JPH06285636A - Automatic welding control method for steel-frame joint - Google Patents

Abstract

PURPOSE:To drastically reduce frequency of generation of weld defects by operating a welding robot based on a second job and welding a second steel- frame joint. CONSTITUTION:A first job which changes first data taught based on second data inputted and allows the welding robot 10 to execute specified measuring operation on the actual position, shape and dimensions of the second steel-frame joint 30 is prepared. The position, shape and dimensions of the second steel- frame joint 30 to be welded actually are measured by using the welding robot 10 based on the first job. Based on the measured result, the second job to allow the welding robot 10 to weld the second steel-frame joint 30 is prepared. Based on the second job, the welding robot 10 is operated and the second steel-frame joint 30 is welded. Consequently, the welding quality can be stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic welding control method for a building steel joint used when welding is performed by an automatic welding robot for a steel joint used in a steel structure.

[0002]

2. Description of the Related Art Early welding robots for welding steel frames for buildings used in buildings and the like were basically of a teaching playback system, and the workpieces such as steel joints were completely the same. Except for the case of shape, in order to let the welding robot weld a steel frame joint with a shape different from that before, as a general rule, a human manually teaches the welding robot the start and end points and the movement between them. , So-called teaching work is required. However, when introducing a welding robot and teaching the operation of the welding robot by teaching at the production site, the price of the welding robot and other peripheral devices generally means that a steel frame finish produced by one type of teaching is used. If the number of mouths does not reach about 2,000, the cost will not be balanced. In addition, since teaching generally requires a considerable amount of time, the more the required number of teaching operations, the lower the work efficiency. In many cases, steel frames and the like used as building materials are generally produced in small quantities in a large variety, and thus, conventionally, teaching work had to be frequently performed at a production site. Therefore, there is a problem that the efficiency of the welding work using the welding robot is largely limited by the teaching work.

In order to solve such a problem, in recent years,
A welding robot of a type has been developed in which a manufacturer performs a teaching operation in advance for a welding operation with respect to a predetermined work including a steel frame joint and then ships. That is,
The manufacturer pre-teaches the basic shapes of multiple steel joints, or teaches a single basic shape, and the user side obtains basic numerical values regarding the dimensions of the steel joint to be welded. Only input data etc. When such input data is input, the welding robot automatically selects the required shape data from the pre-teached basic shape database, or uniformly expands the basic shape for single shape data. ·to shrink. Then, software (job) for performing the welding operation is created based on these data. Also, regarding welding conditions such as welding voltage, welding current, and weaving width, appropriate ones are selected according to the above-mentioned job.

In order to perform the actual welding work with such a welding robot, the user has only to input the necessary numerical data or the like to start the above-mentioned job, and therefore the user performs the teaching work of the welding robot. No need. Therefore, the work efficiency at the production site is improved as compared with the welding robot which requires teaching on the user side as in the past.

[0005]

However, in a welding robot of the type in which data is selected from a database of pre-teached basic shapes, the dimensions of the steel joint to be welded should be one of the prepared data. However, if the actual dimensions of the steel frame joint deviate greatly from any data, proper welding work cannot be performed. For this reason, when welding work is performed on a steel frame joint other than the specific dimensions that each welding robot is good at, welding defects frequently occur due to poor matching between the job and the steel frame joint. There is. Also, with welding robots of the type that expands and contracts the basic shape, the basic shape cannot be enlarged or reduced when creating a job, and the positional deviation when fixing the steel joint to the positioner. Is caused,
The created job and the actual steel joint may not match well. Even in such a case, welding defects frequently occur.

The present invention has been made based on the above circumstances, and it is not necessary for the user to perform teaching work, and an operation job that is well matched to the actual steel joint to be welded is created. It is an object of the present invention to provide an automatic welding control method for a building steel joint that can further stabilize the welding quality.

[0007]

According to the present invention for solving the above-mentioned problems, a welding robot is controlled using a control means to automatically make a column core portion and a joint flange portion of a steel frame joint. In an automatic welding control method for a steel frame joint to be welded, the operation for moving the welding robot is taught for a first steel frame joint having a standard shape and dimensions in advance, and the first data thereof is used as the control means. Of at least one of the position, shape and size of the second steel frame joint which is stored in the storage means inside and is actually the object of welding.
Data is input to the control means, the taught first data is changed as necessary based on the input second data, and the welding robot is provided with an actual second steel frame joint. At least one of position, shape and size
A first job for performing a predetermined measurement operation for one of the two, and based on the first job, the position, shape, and size of the second steel frame joint to be actually welded using the welding robot At least one of them is measured, and a second job for causing the welding robot to weld the second steel joint is created based on the measurement result by the welding robot, and based on the second job. And operating the welding robot to weld the second steel frame joint.

The predetermined measuring operation for the second steel joint is carried out at least on the side surface of the joint flange portion, the surface of the joint flange portion, and the diaphragm groove surface of the column core portion by, for example, a contact type position detecting sensor. To detect the actual position of the steel frame joint.

The predetermined measurement operation for the second steel frame joint is performed, for example, by contacting at least one point of the groove bottom and two points on the groove surface of the joint flange with a contact position detecting sensor. The actual groove shape of the second steel frame joint is detected.

The first job and the second job are created, for example, by enlarging or reducing the standard shape and dimensions stored in the storage means for each part.

[0011]

According to the present invention, the teaching of the welding robot for the standard steel frame joint is completed by the manufacturer side before shipment, and the user side actually shapes the shape of the column core portion to be welded. By inputting the data regarding, the shape and the like of the steel joint to be actually welded are measured, and the second job is created based on the measurement result, so that an accurate second job can be created. .

When the user inputs data regarding the shape and the like, the welding robot actually measures the shape and the like of the steel frame joint by the contact-type position detecting sensor. In this measurement, the actual position of the steel joint is detected by contacting a predetermined number of positions on the side surface of the joint flange portion, the surface of the joint flange portion, and the diaphragm groove surface of the column core portion. This makes it possible to correct the positional deviation and create a more accurate second job.

Further, by further contacting at least one point of the groove bottom and two points on the groove surface of the joint flange portion to detect the actual groove shape of the second steel frame joint, the detection result is obtained. Since the second job can be created based on the above, a more accurate job can be created.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view of a welding robot for performing welding by an automatic welding control method for a steel frame joint which is an embodiment of the present invention, a steel frame joint which is an object to be welded, and other devices, and FIG. FIG. 3 is a perspective view of a steel core joint which is a welded object (work), FIG. 3 is a perspective view of a column core portion before the joint flange portion of the joint is welded, and FIG. 4 is a column core portion and a joint flange portion. It is a perspective view of a groove part when welding. Figure 5
FIG. 6 is a cross-sectional view of a groove portion when welding a column core portion and a connection flange portion.

The apparatus shown in FIG. 1 is a multi-joint welding robot 10.
In order to perform touch sensing, positioners 20a and 20b that fix the steel joint 30 and move it as necessary, a controller 2 that controls the welding robot 10, a welding power source 4 that supplies electric power for welding, and touch sensing. Search sensor unit 6 of FIG. In addition, the welding robot 10
Has an articulated arm 12 and a welding torch 14 supported by the articulated arm 12. Although not shown in FIG. 1, a device for cleaning the welding torch nozzle, a welding wire 16 after cutting the arc, are provided around the welding robot 10.
There is provided a device for slicing the same, and a device for replacing a worn torch or tip.

When the work is the steel frame joint 30 as shown in FIG. 1, the column core portion 32 is provided as shown in FIGS.
The connection flange portions 34a to 34d made of I-shaped steel or H-shaped steel are welded to the four sides of the upper and lower diaphragms 32a and 32b, respectively. Then, a groove portion is a portion where each joint flange portion is abutted against the column core portion. In FIG. 1, the welding torch 14 supports the welding wire 16 and weaves the welding wire 16. In addition to this, the system of the present embodiment includes a personal computer (not shown) connected to the welding robot and is used as a control means as described later. However, if the CPU of the controller 2 of the welding robot has sufficient capacity and an input device such as a keyboard is connected, such a CPU can also be used as the control means.

In the welding robot system shown in FIG. 1, the operation of the welding robot is taught in advance about the basic shape and size of the steel joint before being shipped by the manufacturer, and the data is stored. In the case of the present embodiment, such teaching need only be performed for the first first pass even when multi-layer welding is performed, and the personal computer automatically creates operation jobs for the second and subsequent passes. The job is a program (software) for causing the welding robot to perform a predetermined operation.

As will be described later, since the welding robot of this embodiment measures the position of the steel frame joint and the groove shape of the steel frame joint at the steel frame production site, teaching for performing these measuring operations has already been performed. Has been done. In principle, all of the above teaching work is performed by the manufacturer, and the user does not have to perform the teaching work at the production site.

On the user side, first, the operator inputs numerical data relating to the shape of the steel frame joint and the shape of the groove to be actually welded. Specifically, the number of joint flanges, the width of the diaphragm of the column core, the thickness of the diaphragm, the height of the column core, the width of the joint flange,
Numerical data such as the plate thickness of the connection flange portion, the groove angle (angle θ in FIG. 5), and the root gap (width G in FIG. 5). When the position of the joint flange portion to be welded to the column core portion is not in the center of the diaphragm, the eccentricity amount indicating how much it deviates from the center is also input. Also, the groove angle and the value of the root gap are input as reference values for measurement described later, and do not always have to be input here, but by inputting them, measurement error can be prevented. can do.

The control means enlarges or reduces data previously obtained by teaching based on the numerical data input by the operator as described above, corrects the data, and measures the position of the steel frame joint. Jobs and
Automatically create an operation job on the computer to measure the groove. In the conventional method, the enlargement / reduction when creating a job was uniform for the entire basic shape of the steel joint. However, in this embodiment, the enlargement / reduction ratio can be changed for each part. Therefore, for example, even if the shape that is taught in advance is a square, an operation job for a rectangle is created by changing the enlargement / reduction ratio for each part, and conversely, a square for a square is created based on the teaching data of a rectangle. You can create motion jobs. The job here is not an actual job for the welding robot to actually perform a welding operation, but an operation job for measurement.

When such a job is created, the control means controls and operates the welding robot based on this job, first measures the actual position of the steel frame joint 32 fixed to the positioners 20a and 20b, and measures this. The displacement of the steel frame joint is judged based on the result. The positional deviation means that the position where the steel joint is actually fixed is deviated from the original position, and if the amount of this deviation is large, accurate welding cannot be performed and many defects occur. When measuring the groove, the operator refers to the groove angle and the root gap when they are input, and detects the number of positions necessary to specify the groove angle and the root gap. To do. In addition, for the measurement of this position and the measurement of the groove shape, a wire earth method, a touch energization method using a dedicated jig,
Alternatively, a contact type position detection sensor such as a mechanical three-way touch sensor can be used. All of these methods are by energizing the steel joint and the welding wire,
When the sensor comes into contact with the steel frame joint, the coordinates of the welding robot at that position are stored, and predetermined recognition and calculation are performed by a personal computer or a computer dedicated to the welding robot.

Next, a specific method of the above measurement will be described with reference to FIGS. 4 and 5. First, regarding the measurement of the position of the steel frame joint, the point and the side surface of the joint flange portion on the joint flange portion 34a side are measured in FIG. 4 to determine the position of the joint flange portion in the y direction of FIG. Then, the points on the surface of the joint flange portion and the points on the diaphragm groove surface of the column core portion are measured to determine the positions of the joint flange portion 34a and the column core portion 32 in the x direction and the z direction. This makes it possible to find the welding line between the column core portion 32 and the connection flange portion 34a.
In this case, the column core portion 32 and the connection flange portion 34a are positioned so that the uppermost surface thereof is horizontal.
It is assumed to be fixed at 0. However, if this top surface is tilted or if it is necessary to make sure that it is horizontal, the plane is determined by measuring at least 3 points, so that more points 'or', or both measure. Further, the more the points are spaced apart from each other and the more the points are spaced apart from each other, the more accurate the measurement can be made.

Considering the bending of the connection flange portion which is originally a straight line, it is desirable to measure at the center of the straight line in terms of accuracy. However, while there is a problem that the measurement time becomes too long, if there is a bend in the middle of the straight part, when welding is being performed,
Since the correction can be performed by using the arc sensor, such measurement is not executed in this embodiment.

Next, the diaphragm 32a of the column core portion
The measurement of the groove shape will be described with reference to FIG. 5, which shows a cross section of the groove portion which is a joint portion between the joint and the flange portion 34a. The sensor measures one point on the groove surface of the diaphragm, one point on the surface of the backing 38 that is the groove bottom, two points above and below the groove surface of the finish flange 34a, and ′. However, one point on the groove surface of the diaphragm is shown in FIG.
It is also possible to use data such as points obtained by the positional deviation measurement described in the above. The groove angle θ is measured by measuring two points on the groove surface of the joint flange and
Can be calculated. Note that, again, it is assumed that the column core portion 32 and the joint flange portion of the joint flange portion 34a are horizontally fixed. The same measurement operation as above is performed for the remaining connection flange portions 34b-34.
Repeat for d.

As described above, the diaphragm 32a has four
Regarding the sides, the column core portion 32 and the connection flange portion 34a to
When the displacement of the steel frame joint and the measurement of the groove shape are performed for 34d, an operation job for actually causing the welding robot to weld the groove portion is created based on these measurement results. For this operation job, welding conditions are automatically selected and set in addition to the movement trajectory of the welding robot. These welding conditions include welding current, welding voltage, welding speed (mm / sec),
The presence or absence of weaving is included. The welding method used in this example is a carbon dioxide gas shielded arc welding method. This final operation job creation work is also automatically performed by the personal computer.

In this embodiment, even when multi-layer welding is performed, the data initially given by the teaching on the manufacturer side is only for one pass. Therefore, from the measured data such as the groove angle, the root gap, and the plate thickness, the movement locus of the welding torch in the case of performing the welding in the second and subsequent passes is also automatically obtained. However, if it is not multi-layer welding, such work is naturally unnecessary.

In the case of creating the final motion job described above, the so-called taper gap correspondence method is used. That is, the straight line of the joint between the diaphragm 32a of the column core portion 32 and the joint flange portion of the joint flange portion 34a is evenly divided into, for example, eight portions, and each divided portion has a groove-shaped cross section or Welding conditions are regarded as the same. The larger the number of divisions, the higher the welding accuracy. By using such a method, even if the groove shape varies linearly from one end to the other end of the straight portion, for example, welding the respective parts under optimum conditions You can In order to be able to apply this taper gap correspondence method, the condition is that the joint part is almost a perfect straight line, and it cannot be applied, for example, when the groove shape in the middle has a mountain-shaped variation.
However, because the groove of the building steel frame is generally produced with high precision by machining, and because a certain root gap is provided and the backing 38 is applied, it is considered that there is no large variation in the straight line of the joint. be able to. Therefore, in the general case, the taper gap correspondence method is sufficiently applicable. Since the final job created in this way is based on the actual measurement results, the matching with the steel frame joint to be actually welded is extremely good.

When the final job is created in this way,
This job can be started by the operator, for example, by pressing a predetermined button, which causes the welding robot to attach the connection flange portion 34 to the four sides of the diaphragm 32a.
The operation of welding a to 34d is started. When actually performing multi-layer welding, tabs are provided at both ends of the groove to prevent the molten metal from flowing down. The tabs that can be used include ceramics tabs, steel tabs, flux tabs, etc., but ceramic tabs are preferable in this embodiment. Also, when welding the end where the tab is provided,
In this embodiment, the welding robot is devised to incline the torch so that the tab can be welded to the end without contacting the torch nozzle.

Next, this time, the connection is reversed to the back side, and the diaphragm 32b of the column core and each connection flange 34a.
On the back side of ~ 34d, the same measurement operation and welding work as those performed above are performed, whereby the welding of one steel frame joint is completed. Since such welding work is based on the job created based on the actual measurement results as described above, the operation is extremely suitable for the steel frame joint to be welded, and the quality of the obtained welding is Very stable.

In the case of a steel frame joint, since welding work must be performed on both of the two diaphragms of the column core portion as described above, it is necessary to invert the whole joint halfway to the back side. . In this example, one side was first measured, a job was created, and welding was performed, and then the same operation was performed on the other side. If the measurement work is completed on both sides and then the welding work is started, it is disadvantageous that the reversing work must be performed once during the measurement, once during the welding, and twice in total. In particular, since it is necessary to retract the welding robot when reversing the steel joint, it is possible to perform measurement to welding on one side first, and then perform measurement and welding on the other side as in the present embodiment. desirable.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention. For example, in the above-described embodiment, the case where the groove shape is a L-shape has been described, but the groove shape may be an I-shape or a V-shape. Further, the measurement of the position and groove shape of the steel frame joint is not limited to the above items 1 to 3. Further, in the above embodiment, the shape of the steel frame joint was input by the operator, but this shape may be measured by the contact type position detection sensor and the input value may be corrected. .

[0032]

As described above, according to the first aspect of the invention, the teaching work is performed only at the stage of manufacturing the welding robot and its peripheral devices.
At the steel frame production site, you only need to enter the necessary numerical data about the steel joint, then the control means creates the job that requires the measurement of the shape of the steel joint, etc. Since a job for welding work is created, work efficiency is significantly improved compared to the conventional method that required teaching work at the production site.
At the production site, the welding robot actually measures the shape of the steel joint, etc., and creates the final operation job based on this, so this operation job will match well with the actual shape of the steel joint, Therefore, it is possible to provide an automatic welding control method for a steel frame joint in which the frequency of occurrence of welding defects is significantly reduced by performing welding work based on such a job, and the welding quality is stabilized.

According to the second aspect of the present invention, the contact-type position detection sensor is used to provide at least a predetermined number of positions on the side surface of the joint flange portion, the surface of the joint flange portion, and the diaphragm groove surface of the column core portion. The position of the steel joint to be actually welded can be detected by detecting the actual position of the steel joint by contacting with the contact, thereby compensating the positional deviation and creating a more accurate second job. You can
Therefore, it is possible to provide an automatic welding control method for a steel frame joint in which the frequency of occurrence of welding defects is significantly reduced and the welding quality is stabilized.

Further, according to the invention of claim 3, the actual groove of the second steel frame joint is further in contact with at least one point of the groove bottom and two points on the groove surface of the joint flange portion. By detecting the shape and creating the second job based on this detection result, a more accurate job can be created, and therefore the frequency of occurrence of welding defects is further greatly reduced and the welding quality is stabilized. It is possible to provide an automatic welding control method for a steel joint.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a welding robot that operates by an automatic welding control method for a steel frame joint according to an embodiment of the present invention and a steel frame joint that is an object to be welded.

FIG. 2 is a perspective view showing a steel frame joint to be welded.

FIG. 3 is a perspective view of a column core portion.

FIG. 4 is a perspective view of a groove portion before welding between a diaphragm of a column core portion and a connection flange portion.

FIG. 5 is a cross-sectional view of a groove portion before welding between a diaphragm of a column core portion and a connection flange portion.

[Explanation of symbols]

 10 Welding robot 12 Multi-joint arm 14 Welding torch 16 Welding wire 20a, 20b Positioner 30 Steel frame joint 32 Column core part 32a, 32b Diaphragm 34a-34d Joint flange part 38 Backing

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000233701 Nippon Steel Welding Industry Co., Ltd. 3-5-4 Tsukiji, Chuo-ku, Tokyo (72) Inventor Iwa Shimizu 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel shares Company Technology Development Headquarters (72) Inventor Shunsuke Fukami 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Co., Ltd. Corporate Technology Development Headquarters (72) Hiroshi Tachikawa 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Co., Ltd. Corporate Technology Development Division (72) Inventor Yamashita ▲ Ore ▼ 3 Shintomi 20-1 Shintomi Futtsu City, Chiba Prefecture Nippon Steel Corporation Corporate Development Division (72) Inventor Toru Noda 7-6-1 Higashi Narashino, Narashino City, Chiba Prefecture Nittetsu Welding Industry Co., Ltd. Equipment Division (72) Inventor Shinji Okumura 2-1, Kurosaki Shiroishi, Hachimansai-ku, Kitakyushu City Yasukawa Electric Robot Factory (72) Inventor Kazuhiko Tata 2-1, Kurosaki Shiroishi, Yawatanishi-ku, Kitakyushu City Incorporated Yaskawa Electric Robot Factory (72) Inventor Masao Tamada 2-1, Kurosaki Shiroishi, Yawatanishi-ku, Kitakyushu City Incorporated Yaskawa Electric Robot Factory (72) Inventor Takeyoshi Kanehara 2-1, Kurosaki Shiroishi, Hachimansai-ku, Kitakyushu City, Ltd. Yaskawa Electric Robot Factory Co., Ltd. (72) Inventor Kiyoshi Kawami 2-19-7 Akanehama, Narashino City, Chiba Prefecture Yaskawa Corporation Robot Engineering Department

Claims (4)

[Claims] 1. An automatic welding control method for a steel joint, which controls a welding robot using a control means to automatically weld a column core portion and a joint flange portion of a steel joint to a standard welding method. Teaching the operation for moving the welding robot with respect to the first steel frame joint having the shape and size, and storing the first data in the storage means in the control means, which is actually the object of welding. The second data relating to at least one of the position, shape and size of the second steel joint is input to the control means, and the taught first data is based on the input second data. And changing as necessary to create a first job for causing the welding robot to perform a predetermined measurement operation for at least one of the actual position, shape, and size of the second steel joint, The above At least one of the position, shape, and size of the second steel frame joint to be actually welded using the welding robot is measured based on one job, and based on the measurement result by the welding robot, Second for welding robot to weld second steel joint
The method of: (1) creating a job of (1), operating the welding robot based on the second job, and welding the second steel frame joint, the automatic welding control method of the steel frame joint. 2. The predetermined measuring operation for the second steel frame joint is carried out at least on the side surface of the joint flange portion, the surface of the joint flange portion, and the diaphragm groove surface of the column core portion by the contact type position detecting sensor. The automatic welding control method for a steel frame joint according to claim 1, wherein the actual position of the steel frame joint is detected by contacting a predetermined number of positions. 3. The predetermined measurement operation for the second steel frame joint is performed by contacting at least one point on the groove bottom and two points on the groove surface of the joint flange with a contact position sensor. 3. The automatic welding control method for a steel frame joint according to claim 2, wherein the actual groove shape of the second steel frame joint is detected. 4. The first job and the second job are created by enlarging or reducing a standard shape and size stored in the storage unit for each part. Item 4. The automatic welding control method for a steel joint according to item 1, 2 or 3.