JPH05215510A - Welding position detecting method - Google Patents

Abstract

PURPOSE:To make it possible to detect the position of a weld line by providing a position detecting means, and detecting the planar positions (shoulder heights) of prism-shaped members at both sides of the weld line. CONSTITUTION:Distances between a position sensor 2 and the surfaces of prisms 1A and 1B are obtained based on the received light data obtained with a light receiving part 2b, and the detected data (the height position data of the surfaces of the prisms 1A and 1B) are obtained. The surface positions of the prisms 1A and 1B along detecting lines 5 are also scanned and detected with a driving mechanism and the sensor 2. Furthermore, a shoulder-height operating part 4a computes the height positions (shoulder heights) of planar parts 1b of the prisms 1A and 1B, which are arranged horizontally, by averaging the height- position data of the planar parts 1b of the prisms 1A and 1B, which are detected with the sensor 2. A weld-line-position operating part 4b operates the position of the weld line 6 between the prisms 1A and 1B based on a specified radius R of a preset known corner part 1a and the shoulder heights of the prisms 1A and 1B, which are operated with the shoulder-height operating part 4a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint portion for welding prismatic members having at least one corner portion (R portion) which is curved at a predetermined radius, and determines the position of a welding line between the prismatic members. The present invention relates to a welding position detecting method for detecting.

[0002]

2. Description of the Related Art Generally, in an automatic welding machine, a welding robot or the like, in order to carry out a precise welding operation, it is necessary to recognize the shape of a work object and to accurately detect the position of a welding line. ..

Therefore, heretofore, JP-A-3-32469, JP-A-3-32470, and JP-A-3-2041 have been used.
As disclosed in Japanese Patent Laid-Open No. 78, Japanese Patent Laid-Open No. 3-207577, etc., after obtaining image data by irradiating a work target work with a laser beam or the like using an optical sensor,
The shape of the work is recognized based on the image data to detect the position of the welding line. Further, in Japanese Patent Laid-Open No. 3-221267, etc., the position of the welding line is determined by teaching in advance several points of the welding line from the start point to the end point.

[0004]

However, the conventional welding position detecting means is effective only when the surface of the work piece is constituted by a substantially straight line (generally flat face) at the joint portion, and the curve ( It could not be applied to the detection of the weld line position for the welded joint of a workpiece configured with a curved surface.

For example, when building a housing unit,
It is necessary to make a frame by welding steel columnar members such as beams and columns, and when connecting units of such a frame to build a unit house,
We need to weld columns or beams to each other,
Usually, the corner portion of such a prismatic member is often curved with a predetermined radius, and in order to automate the welding operation, the surface shape of the prism having the R portion is recognized and the welding line position is accurately determined. It is desired to be able to detect.

The present invention is intended to solve such a problem, and makes it possible to accurately detect the welding line position of a welded joint made of a prism having an R portion, and to perform the welding operation for the prism having the R portion. It is an object of the present invention to provide a welding position detecting method capable of realizing automation.

[0007]

In order to achieve the above object, a welding position detecting method of the first invention (claim 1) is to weld adjacent prismatic members to each other. A method for detecting the position of a welding line between the prismatic members when at least one has a corner portion curved at a predetermined radius, wherein the surface position of the adjacent prismatic members is the welding line. With a position detecting means for detecting along a direction orthogonal to, by the position detecting means, respectively detects the planar position of each of the prismatic members on both sides of the welding line, a predetermined radius of the corner portion, The position of the welding line is detected based on the planar position of each prismatic member detected by the position detecting means.

According to the welding position detecting method of the second invention (claim 2), at the time of welding the adjacent prismatic members, at least one of the adjacent prismatic members has a corner portion curved at a predetermined radius. In the case of a method for detecting the position of the welding line between the prismatic members, the position detecting means for detecting the surface position of the adjacent prismatic members, the position detecting means, The positions of two points, that is, the starting point side position and the ending point side position of the welding line are detected, and at each of the starting point side position and the ending point side position, the position detecting means determines the surface position of the adjacent prismatic member. By detecting along the direction orthogonal to the welding line to detect the plane positions of the prismatic members on both sides of the welding line, the predetermined radius of the corner portion and the position detecting means are used. The position of the welding line is detected based on the detected planar position of each of the prismatic members, the start point side position and the end point side position, and the welding at each of the start point side position and the end point side position. It is characterized in that the position of the welding line is determined over the entire length thereof based on the position of the line.

Further, the position detecting means may detect the positions of at least three points on the corner, and the predetermined radius of the corner may be obtained based on the positions of the three points.

[0010]

The welding position detecting method of the present invention described above (Claim 1)
Then, the position detecting means detects the plane position (shoulder height) of each prismatic member on both sides of the welding line, respectively, based on the plane position and the predetermined radius of the corner portion of the prism,
The position of the welding line is detected (automatic recognition).

Further, in the method of claim 2, first, the position detecting means determines whether the position of the welding line is the starting point side or the ending point side.
Detect the position of a point. Then, at the detected respective positions of the starting point side position and the ending point side position, in the same manner as in the method of claim 1, the position detecting means causes the planar position (shoulder height) of each prismatic member on both sides of the welding line. Respectively,
The position of the welding line is detected (automatic recognition) based on the plane position and the predetermined radius of the corner of the prism. After that, the position of the welding line is detected / determined (automatically recognized) over the entire length thereof based on the position of the start point side and the position of the end point side, and the position of the welding line at each of these positions.

Further, as for the corner portion of the prism, if the positions of at least three points are known, a circle passing through the three points can be obtained, that is, a predetermined radius of the corner portion can be obtained. Therefore, it is possible to automatically recognize the predetermined radius of the corner portion of the prism by detecting the positions of at least three points on the corner portion of the prism by the position detecting means.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 6 show a welding position detecting method (corresponding to claim 1) as a first embodiment of the present invention. 4 is a block diagram showing a configuration of an apparatus to which the method is applied, FIG. 2 is a perspective view schematically showing an appearance of the apparatus, FIG. 3 is a diagram for explaining detection data by the position sensor, FIG.
Is a diagram showing an actual work cross-sectional shape in the present embodiment, FIG. 5 is a flow chart for explaining the operation of the apparatus,
6 (a) and 6 (b) are diagrams for explaining a detailed calculation procedure for detecting a welding line in the apparatus.

In FIGS. 1 and 2, 1A and 1B are prisms each having a corner portion 1a curved at a predetermined radius R.
In the present embodiment, when these prisms 1A and 1B are arranged adjacent to each other along their longitudinal direction and are welded to each other, a welding line between these prisms 1A and 1B is used. Attempt to detect position 6 Further, 1b is a plane portion of each prism 1A, 1B, and two prisms 1A, 1B are arranged adjacent to each other so that one of the plane portions 1b is horizontal.

Each of the prisms 1A and 1B is formed into a prismatic shape by applying pressure from four directions to a hollow cylinder, and has corners 1a having a predetermined radius R at its four corners. However, the predetermined radius R can be obtained if the plate thickness of the original cylinder is known, and in this embodiment, the predetermined radius R is known to be used by taking this fact into consideration, and the welding line The position shall be detected.

Reference numeral 2 is an optical system for detecting the surface position (height position) of the prisms 1A and 1B along the detection line 5 in the longitudinal direction of the prisms 1A and 1B, that is, in the direction orthogonal to the direction of the welding line 6. With the position sensor (position detecting means), the position sensor 2
Is a light emitting unit 2 that emits light (for example, laser light) and irradiates the surfaces of the prisms 1A and 1B in a spot shape as shown in FIG.
a and the prisms 1A, 1 after being irradiated from the light emitting portion 2a
Light receiving unit 2 for receiving the reflected light reflected on the surface of B
and b.

Then, the distance between the position sensor 2 and the surfaces of the prisms 1A and 1B is obtained based on the received light data obtained by the light receiving portion 2b, for example, the optical path difference data, the reflected light intensity, etc., as shown in FIG. Various detection data (height position data of the surfaces of the prisms 1A and 1B) can be obtained.

Here, in the present embodiment, the actual work cross-sectional shape is as shown in FIG. 4, whereas the data as shown in FIG. 3 is obtained. This is a prism 1A,
Between 1B each other, the position of more than a certain depth shown by the dotted line in FIG. 3, prism 1A, insufficient amount of light reflected from the surface of 1B, and because the position detection is impossible, and the position P ₄ to the The data between P ₇ does not make sense. If the distance (groove width) between the prisms 1A and 1B is sufficiently large, such a portion in which the position cannot be detected does not occur, and the position sensor 2 detects the same detection data as that shown in FIG. Can be obtained.

Further, 3 is a drive mechanism 3 for driving the position sensor 2. With this drive mechanism 3, the surface position of the prisms 1A and 1B along the detection line 5 as shown in FIG. It is designed to be scanned and detected.
The drive mechanism 3 may drive the position sensor 2 itself as a whole, or may change the irradiation direction of the light from the light emitting section 2a using a mirror or the like inside the position sensor 2. May be.

On the other hand, 4 is a computer which is connected to the position sensor 2 and performs a calculation based on the data detected by the position sensor 2 to recognize the surface shape of the prisms 1A and 1B, and the shoulder height calculation unit 4a and the welding line. The position calculator 4b is included.

The shoulder height calculation unit 4a averages the height position data of the plane portions 1b of the prisms 1A and 1B detected by the position sensor 2, thereby arranging the prisms 1 arranged horizontally.
The height position (shoulder height) of the flat surface portion 1b of A and 1B is calculated, and the welding line position calculation portion 4b, as will be described in detail with reference to FIGS. Corner 1
Based on the predetermined radius R of a and the shoulder height of each prism 1A, 1B calculated by the shoulder height calculator 4a, the prisms 1A, 1B.
The position of the welding line 6 between them is calculated.

Next, the welding line 6 between the prisms 1A and 1B is calculated by the apparatus of the present embodiment configured as described above.
The detection process will be described with reference to FIGS. 3, 5 and 6. First, in this embodiment, in order to weld the prisms 1A and 1B, the planar portions 1b of the prisms 1A and 1B are horizontally arranged adjacent to each other, and the position sensor 2 disposed vertically to the planar portion 1b is used. , Detection line 5 (direction orthogonal to welding line 6)
By detecting the surface positions (height positions) of the prisms 1A and 1B along the line, detection data as shown in FIG. 3 is obtained. Here, as shown in FIG. 3, positions P _{3 to} P ₅ and positions P ₆ to
The section P ₈ is the R portion, that is, the corner portion 1a, and the other portion is the substantially straight portion, that is, the flat portion 1b.

The flat portion 1b of each prism 1A, 1B
By averaging the position data between the positions P _{1 and} P ₂ and the position data between the positions P _{9 and} P _10, which are (straight line portions), by the shoulder height calculation unit 4a, the average value becomes horizontal. It is calculated as the height position (shoulder height) of the flat surface 1b of each of the arranged prisms 1A and 1B (step A1 in FIG. 5).

After that, in the welding line position calculation unit 4b,
As shown in FIG. 6 (a), a prism 1 having a height reduced by a predetermined height h, h ′ from each shoulder height obtained as described above.
A, the position on the surface of the 1B, respectively determine the P _4, P ₇ as shown in Figure 6 (step A2 in FIG. 5), as shown in FIG. 6 (b), position vertically below the position P ₇ The same height position P as P ₄
'After asking (step of FIG. 5 A3), these positions P ₄ and P _{7' 7} Request horizontal distance D (step A in FIG. 5
4).

Here, in this embodiment, as described above,
The predetermined radius R of the corner portion 1a of the prisms 1A and 1B is known.
Since the welding line position calculation unit 4b is set in advance,
As shown in (b), from the predetermined radius R to the position P₃And P_FourWith water
By subtracting the flat distance c, the position P_FourAnd P_FiveHorizontal with
The distance d is calculated, and the position P from the predetermined radius R is calculated. ₇
And P₈By subtracting the horizontal distance c ′ from₆
And P₇The horizontal distance d'from 'is calculated (step in FIG. 5).
A5). In addition, the horizontal distance d obtained in step A5,
From d ', the gap (groove width) between the prisms 1A and 1B x
Is calculated as x = D- (d + d ') (Fig.
5 step A6).

6 (a) and 6 (b) show the case where the positions of the plane portions 1b of the right and left prisms 1A and 1B are different, that is, a step is formed. Further, here, the predetermined radius R of the corner portion 1a of each prism 1A, 1B is the same, but the predetermined radius is the prism 1A, 1B.
It may be different for each. Further, in the present embodiment, the horizontal distances d and d ′ are calculated from the predetermined radius R to the horizontal distance c,
The horizontal distances d and d ′ are calculated by subtracting c ′.
It can also be geometrically determined from h and h'and a predetermined radius R, respectively.

Based on the calculated values obtained as described above, the shoulder height of each prism 1A, 1B, the gap size x and its position (groove shape) are obtained, and welding is performed using these values. The position of the line 6 can be accurately detected and automatically recognized. Therefore, there is an advantage that the welding work of the joint portion between the prisms 1A and 1B having the R portion can be automated.

Next, a welding position detecting method as a second embodiment of the present invention will be described with reference to FIGS. 7 to 11. FIG. 7 is a block diagram showing the construction of an apparatus to which the method is applied, and FIG. FIG. 9A and FIG. 9B are perspective views schematically showing the external appearance of the state when the starting point position (or the ending point position) of the welding line is detected by the device, and FIGS. 9A and 9B show the starting point position and the ending point of the welding line, respectively. FIG. 10 is a diagram showing data at the time of detecting the position, FIG. 10 is a schematic diagram showing the total length of the welding line detected by the apparatus, and FIG. 11 is a flow chart for explaining the operation of the apparatus. The same reference numerals as those used above indicate the same parts, and a description thereof will be omitted.

As shown in FIG. 7, the apparatus of this embodiment is also the first
The device of the second embodiment has substantially the same configuration as that of the device of the embodiment, but in the device of the second embodiment, the start point (start point side position) and the end point (start point side position) of the welding line 6 are displayed on the computer 4 based on the detection data from the position sensor 2. Start point / end point detection unit 4c for detecting the end point position)
Is provided. The other parts are constructed in exactly the same way as in the first embodiment, and therefore their explanations are omitted.

As shown in FIG. 8, the start point / end point detecting section 4c, based on a change in detection data obtained by scanning the position sensor 2 along the entire length of the prism 1B (or 1A) in the longitudinal direction, The start point and the end point of the welding line 6 (the positions of the end faces 1c and 1d of the prisms 1A and 1B in this embodiment) are detected, and when the rising edge of the detection data as shown in FIG. While the rising portion is detected as the starting point (end surface 1c) of the welding line 6, when the falling edge of the detection data as shown in FIG. 9 (b) is detected, the falling portion is detected as the ending point of the welding line 6 (end surface 1d). ) Is detected.

In the apparatus of this embodiment, the first
The welding line detection operation by the shoulder height calculation unit 4a and the welding line position calculation unit 4b described above in the embodiment is performed at each time when the start point / end point is detected by the start point / end point detection unit 4c described above. ing.

In the second embodiment of the present invention having the above-described structure, first, as shown in FIG. 8, the position sensor 2 is connected to the prism 1B.
When the rise due to the existence of the prism 1B is detected by the position sensor 2 as shown in FIG. 9 (a) by scanning from the end face 1c side along the longitudinal direction of the prism 1B, the start point / end point detection unit 4c It is determined that the starting point (end face 1c) of the welding line 6 has been detected (step B1 in FIG. 11), and the groove shape at the starting point of the welding line 6 is detected / recognized (step B2 in FIG. 11). Detection of groove shape by this step B2
The recognition is performed by the same procedure as in the first embodiment.

Next, when the position sensor 2 is further scanned along the longitudinal direction of the prism 1B, as shown in FIG. 9B, when the position sensor 2 detects a fall due to the disappearance of the prism 1B, Welding line 6 by the start point / end point detection unit 4c
It is judged that the end point (end face 1d) of the welding line 6 has been detected (step B3 in FIG. 11), and the groove shape at the end point of the welding line 6 is detected / recognized (step B4 in FIG. 11). The groove shape detection / recognition in step B4 is performed by the same procedure as in the first embodiment.

In this way, as shown in FIG. 10, the welding line 6 between the prisms 1A and 1B has four points, that is, both ends of the groove width at the starting point and both ends of the groove width at the ending point. The positions of the welding line 6 are detected and determined over their entire length by linearly approximating these points and connecting the start point side and the end point side (step B5 in FIG. 11).

As described above, according to the second embodiment of the present invention, similarly to the first embodiment, the position of the welding line 6 can be accurately detected and automatically recognized, and the prisms 1A and 1B having the R portion are connected to each other. In addition to automating the welding work of the joint part, by detecting the start point and the end point of the welding line 6 and recognizing the groove shape at each point, the position over the entire length of the welding line 6 can be accurately recognized automatically. There are also advantages.

In the above embodiment, each prism 1A, 1B is used.
It is assumed that the predetermined radius R of the corner portion 1a is known, but the distance (groove width) between the prisms 1A and 1B is sufficiently large, and the position undetectable portion as shown in FIG. 3 does not occur. In addition, the position sensor 2 detects the positions of at least three points on the corners 1a of the prisms 1A and 1B, and based on the positions of these three points, a predetermined radius R of the corners 1a of the prisms 1A and 1B. May be automatically recognized. In this case, it is not necessary to separately obtain the predetermined radius R of the corner portion 1a in advance, and the work can be further automated.

Further, the present invention is not limited to the above-mentioned embodiments, and is included in the scope of the present invention even if there are design changes and the like within a range not departing from the gist of the present invention. For example, in the above embodiment, two prisms 1 that are adjacently arranged to be welded are used.
The case where the corner portion 1a having the predetermined radius R is formed in each of A and 1B has been described, but as shown in FIG. 12, one prism 1C may have no R portion. Welding as shown in FIG.
This is a case in which a joint piece (a prismatic member having no R portion) is welded to a pillar material forming a housing unit so as to connect the beam material to the pillar material.

[0038]

As described in detail above, according to the welding position detecting method (Claim 1) of the present invention, the position detecting means detects the planar positions of the prismatic members on both sides of the welding line, respectively. Since the position of the welding line is detected based on the plane position and the predetermined radius of the corner portion of the prism, the position of the welding line of the welded joint made of the prism having the R portion can be accurately detected, and the welding operation can be performed. The effect is that automation of can be realized.

According to the method of claim 2, by detecting the starting point side position and the ending point side position of the welding line and recognizing the groove shape at each point by the same method as in claim 1. There is also an effect that the position over the entire length of the welding line can be accurately recognized automatically.

Further, by detecting the positions of at least three points on the corners of the prism by the position detecting means, the predetermined radius of the corners of the prism can be automatically recognized, and it is not necessary to separately determine the predetermined radius. There is also an effect that further automation can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an apparatus to which a welding position detecting method according to a first embodiment of the present invention is applied.

FIG. 2 is a perspective view schematically showing the external appearance of the device according to the first embodiment.

FIG. 3 is a diagram for explaining detection data by the position sensor of the first embodiment.

FIG. 4 is a diagram showing an actual workpiece cross-sectional shape in the first embodiment.

FIG. 5 is a flow chart for explaining the operation of the device of the first embodiment.

6 (a) and 6 (b) are diagrams for explaining a detailed calculation procedure for detecting a welding line in the apparatus of the first embodiment.

FIG. 7 is a block diagram showing a configuration of an apparatus to which a welding position detecting method as a second embodiment of the present invention is applied.

FIG. 8 is a perspective view schematically showing an appearance of a state in which a starting point position (or an ending point position) of a welding line is detected by the device of the second embodiment.

9 (a) and 9 (b) are diagrams showing data at the time of detecting the starting point position and the ending point position of the welding line by the position sensor of the second embodiment, respectively.

FIG. 10 is a schematic diagram showing the total welding line length detected by the device of the second embodiment.

FIG. 11 is a flow chart for explaining the operation of the apparatus of the second embodiment.

FIG. 12 is a perspective view showing a modified example of the prismatic member welded by the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1A to 1C Prismatic column (columnar member) 1a Corner part 1b Plane part 1c, 1d End face 2 Optical position sensor (position detecting means) 2a Light emitting part 2b Light receiving part 3 Driving mechanism 4 Computer 4a Shoulder height calculating part 4b Welding line position Calculation part 4c Start point / end point detection part 5 Detection line 6 Weld line

Claims (3)

[Claims] 1. When welding adjacent prismatic members, when at least one of the adjacent prismatic members has a corner portion curved at a predetermined radius,
A method for detecting the position of a welding line between the prismatic members, comprising position detecting means for detecting the surface position of the adjacent prismatic members along a direction orthogonal to the welding line, and the position detection By means of detecting the plane position of each of the prismatic members on both sides of the welding line, the predetermined radius of the corner portion and the plane position of each of the prismatic members detected by the position detecting means. A welding position detecting method, wherein the position of the welding line is detected based on the welding position. 2. When welding adjacent prismatic members, when at least one of the adjacent prismatic members has a corner portion curved at a predetermined radius,
A method of detecting the position of a welding line between the prismatic members, comprising position detecting means for detecting the surface position of the adjacent prismatic members, the position detecting means, the starting point side position of the welding line And the end point side position are detected, and at each of the start point side position and the end point side position, the position detecting means causes the surface position of the adjacent prismatic member to be orthogonal to the welding line. Along the welding line to detect the planar position of each prismatic member, and the predetermined radius of the corner and the planar position of each prismatic member detected by the position detecting means. The position of the welding line is detected based on, and the starting point side position and the ending point side position, and the position of the welding line at each of these starting point side position and ending point side position And the position of the welding line is determined over the entire length thereof. 3. The position detecting means detects the positions of at least three points on the corner, and calculates the predetermined radius of the corner based on the positions of the three points. 2. The welding position detecting method described in 2.