JPH116718A - Solder defect inspecting instrument for printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent incorrect detection, by a method wherein an illumination is made in the direction crossing the longitudinal direction of a soldered part of each pin of parts mounted on the surface of a printed circuit board, to take an image of the soldered part of each pin with a camera above the substrate while no light is illuminated to a flux part other than a poorly soldered part of the pin. SOLUTION: First and second lighting devices 11 and 12 are arranged separately askew above in the direction orthogonal to the longitudinal direction of a soldered part 32 of each pin 31 of parts mounted on the surface of a printed circuit board 3. Light is made to irradiate four belt-shaped areas in the direction almost orthogonal to the longitudinal direction of the soldered part 32, respectively. No light is directly illuminated to the flux part equivalent to a recess between the poorly soldered parts 32 of adjacent pins 31. In other words, the angles of inclination of the first and the second lighting devices 11 and 12 are adjusted to an angle that keeps light from directly illuminating the flux part. An arithmetic controller 5 judges a solder defect from the brightness of the image of the soldered part 32 of each pin 31 based on an image data of a camera 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount component having a large number of pins mounted on a printed circuit board. An image of a soldered portion of each pin of the surface mounted component illuminated by the camera disposed above the printed circuit board is captured, and based on image data output from the camera, the arithmetic and control unit The present invention relates to a printed circuit board soldering defect inspection apparatus in which a bright spot of a defective soldering portion is detected based on the brightness of an image of a soldered portion of each pin of the surface mount component, and a defective soldering is determined.

[0002]

2. Description of the Related Art Conventional first printed circuit board soldering defect inspection apparatus (Japanese Patent Laid-Open No. Hei 3-162611, Japanese Patent Laid-Open No. 7-6596).
8) is parallel to the longitudinal direction of the soldered portion of the pins P in a range covering all the pins P protruding from one side wall of the printed board K as the inspection target component as shown in FIG. Light is emitted from a light source L obliquely from above in a certain direction, and a camera C disposed above the printed board K
An image of the soldering portion H of each pin P of the surface-mounted component illuminated by the illumination is captured, and a defective solder is determined from the captured image of the soldering portion H of each pin P. .

As shown in FIG. 4, a conventional second printed board soldering defect inspection apparatus (Japanese Patent Application Laid-Open No. 1-260686) has a longitudinal direction of a soldered portion H of each pin P of a printed board K which is a component to be inspected. In the direction parallel to the longitudinal direction of the soldering portion H of each pin P, light is applied from obliquely above, and the soldering portion of the pin P An image of the soldering portion H of each pin P of the surface mount component illuminated by the camera C disposed in the longitudinal direction of the pin H is captured. The mounting failure was determined.

A third conventional printed circuit board soldering defect inspection apparatus uses a circular illumination to cover a range including all the soldered portions of each pin on each side wall surface of the printed circuit board with the same illumination. Irradiation was performed at the same time, an image of the soldered portion of each pin on each side wall surface was captured, and a soldering failure was determined from the captured image of the soldered portion of each pin.

[0005]

As shown in FIG. 3, the conventional first printed circuit board soldering defect inspection apparatus includes all pins P projecting from one side wall of the printed circuit board K. As shown in FIG.
Is irradiated from obliquely above in a direction parallel to the longitudinal direction of the soldering portion H of the pin P in a range that covers the pin P. Therefore, the light is also applied to the flux portion other than the defective solder portion of the pin P. In addition, there is a problem that a bright spot generated in a flux portion is erroneously detected.

In the first conventional printed circuit board soldering defect inspection apparatus, bright spots having the same brightness are generated in the soldering defective portion of the pin P and the other flux portions, so that the S / N is poor and There is a problem that four illuminations are required to detect defective solder portions of the pins P projecting from the four side walls of the printed board K.

[0007] As shown in FIG. 4, the conventional second printed board soldering defect inspection apparatus uses all the pins in a direction intersecting the longitudinal direction of the soldering portion H of each pin P of the printed board K. Light is radiated from obliquely above to a sufficiently wide rectangular area covering P, and the camera C disposed obliquely upward outside in a direction parallel to the longitudinal direction of the soldering portion H of each of the pins P. Since the image of the soldered portion H of each of the pins P irradiated by the illumination is captured, in order to detect defective solder portions of the pins P projecting from the four side walls of the printed board K, respectively. However, there is a problem in that four sets of lighting and a camera are required, which is expensive.

The third conventional printed circuit board soldering defect inspection apparatus uses a circular illumination to illuminate a wide area including all the measurement points of the soldered portions of the pins on each side wall surface of the printed circuit board with the same illumination. Irradiated at the same time, an image of the soldered portion of each pin on each side wall surface is captured, and from the captured image of the soldered portion of each pin, a soldering failure is determined. Since the illumination is illuminated from all directions, light is also applied to a flux portion other than the solder defective portion of the pin,
There is a problem that a bright spot generated in the flux part is erroneously detected.

In the third conventional printed circuit board soldering defect inspection apparatus, bright spots having the same brightness are generated in the soldering defective portion of the pin and the other flux portion, so that the S / N ratio is high.
There was a problem that was bad.

The inventor of the present invention illuminates a surface mounting component having a large number of pins mounted on a printed circuit board in a direction intersecting a longitudinal direction of a soldering portion of each pin,
An image of a soldering portion of each pin of the surface mount component illuminated by a camera disposed above the printed circuit board is captured, and soldering of each pin of the surface mount component is performed based on output image data. Depending on the brightness of the image of the attachment part,
The first technical idea of the present invention is that the defective soldering is determined by detecting the bright spot of the defective soldering portion.

Further, the inventor of the present invention disposes the illuminating device on the side wall surfaces on both sides of each orthogonal side wall surface having a number of pins mounted on the four side wall surfaces of the rectangular printed circuit board. The first and second illuminating devices arranged obliquely upward in a direction orthogonal to the direction orthogonal to the longitudinal direction of the soldered portion of each pin so as to irradiate the illumination, Four pins for each pin of a surface mount component disposed on each side wall surface of the printed circuit board illuminated by the illumination of the first and second lighting devices by the camera disposed directly above the printed circuit board. An image of the soldering portion in the band-shaped area is taken, and the arithmetic and control unit is used to pick up an image of the surface mount component 4 disposed on each side wall surface of the printed circuit board based on the image data output from the camera.
The second technical idea of the present invention is that the soldering failure of the entire printed circuit board is determined based on the brightness of the image of the soldering portion of each pin in each strip-shaped region.

Further, as a result of repeated research and development, the present inventor does not irradiate light to a flux portion other than the defective solder portion of the pin, thereby preventing erroneous detection of a luminescent spot generated in the flux portion, Of bright spots of the same brightness in the solder defective part of the solder and the other flux parts
Thus, the present invention has been achieved which prevents the deterioration of / N and minimizes the number of illuminations and cameras and achieves the objective of enabling cost reduction.

[0013]

According to a first aspect of the present invention, there is provided a printed board soldering defect inspection apparatus comprising: a plurality of pins of a surface mount component having a large number of pins mounted on the printed board; An illumination device that irradiates illumination in a direction intersecting with the longitudinal direction of the soldering portion, and an image of the soldering portion of each pin of the surface mounted component that is disposed above the printed circuit board and is illuminated and illuminated. The camera comprises a camera for imaging, and an arithmetic and control unit for judging a soldering failure based on the brightness of an image of a soldered portion of each pin of the surface mount component based on image data output from the camera.

According to a second aspect of the present invention, there is provided the printed circuit board soldering defect inspection apparatus according to the first aspect, wherein the lighting device is arranged such that the illumination device is arranged such that the pins of the surface mount component are soldered in the longitudinal direction. Is configured to irradiate illumination in a direction orthogonal to or close to the direction.

According to a third aspect of the present invention, there is provided the printed circuit board soldering defect inspection apparatus according to the second aspect, wherein the lighting device is configured such that the illuminating device has four surfaces of the printed circuit board formed of a rectangular main body. It has a large number of pins mounted on the side wall surfaces, and irradiates the illumination in a direction almost orthogonal to the longitudinal direction of the soldered portion of each pin disposed on both side wall surfaces of each orthogonal side wall surface. The first and second illumination devices are respectively arranged obliquely upward in a direction orthogonal to.

According to a fourth aspect of the present invention, there is provided a printed circuit board soldering defect inspection apparatus according to the third aspect, wherein the camera is disposed right above the printed board, and It is configured to capture an image of a soldered portion in each of the four band-shaped regions of each pin of the surface mount component disposed on each side wall surface of the printed circuit board illuminated by the second illumination device. Is what it is.

According to a fifth aspect of the present invention, there is provided the printed board soldering defect inspection apparatus according to the fourth aspect, wherein the arithmetic and control unit is configured to execute the printing based on image data output from the camera. The soldering failure is determined based on the brightness of the image of the soldered portion of each pin in the four strip-shaped regions of the surface mount component disposed on each side wall surface of the substrate.

(Effect of the Invention) In the printed circuit board soldering defect inspection apparatus according to the first invention having the above-described structure, the illumination device includes:
The camera disposed above the printed circuit board, irradiating illumination in a direction intersecting the longitudinal direction of the soldering portion of each pin of the surface mount component having a large number of pins mounted on the printed circuit board, and disposed above the printed circuit board However, based on image data output from the camera, the arithmetic and control unit captures an image of a soldered portion of each pin of the surface mounted component irradiated with illumination,
The soldering failure is determined based on the brightness of the image of the soldered portion of each pin of the surface mount component.

In the printed board soldering defect inspection apparatus according to the second invention having the above-mentioned structure, in the first invention, the illumination device may be such that the lighting device is perpendicular to or longitudinal to a longitudinal direction of a soldering portion of each pin of the surface mount component. It irradiates illumination in a near direction.

The printed circuit board soldering defect inspection apparatus according to the third aspect of the present invention, which is arranged as described above in the second aspect, is disposed obliquely upward in a direction orthogonal to a longitudinal direction of a soldering portion of each of the pins of the surface mount component. Surface mounting, wherein the first and second illuminating devices constituting the illuminating device are provided with a plurality of pins respectively mounted on two side walls of the printed circuit board formed by a rectangular main body. The illumination is radiated in a direction substantially orthogonal to the longitudinal direction of the soldering portion of each pin disposed on both side wall surfaces of each of the orthogonal side wall surfaces of the component.

According to a fourth aspect of the present invention, there is provided a printed circuit board soldering defect inspection apparatus according to the third aspect, wherein the camera disposed right above the printed board is provided by the first and second lighting devices. An image of a soldered portion of each pin of a surface mount component in two strip-shaped regions arranged on the opposite side wall surface of the printed circuit board to which the illumination is applied is taken.

According to a fifth aspect of the present invention, there is provided the printed board soldering defect inspection apparatus according to the fourth aspect, wherein the arithmetic and control unit is arranged on each side wall surface of the printed board based on image data output from the camera. The soldering failure is determined based on the brightness of the image of the soldering portion of each pin in the four strip-shaped regions of the arranged surface mount component.

[0023]

According to the first aspect of the present invention, there is provided a printed circuit board soldering defect inspection apparatus, wherein the illumination device is arranged so that the lighting device intersects the longitudinal direction of the soldering portion of each pin of the surface mount component of the printed circuit board. Irradiates the illumination, and the camera disposed above the printed circuit board captures an image of the soldering portion of each pin of the surface mounted component irradiated by the illumination, so that the flux other than the defective solder portion of the pin is Since no light is applied to the portion, erroneous detection of a bright spot generated in the flux portion is prevented, and bright spots having the same brightness are generated in the solder defective portion of the pin and other flux portions.
/ N is prevented from deteriorating.

The printed circuit board soldering defect inspection apparatus according to a second aspect of the present invention having the above-mentioned action is characterized in that, in the first aspect, the illuminating device is perpendicular to or longitudinal to a longitudinal direction of a soldered portion of each pin of the surface mount component. Since the illumination is applied in the near direction, the flux portion other than the solder defective portion of the pin is not irradiated with the light, so that erroneous detection of the bright spot generated in the flux portion is prevented, and the solder defective portion of the pin and other This has the effect of preventing the deterioration of S / N due to the occurrence of bright spots of the same brightness in the flux portion of the present invention.

The printed board soldering defect inspection apparatus according to a third aspect of the present invention, which has the above-described operation, is characterized in that, in the second aspect, the illumination is arranged in a direction orthogonal to a longitudinal direction of a soldering portion of each of the pins of the surface-mounted component. The first and second illuminating devices constituting the device are provided on a side wall surface on both sides of each orthogonal side wall surface with a large number of pins respectively mounted on four side wall surfaces of the printed circuit board. Since the illumination is radiated in a direction substantially orthogonal to the longitudinal direction of the soldered portion of each pin, the flux portion other than the solder defective portion of the pin is not irradiated with the light, so that the luminescent spot generated in the flux portion is not mistaken. This has the effect of preventing detection and preventing the deterioration of S / N due to the occurrence of bright spots of the same brightness in the defective solder portions of the pins and other flux portions.

The printed circuit board soldering defect inspection apparatus according to a fourth aspect of the present invention, which has the above-described operation, is characterized in that, in the third aspect, the camera disposed right above the printed circuit board is controlled by the first and second lighting devices. The effect that it is possible to capture the images of the soldering portions in the two band-shaped regions of each pin of the surface mount component disposed on each side wall surface of the printed circuit board respectively illuminated at a time. To play.

According to a fifth aspect of the present invention, there is provided a printed circuit board soldering defect inspection apparatus according to the fourth aspect, wherein the arithmetic and control unit is arranged on each side wall surface of the printed board based on image data output from the camera. Since the brightness of the image of the soldering portion of each pin in the four strip-shaped regions of the surface mounted component arranged is used to determine the poor soldering of all the soldering portions, the illumination and the camera are minimized. This has the effect of enabling cost reduction.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are described below.
This will be described with reference to the drawings.

(Embodiment) As shown in FIGS. 1 and 2, the printed board soldering defect inspection apparatus according to the present embodiment has a plurality of pins 31 of a surface mount component having a large number of pins 31 mounted on a printed board 3. Two illumination devices 1 for irradiating illumination in a direction intersecting the longitudinal direction of the soldering portion 31
1, 2 and a camera 2 arranged above the printed circuit board 3 for picking up an image of a soldered portion of each pin of the illuminated surface mount component, and an image connected to and output from the camera 2 An arithmetic and control unit 5 for determining a soldering failure based on the brightness of the image of the soldering portion 32 of each pin 31 of the printed circuit board 3 of the surface mount component based on the data.

As shown in FIGS. 1 and 2, the printed circuit board 3 has a rectangular main body, a horizontal portion 311 at one end protruding from four side walls, and a soldering portion via a vertical portion 312. A large number of substantially crank-shaped pins 31 including the horizontal portion 313 at the other end of the pin 32 are provided, that is, six pins are juxtaposed in the present embodiment.

As shown in FIGS. 1 and 2, the illuminating devices 11 and 12 illuminate in a direction orthogonal to or close to the longitudinal direction of the soldering portion 32 of each pin 31 of the printed board 3 of the component to be inspected. It is arranged to irradiate.

The illuminating device comprises a plurality of pins 31 of surface mount components mounted on the four side walls of the printed circuit board 3 each formed of a rectangular main body. Each pin 31 arranged on the side wall surface
In order to illuminate the soldering portions in the four band-shaped regions 41 to 44 including all the pins in a direction substantially perpendicular to the longitudinal direction of the soldering portion 32, The first and second lighting devices 11 and 12 are arranged.

The camera 2 is disposed directly above the center of the printed circuit board 3 as shown in FIGS.
Four strip-shaped areas 41 to 4 of each pin 31 of a surface mount component disposed on each side wall surface of the printed circuit board 3 illuminated by the first and second illumination devices 11 and 12
4 are arranged so as to capture an image of the soldering portion 32.

Based on the image data output from the camera 2 as shown in FIG.
A soldering failure is determined based on the brightness of the image of the soldering portion 32 of each pin 31 in the four belt-shaped regions 41 to 44 of the surface mount component disposed on each side wall surface of the printed board 3. is there.

In the printed board soldering defect inspection apparatus according to the embodiment having the above-mentioned configuration, the illumination device is disposed obliquely upward in a direction orthogonal to a longitudinal direction of a soldering portion of each of the pins of the surface mounted component of the printed board. The first and second illuminating devices 11 and 12 constituting the device are provided with a large number of pins 31 of surface mount components which are respectively mounted on four side walls of the printed circuit board 3 formed by a rectangular main body. The four band-like regions 41 to 41 in the direction substantially orthogonal to the longitudinal direction of the soldering portion 32 of each pin 31 disposed on both side wall surfaces of each of the provided orthogonal side wall surfaces.
44 is illuminated.

That is, the camera 2 disposed right above the printed circuit board 3 is mounted on the side walls on both sides of the printed circuit board 3 illuminated by the first and second lighting devices 11 and 12. Two band-shaped regions 41 provided,
An image of the soldered portion 32 of each pin 31 of the surface mount components 43, 42, and 44 is taken.

At the time of inspection of the two band-shaped areas 41 and 43, the illumination by the first illumination device 11
Each of the band-shaped regions 41 and 43 is illuminated, image data is captured by the camera 2, and a solder defect of the soldering section 32 is determined. The two strips 42
In the inspection of (2) and (4), the illumination by the second illumination device 12 illuminates the two band-shaped regions 42 and 44, the image data is captured by the camera 2, and the soldering failure of the soldering portion 32 is determined. It is.

The illumination is radiated in a direction substantially orthogonal to the longitudinal direction of the soldering portion 32 of each pin 31 disposed on the side wall surface on both sides of each side wall surface. Light is not directly applied to the flux portion corresponding to the concave portion between 32. That is, the inclination angles of the first and second lighting devices 11 and 12 are adjusted to an angle such that the flux portion is not directly irradiated with light.

Based on the image data output from the camera 2, the arithmetic and control unit 5 controls each of the surface-mounted components in the four strip regions 41 to 44 disposed on each side wall surface of the printed circuit board 3. The soldering failure is determined based on the brightness of the image of the soldering portion 32 of the pin 31.

The printed circuit board soldering defect inspection apparatus according to the embodiment having the above-mentioned operation is characterized in that each of the pins 3
The first and second lighting devices 11 and 12 constituting the lighting device arranged in a direction orthogonal to the longitudinal direction of the soldering portion 32 of the first soldering portion 32 are respectively provided on four side wall surfaces of the printed circuit board 3. Each pin 31 provided on the side wall surface on both sides of each orthogonal side wall surface having a large number of mounted pins 31
Since the illumination is radiated in a direction substantially perpendicular to the longitudinal direction of the soldering portion 32, no light is applied to the flux portion other than the solder defective portion 32 of the pin 31. This has the effect of preventing erroneous detection and preventing the deterioration of S / N due to the occurrence of bright spots of the same brightness in the solder defective portions 32 of the pins 31 and the other flux portions. .

That is, the illumination is radiated in a direction almost orthogonal to the longitudinal direction of the soldering portion 32 of each pin 31 disposed on both side wall surfaces of each side wall surface. Since light is not directly applied to the flux portion corresponding to the concave portion between the defective portions 32, erroneous detection of a luminescent spot generated in the flux portion is prevented, and the solder defective portion 32 of the pin 31 and the other flux portions are removed. This prevents the S / N from deteriorating due to the occurrence of bright spots having the same brightness.

Further, in the printed board soldering defect inspection apparatus according to the present embodiment, the camera 2 disposed directly above the printed board 3 includes the first and second lighting devices 11 and 12.
Of the pins 31 of the surface mount components in the two band-shaped regions 41, 43 and 42, 44 arranged on the respective side walls on the opposite side of the printed board 3 illuminated by the There is an effect that it is possible to capture images at one time.

That is, the measurement location is divided into a limited band-like region including the soldering portions 32 of the plurality of pins 31, and illumination is radiated from a predetermined angle obliquely upward from a direction substantially orthogonal to the divided band-like region. A bright spot is generated only at a solder defect of the pin 31 protruding upward, thereby suppressing erroneous detection in the related art.

Further, in the printed board soldering defect inspection apparatus according to the present embodiment, the arithmetic and control unit 5 is arranged so that the arithmetic and control unit 5 is mounted on each side wall of the printed board 3 based on the image data output from the camera 2. Four strips 4 of the part
Since the soldering failure of all the soldering portions 32 is determined based on the brightness of the image of the soldering portion 32 of each pin 31 in 1 to 44, the illumination and the camera are minimized, and the cost can be reduced. This has the effect.

The above-described embodiments have been described by way of example only, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

In the above-described embodiment, as an example, each pin 3 on the side wall of one printed circuit board is used as a part to be inspected.
Although an example of inspecting one soldering portion has been described, the present invention is not limited to such an example. In order to inspect a soldering portion of each pin 31 on a plurality of side walls of a printed circuit board as a component to be inspected, An embodiment in which the illumination and the camera are moved and inspected by an XY robot or the like can be adopted.

[Brief description of the drawings]

FIG. 1 is a front view showing a printed board soldering defect inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a positional relationship between first and second lighting devices according to the embodiment.

FIG. 3 is a front view showing a conventional printed board soldering defect inspection apparatus.

FIG. 4 is a perspective view showing a conventional printed board soldering defect inspection apparatus.

[Explanation of symbols]

 11, 12 Lighting device 2 Camera 3 Flint board 31 Pin 32 Soldering part 5 Arithmetic control device

Claims (5)

[Claims] An illumination device for irradiating illumination in a direction intersecting a longitudinal direction of a soldering portion of each pin of a surface mount component having a large number of pins mounted on a printed circuit board; A camera that is disposed above and captures an image of a soldering portion of each pin of the surface-mounted component to which illumination is applied; and a soldering of each pin of the surface-mounted component based on image data output from the camera. Depending on the brightness of the part image,
A printed board soldering defect inspection device, comprising: an arithmetic and control unit for determining a soldering defect. 2. The illumination device according to claim 1, wherein the illumination device is configured to irradiate illumination in a direction orthogonal to or close to a longitudinal direction of a soldering portion of each pin of the surface mount component. Characteristic printed circuit board solder defect inspection equipment. 3. The illuminating device according to claim 2, wherein the illuminating device includes a plurality of pins respectively mounted on four side walls of the printed circuit board formed by a rectangular main body. The first and second lighting devices are disposed obliquely upward in a direction perpendicular to the direction perpendicular to the longitudinal direction of the soldering portion of each pin disposed on the side wall surface, respectively. A printed circuit board soldering defect inspection device characterized by being constituted. 4. The printed circuit board according to claim 3, wherein the camera is disposed directly above the printed circuit board, and is disposed on each side wall surface of the printed circuit board illuminated by the first and second lighting devices. A printed circuit board soldering defect inspection apparatus configured to capture an image of a soldered portion in each of four strip-shaped regions of each pin of the surface mounted component. 5. The computer-readable storage medium according to claim 4, wherein the arithmetic and control unit determines, based on image data output from the camera, four band-shaped regions of the surface-mounted components disposed on each side wall surface of the printed circuit board. A printed circuit board soldering defect inspection apparatus characterized in that a soldering defect is determined based on the brightness of an image of a soldering portion of each pin.