JP6341779B2 - Edge position inspection apparatus and laser welding machine using the apparatus - Google Patents

Description

  The present invention relates to an edge position inspection apparatus for inspecting whether or not an edge of one metal member in a superposed portion of two metal members is in a correct position, and a laser welding machine using the apparatus.

  Conventionally, a vehicle has been provided with a fuel supply pipe serving as a passage when fuel is supplied to a fuel tank, and the fuel supply pipe includes a long cylindrical supply pipe body having one end connected to the fuel tank, And a short cylindrical retainer connected to the other end of the oil supply pipe body. Then, a retainer is internally fitted to the other end side of the oil supply pipe body, and laser light is irradiated toward the edge on the other end side of the oil supply pipe body, thereby laser welding the oil supply pipe body and the retainer. It is becoming common to form a fuel supply pipe by joining together.

  By the way, since the laser beam irradiation diameter in laser welding is very small, if the edge of the oil supply tube body deviates in millimeters in the direction intersecting the extending direction of the edge with respect to the laser light irradiation position, the oil supply tube It is known that penetration by laser welding becomes shallow between the main body and the retainer, resulting in poor bonding.

  In order to avoid this, laser welding is performed after inspecting in advance whether or not the edge is in the correct position with respect to the irradiation position of the laser beam by using an edge detection device as disclosed in Patent Document 1, for example. It is conceivable that the occurrence of poor welding is suppressed by carrying out the above.

  The edge detection device of Patent Document 1 is for inspecting the width dimension of a wiring formed on an insulator surface in a printed circuit board, and is connected to the camera for photographing an area including the wiring on the printed circuit board. And an edge detection unit for detecting the position of the edge based on the image captured by the camera. The edge detection unit calculates the luminance value of each pixel in the captured image and extracts the luminance value of the pixel corresponding to the edge to obtain the position of the edge.

JP 2012-8619 A

  By the way, the edge detection apparatus disclosed in Patent Document 1 extracts pixels having a reflectance close to an intermediate value between two portions (insulator portion and wiring portion) having greatly different reflectances as pixels corresponding to the edge. So there are few false detections.

  However, when two overlapping metal members are objects to be photographed, it is difficult for a difference in reflectance between the metal members to occur. Therefore, an attempt is made to detect an edge at the overlapping portion of both metal members with an apparatus such as Patent Document 1. There is a risk that false detection will increase. In addition, the luminance value of each pixel in the obtained captured image may vary due to the influence of color tone variation, contamination, or edge burrs on the surface of the metal member, which may increase false detection. Therefore, it is determined whether or not the position of the edge is correct by each pixel extracted by mistake.

  The present invention has been made in view of such a point, and an object of the present invention is to perform an edge position inspection capable of accurately inspecting whether or not the position of the edge of the overlapping portion in the two metal members is in a correct position. The object is to obtain an apparatus and a laser welding machine using the apparatus.

  In order to achieve the above-described object, according to the present invention, when extracting a pixel corresponding to an edge in a photographed image, a change in luminance value is seen in each pixel arranged in order in a direction intersecting with the extending direction of the edge in the photographed image. It is characterized by that.

That is, in the first invention, a camera that captures an area in which the edge of one metal member is included in an overlapped portion of two metal members, and the position of the edge connected to the camera and based on an image captured by the camera Edge detecting means for detecting the luminance value R _x (x = 1...) By sequentially calculating the luminance of each successive pixel in a direction intersecting the edge from a predetermined position of the captured image. n: x is a plurality of pixel rows pixel _{number) V y (y = 1 ...} n: y is the luminance value calculating unit for obtaining each pixel column number) in each pixel column V _y, the pixel number x-n In the luminance change amount calculation unit for calculating the change amount C _x from the luminance value R _x−n to the luminance value R _x (where n is a predetermined natural number), and each pixel column V _y , the following expression (1 ) Whether the luminance value R _x <the set value T ₁ is satisfied, Or, the following equation (2): luminance value R _x ≧ setting value T ₁ , change amount C _x <setting value P ₁ (3) luminance value R _x ≧ setting value T ₁ , changing amount C _x > setting value P ₂ An edge pixel extraction unit that extracts a pixel with pixel number x satisfying any one of the above as an edge corresponding pixel E _y corresponding to the edge, and each edge corresponding pixel E _y extracted by the edge pixel extraction unit, or the plurality If the value E ′ _y obtained by smoothing the edge-corresponding pixel E _{y satisfies the} set value Q ₁ <E _y <set value Q ₂ , or the set value Q ₁ <E ′ _y <set value Q ₂ , the edge Is determined to be in the correct position, and it is determined that the edge is not in the correct position unless the setting value Q ₁ <E _y <setting value Q ₂ or the setting value Q ₁ <E ′ _y <setting value Q ₂ is satisfied. And an edge position determination unit.

  In the second invention, the edge position inspection apparatus according to the first invention, a laser oscillator that amplifies the light to obtain laser light, and the laser light obtained by the laser oscillator can be irradiated toward the edge Joining means having a machining head, and laser beam movement for moving the laser beam irradiated from the machining head along the extending direction of the edge by moving at least one of the metal members and the machining head with respect to the other party Means and a control means connected to the edge position inspection device, the joining means and the laser light moving means and controlling the edge position inspection device, the joining means and the laser light moving means, the control means comprising the edge position When the inspection device gives an inspection result indicating that the edge is in the correct position, an operation signal is output to the joining means and the laser beam moving means. As a result of irradiating the edge with laser light while moving at least one of the two metal members and the processing head to start joining by laser welding, the edge position inspection device detects that the edge is not in the correct position. In the case where the error occurs, a stop signal is output to the joining means and the laser beam moving means.

In a third invention, in the second invention, the edge detection means includes an average position calculation unit that calculates an average position μ with respect to the variation in the direction intersecting the edge extension direction in the plurality of calculated edge corresponding pixels E _y . And the control means outputs an operation signal to the joining means when the joining by laser welding is started, and irradiates laser light from the processing head toward the average position μ.

In the first invention, when both metal members are polymerized, a shadow is formed on the surface of the other metal member by the edge of the one metal member, so that the region where the shadow is formed has a lower reflectance than the other regions. Therefore, by finding a luminance value R _x lower than the preset setting value T ₁ , a pixel corresponding to the luminance value R _x can be extracted as a pixel corresponding to an edge. Further, to increase brightness value of all pixels of the captured image due to variations in the color tone of the imaging region in both the surface of the metal member, even in the case that it is impossible to find a low luminance values R _x than the set value T _1, the edge extension of because it sees whether dropping significantly below the set value P ₁ to change the amount C _x of luminance values R _x for each pixel aligned in a direction intersecting the direction previously set, when the luminance values of all pixels of the captured image is increased changed Also, the pixel corresponding to the edge can be reliably extracted. In addition, even when the luminance value of each pixel around the edge increases due to an abnormal increase in the reflectance of the edge due to burrs, and a luminance value R _x lower than the set value T ₁ cannot be found, because see whether the change amount C _x of luminance values R _x of the pixels arranged in the direction intersecting the extending direction rises larger than the set value P ₂ set in advance, the pixels around the edge in the captured image due to the influence of burrs Even when the luminance value does not become low, it is possible to reliably extract pixels corresponding to the edge. In this way, even if there is a disturbance factor such as variation in color tone of the shooting area on the metal member surface or burr, it is possible to prevent pixels corresponding to the edge from being erroneously extracted, so that the edge is in the correct position. Whether or not it can be correctly inspected.

  In the second invention, the laser welding can be performed in a state where the edge of one metal member in the overlapped portion of both metal members is not shifted in the direction intersecting the extending direction of the edge with respect to the irradiation position of the laser beam. Both metal members can be reliably connected by joining by laser welding. In addition, when the edge is not in the correct position, the two metal members are not joined by laser welding, so that the occurrence of defective products can be reduced and the material cost does not increase.

  In the third invention, when the laser beam is moved in the edge extending direction with respect to the edge, the irradiation position of the laser beam on the edge becomes the most balanced position over the entire area of the edge. The penetration area is widened at the part of the member extending over the entire area of the edge, so that poor penetration between the two metal members can be reliably prevented.

1 is a perspective view of a fuel filler pipe assembled by a laser welding machine according to an embodiment of the present invention, a fuel tank to which the fuel filler pipe is connected, and a fuel filler cap that turns a fuel filler opening. It is a schematic block diagram of the laser welding machine which concerns on embodiment of this invention. It is the schematic which shows the picked-up image obtained by image | photographing the area | region containing the edge in the temporary assembly pipe concerning embodiment of this invention. 6 is a graph showing results obtained by sequentially calculating the luminance of each pixel that continues in a direction intersecting an edge from a predetermined position of a captured image, where (a) shows a result in a normal state, and (b) shows a temporary result. (C) shows the result when the brightness value of all the pixels of the photographed image has increased due to the variation in the color tone of the photographing region on the surface of the assembly tube, and FIG. It is a graph which shows the result of having extracted the edge corresponding | compatible pixel in each of the several places of the edge in a temporary assembly pipe | tube. It is a cross-sectional equivalent view in the AA line of FIG. 1, and shows the state just before performing laser welding. It is a cross-sectional equivalent view in the AA line of FIG. 1, and shows the state immediately after starting laser welding.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following description of the preferred embodiment is merely exemplary in nature.

  FIG. 1 shows a fuel supply pipe 1 according to an embodiment of the present invention. The fuel refueling pipe 1 serves as a passage when fuel is supplied to a fuel tank 11 of a vehicle, and is a substantially circular cylinder having one end connected to the fuel tank 11 and the other end enlarged in diameter. And a substantially circular short cylindrical retainer 3 (metal member) connected to the enlarged diameter portion of the oil supply pipe body 2, and the other end side of the oil supply pipe body 2. The retainer 3 is fitted inside, and the edge 2b portion of the oil supply pipe body 2 is joined to the outer peripheral surface of the retainer 3 by joining by laser welding at the overlap portion of the oil supply pipe body 2 and the retainer 3. The fuel supply pipe 1 is assembled. In addition, galvanized layers 2a and 3a are formed on the outer peripheral surface and the inner peripheral surface of the oil supply pipe body 2 and the retainer 3, respectively, and the thickness of the galvanized layers 2a and 3a is exaggerated for convenience in FIGS. It is described.

  As shown in FIG. 2, one end side of the retainer 3 has a shape that gradually decreases in diameter toward the end portion, while the other end of the retainer 3 constitutes a fuel supply port 3 b of the fuel supply pipe 1. ing.

  A female spiral portion 3c is formed on the inner peripheral surface of the other end side of the retainer 3 so as to be screwed with the male spiral portion 12a of the fuel cap 12, and the fuel filler port 3b can be opened and closed by the fuel cap 12. In addition, a nozzle of a fuel gun (not shown) is inserted.

  The fuel supply pipe 1 is assembled by a laser welding machine 20 including an edge position inspection device 10 according to an embodiment of the present invention.

  As shown in FIG. 2, the laser welding machine 20 includes a rotating jig 6 (laser beam) that supports a temporary assembly pipe 1 a in which one end side of the retainer 3 is fitted inside the other end side of the oil supply pipe body 2. Moving means).

  The rotating jig 6 includes a box-shaped jig body 6a, and a servo motor 6b having a rotation axis oriented in the horizontal direction is provided inside the jig body 6a.

  A rotary shaft 6c extending substantially horizontally from the jig body 6a to the side is attached to the output shaft of the servo motor 6b. The rotary shaft 6c rotates in conjunction with the rotational drive of the servo motor 6b. It has become.

  A male spiral portion 6d that can be screwed to the female spiral portion 3c is formed on the outer peripheral surface of the rotating shaft 6c, and the male spiral portion 6d is screwed to the female spiral portion 3c of the temporary assembly tube 1a. When the servo motor 6b is driven to rotate in this state, the rotary shaft 6c rotates and the temporary assembly pipe 1a rotates around the cylinder center line (horizontal axis) of the overlapping portion of the temporary assembly pipe 1a. Yes.

  A laser oscillator 7b that amplifies the light to obtain a laser beam Lz and a laser beam Lz obtained by the laser oscillator 7b are provided on one side of the rotation jig 6 in a direction that intersects the rotation axis direction. 2b, a processing head 7a for irradiating the laser beam 2b, an optical fiber cable 7c arranged between the laser oscillator 7b and the processing head 7a and transmitting the laser beam Lz, and an electric motor for sliding the processing head 7a. The above-mentioned machining head 7a, laser oscillator 7b, optical fiber cable 7c and electric cylinder 8 constitute the joining means 7 of the present invention.

  A lens position changing mechanism 7d capable of changing the position of a condensing lens (not shown) is provided inside the processing head 7a. The lens position is shifted by the lens position changing mechanism 7d to focus the laser light Lz. The position is changed.

  The electric cylinder 8 is capable of sliding the machining head 7a in the direction of the rotation axis of the rotary jig 6, and is supported by the rotary jig 6 by sliding the machining head 7a. The irradiation position of the laser beam Lz irradiated to the temporary assembly tube 1a can be changed in the tube center line direction of the temporary assembly tube 1a.

  The rotating jig 6 is slid in the direction of the rotational axis of the rotating jig 6 by the electric cylinder 8 so that the laser beam Lz is focused on the edge 2b. By rotating the temporary assembly tube 1a, the laser light Lz irradiated from the processing head 7a is moved along the extending direction of the edge 2b.

  On the other side of the rotating jig 6 in the direction intersecting the rotational axis direction, a photographing unit 9 capable of photographing the region including the edge 2b in the oil supply pipe body 2 and the retainer 3 is provided. .

    The photographing unit 9 includes a box-shaped unit main body 9a, a CCD camera 9b provided in the center of the unit main body 9a on the rotating jig 6 side, and provided around the CCD camera 9b, and the edge of the temporary assembly tube 1a. A plurality of LED light sources 9c that irradiate light around 2b, and the region including the edge 2b is continuously photographed while rotating the temporary assembly tube 1a with the rotating jig 6.

  An electronic computer 4 (edge detection means) for detecting the position of the edge 2b based on the image P taken by the CCD camera 9b is connected to the CCD camera 9b, and the edge position inspection device 10 is connected to the electronic computer 4 And the CCD camera 9b.

As shown in FIGS. 2 and 3, the electronic calculator 4 sequentially calculates the luminance value of each pixel continuous in a direction intersecting the edge from a predetermined position of the captured image P to obtain a luminance value R _x (x = 1). ... N: x is a pixel number) and has a luminance value calculation unit 4a for acquiring a plurality of pixel columns V _y (y = 1... N: y is a pixel column number).

Also, the computer 4, as shown in FIG. 4, the change in the above each pixel column V _y, the luminance value R _x-n of the pixel number x-n (n is a predetermined natural number) to the luminance values R _x and a luminance variation computation unit 4b for calculating the amount C _x respectively.

Furthermore, the electronic calculator 4 uses the following formula (1) for each pixel column V _y .
Luminance value R _x <setting value T ₁ (1)
Or the following formulas (2) and (3)
Luminance value R _x ≧ set value T ₁ , change amount C _x <set value P ₁ (2)
Luminance value R _x ≧ setting value T ₁ , change amount C _x > setting value P ₂ (3)
The pixel of any one satisfies pixel number x of has an edge pixel extracting unit 4c to be extracted as an edge corresponding pixel E _y corresponding to the edge.

In addition deletion, computer 4, as shown in FIG. 5, the edge corresponding pixel E _y difference with respect to the edge corresponding pixel E _y is abnormally large adjacent of each edge corresponding pixel E _y extracted as abnormal data (See each g part in FIG. 5) has an edge position determination unit 4d, and the edge position determination unit 4d smoothes the remaining edge-corresponding pixels E _y excluding abnormal data by a moving average method. When the obtained value E ′ _{y satisfies the} set value Q ₁ <E ′ _y <set value Q ₂ , the edge is determined to be in the correct position, while the set value Q ₁ <E ′ _y <set value Q ₂ is set. If not satisfied, it is determined that the edge 2b is not in the correct position. The set value Q ₁ and Q ₂ is a value corresponding to an arbitrary position where the position of the edge 2b is not a even bonding failure displaced in a direction intersecting the extending direction of the edge 2b with respect to the irradiation position of the laser beam Lz.

Then, the computer 4, have an average position calculation unit 4e to calculate an average position μ with respect to the direction of variation that intersects the edge extending direction at a plurality of edges corresponding pixel E _y mentioned above calculation.

  A control panel 14 (control means) for controlling each device is connected to the edge position inspection device 10, the rotating jig 6, the laser oscillator 7b, and the electric cylinder 8.

  The control panel 14 outputs an operation signal to the rotating jig 6 to rotate the temporary assembly tube 1a when the edge position inspection device 10 gives an inspection result that the edge 2b is in the correct position. The operation signal is output to the electric cylinder 8 and the machining head 7a is slid to adjust the irradiation position of the laser light Lz to the average position μ, and the operation signal is output to the laser oscillator 7b. Laser beam Lz is continuously irradiated from the processing head 7a toward the average position μ (edge 2b) to start joining by laser welding.

  On the other hand, the control panel 14 outputs a stop signal to the laser oscillator 7b and the rotating jig 6 when the edge position inspection device 10 gives an inspection result indicating that the edge 2b is not in the correct position. Is configured to terminate.

  Next, the assembly of the fuel supply pipe 1 by the laser welding machine 20 will be described.

  First, an operator fits one end side of the retainer 3 into the other end side of the oil supply pipe body 2 to make a temporary assembly pipe 1a, and also rotates the female spiral portion 3c of the retainer 3 in the temporary assembly pipe 1a. The provisional assembly tube 1 a is set on the rotating jig 6 by screwing the male spiral portion 6 d of the rotating shaft 6 c in the tool 6. Then, as shown in FIG. 6, the laser beam Lz of the machining head 7a is positioned to irradiate the edge 2b of the oil supply pipe body 2 in the temporary assembly pipe 1a from obliquely above.

  Next, the operator presses a welding start button (not shown). Then, the control panel 14 outputs an operation signal to the rotating jig 6 and the photographing unit 9, and based on the signal, the rotating jig 6 rotates the temporary assembly tube 1a once, and the CCD camera 9b The region including the edge 2b in the temporary assembly tube 1a is continuously photographed.

Next, the brightness value calculation unit 4a sequentially calculates the brightness of each pixel that continues from the predetermined position of the captured image P in the direction intersecting the edge 2b to calculate the brightness value R _x (x = 1... N: x is the pixel number). ) With a plurality of pixel columns V _y (y = 1... N: y is a pixel column number). For example, as shown in FIG. 3, the luminance value R _x of each pixel x in each pixel row V _y at a position where the captured image P is skipped by four in the extending direction of the edge 2 b is calculated.

Further, the luminance change amount calculation unit 4b, in each pixel column _{V y,} respectively calculating the luminance values _{R x-n} from the luminance value change amount _{C x} to _{R x} of the pixel number x-n (n is a predetermined natural number) To do.

Thereafter, the edge pixel extraction unit 4c performs the following expression (1) for each pixel column V _y .
Luminance value R _x <setting value T ₁ (1)
Or the following formulas (2) and (3)
Luminance value R _x ≧ set value T ₁ , change amount C _x <set value P ₁ (2)
Luminance value R _x ≧ setting value T ₁ , change amount C _x > setting value P ₂ (3)
Is extracted as an edge corresponding pixel E _y (y is a natural number) corresponding to the edge 2b.

FIG. 4A shows a predetermined pixel of a photographed image P photographed by the CCD camera 9b in a state where the reflectance in the photographing region on the surface of the temporary assembly tube 1a is generally low and there is no burr on the edge 2b. for column V _y is a graph of a result obtained by calculating the luminance values R _x for each pixel x. Usually, when the retainer 3 is fitted inside the other end of the oil supply pipe body 2, a shadow is formed on the surface of the retainer 3 by the edge 2b, so that the region where the shadow is formed has a lower reflectance than the other regions. Then, the luminance value _{R 10} of the pixel _{X 10} corresponding to the edge 2b is positioned lower than the set value _{T 1} region. Therefore, by finding a luminance value R _x lower than the preset setting value T ₁ , the pixel corresponding to the luminance value R _x can be extracted as the pixel E _y corresponding to the edge 2b.

Further, FIG. 4B shows a photograph taken with the CCD camera 9b in a state where the reflectance in the photographing region on the surface of the temporary assembly tube 1a is generally high due to a change in color tone and there is no burr on the edge 2b. for a given pixel column V _y of the image P is a graph of a result obtained by calculating the luminance values R _x for each pixel x. When the reflectance is high in the imaging area of the preassembled tube 1a surface, goes back up luminance values R _x of all the pixels of the captured image is an edge in finding the luminance values R _x lower than such a set value T ₁ of the above-described area it can not be such as to find the pixel X ₁₀ corresponding to 2b. In such a case, the luminance value R ₁₀ of the pixel X ₁₀ corresponding to the edge 2b is focused on that has dropped greatly in comparison with the luminance values R ₉ pixel X _9, the luminance value R _x of each pixel variation C _x is such that whether or not a larger drop results than the set value P ₁ set in advance, and a luminance value of the pixels of the other regions with the luminance value R ₁₀ of the pixel X ₁₀ corresponding to the edge 2b A pixel _Xn corresponding to the edge 2b is extracted by relative evaluation. Therefore, even when the luminance values of all the pixels of the photographed image increase and change, the pixel E _y corresponding to the edge 2b can be reliably extracted.

Further, FIG. 4C shows a predetermined image of a photographed image P photographed by the CCD camera 9b in a state in which the reflectance in the photographing region on the surface of the temporary assembly tube 1a is generally low and there is a burr on the edge 2b. it is a graph of a result obtained by calculating the luminance value R _x of each pixel x for the pixel column V _y. Usually, when there is a burr on the edge 2b that part only reflectance becomes too goes back up the luminance value R ₁₀ of the pixel X ₁₀ corresponding to the edge 2b, no longer located lower than the set value T ₁ region . In such a case, by focusing on the luminance value R ₁₀ of the pixel X ₁₀ corresponding to the edge 2b is raised greater than the luminance value R ₉ pixels X ₉ other region, the luminance value R of each pixel as of whether _x of variation C _x is a greater rise results than the set value P ₂ set in advance, luminance values R ₁₀ and luminance values of the pixels in the other areas of the pixel X ₁₀ corresponding to the edge 2b Are extracted relative to each other by extracting the pixel _Xn corresponding to the edge 2b. Therefore, even when the luminance value of the pixels around the edge 2b in the captured image P does not decrease due to the influence of burrs, the pixel corresponding to the edge 2b can be reliably extracted.

Thereafter, the edge position determination unit 4d, as shown in FIG. 5, the difference between the edge corresponding pixel E _y adjacent of each edge corresponding pixel E _y extracted by the abnormally large edge corresponding pixel E _y respectively as abnormal data At the same time, the remaining edge-corresponding pixels E _y are smoothed by a moving average method to obtain edge-corresponding pixels E ′ _y .

Furthermore, the edge position determination unit 4d determines that the edge 2b is in the correct position when the edge corresponding pixel E ′ _{y satisfies the} setting value Q ₁ <E ′ _y <setting value Q ₂ , while the setting value Q ₁ < If E ′ _y <set value Q ₂ is not satisfied, it is determined that the edge 2b is not in the correct position.

In addition, the average position calculation unit 4e calculates an average position μ with respect to the variation in the direction intersecting the extending direction of the edge 2b in the plurality of calculated edge corresponding pixels E ′ _y .

  When the edge position determination unit 4d gives an inspection result that the edge 2b is in the correct position, the control panel 14 outputs an operation signal to the rotating jig 6 to rotate the temporary assembly tube 1a. At the same time, the operation signal is output to the electric cylinder 8 and the machining head 7a is slid to adjust the irradiation position of the laser beam Lz to the average position μ. Further, the control panel 14 outputs an operation signal to the laser oscillator 7b and continuously irradiates the laser beam Lz from the machining head 7a toward the average position μ, thereby melting and solidifying the surface of the edge 2b and the retainer 3. Thus, the fuel supply pipe 1 is obtained by forming the annular joint W.

  On the other hand, when the edge position determination unit 4d gives an inspection result that the edge 2b is not in the correct position, a stop signal is output to the laser oscillator 7b and the rotating jig 6 to finish the joining operation.

  As described above, according to the embodiment of the present invention, pixels corresponding to the edge 2b are erroneously extracted even if there is a disturbance factor such as variation in color tone or burrs in the photographing region on the surface of the oil supply pipe body 2 or the retainer 3. Therefore, it can be correctly inspected whether or not the edge 2b is in the correct position.

  In addition, since the edge 2b of the oil supply pipe body 2 in the overlapped portion of the temporary assembly pipe 1a can be laser-welded in a state where it does not shift in the direction intersecting with the extending direction of the edge 2b with respect to the irradiation position of the laser light Lz, The oil supply pipe body 2 and the retainer 3 can be reliably connected by joining by laser welding. Further, when the edge 2b is not in the correct position, the oil supply pipe body 2 and the retainer 3 are not joined by laser welding, so that the occurrence of defective products can be reduced and the material cost does not increase.

  Further, since the laser beam Lz is irradiated toward the average position μ, when the laser beam Lz is moved in the extending direction of the edge 2b with respect to the edge 2b, the irradiation position of the laser beam Lz to the edge 2b is the edge 2b. It becomes the most well-balanced position over the entire area, and the penetration area is widened in the portion of the temporary assembly pipe 1a that extends over the entire area of the edge 2b, thereby reliably preventing the poor penetration between the oil supply pipe body 2 and the retainer 3. be able to.

In the embodiment of the present invention, the value E ′ _y obtained by smoothing each edge-corresponding pixel E _y extracted by the edge pixel extraction unit 4 c is set as the set value Q ₁ <E ′ _y <set value Q ₂ . Whether or not the edge 2b is in the correct position is determined based on whether or not it is satisfied, but whether or not the set value Q ₁ <E _y <set value Q ₂ is satisfied using the value E _y before smoothing processing Therefore, it may be determined whether or not the position of the edge 2b is correct.

  In the embodiment of the present invention, the CCD camera 9b is used in the shooting unit 9, but shooting may be performed using a CMOS camera.

  Further, in the embodiment of the present invention, the case has been described in which the retainer 3 is internally fitted to the other end side of the fuel supply pipe body 2 and the overlapping portion is connected by the annular joint W to assemble the fuel fuel supply pipe 1. The laser welding machine 20 can also be used when the fuel supply pipe 1 is assembled by connecting 3 to the other end side of the fuel supply pipe body 2 and connecting the overlapping portions with the annular joint W.

  In the embodiment of the present invention, the CCD camera 9b continuously captures the region including the edge 2b of the temporary assembly tube 1a. However, continuous imaging is not essential, and the region including the edge 2b of the temporary assembly tube 1a is defined as the edge. Images may be taken at a predetermined interval in the extending direction of 2b, or only a specific part in the region including the edge 2b of the temporary assembly tube 1a may be taken.

  In the embodiment of the present invention, the laser light Lz irradiated from the machining head 7a is moved along the extending direction of the edge 2b by rotating the temporary assembly tube 1a with the rotating jig 6, but the temporary assembly tube The laser beam Lz may be moved along the extending direction of the edge 2b by moving the machining head 7a with respect to 1a, or by moving at least one of the temporary assembly tube 1a and the machining head 7a with respect to the other party. The laser beam Lz may be moved along the extending direction of the edge 2b.

  In the embodiment of the present invention, the edge position inspection device 10 is applied to the laser welding machine 20, but it can also be used for other devices.

  Further, in the embodiment of the present invention, the laser welding machine 20 is used for assembling the fuel supply pipe 1, but, for example, when two metal plates are overlapped and the periphery of the overlapping portion is joined by laser welding. Can be used.

In the embodiments of the present invention, the position detection of the edge 2b calculates the luminance value R _x of each pixel x of each pixel column V _y of four each skip position in the extending direction of the edge 2b the captured image P are used, not limited to this, for example, the luminance value R _x of each pixel x of each pixel column V _y position adjacent one by one in the extending direction of the edge 2b to the position detection of each operation on the edge 2b Alternatively, the luminance value R ′ _x obtained by averaging the luminance values R _x of the respective pixels x in the plurality of pixel rows V _y adjacent in the extending direction of the edge 2 b may be used for detecting the position of the edge 2 b.

  The present invention is suitable for an edge position inspection apparatus that inspects whether or not the edge of one metal member in the overlapped portion of two metal members is in the correct position, and a laser welding machine using the apparatus.

2 Oil supply pipe body (metal member)
2b Edge 3 Retainer (Metal member)
4 Electronic computer (edge inspection means)
4a Luminance value calculation unit 4b Luminance change calculation unit 4c Edge pixel extraction unit 4d Edge position determination unit 4e Average position calculation unit 6 Rotating jig (laser beam moving means)
7 Joining means 7a Processing head 7b Laser oscillator 9b CCD camera 10 Edge position inspection device 14 Control panel (control means)
20 Laser welding machine

Claims (3)

A camera that captures an area in which the edge of one metal member is included in the overlapping portion of two metal members;
An edge detection means connected to the camera and detecting the position of the edge based on an image captured by the camera;
The edge detection means sequentially calculates the luminance of each pixel continuous in a direction intersecting the edge from a predetermined position of the captured image, and calculates a plurality of luminance values R _x (x = 1... N: x is a pixel number). A luminance value calculation unit respectively obtained by a pixel column V _y (y = 1... N: y is a pixel column number);
A luminance change amount calculation unit for calculating a change amount C _x from the luminance value R _x-n to the luminance value R _x of the pixel number x−n (n is a predetermined natural number) in each of the pixel columns V _y ;
In each pixel column V _y , the following expression (1)
Luminance value R _x <setting value T ₁ (1)
Or the following formulas (2) and (3)
Luminance value R _x ≧ set value T ₁ , change amount C _x <set value P ₁ (2)
Luminance value R _x ≧ setting value T ₁ , change amount C _x > setting value P ₂ (3)
An edge pixel extraction unit that extracts a pixel having a pixel number x satisfying any one of the above as an edge corresponding pixel E _y corresponding to the edge;
The edge pixel extracting unit each edge corresponding pixel E _y extracted _by, or the plurality of edges corresponding pixel value E _'y obtained the E _y and smoothed the set value Q _{1 <E} y _<set value Q _2, Alternatively, when the set value Q ₁ <E ′ _y <set value Q ₂ is satisfied, the edge is determined to be in the correct position, while the set value Q ₁ <E _y <set value Q ₂ or the set value Q ₁ <E ′. _{y <does} not satisfy the set value Q ₂ when the edge position inspection apparatus characterized by and a and determining the edge position determination edge is not in the correct position. The edge position inspection device according to claim 1;
A laser oscillator for amplifying light to obtain laser light, and a joining means having a processing head capable of irradiating the laser light obtained by the laser oscillator toward the edge;
Laser beam moving means for moving the laser beam irradiated from the processing head along the extending direction of the edge by moving at least one of the metal members and the processing head with respect to the counterpart;
A control means for controlling the edge position inspection device, the joining means and the laser light moving means, connected to the edge position inspection device, the joining means and the laser light moving means;
The control means outputs an operation signal to the joining means and the laser beam moving means to output the both metal members and the machining head when an inspection result indicating that the edge is in a correct position is output by the edge position inspection device. When the edge position inspection device gives an inspection result indicating that the edge is not in the correct position while irradiating the edge with laser light while moving at least one of the edge, the joining means and A laser welding machine configured to output a stop signal to the laser beam moving means. In the laser welding machine according to claim 2,
The edge detection unit includes an average position calculation unit that calculates an average position μ with respect to the variation in the direction intersecting the edge extension direction in the calculated plurality of edge corresponding pixels E _y .
The control means, when starting the joining by laser welding, outputs an operation signal to the joining means and irradiates the processing head with laser light toward the average position μ.