tube 15. Thereafter, when the square tube 15 is rotated by 90 degrees about its axis center to perform welding with the member 16 on a new upper surface side of the square tube, the upper surface of the square tube 15 facing the welding torch T of the robot welding machine. The (welding surface) is accurately positioned in parallel along the moving direction of the welding torch T.

In the present embodiment, as the member 16 to be welded to the square tube 15, a connection member joined to both ends of the square tube 15 is used, and the member 16 is previously separated by another member as shown by a chain line in FIG. It is temporarily welded to both ends of the square tube 15 at the place. In addition, the method and apparatus of the present invention are not limited to the member 16 to be welded to the square tube 15 being a connection member, and can be used for welding other members. As shown in FIG.
5 is also suitable for welding to the side surface.

The base 10 is provided with a square tube 15 for welding.
Is long enough to allow
The support devices 20A and 20B are provided at positions outside the both ends of the support 5. A robot welding machine having a welding torch T is disposed near the base 10, and the welding torch T moves in a predetermined direction on the upper surface of the square tube 15 laid horizontally on the base 10 to perform welding. It is supposed to.

The support devices 20A and 20B are provided with support shafts 21A and 21B whose axes are aligned. The two support shafts 21A and 21B connect the square tube 15 to the square tube 15
For rotatably supporting the center of the shaft. As shown in FIG. 1, one support shaft 21 </ b> A is inserted into a hole 16 a provided on the end face of the member 16 to be welded in accordance with the axial position of the square tube 15. The support shaft 21 </ b> A has a conical shape whose tip fits into a hole 16 a in the end face of the member 16. The support shaft 21 </ b> A can advance and retreat in the axial direction (longitudinal direction) of the square tube 15 by an appropriate air cylinder 22. Hole 16a
Insertion and withdrawal of the support shaft 21A from the
Is pressed against the other end along the axial direction. As shown in FIG. 3, a rotary plate 23 having upright support pins 24, 24 having a conical tip is attached to the other support shaft 21 </ b> B. This support pin 2
As shown in FIG. 1, the members 4 and 24 not only support the square tube 15 to which the member 16 is temporarily welded, but also rotate the square tube 15 by the operation of the rotary drive device 30 connected to the support shaft 21B. In order to be able to do so, two are provided at point symmetrical positions about the axis of the support shaft 21B. Reference numerals 16b and 16b in FIG. 3A denote holes provided on the end face of the member 16 corresponding to the positions of the support pins 24 and 24, respectively. At least one of the support shafts 21A and 21B (in this example, 2
1B), the rotation driving device 3 via the clutch device 40
0 is connected.

The rotation driving device 30 is for applying a rotation driving force to the support shaft 21B at a required time of 90 degrees at a time, and is combined with an appropriate motor and a speed reducer. After the welding work on the surface 18 is completed,
After being rotated by 0 degrees, as shown in FIG. 3 (B), the adjacent welding surface 19 is arranged at a predetermined welding work position with the welding surface 19 facing upward.

The clutch device 40 is provided with the rotary driving device 3.
0 and the support shaft 21B are disconnected when necessary.
1B is free to rotate, thereby enabling the square tube 15 to freely rotate about its axis. As the clutch device 40, a known electromagnetic clutch or the like can be used, and can be operated by an appropriate switch.

As shown in FIGS. 1 and 2 (A), the pressing device 50 is adapted to connect the upper surface 18 serving as the welding surface of the square tube 15 supported by the support device 20 (20A, 20B) to a welding torch T. This is for fine adjustment so as to be parallel to the moving surface of the rectangular tube, and is provided above the base 10 with a reference portion 51 for pressing the upper surface 18 of the square tube 15. This reference part 51
Is arranged parallel to the moving surface of the welding torch T, and is raised and lowered toward the upper surface 18 of the square tube 15 on the base 10 by a suitable driving device 52 such as an air cylinder. It is preferable that the pressing center of the reference portion 51 be located at a position crossing the axis of the square tube 15. In the present embodiment, the reference portion 51 has a flat plate shape.
A rod member or the like disposed in a direction perpendicular to the axis direction (longitudinal direction) of the fifth embodiment may be used. The pressing device 50 presses the upper surface 18 of the square tube 15 by the reference portion 51 when the connection between the rotation drive device 30 and the support shaft 21B is released by the clutch device 40. At this time, the support shafts 21A, 21B
Is rotatable freely around the axis, so that when the upper surface 18 is not parallel to the moving surface of the welding torch T, it rotates following the reference portion 51, The square tube upper surface 18 moves to the correct position with respect to the welding torch T.

In this embodiment, the base 10 is provided with a device 60 for placing and lifting the square tube 15. The mounting and lifting device 60 is for efficiently mounting the square tube 15 on the support shafts 21A and 21B, and as shown in FIGS. 2A and 2B, the positioning stopper 63.
And is formed so as to be able to ascend and descend from the lower surface side with respect to the square tube 15 by a driving device 62 such as an air cylinder. The mounting part 61 connects the square tube 15 to the support shaft 21.
This is for temporarily placing the square tube 15 at the time of attachment to the A and 21B, and a positioning stopper 63 is provided on one side along the axial direction (longitudinal direction) of the square tube 15.

The positioning stopper 63 is used to easily and surely position the square tube on the support shaft and to prevent the square tube from being inadvertently dropped when mounted.
When the back surface of the square tube 15 in FIG. 1 is mounted on the mounting portion 61 so as to contact the positioning stopper 63, the axis of the square tube 15 is substantially the same as the axis of the support shafts 21A and 21B. It is provided at a position on the surface.

According to the placing / lifting device 60, the placing section 6
The square tube 15 is placed on the top 1 and the driving device 62 is operated to make the axis of the square tube 15 coincide with the axis of the support shafts 21A and 21B. After operating the driving device 62, one of the support shafts 21 </ b> A is
Is advanced, the tip of the support shaft 21A is quickly inserted into the hole 16a of the one member 16, and the square tube 15 is slid by pushing it toward the other support shaft 21B as it is so that the hole 16b of the other member 16 is slid. , 16b on the other support shaft 2
Since the support pins 24 of 1B are inserted, attachment to the device is easy, and subsequent welding work can be performed efficiently. The placing / lifting device 60 includes a base 10 and a square tube 1.
An appropriate number may be provided at an appropriate position in accordance with the length of 5, for example, and two in this embodiment. One of them is provided immediately below the pressing device 50.

Next, a description will be given of a method of welding work using the apparatus having such a configuration. For convenience, when the center of gravity of the square tube is on the axis, that is, as shown in FIG. The case where there is no accessory will be described. First, as shown in FIGS. 1 and 2, the square tube 15 is placed horizontally on the placement portion 61 lowered to a low position, with the upper surface 18 serving as the first welding surface facing upward, The back surface of the square tube 15 is brought into contact with the positioning stopper 63. As described above, members 16 each formed of a connection member are temporarily welded to both ends of the square tube 15 in advance. A hole 16a is formed in the end surface of the one member 16 and holes 16b and 16 are formed in the end surface of the other member 16.
b is formed.

Next, the mounting portion 61 is raised by the operation of the driving device 62 to raise the axis of the square tube 15 and the support shafts 21A, 21A.
Align with the axis of 1B. And the air cylinder 22
By moving the support shaft 21A forward in the direction of the port member 16, the tip of the support shaft 21A is inserted into the hole 16a of the port member 16. Also, the other support shaft 21B
Is disconnected from the rotation drive device 30 to allow free rotation, and the rotating plate 23 is rotated by hand or the like to match the positions of the holes 16b, 16b of the member 16 with the support pins 24, 24. . And further, the air cylinder 2
2, the member 16 is pushed to move the square tube 15 to the other support shaft 21.
When it is advanced to the side B, the support pins 24, 24 are inserted into the holes 16b, 16b, and the square tube 15 is
A, 21B securely holds. Then, the reference portion 51 of the pressing device 50 is lowered to press the upper surface 18 of the square tube 15. After that, the welding torch T of the robot welding machine is moved on the upper surface of the square tube 15 to move the member 16 to the upper surface 1 of the square tube 15.
Weld on the 8 side. At this time, since the upper surface 18 of the square tube 15 is parallel to the moving surface of the welding torch T as described above,
Appropriate welding can be performed. At the time of this welding, the mounting portion 61 may be lowered below the square tube 15.

Next, when the mounting portion 61 is not lowered, the mounting portion 61 is lowered and the support shaft 2 is moved by the clutch device 40 as shown in FIG.
1B and the rotation drive device 30 are connected. Then, the support shaft 21B is rotated 90 degrees by the operation of the rotation drive device 30, and the surface serving as the second welding surface is turned upward to form a new upper surface 19. Subsequently, by the clutch device 40,
The connection between the rotation drive device 30 and the support shaft 21B is released. Then, as shown in FIG. 3B, the reference portion 51 of the pressing device 50 provided above the base 10 is lowered,
The upper surface 19 of the square tube 15 is pressed. The support shaft 21
A and 21B are freely rotatable when the connection with the rotary drive device 30 is released, and the reference portion 51 is formed parallel to the moving surface of the welding torch T. Therefore, in a 90-degree rotation around the axis of the square tube 15, the upper surface 19 of the square tube 15
3 is not parallel to the moving plane of FIG.
As shown in (C), the upper surface 19 of the square tube 15 is pushed by the reference portion 51, and the square tube 15 rotates until the upper surface 19 of the square tube 15 correctly abuts on the reference portion 51, so that the positioning is performed correctly. Therefore, as described above, due to the variation in the angle between the adjacent surfaces of the square tube 15, the square tube 15 is rotated by 90 degrees,
Even when the upper surface of the square tube 15 is not parallel to the moving surface of the welding torch T, the positioning of the welding upper surface of the square tube 15 can be easily and accurately adjusted to be parallel to the moving surface of the welding torch T. it can.

Thereafter, as shown in FIG. 3D, while the welding torch T is moved in a predetermined direction on the upper surface 19 of the square tube 15, welding with the component 16 on the upper surface 19 of the square tube 15 is automatically performed. Do. Thereafter, according to the number of required welding surfaces of the square tube 15, the above-mentioned operation, that is, the procedure of FIGS. 3A to 3D is repeated, and the square tube 15 is sequentially rotated by 90 degrees, and a new upward direction is performed. The upper surface of the square tube 15 is positioned and welded by the pressing device 50, and the member 16 is welded to the square tube 15. After the welding is completed, the support shaft 2 is supported by the air cylinder 22 while the square tube 15 is supported from below by the placing and lifting device 60.
1A is retracted, the support shaft 21A and the support pin 24 are removed from the member 16, and the square tube 15 is removed from the positioning device 10 using a lift or the like.

In another embodiment, the pressing device 50 above the square tube 15 may not be necessary so that the placing / lifting device 60 and the pressing device 50 are also used. Since the square tube 15 has the same length on the opposite sides, the square tube 15
Even if the angles of the four corners are not right angles, the square tube 15
Has a parallelogram, and the opposing surfaces are parallel. Therefore, the upper surface 18 of the square tube 15 is parallel to the lower surface, and is parallel to the moving surface T of the welding torch T. Therefore, by setting the mounting portion 61 in advance to be parallel to the moving surface of the welding torch T, the mounting portion 61 also functions as a reference portion, and the lower surface of the square tube 15 in contact with the mounting portion 61 is a welding torch. It becomes parallel to the moving plane of T.

The timing for releasing the drive connection to the support shaft by the clutch device may be either before or after the pressing device presses the square tube surface. That is, in the above-described embodiment, the disconnection of the clutch device was performed before the pressing of the rectangular tube by the pressing device. This is the desired operation. However, for example, when a required accessory is attached to a part of the side surface of the square tube and the rotational center of gravity of the square tube is eccentric, if the clutch is released before the pressing device presses the square tube surface, the square tube May be in a free rotation state, and it may be difficult to position a necessary welding surface on the upper surface. In such a case, the clutch is released after the pressing device presses the square tube. This timing setting can be easily dealt with according to the type of the square tube to be machined, not only manually but also automatically, in case of factory mass production machining. It is desirable that the pressing device is a mechanism having elasticity such as an air cylinder or a spring mechanism, and that the setting position of the reference portion has a slight pressing margin. Then, for example, when pressing the square tube while the clutch is connected, even if a slight rotation angle deviation occurs in the square tube due to rotation as described above, by releasing the clutch in the pressed state, The displacement of the rotation angle of the square tube can be corrected by the holding allowance.

[0025]

As shown and described above, according to the method for positioning a welding surface of a square tube according to the present invention, even if the angle between the outer surfaces of the square tube is not exactly a right angle, the end portion or side surface of the square tube can be obtained. When automatically welding a connection member or the like with a robot welding machine, the side surface to be the welding surface of the square pipe can always be kept parallel to the moving surface of the welding torch. Therefore, the square tube and the member can be appropriately welded, and the strength is improved, and the quality of a building unit or the like using the square tube can be improved. Further, according to the positioning device for a square pipe welding surface of the present invention, both ends of the square tube are held by the freely rotatable support shaft, and the upper or lower surface of the square tube is set parallel to the moving surface of the welding torch. Thus, a positioning device with good workability can be obtained with a simple configuration, for example, it is possible to perform proper positioning only by pressing and to easily attach and detach the square tube to and from the positioning device.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a positioning device of the present invention.

FIG. 2 is a side view of the AA cross section and the BB cross section of FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 in FIG. 1 showing stepwise welding of a member to a square tube according to an embodiment of the positioning method and the positioning device of the present invention.

FIG. 4 is a perspective view showing an example of a member and a square tube welded by the positioning method and the positioning device of the present invention.

[Explanation of symbols]

 Reference Signs List 10 base 15 square tube 16 member 20 support device 21A, 21B support shaft 24 support pin 30 rotation drive device 40 clutch device 50 pressing device 51 reference portion 60 mounting and lifting device (pressing device) 61 mounting portion (reference portion)

Claims (4)

[Claims] 1. A rectangular tube is supported laterally to perform welding with a member while moving a welding torch of a robot welding machine in a predetermined direction on the upper surface side of the rectangular tube, and then the square tube is centered on its axis. After rotating and positioning by 90 degrees, the welding torch is moved in a predetermined direction on a new upper surface to perform welding with the member,
Further, when the member is automatically welded to the square tube by repeating the rotation and welding of the square tube as necessary, the laterally mounted square tube is rotatably supported at both ends thereof, and at least one of the support shafts is provided with a clutch device. After the square tube is rotated by 90 degrees about its axis by the rotary drive, the drive connection to the support shaft by the clutch device is released when necessary and the welding torch is connected. By pressing the upper surface or the lower surface of the square tube surface with a pressing device having a reference portion parallel to the moving direction, the rotation posture is finely adjusted and positioned so that the pressing surface is parallel to the reference portion. Method for positioning the welded surface of a square tube when welding a member to a square tube to be welded. 2. The method according to claim 1, wherein the horizontal tube is rotated by 90 degrees around its axis by 90 degrees and the welding to the member is performed while the welding torch of the robot welding machine is moved in a predetermined direction on the upper surface of the square tube. An apparatus for positioning an upper surface of a square tube in parallel with a movement direction of a welding torch, comprising: a base; a base provided at a required distance from the base; and both ends of the square tube rotatable by a support shaft. A supporting device to be supported;
A rotation driving device that applies a rotation driving force of 0 degrees each; and a rotation connection device that is interposed between the support shaft and the rotation drive device, releases a drive connection to the support shaft when necessary, and enables free rotation of the support shaft. And a reference portion parallel to the direction of movement of the welding torch, and the base can be moved back and forth in the direction orthogonal to the axis of the square tube from the base, and the upper surface or the lower surface of the square tube surface is referred to when necessary. A positioning device for welding a member to the square tube, wherein the positioning device positions the upper surface of the square tube by pressing the square tube surface at the reference portion. 3. The method according to claim 1, wherein the welding position of the upper surface of the square tube is a joint between the end of the square tube and the member. 4. The method according to claim 1, wherein the welding position of the upper surface of the square tube is a joining portion between a wall surface of the square tube and a member.