JPH06249629A - Method and device for inspecting electronic part - Google Patents

Abstract

PURPOSE:To simultaneously detect the floating, omission, and abnormal inter- lead pitch of leads with a simpler constitution. CONSTITUTION:A laser unit 26 is constituted of a laser emitting section 27a which emits laser light 32 toward the lead row of electronic parts 18 and light receiving section 27b which receives the laser light 32 passed through the lead row. In addition, the laser unit 26 is inclined so that the laser light 32 can be obliquely emitted against the lead row of the parts 18 from the top to the bottom and can be obliquely received by the light receiving section 27b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting an electronic component for detecting an abnormality of a lead forming a lead row of a flat package IC or the like when mounting the electronic component on a printed circuit board. .

[0002]

2. Description of the Related Art Flat package ICs are used for electronic parts.
It is well known that a lead row in which a large number of leads are arranged in parallel is provided on the side of the package, such as (hereinafter abbreviated as IC). In such an IC, due to deformation of the leads, some leads may float above other leads, or the pitch between adjacent leads may become narrower (wider). If an IC having a non-uniformity is attached to the substrate, the leads may be disconnected or short-circuited, leading to conduction failure.

Therefore, in order to prevent such inconvenience, the state of the leads of each IC is inspected before mounting on the substrate, and ICs that may cause the above inconvenience are selected in advance.

Various types of lead inspection devices as described above have been proposed. For example, a lead is photographed by using an image pickup device such as a CCD, and the photographed image is processed by a processing device. Device for recognizing floating, omission and pitch between leads (Japanese Patent Laid-Open No. 62-2459)
No. 06, JP-A-63-102294), or irradiating a parallel light flux from the light projecting portion from the side surface of the lead,
A device for detecting the floating of the lead by comparing the amount of received parallel light flux that passes through the lead and is received by the light receiving unit with the reference amount of received light for the lead in proper condition (Japanese Patent Laid-Open No. 3-80600), etc. Is proposed.

[0005]

However, the above-mentioned JP-A-62-245906 and JP-A-63-1022 are known.
In a device such as that disclosed in Japanese Patent Publication No. 94, floating of leads,
Although it is advantageous in that it is possible to inspect the gap and the pitch between leads at the same time, it requires an image pickup device such as a CCD or an image processing device, so that not only the device itself becomes large, but also the equipment cost increases due to the introduction of the image pickup device. There is inconvenience. On the other hand, the device disclosed in Japanese Patent Laid-Open No. 3-80600 described above is advantageous in that the floating of the lead can be detected with a simple configuration provided with a pair of the light projecting unit and the light receiving unit, but the floating of the lead is detected. There is an inconvenience that the pitch between leads and the lack of leads cannot be inspected only by the pair of the light emitting unit and the light receiving unit.

The present invention has been made in order to solve the above problems, and provides an inspection method and apparatus for an electronic component capable of simultaneously detecting floating, missing lead and abnormal lead pitch with a simpler structure. The purpose is to do.

[0007]

The invention according to claim 1 is
In a method of inspecting an electronic component including a lead row in which a plurality of leads are arranged in parallel, a predetermined angle from diagonally above to diagonally below or diagonally above from the diagonally downward with respect to the lead row of the electronic component. The lead abnormality of the electronic component is detected by detecting the shadow portion interval due to the lead of the received parallel light while irradiating the parallel light.

According to a second aspect of the present invention, in an electronic component inspection apparatus for inspecting an electronic component having a lead row in which a plurality of leads are arranged in parallel, a parallel light beam is emitted toward the lead row of the electronic component. And a light receiving unit that receives parallel rays that have passed through the lead row, and includes a light ray detection unit that detects an abnormality of the lead based on projection detection of the lead row of the electronic component. The light beam is emitted to and received by the lead row of the electronic component at a predetermined angle from obliquely upward to obliquely downward or obliquely downward to obliquely upward.

[0009]

According to the invention described in claim 1, the parallel rays are irradiated to the lead row of the electronic component at a predetermined angle from obliquely upward to obliquely downward or obliquely downward to obliquely upward. By receiving the light, it is possible to simultaneously detect the floating state of each lead in the lead row, the missing state, and the lead pitch state.

According to the second aspect of the invention, the floating state of each lead in the lead row, the missing state and the state of the lead pitch can be detected simultaneously by the light beam type detecting means consisting of a pair of irradiation section and light receiving section. it can. Therefore, it becomes possible to inspect an electronic component with an extremely simple structure as compared with a device that recognizes the state of the lead row using an image pickup device such as a CCD, and does not require an image pickup device such as a CCD. Therefore, the equipment can be downsized or the equipment cost can be reduced.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

1 to 4 show the structure of an electronic component mounter to which the electronic component inspection apparatus of the present invention is applied.
As shown in the figure, a conveyor 2 for conveying a printed circuit board is arranged on a base 1 of an electronic component mounting machine (hereinafter, abbreviated as a mounting machine), and a printed circuit board 3 is conveyed on the conveyor 2. And is stopped at a predetermined mounting work position.

On the side of the conveyor 2, a parts supply section 4 is provided.
Are arranged. The component supply unit 4 includes a large number of rows of tape feeders 4a, and each tape feeder 4a is a reel in which small pieces of electronic components such as ICs, transistors, and capacitors are stored and held at predetermined intervals. In addition, the tape feeding end is provided with a ratchet type feeding mechanism so that the tape is intermittently fed as chip components are picked up by a head unit 5 described later.

A head unit 5 for mounting components is installed above the base 1. The head unit 5 is movable in the X-axis direction (direction of the conveyor 2) and Y-axis direction (direction on the horizontal plane orthogonal to the X-axis).

That is, a pair of fixed rails 7 extending in the Y-axis direction and a ball screw shaft 8 rotatably driven by a Y-axis servomotor 9 are arranged on the base 1, and the fixed rails 7 are mounted on the fixed rail 7. A head unit support member 11 is arranged in the head unit, and a nut portion 12 provided on the support member 11 is screwed onto the ball screw shaft 8. A guide member 13 extending in the X-axis direction and a ball screw shaft 14 driven by an X-axis servomotor 15 are arranged on the support member 11, and the head unit 5 can be moved on the guide member 13. A nut portion 17 held and provided on the head unit 5 is screwed onto the ball screw shaft 14. Then, the ball screw shaft 8 is rotated by the operation of the Y-axis servomotor 9 to move the support member 11 in the Y-axis direction, and the ball screw shaft 14 is rotated by the operation of the X-axis servomotor 15, so that the head unit is rotated. 5 is a support member 1
It moves in the X-axis direction with respect to 1.

Further, the Y-axis servomotor 9 and the X-axis servomotor 15 are provided with position detecting means 10 and 16 each comprising an encoder so that the moving position of the head unit 5 can be detected. It has become.

The head unit 5 includes an electronic component 18
A suction nozzle 19 for sucking is provided so as to be able to move up and down and rotate. In this embodiment, as shown in FIG. 3, the head unit 5 includes a mounting member 20 supported by the guide member 13 and a head 21 mounted on the mounting member 20.
And a suction nozzle 19 that can be moved up and down with respect to the head 21 and can rotate about the R axis (nozzle center axis).
And have. The mounting member 20 is provided with a nut portion 17, and the head 21 is provided with a Z-axis servo motor 22 for raising and lowering the suction nozzle and an R for rotating the suction nozzle.
The axis servo motor 24 is mounted. The servo motors 22 and 24 are provided with position detecting means 23 and 25, respectively. Further, an interference position detecting means 31 (FIG. 5) for detecting an interference position between the suction nozzle 19 and the component supply unit 4 (see FIG. 5).
Is attached to the head unit 5.

A laser unit 26 as an optical detecting means is rotatably attached to the lower end of the head unit 5. This laser unit 26
Is a laser irradiating section (irradiating section for parallel light rays) 2 which faces each other across a space through which the suction nozzle 19 moves up and down.
7a and a light receiving section 27b (shown in FIGS. 2 and 4), and a laser having a width wider than at least the lead row width of the electronic component 18 picked up by the suction nozzle 19 from the laser irradiation section 27a. Light (parallel rays) is received by the light receiving unit 2
Irradiation is directed toward 7b.

On the side of the lower end of the head unit 5,
A laser unit rotation servomotor 28 for rotating the laser unit 26 is attached, and by driving the servomotor 28, the laser unit 26 is initially set as shown by a two-dot chain line in FIG. The laser unit 26 is tilted by being rotationally displaced between the position and the detection position shown by the solid line. Further, the laser unit rotating servomotor 28 has position detecting means 29 for detecting the rotational position of the laser unit 26.
Is provided.

Next, the control system of the mounting machine having the above structure will be described with reference to FIG. FIG. 5 is a block diagram showing an embodiment of a control system of the mounting machine.

In the figure, the Y-axis servo motor 9, the X-axis servo motor 15, and the suction nozzle 19 of the head unit 5 are shown.
Z-axis servo motor 22, R-axis servo motor 2 for
4. The servo motors 28 for rotating the laser unit 26 with respect to the laser unit 26 and the position detecting means 10, 16, 23, 25, 29 provided in these servo motors are electrically connected to the axis controller (driver) 41 of the main controller 40. Connected to each other. The laser unit 26 is electrically connected to the laser unit arithmetic section 30, and the laser unit arithmetic section 30 is connected to the main arithmetic section 43 via the input / output means 42 of the main controller 40. Further, the interference position detecting means 31
Are connected to the input / output means 42.

Here, the main arithmetic unit 43, via the axis controller 41, controls each of the servomotors 9, 15, so that the work of sucking and mounting the components is automatically performed when the electronic components are mounted.
22 and 24 are controlled, and at the time of component inspection, the laser unit rotating servomotor 28 is controlled so as to rotate the laser unit 26. Also, at the time of parts inspection, the laser unit 2
6 based on the detection signal output from 6
In addition to making a pass / fail judgment of, based on this pass / fail judgment,
The operation of each of the servomotors 9, 15, 22, 24 is controlled in order to select the suction electronic component 18.

Next, the inspection of the lead rows of the electronic components in the mounting machine will be described with reference to FIGS. 7 to 9 and the flowchart of FIG. In the present embodiment, as the electronic component 18, as shown in FIG. 4, a case where a quad flat package IC in which a lead row including a plurality of lead pins 51 is provided on four side surfaces 50a to 50d of the package is applied is applied. explain.

First, as shown in FIG. 7A, when the electronic component 18 is picked up from the component supply section 4 by the suction nozzle 19, the servo motor 28 for rotating the laser unit is driven in step S1, and the laser unit is rotated. The rotation of 26 is started. As a result, the laser unit 26
7 reaches an inspection position (shown in FIG. 7 (b)) inclined by a predetermined angle, the driving of the servo motor 28 for rotating the laser unit is stopped, and the laser beam 32 from the laser irradiation section 27a is emitted from the electronic component 18. It will be irradiated from diagonally above. At this time, the laser light 32 emitted from the laser irradiation unit 27 a is blocked by the electronic component 18.

When the laser unit 26 is tilted as described above, then the suction nozzle 19 is started to rise, and along with this, the laser beam 32 in the cutoff state by the electronic component 18 is gradually increased. The light receiving portion 27b is irradiated. Then, the total laser light 32 is received by the light receiving unit 27.
At the time point of irradiation of b, the suction nozzle 19 is temporarily stopped from moving up, and then moved down by a minute distance (ΔZ). That is, the suction nozzle 19 receives the entire laser light 32 from the light receiving portion 27b.
As shown in FIGS. 4 and 7C, the laser beam 32 emitted from the laser irradiation section 27a is moved down by a minute distance (ΔZ) from the position where the lead pin 51 of the electronic component 18 is irradiated. Is radiated to the tip portion of (step S2 to step S4).

Then, as described above, when the laser beam 32 is applied to the tip end portion of the lead pin 51 of the electronic component 18, one side surface of the electronic component 18 is detected in step S5 based on the projection detection of each lead pin 51 of the lead row. The lead row on the side (side surface 50a) is inspected. Specifically, the laser light 32 applied to the lead row is blocked by each lead pin 51 and applied to the light receiving section 27b, so that the light receiving section 2 is provided.
At 7b, the laser light 32 is received in a state where a shadow corresponding to each lead pin 51 is generated. Therefore, in the lead row in the normal state, as shown in FIG.
Since the shadows 52 of are generated at equal intervals, this interval Wa
The state of the lead row is inspected by detecting (distance between shaded portions).

For example, as shown in FIG. 8A, when one lead pin 51 is in a floating state with respect to another lead pin 51 in the lead row on the side surface 50a of the electronic component, or one lead pin. When 51 is missing, the floating lead pin 51 or the missing lead pin 51 cannot block the laser beam 32, so the light receiving unit 2
In FIG. 7B, as shown in FIG. 9B, an extremely wide space Wb is generated with respect to the proper space Wa of the shadow 52. By detecting this, the lead pin 51 is detected.
Floating and missing are detected.

Further, as shown in FIG. 8B, one lead pin 5 is provided in the lead row on the side surface 50a of the electronic component.
When the pitch between the lead pins 51 is not proper because 1 is biased to the side of the adjacent lead pins 51, in the light receiving portion 27b, as shown in FIG. With respect to a wide space Wd and a narrow space Wd
The positions of 2 and 3 are generated adjacent to each other with the shadow 52 interposed therebetween, and by detecting this, an abnormality in the pitch between the lead pins 51 is detected.

In this way, the side surface 50a of the electronic component 18 is
When the inspection of the lead row in (3) is completed, the suction nozzle 19 is then rotated by 90 °, and the inspection of the lead row on the side surface 50b is performed. When the inspection of the lead row on the side surface 50b is completed, the suction nozzle 19 is similarly rotated and the inspection of the lead row on the side surfaces 50c and 50d is sequentially performed (step S6).

When the inspection of each lead row on each side surface 50a to 50d of the electronic component 18 is completed in step S5, the electronic component 18 is selected based on the inspection result (step S7). Here, when a lead abnormality such as floating of the lead pins 51 or abnormality in the pitch between the lead pins 51 occurs in any of the lead rows of the electronic component 18, it is determined whether the lead abnormality is within the allowable range. If it is determined that the value is out of the allowable range, the process proceeds to step S8 and, for example, the electronic component 1
8 is placed and stored in a defective component storage tray or the like. On the other hand, in step S7, even if the electronic component 18 is a non-defective product or a lead abnormality occurs, if it is determined that the abnormal state is within the allowable range, the electronic component 18 is sucked by the suction nozzle 19. Printed circuit board 3
The process is transferred to the predetermined mounting position of No. 1 and the present flowchart is finished.

As described above, according to the present invention having the above-described structure, in the apparatus for detecting the lead abnormality of the lead row based on the projection detection of each lead pin 51 of the lead row, in particular,
Since the laser unit 26 is tilted to irradiate the laser beam 32 obliquely above the electronic component 18 to inspect the lead row, the laser unit 26 including the pair of laser irradiation units 27a and light receiving units 27b is provided. With such a simple configuration, it is possible to simultaneously detect any floating or missing lead pin 51 in the lead row and an abnormal pitch between the lead pins 51. Therefore, as compared with a device that recognizes the state of the lead row using a conventional image pickup device such as a CCD, it becomes possible to inspect the electronic component 18 with a very simple structure, and the image pickup device such as a CCD is used. Since it is not necessary, it is extremely advantageous in terms of downsizing the equipment or reducing the equipment cost.

The specific structure of the present invention can be modified in various ways other than the above embodiment. For example, in the above embodiment, the laser unit 26 is tilted by rotating and displacing the laser unit 26. However, the laser unit 26 is tilted in advance and moved horizontally. The laser irradiation unit 27
The electronic component 18 may be interposed between a and the light receiving portion 27b, or conversely, by horizontally moving the suction nozzle 19, the laser irradiation portion 27a and the light receiving portion 27b of the inclined laser unit 26 are separated. You may make it intervene.

Further, at the time of inspecting the electronic component 18 in the above embodiment, the interval Wa between the shades 52 on the lead pins 51 in the light receiving portion 27a is detected, and the abnormality of the lead row is detected from this interval Wa. This is also one detection means for detecting abnormality in the lead row, and for example, the number of lead pins 51 in the lead row is stored in advance, and the actual number of shades 52 in the light receiving section 27a is obtained at the time of inspection, It is also possible to detect whether the lead pin 51 is floating or missing by comparing the above.

Further, in the above embodiment, the package 4
The example of inspecting the quad flat package IC in which the lead rows including the plurality of lead pins 51 are provided on the side surfaces 50a to 50d has been described, but the present invention is also applicable to other ICs and the like, and in the above-described embodiment, The example in which the invention is applied to the mounter of the electronic component 18 has been described.
Of course, it is also possible to use the inspection device alone.

[0035]

As described above, according to the present invention, the parallel rays in the light ray type detecting means for detecting the abnormality of the lead based on the projection detection of the lead row of the electronic component are directed to the lead row of the electronic component. Irradiation and light reception are performed at a predetermined angle from diagonally above to diagonally below or diagonally from below to diagonally above, so that the lead floats with a simpler configuration.
It is possible to detect the missing and the lead pitch abnormality at the same time.

[Brief description of drawings]

FIG. 1 is a plan view showing an electronic component mounter to which an electronic component inspection apparatus of the present invention is applied.

FIG. 2 is a front view of FIG.

FIG. 3 is an enlarged view showing a head unit.

FIG. 4 is an enlarged perspective view showing a laser unit.

FIG. 5 is a block diagram showing a control system of an electronic component mounter to which the electronic component inspection apparatus of the present invention is applied.

FIG. 6 is a flowchart showing an inspection procedure for a lead row of an electronic component.

7A is a schematic view showing a state where an electronic component is picked up, FIG. 7B is a schematic view showing a state where a laser unit is tilted, and FIG. 7C is a lead row of the electronic component being a laser. It is a schematic diagram showing the state set to the inspection position of a unit.

FIG. 8A is a schematic view showing a state where leads are lifted up in an electronic component, and FIG. 8B is a schematic diagram showing a state where an inter-lead pitch of the electronic component is abnormal.

9A is a schematic diagram showing a light receiving state of a light receiving unit for a normal lead row, FIG. 9B is a schematic diagram showing a light receiving state of a light receiving unit when lead floating occurs, and FIG. 6 is a schematic diagram showing a light receiving state of a light receiving unit when an abnormality occurs in a lead pitch.

[Explanation of symbols]

 18 electronic parts 26 laser unit 27a laser irradiation part 27b light receiving part 38 laser light 51 lead

Claims (2)

[Claims] 1. A method of inspecting an electronic component having a lead row in which a plurality of leads are juxtaposed, wherein the lead row of the electronic component is obliquely above and obliquely downward or diagonally below and obliquely upward. A method for inspecting an electronic component, comprising detecting a lead abnormality of the electronic component by detecting a shadow portion interval of the received parallel light beam while radiating a parallel light beam at a predetermined angle. 2. An electronic component inspecting apparatus for inspecting an electronic component having a lead row in which a plurality of leads are arranged in parallel, and an irradiating section for radiating parallel rays toward the lead row of the electronic component. A light receiving section for receiving parallel light rays that have passed through the lead row, and a light beam type detection means for detecting abnormality of the lead based on projection detection of the lead row of the electronic component, wherein the parallel light ray is the electronic component. The device for inspecting electronic parts is characterized in that the lead row is irradiated and received at a predetermined angle from obliquely upward to obliquely downward or obliquely downward to obliquely upward.