JPS6122268A - Inspecting machine for printed circuit board - Google Patents

Abstract

PURPOSE:To make it possible to display the trouble of a printed circuit board in a state including the positional information on a through-hole, by inputting the positional information on a probe pin by using an attached position detecting printed circuit board. CONSTITUTION:A switching circuit 8 changes over the external connection of parallel patterns provided to a position detecting printed circuit board 7 at constant intervals through a change-over circuit 9. Voltage is applied to one of prob pins 3 from an inspection machine 6 and the switching circuit 8 is changed over while a pattern issuing voltage is detected by a voltage detection circuit 10 and the position in a Y-direction is detected by the connection position of the switching circuit 8 at this time. When a position detecting printed circuit board having pattern arrangement rotated by 90 deg. is used, the position in an X-direction can be known similarly. By this method, the coordinates of each probe pin 3 can be inputted to the inspection machine 6 which can in turn output the inferior data of a printed circuit board to be tested in a state including the coordinates position of the probe pin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a printed circuit board inspection machine equipped with a position detection printed circuit board that displays the coordinate position of a check point on a printed circuit board to be inspected.

[Technical background of the invention and its problems] In general, when inspecting printed circuit boards, the terminals (
Place multiple spring contact probe pins (hereinafter referred to as probe pins) into the through-holes, etc., check for continuity or non-continuity between the probe pins, and check if the connection information is OK.
Determine defectiveness.

That is, as shown in FIG. 2, holes are machined in the pin guide jig plate 2 so that the probe pins 3 can be set up in accordance with the positions of the through holes (A, B, etc.) on the printed circuit board 1, and the probe pins 3 and the connectors are aligned with each other. The pins 5 are connected by wiring, and the other end of the connector 5 is connected to an inspection machine 6.

If you inspect through holes A and B and find a short circuit,
If the connection information shows an open circuit, it is determined that there is a short-circuit failure between A and 8, and the output of the inspection device 6 displays "short-circuit failure between ■ and ■."

However, the problem in this case is that although the inspection device 6 calls the pin of the connector 5 and outputs a failure, it cannot determine which through hole in the printed circuit board 1 that pin hits. This is because the arrangement of the probe pins 3 and the pin arrangement of the connector 5 are different, and the wiring 4 is simply connected to a nearby pin.

If you create a comparison table (for example ■-A1■-B), you can deal with it, but when the number of pins increases, it takes a lot of time to create a comparison table and to identify defective positions using the comparison table.
It's inconvenient.

[Object of the Invention] The present invention is a printed circuit board that inputs the position information of the probe pin into the inspection machine 6 using the attached position detection printed circuit board, thereby making it possible to display the fault indication including the position information of through holes, etc. The purpose is to provide a board inspection machine.

[Summary of the Invention] The present invention includes a pin guide jig plate that fixes the positions of a plurality of probe pins according to the positions of check points on a printed circuit board under test, and checks the printed circuit board under test by conduction between the probe pins. In a printed circuit board inspection machine that performs and a voltage detection circuit that scans the voltage in a linear pattern to detect the coordinate position of the probe pin in the Y direction or It has been made possible.

[Embodiments of the invention] An embodiment of the present invention is shown in FIG.

FIG. 1 shows a position detection printed circuit board 7 having parallel patterns at regular intervals (for example, 2.54 mm), a switching circuit 8 for switching external connections of each of the above patterns, a switching circuit 9 for switching the switching circuit 8, and a switching circuit. Voltage detection circuit 1 connected to the common point of 8
0 is provided, and the output of the voltage detection circuit 10 is input to the tester 6, and the tester t16 outputs a switching circuit switching signal to the switching circuit 9 to switch the switching circuit 8.

A guide pin 12 is provided on the stand 11 so that it can be moved by 1/2 of the pattern interval in the Y direction.

In the case of detection in the X direction, it can be moved by 1/2 interval in the X direction.

In FIG. 1, the jig plate 2 is omitted for clarity, but each probe pin 3 is positioned by the jig plate 2, which is made corresponding to the check points of the printed circuit board under test.

If all the probe pins 3 are arranged at a pitch of 2.541111, a voltage is applied from the inspection device 6 to one of the probe pins 3, for example C, and the switching circuit switches the voltage pattern to the voltage detection circuit. 10, and the position in the Y direction can be determined based on the connection position of the switching circuit at that time.

Furthermore, by using a position detecting printed circuit board whose pattern arrangement is rotated by 90'' with respect to FIG. 1, the position of the probe pin in the X direction can be similarly determined.

The position of the probe pin is made to match the position of the land on the printed circuit board under test.The position of the land is the position of the mounting foot of the component, so some parts have a pitch of 2.5111111 or 5IllIll. Probe pins that do not ride on the 2.54 mm+pitch pattern of the detection printed circuit board 7 come out.

For example, the probe pin E in FIG. 3 cannot be detected because it is located in the middle of the pattern of the position detection printed circuit board 7.

Furthermore, when the probe pin F contacts on the side, sufficient contact pressure may not be applied and detection may not be possible.

If such an undetectable pin occurs, move the position detection printed circuit board 7 by 1.27111 m to the left or right in the direction of the arrow in Figure 3 by moving the guide pin 12 to remove the undetectable probe. The pin can be brought into contact with the pattern and can be detected.

In this way, the coordinates (X, Y positions) of each probe pin can be input to the detector 6, and the detector outputs defective data of the printed circuit board under test including the coordinate position of the probe pin. can.

Further, it is possible to move the position detection printed circuit board by one pitch or more in order to bring the probe pins that are not in contact into contact, but if the movement amount is large, there is a drawback that the probe pins at the ends will not come into contact with each other. Further, if the relationship between the inter-pattern width a and the pattern width S in FIG. 3 is, for example, 3a<b, then the non-contact globe pin can be made conductive by moving it by 1/4 pitch.

Furthermore, as shown in FIG. 4, by widening the pattern width of the position detection printed circuit board 7 and narrowing the distance between the patterns, all probe pins can be detected. Since both patterns show continuity,
It can be judged as intermediate.

Further, the printed circuit board 7 for position detection does not have to be a printed circuit board, but can be replaced as long as it has conductors arranged in parallel.

Furthermore, in the above explanation, a voltage is applied to the probe pin 3 to detect the voltage of the pattern on the position detection printed circuit board 7, but it is also possible to apply voltage to the pattern sequentially and detect the voltage with the probe pin. good.

[Effects of the Invention] As explained above, according to the present invention, a printed circuit board for position detection having patterns at regular intervals is used as an inspection jig, and the continuity detection function of the inspection machine is used to easily detect the position detection. The positions of the probe pins in the X and Y directions can be detected, and the inspection results of the printed circuit board can be output including position information in the XYh directions, making it easy to find defective parts.

Also C A D (Computer A 1ded
It becomes possible to input the positional information of each point and determine whether the connection is good or not.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of a printed circuit board inspection machine according to the present invention, Fig. 2 is a block diagram showing an example of a conventional printed circuit board inspection machine, and Fig. 3 is an example of a state in which probe pins cannot be detected. The figure shown in FIG. 4 is a diagram showing a detection state of a probe pin with a wider pattern width. , 1... Printed circuit board under test 2... Pin guide jig plate 3... Probe pin, 4... Wiring 5... Connector, 6... Inspection machine 7... Print for position detection Board 8... Switching circuit 9... Switching circuit, 10... Voltage detection circuit 11...
Stand, 12...Guide pin agent Patent attorney Noriyuki Chika (1 idiot) 2nd
Figure fI6 Figure 3 Figure 4 JK

Claims (2)

[Claims] (1) In a printed circuit board inspection machine that is equipped with a pin guide jig plate that fixes the positions of multiple probe pins according to the positions of check points on the printed circuit board under test, and that checks the printed circuit board under test by the conduction between the probe pins. , a position detection printed circuit board having a linear pattern in the X direction or Y direction at regular intervals; a stand for fixing the position detection printed circuit board at a predetermined coordinate position in order to bring the position detection printed circuit board into contact with the plurality of probe pins; It is characterized by having a voltage detection circuit that scans the voltage of the pattern to detect the coordinate position of the probe pin in the Y direction or the X direction at the check point, and outputs the check information of the printed circuit board under test together with the position information of the check point. Printed circuit board inspection machine. (2) The printed circuit board inspection machine according to claim 1, further comprising a moving device that moves the coordinate position of the position detection printed circuit board by a fraction of the pattern interval.