JPS6093969A - Inspection equipment of printed wiring board - Google Patents

Abstract

PURPOSE:To obtain an inspection apparatus capable of bringing a desired checker pin into contact with a part to be inspected corresponding to an article to be inspected, by providing a drive means for protruding the checker pin to the part to be inspected and a control means for selectively activating said drive means. CONSTITUTION:When the piston, not shown by the drawing, of a pen cylinder 29 is selectively energized by compressed air or a pulse signal such as a current, a piston rod 30 is displaced upwardly. Because of this, a guide rod 27 is pushed up and a checker pin 25 is pushed up to be contacted with the part to be inspected on a pattern and locked in an upwardly displaced state. Subsequently, a coil spring 32 is inlaid with the recessed part 31 of the guide rod 27 and, therefore, the pulse signal disappears and the guide rod 27 is head to said displaced state even if the piston rod 30 is displaced downwardly while a probe 24 is brought to an upwardly protruded state. After inspection, the guide rod 27 is released from the lock state and returned to the original state by merely pressing the probe 24 downwardly.

Description

[Detailed Description of the Invention] Technical Field The present invention #'i relates to an inspection device for inspecting the circuit function of an electronic circuit of a printed wiring board to which an electronic circuit element is connected;
More specifically, the present invention relates to an inspection device equipped with a detection mechanism (hereinafter referred to as a fixture) that effectively detects a signal by pressing a checker pin against a patterned electrode portion on a substrate.

Background technology A typical fixture is shown in FIG.

In the fixture shown in FIG. 1 (1), the entire board 1 to be measured is fixed at a predetermined position, the pump (not shown) is fully activated, and air is passed through the hose 4 between the movable plate 2 and the fixed plate 3. and aspirate. Therefore, the bottom of the board 1 as well as the movable plate 2 is
The test probe 5 and the portion to be inspected 6 of the substrate 1 come into contact. The test probe 5 is connected to an interface port 8 by a wrapping wire 7, and is further connected to an eight interface port tester (not shown).

In such prior art, it is necessary to replace the entire fixture every time the model of the printed wiring board is changed, which increases the cost of the fixture when producing a wide variety of products in small quantities. Also, a large number of fixtures must be prepared and their locations must be considered. Furthermore, replacement work is troublesome.

In the other fixture shown in FIG. 1 (2), check pins 9 are set up for the least common multiple of several types of boards, and unnecessary checker pins 10 are removed by a mask plate 11 so that the boards do not come into contact with each other. That's what I do.

In such prior art, one mask plate is required for each model.
It is possible to detect the signal from the pattern electrode section by simply replacing 1. However, mask plate 1
The removal and installation of item 1 is complicated and is not sufficient as an inspection device in an automated factory.

In yet another fixture shown in FIG. 1(3), checker pins 25 are arranged in advance on a grid, and the checker pins lf't are required for each model.

The board 1 is fully equipped with the glue lid pin 12 for raising the lid and the interface pin 13 in the contact area with the necessary tester.
4 to switch the wiring between the checker pin 25 and the tester.

With such prior art, it is possible to adapt to all models by replacing the board 14, but as with the fixture shown in Figure 1 (2), the installation and removal work is complicated, and inspection equipment in automated factories is not suitable. This is insufficient.

Purpose The purpose of the present invention is to solve the above-mentioned technical problems and to provide a complete set of testing equipment for printed wiring boards that can bring desired checker pins into contact with the parts to be tested corresponding to each object to be tested. It is.

Embodiment FIG. 2 is a cross-sectional view of a part of a fixture according to the invention. A plurality of insertion holes 22 are formed in the pin board 21 . The insertion holes 22 are formed at positions corresponding to a plurality of predetermined check points when designing the printed wiring board. A roughly cylindrical receptacle 23 is inserted into the insertion hole 22 and fixed therein. This receptacle 2
A probe 24 is inserted into the interior of the probe 3 . 24 probes,
Checkered pin 25 that contacts the pattern of the printed wiring board
and a coil spring 26 that biases the checker pin 25 toward the pattern. A guide rod 27 is disposed below the probe 24 in FIG. This guide rod 27 is inserted into the insertion hole 28 of the receptacle 23 in the axial direction KG.
It is inserted so that it can be moved freely. A small so-called pen cylinder 29 is provided below the guide rod 27, and a piston rod 30 of this pen cylinder 29 is displaced upwardly to push up the guide rod 27. Further, a coil spring 32 that can be connected to the recess 31 of the guide rod 27 is attached to the lower surface of the receptacle 23.

When the piston (not shown) of the pen cylinder 29 is energized, the piston rod 30 is displaced upward.

This pushes the guide rod 27 upwards, which pushes the probe 24 and thus the checker pin 25 upward so that it can come into contact with the portion of the pattern to be inspected. The guide rod 27 is locked in an upwardly displaced state. More specifically, the recess 31 of the guide rod 27 fits into the coil spring 32, so that even if the piston J430 is displaced downward in FIG. 2, the guide rod 27 maintains its state. Probe 24 remains protruding upward.

In order to release the locked state of the guide 1 guide pin 27 and return it to its original state, the probe 24 and checker pin 25 must be moved to the second position.
Just press down on the figure.

The driving source for energizing the piston of the pen cylinder 29 to enable a series of operations is a pulse signal such as compressed air or electric current. In this way, the pushing up of the checker pin 25 and the temporary fixing can be automated.

The operation of the pen cylinder 29 is such that the guide rod 27 protrudes to perform a full pulse operation sufficient to push up the checker pin 25, and is normally a monostable type that is kept at the lowest position. Next, the relationship between the spacing between the checker pins 25 and the arrangement of the pen cylinders 29 will be explained. When setting the spacing between checker pins 25 and the number of pen cylinders 29, there are two methods: arranging the number of pen cylinders 29 corresponding to the number of checker pins 25, and arranging one or several pen cylinders 29.
There is a method in which the checker pin 25 is driven by moving the checker pin 25.

The maximum outer diameter of the checker pin 25 when it is attached to the board 2 is 'ka, the maximum outer diameter when the pen cylinder 29 is attached to the board 21 is b, and the distance between the checker pins 25 by 1 mm is 'J'. Let zx be the minimum dimension of adjacent checker pins 25 , ky be the minimum dimension of adjacent checker pins 25 , and let iz be the minimum dimension of adjacent cylinders 29 , then in the former method, the first equation holds true as a constraint on the mounting interval of checker pins 25 .

y=x-a)(1...(1) Furthermore, Equation 2 holds true as a constraint regarding the mounting interval of the pen cylinders 29.

z = x - b ) O... (2) Furthermore, since the outer diameter of the pen cylinder 29 is generally larger than the outer diameter of the checker pin 25, i11 of the checker pin 25
The third equation holds true, which shows that the distance x(d) is limited by the outer diameter a of the pen cylinder 29.

b) a...(3) To give a specific example, a = 4.0 mm, b = 7
．． 0 mm.

If the installation interval of the Ben cylinder 29 is z = 0.5 mm, then from the second formula, x = z + b = 0.5 + 7.0 = 7.5 m
m.

In the method of driving the checker pin 25 by moving one pen/cylinder, it is not dependent on the outer diameter of the pen cylinder 29, so it is determined only by the above-mentioned first equation. For example a
= 4.0 man% If y = 1.0 mm, then x = 5.0 mm.

Based on the basic method of using the checker pin 25 and the pen cylinder 29 as described above, a method of pushing the checker pin 25 toward the inspected part will be described. FIG. 3 is a diagram showing an example of the layout when setting the checker pin 25 on the jt1 printed wiring board, and FIG. This is a diagram for Referring to the 3rd Showa 1st edition, the example is - The length of the side is 247 mm.
If the checker pin 25 is set up on a printed wiring board whose other side is 328 mm long, the pin board 21 has a side length 11 of 247 mm corresponding to the printed wiring board.
mm, the length of the other side 12 is 328 mm,
In this pin board 21, the pin spacing dimension X ”k 7
．． 5 mm, and if some space is provided around the periphery to support the board, the number of pins will be 31 vertically and 42 horizontally, for a total of 1302 pins. Also, the pin spacing is 15mm,
If each is set to 15mm, the number of pins is 47 vertically.
There are 1302 flts in 63 rows and 315 rows in 15 columns and 21 rows.

In this way, the checker pins 25 are generally arranged at intervals of several mm, and therefore the number of pins is large. Therefore, it is not practical to individually provide 29 pen cylinders corresponding to each pin from the viewpoint of the outer diameter of the pen cylinder 29, production cost, and reliability. The present invention overcomes these disadvantages and provides a practical fixture that allows one or a relatively small number of pen cylinders 29 to push up the checker pin 25 in a predetermined sequence of operations. It is to be carried out according to the following.

Next, with reference to FIG. 4, one or more pen cylinders 2
9, the operation of standing the bottle will be explained. Figure 4 f
11 shows a case where 2911 pen cylinders are used and all pins are actuated on a pin board 21 in which m pins in the X direction and n pins in the X direction are arranged at intervals of X.

Is the pen cylinder 29 on the pin board 21? , 4 Figure 1
Start from the position of pin p1 at the left corner of +11, move in the X direction, complete the operation of pin pm 5.9 p m Move to +1, move in the opposite direction to the X direction, and push up the second row of pins all 111! go. In this way, the IIN next bottle is raised and the final pin pm-ni is pushed up to complete the process. The pin interval AX in this case can be set arbitrarily because one pen cylinder is used.

In FIG. 4(2), there is a pen cylinder 29 in either the row or the column.
This shows the case where all pins are fully activated in one forward scan. In the pen cylinder array 41 extending in the lateral direction in FIG. 4(2), m pen cylinders 29 are provided corresponding to m pins. This pen cylinder array 41 moves in the Y direction to actuate all pins. This method is used when X and b satisfy the fourth equation.

Work≧b (4) However, if the pin 25 and the pen cylinder 29 are connected with all the power transmission means such as a release, it can also be used for the condition x(b).

In FIG. 4(3), a pen cylinder is provided at each side of a row or column, and when all the pins 25 are operated by several short strokes, there is a surplus of water. Pen cylinder 29 in pen cylinder array 41
m/2 pieces are provided at equal intervals. When this pen cylinder array 41 moves in the Y direction and reaches the lower row, it moves in the X direction by a distance X, and then moves in the opposite direction to the X direction until it reaches the uppermost row and all pins are fully actuated. This method is used because X and b are the fifth equation? This is the case when the conditions are met.

x(b...(5) In general, this is possible when x = b/n.

However, n is a natural number. In this case, it is necessary to make a round trip n times.

In the method shown in Figure 4 +1+ to (3), the unit time required to complete pin operation is 2 seconds, and the total pin interval length is 7.5 mm.
, pin deposit m=42, n=31, totaling 1302 pins, the time required to complete the bottle stand is shown in Table 1.

The method using only one pen cylinder 29 shown by +1+ in Figure 4 of Table 1 has a setting time of 43.4 minutes, which is highly practical. However, if the number of pins is particularly small or there is no limit to the setting time, it is still practical.

In the method shown in Fig. 4 (12), the setting time is 62 seconds, and in the method shown in Fig. 4 (3), the setting time is 124 seconds.
seconds, and therefore Figures 4(2) and 4(3)
The method rrl has sufficient practicality.

The method shown in FIG. 4(3) is effective when the pin spacing length is required to be small compared to the vent cylinder 29 spacing. Of course, the method shown in FIG. 4(2) is also possible if the pen cylinder 29 and checker pin 25 are connected via a power transmission means such as a release as described above, but such a movable part? The method shown in FIG. 4 (3) in which this method is not used has higher reliability.

In the method shown in Fig. 4 (3), it is necessary to set the operation of the pen cylinder 29 to relatively +M HP, but by using a normal NC type A-Y table and performing an arbitrary program, it is possible to It is easy to set the position with high accuracy, for example, with a decoy difference of 0.05 mm.

FIG. 5 is a block diagram showing an automatic checker system for inspection equipment using the fixture according to the present invention.

A check program CPU (Central Processing Unit) system 50 inputs a program corresponding to the printed wiring board unit for all inspection purposes, and thereby the main CPU
Activate the U system 51. Main CPU system 5
1, the sensor driver buffer 53 is activated via all the system path lines 52, and all pins on the pin board 54 are brought into the output state.

On the other hand, the output from the CPU system 55 for the pen cylinder selection program for driving the pin board 54 is given to the entire controller 56, and this controller 56 operates the XY table 57 for pen cylinder control. When the XY table 57 is set at the desired position, the pen cylinder 29 causes the pin 25 of the pin board 54 to be pushed up 58 . Note that when changing the setup, it is necessary to once push down the pin 25 that has been pushed up on the pin board 54, but this pushing down mechanism is
4 is provided.

Effects As described above, according to the present invention, it is possible to bring the desired checker pin into contact with the object to be inspected, so there is no need to replace the fixture for each type of object to be inspected as in the past, and work efficiency is improved. In addition, the inspection time can be shortened, and it becomes possible to obtain an inspection device suitable for an automatic inspection system.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the prior art, FIG. 2 is a cross-sectional view of a part of the fixture according to the present invention, and FIG. 3 is a diagram showing an example of the layout when the checker pin 25 is erected on the board. FIG. 4 is a block diagram showing the automatic checker system for inspection equipment using the fixture according to the present invention. It is. 21.54... Pin board, 25... Checker pin, 27... Guide rod, 29... Pen cylinder, 30
...Piston salary, 31...Concave Fi, 32...Coil spring, 50.51.55...CPU system, 52
...System pass line, 53...Buffer, 5G
...Controller, 57...X-Y table agent Patent attorney Nishi Kyoshi Part 2 Sho 1 Figure

Claims (1)

[Scope of Claims] An inspection device for testing the circuit function of an electronic circuit by pressing a checker pin against a portion to be inspected of an electronic circuit configured on a printed circuit board to establish electrical continuity, comprising: 1. An inspection device for a printed wiring board, characterized in that it includes a drive means for projecting into an inspection part, and a control means for selectively activating the drive means.