JPH10261900A - Method for inspecting mounted part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a visual inspection equipment of board for inspecting presence or positional shift of an electronic device mounted on a board accurately and efficiently using a sensor. SOLUTION: The inspection equipment comprises a sensor head section 10 performing measurement by projecting laser light, a refraction body for converting the optical path of laser light, a section for scanning on an electronic device 5, a section for controlling the driving of the scanning section and the refraction body, and a section for determining presence or positional shift of the electronic device 5 by receiving the laser light. Outline of the electronic device 5 can be read out through single scanning, with laser light projected from the sensor head section 10 and the mounting state of the electronic device 5 can be inspected accurately and efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a mounted component used for inspecting the presence / absence, displacement, and the like of an electronic component mounted on a substrate.

[0002]

2. Description of the Related Art A conventional method for inspecting a mounted component will be described with reference to the drawings. FIG. 22 is a perspective view showing a conventional board appearance inspection apparatus using the same inspection method.
1, an X-axis robot 25 for moving the displacement sensor 11, a Y-axis robot 27 arranged orthogonally on the X-axis robot 25, and a parallel for transferring the substrate 4 to be inspected. A pair of arranged conveyor units 30,
A board arrival confirmation sensor 35 for detecting that the conveyed substrate 4 has arrived at the inspection position, a substrate fixing portion 40 for fixing the inspected substrate 4 so as not to be subjected to vibration when inspecting the substrate 4, Is controlled by the control unit 2.

[0005] The displacement sensor 11 is mounted on a Y-axis robot 27 that performs orthogonal operation with an X-axis robot 25, and the position information and the shape information of the electronic component 5 mounted on the board 4 to be inspected stored in the control unit 2. , The displacement sensor 11 scans each electronic component 5 once. A personal computer is used for the control unit 2, and the displacement sensor 1
1, an interface circuit for the X-axis robot 25, the Y-axis robot 27, the conveyor section 30, the board arrival confirmation sensor 35, and the board fixing section 40 is built in, and these are electrically connected by the signal cable 8.

In the conventional board appearance inspection apparatus configured as described above, the displacement sensor 11 is scanned in the X or Y direction in FIG. The displacement sensor 11 can detect the displacement between the inspection board 4 and the electronic component 5 mounted thereon, and the displacement sensor 11 scans the electronic component 5 mounted on the board 4 to be inspected. FIG. 23A shows the trajectory of the irradiated laser beam 13 and FIG. 23B shows the waveform 302 of the displacement detected by the displacement sensor 11 at that time.

Here, the level Ha of large displacement is the level of the substrate 4 to be inspected, and the level Hb of small displacement is the level of the electronic component 5.
The threshold value 301 is set between the level Ha and the level Hb, and by detecting the end points L1 and L2 of the electronic component 5, the mounting state of the electronic component 5 mounted on the board 4 to be inspected is changed. Can be inspected. That is, if the end points L1 and L2 exist, it is determined that there is a component, and if not, it is determined that there is no component. If the positions of the end points L1 and L2 are out of the specification of the mounting position, it is determined that the position is shifted.

[0006]

However, in such a conventional method, since the scanning by the displacement sensor 11 is performed linearly, the electronic component 5 is shifted in the Y direction as shown by a broken line 5a in FIG. When they are mounted or mounted with an inclination as shown by a broken line 5b, the end points L1 and L
2 is detected in exactly the same manner as the state of the solid-line electronic component 5, so that there is a problem that the electronic component 5 cannot be detected even if a mounting failure occurs as indicated by broken lines 5a and 5b.

In order to solve this problem, it is conceivable to scan the displacement sensor 11 once from the X direction to a plurality of times in parallel with the Y direction. However, in this case, the inspection time is greatly increased. There was a problem.

Further, since the displacement sensor 11 uses the triangulation method and the scanning is performed linearly, there is a problem that erroneous detection occurs when scanning an area where electronic components are densely packed. He also had points.

The present invention solves such a conventional problem,
It is an object of the present invention to provide a method for inspecting a mounted component, which has a high accuracy in inspecting a displacement of an electronic component and can perform the inspection efficiently and at a high speed.

[0010]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention relates to a method of mounting electronic components on a printed circuit board by adding information of the mounted electronic components to mounting NC data. Inspection data for inspecting the mounted state of electronic components mounted on the device such as presence / absence, misalignment, floating, etc. is created, and based on the created inspection data, a laser beam is irradiated perpendicularly to the inspection object. In order to sequentially scan the electronic components mounted on the printed circuit board by using a sensor that condenses the reflected light reflected at an angle via a light receiving lens to a photoelectric conversion element, the reflected light is mounted on the printed circuit board. The area including at least one side of the electronic component is irradiated with laser light so that the trajectory of the laser light is scanned while performing a circular motion a predetermined number of times, and the reflected light is reflected by the photoelectric conversion element. Presence and misalignment of the electronic component mounted by the height signal is constant, is obtained by a method of inspecting by comparing float and the test data.

According to the present invention, a mounted component can be inspected accurately, efficiently, and at high speed.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 of the present invention provides a method of mounting electronic components on a printed circuit board by adding information on the mounted electronic components to mounting NC data. Inspection data for inspecting the mounted state of the mounted electronic components, such as presence / absence, positional deviation, floating, etc., is created, and based on the created inspection data, a laser beam is irradiated perpendicularly to the inspection object. In order to sequentially scan the electronic components mounted on the printed circuit board using a sensor that collects the reflected light reflected at an angle to the photoelectric conversion element via a light receiving lens, the electronic components mounted on the printed circuit board are scanned. A region including at least one side of the component is irradiated with laser light so that the trajectory of the laser light is scanned while performing a predetermined number of circular motions, and is measured by the photoelectric conversion element from the reflected light. In this method, the quality is determined by comparing the presence / absence, positional deviation, floating, and the like of the mounted electronic component with the inspection data, which has the effect that a high-precision inspection can be performed in one scan. Have.

According to a second aspect of the present invention, in the first aspect of the present invention, the sensor is held in a sensor head portion movable at a variable speed in the horizontal direction, and the length of one side of each electronic component to be inspected is set to one side. By setting the moving speed of the sensor head in accordance with the size of the electronic component to be inspected, regardless of the size of the electronic component to be inspected, the rotational speed of the circular motion of the trajectory of the laser beam scanning the area including the one side is set to a predetermined value This method has the effect that the inspection processing operation can be performed in the same procedure even if the sizes of the electronic components are different.

According to a third aspect of the present invention, in the second aspect of the present invention, immediately after the laser beam scans an area including at least one side of one electronic component, the sensor head section performs the next inspection on the electronic component. The movement to an area including at least one side of the component is started.
This is a method in which the quality of two electronic components is determined, and the moving speed of the sensor head portion is set when the next electronic component is inspected. This has the effect of shortening the inspection time. Have.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, a region including at least one side of the electronic component mounted on the printed circuit board has a locus of 3 This is a method in which scanning is performed while performing a circular motion equal to or more than a rotation, and has an effect that inspection can be performed stably and accurately with little variation.

According to a fifth aspect of the present invention, in the method according to the third or fourth aspect, when the inspected electronic component is determined to be defective, the electronic component is immediately re-inspected. There is an effect that there is no extra time from the defect determination to the reinspection, and the inspection time can be shortened.

According to a sixth aspect of the present invention, in the invention of the fifth aspect, when the inspected electronic component is determined to be defective and re-inspection is performed, a region including at least one side of the electronic component is scanned. This is a method in which the number of rotations of the circular motion of the trajectory of the laser beam is increased from the previous time and the re-inspection is performed,
This has the effect that the inspection accuracy at the time of re-inspection can be improved.

According to a seventh aspect of the present invention, in the invention of the fifth or sixth aspect, when the inspected electronic component is determined to be defective and re-inspected, a laser beam is emitted from the previous electronic component. This is a method in which re-inspection is performed by scanning an area including a different side, and has an effect that inspection can be stably and reliably performed.

According to an eighth aspect of the present invention, in accordance with the invention of any one of the fifth to seventh aspects, the electronic components mounted on a plurality of printed circuit boards are sequentially arranged based on the same inspection data. In performing the inspection, when the re-inspection of a specific electronic component has reached a predetermined frequency, when the laser light scans an area including at least one side of the electronic component, the rotation speed of the circular motion of the laser light is set to be higher than normal. In this method, the number of times of reinspection can be reduced and the inspection time can be shortened.

According to a ninth aspect of the present invention, in the first aspect of the invention, when creating the inspection data, the mounting state of each electronic component is determined based on information of other electronic components arranged in the vicinity. This is a method for determining the side to be used for the inspection, and has an effect that the inspection can be surely performed.

According to a tenth aspect of the present invention, there is provided the optical lens according to the first aspect, wherein the reflected light from the inspection object is bent in a direction perpendicular to a part of the optical path of the laser beam applied to the inspection object. And a method of inspecting the mounting state of the electronic component by measuring the luminance of the reflected light from the optical lens with a luminance sensor, and has an effect that the inspection can be reliably performed.

An eleventh aspect of the present invention is the method according to the tenth aspect, wherein the phase of the wavelength of the laser light passing through the optical lens is converted by using an optical filter. This has the effect that light can be received by the luminance sensor and inspection can be performed reliably.

According to a twelfth aspect of the present invention, in the invention of the tenth aspect, a hollow through-hole for allowing a laser beam to pass therethrough is provided in the optical lens, so that the inspection can be performed reliably. It has the action of:

The invention according to claim 13 is the invention according to claim 10
12. In the invention according to any one of the above 12, when the inspection data is created, it is suitable as a result of examining a side to be used for inspection of a mounting state of each electronic component based on information of other electronic components arranged in the vicinity. In the case where no side exists, only the presence / absence of the electronic component is determined by using only the luminance sensor, and the inspection can be performed reliably.

The invention according to claim 14 is the invention according to claims 1-1.
3. In the invention according to any one of the aspects 3, when inspecting a printed board assembled by a plurality of mounting machines, the presence / absence of electronic components mounted on the printed board is determined based on mounting data used by each of the mounting machines. This is a method in which inspection data for inspecting a mounting state such as a positional shift is created, and the inspection data is synthesized and edited to inspect a printed circuit board assembled by a plurality of mounting machines. It has the effect of being able to.

The invention according to claim 15 is the invention according to claims 1-1.
4. In the invention according to any one of the aspects 4, when inspecting the presence / absence of electronic components mounted on the same type of printed circuit board and the mounting state such as misalignment by using a plurality of inspection apparatuses, Inspection data for inspecting the mounting state such as presence / absence and misalignment of mounted electronic components is divided and edited for inspection points according to each inspection device.
This is a method in which a printed circuit board is inspected by a plurality of inspection apparatuses, and has an effect that the inspection can be reliably performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view showing the structure of a device for inspecting a mounted component using the method of inspecting a mounted component according to the embodiment. , Floating, etc., and a control unit 2 connected to the inspection unit 1 by a signal cable 8 to control the inspection unit 1. The control unit 2 includes a personal computer (hereinafter, referred to as a personal computer). Personal computer).

The inspection section 1 includes a sensor head section 10 for detecting an electronic component 5 mounted on a substrate 4 to be inspected having a reference hole 6 on a base 3 and a recognition mark. X-axis robot 25 for moving, and this X-axis robot 25
An auxiliary guide 26 arranged in parallel with the axis robot 25,
A Y-axis robot 27 arranged orthogonally on the X-axis robot 25 and the auxiliary guide 26; a first conveyor rail 37 and a second conveyor rail 38 arranged to transport the substrate 4 to be inspected; Conveyor part 3 consisting of
0, a board arrival confirmation sensor 35 for detecting that the board 4 to be inspected has arrived at the inspection position, and a board pressing cylinder 41 for fixing the board 4 to be inspected so as not to be subjected to vibration when inspecting the board. And a substrate fixing section 40 composed of a substrate fixing block 42.

FIG. 2 is a block diagram showing a circuit configuration of the personal computer 2. In FIG.
The external shape information, the mounting information, and the position information (hereinafter, these are collectively referred to as inspection information) of the electronic component 5 for inspecting the electronic component 5 are input into the inside in advance.

The electronic component scanning position calculation circuit 71 determines the electronic component 5 based on the mounting position, shape, direction, etc. of the electronic component 5 to be inspected.
The scanning position of the upper sensor head 10 is calculated. The scanning signal output circuit 72 controls the X-axis robot 25 and the Y-axis robot 27 based on information from the electronic component scanning position calculation circuit 71. The rotation signal output circuit 73 uses the information from the electronic component scanning position calculation circuit 71 to output the refraction element 14 of the sensor head 10.
(Details are shown in FIG. 3). The correction circuit 74 corrects height data from the displacement sensor 11 (details are shown in FIG. 3).

The determination circuit 75 determines the presence / absence of an electronic component, a position shift, and the like based on information from the correction circuit 74. The interface circuit 76 controls the conveyor unit 30, the board arrival confirmation sensor 35, and the board fixing unit 40.

FIG. 3 shows the principle of a displacement sensor 11 for detecting the displacement of the electronic component 5. This displacement sensor 11 is an optical displacement sensor based on a so-called triangulation method, Laser light 1 emitted from the part 12a
And a hollow shaft 15 for holding the refractor 14 made of flat glass attached to refract the refractor 3.
A motor 20 capable of recognizing a position for rotating the refractor 14; a belt 18 for transmitting the rotation of the motor 20 to the hollow shaft 15; A light receiving lens 12b for condensing the reflected light diffused in 5 and a light receiving unit 12c formed of a photoelectric conversion element such as a one-dimensional PSD element.

That is, when the substrate 4 to be inspected is considered as a reference plane, the reflected light of the electronic components 5 on the substrate 4 to be inspected to the light receiving portion 12c is provided on the substrate 4 to be inspected before the light receiving portion 12c. The displacement from the displacement sensor 11 to the electronic component 5 can be detected by detecting the amount of displacement of the condensed reflected light on the light receiving portion 12c, which is collected by the light receiving lens 12b. The displacement is smaller than the reference plane. Further, by detecting the amount of light received on the light receiving section 12c, the amount of reflected light from the substrate 4 to be inspected or the electronic component 5 can be detected.

FIG. 4 is a perspective view showing details of the sensor head unit 10 attached to the Y-axis robot 27. The displacement sensor 11 is attached to a bracket 21. A bearing 16 is provided on the optical path of the laser beam 13 emitted from the light projecting portion 12a inside the displacement sensor 11, and the hollow shaft 1 having a pulley 17 coupled to the bearing 16 is provided.
5 are rotatably fitted. The hollow shaft 15 to which the pulley 17 is connected is connected to a pulley 19 via a belt 18.
Are rotated by the coupled motor 20. A refractor 14 is attached to the hollow shaft 15 at an arbitrary angle with respect to the direction of the irradiation axis of the laser beam 13.

With this configuration, when the pulley 19 rotates in the direction of arrow E in FIG. 2 as the motor 20 is driven, the pulley 17, the hollow shaft 15,
Rotate in the same direction. As a result, the laser light 13 whose optical path has been changed by the refractor 14 rotates with the rotation of the refractor 14.

Next, the operation of the mounted component inspection apparatus according to the present embodiment will be described. As shown in FIG. 1, the substrate 4 to be inspected is transported to the inspection stage by the conveyor unit 30 from the previous process, and the substrate 4
Conveyer 30 stops when the arrival of the vehicle is detected. After the conveyor unit 30 stops, the board pressing cylinder 41 attached to the first conveyor rail 37 is driven, and the board fixing block 42 attached to the board pressing cylinder 41 moves the board 4 to be inspected to the first conveyor rail. 37
Is pressed against the second conveyor rail 38 arranged in parallel with the substrate 4 and fixed so as not to move when inspecting the substrate 4 to be inspected.

Here, the sensor head section 10 for inspecting the presence / absence and displacement of the electronic component 5 is attached to a Y-axis robot 27, and is moved by the Y-axis robot 27 in a direction indicated by an arrow Y in FIG. Yes, and X-axis robot 25
Thereby, it can be moved in the direction of the arrow X in parallel with the substrate 4 to be inspected.

Therefore, the motor 2 of the sensor head 10 is based on the approximate substrate position information of the storage circuit 70 in the personal computer 2.
X-axis robot 25 and Y-axis robot 2 with 0 stopped
7 scans the displacement sensor 11 to detect the outer edge of the substrate 4 to be inspected, and further scans the displacement sensor 11 based on the approximate substrate hole position information in the memory circuit 70 to detect the reference hole 6 of the substrate 4 to be inspected. Are detected and their center position is calculated, and this center position becomes the inspection start origin.

On the other hand, since the memory circuit 70 in the personal computer 2 stores the inspection information such as the center position of the reference hole 6 of the board 4 to be inspected of the electronic component 5, that is, the position information from the inspection start origin, the inspection information is sequentially stored. The inspection information is called, and the displacement sensor 11 scans once on the electronic component 5 mounted on the substrate 4 to be inspected according to the inspection information.

FIG. 5 shows a movement in which the displacement sensor 11 scans the electronic component 5 mounted on the board 4 to be inspected. As shown in FIG. Scanning is performed by rotating the one long side approximately four times, and measurement is performed. Immediately after the scanning is completed, movement to the position of the next electronic component 5 to be inspected is started.

During this movement, the height signal generated from the displacement sensor 11 is determined by the determination circuit 75 in the personal computer 2 to determine the level of the height and the changing point of the height.
Inspection of presence, displacement, floating, etc.

The laser beam scans over one long side of the electronic component 5 by rotating about four times, and the number of rotations is constant irrespective of the size of the electronic component 5, thereby changing the height level. The number of points is set to be the same for any of the electronic components 5, and the inspection process of the electronic components 5 is performed in the same procedure from the changing point.

The number of rotations of the laser light may be about three times or more. If the number of rotations is two times or less, the height of the electronic component 5 when the long and short sides intersect with the laser light slightly increases or decreases. , The number of data at the change point changes, and the inspection accuracy decreases. In this embodiment, the number of rotations of the laser beam is set to 4
The reason is that the number of data at the height change point is increased to improve the inspection accuracy.

The rotational speed of the motor 20 is fixed and the moving speed of the sensor head unit 10 is adjusted in order to keep the scanning rotational speed of the laser beam constant even for the electronic components 5 having different sizes. Is set for one electronic component 5
After the operation of the laser beam is completed, the sensor head unit 10 is set based on the inspection information each time the sensor head unit 10 moves to the position of the electronic component 5 to be inspected next.

When the inspection of all the electronic components on the substrate 4 to be inspected is completed, the substrate pressing cylinder 41 is driven, the substrate fixing block 42 is retracted, and the substrate 4 to be inspected is moved to the conveyor section 30.
Is transferred from the inspection stage to the next process, and one cycle is completed. FIG. 6 is a flowchart showing such a flow.

Next, an inspection method of the inspection device for the mounted component according to the present embodiment will be described. First, the principle of triangulation of the sensor head 10 and the principle of rotation of the laser beam 13 will be described. FIG. 7A is a principle diagram of the triangulation.
When measuring the measurement surface 91, the laser beam 13 emitted from the light projecting unit 12 a emits B light on the measurement surface 91 if there is no refractor 14.
1, the light is diffused and reflected by the light receiving unit 12 through the light receiving lens 12b.
The light is condensed on B1a on the light receiving portion 12c, is diffusely reflected on the measuring surface 92 at B10, is condensed on the light receiving portion 12c through the light receiving lens 12b, and is condensed on the light receiving portion 12c.
The displacement between the measurement surfaces 91 and 92 is measured based on the difference between the light condensing positions a.

Here, when the measurement surface 91 is the refraction body 14 shown in FIG.
In the position indicated by the solid line in (a), the laser beam 13 irradiates B2 on the measurement surface 91 according to Snell's formula, and irradiates B3 on the measurement surface 91 when it is located in the broken line. Therefore, by rotating the motor 20 and rotating the refraction body 14 attached to the hollow shaft 15 by the belt 18, the trajectory of the laser beam 13 is as shown in FIG. Make a rotary motion.

However, when the refractor 14 is at the position indicated by the solid line in FIG. 7A, the laser beam 13 is applied to the position B2 on the measurement surface 91. 7A. When the refractor 14 is at the position shown by the broken line in FIG. 7A, the laser beam 13 is applied to the position B3 on the measurement surface 91. It is equivalent to irradiating the position of B11 on the measurement surface 93 when there is not. This means that when the refractor 14 is present, the displacement of the displacement sensor 11 changes depending on the rotation angle θ of the refractor 14 even if the measurement surface 91 does not change.
Sensor 1 when the refractor 14 is rotated once by
The output waveform of the displacement for one rotation angle θ is 200 in FIG.
become that way. Therefore, in order to prevent the displacement of the displacement sensor 11 from changing on the same measurement surface regardless of the rotation angle θ of the refractor 14, the displacement must be corrected.

Next, a method of correcting the displacement will be described. 7A, when the displacement amount S1 or S2 of the irradiation position of the laser beam 13 by the refractor 14 is converted into a change in displacement of the measurement surface 91, the change amount of the displacement of the measurement surface with respect to the displacement amounts S1 and S2 is displaced. H1 (measurement surface 92), displacement change H2 (measurement surface 93), and light receiving lens 12b
If the distance from the center of the optical axis to the laser beam 13 is X1, and the distance from the center of the optical axis of the light receiving lens 12b to the measurement surface 91 is Z1, the relational expression is (Equation 1) or (Equation 2).

[0051]

(Equation 1)

[0052]

(Equation 2)

Here, in FIG. 7 (a), if the right direction is defined as the positive direction of the X coordinate and the downward direction is defined as the positive direction of the Z coordinate, the deviation amount is S, and the change amount of the displacement is Hs. The equations of (Equation 1) and (Equation 2) are represented by (Equation 3).

[0054]

(Equation 3)

On the other hand, as shown in FIG. 7B, the laser beam 13 having rotated on the
The light is condensed on the light receiving portion 12c through the light receiving portion 2b and rotates similarly. However, since the light receiving portion 12c is a one-dimensional sensor, the position measurement depends only on the X-axis direction. Therefore, the deviation amount S is given by (Equation 4) where r is the rotation radius and r is the rotation angle.

[0056]

(Equation 4)

Here, the distance to the measurement surface 91 measured by the displacement sensor 11 when there is the refractor 14 is H, and the refractor 1
In the case where there is no 4, that is, the true distance from the displacement sensor 11 to the measurement surface 91 is Z1, and the relationship becomes (Equation 5).

[0058]

(Equation 5)

Therefore, the true distance to be obtained is expressed by the following (Equation 6) based on (Equation 3), (Equation 4) and (Equation 5).

[0060]

(Equation 6)

The distance H to the measurement surface 91 measured by the displacement sensor 11 is determined by the rotation angle θ of the refractor 14, the refractive index, the thickness, and the rotation radius derived from the angle with respect to the laser beam 13 by the Snell's formula. From the center of the optical axis of the light receiving lens 12b, which is a unique value of the displacement sensor 11,
The true distance Z by correcting the displacement from the distance X1 to 3
1 is required. When the displacement is corrected by the displacement correcting method, the waveform of the displacement 200 before the correction in FIG.

FIG. 9A shows the trajectory of the laser beam 13 when the laser beam 13 makes one rotation on the electronic component 5.
The displacement waveform measured by the displacement sensor 11 at that time is shown in FIG.
As shown in (b), the waveform 202 of the displacement before correction becomes a waveform 203 by the correction processing. This shows that the position where the displacement of the electronic component 5 changes and the thickness t can be measured.

FIGS. 10A and 10B show scanning examples when the electronic component 5 on the substrate 4 to be inspected is inspected by using such an inspection method and a correction processing method. .

Normally, the motor 20 of the sensor head 10 rotates at a constant speed, and the laser beam 13 rotates. In this state, the X-axis robot 25 or the Y-axis robot 27 scans once on the electronic component 5 (which is a square chip component in the present embodiment) on the substrate 4 to be inspected, so that the laser light 13 of the displacement sensor 11 is scanned. Traces a spiral locus 100 when viewed from the upper surface of the substrate 4 to be inspected. At this time, FIG.
By setting a threshold value 101 between the displacement level Hb of the substrate 4 to be inspected and the displacement level Ha of the electronic component 5, the displacement waveform 102 after the displacement correction processing of the displacement sensor 11 is set as shown in FIG. The changing points, W1 and W2 (the description of other changing points is omitted) can be detected.

From the displacement change point obtained in this way and the position information of the X and Y coordinates of the change point, the positional deviation in the X direction, Y
It is possible to detect a positional deviation in the direction and inspect the presence / absence, positional deviation, floating, and the like of the electronic component 5 mounted on the substrate 4 to be inspected. FIG. It is 11.

Further, by comparing the change point obtained from the inspection information stored in the storage circuit 70 in the personal computer 2 with the position of the change point obtained by scanning, the displacement of the electronic component in the same direction can be obtained. The state and the rotational misalignment state can be inspected.

Although the present embodiment has been described on the assumption that the laser light scans only one side of the electronic component, the mounting state can be inspected by scanning the other side. As a result, large parts can be inspected with high accuracy.

In the above description, the height change point is determined with a fixed threshold value. However, the height change point may be variable or may be multi-step. Even in the case of a printed circuit board on which electronic components are mounted, even when cream solder adheres to the edges of the electronic components, it is possible to accurately determine the height change point.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to FIG.

FIG. 12 is a flowchart for explaining the procedure of the re-inspection in the present embodiment. The inspection method of the present embodiment is performed by the same inspection apparatus as that of the first embodiment. And a detailed description thereof will be omitted.

FIG. 12 shows a case where the mounting state of the electronic component 5 is determined to be defective in the first embodiment, and the moving speed of the sensor head unit 10 is set to 1/3 of the normal speed when performing a re-inspection. , Indicates that a retest is performed. By doing so, the laser beam scans the electronic component 5 at 12 rotations, and the pass / fail judgment is performed by increasing the number of data at the height change points, and the mounting state of the electronic component 5 is more stably and accurately determined. Can be inspected.

Needless to say, it is not necessary to increase the number of rotations of the laser beam during the re-inspection.

Further, at the time of re-inspection, the inspection may be performed by using sides other than the previously scanned side of the electronic component 5.

Embodiment 3 Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

FIG. 13 shows that when electronic components mounted on a plurality of printed circuit boards of the same product type are sequentially inspected, a particular electronic component is determined to be defective at a predetermined frequency and re-inspected. In this case, it is described that the inspection of this specific electronic component is performed from the beginning by increasing the number of scanning rotations of the laser beam as compared with the normal inspection as in the case of the reinspection.

That is, the present invention is used when the mounting state of electronic components mounted on a certain type of printed circuit board is continuously inspected.

In this case, a retest point counter is set for each type of electronic component. This becomes a part of the memory in the storage circuit 70 in the inspection apparatus shown in the first embodiment.

Before the inspection of the first printed circuit board is started, the reinspection point counter corresponding to each electronic component is reset to zero.

Then, as shown in FIG. 13, first, as a normal inspection, the electronic component is inspected by rotating the laser beam four times. When the re-examination is performed, "+2" is input to the re-examination point counter, and the re-examination point is stored. When the inspection is completed in the normal inspection without re-inspection, "-1" is input to the re-inspection point counter, and the re-inspection point is stored. Then, the process proceeds to the inspection of the next electronic component, and similarly, the re-inspection point is stored.

The above operation is repeated until all inspections are completed. During the above operation, the re-inspection point has a predetermined value, for example, 1
When the number reaches 0, when the electronic component is inspected, the inspection is performed in detail from the beginning by setting the laser beam scanning to 12 rotations as in the reinspection.

By doing so, it is possible to reduce the time required for re-inspection of electronic components that are frequently determined to be defective, thereby shortening the entire inspection time.

(Embodiment 4) Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS.

In this embodiment, when creating inspection data, it is determined which side of the electronic component to be inspected is to be used for inspection, based on the relationship with other electronic components arranged nearby. Things.

If there is no side suitable for inspection from the relationship with other electronic components arranged in the vicinity, the central portion of the electronic component is scanned with laser light to determine only the presence or absence. It is something to do.

FIG. 14 is a flowchart showing the inspection procedure according to the present embodiment, FIG. 15 is a plan view showing the priority of the side of the electronic component used for inspection, and FIG. 16 shows the inspection failure due to the electronic components arranged in the vicinity. FIG. 17 is a front view showing a sensor head portion of the inspection apparatus according to the present embodiment.

In the present embodiment, only the configuration of the sensor head shown in FIG. 17 is different from that of the inspection apparatus of the first embodiment, so that detailed description of other points will be omitted.

As shown in FIG. 15, each of the electronic components 5 has a priority order with respect to a side used for inspection due to the attachment of the displacement sensor of the triangulation.

As shown in FIG. 16, due to the adjacency with other electronic components 5 arranged in the vicinity, at the time of scanning with laser light,
In some cases, inspection may not be possible due to the shadow of the laser light. In this case, the inspection data is created according to the procedure shown in the flowchart of FIG.

If there is no side suitable for inspection, inspection data is created so that the laser beam scans the center of the electronic component 5.

At this time, the sensor head 30 shown in FIG.
3 is used for inspection. As shown in FIG. 17, a beam splitter 301 is disposed between the light projecting unit 12 a and the refractor 14 in the sensor head unit 303, and further reflects light reflected vertically from the electronic component 5 via the beam splitter 301. And a luminance sensor 302 for receiving light.

When the laser beam scans the center of the electronic component 5, the brightness sensor 302 is used to scan the electronic component 5.
Is determined. By doing so, the presence or absence of an electronic component can be determined even if an adjacent electronic component exists.

(Embodiment 5) Hereinafter, a fifth embodiment of the present invention will be described with reference to FIG.

The inspection method according to the present embodiment is the same as the inspection method according to the fourth embodiment, except that only the configuration of the sensor head shown in FIG. 18 is different. Is omitted.

FIG. 18 is a front view showing a sensor head of the inspection apparatus of the present embodiment. As shown in FIG. 18, an optical filter 304 is provided between the refractor 14 and the beam splitter 301 in the sensor head 303. And a brightness sensor 302 for receiving, via a beam splitter 301, reflected light 305 vertically reflected from the electronic component 5.

When the laser light 13 emitted from the light projecting part 12a of the sensor head part 303 passes through the optical filter 304, the phase of the laser light changes, and the reflected light 305 vertically reflected from the electronic component 5 is again optically reflected. When passing through the filter 304, the phase of the laser light further changes.

Here, the reflected light 305 is emitted from the beam splitter 3
01 is reflected by the beam splitter 30
1, the reflected light 305 is reflected at right angles by the beam splitter 301, and the reflected light 305 can be received by the luminance sensor 302 without losing the light intensity, so that the electronic component 5 can be more stably and accurately inspected. be able to.

(Embodiment 6) Hereinafter, a sixth embodiment of the present invention will be described with reference to FIG.

The inspection method according to the present embodiment is the same as the inspection method according to the fourth embodiment, except that only the configuration of the sensor head shown in FIG. 19 is different. Is omitted.

FIG. 19 is a front view showing the sensor head of the inspection apparatus of the present embodiment. As shown in FIG. 19, the sensor head 303 has a laser between the light projecting part 12a and the refractor 14 as shown in FIG. A beam splitter 306 provided with a hollow through hole for transmitting light is arranged, and a brightness sensor 302 for receiving reflected light 305 vertically reflected from the electronic component 5 via the beam splitter 306 is arranged. ing.

The laser beam 13 emitted from the light projecting section 12a of the sensor head section 303 passes through the through hole provided in the beam splitter 306, so that the laser beam 13 passes through the refractor 14 without loss of light intensity, and The part 5 is irradiated.

At this time, the reflected light 305 vertically reflected from the electronic component 5 again enters the beam splitter 306, and the reflected light 305 is reflected at a right angle by the beam splitter 306 and can be received by the luminance sensor 302.

Thus, the electronic component 5 can be more stably and accurately inspected. (Embodiment 7) Hereinafter, a seventh embodiment of the present invention will be described with reference to FIG.

FIG. 20 shows the state of the electronic component mounted on the printed circuit board and the mounting state such as positional deviation based on the mounting data used in each of the mounting machines when inspecting the printed circuit board assembled by a plurality of mounting machines. This describes that inspection data of a printed circuit board assembled by a plurality of mounting machines is inspected by a single inspection apparatus by creating inspection data for inspecting the printed data and synthesizing and editing the inspection data. This is used when one inspection device is arranged on an integrated line in which printed boards of the same type are continuously assembled by a plurality of mounting machines.

In this case, the creation of the inspection data is the same as that described in the first embodiment, and the created inspection data is stored in the storage circuit 70 in the inspection apparatus shown in the first embodiment. And as shown in FIG. 20,
When the inspection data is synthesized and edited, necessary inspection data stored in the storage circuit 70 is extracted, and the inspection data is synthesized and edited, so that one inspection apparatus can be used for a plurality of mounting machines. It is possible to inspect the mounting state of the corresponding electronic component.

At the time of synthesis editing, inspection data may be created after the mounting data is synthesized.

Embodiment 8 Hereinafter, an eighth embodiment of the present invention will be described with reference to FIG.

FIG. 21 shows a case where a plurality of inspection devices inspect the presence or absence of electronic components mounted on the same type of printed circuit board and the mounting state such as positional deviation, and the like. It is to explain that inspection data for inspecting the mounting state such as presence / absence and misalignment is performed by inspecting a printed circuit board by a plurality of inspection devices by dividing and editing inspection points according to each inspection device. This is used when inspecting the same type of printed circuit board by a plurality of inspection apparatuses.

In this case, the creation of the inspection data is the same as that shown in the first embodiment, and the created inspection data is stored in the storage circuit 70 in the inspection apparatus shown in the first embodiment. And as shown in FIG. 21,
When the inspection data is divided and edited, the inspection data stored in the storage circuit 70 is extracted, and the inspection points are divided according to the number of the inspection devices and assigned to each inspection device.

Further, in order to maintain the balance of each inspection apparatus, the inspection points can be reset by communicating between the inspection apparatuses through the personal computer which is the control unit shown in the first embodiment. In this way, even when a plurality of inspection devices are used, the inspection time can be significantly reduced.

It goes without saying that information on test results can be communicated between test devices via the personal computer, which is the control unit shown in the first embodiment.

[0111]

As described above, according to the method of inspecting a mounted component according to the present invention, the outer shape of the electronic component is detected by scanning the mounted electronic component only once while the laser light projected from the sensor performs a rotary motion. The inspection for the presence or absence of the electronic component and the positional deviation can be performed in an extremely short time. Further, since it is not necessary to repeatedly scan the displacement sensor for each electronic component, the X-axis, Y-axis,
The movement of the axis robot does not take much time, the inspection can be performed very efficiently, and the inspection time can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a device for inspecting a mounted component according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a personal computer used in the apparatus.

FIG. 3 is a front view showing a principle diagram of a displacement sensor used in the device.

FIG. 4 is a perspective view of a sensor head portion showing a locus of refracted laser light of the device.

FIG. 5 is a plan view showing a trajectory of a laser beam on a substrate to be inspected in the apparatus.

FIG. 6 is a flowchart showing a method of inspecting the presence / absence of an electronic component and a positional shift of the apparatus.

FIG. 7A is a conceptual diagram showing the inspection principle of the same apparatus. FIG. 7B is a plan view showing the locus of the laser beam.

FIG. 8 is a waveform chart showing the inspection principle of the apparatus.

FIG. 9A is a perspective view showing a state where the laser beam of the apparatus has scanned the electronic component once, and FIG.

10A is a plan view showing the trajectory of a laser beam that scans an electronic component. FIG. 10B is a waveform diagram of the same height data.

FIG. 11 is a flowchart illustrating a method of determining the presence / absence of an electronic component and a position shift;

FIG. 12 is a flowchart for explaining a procedure of a reexamination according to the second embodiment of the present invention;

FIG. 13 is a flowchart for explaining an inspection procedure according to the third embodiment of the present invention.

FIG. 14 is a flowchart for explaining an inspection procedure according to the fourth embodiment of the present invention.

FIG. 15 is a plan view illustrating the priority order of each side of the electronic component.

FIG. 16 is a conceptual diagram illustrating an inspection failure due to an adjacent electronic component.

FIG. 17 is a front view showing a sensor head of the inspection apparatus according to the present embodiment;

FIG. 18 is a front view showing a sensor head of an inspection device according to a fifth embodiment of the present invention.

FIG. 19 is a front view showing a sensor head of an inspection device according to a sixth embodiment of the present invention.

FIG. 20 is a flowchart illustrating a procedure for synthesizing and editing inspection data according to the seventh embodiment of the present invention.

FIG. 21 is a flowchart illustrating a procedure for dividing and editing inspection data according to the eighth embodiment of the present invention.

FIG. 22 is a perspective view showing a configuration of a conventional mounted component inspection apparatus.

FIG. 23 is a plan view for explaining an inspection method using the same device.

[Explanation of symbols]

 Reference Signs List 1 inspection unit 2 personal computer 3 base 4 substrate to be inspected 5 electronic component 6 reference hole 8 signal cable 10 sensor head unit 11 displacement sensor 12a light projecting unit 12b light receiving lens 12c light receiving unit 13 laser beam 14 refractor 15 hollow shaft 16 bearing 17 , 19 Pulley 18 Belt 20 Motor 21 Bracket 25 X-axis robot 26 Auxiliary guide 27 Y-axis robot 30 Conveyor section 35 Board arrival confirmation sensor 37 First conveyor rail 38 Second conveyor rail 40 Board fixing section 41 Board pressing cylinder 42 Board Fixed block 70 Storage circuit 71 Electronic component scan position calculation circuit 72 Scan signal output circuit 74 Correction circuit 75 Judgment circuit 76 Interface circuit 301 Beam splitter 302 Luminance sensor 303 Sensor head section 304 Optical filter 305 Beam splitter having a light 306 through hole

Claims (15)

[Claims] An electronic component mounted on a printed circuit board includes information on the mounted electronic component in addition to mounting NC data used when the electronic component is mounted on the printed circuit board. Inspection data for inspecting the mounting state is created, and based on the created inspection data, a laser beam is irradiated perpendicularly to the object to be inspected, and the reflected light reflected at an angle is received via a light receiving lens. When sequentially scanning electronic components mounted on the printed circuit board using a sensor that focuses light on the photoelectric conversion element, the trajectory of the laser light moves through a region including at least one side of the electronic component mounted on the printed circuit board. A laser beam is irradiated so as to be scanned while performing a predetermined number of circular motions, and the presence or absence of an electronic component mounted based on a height signal measured by the photoelectric conversion element from the reflected light is determined. A method for inspecting a mounted component, which determines pass / fail by comparing inspection position data, positional deviation, and lift with inspection data. 2. A sensor is held in a sensor head that is movable at a variable speed in a horizontal direction, and the moving speed of the sensor head is set according to the length of one side of each electronic component to be inspected. 2. The method for inspecting a mounted component according to claim 1, wherein the rotational speed of the circular motion of the trajectory of the laser beam for scanning the area including the one side is a predetermined value regardless of the size of the electronic component to be inspected. 3. After the laser beam has finished scanning an area including at least one side of one electronic component, the sensor head immediately starts moving to an area including at least one side of the next electronic component to be inspected. While moving the head,
3. The method according to claim 2, wherein a pass / fail judgment of the two electronic components is performed, and a moving speed of the sensor head is set when the next electronic component is inspected. 4. A trajectory of a laser beam scans a region including at least one side of an electronic component mounted on a printed circuit board while performing a circular motion of at least three rotations.
3. The method for inspecting a mounted component according to any one of claims 1 to 3. 5. The method according to claim 3, wherein when the inspected electronic component is determined to be defective, the electronic component is immediately re-inspected. 6. When the inspected electronic component is determined to be defective and re-inspection is performed, the number of rotations of the circular motion of the trajectory of the laser beam that scans an area including at least one side of the electronic component is increased from the previous time. 6. The method according to claim 5, wherein the inspection is performed again. 7. The method according to claim 1, wherein when the inspected electronic component is determined to be defective and re-inspection is performed, the laser beam scans an area including one side of the electronic component different from the previous one and performs re-inspection. Item 7. The method for inspecting a mounted component according to item 5 or 6. 8. When sequentially inspecting electronic components mounted on a plurality of printed circuit boards based on the same inspection data, when a re-inspection of a specific electronic component reaches a predetermined frequency, a laser beam is used. 8. The apparatus according to claim 5, wherein, when scanning an area including at least one side of the electronic component, the scanning is performed by increasing the number of revolutions of the circular motion of the laser light to be larger than a predetermined number. Inspection method for mounted components. 9. The method according to claim 1, wherein when creating the inspection data, a side to be used for inspecting a mounting state of each electronic component is determined based on information of another electronic component arranged in the vicinity.
Inspection method for the mounted components described. 10. An optical lens which bends the reflected light from the test object in a direction perpendicular to a part of the optical path of the laser beam irradiated to the test object, and measures the luminance of the reflected light from the optical lens as a luminance sensor. 2. The method for inspecting a mounted component according to claim 1, wherein the mounting state of the electronic component is inspected by performing the measurement. 11. The method for inspecting a mounted component according to claim 10, wherein a phase of a wavelength of the laser light passing through the optical lens is converted by using an optical filter. 12. The method for inspecting a mounted component according to claim 10, wherein a hollow through-hole for passing a laser beam is provided in the optical lens. 13. When creating inspection data, there is no suitable side as a result of examining sides to be used for inspecting the mounting state of each electronic component based on information on other electronic components arranged in the vicinity. 13. The method according to claim 10, wherein only the presence / absence of the electronic component is determined using only the brightness sensor. 14. When inspecting a printed circuit board assembled by a plurality of mounting machines, the presence or absence of electronic components mounted on the printed circuit board and a mounting state such as a positional shift are determined from mounting data used by each of the mounting machines. The inspection component of any one of claims 1 to 13, wherein inspection data to be inspected is created, and the inspection data is synthesized and edited to inspect a printed circuit board assembled by a plurality of mounting machines. Inspection methods. 15. When inspecting the presence / absence of electronic components mounted on the same type of printed circuit board by a plurality of inspection apparatuses and the mounting state such as positional deviation, the presence / absence of electronic components mounted on the printed circuit board. The inspection circuit for inspecting a printed circuit board by a plurality of inspection devices by dividing and editing inspection data according to each inspection device for inspection data for inspecting a mounting state such as displacement and the like. A method for inspecting a mounted component according to one aspect.