JP2007064801A - Lighting system and appearance inspection device equipped with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system capable of more certainly showing a flaw part to perform precise inspection of appearance. <P>SOLUTION: The lighting system 21 is composed of first, second and third projection mechanisms 22, 23 and 24 which are provided on an appearance inspection device for photographing an electronic component C to inspect the appearance thereof to illuminate the electronic component C at the time of photographing and are provided with a plurality of light emitting diodes 22a, 23a and 24a arranged annually respectively and irradiating light toward the electronic component C. The first, second and third projection mechanisms 22, 23 and 24 are arranged so that the annular arranging center axes of the respective light emitting diodes 22a, 23a and 24a cross a horizontal surface at right angles so as to be mutually arranged coaxially. The first, second and third projection mechanisms are respectively arranged at upper, middle and lower stages. Further, the first projection mechanism 22 emits blue light and the second and third projection mechanisms 23 and 24 emit a red light. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an illumination device that is provided in an appearance inspection apparatus that images an electronic component and inspects the appearance of the electronic component, and illuminates the electronic component when the electronic component is imaged, and an appearance inspection apparatus including the illumination device.

  2. Description of the Related Art Conventionally, as an illumination device for an appearance inspection apparatus that images a multilayer capacitor (inspection object) that is an electronic component and inspects its appearance, for example, the one disclosed in Japanese Patent Publication No. 6-78989 is known. Yes. This illuminating device illuminates a multilayer capacitor, which is appropriately transported in a predetermined transport direction by a transport device, from above. A high-intensity lamp and a hemispherical diffuse translucent provided to cover the multilayer capacitor from above. An optical fiber bundle that transmits a light from a high-intensity lamp from one end side to the other end side with a member, a high-intensity lamp at one end surface, and the other end surface spaced apart from the outer peripheral surface of the diffuse translucent member It consists of.

  The diffuse translucent member has a through-hole at the top and two cut-out openings for allowing the multilayer capacitor conveyed by the conveying device to pass in the conveying direction on the lower side. Yes. In addition, since the imaging mechanism for imaging the multilayer capacitor is disposed above the top of the diffuse translucent member, the imaging mechanism is provided for imaging the surface of the multilayer capacitor from the through hole. It is what.

  The other end side of the optical fiber bundle is branched into a plurality, and the other end surfaces of the optical fiber bundle are opposed to the outer peripheral surface of the diffuse translucent member at substantially equal intervals, and transmits the light incident from one end side to each other end surface. To the outer peripheral surface of the diffuse translucent member.

  According to this illumination device, light from the high-intensity lamp enters one end side of the optical fiber bundle and is transmitted toward the other end side by the optical fiber bundle, and then diffused light is transmitted from each other end surface. Irradiation toward the outer peripheral surface of the sex member. Then, after the light is diffused by the diffuse translucent member, the multilayer capacitor transported by the transport device is irradiated inside the diffuse translucent member.

  As described above, the other end side of the optical fiber bundle is branched into a plurality of parts so as to face the outer peripheral surface of the diffusive translucent member at substantially equal intervals, and the light irradiated from each other end surface of the optical fiber bundle is transmitted to the diffusive transmissive member. Since the light-diffusing member diffuses the multilayer capacitor, the multilayer capacitor can be illuminated uniformly from all directions.

Japanese Patent Publication No. 6-78989

  However, in the above conventional illumination device, light from a high-intensity lamp is irradiated to the multilayer capacitor so that defective portions such as cracks, scratches, chipping, laminated dielectric and internal electrode floating are conspicuous. However, it is difficult to make all of these defects stand out at the same level (i.e., there are some types of defects that can make the defective part stand out, and there are defects that cannot make the defective part stand out so much). There was a problem that there was also a kind).

  For this reason, when the appearance inspection of the multilayer capacitor is performed by the appearance inspection apparatus provided with the illumination device, an image of the multilayer capacitor picked up by the image pickup mechanism includes a case where the defective portion is not conspicuous. It was difficult to perform inspection with high accuracy.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an illuminating device that enables more accurate appearance inspection by highlighting defective portions more reliably, and an appearance inspection device including the same. And

To achieve the above object, the present invention provides:
Provided in an appearance inspection apparatus that images an electronic component and inspects its appearance, and an illumination device that illuminates the electronic component during imaging,
It has a plurality of light projecting units that irradiate light toward the electronic component, and includes a plurality of light projecting means in which each light projecting unit is arranged in an annular shape,
The light projecting means are arranged coaxially and arranged in parallel in the direction of the axis (annular arrangement center axis of the light projecting portion), and at least one of the light projecting means is another light projecting means. The illumination device is configured to irradiate light having a color different from that of the light projecting unit toward the electronic component.

  According to this illuminating device, the lighting state of each light projecting means is appropriately controlled, and among the light projecting means, light is emitted from the light projecting means that irradiates light of the same color toward the electronic component, By switching the light projecting means for irradiating light, at least two colors of light are applied to the electronic component.

  In addition, in recent studies, it has been found that when an electronic component is irradiated with light of a specific color, it is easy to make a specific defective portion stand out. This is because even if the light of one color cannot make the defective portion stand out, the light of the other color can make the defective portion stand out. Examples of the electronic component include those provided with a dielectric and internal electrodes such as a multilayer capacitor, a chip type light emitting diode, and a chip type inductor.

  Thus, according to the illumination device according to the present invention, it is possible to irradiate at least two colors of light onto an electronic component, so even if it is a defective portion that cannot be highlighted with one color of light, It can be made to stand out by irradiating the other color.

  Each of the light projecting units includes a light projecting unit that irradiates blue light from the light projecting unit toward the electronic component, and a red light that irradiates the electronic component from the light projecting unit. It is preferable that at least a light projecting unit is included.

  This is because when an electronic component is irradiated with blue light, defects such as cracks and scratches on the surface of the electronic component tend to stand out. When an electronic component is irradiated with red light, the multilayer capacitor is laminated. This is because it is easy to make a defective portion existing in the electronic component such as the dielectric and the internal electrode lift up. Therefore, if a lighting device is configured by combining the light projecting means for irradiating blue and red light, various defect portions can be more effectively made to stand out.

  Each of the light projecting means includes a first light projecting means, a second light projecting means, and a third light projecting means arranged in parallel in the axial direction, and the first light projecting means has its axis (projected). Arranged so that the irradiation optical axis of the light projecting unit is inclined by 15 ° to 35 ° with respect to the annular arrangement central axis of the optical unit), and configured to irradiate blue light toward the electronic component, The second light projecting means is disposed so that an irradiation optical axis of the light projecting unit is inclined by 40 ° to 50 ° with respect to its axis (annular arrangement center axis of the light projecting unit), and the red light is The third light projecting unit is configured to irradiate the electronic component, and the irradiation light axis of the light projecting unit is inclined by 55 ° to 75 ° with respect to its axis (annular arrangement center axis of the light projecting unit). And is preferably configured to irradiate red light toward the electronic component.

  This is caused by irradiating blue light with the irradiation optical axis of the light projecting unit inclined by 15 ° to 35 ° (55 ° to 75 ° with respect to the surface of the electronic component) from the central axis of the light projecting means, thereby causing cracks. This is because defects such as scratches and flaws existing on the surface of the electronic component can be more effectively highlighted, and the red light is emitted by 40 ° from the central axis of the light projecting unit. The multilayer capacitor is laminated by irradiating at an angle of -50 ° (40 ° -50 ° with respect to the surface of the electronic component) and 55 ° -75 ° (15 ° -35 ° with respect to the surface of the multilayer capacitor). This is because it is possible to more effectively highlight defective portions existing inside the electronic component such as floating of the dielectric and the internal electrode. Moreover, it is because it becomes easy to detect the shape defect of electronic components, such as a chip, by making the angle between an irradiation optical axis and the electronic component surface small. Also, the reason for providing two light projecting means for irradiating red light is to increase the amount of light emitted to the surface of the electronic component. Therefore, if it does as mentioned above, it will become more effective by making various defect parts stand out.

The present invention also provides:
An appearance inspection apparatus for imaging an electronic component and inspecting its appearance,
A transport mechanism for transporting the electronic component in a predetermined transport direction;
An imaging mechanism that images the surface of the electronic component that is transported by the transport mechanism and passes through the imaging region;
The illumination device according to any one of claims 1 to 3, which illuminates an electronic component conveyed in the imaging region by the conveyance mechanism;
A determination processing unit that determines the quality of the appearance of the electronic component based on the image of the electronic component imaged by the imaging mechanism;
A control unit for controlling the operation of the illumination device and the imaging mechanism,
The imaging mechanism is arranged such that its imaging optical axis is located within the arrangement ring of the light projecting portion of each of the light projecting means,
The control unit controls each light projecting unit to irradiate light from the light projecting unit that emits light of the same color among the light projecting units toward the electronic component. While passing through the imaging area, the light projecting means for irradiating light is switched to change the color of light irradiated to the electronic component, and the imaging mechanism is controlled to It is configured to image the surface of the electronic component for each color of irradiated light,
The determination processing unit is configured to perform pass / fail determination based on each image captured for each color of light irradiated on the electronic component.

  According to this appearance inspection apparatus, when the electronic component conveyed by the conveyance mechanism passes through the imaging region of the imaging mechanism, the electronic component is illuminated by the illumination device, and the surface of the electronic component is illuminated by the imaging mechanism. Imaged.

  Specifically, under the control of the control unit, first, light of a predetermined color is emitted from the light projecting unit that irradiates the same color of light to the electronic component passing through the imaging region. Irradiation is performed, and the surface of the electronic component is imaged by the imaging mechanism. Next, the light projecting means for irradiating light is switched, and light of a color different from the predetermined color is emitted from the light projecting means toward the electronic component passing through the imaging region, and by the imaging mechanism. The surface of the electronic component is imaged.

  When at least two images of the electronic component (each image captured for each color of light irradiated on the electronic component) are obtained in this way, the determination processing unit performs electronic processing based on each image. The quality of the appearance of the part is determined.

  As described above, according to the visual inspection apparatus according to the present invention, at least two colors of light are emitted from the illumination device to the electronic component, and the surface of the electronic component is imaged for each color, and the image obtained for each color. As described above, it is a defective portion that cannot be distinguished by light of one color by irradiating at least two colors of light toward the electronic component as described above. Moreover, since it can be made to stand out by irradiating the light of the other color, a more accurate external appearance inspection can be implemented.

  In addition, for example, when the lighting device can irradiate only one color of light, in order to acquire a captured image of the surface of the electronic component by changing the color of the light irradiated to the electronic component, the electronic component is transported. It is necessary to provide a plurality of inspection regions in the direction and to arrange the illumination device and the imaging mechanism in each inspection region. However, in the present invention, since one illumination device can irradiate light of at least two colors, The number of areas may be one, and this can reduce the number of the illuminating devices and the imaging mechanisms, thereby reducing the cost.

  As described above, according to the illuminating device of the present invention, it is possible to make the defective portion stand out more reliably by irradiating the electronic component with light of at least two colors. In addition, according to the appearance inspection apparatus according to the present invention, it is possible to accurately inspect the appearance of the electronic component by irradiating at least two colors of light toward the electronic component and more reliably highlighting the defective portion. In addition, since the lighting device can irradiate light of at least two colors, the number of the lighting devices and the imaging mechanism can be reduced and the cost can be reduced.

  Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. 1 is a front view showing a partial schematic configuration of a part of the appearance inspection apparatus according to the embodiment of the present invention, and FIG. 2 is a plan view of the appearance inspection apparatus shown in FIG. It is.

  As shown in FIGS. 1 and 2, the appearance inspection apparatus 1 of this example includes, for example, a supply unit (not shown) that supplies a multilayer capacitor C such as a multilayer ceramic chip capacitor, and a supply unit (not shown). A transport unit 10 that transports the supplied multilayer capacitor C in a predetermined transport direction (the direction indicated by an arrow in FIG. 1), an illumination unit 20 that illuminates the multilayer capacitor C transported by the transport unit 10, and illumination by the illumination unit 20 An imaging unit 11 that captures the multilayer capacitor C that has been captured, a determination processing unit 13 that determines whether the appearance of the multilayer capacitor C is acceptable based on an image of the multilayer capacitor C captured by the imaging unit 11, and a determination processing unit 13 , A defective product collecting unit (not shown) for collecting the defective multilayer capacitor C and a good product collecting unit (not shown) for collecting the non-defective multilayer capacitor C. , The illumination unit 20, and a control unit 12 for controlling the operation of the imaging unit 11 and a defective article collecting unit (not shown). In this example, the multilayer capacitor C is described as an example of an electronic component that is an inspection symmetrical object, but the inspection symmetrical object is not limited to this, and a chip-type light emitting diode, a chip-type inductor, etc. You may make it test | inspect the electronic component provided with the dielectric material and the internal electrode.

  The transport unit 10 includes a transparent transport belt 10a, a drive mechanism (not shown) that rotates the transport belt 10a, and the like, and the transport belt from the supply unit (not shown) on the upstream side in the transport direction. The multilayer capacitor C supplied to the upper surface of 10a is transported at a constant speed toward the downstream side in the transport direction.

  The illumination unit 20 is disposed above the transport belt 10a, and is disposed below the transport belt 10a and a first illumination device 21 that illuminates the surface (upper surface) of the multilayer capacitor C transported by the transport belt 10a. And a second illumination device (not shown) for illuminating the back surface (lower surface) of the multilayer capacitor C conveyed by the conveyance belt 10a. The first lighting device 21 is provided on the upstream side in the transport direction from the second lighting device (not shown).

  The first lighting device 21 includes a plurality of light emitting diodes 22a, 23a, and 24a that irradiate light toward the multilayer capacitor C, and each of the light emitting diodes 22a, 23a, and 24a is annularly arranged in a horizontal plane. The first light projecting mechanism 22, the second light projecting mechanism 23, and the third light projecting mechanism 24, and the support member 25 that supports the first light projecting mechanism 22, the second light projecting mechanism 23, and the third light projecting mechanism 24. It is comprised and irradiates light toward the multilayer capacitor C below.

  The first light projecting mechanism 22, the second light projecting mechanism 23, and the third light projecting mechanism 24 are disposed such that the annular arrangement center axes of the light emitting diodes 22a, 23a, and 24a are orthogonal to the horizontal plane and are coaxial with each other. In addition, the first light projecting mechanism 22 is disposed in the upper stage, the second light projecting mechanism 23 is disposed in the middle stage, and the third light projecting mechanism 24 is disposed in the lower stage.

The first light projecting system 22, together with the light emitting diode 22a is irradiated with blue light in the multilayer capacitor C, the inclination angle theta ₁ with respect to the annular arrangement the central axis of the irradiation optical axis of each of the light emitting diode 22a is It is set to 15 ° to 35 ° (55 ° to 75 ° with respect to the surface of the multilayer capacitor C).

The second light projecting system 23, together with the light emitting diode 23a is irradiated with red light in the multilayer capacitor C, the inclination angle theta ₂ with respect to the annular arrangement the central axis of the irradiation optical axis of each of the light emitting diode 23a is It is set to 40 ° to 50 ° (40 ° to 50 ° with respect to the surface of the multilayer capacitor C).

The third light emitting mechanism 24, together with their respective light emitting diodes 24a are irradiated with red light in the multilayer capacitor C, the inclination angle theta ₃ relative to the annular arrangement the central axis of the irradiation optical axis of each of the light emitting diode 24a is It is set to 55 ° to 75 ° (15 ° to 35 ° with respect to the surface of the multilayer capacitor C).

  The light emitting diodes 22a, 23a, 24a of the light projecting mechanisms 22, 23, 24 have intersections between the irradiation optical axis and the center axis of the annular arrangement, and tip portions of the light emitting diodes 22a, 23a, 24a. Are arranged so that the distance between them becomes equal.

  The support member 25 is formed of a cylindrical member having an opening up and down, a lower opening 25a having a larger diameter than the upper opening 25b, and the upper opening 25b being conveyed by the conveying belt 10a. The light emitting diodes 22a, 23a, and 24a of the light projecting mechanisms 22, 23, and 24 are arranged on the inner peripheral surface of the light emitting diodes 22a, 23a, and 24a on the inner peripheral surface thereof. It accommodates so that the axis line of 25a and the upper opening part 25b may become coaxial.

  The second illumination device (not shown) has a configuration in which the first illumination device 21 is provided upside down, and irradiates light toward the upper multilayer capacitor C. Therefore, the detailed description is abbreviate | omitted.

In this way, the blue light is irradiated onto the multilayer capacitor C because the defective portion existing on the surface of the multilayer capacitor C such as cracks and scratches when the blue light is irradiated onto the multilayer capacitor C. It is because it is easy to make it stand out. Further, the irradiation optical axis of the light emitting diodes 22a, are we inclined angle theta ₁ to 15 ° to 35 ° with respect to the annular arrangement central axis, as long as it is within this range, the defect existing on the surface of the multilayer capacitor C It is because it can make it stand out more effectively.

Also, the red light is applied to the multilayer capacitor C because when the red light is applied to the multilayer capacitor C, the multilayer dielectric C and the internal electrode are lifted up. This is because it is easy to make the defective part to stand out. Further, the irradiation optical axis of the light emitting diode 23a, the inclination angle theta ₂ to 40 ° to 50 ° with respect to the annular arrangement central axis of the irradiation optical axis of the light emitting diode 24a, the inclination angle theta ₃ relative to the annular arrangement center axis 55 The reason why the angle is in the range of 75 ° to 75 ° is that if it is within this range, the defective portion existing inside the multilayer capacitor C can be more effectively highlighted. Further, by reducing the angle between the irradiation optical axis and the surface of the multilayer capacitor C, it becomes easier to detect a shape defect of the multilayer capacitor C such as a chip. The reason why the two light projection mechanisms 23 and 24 for irradiating red light are provided is to increase the amount of light radiated to the surface of the multilayer capacitor C.

  The imaging unit 11 includes a first CCD camera 11 a disposed above the first illumination device 21 and a second CCD camera (not illustrated) disposed below the second illumination device (not illustrated). Become. The first CCD camera 11a is arranged so that the imaging optical axis thereof is coaxial with the annular arrangement center axis and the axes of the lower opening 25a and the upper opening 25b of the support member 25, and is conveyed by the conveyance belt 10a and is predetermined. The surface of the multilayer capacitor C passing through the imaging region is imaged through the upper opening 25b, the internal space, and the lower opening 25a of the support member 25.

  The second CCD camera (not shown) has a configuration in which the first CCD camera 11a is provided upside down, and images the back surface of the multilayer capacitor C that is transported by the transport belt 10a and passes through a predetermined imaging region.

  The controller 12 controls the light projecting mechanisms 22, 23, 24 of the first illumination device 21 to control the lighting state of the light emitting diodes 22a, 23a, 24a, and passes through the imaging area of the first CCD camera 11a. While irradiating light toward the multilayer capacitor C therein, the imaging timing of the first CCD camera 11a is controlled to image the surface of the multilayer capacitor C irradiated with light from the respective light emitting diodes 22a, 23a, and 24a.

  Specifically, a predetermined time after the multilayer capacitor C conveyed by the conveyor belt 10a is detected by the light emitting / receiving sensor 14 (after the multilayer capacitor C passes the detection area of the sensor 14, the first CCD camera 11a takes an image. After the elapse of time until it is conveyed to a predetermined position in the area, first, each light emitting diode 22a of the first light projecting mechanism 22 is turned on to direct blue light to the multilayer capacitor C as shown in FIG. The surface of the multilayer capacitor C is imaged by the first CCD camera 11a.

  Thereafter, the light emitting diodes 22a of the first light projecting mechanism 22 are turned off, the light emitting diodes 23a and 24a of the second light projecting mechanism 23 and the third light projecting mechanism 24 are turned on, and red light is applied to the multilayer capacitor C. Then, the surface of the multilayer capacitor C is imaged by the first CCD camera 11a, and the light emitting diodes 23a and 24a of the second light projecting mechanism 23 and the third light projecting mechanism 24 are turned off. In this way, the multilayer capacitor C conveyed at a constant speed by the conveyor belt 10a is irradiated with blue light and irradiated with red light while passing through the imaging area of the first CCD camera 11a. The surface is imaged.

  The control unit 12 controls the second illumination device (not shown) and the second CCD camera (not shown) in the same manner as the first illumination device 21 and the first CCD camera 11a. Specifically, a predetermined time after the multilayer capacitor C is detected by the light emitting / receiving sensor 14 (after the multilayer capacitor C has passed the detection region of the sensor 14, within the imaging region of the second CCD camera (not shown)). After a lapse of time until it is transported to a predetermined position, the second illumination device (not shown) emits blue light and the back surface of the multilayer capacitor C is imaged by a second CCD camera (not shown). The second illumination device (not shown) emits red light and the back surface of the multilayer capacitor C is imaged by a second CCD camera (not shown).

  The determination processing unit 13 includes images of the surface of the multilayer capacitor C captured by the first CCD camera 11a (an image when the blue light is irradiated and an image when the red light is irradiated), Analyzing each image (image when irradiated with blue light and image when irradiated with red light) on the back surface of the multilayer capacitor C imaged by a second CCD camera (not shown). Pass or fail.

  Specifically, a defect portion K existing on the front surface or the back surface of the multilayer capacitor C such as a crack or a scratch is detected from an image captured when blue light is irradiated (see FIG. 4), and the red color is detected. A multilayer capacitor C such as a defective portion K (see FIG. 5) existing in the multilayer capacitor C, such as floating of the laminated dielectric and internal electrodes, or a chipping from an image captured when light is irradiated. Detect shape defects. When a defect is detected, a defective product collection signal is transmitted to the control unit 12.

  The defective product collection unit (not shown) includes a suction nozzle (not shown) provided on the conveyance belt 10a on the downstream side in the conveyance direction with respect to the illumination unit 20 and the imaging unit 11, and a determination process. The defective product collection signal transmitted from the unit 13 is received by the control unit 12, and the multilayer capacitor C in which the front surface is imaged by the first CCD camera 11 a and the back surface by the second CCD camera (not shown) is received for a predetermined time from the reception. After a lapse of a time until a suction nozzle (not shown) reaches a suction area, the nozzle is actuated. By this operation, the defective multilayer capacitor C is sucked and collected from the suction nozzle (not shown).

  The non-defective product recovery unit (not shown) is a non-defective product recovery box disposed below the downstream end of the transport belt 10a in the transport direction, and is discharged from the end of the transport belt 10a on the downstream end side in the transport direction and dropped. Collect the multilayer capacitor C as a good product.

  According to the appearance inspection apparatus 1 of the present example configured as described above, the multilayer capacitor C is supplied from the supply unit (not shown) onto the transport belt 10a, and the supplied multilayer capacitor C is in a predetermined transport direction. It is conveyed to.

  In the middle of the conveyance, the multilayer capacitor C when the blue light and the red light are emitted from the first illumination device 21 by the first CCD camera 11a under the control of the control unit 12 is used. The multilayer capacitor when the surface of the image sensor is imaged and when the second CCD camera (not shown) emits the blue light and the red light from the second illumination device (not shown) The back side of C is imaged.

  Thereafter, the determination processing unit 13 determines whether the appearance of the multilayer capacitor C is good or bad based on the images of the front and back surfaces of the multilayer capacitor C taken by the first CCD camera 11a and the second CCD camera (not shown). If it is determined as defective, under the control of the control unit 12, the defective multilayer capacitor C is sucked and collected from the suction nozzle (not shown) to the defective product collecting unit (not shown). If determined, the product is collected by a non-defective product collection unit (not shown).

  Thus, according to the appearance inspection apparatus 1 of this example, the multilayer capacitor C is irradiated with blue and red light from the first illumination device 21 and the second illumination device (not shown), and the multilayer capacitor is associated with each color. The front and back surfaces of C are imaged, and pass / fail judgment is performed based on the images obtained for each color. As described above, by irradiating the multilayer capacitor C with blue and red light, Even a defective portion that cannot be highlighted by colored light can be highlighted by irradiating the light of the other color (blue light is the surface of the multilayer capacitor C such as cracks and scratches). And the red light can stand out the defective portion existing inside the multilayer capacitor C, such as the floating of the laminated dielectric and the internal electrode. Et al), can be performed with higher precision appearance inspection.

Further, by setting the inclination angle theta ₁ of the irradiation optical axis of the light emitting diode 22a for irradiating blue light with 15 ° to 35 °, it is possible to more effectively accentuate the defective portions on the surface of the multilayer capacitor C In addition, the inclination angles θ ₂ and θ ₃ of the irradiation optical axes of the light emitting diodes 23a and 24a that emit red light are set to 40 ° to 50 ° and 55 ° to 75 °, respectively, so that the inside of the multilayer capacitor C can be obtained. The existing defective portion can be more effectively highlighted, and the angle between the irradiation optical axis of the light emitting diodes 23a and 24a and the surface of the multilayer capacitor C can be reduced to reduce chipping such as chipping. The shape defect can be easily detected, and furthermore, by providing two light projecting mechanisms 23 and 24 for irradiating red light, the amount of light irradiated to the multilayer capacitor C can be increased. Therefore, the appearance can be inspected with higher accuracy than these.

  Further, for example, if the first lighting device 21 and the second lighting device (not shown) can irradiate only one color of light, the color of the light irradiating the multilayer capacitor C is changed to change the multilayer capacitor C. In order to obtain captured images of the front and back surfaces of the substrate, it is necessary to provide a plurality of inspection areas in the transport direction of the multilayer capacitor C and to arrange an illumination device and a CCD camera in each inspection area. Since one first lighting device 21 and two second lighting devices (not shown) can radiate blue and red light, only one inspection area is required, which allows the number of lighting devices and CCD cameras to be provided. This can reduce the cost.

  As mentioned above, although one Embodiment of this invention was described, the specific aspect which this invention can take is not limited to this at all.

  In the above example, the light emitting diodes 22a, 23a, and 24a of the light projecting mechanisms 22, 23, and 24 are formed by intersecting the irradiation optical axis with the annular arrangement center axis and the tips of the light emitting diodes 22a, 23a, and 24a. However, the present invention is not limited to this, and as shown in FIG. 6, the light emitting diodes 22a, 23a, and 24a are arranged so that their annular arrangement diameters are equal. You can also

  In the above example, the first lighting device 21 and the second lighting device (not shown) are configured to emit blue and red light. However, the present invention is not limited to this, and in addition to blue and red light. Further, it is possible to irradiate light of different colors, or to irradiate light of at least two colors different from blue and red.

  Furthermore, in the above example, the configuration is such that the front and back surfaces of the multilayer capacitor C are inspected, but the inspection surface is not limited to the front and back surfaces.

  In the above example, the transport unit 10 is configured by a transport belt 10a and the like, and the multilayer capacitor C is transported by the transport belt 10a. However, the transport unit 10 is configured by a transparent glass turntable or the like. The multilayer capacitor C may be transported by this turntable.

  In the above example, the red light is emitted from both the second light projecting mechanism 23 and the third light projecting mechanism 24 toward the multilayer capacitor C. However, the present invention is not limited to this. It is also possible to turn on only the third light projecting mechanism 24 without lighting the second light projecting mechanism 23 at the time of light irradiation. For example, when inspecting a black inspection object, both the second light projection mechanism 23 and the third light projection mechanism 24 are turned on. When inspecting a white inspection object, only the third light projection mechanism 24 is used. If the amount of light irradiated toward the inspection object is adjusted by controlling whether or not to turn on the second light projecting mechanism 23 in accordance with the characteristics of the inspection object, It becomes possible to inspect with accuracy. As described above, it is not necessary to turn on (use) all of the first light projecting mechanism 22, the second light projecting mechanism 23, and the third light projecting mechanism 24, and the light projecting mechanism that lights the light according to the characteristics of the inspection object. 22, 23, and 24 may be set as appropriate.

  In the above example, each of the light projecting mechanisms 22, 23, and 24 is composed of the light emitting diodes 22a, 23a, and 24a. However, the present invention is not limited to this, and the light source and one end side are arranged at a predetermined interval from the light source. The other end side can also be constituted by an optical fiber or the like in which the other end is branched into a plurality and each end is arranged in a ring shape (radially). In this case, blue light and red light from the light source enter from one end side of the optical fiber, are transmitted to the other end side of the optical fiber, and are irradiated toward the multilayer capacitor C from the other end side. The

It is the front view which showed the one part schematic structure of the external appearance inspection apparatus which concerns on one Embodiment of this invention in the partial cross section. It is a top view of the external appearance inspection apparatus shown in FIG. It is a timing chart which showed the control state of an illuminating device and a CCD camera concerning this embodiment. It is explanatory drawing which showed the defect example of the multilayer capacitor. It is explanatory drawing which showed the defect example of the multilayer capacitor. It is sectional drawing which showed schematic structure of the illuminating device which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Appearance inspection apparatus 10 Conveyance part 10a Conveyor belt 11 Imaging part 11a 1st CCD camera 12 Control part 13 Judgment processing part 14 Light emission light reception type sensor 20 Illumination part 21 1st illumination device 22 1st light projection mechanism 22a Light emitting diode 23 2nd light projection Optical mechanism 23a Light emitting diode 24 Third light projecting mechanism 24a Light emitting diode 25 Support member C Multilayer capacitor

Claims (4)

Provided in an appearance inspection apparatus that images an electronic component and inspects its appearance, and an illumination device that illuminates the electronic component during imaging,
It has a plurality of light projecting units that irradiate light toward the electronic component, and includes a plurality of light projecting means in which each light projecting unit is arranged in an annular shape,
Each of the light projecting means is disposed coaxially and arranged in the axial direction, and at least one of the light projecting means emits light of a color different from that of the other light projecting means. The illumination device is configured to irradiate the electronic component from a portion.   Each of the light projecting units includes a light projecting unit that emits blue light from the light projecting unit toward the electronic component, and a light projecting unit that emits red light from the light projecting unit toward the electronic component. The lighting device according to claim 1, further comprising at least light means. Each of the light projecting means comprises a first light projecting means, a second light projecting means and a third light projecting means arranged in parallel in the axial direction.
The first light projecting unit is arranged so that an irradiation optical axis of the light projecting unit is inclined by 15 ° to 35 ° with respect to an axis thereof, and configured to irradiate blue light toward the electronic component. And
The second light projecting unit is arranged so that an irradiation optical axis of the light projecting unit is inclined by 40 ° to 50 ° with respect to an axis thereof, and configured to irradiate red light toward the electronic component. And
The third light projecting means is arranged so that an irradiation optical axis of the light projecting unit is inclined by 55 ° to 75 ° with respect to an axis thereof, and is configured to irradiate red light toward the electronic component. The lighting device according to claim 2, wherein An appearance inspection apparatus for imaging an electronic component and inspecting its appearance,
A transport mechanism for transporting the electronic component in a predetermined transport direction;
An imaging mechanism that images the surface of the electronic component that is transported by the transport mechanism and passes through the imaging region;
The illumination device according to any one of claims 1 to 3, which illuminates an electronic component conveyed in the imaging region by the conveyance mechanism;
A determination processing unit that determines the quality of the appearance of the electronic component based on the image of the electronic component imaged by the imaging mechanism;
A control unit for controlling the operation of the illumination device and the imaging mechanism,
The imaging mechanism is arranged such that its imaging optical axis is located within the arrangement ring of the light projecting portion of each of the light projecting means,
The control unit controls each light projecting unit to irradiate light from the light projecting unit that emits light of the same color among the light projecting units toward the electronic component. While passing through the imaging area, the light projecting means for irradiating light is switched to change the color of light irradiated to the electronic component, and the imaging mechanism is controlled to It is configured to image the surface of the electronic component for each color of irradiated light,
The appearance inspection apparatus, wherein the determination processing unit is configured to perform pass / fail determination based on each image captured for each color of light irradiated on the electronic component.

Images