JPS6165105A - Bend detector of ic lead - Google Patents

Abstract

PURPOSE:To speed up the detection of bend in all directions by forming two means each of which projects parallel light to through holes corresponding to the number of leads formed on one side of a guide at a fixed angle and finding out the number of times of absence of 'OR' between the outputs of photodetectors which may be obtained by transmitted light. CONSTITUTION:An IC having leads 21-214 passes on an IC guide 11 having two pairs of through holes 15-21, 15a-21a so that light beams irradiated from illumination light sources 13, 13a are interrupted from passing the through holes 15-21, 15a-21a respectively and making incident on photodetectors 22-28, 22a-28a. The outputs of the converters 22-28 and that of the converters 22a-28a are inputted to independent OR circuits respectively and the number of times of repeats from the interruption of light to '0' of the OR circuits is counted by a counter. When the counter counts '2' for the frequency turning each OR circuit to '0' and '4' in total, the leads are decided as normal, and in other cases, decides as abnormal.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an IC (Int@(rat@d C1reu)
This relates to an apparatus for detecting lead distortion of an IC during an external appearance inspection (t%) of an IC. In the figure, reference numeral 1 denotes a dual-in-package type IC to be inspected, and series leads 2 are drawn out from both sides of the IC. 3 is an IC guide that sends out this IC1, 4 is an ITV camera that takes an image of IC1, and 5 is a light source for illumination. Reference numeral 6 denotes a sampling and binarization circuit that samples and binarizes the video signal from the ITV camera 24, T indicates an image memory that stores the image after being binarized by this circuit 6, and 8
is a central processing unit such as a processor that searches for the tip point of the lead 2 from the binary image stored in the image memo U7 and detects the bending of the lead from the interval between the tip points.

Next, the operation will be explained. When the IC1 sent on the IC guide 3 comes in front of the field of view of the I'tv camera 4, the video is read. At this time, the lead part 2 of the IC 1 has a metallic luster and the mold part is made of black resin, so if the IC guide 3 is made of a material with poor reflectivity and appropriate lighting is applied, the sampling binary values can be adjusted. From the binary images A1 to A7 that pass through the conversion circuit 6 and enter the image memory 7, only the lead portion 2 of the IC 1 can be extracted, as shown in FIG. In FIG. 6, for example, the shaded area indicates the area where the picture element is 111, and the background is 10'.
This is the area of Therefore, the central processing unit 8 in FIG. 5 processes the binary image, determines the tip of the lead 2 or the center coordinates of the lead, and further calculates the lead interval from the coordinates.
11 to a6 in FIG. 6 are determined, widening or narrowing of the lead, etc. is detected, and whitening of the lead is detected.

[Problem that the invention seeks to solve]

The conventional device described above is configured as described above, so it is effective for the left and right curves as seen in Figure 6, which affect the interval between the IC leads. Since white spots cannot be detected and the image must be processed by a central processing unit, there is a limit to the speed of processing.

The present invention was made in view of these circumstances, and
The object of the present invention is to provide an ICC lead comb detection device that can detect lead white spots in all directions at high speed by checking whether or not the C lead and lead detection pattern are optically matched twice. do.

[Means for solving problems]

In order to achieve such an object, the present invention makes a certain angle in the direction in which the IC flows with respect to the side surface of the guide that sends out the RC. A group of through holes, each of which has a constant thickness and has parallel page through holes equal to the number of leads on one side of the IC, a light source that emits light parallel to the direction of each of the through holes, and a light source that emits light parallel to the direction of each of the through holes; Two sets of light-receiving elements having the same number of through-holes as the through-holes installed at positions for receiving parallel light and an OR circuit which inputs all the signals from these light-receiving elements are provided, and the IC has the same number as the through-holes. When the IC passes through a group of through-holes, it is determined whether or not there is a lead white spot on the IC based on the number of times the output signal from both of the OR circuits disappears.

[Effect]

In the present invention, the number of times the output signal from both OR circuits disappears when the IC leads are normal is used as the basis, but when there is a bent lead, the number of times is other than that, so it is based on the number of times the output signal disappears. Lead blanks can be detected.

〔Example〕

FIG. 1 is a schematic diagram showing an embodiment of the present invention. In the figure, reference numeral 11 denotes an IC guide, and through holes 15 to 21, the number of which are the number of leads 2 on one side of the IC 1 to be inspected, are formed in the side surface 12 at an angle with respect to the direction of the guide 1. The interval between the holes is equal to the interval between the leads when the leads 2 are normal, and the size of the holes is slightly smaller than the thickness of the leads 2. Reference numeral 13 denotes an illumination light source whose light rays 14 are kept parallel so as to pass through all of the through holes 15 to 21. Numerals 22-28 are photoelectric converters as light-receiving elements, which are installed at positions to receive the light that has passed through each of the through-holes 15-21. This outputs a signal when the received light signal is above a certain level, and does not output a signal when it is below that level.

Reference numeral 29 is an OR circuit serving as a logical sum circuit, which calculates the logical sum of the outputs from each of the photoelectric converters 22 to 28.

Note that this illumination light source 132 through holes 15 to 21. Photoelectric converters 22-28. There is another set of OR circuits 290, and reference numeral 29m in FIG. 1 is another set of OR circuits.

In addition, 30 is a counter that counts the number of times the output of both OR circuits 29 and 29m becomes null (also called zero), and when the count is other than 4, a lead blank is detected as a lead blank. It has become something to do.

In addition, FIG. 2 shows the through holes 15 to 21.1 of each set.
The relationship between 5 m and 21 m is shown in a diagram cut along a plane passing through the hole. In Fig. 2, those indicated by 21 to 214 are
It is a cross section of lead 2 of IC1.

In the configuration of the above embodiment, when irradiated with the light source 13,
Lead 2 of IC1 passes through holes 15 to 21 of IC guide 110
As long as the light is not blocked, the light reaches the photoelectric converters 22-28, and the photoelectric converters 22-28 output an output signal. These through holes are
Since there is a gap equal to the number of leads on one side of IC10 in the normal case, there is a gap between the leads of C1, so when a normal IC1 passes through, there is a moment when lead 2 blocks the light passing through all the through holes 15 to 21. . This occurs for the leads 2 on both sides, so in a normal case, two will occur.

Therefore, the output of the OR circuit 29 becomes zero twice.

However, if there is a bent lead 2 like lead 2A shown in FIG. 2, light will reach the photoelectric converter 22, so the output of the OR circuit 29 will not become zero. Therefore, if there is a white spot on the lead 2, the output of the OR circuit 29 will not become zero twice.

Here, as shown in FIG. 2, two types of through holes 15 to 21.
It is based on the idea that if the lead 2 is bent in the direction of T, it will not be possible to detect white spots, but if the through hole 17m is also drilled in the direction shown in Figure 4, detection will be possible even in this case. ing. Therefore, in FIG.
．． If the output from 29a does not become zero four times when passing through IC1, it can be detected that lead 2 is bent. Although the lead detection light was created, a large hole may be made in the rc guide and a light source that emits a plurality of directional light beams may be used.

〔Effect of the invention〕

As described above, according to the present invention, a plurality of thin parallel light beams whose width is smaller than the lead width are used, and matching with the lead is optically observed using the light beams. This has the effect of providing a lead 1 detection function.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of the present invention, FIG. 2 is a positional relationship diagram of the illumination light source 2 through hole and photoelectric converter in FIG. 1, and FIGS. 3 and 4 are diagrams of the above embodiment. A diagram showing the relationship between lead blanks and through-holes to explain the operation, Figure 5 is a block diagram of a conventional lead song detection device, and Figure 6 is an explanation showing an example of a binary image of the lead in the device shown in Figure 5. It is a diagram. 1 ・ ・ Rei・ IC, 2 fist 11 + 1 ・ Lead, 11 ・ ... IC guide, 13 ... e. Light source, 15 ~ 21. 15a ~ 21 Todoroki ... Through hole, 22
~28.22a~28 breath 1111・φ photoelectric converter, 29
, 29°゛゛OR circuit, 3a... proboscis/counter.

Claims (1)

[Claims] In a device that sends out a dual-in-package type IC onto a convex guide and detects the bending of the IC's lead, each of a certain thickness has a certain angle to the side surface of the guide in the direction in which the IC flows. A group of through holes with parallel through holes separated by the number of leads on one side of the IC, a light source that emits parallel light in the direction of each of the through holes, and a position that receives the parallel light after passing through each of the through holes. One set includes the same number of light-receiving elements as the installed through-holes and an OR circuit which inputs all the signals from these light-receiving elements, and two sets of these are provided, and when the IC passes through the through-hole group. . An IC lead bending detection device, characterized in that it is determined whether or not the lead of the IC is bent based on the number of times the output signal from both of the OR circuits disappears.