JP2021003726A - Welding monitoring device - Google Patents

Abstract

To provide a welding monitoring device capable of securing visibility and monitoring system even if a distance between a first camera and a second camera and an imaging object changes.SOLUTION: A welding monitoring device includes: a first camera 21 which acquires a high luminance image; a second camera 22 which is provided side by side with the first camera 21 so as to acquire a low luminance image; and a control unit 32 which has a camera control section 321 which controls both the cameras 21 and 22 and an image processing section 322 which performs synthetic processing of replacing an image at a welding portion of the high luminance image with an image at a welding portion of the low luminance image and further displays the synthetic image on a display screen 31. The control unit 32 has a position correction processing section (a portion where processing of step S6 is performed) which performs position correction of an image at a welding portion for replacing the second camera 22 according to image deviation amount Df due to a difference between installation positions of the first camera 21 and the second camera 22.SELECTED DRAWING: Figure 1

Description

The present invention relates to a welding monitor device.

Conventionally, two cameras with different characteristics are used to image the welded part and the peripheral part by arc welding, and the image of the welded part of one camera is replaced with the image of the welded part of the other camera and combined to synthesize the welded part. There are known devices for monitoring the above (see, for example, Patent Document 1 and Patent Document 2).

JP-A-2017-94364

In the technique disclosed in Patent Document 1, since the two cameras are provided in parallel, if the distance between the two cameras and the object to be imaged (welded portion) is always constant, the image of the two cameras It is possible to synthesize without shifting.

However, when the distance between the two cameras and the imaging object (welded portion) changes, the amount of deviation between the images of the two cameras changes, and the boundary between the images in the replacement portion becomes discontinuous. For this reason, the visibility may be deteriorated, which may give a sense of discomfort to the observer, and an image that accurately reflects the welding state cannot be displayed, resulting in a decrease in monitoring accuracy.

Therefore, an object of the present invention is to provide a welding monitor device capable of ensuring visibility and a monitoring system even if the distance between the first camera and the second camera and the image pickup object changes.

In order to achieve the above object, the welding monitoring device of the present invention includes a first camera that acquires a high-brightness image in which a peripheral portion of a welded portion of a work can be confirmed when performing an arc welding operation, and the first camera. A second camera that is provided side by side to acquire a low-brightness image capable of confirming the welded portion, and an image of the welded portion of the high-brightness image that controls imaging of the first camera and the second camera. Is provided with a control unit that replaces the image of the welded portion of the low-brightness image with a control unit that creates a composite image and further displays the composite image on a display screen. The control unit is the first. When replacing the image of the first camera with the image of the second camera, the replacement of the second camera is performed according to the amount of deviation of the image due to the difference in the installation position between the first camera and the second camera. It is a welding monitor device equipped with a position correction processing unit that corrects the position of an image.

In the welding monitor device of the present disclosure, it is possible to ensure visibility and a monitoring system even if the distance to the image-imaging object changes.

It is the schematic which shows the whole structure of the welding monitor apparatus of Embodiment 1. FIG. It is a front view of the welding monitor device of Embodiment 1. It is a rear view of the welding monitor device of Embodiment 1. It is a side view of the welding monitor device of Embodiment 1. FIG. It is a figure of the image taken by the welding monitor apparatus of Embodiment 1, (a) shows the image acquired by the 1st camera, and (b) shows the image acquired by the 2nd camera. It is a characteristic figure which shows the relationship between the work distance and the focus control value in the welding monitor apparatus of Embodiment 1. FIG. It is a characteristic diagram which shows the relationship between the focus control value of the 1st camera and the focus control value of a 2nd camera in the welding monitor apparatus of Embodiment 1. FIG. It is a characteristic figure which shows the relationship between the work distance in the welding monitor apparatus of Embodiment 1, and the amount of deviation between the image of a 1st camera and the image of a 2nd camera. It is a characteristic diagram which shows the relationship between the focus control value of the 1st camera and the position correction amount of the image of the 2nd camera in the welding monitor apparatus of Embodiment 1. FIG. It is a figure which shows the image acquired by the 1st camera at the time of non-welding. It is a figure which shows the image acquired by the 2nd camera at the time of non-welding. It is a flowchart which shows the flow of the process performed by the control unit of the welding monitor apparatus of Embodiment 1. FIG. It is a figure which shows the image acquired by the 1st camera at the time of welding. It is a figure which shows the image acquired by the 2nd camera at the time of welding. It is a figure which shows the composite image by the 1st synthesis method. It is a figure which shows the composite image by the 2nd synthesis method.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
The welding monitor device A of the first embodiment is used by an operator while holding it in one hand as a hand-held light-shielding surface for welding. As shown in FIG. 1, the shielding plate 10, the imaging unit 20, and the tablet computer 30 ( Hereinafter referred to as PC30).

The shielding plate 10 is formed of a metal or resin capable of shielding light and heat, and is provided on a substantially rectangular thin plate-shaped main body 11 and a lower portion of the main body 11 as shown in FIGS. 2A to 2C. A rod-shaped grip portion 12 that can be gripped by the user.

As shown in FIGS. 2A and 2C, the imaging unit 20 is provided on the front surface 11a of the main body 11 of the shielding plate 10, and includes a first camera 21 and a second camera 22 provided side by side. Further, as shown in FIG. 1, the cameras 21 and 22 are provided with optical filters 21f and 22f in the front direction (direction of the arrow FR) which is the imaging direction of the lens.

In the present specification, the direction of shooting by both cameras 21 and 22 is used as a reference, and in the drawing, the direction of the arrow FR is forward, the direction of the arrow RR in the opposite direction is backward, the direction of arrow UP is upward, and the arrow DN. The direction of is referred to as downward, the direction of arrow L is referred to as left, and the direction of arrow R is referred to as right.

As described above, the PC 30 is a tablet computer, and the display screen 31 is attached to the rear surface 11b of the main body 11 of the shielding plate 10 with the display screen 31 facing rearward (see FIGS. 2B and 2C), and the control unit 32 is provided inside.

As the display screen 31, a thin and lightweight display such as a liquid crystal display or an organic EL (electro-luminescence) display is used.

Further, the control unit 32 includes a camera control unit 321 and an image processing unit 322. Although the details will be described later, the camera control unit 321 controls the focal lengths (focus control values C1fx, C2fx) between the first camera 21 and the second camera 22, the shutter speed C1s of the first camera 21 and the like. Further, the image processing unit 322 performs a compositing process for synthesizing the images acquired by the cameras 21 and 22, displays the composite image on the display screen 31, and further, the compositing process is acquired by the second camera 22. Correct the position of the image.

In this welding monitor device A, when the first work W1 and the second work W2 are arc-welded, the operator grips the grip portion 12 and both the cameras 21 and 22 on the front surface 11a of the main body 11 are both. Welding work is performed toward the works W1 and W2 while observing the display image of the display screen 31 on the rear surface 11b. Further, FIG. 1 shows a state in which the tip of the welding wire Ww extended from the nozzle NO is melted between the first work W1 and the second work W2 to form a molten pool Mp. The portion of the molten pool Mp is a welding location and is referred to as a welding center. In the following description, when the first work W1 and the second work W2 are collectively referred to, they are simply referred to as the work W.

(Image pickup unit and control unit)
The imaging unit 20 and the control unit 32 will be described in detail below.
<Image pickup unit>
As shown in FIG. 2A, the image pickup unit 20 is provided with the first camera 21 and the second camera 22 side by side. The cameras 21 and 22 are provided with an autofocus function and a shutter speed adjustment function, and have the same shooting field of view. Therefore, it is preferable to use the same model of both cameras 21 and 22. As an example, a CMOS color image sensor having an effective pixel count of about 1920 × 1080 can be used as each of the cameras 21 and 22. Further, as the cameras 21 and 22, those having a work distance (WD: the distance from the tip of the lens to the object to be imaged when the object to be imaged is in focus) of about 100 to 300 mm are used.

The cameras 21 and 22 have a focal length measuring unit 211 and 212 for measuring the distance to the object to be imaged and a focal length control unit 221 for adjusting the focus of each camera 21 and 22 so as to obtain an autofocus function. It is provided with 222. As is well known, the focal length measuring units 211 and 221 irradiate infrared rays from the position of the lens and measure the distance by their reflection (active method), or perform distance measurement using the light that has passed through the lens. A well-known technique such as a method (passive method) is used.

The focal length control units 212 and 222 set the focus control values C1fx and C2fx for controlling the focal lengths of the cameras 21 and 22 to the distances (work distance WD) between the work W1 and W2 measured by the focal length measurement units 211 and 221. It has a function to automatically control according to the above. Further, the focal length control unit 222 of the second camera 22 controls the focal length (focus control value C2f) of the second camera 22 by controlling the camera control unit 321 of the control unit 32 in addition to the above-mentioned automatic control function. It is also possible.

The optical filters 21f and 22f are arranged in front of the lenses (not shown) of the first camera 21 and the second camera 22, respectively, to bring the imaging brightness of the first camera 21 and the second camera 22 into a predetermined range of brightness. It is for adjustment, and light-shielding glass is used. Specifically, the optical filter 21f enables the first camera 21 to acquire a high-intensity image, and is a relatively bright light-shielding glass (for example, the light-shielding degree number is within the range of 2 to 6). As an example, the light-shielding degree number 6) is used.

On the other hand, the optical filter 22f is a light-shielding glass having a sufficient light-shielding degree (for example, light-shielding degree numbers 9 to 12) so that the second camera 22 can acquire a low-luminance image in which the arc light at the time of welding and the molten pool can be confirmed. Those within the range, for example, those with a shading degree number 11) are used. As described above, since the optical filter 22f of the second camera 22 has a high light-shielding property, the image acquired by the second camera 22 becomes black on the entire surface and can be visually confirmed at the time of non-welding, as shown in FIG. 8B. I can't. Therefore, at the time of this non-welding, it is difficult for the second camera 22 to measure the distance by the focal length measuring unit 221 when the optical filter 22f is arranged in front of the lens.
Further, FIG. 8A shows an image acquired by the first camera 21 at the time of non-welding, and the work W, the nozzle NO, the welding wire Ww, and the like can be confirmed.

As the optical filters 21f and 22f, in addition to the above-mentioned light-shielding glass, a near-infrared ray transmitting type bandpass filter or a special filter in which the transmittance is changed only in the central portion can be used.

<Control unit>
Next, the contents of the processing executed by the control unit 32 will be described.
In the control unit 32, an imaging process for controlling the imaging of the cameras 21 and 22 by the camera control unit 321, a composition process for synthesizing the images captured by the cameras 21 and 22 by the image processing unit 322, and a composition process are performed. Perform position correction processing. Although details will be described later, in the imaging process, the shutter speeds C1s and C2s and the focal length (focus control values C1fx and C2fx) of the cameras 21 and 22 are controlled. Briefly, the compositing process converts the image portion of the welding center portion having white halation in the high-brightness image captured by the first camera 21 into the image of the welding center portion of the low-brightness image captured by the second camera 22. It is a process of replacing and synthesizing.

First, the image pickup process will be described. As the image pickup process, a shutter speed process and a focal length adjustment process are performed.

The shutter speed processing optimally adjusts the shutter speeds of the cameras 21 and 22, and controls the shutter speed C1s of the first camera 21 to the first shutter speed C1s1 during non-welding and the second shutter during welding. The speed is controlled to C1s2. The first shutter speed C1s1 is a speed at which an image that can confirm the surroundings of the welded portions of the workpieces W1 and W2 can be acquired at the time of non-welding. On the other hand, the second shutter speed C1s2 is faster than the first shutter speed C1s1 and, as shown in FIG. 10A, at the time of welding, the peripheral portion 21b of the halation portion 21a that caused halation at the welded portion. It is the speed at which an image that can be confirmed can be obtained.
In the shutter speed processing, the second camera 22 is controlled to a preset shutter speed C2s, which is optimal for capturing a low-luminance image, as the shutter speed processing.

Next, the focal length adjustment process will be described.
As the focal length adjusting process, a pre-stage process performed before the welding operation and a welding process performed at the time of welding are executed.

The pre-stage processing is to obtain the data and functions necessary for continuously synthesizing the images captured by the first camera 21 and the second camera 22 whose installation positions are different in the left-right direction without causing any positional deviation. It is the processing of.

This pre-stage processing is executed before the optical filters 21f and 22f are attached to the cameras 21 and 22, and the function Fcf (C1fx) for obtaining the focus control value C2fx and the function Fdf (for obtaining the position correction amount ΔDf) C1fx) is calculated.

The function Fcf (C1fx) for obtaining the focus control value C2fx and the function Fdf (C1fx) for obtaining the position correction amount ΔDf will be described below.

The function Fcf (C1fx) for obtaining the focus control value C2fx is a function for obtaining the focus control value C2fx for controlling the focal length of the second camera 22 based on the focus control value C1fx of the first camera 21. That is, the optical filter 22f of the second camera 22 has a high shielding property, and cannot output or input light rays for distance measurement through the lens at the time of non-welding. Therefore, the second camera 22 cannot control the focal length (focus control value C2f) by the autofocus function (focal length measuring unit 221).

Therefore, the focus control value C2f for controlling the focal length of the second camera 22 is set according to the focus control value C1fx obtained by the autofocus function of the first camera 21 based on the function Fcf (C1fx). ..

The procedure for obtaining this function Fcf (C1fx) will be described below.
First, as shown in FIG. 4, the focus control values C1fx and C2fx of the work distance WD and both cameras 21 and 22 are in the range of the minimum distance WD1 to the maximum distance WD2 of the work distance WD (distance between the lens and the corner c). Seeking a relationship with. The focus control value C1fx of the first camera 21 and the focus control value C2fx of the second camera 22 are control values determined based on the focal lengths measured by the focal length measuring units 211 and 221 respectively.

As shown in FIG. 4, the focus control values C1fx and C2fx are proportional to each other within the range of the minimum distance WD1 and the maximum distance WD2 of the work distance WD, and are based on the amount of deviation of the mounting positions of both cameras 21 and 22. Has a certain difference.

Therefore, the focus control value C1fx of the first camera 21 and the focus control value C2fx of the second camera 22 have a proportional relationship shown in FIG. Therefore, as shown in the following (Equation 1), the function Fcf (C1fx) for obtaining the focus control value C2fx of the second camera 22 can be obtained from the focus control value C1fx of the first camera 21.
C2fx = Fcf (C1fx) ... (Equation 1)

Next, the function Fdf (C1fx) for obtaining the position correction amount ΔDf of the acquired image of the second camera 22 will be described.

As shown in FIG. 2A, the first camera 21 and the second camera 22 are dislocated in the left-right direction on the shielding plate 10, so that the first camera 21 and the second camera 22 capture images. There is a shift in the left-right direction.

3A and 3B show an example of images captured by the first camera 21 and the second camera 22 acquired before the installation of the optical filters 21f and 22f. As shown in FIG. 3A, when the image is taken so that the corner portion c as the reference point is arranged at the center of the image of the first camera 21, the image acquired by the second camera 22 is shown in FIG. As shown in b), the position of the corner c is shifted to the left from the center of the image.

Therefore, when the image of the image at the center of the image of the first camera 21 (weld portion) is replaced with the image of the welded portion captured by the second camera 22, the image of the second camera 22 is located at a position shifted to the left from the center. It needs to be replaced with the image.

FIG. 6 shows the amount of deviation Df between the image of the first camera 21 and the image of the second camera 22 at the minimum distance WD1 and the maximum distance WD2 of the work distance WD, which is the distance from the lens to the image pickup object (work W). Shown. In this way, the deviation amount Df is proportional to the work distance WD, which is the distance between the lens and the image pickup object (reference position). The work distance WD is proportional to the focus control value C1fx, and as described above, the focus control value C2fx of the second camera 22 can be a function of the focus control value C1fx in (Equation 1).

Therefore, as shown in FIG. 7, the focus of the first camera 21 is the position correction amount ΔDf for shifting the position so that the image of the second camera 22 can be superimposed on the image of the first camera 21. It can be a function Fdf (C1fx) of the control value C1fx. The position correction amount ΔDf can be expressed by the following (Equation 2).
ΔDf = Fdf (C1fx) ... (Equation 2)

Therefore, by shifting the image of the second camera 22 shown in FIG. 3B to the right by the position correction amount ΔDf corresponding to the shift amount Df, the image of the second camera 22 is moved to the same position as the image of the first camera 21. Can be layered on. That is, in replacing a part of the image of the first camera 21 with a part of the image of the second camera 22 at the time of image composition, the image of the second camera 22 is shifted to the right by the position correction amount ΔDf. The image of the second camera 22 can be continuously combined with the image of the first camera 21 without any displacement.

Next, the processing of the control unit 32 executed at the time of welding will be described with reference to the flowchart of FIG.
In the welding monitor device A of the first embodiment, the operator grips the grip portion 12 with one hand and uses the front surface 11a of the shielding plate 10 toward the work W which is the welding portion.

At the time before welding is started (during non-welding), first, the shutter speed C1s of the first camera 21 is controlled to the first shutter speed C1s1 (step S1), and the “high brightness image” acquired by the first camera 21 is obtained. Is displayed on the display screen 31 as the base image 21A shown in FIG. 8A (step S2). The shutter speed C1s1 is a speed at which the circumference of the welded portion (center of the screen) can be confirmed during non-welding. Further, at this time, as shown in FIG. 8B, the image acquired by the second camera 22 at this time cannot be confirmed due to the shading of the optical filter 22f.

Next, the image processing unit 322 of the control unit 32 determines whether or not welding has started (step S3), and when it is determined that welding has started (during welding), the shutter speed C1s of the first camera 21 is set. At the time of welding, the shutter speed is switched to C1s2 so that the surroundings can be confirmed. Then, the acquired image is displayed as a base image (step S4). In the first embodiment, the determination during welding monitors the average brightness value C1L of the first camera 21, and starts welding when the average brightness value C1L exceeds the preset welding determination threshold value Lw. Is determined. Then, while the average brightness value C1L exceeds the welding determination threshold value Lw, it is determined that welding is in progress.

FIG. 10A shows an example of the base image 21B acquired by the first camera 21 as the shutter speed C1s2 after the start of welding. In the base image 21B displayed on the display screen 31 at the time of welding, the welding center portion becomes a halation portion 21a in which the image cannot be confirmed due to white halation. On the other hand, the peripheral portion 21b of the halation portion 21a is a dim image in which the shape and the like can be visually recognized.

At the same time, the focal length of the second camera 22 is controlled (step S5), and the position of the captured image is corrected (step S6).

As described above, the control of the focal length of the second camera 22 obtains the focus control value C2fx of the second camera 22 calculated from the focus control value C1fx of the first camera 21 based on the function Fcf (C1fx). Then, the focal length of the second camera 22 is controlled by the focus control value C2fx.

As a result, the focal length of the second camera 22 can be appropriately controlled even if the optical filter 22f having a high light-shielding property is present in front of the lens of the second camera 22.

Further, the position correction of the image captured by the second camera 22 corrects the position of the image acquired by the second camera 22 in the left-right direction by the amount of the position correction amount ΔDf described above. Since this position correction amount ΔDf is set based on the focus control value C1fx of the first camera 21, the welding monitor device A is used by hand, and even if the distance to the welding point changes, the position correction can be performed with high accuracy. It can be carried out.

FIG. 10B shows an example of an image obtained by performing the above-mentioned focal length correction and position correction on the image acquired by the second camera 22. The image 22B acquired by the second camera 22 is an image in which the welding center portion 22a can be visually recognized by the optical filter 22f, and conversely, the peripheral portion 22b cannot be visually recognized.

Next, the image acquired by the first camera 21 and the image acquired by the second camera 22 are combined, and this combined image is displayed (step S7). Here, the image of the welding center portion 22a acquired by the second camera 22 has an appropriate distance for imaging the welding center portion by the above focal length correction, and is acquired by the first camera 21 on the display screen 31. It is displayed at a position corresponding to the welding center in the base image 21B.

As the image compositing method, either one of the following first compositing method and the second compositing method is used.

In the first compositing method, in the image acquired by the first camera 21, a portion (halation portion 21a in FIG. 10A) exceeding the preset luminance threshold value is visually welded to the image 22B acquired by the second camera 22. This is a method of replacing and displaying the image of the central portion 22a. FIG. 11A shows an example of an image synthesized by this first synthesis method. Then, in performing the replacement display by this first compositing method, the size fluctuation is alleviated and the visibility is improved by using the moving average value according to the set frame as the brightness threshold value of the image of the first camera 21. Can be done.

In the second synthesis method, only the portion of the image acquired by the first camera 21 that exceeds the brightness threshold value (halation portion 21a in FIG. 10A) is averaged with the image of the welding center portion 22a acquired by the second camera 22. How to display.

FIG. 11B shows a display example of the image synthesized by the second method. That is, on the display screen 31, the image of the peripheral portion 21b of the halation portion 21a acquired by the first camera 21 is displayed surrounding the rectangular averaging region 23. Then, in the image of the averaging region 23, the image of the welding center portion 22a acquired by the second camera 22 shown in FIG. 10B and the image of the halation portion 21a (see FIG. 10A) acquired by the first camera 21 are averaged. This is the displayed image.

Then, after performing the image composition processing and the image display processing (step S7), the welding end determination is performed (step S8), and during the welding continuation, the first camera 21 and the second camera 22 are processed by the processes of steps S4 to S7. The process of synthesizing and displaying the images of is repeated. If it is determined that welding is completed, the process returns to step S1 or the image display on the display screen 31 is temporarily ended and the next predetermined start operation is waited for.

In the welding end determination, a state in which the average brightness value C1l of the image acquired by the first camera 21 is lower than the welding determination threshold value Lw described above is a more specific setting time TLw (for example, about several seconds of zero comma). If it exceeds 0.3 seconds), it is judged that welding is completed.

(Action of Embodiment 1)
Next, the operation of the welding monitor device A of the first embodiment will be described.
First, before starting welding, the operator causes the control unit 32 to perform the pre-stage processing, and obtains the function Fcf (C1fx) for obtaining the focus control value C2fx of the second camera 22 and the acquired image of the second camera 22. The function Fdf (C1fx) for obtaining the position correction amount ΔDf is calculated.

Then, when performing the welding work, the operator first holds the grip portion 12 of the welding monitoring device A, directs the front surface 11a of the main body 11 of the shielding plate 10 toward the works W1 and W2, and directs the first camera 21. And the image of the welded portion is acquired by the second camera 22.

At this time, the "high-brightness image" acquired by the first camera 21 is displayed as the base image 21A on the display screen 31 of the PC 30 provided on the rear surface 11b of the main body 11 of the shielding plate 10 (step S2). At this time, the shutter speed C1s of the first camera 21 is controlled to the first shutter speed C1s1 for non-welding.

Then, when performing arc welding, the operator points both cameras 21 and 22 toward the welded portion of the work W, and arranges the shielding plate 10 between the welded portion of the work W and the worker's face. The worker monitors the welding work by the display image of the display screen 31 of the PC 30.

Therefore, the operator can monitor the welding state by the welding monitoring device A without wearing the welding surface. Further, the light and heat of the welded portion (molten pond Mp) can be shielded by the shielding plate 10.

At the time of this welding work, the control unit 32 monitors the average brightness value C1L of the image captured by the first camera 21, and determines that welding has started when the average brightness value C1L exceeds the preset welding determination threshold value Lw. .. Further, while the average brightness value C1L exceeds the welding determination threshold value Lw, it is determined that welding is in progress (not the end of welding).

Then, when the control unit 32 determines that welding has started, the shutter speed C1s of the first camera 21 is switched to a shutter speed C1s2 which is faster than the shutter speed C1s1 before welding at the time of welding. As a result, as shown in FIG. 10A, the first camera 21 acquires an image of the peripheral portion 21b, which is an image in which the periphery of the welded portion (halation portion 21a) can be confirmed.

Further, the control unit 32 replaces and synthesizes the halation portion 21a of the first camera 21 with the image of the welding center portion 22a which is an image captured in the same region as the halation portion 21a in the image acquired by the second camera 22. .. Here, the second camera 22 is provided with an optical filter 22f made of light-shielding glass (with a light-shielding degree of about 11) having a high light-shielding degree on the front surface of the lens. Therefore, as shown in FIG. 10B, the second camera 22 can acquire a recognizable image of the welding center portion 22a having high brightness, whereas the peripheral portion 22b is acquired as an unconfirmable image. .. Therefore, in the first camera 21, the halation portion 21a that cannot be confirmed due to halation is combined with the image of the recognizable welding center portion 22a acquired by the second camera 22, and the composite image is obtained. Both the welding center portion 22a and the peripheral portion 21b thereof can be confirmed as an image.

Further, the image acquired by the second camera 22 is acquired by correcting the focal length due to the difference in the installation position based on the focus control value C1fx of the first camera 21. That is, a function for obtaining an appropriate focus control value C2fx for the second camera 22 from the focus control value C1fx of the first camera 21 based on the focal length according to the deviation of the installation position between the first camera 21 and the second camera 22. Fcf (C1fx) is obtained in advance. Therefore, even if an optical filter 22f having a high light-shielding property is provided in front of the lens of the second camera 22, an appropriate focus control value C2fx (focal length) can be calculated and controlled.

Therefore, in the composite images shown in FIGS. 11A and 11B, blurring of the image due to an inappropriate focal length between the welding center portion 22a, the averaging region 23 at the same position, and the peripheral portion 21b does not occur. As a result, the operator can confirm the state of the welding center portion 22a with high accuracy.

In addition, since the installation positions of the first camera 21 and the second camera 22 are different, the positions in the left-right direction are displaced as shown in FIGS. 3A and 3B. Therefore, when the image of the second camera 22 is combined with the image in the same range as the coordinates of the image of the first camera 21 at the time of image composition, the image of the second camera 22 is located at a position deviated from the image of the first camera 21. Will be synthesized.

Therefore, in the first embodiment, the position for shifting the position from the focus control value C1fx of the first camera 21 so that the image of the second camera 22 can be superimposed on the image of the first camera 21. The function Fdf (C1fx) for obtaining the correction amount ΔDf is calculated.

Therefore, as shown in FIGS. 11A and 11B, the welding center portion 22a and the averaging region 23 at the same position can be replaced with respect to the image of the peripheral portion 21b captured by the first camera 21 without any positional deviation. .. Therefore, the operator can confirm the state of the welding center portion 22a with high accuracy.

As described above, the worker can perform the welding work while looking at the composite image of the display screen 31 of the PC 30. In this case, as compared with the work through a single light-shielding glass, the field of view of the periphery other than the work place can be secured, the workability is excellent, and the work efficiency can be improved. Further, in the display on the display screen 31, the display magnification can be set to an arbitrary magnification, and higher visibility can be obtained as compared with the work through the light-shielding glass. In addition, as compared with the case where the work is performed while observing the welded portion through the light-shielding glass, ultraviolet rays do not transmit and the burden on the eyes of the operator can be reduced. Moreover, the heat shield due to welding can be shielded by the shielding plate, which also improves workability.

(Effect of Embodiment 1)
The effects of the welding monitoring device A of the first embodiment are listed below.
(1) The welding monitoring device A of the first embodiment has a first camera 21 and a first camera 21 that acquires a high-brightness image capable of confirming a peripheral portion 21b of a welded portion (molten pond Mp) of the work W when performing an arc welding operation. , A second camera 22 provided side by side with the first camera 21 to acquire a low-brightness image capable of confirming a welded portion (melting pond Mp), and a camera control for controlling imaging of the first camera 21 and the second camera 22. Image processing unit 322 that creates a composite image by replacing the image of the welded portion of the high-brightness image with the image of the welded portion of the low-brightness image, and further displays the composite image on the display screen 31. The control unit 32 is provided with the above.
When the control unit 32 replaces the image of the welded portion of the first camera 21 with the image of the welded portion of the second camera 22, the amount of deviation of the image due to the difference in the installation position between the first camera 21 and the second camera 22. A position correction processing unit (a portion that performs the processing in step S6) that corrects the position of the image of the welded portion where the second camera 22 is replaced is provided according to Df.
Therefore, it is possible to ensure visibility and a monitoring system without causing deviation in the composite image.

(2) In the welding monitor device A of the first embodiment, the position correction processing unit (the part that performs the processing in step S6) controls the position correction amount ΔDf at the time of position correction and the focal length of the first camera 21. It is obtained as a value corresponding to the focus control value C1fx.
Therefore, even if the distance between both cameras 21 and 22 and the work W including the welded portion (melting pond Mp) is not constant, the position correction amount ΔDf is set as the optimum value and deviates according to the change in the distance. It is possible to obtain a composite image that does not exist. As a result, even in the hand-held welding monitor device A as in the first embodiment, the composite image does not shift, and visibility and accuracy can be ensured.
To add an explanation, as shown in FIG. 2A, when the installation positions of the first camera 21 and the second camera 22 are different, the deviation amount Df differs depending on the distance from the work W. Therefore, when the position correction amount ΔDf is set to a constant value, when the distance between the cameras 21 and 22 and the work W changes, the composite image shifts, but in the first embodiment, such a problem occurs. There is nothing.

(3) The welding monitor device A of the first embodiment has an auto-focus function in which the first camera 21 and the second camera 22 measure the distance to the image-imaging object and adjust the focal length, and the control unit. 32 is a camera control unit 321 that performs the process of step S5 as a focal length control unit that obtains the focal length control value C2fx that controls the focal length of the second camera 22 from the focal length control value C1fx that controls the focal length of the first camera 21. To be equipped with.
Therefore, even if the second camera 22 has an optical filter 22f having a high light-shielding property in order to acquire a low-luminance image, the focal length of the second camera 22 can be controlled to an optimum value.

(4) In the welding monitor device A of the first embodiment, the control unit 32 has a welding determination unit (a portion of the camera control unit 321 that executes the process of step S3) for determining whether or not welding is being executed, and a first. A shutter speed control unit (a portion of the camera control unit 321 that executes the process of step S2) for controlling the shutter speed C1s of the camera 21 is provided.
Further, the control unit 32 controls the shutter speed C1s of the first camera 21 to the relatively slow first shutter speed C1s1 when the welding determination unit determines that welding is not being executed. Moreover, when the synthesis process is stopped and the welding determination unit determines that welding is in progress, the shutter speed C1s of the first camera 21 is controlled to a relatively fast second shutter speed C1s2, and the synthesis process is performed. To execute.

Therefore, at the time of non-welding, the base image 21A (see FIG. 8A) in which the work W can be confirmed is displayed on the display screen 31. On the other hand, at the time of welding, the first camera 21 acquired an image in which the welded portion could be confirmed even if halation occurred, and when combined with the image of the second camera 22, the first camera 21 acquired the image. Both the image and the image acquired by the second camera 22 can be confirmed images.
That is, when the image of the first camera 21 is acquired while welding with the first shutter speed C1s1, halation may occur in the image of the peripheral portion 21b. Further, if the first shutter speed C1s1 is set to a value corresponding to the second shutter speed C1s2 in which the peripheral portion 21b can be confirmed at the time of welding, the visibility at the time of non-welding may be deteriorated. In the first embodiment, these problems can be prevented from occurring.

(5) In the welding monitor device A of the first embodiment, the welding determination unit (the portion where the process of step S3 is executed in the camera control unit 321) obtains the average luminance value C1L of the high-luminance image, and the average luminance value C1L is calculated. If it is lower than the preset welding determination value, it is determined that non-welding is in progress, and if the average brightness value C1L is higher than the welding determination value, it is determined that welding is in progress.
Therefore, based on the base image 21A acquired by the first camera 21, it is possible to determine whether non-welding or welding is in progress with high accuracy. As a result, the control switching described in (4) above can be executed at an appropriate timing.

(6) In the welding monitor device A of the first embodiment, the first camera 21 and the second camera 22 are provided on the front surface 11a of the main body 11 of the shielding plate 10 having a light-shielding property, and the display screen 31 is a shielding plate. The shielding plate 10 provided on the rear surface 11b of the main body 11 of the 10 is a grip portion 12 that can be gripped with one hand.
Therefore, the operator can perform the welding work while holding the welding monitor device A with one hand and viewing the composite image of the display screen 31. In this case, as compared with the work through a single light-shielding glass, the field of view of the periphery other than the work place can be secured, the workability is excellent, and the work efficiency can be improved. Further, in the display on the display screen 31, the display magnification can be set to an arbitrary magnification, and higher visibility can be obtained as compared with the work through the light-shielding glass. In addition, as compared with the case where the work is performed while observing the welded portion through the light-shielding glass, ultraviolet rays do not transmit and the burden on the eyes of the operator can be reduced. Moreover, the shielding plate 10 can shield the heat generated by welding, which also improves workability.

The welding monitoring device of the present disclosure has been described above based on the embodiment. However, the specific configuration of the welding monitoring device of the present disclosure is not limited to these embodiments, and the combination of the embodiments, as long as the gist of each claim is not deviated from the claims. Design changes and additions are allowed.

For example, in the embodiment, the welding monitor device of the present disclosure is provided on a shielding plate to be gripped by an operator, but the present invention is not limited to this, and it can also be used for monitoring automatic welding by a welding robot or the like. it can.

10 Shielding plate 11a Front surface 11b Rear surface 12 Grip unit 21 First camera 211 Focal length measurement unit 212 Focal length control unit 21f Optical filter 22 Second camera 221 Focal length measurement unit 222 Focal length control unit 22f Optical filter 30 Tablet computer (PC) )
31 Display screen 32 Control unit (control unit)
321 Camera control unit 322 Image processing unit A Welding monitor device C1fx (1st camera) Focus control value C1L Average brightness value C1s1 (1st) Shutter speed C1s2 (2nd) Shutter speed Df Deviation amount Fcf (C1fx) ( Focus control value C2fx) Function Fdf (C1fx) (Position correction amount ΔDf) Function Mp Welding pond W Work W1 Work W2 Work ΔDf Position correction amount

Claims (6)

The first camera that acquires a high-brightness image that allows you to check the peripheral part of the welded part of the work when performing arc welding work, and
A second camera provided side by side with the first camera to acquire a low-luminance image capable of confirming the welded portion, and a second camera.
A compositing process that controls the imaging of the first camera and the second camera and replaces the image of the welded portion of the high-luminance image with the image of the welded portion of the low-luminance image to create a composite image. A control unit that displays the composite image on the display screen,
With
When the control unit replaces the image of the first camera with the image of the second camera, the control unit responds to the amount of deviation of the image due to the difference in the installation position between the first camera and the second camera. 2 A welding monitor device including a position correction processing unit that corrects the position of the image to be replaced. In the welding monitor device according to claim 1,
The position correction processing unit is a welding monitoring device that obtains a correction amount at the time of the position correction as a value corresponding to the focal length of the first camera. In the welding monitoring device according to claim 1 or 2.
The first camera and the second camera have an autofocus function that measures the distance between the image pickup target and adjusts the focal length.
The control unit is a welding monitor device including a focal length control unit that obtains a focus control value for controlling the focal length of the second camera from a focus control value for controlling the focal length of the first camera. In the welding monitoring device according to any one of claims 1 to 3.
The control unit includes a welding determination unit that determines whether or not welding is being executed, and a shutter speed control unit that controls the shutter speed of the first camera.
Further, when the welding determination unit determines that welding is not being executed, the control unit controls the shutter speed of the first camera to a relatively slow first shutter speed, and , The synthesis process is stopped, and when the welding determination unit determines that welding is in progress, the shutter speed of the first camera is controlled to a relatively fast second shutter speed, and the synthesis process is performed. Welding monitor device to perform. In the welding monitor device according to claim 4,
The welding determination unit obtains an average brightness value of the high-luminance image, and when the average brightness value is lower than a preset welding determination value, it determines that non-welding is in progress, and the average brightness value is the welding determination value. Welding monitor device that determines that welding is in progress if it is higher than. In the welding monitor device according to any one of claims 1 to 5.
The first camera and the second camera are provided on the front surface of a shielding plate having a light-shielding property, the display screen is provided on the rear surface of the shielding plate, and the shielding plate is a grip portion that can be gripped with one hand. Welding monitoring device equipped with.