JP2015126660A - Welding quality inspection apparatus, and welding quality inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique which can detect the contour of a weld ball without a problem even if a surface of the weld ball is smooth.SOLUTION: A welding quality inspection apparatus 20 comprises: a camera 21 which images a weld ball 14a in a direction substantially parallel to a center axis direction C of a stator core 6 to generate image data; two inner peripheral side lighting devices 22 and two outer peripheral side lighting devices 23 which emit blue light toward the weld ball 14a and are arranged so that the blue light is reflected by the weld ball 14a and reaches the camera 21; and a contour detection part 30 which refers to the image data and detects a contour E of the weld ball 14a viewed from the camera 21 on the basis of a light emission region of the weld ball 14a due to reflection. A distance D2 between each lighting device in the center axis direction C of the stator core 6 and the stator core 6 is substantially equal or small in comparison with a distance D1 between the weld ball 14a in the center axis direction C of the stator core 6 and the stator core 6.

Description

  The present invention relates to a welding quality inspection apparatus and a welding quality inspection method.

  As this type of technology, Patent Document 1 discloses a technology for inspecting the welding quality of a welded portion where the tips of segment conductors incorporated in a stator core are welded together. In Patent Document 1, the welding spot is irradiated with light by ring illumination, and the entire weld ball is irradiated with light, while the CCD camera is used to image the welding spot, and the obtained image is analyzed to determine the gradation change rate. By detecting the large portion, the penetration correlation amount of the weld ball is calculated, and the penetration depth is obtained from the penetration correlation amount.

JP 2006-21214 A

  However, in the technique of Patent Document 1, since the imaging direction of the CCD camera and the irradiation direction of the ring illumination are substantially the same, in order to increase the gradation change rate at the contour of the weld ball, at least the surface of the weld ball As shown in FIG. 1, it is essential that the light irradiated from the ring illumination is irregularly reflected on the surface of the weld ball. Therefore, as shown in FIG. 2 of the present application, when the surface of the weld ball is smooth, the gradation change rate increases at a distance from the outline of the weld ball, and the welding correlation amount of the weld ball is accurately calculated. I can not do at all.

  The objective of this invention is providing the technique which can detect the outline of a weld ball without a problem, even if the surface of a weld ball is smooth.

According to the first aspect of the present invention, the first end portion of the first coil segment incorporated in the stator core and the second end portion of the second coil segment incorporated in the stator core are welded together. A welding quality inspection apparatus for inspecting the quality of a weld ball formed as described above, the imaging means for imaging the weld ball in a direction substantially parallel to the central axis direction of the stator core and generating image data And irradiating light toward the welding ball, and the light is arranged to be reflected by the welding ball and reach the imaging means, and referring to the image data, the reflection by the reflection A distance between the light source and the stator core in the direction of the central axis of the stator core, and a contour detection means for detecting a contour of the weld ball as viewed from the imaging means based on a light emitting area of the weld ball , As compared to the distance between the stator core and the weld ball in the central axis direction of the stator core, substantially equal, or less, the welding inspection apparatus is provided. According to the above configuration, since the light emitting region of the weld ball due to regular reflection appears in the vicinity of the contour of the weld ball viewed from the imaging unit, even if the surface of the weld ball is smooth, The outline of the weld ball viewed from the imaging means can be detected without any problem.
The welding quality inspection apparatus includes a plurality of the light sources. According to the above configuration, since the light emitting area of the weld ball due to the regular reflection is enlarged, the contour of the weld ball viewed from the imaging unit can be detected more reliably.
The plurality of light sources include an inner peripheral light source disposed on the inner peripheral side of the stator core compared to the weld ball, an outer peripheral light source disposed on the outer peripheral side of the stator core compared to the weld ball, including. According to the above configuration, since the light emitting area of the weld ball due to the regular reflection is enlarged in the radial direction of the stator core, the contour of the weld ball viewed from the imaging unit can be detected more reliably. Become.
The welding quality inspection apparatus includes a plurality of the inner peripheral side light sources. The plurality of inner peripheral light sources are arranged apart from each other in the circumferential direction of the stator core. According to the above configuration, since the light emitting area of the weld ball due to the regular reflection is expanded in the circumferential direction of the stator core, the contour of the weld ball viewed from the imaging unit can be detected more reliably. Become.
The welding quality inspection apparatus includes a plurality of the outer peripheral side light sources. The plurality of outer peripheral light sources are arranged apart from each other in the circumferential direction of the stator core. According to the above configuration, since the light emitting area of the weld ball due to the regular reflection is expanded in the circumferential direction of the stator core, the contour of the weld ball viewed from the imaging unit can be detected more reliably. Become.
The welding quality inspection apparatus further includes a luminance adjusting unit that adjusts luminance information of the image data. According to the above configuration, it is easy to extract the light emitting area of the weld ball due to the reflection from the image data.
A weld ball formed by welding a first end portion of a first coil segment incorporated in the stator core and a second end portion of a second coil segment incorporated in the stator core is attached to the stator core. According to a welding quality inspection method for inspecting the quality of the welding ball by imaging with an imaging unit in a direction substantially parallel to the central axis direction, the irradiated light is reflected by the welding ball and reaches the imaging unit. Irradiating the light toward the welding ball, and referring to the image data, and detecting the contour of the welding ball viewed from the imaging unit based on the light emission area of the welding ball due to the reflection Including the steps of: The distance between the light source of the light in the central axis direction of the stator core and the stator core is substantially equal to the distance between the weld ball and the stator core in the central axis direction of the stator core, or ,small. According to the above method, since the light emitting region of the weld ball due to regular reflection appears in the vicinity of the contour of the weld ball viewed from the imaging unit, even if the surface of the weld ball is smooth, The outline of the weld ball viewed from the imaging means can be detected without any problem.

  According to the present invention, since the light emitting area of the weld ball due to regular reflection appears in the vicinity of the contour of the weld ball viewed from the imaging means, the imaging is performed even if the surface of the weld ball is smooth. The outline of the weld ball viewed from the means can be detected without any problem.

It is a photograph which shows a mode that illumination was applied to the welding ball with a rough surface. It is a photograph which shows a mode that illumination was applied to the smooth welding ball of the surface. It is sectional drawing of a rotary electric machine. It is a perspective view of a stator. It is a fragmentary perspective view of a stator. It is a figure which shows the edge part of the coil segment which is not welded. It is a figure which shows the edge part of the welded coil segment. It is a top view of a welding quality inspection apparatus. It is a side view of a welding quality inspection apparatus. This is an inspection flow. It is a sample of image data. The image data shown in FIG. 11 is adjusted in luminance. The image data shown in FIG. It is a figure which shows a mode that a welding ball size is measured.

  As shown in FIG. 3, the rotating electrical machine 1 that is a three-phase AC motor includes a housing 2, a stator 3 (stator), a rotor 4, and a pair of bearings 5. The stator 3 is accommodated in the housing 2. The rotor 4 is disposed on the inner peripheral side of the stator 3 and is rotatably supported by the housing 2 via a pair of bearings 5.

  The rotor 4 has, for example, eight magnetic poles by including a permanent magnet.

  As shown in FIGS. 4 and 5, the stator 3 includes a stator core 6 (stator core), a three-phase stator coil 7, and a plurality of insulating papers 8. The stator core 6 is formed in a cylindrical shape by laminating a plurality of electromagnetic steel plates. A plurality of slots 9 (winding accommodation spaces) are formed in the stator core 6. The plurality of slots 9 are formed at equal intervals in the circumferential direction of the stator core 6. Each slot 9 is elongated along the central axis direction of the stator core 6. The three-phase stator coil 7 includes a plurality of U-shaped segments 11 (first coil segment, second coil segment) formed from the stator winding 10, and coils of the formed U-shaped segments 11. The end portions 13 (first end portion and second end portion) are formed by welding together. The stator winding 10 is composed of a conductor part and an insulating film part covering the conductor part. The conductor portion is typically copper. The insulating film portion is, for example, fluorine, nylon, polyamideimide, or polyphenylene sulfide. In the present embodiment, the coil end portion 13 of the U-shaped segment 11 is formed in an octagonal cross section.

  Each coil end portion 13 is a portion of the U-shaped segment 11 located outside the slot 9 as shown in FIG. In FIG. 6, the coil end portion 13 of the U-shaped segment 11 and the coil end portion 13 of another U-shaped segment 11 face each other with a slight gap in the radial direction of the stator core 6. Is shown. And the front-end | tip of the coil end part 13 of the U-shaped segment 11 and the front-end | tip of the coil end part 13 of the other U-shaped segment 11 are joined by welding as shown in FIG. That is, by simultaneously heating the tip of the coil end 13 of the U-shaped segment 11 and the tip of the coil end 13 of another U-shaped segment 11, the coil end 13 of the U-shaped segment 11, A weld ball 14 is formed between the coil end portion 13 of another U-shaped segment 11 and the weld ball 14 is connected to the coil end portion 13 of the U-shaped segment 11 and the coil of the other U-shaped segment 11. The end portion 13 is electrically connected to each other.

  Here, in order to make sure that the coil end portion 13 of the U-shaped segment 11 and the coil end portion 13 of the other U-shaped segment 11 are electrically connected to each other, the welding ball 14 is formed sufficiently large. There is a need. In order to automatically measure the size of the weld ball 14 by image processing using a camera, it is necessary to detect the contour of the weld ball 14 without any problem. As shown in FIG. 1, when the surface of the welding ball 14 is rough, when the welding ball 14 is illuminated, the light and darkness is clearly switched at the outline of the welding ball 14. However, when the surface of the weld ball 14 is smooth as shown in FIG. 2, when the weld ball 14 is illuminated, a change between light and dark does not always occur at the contour of the weld ball 14. Therefore, the inventors of the present application have developed a technique for detecting the contour of the weld ball 14 without any problem even if the surface of the weld ball 14 is smooth. The technique will be described below with reference to FIGS.

  As shown in FIGS. 8 and 9, the welding quality inspection apparatus 20 includes a camera 21 (imaging means), two inner peripheral illuminations 22 (inner peripheral light source, light source), and two outer peripheral illuminations 23 (outer periphery). Side light source, light source) and a control unit 24. 8 and 9, the weld ball 14a is the weld ball 14 to be inspected. In FIG. 8, the weld ball 14a is highlighted in black.

  The camera 21 images the welding ball 14a to be inspected and generates image data. The camera 21 outputs the generated image data to the control unit 24. As shown in FIG. 9, the camera 21 images the weld ball 14 a from a position where the weld ball 14 a is looked down. That is, the camera 21 images the welding ball 14 a in a direction substantially parallel to the central axis direction C of the stator core 6. In other words, in the side view of the stator core 6 shown in FIG. 9, the imaging direction 21a of the camera 21 and the central axis direction C of the stator core 6 are substantially parallel. In this specification, the maximum dimension in the direction orthogonal to the radial direction of the stator core 6 of the weld ball 14a in the image data imaged so as to look down on the weld ball 14a is referred to as “weld ball size F ( When the weld ball size F is equal to or greater than a predetermined value, it is evaluated that the weld ball 14a is sufficiently large and the quality of the weld ball 14a is acceptable.

  As shown in FIG. 8, the two inner-side illuminations 22 are arranged so as to irradiate the welding ball 14 a with blue light, and the blue light is reflected by the welding ball 14 a and reaches the camera 21. Yes. In the plan view of the stator core 6 shown in FIG. 8, the two inner peripheral side illuminations 22 are arranged on the inner peripheral side of the stator core 6 when viewed from the welding balls 14a. The two inner peripheral side illuminations 22 are arranged on the inner peripheral side from the stator core 6. The two inner peripheral side illuminations 22 are arranged apart from each other in the circumferential direction of the stator core 6. As shown in FIG. 9, the two inner-side illuminations 22 irradiate the welding ball 14a with blue light substantially horizontally with respect to the welding ball 14a or from a position where the welding ball 14a is looked up. In other words, the irradiation directions 22a of the two inner peripheral illuminations 22 are set to be substantially orthogonal to the central axis direction C or obliquely upward. Here, the distance between the upper end 14b of the weld ball 14a and the end surface 6a of the stator core 6 in the central axis direction C of the stator core 6 is defined as a distance D1. A distance between each inner peripheral illumination 22 and the end surface 6a of the stator core 6 in the central axis direction C of the stator core 6 is a distance D2. Specifically, the distance D2 is the base end 22b on the inner peripheral side illumination 22 side of the blue light emitted from each inner peripheral side illumination 22 and the end surface 6a of the stator core 6 in the central axis direction C of the stator core 6. And the distance between. In this case, the distance D2 is set to be substantially equal to the distance D1 or smaller than the distance D1. In the side view of the stator core 6 shown in FIG. 9, the angle between the irradiation direction 22a of each inner peripheral illumination 22 and the radial direction Q of the stator core 6 is preferably less than 30 degrees. However, the angle is positive when the irradiation direction 22a of each inner peripheral illumination 22 is obliquely upward, and the angle is zero when the irradiation direction 22a of each inner peripheral illumination 22 is horizontal. When the angle exceeds 30 degrees, the illumination from each inner peripheral illumination 22 is blocked by the stator core 6. The angle is preferably, for example, zero.

  As shown in FIG. 8, the two outer peripheral illuminations 23 are arranged so as to irradiate the welding ball 14 a with blue light and the blue light is reflected by the welding ball 14 a and reaches the camera 21. . In the plan view of the stator core 6 shown in FIG. 8, the two outer peripheral illuminations 23 are arranged on the outer peripheral side of the stator core 6 when viewed from the welding balls 14a. The two outer peripheral illuminations 23 are arranged on the outer peripheral side from the stator core 6. The two outer side illuminations 23 are arranged away from each other in the circumferential direction of the stator core 6. As shown in FIG. 9, the two outer peripheral illuminations 23 irradiate the welding ball 14a with blue light substantially horizontally with respect to the welding ball 14a or from a position where the welding ball 14a is looked up. In other words, the irradiation direction 23a of the two outer peripheral illuminations 23 is set to be substantially orthogonal to the central axis direction C or obliquely upward. Here, the distance between each outer peripheral illumination 23 and the end surface 6a of the stator core 6 in the central axis direction C of the stator core 6 is defined as a distance D3. Specifically, the distance D3 is the base end 23b on the outer peripheral side illumination 23 side of the blue light emitted from each outer peripheral side illumination 23 in the central axis direction C of the stator core 6, the end face 6a of the stator core 6, and The distance between In this case, the distance D3 is set to be substantially equal to the distance D1 or smaller than the distance D1. In the side view of the stator core 6 shown in FIG. 9, the angle between the irradiation direction 23a of each outer side illumination 23 and the radial direction Q of the stator core 6 is preferably less than 30 degrees. However, the angle is positive when the irradiation direction 23a of each outer illumination 23 is obliquely upward, and the angle is zero when the irradiation direction 23a of each outer illumination 23 is horizontal. If the angle exceeds 30 degrees, the illumination from each outer peripheral illumination 23 is blocked by the stator core 6. The angle is preferably, for example, zero.

  In FIG. 8, the control unit 24 includes a CPU (Central Processing Unit) as a central processing unit (not shown), a read / write free RAM (Random Access Memory), and a read only ROM (Read Only Memory). Then, when the CPU reads and executes the quality inspection program stored in the ROM, the quality inspection program causes the hardware such as the CPU to operate as the contour detection unit 30 (contour detection means) or the weld ball size calculation unit 31 ( (Welding ball size calculating means) and the brightness adjusting section 32 (luminance adjusting means).

  The contour detection unit 30 is a part that detects the contour E (see also FIG. 14) of the weld ball 14a with reference to the image data.

  The weld ball size calculation unit 31 is a part that calculates the weld ball size F (see also FIG. 14) of the weld ball 14 a based on the contour E detected by the contour detection unit 30. Here, the weld ball size F of the weld ball 14a is, as described above, in the direction orthogonal to the radial direction of the stator core 6 of the weld ball 14a when viewed in the central axis direction C of the stator core 6. It is defined as the maximum dimension.

  The brightness adjustment unit 32 is a part that adjusts the brightness information of the image data generated by the camera 21.

  Next, the quality inspection flow of the welding quality inspection apparatus 20 will be described with reference to FIG.

  First, as shown in FIGS. 8 and 9, the control unit 24 illuminates the welding ball 14a to be inspected using the two inner peripheral illuminations 22 and the two outer peripheral illuminations 23 (S100). Next, the control part 24 images the welding ball 14a from right above using the camera 21 (S110), and acquires the image data shown in FIG. When the photographing is completed, the control unit 24 ends the illumination (S120).

  Next, the brightness adjusting unit 32 adjusts the brightness information of the image data (S130). FIG. 12 shows the image data after adjustment. As can be seen by comparing FIG. 11 and FIG. 12, the luminance adjustment unit 32 doubles the luminance information of the image data. Here, for convenience of explanation, as shown in FIG. 13, hereinafter, it is assumed that the black and white of the adjusted image data is reversed and displayed. In FIG. 13, in particular, the light emitting region G of the weld ball 14a by regular reflection is indicated by a broken line.

  Next, the contour detection unit 30 refers to the image data shown in FIG. 13 and, based on the light emission area (including the light emission area G) of the weld ball 14a by reflection, as shown in FIG. The contour E is detected (S140).

  Then, the weld ball size calculation unit 31 calculates the weld ball size F based on the contour E detected by the contour detection unit 30 (S150).

  Finally, when the weld ball size F of the weld ball 14a obtained by the weld ball size calculation unit 31 is greater than or equal to a predetermined value, the control unit 24 passes the quality of the weld ball 14a and the weld ball size F is less than the predetermined value. If it is, the quality of the weld ball 14a is rejected (S160).

  As mentioned above, although preferred embodiment of this invention was described, the said embodiment has the following characteristics.

(1) The welding quality inspection apparatus 20 includes a coil end portion 13 (first end portion) of a U-shaped segment 11 (first coil segment) incorporated in a stator core 6 (stator core), and a stator core. The quality of the weld ball 14a formed by welding the coil end portion 13 (second end portion) of the other U-shaped segment 11 (second coil segment) incorporated in 6 is inspected. The welding quality inspection apparatus 20 includes a camera 21 (imaging means) that images the welding ball 14a in a direction substantially parallel to the central axis direction C of the stator core 6 and generates image data, and a welding ball 14a. The two inner peripheral illuminations 22 (light sources) and the two outer peripheral illuminations are arranged so that the blue light (light) is irradiated toward the camera 21 while being reflected by the welding balls 14a. 23 (light source) and a contour detection unit 30 (contour detection means) for detecting the contour E of the weld ball 14a viewed from the camera 21 based on the light emission region of the weld ball 14a by reflection with reference to the image data. Prepare. The distance D2 between each of the illuminations (two inner peripheral illuminations 22 and two outer peripheral illuminations 23) and the stator core 6 in the central axis direction C of the stator core 6 is the central axis direction C of the stator core 6. Is substantially equal to or smaller than the distance D1 between the weld ball 14a and the stator core 6. According to the above configuration, the light emitting region G of the weld ball 14a due to regular reflection appears in the vicinity of the contour E of the weld ball 14a as viewed from the camera 21, so that even if the surface of the weld ball 14a is smooth, the camera 21 The contour E of the weld ball 14a viewed from the above can be detected without any problem. Moreover, since each illumination (two inner peripheral side illumination 22 and two outer peripheral side illumination 23) irradiates light horizontally or diagonally upward, it does not illuminate the structure in the background of the welding ball 14a.
(2) The welding quality inspection apparatus 20 includes a plurality of the light sources. According to the above configuration, since the light emitting region G of the weld ball 14a due to regular reflection is enlarged, the contour E of the weld ball 14a viewed from the camera 21 can be detected more reliably.
(3) The plurality of light sources are compared with the two inner peripheral illuminations 22 (inner peripheral light sources) disposed on the inner peripheral side of the stator core 6 as compared with the weld balls 14a and the weld balls 14a. And two outer peripheral illuminations 23 (outer peripheral light sources) disposed on the outer peripheral side of the stator core 6. According to the above configuration, the light emitting region G of the weld ball 14a due to regular reflection is expanded in the radial direction of the stator core 6, so that the contour E of the weld ball 14a viewed from the camera 21 can be detected more reliably. Become.
(4) The welding quality inspection apparatus 20 includes two inner peripheral side lights 22. The two inner peripheral side illuminations 22 are arranged apart from each other in the circumferential direction of the stator core 6. According to the above configuration, the light emitting region G of the weld ball 14a due to regular reflection is expanded in the circumferential direction of the stator core 6, so that the contour E of the weld ball 14a viewed from the camera 21 can be detected more reliably. Become.
(5) The welding quality inspection device 20 includes two outer peripheral illuminations 23. The two outer side illuminations 23 are arranged away from each other in the circumferential direction of the stator core 6. According to the above configuration, the light emitting region G of the weld ball 14a due to regular reflection is expanded in the circumferential direction of the stator core 6, so that the contour E of the weld ball 14a viewed from the camera 21 can be detected more reliably. Become.
(6) The welding quality inspection apparatus 20 further includes a luminance adjusting unit 32 (luminance adjusting means) that adjusts luminance information of the image data. According to the above structure, it becomes easy to extract the light emission area (including the light emission area G) of the weld ball 14a by reflection from the image data.
(7) The coil end portion 13 of the U-shaped segment 11 incorporated in the stator core 6 and the coil end portion 13 of another U-shaped segment 11 incorporated in the stator core 6 are welded. The welding quality inspection method for inspecting the quality of the welding ball 14a by imaging the welded ball 14a with the camera 21 in a direction substantially parallel to the central axis direction C of the stator iron core 6 Irradiating the welding ball 14a with blue light so as to be reflected by the welding ball 14a and reach the camera 21 (S100), and referring to the image data, the light emitting area of the welding ball 14a by reflection (light emitting area G) (Step S140). The step (S140) of detecting the outline E of the welding ball 14a seen from the camera 21 is included. The distance D2 between the two inner peripheral illuminations 22 and the two outer peripheral illuminations 23 of the blue light in the central axial direction C of the stator core 6 and the stator core 6 is determined in the central axial direction C of the stator core 6. Compared with the distance D1 between the welding ball 14a and the stator core 6, it is substantially equal or smaller. According to the above method, since the light emitting region G of the weld ball 14a due to regular reflection appears in the vicinity of the contour E of the weld ball 14a viewed from the camera 21, even if the surface of the weld ball 14a is smooth, the camera 21 The contour E of the weld ball 14a viewed from the above can be detected without any problem.

DESCRIPTION OF SYMBOLS 1 Rotating electrical machine 2 Housing 3 Stator 4 Rotor 5 Bearing 6 Stator core 6a End surface 7 Stator coil 8 Insulating paper 9 Slot 10 Stator winding 11 U-shaped segment 13 Coil end part 14 Welding ball 14a Welding ball 14b Upper end DESCRIPTION OF SYMBOLS 20 Welding quality inspection apparatus 21 Camera 21a Imaging direction 22 Inner peripheral side illumination 22a Irradiation direction 22b Base end 23 Outer peripheral side illumination 23a Irradiation direction 23b Base end 24 Control part 30 Contour detection part 31 Welding ball size calculation part 32 Brightness adjustment part
C Center axis direction
D1 distance
D2 distance
D3 distance
E contour
F Weld ball size
G Flash area
Q radial direction

Claims (7)

Inspection of the quality of the weld ball formed by welding the first end of the first coil segment incorporated in the stator core and the second end of the second coil segment incorporated in the stator core A welding quality inspection device for
Imaging means for imaging the welding ball in a direction substantially parallel to the central axis direction of the stator core to generate image data;
A light source arranged to irradiate light toward the welding ball, and the light is reflected by the welding ball and reaches the imaging means,
Contour detection means for referring to the image data and detecting the contour of the weld ball viewed from the imaging means based on the light emission area of the weld ball due to the reflection;
With
The distance between the light source and the stator core in the central axis direction of the stator core is substantially equal to or smaller than the distance between the weld ball and the stator core in the central axis direction of the stator core. ,
Welding quality inspection device. The welding quality inspection device according to claim 1,
A plurality of the light sources,
Welding quality inspection device. The welding quality inspection device according to claim 2,
The plurality of light sources include an inner peripheral light source disposed on the inner peripheral side of the stator core compared to the weld ball, an outer peripheral light source disposed on the outer peripheral side of the stator core compared to the weld ball, including,
Welding quality inspection device. The welding quality inspection device according to claim 3,
A plurality of the inner peripheral side light sources,
The plurality of inner peripheral light sources are arranged apart in the circumferential direction of the stator core,
Welding quality inspection device. The welding quality inspection device according to claim 3 or 4,
A plurality of the outer peripheral side light sources are provided,
The plurality of outer peripheral light sources are arranged apart in the circumferential direction of the stator core,
Welding quality inspection device. The welding quality inspection device according to any one of claims 1 to 5,
Further comprising brightness adjusting means for adjusting brightness information of the image data;
Welding quality inspection device. A weld ball formed by welding a first end portion of a first coil segment incorporated in the stator core and a second end portion of a second coil segment incorporated in the stator core is attached to the stator core. A welding quality inspection method for inspecting the quality of the weld ball by imaging with an imaging means in a direction substantially parallel to the central axis direction,
Irradiating the light toward the weld ball so that the irradiated light is reflected by the weld ball and reaches the imaging means;
Referring to the image data generated by the imaging means, and detecting the outline of the weld ball viewed from the imaging means based on the light emission area of the weld ball due to the reflection;
Including
The distance between the light source of the light in the central axis direction of the stator core and the stator core is substantially equal to the distance between the weld ball and the stator core in the central axis direction of the stator core, or ,small,
Welding quality inspection method.