JP2003065968A - Method for inspecting break and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically inspect whether or not a metal foil breaks when a metal rod and the metal foil are jointed by welding or the like. SOLUTION: In a work transfer system 1 provided with a welding station 4 for spot welding an electrode rod 31 and an electrode foil 41 and a detection station 5 for detecting a break of a work 10 by a break inspection apparatus, the electrode rod 31 and the electrode foil 41 jointed by welding are transferred to the detection station 5 in a state while holding the positional relation at the welding time. The break inspection apparatus is provided with a light source 51 and an optical sensor 52. A welded part of the transferred work 10 is irradiated with light from the light source. If the welded part has a break, the light passing through the breaking part is received by the optical sensor 52 and the welded part is judged to have the break.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tear inspection method and apparatus for automatically inspecting a metal foil for tearing which tends to occur when a metal rod and a metal foil are joined by welding or the like.

[0002]

2. Description of the Related Art For example, in a metal halide lamp used for general lighting or a light source for optical equipment such as a liquid crystal projector and having a small size, high luminous flux, high brightness, and long life, molybdenum foil is bonded to a tungsten electrode. The adopted configuration is adopted. The molybdenum foil is used for sealing the electrodes of the arc tube, and is joined to the tungsten electrodes by spot welding. In this welded portion, if the molybdenum foil is torn even a little, the tungsten electrode and the molybdenum foil are easily separated, and the characteristics such as high luminous flux of the lamp and long life are impaired. However, since the molybdenum foil is extremely thin, it may break during welding, which is difficult to prevent.

Therefore, conventionally, in the manufacturing process of the metal halide lamp, the breakage is detected by visually observing the joint portion between the tungsten electrode and the molybdenum foil. In addition, the visual judgment criterion of whether or not the electrode foil is broken is that the electrode foil is torn when the electrode rod-like object is seen from the electrode foil side.

[0004]

However, the above-described visual detection method has a problem that it is difficult to detect when the breakage of the electrode foil is minute and an erroneous judgment is made. Such a problem does not occur only when the electrode rod and the electrode foil used in the lamp are joined, and also when other metal rods and the metal foil used in other cases are joined. is doing.

Therefore, the present invention has been made in view of the above problems, and provides a tear inspection method and an apparatus thereof capable of automatically determining whether or not a metal foil is torn. The purpose is to provide.

[0006]

In order to achieve the above object, a tear inspection apparatus according to the present invention comprises a welding station for welding a metal rod with a metal foil placed in a predetermined positional relationship, and a welding posture. The welded work is conveyed in the state of being kept, and a detection station for optically detecting the weld breakage is provided.The detection station is provided with a light source at a relevant position for irradiating the welding equivalent part of the welded work. An optical sensor is arranged in a positional relationship of receiving light from the light source when the welded work is broken.

With such a structure, it is possible to directly irradiate the welding-corresponding portion of the work with light, and the light sensor receives the light. Therefore, it is possible to automatically perform a tear inspection. Further, in the fracture inspection method for optically detecting weld fracture in the detection station, a light source is arranged at a relevant position for irradiating a welding equivalent portion of a welded work, and light from the light source is received by a light receiving sensor to perform welding. Inspect the finished workpiece for tears.

The tear inspection apparatus according to the present invention is a tear inspection apparatus for a welded work piece in which a metal foil is welded to a metal rod in a predetermined positional relationship, and an image pickup means for picking up an image of the welded work piece, Work contour detecting means for detecting a work contour targeting a work image obtained by imaging, search means for searching whether or not there is a non-work image area having a predetermined area or more in the detected work contour, and a search result. Therefore, it is characterized in that it is provided with a judging means for judging the breakage of the work.

With such a structure, even if the work is distorted, it is possible to accurately detect the breakage.
Further, the breakage inspection method with such a configuration has an imaging step for imaging a welded work, a work contour detection step for detecting a work contour for a work image obtained by the imaging, and a constant work within the detected work contour. A search step for searching whether or not there is a non-work image area equal to or larger than the area, and a determination step for performing work break determination according to the search result are provided.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, in the embodiment of the breakage inspection apparatus using the breakage inspection method according to the present invention, the case where the electrode rod and the electrode foil are joined by spot welding is applied and the drawings are referred to. While explaining. <First Embodiment> (Overall Configuration) FIG. 1 is a diagram showing an overall configuration of a work transfer system 1 including a tear inspection device.

As shown in FIG. 1, the work transfer system 1 has a structure in which various work robots, inspection devices, carry-out conveyors, etc. are arranged at respective work stations around a circular rotary table 2. The work stations include an electrode rod supply station 3, a welding station 4,
There are a detection station 5, a defect detection station 6 and a carry-out station 7.

An electrode rod supply robot 32 is arranged at the electrode rod supply station 3, and a welding station 4 is provided at the welding station 4.
An electrode foil supply robot 42 and a welding robot 43 are arranged. The detection station 5 has a tear inspection device, and the defect detection station 6 has a defective stocker 6a.
Each of the carry-out stations 7 is provided with a belt conveyor 7a.

The rotary table 2 is provided with fixing jigs 21 to 28 for fixing the electrode rods and a stepping motor 20, and the fixing jigs 21 to 28 are arranged along the circumferential direction on the rotary table 2. It is attached at equal intervals at an angle of 45 °. Each station is around the rotary table 2 at an angle of 45 ° at equal intervals so as to correspond to the fixing jigs 21 to 28. The stepping motor 20 moves by 45 ° to intermittently rotate the rotary table 2 in order to convey the fixing jigs 21 to 28 to each station.

The fixing jigs 21 to 28 are, as shown in FIG. 2, a main body 210 and a pressing portion 2 which are substantially C-shaped.
21, 222, etc. The lower surface 211 of the body 210,
V-shaped groove 213 is formed in 212, and electrode rod 31 is placed in this groove 213 by electrode rod supply robot 32. On the upper surface of the main body 210, the pneumatic cylinder 2
20, holding portions 221, 222 and holding rods 224, 225 for keeping the holding portions horizontal are provided, and the holding portions 221, 222 are formed with V-shaped grooves 223. By driving the pneumatic cylinder 220, the holding portions 224, 225 actuate the holding portions 221 and 222 up and down, and when the electrode rod 31 is placed in the groove 213 on the lower surface, the electrode rod 31 is held and fixed from above. It is supposed to do.

Returning to FIG. 1, in the electrode rod supply station 3, an articulated manipulator is used as the electrode rod supply robot 32 to grasp and take out the electrode rod 31 from an electrode rod stock (not shown), and a fixing jig. It is conveyed to 21 and placed in the groove 213. The electrode rod 31 fixed to the fixing jig 21 is conveyed to the welding station 4. In the welding station 4, the electrode foil supply robot 42 of the multi-joint manipulator grips the electrode foil 41 from the electrode foil stock (not shown) and, as shown in FIG. Welding robot 4 placed on rod 31
3, the electrode rod 31 and the electrode foil 41 are spot-welded. The electrode rod 31 and the electrode foil 41 (hereinafter, referred to as "workpiece 10") that are joined together are conveyed to the detection station 5 while maintaining the positional relationship during welding. Here, spot welding is a well-known technique in which base materials that have been superposed are sandwiched between electrodes whose tips are appropriately shaped, pressed, a current is applied, and the base material contact surfaces are fused by resistance heating of the contact portion. Is.

In the detection station 5, whether or not the work 10 is broken by welding is inspected by a break inspection device. The inspected work 10 is conveyed to the defect detection station 6. The details of the configuration of the breakage inspection device and the inspection method will be described later. If the workpiece 10 is broken at the defect detection station 6, the fixing jig 2
4, the work clamp is raised and the work 10 is defective stocker 6
is discharged to a. If the work 10 is not broken, the work 10 is conveyed to the carry-out station 7 while being fixed to the fixing jig, where the holding portion of the fixing jig 25 is raised, and the work 10 is conveyed as a good product by the belt conveyor 7a.

The control unit 8 is mainly composed of a CPU, controls each station and the drive unit of the rotary table 2, and causes the monitor 9 to display an error display and the like. The rotary table 2 is provided with a reference point (not shown). When the reference point reaches a predetermined position, a sensor (not shown) arranged at that position detects the reference point, and the detected signal is detected. Thus, the control unit 8 performs drive control for stopping the fixing jigs 21 to 28 at each station.

(Structure and Operation of Breakage Inspection Device) As shown in FIG. 3, the breakage inspection device includes a light source 51 for irradiating the welded portion of the work 10 with light and a broken portion if there is a breakage in the welded portion. Light that has passed (hereinafter referred to as "leakage light") 53
The optical sensor 52 for detecting the, the control unit 8, and the monitor 9
Consists of. The welding position is the welding station 4 described above.
In the above, since the work 10 is conveyed to the detection station 5 at the position rotated by 45 ° while maintaining the positional relationship at the time of welding, it can be easily determined.

The arrangement of the light source 51 for irradiating the welded portion of the work 10 with light will be described with reference to FIG. Figure 4
4A shows a state where the work 10 is broken by spot welding, and FIG. 4B shows a state where the work 10 is broken.
FIG. 6 is a cross-sectional view of the light source 51 and an optical sensor 52 with respect to the work 10 when viewed from the direction A of FIG.

As shown in FIG. 4 (b), the tear portion 45 is
It is formed on the electrode foil 41, which is slightly displaced from the joining position between the electrode rod 31 and the electrode foil 41. This is because when spot welding, welding conditions such as a contact area between the electrode rod 31 and the electrode foil 41, a pressing force according to their materials, an energizing time, and a value of electric current are set in advance, and This is because if welding is carried out at a position that is slightly off, pressure is applied to the electrode foil 41, and the electrode foil is extremely thin, causing cracks and tears.

In order to irradiate such a broken portion 45 with light, the light source 51 is perpendicular to the longitudinal direction of the electrode rod 31 and at the joining position of the electrode foil 41, as shown in FIG. It is arranged so as to irradiate light toward the welding position from diagonally below about 45 degrees. The optical sensor 52 is arranged so as to receive the leak light 53. Next, the control operation of the breakage inspection device of the control unit 8 will be described based on the flowchart of FIG.

First, when the fixing jig stops at the detection station 5 in step S11 of FIG.
The welded part of is irradiated with light. Next, the optical sensor 52 is turned on, leak light is detected, and it is determined whether there is leak light (steps S12 and S13). This can be determined by whether the control unit 8 has received the electric signal transmitted from the optical sensor 52. If there is leak light, the work 10
Is broken, and a flag indicating this is set as a defective product (Y in step S13, S14). If there is no leak light, the work 10 is flagged as a non-defective product (N in step S13, S15). The control unit 8
By referring to the state of this flag, since the holding portion of the fixing jig is raised at the defect detection station 6 or the carry-out station 7, the work 10 is conveyed as a defective product and a non-defective product.

<Second Embodiment> In the above-described embodiment, when the work is irradiated with light, the light sensor receives the light that has passed through the breakage portion to detect the breakage. In the embodiment, the break is detected by capturing an image of the work with a CCD camera and extracting the number of pixels of the light passing through the break portion by image processing.

FIG. 6 is a block diagram of a breakage inspection apparatus using a CCD camera, and those having the same numbers as those in FIG. 3 have the same configuration (the same applies to the following drawings). . As shown in the figure, the image of the work 10 captured by the CCD camera 60 is sent to the control unit 61 and subjected to image processing. The configuration of the control unit 61 is shown in FIG. 7, and as shown in FIG. 7, the control unit 61 includes a CPU 62, an A / D conversion unit 63, a binarization processing unit 64, an image memory 65, an image processing unit 66, a RAM 67, and the like. Consists of.

The A / D converter 63 converts the analog data sent from the CCD camera 60 into a digital signal. The converted digital signal is separated into an image signal and header information (a signal indicating the destination and the end of transmission), and image data 70 is generated based on the image signal. The image data 70 is sent to the binarization processing unit 64, and the header information is stored in the CPU.
Sent to 62.

In the binarization processing unit 64, as shown in FIG. 8D, the work 10 part is black, and the work 10 is broken 45.
Image data 70 so that (including the background part) becomes white
Is binarized to generate binary image data 71. Two
The value image data 71 is stored in the image memory 65. FIG. 8A shows the image data 70 represented by the multilevel. FIG. 8B is a graph showing the luminance level at an arbitrary y value 72 near the welded portion of the image data 70, where x is the horizontal scanning direction of the CCD camera 60 and y is the vertical scanning direction. FIG. 8C is a graph in which the multivalued graph of FIG. 8B is represented by binary values 1 (white pixels) and 0 (black pixels).

The ROM 68 stores a control program for executing binarization processing and image processing.
Further, the RAM 67 temporarily stores various control variables and flags for executing the control program. C
The PU 62 is connected to the CCD camera 6 via the A / D converter 63.
Upon receiving the signal sent from 0, the necessary program is read from the ROM 68 and the binarization processing unit 64, the image processing unit 66, and the like are controlled. Further, the CPU 62 sets a flag in the RAM to temporarily store the processing result of the image processing unit 66, and transmits a video signal based on the processing result to the monitor 9.

The image processing unit 66, as shown in FIG.
In the value image data 71, the contour coordinates of the workpiece 10 are detected from the preset image data in the window frame 80 by the known contour tracing process, and the tear detection frame including the welded portion is detected according to the contour coordinates. 81 is set and the number of white pixels corresponding to the area of the torn portion 45 is detected. First, as shown in the figure, the image processing unit 66 scans the image in the window frame 80 from the upper left pixel, tracks the black pixel counterclockwise with the first encountered black pixel as a tracking start point, and completes a cycle. At that time, one contour line is extracted to detect the coordinates of the outer shape of the work 10. The contour tracking processing for detecting the outer shape coordinates is described in detail in P70 of the basic technique of image processing <Technique Introduction> (Technical Review Co., Ltd.), and therefore further description is omitted.

Next, based on the obtained external coordinates of the work 10, the position of the left corner of the electrode foil 41 on the electrode rod 31 side is set as a reference position a in the drawing, and the tear detection frame 81 is started from the reference position a. The starting point position b which is the starting point of is set. The width in the x direction and the width in the y direction are set and the tear detection frame 81 is set so that the welded portion is surely included from the start point position b. Since the welding position is predetermined, the starting point position b can be easily set, and the size including the welded portion can also be set in advance.

In order to detect the number of white pixels corresponding to the area of the breaking portion 45, the image processing portion 66 sequentially scans each pixel of the image in the breaking detection frame 81 and extracts all the pixels of the connected component of the white pixels. Then, the number of pixels is detected. Here, the connected component is a pixel in which pixels having the same value are connected to each other to form one lump, and here is a white pixel of the breaking portion 45. The extraction of pixels of connected components by the contour line tracking processing is described in detail in P258 of <Basic Techniques for Image Processing> (Technical Review Co., Ltd.).

Next, the work 1 is taken by the CCD camera 60.
The control operation of the control unit 61 when detecting whether 0 is broken will be described based on the flowchart of FIG. 10. First, in step S201 of FIG. 10, when the fixing jig stops at the detection station 5, the welded portion of the work 10 is irradiated with light. Next, the CCD camera 60 captures an image of the work 10, the analog data of the captured image is converted into a digital signal by the A / D converter 63 to generate image data 70, and the binarization processor 64 outputs 2 The value image data 71 is generated and stored in the image memory 65 (steps S202 to S205).

The binary image data 71 is read from the image memory 65, and the image processing unit 66, as described above,
The window frame 80 is set to detect the position of the outer shape of the work 10, and the tear detection frame 81 including the welded portion is set from the outer position of the work 10, and the number of white pixels corresponding to the white area in the tear detection frame 81 is set. Is detected (steps S206 to S20)
9).

Next, it is determined whether the number of white pixels in the white area is a predetermined value Ts or more (step S210). The predetermined value Ts is set to be larger than the number of white pixels corresponding to the noise of the CCD in the breakage detection frame 81, and the number of pixels of noise is, for example, as a preliminary experiment, under the same conditions (exposure time and light CC to be used in
It can be determined by imaging the electrode foil which is not broken by the D camera.

If the number of white pixels in the breakage detection frame 81 is equal to or larger than the predetermined value Ts in this step S210, the work 10 has a breakage, and a flag indicating this is set in the RAM 67 as a defective product (step S210). So Y, S
211). If the number of white pixels is less than the predetermined value Ts, the workpiece 10 is flagged as a non-defective item in the RAM 67 (N in step S210, S212). Control unit 6
1 refers to the state of this flag to raise the holding portion of the fixing jig at the defect detection station 6 or the carry-out station 7,
Are classified as defective and non-defective.

By thus imaging the work 10 with the CCD camera, even when the electrode foil is distorted by welding, the outer shape coordinates of the work are detected by image processing, and then the tear detection frame 81 including the welded portion is set. Therefore, the breakage of the electrode foil due to the welding of the work 10 can be reliably detected. <Modification> The breakage inspection apparatus according to the present invention has been described above based on the embodiment. However, the content of the present invention is not limited to the above-described embodiment. For example, the following modifications are possible. It can also be implemented by example.

(1) In the first embodiment, the breakage inspection device is provided with a pair of light sources and optical sensors, but it may be provided with two pairs of light sources and optical sensors. Figure 1
FIG. 1 is a configuration diagram of a breakage inspection device including two pairs of light sources and an optical sensor. As shown in FIG.
Similar to No. 1, it is arranged so as to be orthogonal to the longitudinal direction of the electrode rod 31 and to irradiate light from obliquely below about 45 degrees to the joining position of the electrode foil 41 toward the welding position.
The light source 91 and the light source 51 are located symmetrically with respect to a plane perpendicular to the electrode foil 41 (shown by a chain line 95 in FIG. 11) among planes including the axis of the electrode rod 31. The optical sensor 92 is arranged to receive the leak light 93.

The control operation in the control unit 94 when the two optical sensors 52 and 92 are provided is almost the same as that of FIG. 5, and in step S13 of the figure, if the light sensor 52 does not detect the leak light ( In step S13, N), even if the optical sensor 92 is turned on, the leak light is detected. If there is leak light, the work 10 is determined to be a defective product, and if there is no leak light, it is determined to be a good product.

As described above, with the structure including the two pairs of light sources and the optical sensor, the breakage of the electrode foil 41 is prevented from occurring.
Can be detected even if it occurs on the right side or the left side. (2) In the first embodiment, the work 1
0 is fixed by a fixing jig, but as shown in FIG. 12, a rotary drive device 100 such as a stepping motor is used.
The work 10 may be fixed to the rotating jig 101 provided with, and the work 10 may be intermittently rotated.

The control operation of the control unit 102 in this case is shown in FIG.
It will be described based on the flowchart of FIG. First, in step S301, when the rotating jig stops at the detection station 5, the welding portion of the work 10 is irradiated with light. Next, turn on the optical sensor 52 to detect leak light,
It is determined whether or not there is light leakage (steps S302 and S).
303). If there is leak light, the work 10 is broken, and a flag indicating this is set as a defective product (Y in step S303, S304). If there is no leak light, the rotation driving device 100 is driven so that the workpiece 10 rotates by a constant angle θ (N in step S303, S30).
(5, S306), the process returns to step S302, and leak light is detected at that position. , This is repeated until leak light is detected (steps S302, S303,
(S305, S306) When leak light is detected, the process proceeds to step S304, and a flag indicating that is a defective product is set. Even if the work 10 returns to the initial rotation position, if no leak light is detected, a flag indicating that is good is set (Y in step S306, S307).

By rotating the work 10 in this manner, it is possible to detect the breakage in the vicinity of the joining portion between the electrode rod and the electrode foil due to welding by the pair of light sources and the optical sensor. (3) In the modified example (2), the work 10 is rotated, but the pair of light sources 51 and the optical sensor 52 may be rotated. As shown in FIG. 14, the pair of light sources 51 and the optical sensor 52 are used as a rotation driving device 1 such as a stepping motor.
It is fixed to a fixing jig 111 for maintaining the positional relationship between the light source 51 provided with 10 and the optical sensor 52, and intermittently rotates around the work 10.

The control operation of the control unit 112 in this case is the work 1 in steps S305 and S306 in FIG.
Instead of the rotary drive device 100 that rotates 0, the light source 5
1 and the rotation driving device 110 that rotates the optical sensor 52 are driven to rotate by a constant angle θ. Since other operations are the same, the description is omitted. Rotating the light source 51 and the optical sensor 52 in this manner is suitable when the mass and size of the work 10 is larger than the light source 51 and the optical sensor 52. With such a configuration, at the welding position. Leakage light can be detected near the joint between the electrode rod and the electrode foil.

(4) In the modification (2), the work 10 is configured to rotate intermittently.
As shown in FIG. 7, a linear drive device 121 such as a combination of a ball screw and a nut may be further provided so that the work 10 rotates intermittently and slides in the longitudinal direction of the electrode rod 31. The control operation of the control unit 123 in this case is shown in the flowchart of FIG.

The operations of steps S401 to S406 in the figure are the same as steps S301 to S306 of FIG. When the work 10 returns to the initial rotation position (Y in step S406), the linear drive device 121 is driven so as to move the electrode rod 31 in the longitudinal direction by a predetermined distance L (step S40).
7) Returning to step S402, the leak light is detected by the optical sensor, and if the leak light is not detected, the leak light is detected by rotating the position by a constant angle θ (steps S403-). S406). If no leak light is detected, steps S402 to S407 are repeated until the distance from the initial position becomes L1. Even if the workpiece 10 at the position of the distance L1 rotates 360 degrees at that position, if no leak light is detected, a flag indicating that is good is set (Y in step S408, S40).
9).

By rotating and sliding the work 10 in this manner, it is possible to detect whether or not there is a wide range of breakage at the joint portion between the electrode rod and the electrode foil with a pair of light source and optical sensor. You can (5) In the modification (4), the work 10 is rotated and slid, but the pair of light sources 51 and the optical sensor 52 may be rotated and slid.

The pair of the light source 51 and the optical sensor 52 are shown in FIG.
As shown in FIG. 7, a light source 51 and a light sensor 52 each including a rotation driving device 130 such as a stepping motor and a linear driving device 131 such as a combination of a ball screw and a nut.
Is fixed to a fixing jig 132 for maintaining the positional relationship with
The workpiece 10 may be rotated intermittently and slid in the longitudinal direction of the electrode rod 31.

The control operation of the control unit 133 in this case is as follows: In FIG. 16, the work 1 in steps S405 to S408.
In place of 0, the light source 51 and the optical sensor 52 are set at a constant angle θ.
The rotary drive device 130 and the linear drive device 131 are driven so that the electrode rod 31 is slid by a predetermined distance L in the longitudinal direction. Since other operations are the same, the description is omitted.

Rotating and sliding the light source 51 and the optical sensor 52 in this manner is suitable when the mass and size of the work 10 are larger than the light source 51 and the optical sensor 52, and such a configuration is adopted. Thus, it is possible to detect leak light in a wide area where the electrode rod and the electrode foil are joined. (6) In the second embodiment, the breakage inspection device is provided with a pair of light sources and a CCD camera, but as shown in FIG. 18, it may be provided with two pairs of light sources and a CCD camera. Good.

The control operation of the control unit 141 in this case is almost the same as that of FIG. 10, and the number of white pixels corresponding to the white area (broken part) imaged by the CCD camera 60 is less than the predetermined value Ts in step S210 of FIG. If so (step S
210), the image of the work 10 is picked up by the CCD camera 140, and the same operation as steps S203 to S212 is performed. With such a configuration including the two pairs of light sources and the CCD camera, it is possible to detect the breakage of the electrode foil 41 on the right side or the left side of the electrode rod 31.

[0049]

As described above, according to the tear inspection apparatus of the present invention, a welding station for welding a metal rod with a metal foil placed in a predetermined positional relationship and a state in which the welding posture is maintained. The welded work is conveyed in the, and a detection station that optically detects weld breakage is provided.In the detection station, a light source is arranged at a relevant position that irradiates the welding equivalent part of the welded work, and the welded work is Since the optical sensor is arranged so as to receive the light from the light source when there is a break, the following effects are obtained. In other words, since the work is conveyed to the detection station while maintaining the posture during welding, it is possible to directly irradiate the light corresponding to the welding with the light from the light source and detect the light from the light source. As an optical sensor, an inexpensive sensor that can detect the presence or absence of light may be used, and it is also possible to detect minute tears in a welded work that cannot be visually detected, and unlike the manual work, the metal foil tears at high speed. It is possible to detect whether or not there is.

Further, according to the breakage inspection apparatus of the present invention, the image pickup means for picking up the image of the welded work, the work contour detection means for detecting the work contour for the work image obtained by the image pickup, and the detected work. It is characterized in that it is provided with a searching means for searching whether or not there is a non-work image area having a predetermined area or more in the contour, and a judging means for judging a work break according to the search result. With this configuration, when the welded work has some deformation such as the metal foil being distorted, even if it looks like a line visually, it is an image of the work tear as an area from the work image obtained by imaging. Since the area can be searched, it is possible to accurately detect whether or not the metal foil is broken.

Further, in the present invention, the breaking inspection method according to the present invention is also an object of the invention, and the same effect as that of the breaking inspection device can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a work transfer system according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a configuration of a fixing jig in the work transfer system.

FIG. 3 is a schematic diagram showing a configuration of a tear inspection device according to the first embodiment of the present invention.

FIG. 4 is a diagram showing the principle of the tear inspection device.

FIG. 5 is a flowchart showing a control operation of leak light detection in a control unit of the breakage inspection device.

FIG. 6 is a schematic diagram showing a configuration of a tear inspection device according to a second embodiment of the present invention.

FIG. 7 is a block diagram of a control unit in the breakage inspection device.

FIG. 8 is a diagram of image 2 in the binarization processing unit in the control unit.
It is a figure which shows valuation.

FIG. 9 is a diagram showing a processing method in an image processing unit in the control unit.

FIG. 10 is a flowchart showing a control operation of white area detection in the control unit of the tear inspection device.

FIG. 11 is a schematic diagram showing a configuration of a breakage inspection apparatus including two pairs of light sources and an optical sensor.

FIG. 12 is a schematic diagram showing a configuration when a work is fixed to a rotating jig equipped with a rotation driving device and rotated.

FIG. 13 is a flowchart showing a control operation of leak light detection of a control unit when rotating a work.

FIG. 14 is a schematic diagram showing a configuration in which a pair of light sources and an optical sensor are fixed and rotated by a fixing jig provided with a rotation driving device.

FIG. 15 is a schematic diagram showing a configuration in which a work is fixed to a rotating jig equipped with a rotation driving device and a linear driving device, and is rotated and slid.

FIG. 16 is a flowchart showing a control operation of leak light detection of a control unit when rotating and sliding a work.

FIG. 17 is a schematic diagram showing a configuration in which a pair of light sources and an optical sensor are fixed to a fixing jig having a rotation driving device and a linear driving device, and are rotated and slid.

FIG. 18 is a schematic diagram showing a configuration of a breakage inspection device including two pairs of light sources and a CCD camera.

[Explanation of symbols]

1 Work transfer system 4 welding station 5 detection stations 10 work 21-28 Fixing jig 31 electrode rod 41 electrode foil 45 Breaking part 51, 91 light source 52,92 Optical sensor 53, 93 leak light 60, 140 CCD camera 62 CPU 63 A / D converter 64 Binarization processing unit 66 Image processing unit 67 RAM 71 Binary image data 81 Break detection frame

Continued front page    F term (reference) 2F065 AA49 CC02 CC15 FF02 FF04                       HH12 JJ08 JJ26 KK01 PP13                       QQ04 QQ24 QQ31 UU04 UU05                 2G051 AA07 AA90 AB02 BA01 CA03                       CB02 DA08 DA13 EA11 EA12                       EA14 EB01 ED08 FA01

Claims (4)

[Claims] 1. A welding station for welding with a metal foil placed on a metal rod in a predetermined positional relationship, and a welded work is conveyed while maintaining a posture during welding, and welding breakage is detected optically. And a detection station, in which a light source is arranged at a relative position for irradiating a welding equivalent part of a welded work, and a positional relationship for receiving light from the light source when the welded work is broken. A tear detection device characterized in that an optical sensor is arranged in the. 2. A fracture inspection device for a welded work, comprising: welding a metal foil to a metal rod in a predetermined positional relationship; an image pickup means for picking up an image of the welded work; and a work image obtained by the image pickup. As a work contour detecting means for detecting a work contour, a searching means for searching whether or not there is a non-work image area having a predetermined area or more in the detected work contour, and a judging means for judging a work break according to the search result. And a breakage inspection device. 3. A welded work is conveyed from a welding station for welding with a metal foil placed on a metal rod in a predetermined positional relationship to an inspection station in a state where the posture during welding is maintained, and welding breakage is optically detected. In the detection station, a light source is arranged at a relative position to irradiate the welding equivalent part of the welded work, and the light from the light source is received by the light receiving sensor to the welded work. A tear inspection method characterized by inspecting whether there is a tear. 4. A method for inspecting a welded work for breaking, wherein a metal foil is welded to a metal rod in a predetermined positional relationship, the imaging step of imaging the welded work, and the work image obtained by the imaging. As a work contour detection step, a search step that searches for a non-work image area of a certain area or more within the detected work contour, and a determination step that determines work breakage according to the search result. And a breaking inspection method.