JPH0630814B2 - Welding position determination method and welding method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a welding position determination method and a welding method in corner joint welding of plate materials.

(Prior Art) Conventionally, in order to perform corner joint welding using an automatic welding machine, a welding torch position with respect to a welded portion is set in advance, a method of repeating operations as taught, and a position sensor are provided. However, there is a method of performing welding while correcting the welding torch position based on the data obtained therefrom.

In recent years, automatic welding machines having position sensors have become mainstream, and various methods for position detection have been devised depending on the shape of the welded part and the like.

(Problems to be Solved by the Invention) An object of the present invention is to provide a method for determining a welding position which has not been heretofore available and a simple welding method based on the method for determining a welding position.

(Means for Solving the Problem) In order to achieve the above object, the welding position determining method and welding method of the present invention are, firstly, joint welding of plate materials arranged so as to intersect each other at the ends of a pair of plate materials. , The position coordinate of the joint portion is detected by using the light cutting method, and at the same time, the equation on the image processing plane of the light cutting line image projected on the side surface of the plate is determined, and these data and the plate thickness of the plate and The welding position of the plate material is determined by calculating data such as a gap, a step, and a crossing position of the joint portion of the plate material from the data of the crossing angle of the plate material.

The second is joint welding of plate members arranged so as to intersect each other at the ends of a pair of plate members, and the position coordinates of the joint portion are detected by using the light cutting method, and at the same time, the light cutting line projected on the side surface of the plate members. Obtaining the equation of the image on the image processing plane, and calculating the data of the gap, step, intersection position, etc. of the joint portion of the plate material from these data and the data of the plate thickness of the plate material and the intersection angle of the plate material. According to the method for determining the welding position of the plate material, according to the method for determining the welding position of the plate material, each optical cutting line image is arranged at each position (plate material 1 and plate material 2) of the plate material when detecting the position coordinates. 2
The method according to claim 1, wherein a light section image of a book is used.

Thirdly, when the position coordinates are detected, the obtained light section line image is subjected to a differential process, and the position coordinates of the end image portion are obtained from the inflection point thereof. Is.

Fourth, at the time of detecting the position coordinates, an image of the edge portion of the plate is extracted from the image of the joint portion obtained by a normal light source by means of spatial filtering or the like, and the intersection point of this image and the light cutting line image is extracted. The method according to claim 1 or 2, wherein the position coordinates of the edge portion of the plate material are obtained from and.

Fifthly, in the methods 1, 2, 3 and 4, the welding current value, the filler feed amount, etc. as optimum welding conditions are determined from the obtained gap data of the joint portion of the plate material and the step data, and the intersection is determined. An object of the present invention is to provide a welding method in which welding is performed by controlling the welding torch to an optimum position based on position data.

(Operation) As described above, the light-cutting method is used to detect the light-opening shape and the positional shift of the joint portion, and (1) the equation on the image processing surface of the light-cutting line image is obtained. (2) Differentiate the light section line image. (3)
The position coordinates P and Q of the edge portion are accurately obtained by extracting the image from the image by the normal light source by spatial filtering or the like and obtaining the intersections by superimposing the light-section line images to determine the plate thickness and the crossing angle of the plate material. Since the gap, step, and crossing position are calculated from the data, the optimum welding position is determined. Therefore, the welding current value and the filler feed amount can be determined by the gap and the step, and the welding torch can be controlled to the optimum position by the crossing position to perform complete welding.

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 8.

In FIG. 1, 1 and 2 in the drawing are plate materials, and in order to weld these plate materials 1 and 2 to a corner joint (corner joint),
As shown in FIG. 2, the plate materials 1 and 2 are combined at a predetermined intersection angle, the CCD camera 3 is arranged above the combination (on the bisector of the intersection angle), and the CCD camera 3 is provided with an optical axis. On the other hand, the measurement is performed by a light cutting method in which the semiconductor laser 4 is provided on the bisector of the intersection angle in the 45 ° direction and the semiconductor laser light is irradiated. FIG. 3 is an enlarged view of a main part of the light cutting method, and the intersection with the edge of the plate 1 is P and the intersection with the edge of the plate 2 is Q in the light cutting line image. In addition, plate material 1
The gap between the end face of the plate material 2 and the side surface of the plate material 2 is a, and the step provided at the intersection of the plate material 1 and the plate material 2 is b. Then, the equations of the light section line images appearing on the plate material 1 and the plate material 2 are set as follows.

y = f ₁ (x) = A ₁ x + B ₁ y = f ₂ (x) = A ₂ x + B ₂ Here, A ₁ , B ₁ , A ₂ , and B ₂ are arbitrary constants.

Next, how to obtain the position coordinates P and Q of the edge portion of the plate material will be described. The following two methods can be considered to obtain the position coordinates P and Q.

The first method is a method of differentiating an optical cutting line image obtained by irradiating a semiconductor laser beam to obtain position coordinates P and Q of an edge portion from an inflection point as shown in FIG. Is.

The second method is to extract the image of the edge portion of the plate shown in FIG. 5 from the image of the joint portion obtained with a normal light source, for example, by performing spatial filtering, and extract the image from the intersection point of this image and the light section line image. This is a method of obtaining the position coordinates P and Q of the edge portion.

A method of obtaining the gap a, the step b, and the intersecting position R of the plate material will be described below with reference to FIG. 6 based on the equation of the optical cutting line image obtained above and the coordinates of P and Q. In FIG. 6, when the intersection point on the extension of the light cutting line between the plate material 1 and the plate material 2 is R, it is represented by R (L ₁ : L ₂ ). L ₁ is represented by the plate thickness t of the plus plate material 2 in the gap a, and L ₂
Is a step b between the plate material 1 and the plate material 2. Further, if the crossing angle between the plate material 1 and the plate material 2 is θ, θ and t can be measured in advance and are known values. Further, letting θ ₁ and θ ₂ be the intersecting angles of the plane orthogonal to the edge line and the light cutting line, respectively, Tan θ ₁ = A ₁ / Sin (θ / 2) Tan θ ₂ = A ₂ / Sin (θ / 2).

Here, from FIG. 7 which is an arrow view of FIG. 6 and FIG. 8 which is an arrow view of B, L ₁ = | y _R −y _P | / Tan θ ₁ L ₂ = | y _R −y _Q | / It is represented by Tan θ ₂ , where y _{P is} the y coordinate of the P point y _{Q is} the y coordinate of the Q point y _R is the y coordinate of the R point.

Then, since a = L ₁ −t and b = L ₂ , the gap a and the step b can be calculated. Further, the intersection position R can be easily obtained because it is the P point and the Q point of the edge portion.

In accordance with the above-described welding position determination method, the arc current of welding is controlled stepwise by the value of the clearance a of the joint portion, and the position of the welding torch is controlled by the value of the step b and the crossing position R. High-performance corner joint welding is possible.

(Embodiment 2) Hereinafter, Embodiment 2 of the present invention will be described with reference to FIGS. 9 to 16.

In FIG. 9, 1 and 2 in the drawing are plate materials, and in order to weld these plate materials 1 and 2 to a corner joint (corner joint),
As shown in FIG. 10, the plate materials 1 and 2 are combined at a predetermined crossing angle, and the CCD camera 3 is arranged above this combination (on the bisector of the crossing angle). 2 on the bisector of the intersection angle in the θ ₁ θ ₂ direction, respectively.
The measurement is performed by a light cutting method in which a semiconductor laser 4 of a table is provided and semiconductor laser light is emitted. FIG. 11 is an enlarged view of the main part by the light cutting method, and the intersections with the edge of the plate 2 are defined as P ₁ and P _{2 in the} light cutting line image, where P ₁ and P ₂ are the intersections with the edge of the plate 1. Let Q ₁ and Q ₂ . Further, the gap between the end surface of the plate material 1 and the side surface of the plate material 2 is a, and the step provided at the intersection of the plate materials 1 and 2 is b. Then, the equations of the light section line images appearing on the plate material 1 and the plate material 2 are set as follows.

y = f ₁ (x) = A ₁ x + B ₁ y = f ₂ (x) = A ₂ x + B ₂ y = f ₃ (x) = A ₃ x + B ₃ y = f ₄ (x) = A ₄ x + B ₄ where , A ₁ , B ₁ , A ₂ , B ₂ , A ₃ , B ₃ , A ₄ ,
B ₄ is an arbitrary constant.

Next, how to obtain the position coordinates P and Q of the edge portion of the plate material will be described. The following two methods can be considered to obtain the position coordinates P and Q.

The first method is a method of differentiating an optical cutting line image obtained by irradiating a semiconductor laser beam to obtain position coordinates P and Q of an edge portion from an inflection point as shown in FIG. Is.

The second method is to extract the image of the edge of the plate shown in Fig. 13 from the image of the joint obtained with a normal light source, for example, by performing spatial filtering, and then extract the image from the intersection of this image and the light section line image. This is a method of obtaining the position coordinates P and Q of the edge portion.

From the coordinates of P ₁ , P ₂ , Q ₁ , and Q _{2 obtained} as described above,
How to obtain the gap a, the step b, and the intersection position of the plate material No. 14
This will be described with reference to FIGS. The intersection points on the extension of the light cutting line between the plate material 1 and the plate material 2 are defined as R and S, and when the gap a and the step b are 0, they are defined as P ₁₀ , P ₂₀ , Q ₁₀ and Q ₂₀ .

From Fig. 15 Becomes

From Fig. 16 Becomes

Distance between θ ₁ , θ ₂ and P ₁₀ , P ₂₀ Distance of Q _10, Q ₂₀ Is known, so the distance of P ₁ P ₂ Q ₁ Q ₂ distance By measuring, the gap a and the step b can be obtained. Further, the intersecting positions can be easily obtained because they are the points P and Q at the edge portion.

In accordance with the above-described welding position determination method, the arc current of welding is controlled stepwise by the value of the clearance a of the joint portion, and the position of the welding torch is controlled by the value of the step b and the crossing position R. High-performance corner joint welding is possible. In the method of the second embodiment, it is not necessary to obtain the intersection point R in the one-line method of the semiconductor laser 4 described in the first embodiment, Since the gap a and the step b can be obtained by measuring the distance of, there is a feature that the measurement can be performed without performing complicated calculation.

(Effects of the Invention) As described in detail above, the welding position determination method and welding method of the present invention are, firstly, joint welding of plate materials arranged so as to intersect each other at the ends of a pair of plate materials, and At the same time as detecting the position coordinates of the joint portion using the cutting method, the equation on the image processing plane of the optical cutting line image projected on the side surface of the plate is determined, and these data and the plate thickness of the plate and the plate The second is the joint welding of the plate materials arranged so as to intersect each other at the ends of the pair of plate materials by calculating the data such as the gap, step, and intersection position of the joint part of the plate material from the data of the intersection angle. At the same time as detecting the position coordinate of the joint part using the light cutting method, the equation on the image processing plane of the light cutting line projected on the side surface of the plate is obtained, and these data, the plate thickness of the plate and the plate And more of the intersection angle data In a method for determining a welding position of a plate material, the welding position of the plate material is determined by calculating data such as a gap, a step, and a crossing position of the joint portion of the plate material. Place the cutting line image at each position of the plate material (plate material 1 and plate material 2), and
Thirdly, by using the light-cutting line image of the book, at the time of detecting the position coordinates, the obtained light-cutting line agent is subjected to differential processing, and the position coordinates of the edge portion are obtained from the inflection point. Fourth, when detecting the position coordinates, the position coordinates of the edge portion of the plate material are obtained from the image of the joint portion obtained by a normal light source by means of spatial filtering or the like, so that an accurate welding position can be easily obtained. You can decide.

In addition, the welding current value, the filler feed amount, etc. as the optimum welding conditions are determined from the data of the joint part of the plate material and the step difference at the welding position thus determined, and the welding torch is set to the optimum position from the crossing position data. There is an advantage that highly reliable corner joint welding can be performed by the welding method of controlling and welding.

[Brief description of drawings]

1 to 8 show Embodiment 1 of the present invention, in which FIG. 1 is a perspective view of a corner joint portion of a plate material, FIG. 2 is a perspective view in which the plate material is subjected to an optical cutting method, and FIG. FIG. 4 is a perspective view of a main portion cut by light, FIG. 4 is a schematic drawing of how to find an inflection point by differential processing, FIG. 5 is a schematic drawing of an edge portion and a light cut image, and FIG. 6 is a welding position determining method. FIG. 7 is a perspective view of FIG. 6 taken along arrow A, FIG. 8 is a perspective view of FIG. 6 taken along arrow B, and FIGS. 9 to 16 show Embodiment 2 of the present invention. FIG. 10 is a perspective view of a corner joint portion of a plate, FIG. 10 is a perspective view in which two semiconductor lasers are used for the plate, and a light cutting method is used. FIG.
Figure is a schematic diagram of how to find the inflection point by differential processing, Figure 13 is a schematic diagram of the edge and the optical cutting line image, Figure 14 (a) is a perspective view of the method of determining the welding position, Figure 14 (b) is the same coordinate diagram, Fig. 15 is Fig. 14
16 (a) is a view on arrow A, and FIG. 16 is a view on arrow in FIG. 14 (a). 1 ... plate material 1 2 ... plate material 2 a ... gap b ... step P, Q ... position coordinates

Claims (5)

[Claims] Claim: What is claimed is: 1. In joint welding of plate members arranged so as to intersect each other at the ends of a pair of plate members, the position coordinate of the joint portion is detected by using a light cutting method, and at the same time, the light cutting is projected on the side surface of the plate members. The equation of the line image on the image processing plane is determined, and from these data and the data of the plate thickness of the plate and the crossing angle of the plate, data such as the gap, step, crossing position of the joint portion of the plate is calculated. Accordingly, the welding position of the plate material is determined, and the welding position determining method is characterized. 2. A joint welding of plate materials arranged so as to intersect each other at the end portions of a pair of plate materials, the position coordinate of the joint part is detected by using a light cutting method, and at the same time, the light cutting projected on the side surface of the plate materials. The equation of the line image on the image processing plane is determined, and from these data and the data of the plate thickness of the plate and the crossing angle of the plate, data such as the gap, step, crossing position of the joint portion of the plate is calculated. According to the method for determining the welding position of the plate material, the optical cutting line images are arranged at the respective positions (the plate material 1 and the plate material 2) of the plate material when the position coordinates are detected. Then 2
The method for determining a welding position according to claim 1, wherein an optical cutting line image of a book is used. 3. The welding according to claim 1, wherein upon detecting the position coordinates, the obtained light section image is subjected to a differential process to obtain the position coordinates of the end image portion from the inflection point. How to determine the position. 4. When detecting the position coordinates, an image of the edge portion of the plate material is extracted from the image of the joint portion obtained by a normal light source by means of spatial filtering or the like, and the intersection point of this image and the light cutting line image is extracted. The welding position determining method according to claim 1 or 2, wherein the position coordinates of the edge portion of the plate material are obtained from the above. 5. A method for determining a welding position according to claim 1, 2, 3 or 4, wherein a gap of a joint portion of the obtained plate material,
Welding current value as the optimum welding condition from the step data,
A welding method characterized in that the amount of filler, etc. is determined, and welding is performed by controlling the welding torch to the optimum position based on the intersection position data.