JPH073330B2 - Lead bending inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] A lead bending inspection apparatus for inspecting a lead bending amount of a component, in which a lead position of the component is accurately aligned using a licensor to measure the lead bending amount with high accuracy. The position setting processing unit that sets the lead of the component whose bending amount is to be inspected to the imaging position of the licensor and the lead set by this position setting processing unit are attached to the component. A lead amount calculation processing unit that calculates the lead bending amount based on the reference image of each lead near the root and the bending image at the position of the tip of the lead is calculated by the bending amount calculation processing unit. When the bending amount exceeds a predetermined value, it is determined to be defective.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead bending inspection device that inspects a lead bending amount of a component.

[Problems to be solved by conventional technology and invention]

The use of high-density mounting components is increasing as the density of printed circuit boards increases. There is a flat lead package type IC as one of these parts. If the lead part is bent when soldering it to a printed circuit board, defective soldering will result, so this bend of the lead part is not contacted. It is desired to measure and inspect with high accuracy and speed.

Conventionally, bending inspection of the lead part of flat lead package type IC is performed by imaging the lead part using a TV camera or a one-dimensional licensor, A / D converting the video signal, and then measuring the bend amount of the lead part from the digital signal. The method of measuring is taken.

However, with the miniaturization of the target IC, in order to obtain sufficient measurement accuracy, the ITV camera has a small number of constituent pixels per side of the CCD element, so the magnification is increased and captured in multiple screens. However, there is a problem in that the processing is complicated and the measurement and inspection cannot be performed quickly and with high accuracy.

Further, since the one-dimensional licensor can obtain only one-dimensional information, there is a problem that a measurement error occurs due to the positional deviation between the IC to be inspected and the one-dimensional licensor.

It is an object of the present invention to accurately align the lead position of a component using a licensor and to measure and inspect the bending amount of the lead with high accuracy.

[Means for solving problems]

 FIG. 1 shows the principle configuration of the present invention.

In FIG. 1, the position setting processing unit 1 uses the image signal of the lead (lead portion) of the component imaged by the licensor to accurately set the position of the lead portion to the image capturing position of the licensor.

The bending amount calculation processing unit 2 calculates and measures the bending amount of the lead portion of the component set by the position setting processing unit 1 (for example, the bending amount of the tip portion with respect to the root portion where the lead portion is attached to the component). is there.

The determination unit 3 determines that the bending amount calculated by the bending amount calculation processing unit 2 is defective when the bending amount is equal to or larger than a predetermined value.

[Action]

The present invention, as shown in FIG. 1, uses an image signal obtained by capturing an image of a lead portion of a component by a licensor to accurately align the lead portion with a predetermined position of the licensor and then The amount of bending between the reference position (for example, the root of the lead portion of the component) and the tip of the lead portion is calculated, and when the calculated amount of bending is equal to or greater than a predetermined value, it is determined that the defect is defective.

Therefore, it is possible to accurately determine the quality of the lead portion of the component by setting the lead position of the component using the one-dimensional licensor having a large number of pixels and measuring the bending amount of the lead portion with high accuracy.

〔Example〕

Next, the configuration and operation of one embodiment of the present invention will be sequentially described in detail with reference to FIGS.

FIG. 2 shows a block diagram of an embodiment of the present invention. In the figure, the slit illumination 4 is for generating and irradiating a slit-shaped light beam to the lead portion 5.

The lead portion 5 is a lead portion of an IC to be inspected (flat lead package type IC) 7. In the present invention, this lead portion 5
The amount of bending is accurately measured to determine pass / fail.

The light receiving system lens 6 forms a silhouette image of the lead portion 5 illuminated by the slit illumination 4 on the licensor 8.

The licensor 8 is a one-dimensional licensor and one-dimensionally and highly accurately detects the silhouette image of the lead portion 5.

The A / D and sensor controller 9 controls the licensor 8 and converts the detected image into a digital amount.

The memory A10-1 and the memory B10-2 are for temporarily storing the digital image signals picked up and converted by the licensor 8 and are, for example, image signals of the root portion of the lead portion 5 (a reference of the bending amount and Image signal) and an image signal at the tip of the lead portion 5 (an image signal to be measured for the amount of bending) and the like, respectively.

The video data processing unit 11 includes a memory A10-1 and a memory B10.
The position and bending amount of the lead portion of the component are calculated as will be described later based on the image signal stored in -2.

The system control unit 12 sends a signal to the head unit controller 13 to precisely move the position of the lead unit 5 of the inspection target IC 7 attached to the head 14 to a predetermined position,
Also, the quality of the lead portion 5 is determined by comparing the bending amount of the lead portion 5 with a standard value (reference value).

Next, the operation of the configuration shown in FIG. 2 will be described with reference to FIG.

In FIG. 3, the state shown in FIG. 3 is set to the component inspection position. This means that the inspection target IC 7 to be inspected by measuring the bending amount is attached to the head 14.

The figure shows a state of capturing an image. This means that a silhouette image of the IC 7 to be inspected or the lead portion 5 of the IC 7 illuminated by the slit illumination 4 is formed on the licensor 8 by the light receiving system lens 6 and captured as an image signal.

The figure shows the state of binarization. This means that the image signal taken in via the A / D and the sensor controller 9 is binarized and stored in the memory A10-1 or the memory B10-2.

The figure shows a state in which the position is set. This means that the lead portion 5 of the IC 7 to be inspected is aligned with the inspection position by the processing of FIGS. 4 to 7 described later so that the image is accurately captured by the licensor 8.

The figure shows a state in which an image is captured (root portion).
This is an image of the root part of the lead portion 5 which becomes the reference image,
It is meant to be taken in by the licensor 8.

The figure shows the state of binarization.

In the figure, the state of storing in the memory B is shown.

As a result, the reference value of the root portion of the lead portion 5 is stored in the memory B.

The figure shows a state in which an image is captured (the tip portion).
This means that the licensor 8 captures an image of the tip portion of the lead portion 5 that is the bending amount to be measured.

The figure shows the state of binarization.

In the figure, the state of storing in the memory A is shown.

As a result, the measured value at the tip of the lead portion 5 is stored in the memory A.
It has been stored in.

The figure shows a state in which the EOR logical operation of the reference value stored in the memory B and the measured value stored in the memory A is performed to calculate the bending amount of the tip portion of the lead portion 5.

In the figure, the state of judging the quality is shown. This means that when the bending amount of the tip portion of the lead portion 5 calculated in the figure exceeds a predetermined value, the inspection target IC 7 having the lead portion 5 is determined to be defective.

Next, the position setting in FIG. 3 will be sequentially described in detail with reference to FIGS. 4 to 7.

FIG. 4 is an explanatory view of the positional deviation of the lead parts. In FIG. 4 (a), the solid line shows the initial mounting position of the inspection target IC 7, and the dotted line shows the inspection position corrected by the procedure of FIGS. 5 to 7 described later. The inspection position after the correction (after the alignment) is made to match the imaging position by the lisensor 8 (not shown), for example, the lateral direction. To move from the initial mounting position of this solid line to the inspection position (head center) of the dotted line, the coordinates X, Y, and the angle θ are set as shown in FIG. 4 and enlarged as shown in FIG. First, the center position of the inspection target IC 7 may be moved to the head center position and the angle θ may be set to zero. As the movement setting procedure, for example, a procedure of moving in the order of angles θ, Y, and X will be described in detail below with reference to FIGS. 5 to 7.

FIG. 5 shows a θ direction alignment explanatory diagram. Figure 5 (a)
At the imaging position of the licensor 8 shown on the lower side of the inspection target IC7
When the lead portion 5 is imaged, a licensor output signal as shown on the upper side is obtained. In this licensor output signal,
The distance until the lead portion 5 is first detected is l ₀ .

The imaging position of the licensor 8 shown on the lower side of FIG.
When the lead portion 5 is imaged at a position where the inspection target IC 7 is moved by Δα in the Y-axis direction, a licensor output signal as shown on the upper side is obtained. In this licensor output signal, the distance until the lead portion 5 is first detected is l ₁ .

The angle Δθ (tilt) of the IC 7 to be inspected is calculated based on the initial installation distance l ₀ detected by the above procedure and the distance l ₁ when the distance Δα is moved in the Y-axis direction, as shown in the following formula (1). Become.

Δθ = tan ⁻¹ (Δα / (l ₀ −ll ₁ )) (1) Therefore, the head 14 on which the IC to be inspected is mounted by the correction angle −Δθ with respect to the angle Δθ calculated by the formula (1).
Is rotated so that the lead portion 8 of the IC 7 to be inspected is aligned with the imaging direction of the licensor 8 (lead portion 5
And the licensor 8).

FIG. 6 shows a Y direction alignment explanatory diagram. When the lead portion 5 of the inspection target IC 7 is imaged at the image pickup position of the licensor 8 shown in the lower side of the figure, the tip of the lead portion 5 is parallel to the licensor 8 due to the alignment in the θ direction in FIG.
Move the IC7 to be inspected in the Y direction (vertical direction in the figure),
The tip of the lead portion 5 is aligned with the imaging position of the licensor 8. In this moving operation for matching, the initial value is set to 1/2 of the length of the lead portion 5, and the moving amount is sequentially halved each time it is moved. More specifically, the lead portion 5 is imaged using the licensor 8 and the number of pixels of the lead portion 5 is accumulated. If the number of pixels at this time is larger than "0" (zero), in the -Y direction,
If it is smaller than “0” (zero), it is moved in the Y direction by the above movement amount. After moving, take an image using the licensor 8,
The same operation is repeated until the movement amount becomes 1. If the lead length is “L”, the tip of the lead portion 5 where the number of pixels is “0” (zero) or more is set at the image capturing position of the licensor 8 by the movement of (log ₂ L−1) times. .

FIG. 7 shows an X-direction alignment explanatory diagram. This is the sixth
Since the tip of the lead portion 5 is set so as to match the image pickup position of the licensor 8 by the alignment in the Y direction in the figure, the inspection target IC 7 is moved by half the length of the lead portion 5 from this set state to the lower side. When the image is picked up by using the licensor 8 after being set at the position shown in the drawing (set at substantially the center), a licensor output signal as shown on the upper side is obtained. The distances from both ends of this licensor output signal to the lead portion 5 are respectively set to l _L and l _r as shown in the figure. The amount of deviation in the X direction is ΔX = l _L −l _r (2) A signal corresponding to -ΔX is sent to the head controller 13 so as to correct this deviation amount, and the IC to be inspected 7
To move.

As described above, by correcting the θ direction, the Y direction, and the X direction, the tip of the lead portion 5 can be accurately set to the inspection position with respect to the licensor 8.

Next, the calculation of the bending amount in FIG. 3 will be described in detail with reference to FIG.

FIG. 8A shows the length measurement position. The upper length measurement position A represents a portion for measuring the bending amount of the tip of the lead portion 5, and the lower length measurement position B represents a reference portion of the root portion of the lead portion 5. These length measuring positions A and B are shown in FIG.
Due to the directional alignment, the center of the length of the lead portion 5 is
Since it is set at the image pickup position of the licensor 8, it is set by about a half of the length of the lead portion 5 by moving the inspection target IC 7 in the −Y direction and the + Y direction.

FIGS. 8B and 8C show the measurement position A in FIG.
And data A (measurement target value of the amount of bending) and data B (reference value, standard value) measured using the licensor 8 at the position of the length measurement position B, respectively.

FIG. 8 (d) shows FIG. 8 (b) data A and FIG. 8 (c).
The result of calculating the EOR (exclusive OR) with the data B is shown. By this, the reference value (value at the root of the lead part 5)
The bending amount of the tip of the lead portion 5 with respect to is calculated. At this time, when the result of the EOR operation uniformly appears at any of the read positions (n-2, n-1, n, n + 1, n + 2 ...), it was explained using FIG. θ
Since it is found that the directional alignment is insufficient, the correction is performed again.

〔The invention's effect〕

As described above, according to the present invention, by using an image signal obtained by capturing an image of the lead portion of a component by the licensor, the lead portion is accurately set at a predetermined position of the licensor, and the reference position of the lead portion of the component (for example, A one-dimensional licensor with a large number of pixels is adopted because a configuration is adopted in which after calculating the amount of bending between the root part of the part) and the tip, and when the calculated amount of bending is greater than or equal to a predetermined amount, it is determined as defective. Can be used to accurately set the lead position of the component, measure the bend amount of the lead with high precision, and determine whether the lead portion of the component is good or bad accurately. In particular, since the one-dimensional licensor is used, the amount of information is reduced, the processing speed is high, and there is no measurement error of the bending amount due to the positional deviation that is likely to occur in the one-dimensional licensor.

[Brief description of drawings]

FIG. 1 is a block diagram showing the principle of the present invention, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is a flowchart for explaining the operation of the present invention.
FIG. 4 is an explanatory view of positional deviation of lead parts, FIG. 5 is an explanatory drawing of θ-direction alignment, FIG. 6 is an explanatory drawing of Y-direction alignment, and FIG.
The figure shows the X-direction alignment diagram, and FIG. 8 shows the curve amount measurement diagram. In the figure, 1 is a position setting processing unit, 2 is a bending amount calculation processing unit, 3
Represents a determination unit, 5 represents a lead unit, 7 represents an IC to be inspected, and 8 represents a licensor.

Claims (1)

[Claims] 1. A lead bending inspection apparatus for inspecting the bending amount of a lead of a component, wherein the lead of the component whose bending amount is to be inspected is positioned in the θ direction, the X direction and the Y direction with respect to the imaging position of the licensor. A position setting processing unit (1) for alignment, a reference image of each lead near the root where the lead set by the position setting processing unit (1) is attached to a component, and a bend at the position of the tip of the lead. A bending amount calculation processing unit (2) for calculating the bending amount of the lead based on the image, and when the bending amount calculated by the bending amount calculation processing unit (2) exceeds a predetermined value, it is determined as a defect. A lead bending inspection apparatus characterized by being configured to make a determination.