JPS63133007A - Mounting inspection equipment for chip part - Google Patents

Abstract

PURPOSE:To judge the mounting state of a chip part instantaneously and accurately, by projecting three lines on the chip part to detect the position of the lines varying with the mounting condition of the chip part. CONSTITUTION:Lines projected on a chip part 3 to be inspected and a line pattern on a printed circuit board 4 are read out with a photographing section 5 set thereabove. An image signal thus obtained is subjected to an image processing, for example, mesh method and a line pattern alone is taken out by digital conversion with an A/D converting section 6. Then, computation is performed with a detection circuit section 7 based on a value of the position of a desired code existing in an assumed range from the line pattern to judge mounting state of the chip part 3. A signal is sent to a driving section of an X-Y table 9 from a control section 8 according to the processing state of the detection circuit section 7 to drive it. This shifts the inspection of mounting to the subsequent chip part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a testing device for semiconductor devices, and more particularly to a testing device for determining the mounting status of chip components mounted on a printed circuit board.

[Prior Art] Conventionally, when inspecting the mounting of chip components mounted on a printed circuit board, the actual situation is that an operator uses a magnifying glass to inspect the mounting status of each chip component.

Another inspection method that is used is to shine light onto the printed circuit board surface diagonally from above and determine the mounting status based on the shadows caused by the chip components.

Furthermore, this method was developed as a different inspection method, and the slit light generated when the printed circuit board or slit light passes through the edge of the chip component by slightly moving the printed circuit board or slit light in the vertical and horizontal directions relative to the chip component using an actuator. There is a method of detecting edges by reading changes in

[Problems to be Solved by the Invention] The conventional inspection methods described above each have the following problems.

■ Workers must inspect each individual chip component, resulting in extremely poor work efficiency, and inspection omissions and inspection errors inevitably occur.

■ When determining based on the state of the shadow caused by the chip component, for example, if there are variations in the dimensions of the chip component, there is a possibility of erroneous detection because the length of the shadow changes because the shadow is caused by light from one direction.

(2) Inspection using minute movements of printed circuit boards or slit light improves inspection accuracy, but it takes a long time to detect each chip component, and the equipment is expensive.

The present invention has been made to solve these problems, and an object of the present invention is to provide a chip component mounting inspection device with high accuracy and high throughput.

[Means for Solving the Problems] The mounting inspection device according to the present invention has at least one line intersecting one opposite side on the upper plane of a rectangular parallelepiped chip component mounted on a printed circuit board, and the other opposite side. Form at least two lines that intersect. Furthermore, means for reading and outputting the intersection positions of the at least three lines with the opposite sides, and means for determining the mounting state of the chip component based on the output intersection positions are provided.

[Operation] In this invention, the positions of the three lines projected on the chip component change depending on the thickness and positional deviation of the chip component, so the mounting state of the chip component is determined based on the change in the position. Detect.

[Example code] FIG. 1 is a perspective view showing an embodiment of the present invention.

In the figure, a printed circuit board 4 on which a chip component 3 is placed is placed on an X-Y table 9 that is movable on the surface.

As light sources forming two lines in the X-axis direction on the surface of the printed circuit board 4, an X-axis slit light source section 2 and a Y
A Y-axis slit light source section 1 is installed obliquely above the X-Y table 9 as a light source that forms one line in the axial direction. In addition, one of the chip components 3 is projected with three lines, and the projected portion and its surroundings are imaged, for example, 1. An imaging unit 5 such as a T, a V, and a camera is installed above. The imaging section 5, the A/D conversion section 61, the detection circuit section 7, and the control section 8 are connected to each other, and the control section 8
is an X-axis direction drive circuit section 13 and a Y-axis direction drive circuit section 12 that are connected to an X-axis direction drive section 11 and a Y-axis direction drive section 10 for moving the X-Y table 9 on a surface to control their driving. Connect each.

FIG. 2 is an enlarged perspective view of lines projected onto a chip component according to an embodiment of the present invention, and FIG. 3 is a plan view thereof.

In both figures, an X-axis groove A17 and an X-axis groove B18 are formed by projecting two slit lights that form an X-axis line A14 and an X-axis line B15 in the X-axis direction on the top surface of the chip component 3. and also in the Y-axis direction
A Y-axis groove 19 is formed by projection of one slit light beam forming the axial line 16. Reference symbols A and A6 indicate the positions at the ends of the chip components 5 of each line.

The operation of this mounting inspection device will be explained below based on FIGS. 1 to 3.

From the control section 8 to the X-axis direction drive circuit section 13 and Y.

The X-axis direction drive section 11 and the Y-axis direction drive section 10 are driven by the signal given to the axial direction drive circuit section 12 to move the X-Y table 9 and move the X-axis direction line A14 on the printed circuit board 4. Then, set the regular chip component so that its center is located at the midpoint between the two intersections of the X-axis direction line B15 and the Y-axis direction line 16. The lines projected onto the chip component 3 to be inspected and the line pattern on the printed circuit board 4 are as shown in FIG. For example, image processing such as the mesh method is performed, and the A/D converter 6 performs digital conversion to extract only the line pattern. Next, in the detection circuit section 7, a third
The positions of symbols A and -A6 shown in the figure are detected, and the following calculation is performed based on the value of the position of the desired symbol existing in the assumed range to determine the mounting state of the chip component 3. Depending on the processing status of the detection circuit section 7, a signal is sent from the control section 8 to the drive section of the X-Y table 9, and by driving this, the next chip component 3 is inspected for mounting.

Next, the detection principle of a specific mounting inspection of a chip component by reading a line pattern will be explained.

FIG. 4 is a diagram in which the chip components are mounted in a rotationally misaligned state, and here, for example, the X-axis direction line A14 and
With the midpoint between the two intersections of the axial direction line B15 and the Y-axis direction line 16 as the coordinate origin, coordinate axes are set with the X axis in the horizontal direction and the Y axis in the vertical direction, and for example, the coordinates of code A are set. Coordinates are similarly given to the other symbols A2 to A6 as (X, , 3'+). Then the line A + A 2 ,
A 3 A4, A! The midpoint of A6 is B, ,B2 respectively.
,B, and the coordinates are Bi (Xi,,Yi)(i
=1 to 3).

At this time, if the angle of rotational deviation of the chip component 3 is θ, then the coordinates of the center position O of the chip component 3 are (X
o ,, Yo ), the center position 0 is a straight line 8182
Since it passes through B and becomes the intersection of straight line B and a straight line perpendicular to B2, X(1-nX1 + (in) X2YO-nY,
+ (1-n)Y2. Furthermore, the heights H2 and H6 of the chip component 3 at the positions of the reef 2 and A6 are the distances in the Y-axis direction between the X-axis direction line B15 and the X-axis inside B18, and the distance between the Y-axis direction line 16 and the Y-axis inside 19. Based on the distance a in the X-axis direction from

Hz=a xtan a'' H6=bxtan a'' Here, α is the angle between the slit light and the printed circuit board shown in FIG.

Therefore, lines A, A2, A3 A4, A5A
By reading the position of the end of , and the end of the line of the printed circuit board, the position of the midpoint B, ~B, that is, the rotational deviation, positional deviation, and floating state of the chip component 3 can be determined. The mounting state of the chip component 3 can be detected by comparing the coordinates (Xo, YO) of the center position with a predetermined reference value (0,0) in the detection circuit section 7, for example.

According to the above detection principle, by moving the X-Y table 9 and projecting a line at each center position of the regular chip components stored in advance, inspection is performed one after another. The mounting status of all of the above chip components can be inspected.

In addition, in the above embodiment, two parallel lines and one line are made perpendicular to each other on the printed circuit board, and one of the two lines and a line perpendicular to this are made to intersect with each other at right angles to the printed board. The angles formed by the two are all set to be the same, but this is for convenience in calculation, and it is possible to detect even outside these conditions by considering the arithmetic expression.

Further, in the above embodiment, the slit light is a bright ray, but the same effect can be obtained even if it is a dawn ray that brightens the line portion.

Furthermore, in the above embodiment, X-Y
Individual chip components are inspected by moving the table, but multiple sets of lines and multiple imaging units are used to inspect the X-
It is also possible to inspect by fixing or moving the Y table.

[Effects of the Invention] As explained above, this invention projects three lines onto a chip component and detects the position of the line that changes depending on the mounting state, and instantly performs a mounting inspection. This has the effect of providing a chip component mounting inspection device with good performance and excellent throughput.

[Brief explanation of the drawing]

All drawings depict one embodiment of the invention.
FIG. 1 is a perspective view of the structure, FIG. 2 is an enlarged perspective view of lines projected onto a chip component, and FIGS. 3 and 4 are diagrams showing line patterns in various mounting states of the chip component. In the figure, 3 is a chip component, 4 is a printed circuit board, 5 is an imaging section, 6 is an A/D conversion section, 7 is a detection circuit section, 8 is a control section, 9 is an X-Y table, and 14 is a line in the X-axis direction. A11
5 is the X-axis direction line B, 16 is the Y-axis direction line, 17
18 is the X-axis inside A, 18 is the X-axis inside B119 is the Y-axis inside. Note that the same reference numerals in each figure indicate the same or corresponding parts. (2 others) 'r-ae'1 Figure 2 +5:X? White f'J opposite in B 16: Ye force gradient line 17:

Claims (1)

[Scope of Claims] A mounting inspection device for a rectangular parallelepiped chip component mounted on a printed circuit board, comprising: at least one wire on the top surface of the chip component that intersects with a first opposite side of the top surface. a first line forming means for forming a line; a second line forming means for forming at least two lines intersecting a second opposite side different from the first opposite side on the upper plane; a detection means for detecting an intersection point between the line of the book and the first opposite side and the second opposite side; and based on the intersection point detected by the detection means, midpoint positions of at least three of the lines. A first straight line connecting the midpoints of two lines formed by the second line forming means and a line formed by the first line forming means are calculated.
A second straight line passing through the midpoint of the book line and perpendicular to the first straight line.
calculation means for determining the center position of the chip component by calculating the intersection with the straight line, and further determining the rotation angle of the chip component based on the intersection position; comparing the position and the rotation angle with a predetermined center position and rotation angle;
A chip component mounting inspection device, comprising: a determining means for determining the mounting status of the chip component.