JP3127588B2 - Inspection jig for printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jig for inspecting a printed wiring board, particularly a configuration around a probe which exerts an excellent effect on inspection of a high-density wiring circuit, and electrical connection and disconnection with an inspector. And a structure around the terminal board to facilitate the above.

[0002]

2. Description of the Related Art Various methods have been proposed for inspecting a wiring circuit on a printed wiring board based on the presence or absence of electrical continuity, and an apparatus therefor (for example, Japanese Patent Application Publication No. Hei.
44035, JP-A-56-11060). As a conventionally used jig for inspecting a printed wiring board, as shown in FIGS. 12 and 13, a stylus 92 of the probe 9 is brought into contact with a wiring circuit 75 of the printed wiring board 7. Is used to check for electrical continuity.

The inspection jig comprises a guide plate 8 for preventing rattling of the tip of the probe, a pin board 88 for holding the probe 9, and a probe 9 having both of them penetrated and mounted. The probe 9 has a pipe-shaped socket 91 and a stylus 92 as shown in FIG.
The socket 91 is inserted and fixed in the through hole 881 of the pin board 88. On the other hand, the stylus 92 is inserted into the guide hole 81 of the guide plate 8 so as to be able to advance and retreat. The stylus 92 has a plunger 920 on its upper part. The plunger 920 is mounted in the lumen of the tube 25 via a spring (not shown) so as to be able to advance and retreat.

The upper end of the probe 9 is electrically connected to a tester for detecting electrical continuity via a lead wire. In this case, the connection between the upper end of the probe and the lead wire is often made by soldering.
The guide plate 8 has a concave portion 82 for arranging the lower end of the socket 91. The probe 9 is provided at a position corresponding to the wiring circuit 75 of the printed wiring board 7 as an object to be inspected. The guide plate 8 and the pin board 8
8 is integrally fixed.

When inspecting the electrical continuity of the wiring circuit, the guide plate 8 is placed from above and below the printed wiring board 7.
Then, the pin board 88 is lowered and raised to bring the stylus 92 of the probe 9 into contact with the stylus pad of the wiring circuit 75 (hereinafter, omitted). At this time, if the wiring circuit 75 has not been disconnected or short-circuited, normal electrical conduction can be obtained. Thus, the quality of each wiring circuit 75 can be determined.

In the above, the tip 921 of the stylus 92
Is brought into contact with the wiring circuit 75, the stylus 92 retreats toward the socket 91 along the guide hole 81 of the guide plate 8, and
The plunger 920 enters the socket 91.
This is to protect the tip 921 of the stylus 92.
In FIG. 12, reference numerals 87 and 886 denote insertion holes for knock pins 891, and reference numerals 871 and 885 denote positioning pins 89.
2 is an insertion hole.

[0007]

However, the above-described conventional inspection jig has the following problems. That is, in recent years, the density of wiring circuits in printed wiring boards has been increasing, and the pitch of pads at the ends of the wiring circuits has become increasingly narrower.
For example, this pitch is about 0.65 mm in the past, but is reduced to 0.3 mm in a high-density wiring circuit.

To cope with this, the probe 9
Since it is necessary to reduce the arrangement pitch of the probe, the size (diameter) of the probe itself also needs to be reduced. In the probe 9 currently used, the outer diameter of the socket 91 is about 1 mm, and the diameter of the stylus 92 is as small as 0.5 mm.

In the conventional inspection jig, the tip 921 of the stylus 92 is directly connected to the wiring circuit 75 during the inspection.
Is in contact with At the time of the contact, as described above, the stylus 92 slides in the guide hole 81 of the guide plate 8 and retreats. After the inspection, the stylus 92 is again projected to the original position by a spring spring provided in the socket 91. Therefore, the stylus 92 slides in the guide hole 81 every time the inspection is performed.

Therefore, the stylus 92 is easily worn. In addition, if the diameter of the guide hole 81 is increased to prevent this wear, the clearance between the guide hole 81 and the stylus 92 is increased, and the tip 921 of the stylus 92 may rattle, resulting in an inspection failure. The stylus 92 is inserted into a socket 91 fixed to the pin board 88. Therefore, the axes of the socket 91, the stylus 92, and the guide hole 81 must be the same. Therefore, in order to smoothly slide the small-diameter stylus 92, the guide hole 81 needs to be drilled with high dimensional accuracy so that the axes match.

The stylus 92 slides coaxially in the socket 91 and the guide hole 81, and the tip 921 of the stylus 92 directly contacts the wiring circuit 75. Vulnerable to damage. As described above, in the conventional inspection jig, there is a problem with the increase in the density of the wiring circuit, particularly, in the reduction in diameter and damage of the probe stylus 92, the accuracy of drilling the guide hole 81, and the like.

Further, the upper end of the probe is electrically connected to an inspection device via a lead wire, and the inspection circuit is electrically closed. Conventionally, the upper ends of a large number of probes of several tens to several hundreds and the lead wires are connected by soldering, and the other ends of the lead wires are connected to an inspection device.

On the other hand, since the arrangement pattern of the probes changes each time the printed wiring board changes, it is necessary to replace the so-called detection section around the probe for each printed wiring board. Therefore, at the time of this replacement, a large number of the above soldering between the probe and the lead wire must be removed,
The removal work requires large man-hours. Also, a large number of lead wires and probes must be soldered again according to the new inspection circuit.

Further, as described above, since the probe is a small-diameter part, it is an expensive precision machined part. Therefore, it is costly to use a new probe every time the wiring circuit of the device under test changes. Therefore, it is also desired that the probe can be reused. The present invention has been made in view of the above-mentioned conventional problems, and has been developed to reduce the diameter of a stylus of a probe and prevent damage, to facilitate electrical connection and removal with an inspection device, and to reuse a probe. It is intended to provide an inspection jig.

[0015]

The present invention relates to an inspection jig for inspecting a wiring circuit on a printed wiring board based on the presence or absence of electrical continuity. The inspection jig includes a guide plate, a pin board, and the above-mentioned wiring circuit. The probe comprises a contact pin for making contact with the probe and a probe having a built-in stylus for making contact with the contact pin, and the contact pin is mounted on the guide plate so as to be able to advance and retreat. A terminal board is provided outside the pin board, and a plurality of jack-type terminals, one end of which is connected to the tester, are arranged on the terminal board. A lead wire is connected to the jack type terminal, and the tip of the lead wire is removably inserted and fixed to the jack type terminal.

The first point which is most noticeable in the present invention is that the probe of the conventional example is divided into two sets,
The contact pin and the probe are configured such that the contact pin is brought into contact with the wiring circuit, while the stylus of the probe is brought into contact with the contact pin.

That is, contact pins are attached to the guide plate facing the printed wiring board so as to be able to advance and retreat, and a probe is fixed to the pin board facing the guide plate. And
The probe has a built-in stylus that is elastically movable.
Thus, as a means for incorporating the stylus, there is a means for elastically holding the stylus in the tube and mounting them in the socket (see FIGS. 4 and 5). There is also a means for inserting a direct contact needle into the probe to elastically hold it. As a means for elastically holding, there is a spring.

The contact pins are mounted in the guide holes of the guide plate so as to be able to advance and retreat. The contact pin has a tip for making contact with the wiring circuit, and has a contact part for making the stylus contact with the opposite side. Preferably, the contact portion has a head having a larger diameter than the body of the contact pin. Further, it is preferable to provide a curved concave portion in the corresponding contact portion in order to ensure the contact of the stylus (see FIG. 6). In the inspection jig of the present invention, the guide pins and the pin board are provided with the contact pins and probes having the above-described configuration according to the present invention. A relatively large diameter probe pin similar to the example can be provided.

Another thing to note in the present invention is that the means for electrically connecting the probe to the inspection device is
A terminal board is provided outside the pin board, and a plurality of jack-type terminals, one end of which is connected to an inspection device, are arranged on the terminal board, while a lead wire is connected to the probe by soldering or the like. The other end of the lead wire is detachably inserted and fixed to the jack type terminal.

That is, a terminal board is provided between the inspection device and a so-called detection section around the probe. One of the terminal boards is electrically connected to the tester, and the other is connected to the probe. The connection between the terminal board and the probe is made by inserting the lead wire connected to the top of the probe into the jack type terminal. Note that the coating and coating on the terminal portion of the lead wire are removed in advance. The jack-type terminals on the terminal board have a structure in which the connection of the probe lead wire is easy to remove and insert.

[0021]

In the inspection jig of the present invention, a contact pin is provided on a guide plate and a probe is provided on a pin board.
The contact pins are brought into contact with the wiring circuit of the printed wiring board, and the probe stylus is brought into contact with the contact pins. That is, in the present invention, a portion (contact pin) that slides in the guide hole and contacts the wiring circuit and a probe that is a detection terminal of electrical conduction are divided into two parts. Therefore, the advance and retreat of the contact pin and the advance and retreat of the stylus of the probe are independent of each other.

Therefore, it is not necessary to precisely align the three axes of the probe fixed to the pin board, the stylus inserted therein, and the guide hole of the guide plate in which the contact pins advance and retreat. Therefore, it is sufficient that the guide hole is bored in accordance with the wiring circuit of the printed wiring board, and high precision is not required as in the related art, and drilling is easy. In addition, since the guide hole only needs to allow the contact pin to slide smoothly, a small-diameter one can be provided, and rattling of the contact pin can be reduced. Further, when the contact pin is worn, it can be easily and inexpensively replaced.

Further, since the probe is not brought into direct contact with the wiring circuit, there is no damage as in the prior art.
In addition, the contact pin directly contacts the wiring circuit and slides in the guide hole. However, unlike the conventional probe stylus, the contact pin does not move linearly in both the guide hole and the probe socket. No damage due to misalignment.

Further, as described above, since the contact pins and the probes are divided so as not to cause excessive advance and retreat during the inspection, the diameters of both can be reduced. Therefore, inspection of a high-density wiring circuit is also easy. In addition, the probe is elastically and removably mounted in a socket having a small inner diameter of 0.1 to 0.3 mm. Therefore, it is an expensive precision component, but since there is no damage as described above, the cost of the inspection jig is also reduced.

Further, the inspection jig of the present invention facilitates electrical connection between the inspection device and a so-called detection section around the probe. That is, in the present invention, by inserting the lead wire attached to the probe into the jack type terminal provided on the terminal board, the inspection device and the detection unit can be easily electrically connected. Also, by pulling out the lead wire from the jack-type terminal, the detection unit can be easily separated from the inspection device.

For this reason, it is extremely easy to replace the detecting section when the printed wiring board to be inspected is changed. In the present invention, the lead wire is attached to the top of the probe by soldering or the like, and the other end of the lead wire has a structure in which the coating is removed and the wire is exposed. Therefore, the lead wire does not hinder removal when the probe is removed from the pin board. Therefore, the probe can be easily detached from the pin board and the guide plate with the lead wire having the other end opened.

Further, as described above, the contact pins can be easily removed. Therefore, the probe and the contact pin, which are precision processed parts and are expensive, can be removed from the pin board and the guide plate, and attached to another detecting portion for reuse. Therefore, according to the present invention, it is possible to reduce the diameter of the stylus of the probe and to prevent the damage, and it is possible to easily connect and disconnect the probe with the inspection device, and to reuse the probe and the contact pin. A plate inspection jig can be provided.

[0028]

【Example】

Embodiment 1 An inspection jig for a printed wiring board according to an embodiment of the present invention will be described with reference to FIGS. In addition, the whole configuration was changed by contact pins being in contact with the printed wiring board.
The detection unit for transmitting a signal to the other end of the probe and the relay unit from the upper end of the probe to the inspection device via a lead wire will be described separately.

As shown in FIGS. 1 to 3, the detecting portion of the inspection jig of this embodiment includes a guide plate 8, a pin board 88, a contact pin 3 for making contact with a wiring circuit 71, and the contact pin 3. And a probe 1 having a built-in stylus 2 for making contact with the probe 1. The contact pins 3 are mounted on the guide plate 8 so as to be able to advance and retreat, and the stylus 2 is built in the socket 11 of the probe 1 so as to be elastically advanceable and retractable. As described later, the lead wire 15 connected to the probe 1 is detachably inserted into the jack type terminal 41 of the terminal board 4 (FIG. 10).

The wiring circuits 71 are arranged at high density on the printed wiring board 7. The guide plate 8 and the pin board 88 are detachably connected to each other by a knock pin 891 as in the conventional art. As shown in FIGS. 1 to 3, 7 and 8, the guide plate 8 has a large number of guide holes 8 for mounting the contact pins 3 so as to be able to advance and retreat.
5 and an opening groove 86. Also, the pin board 88
As shown in FIGS. 2 and 3, the probe 1 has a through hole 882 for inserting and fixing the socket 11 of the probe 1.

As shown in FIGS. 2, 3 and 6, the contact pin 3 has a tip 31 for making contact with a wiring circuit 71 and a head as a contact portion for making the stylus 2 contact. It has a part 32. Also, the head 32 has a curved concave portion 321.
(FIG. 6). As shown in FIGS. 2 to 5, the probe 1 includes a socket 11 and a stylus 2 inserted into the socket 11 so as to be able to advance and retreat. The socket 11 is a hollow pipe as shown in FIG.
Has zero. A lead wire 15 is connected to the upper end 12 of the probe 1 by soldering.

On the other hand, the stylus 2 is mounted in the tube 25 so as to be able to advance and retreat as shown in FIGS. That is, as shown in FIG. 5, the stylus 2 has a guide column 22 having substantially the same diameter as that of the stylus 2 at the upper portion, and a connecting portion 21 having a small diameter therebetween. Then, first, the spring 23 is inserted into the tube 25, and then the stylus 2 is inserted. Then, the tube 25 is swaged at the outer portion of the connecting portion 21 of the stylus to form the swaged portion 251. .

Thus, the stylus 2 is elastically mounted in the tube 25 by the spring spring 23 so as to be able to advance and retreat. The reference numeral 252 indicates the tube 25.
And a caulking portion provided at the upper end portion for contacting the upper end of the spring 23. Then, the stylus 2 thus configured is inserted into the hollow portion 111 of the socket 11 as shown in FIG. At this time, the upper end of the tube 25 holding the stylus 2 is
Abut. Further, the probe 1 constructed as described above
Is inserted into the through-hole 882 of the pin board 88 as shown in FIGS. Others
This is the same as the conventional example.

Next, the operation and effect of the detection unit will be described.
That is, in order to inspect the quality of the wiring circuit 71 on the printed wiring board 7 by electrical continuity, as shown in FIGS. 1 to 3, the guide plate 8 and the pin board 88 are moved closer to each wiring circuit 71 in the vertical direction. Then, the guide plate 8 faces the printed wiring board 7.

At this time, before the contact between the two, the contact pins 3 are in a state protruding from the guide plate 8 as shown in FIG. Also, the head 3 of the contact pin 3
The tip 21 of the stylus 2 of the probe 1 is in contact with 2. Then, the guide plate 8 comes into contact with the printed wiring board 7,
When the tip 31 of the contact pin 3 comes into contact with the wiring circuit 71, the contact pin 3 slides up in the guide hole 85. Then, as shown in FIG. 3, the tip 31 of the contact pin comes to the same position as the lower surface of the guide plate 8.

Therefore, the head 32 of the contact pin 3 is
The stylus 2 is pressed in the direction of the probe 1. Therefore, the stylus 2 enters the tube 25 against the urging force of the spring 23 (FIG. 5). As described above, after the tip 31 of the contact pin 3 comes into contact with the wiring circuit 71, the probe 1, the stylus 2,
By passing a current through the contact pin 3, the quality of the wiring circuit 71 is determined in the same manner as in the prior art (FIG. 1).

After the inspection, the guide plate 8 and the like are moved away from the printed wiring board 7. Therefore, the contact pin 3 protrudes as shown in FIG. 2 by the urging force of the spring 23 of the stylus 2. As described above, in the inspection jig of this embodiment, the contact pins 3 are mounted on the guide plate 8 so as to be able to advance and retreat, and the probe 1 is fixed to the pin board 88 and the stylus 2 is able to advance and retreat into the probe 1. I am wearing it.

Therefore, the advance and retreat of the contact pin 3 and the advance and retreat of the stylus are independent of each other. Therefore, as in the prior art, the three axes of the probe 1 fixed to the pin board 88, the stylus 2 inserted therein, and the guide hole 85 of the guide plate on which the stylus advances and retreats with high precision. You don't have to. That is, in this example, even if the axis of the contact pin 3 and the axis of the stylus 2 are misaligned, there is no problem as long as they are in contact (FIGS. 2 and 3).

For this purpose, the guide hole 85 may be formed in accordance with the wiring circuit of the printed wiring board. Therefore, high precision is not required for the drilling accuracy with respect to the axis of the guide hole 85 and the hole of the pin board 88, and the drilling is easy. Further, since the guide hole 85 only needs to allow the contact pin 3 to slide smoothly, a small-diameter guide hole can be provided without rattling.

Further, since the probe 1 does not directly contact the stylus 2 with the wiring circuit 71, there is no damage as in the conventional case. In addition, the contact pin 3 directly contacts the wiring circuit 71 and slides in the guide hole 85. However, as in the case of a conventional probe stylus, the contact pin 3 moves linearly in both the guide hole 85 and the probe socket. There is no. Therefore, there is no damage due to misalignment between the two.

Furthermore, since the contact pins 3 and the probe 1 are divided so as not to cause excessive movement during the inspection, the diameters of the two can be reduced. In this example, the diameter of the contact pin 3 is 0.27 mm, and the outer diameter of the socket of the probe 1 is 0.45.
mm, inner diameter is 0.27 mm, outer diameter of stylus 2 is 0.15 m
m. In the contact pin 3 of this example,
Since a curved concave portion 321 is provided in the head 32, the head 3
The tip 20 of the stylus 2 can be reliably brought into contact with the stylus 2.

Next, the relay portion (the portion from the upper end of the probe to the inspection device via the lead wire) of the present embodiment will be described with reference to FIGS. In the relay section of the present embodiment, as shown in FIG. 1, a terminal board 4 is provided outside a pin board 88, and the terminal board 4 has a plurality of jack-type terminals each having one end connected to an inspection device 18. 41 is arranged. On the other hand, a lead wire 15 is connected to the upper end 12 of the probe 1. The tip 152 of the lead wire 15 is removably inserted and fixed to the jack type terminal 41.

The connection between the jack type terminal 41 and the inspection device 18 is made by the lead wire 16 (FIGS. 1 and 10).
On the other hand, a lead wire 15 is attached to the upper end 12 of the probe 1.
Is connected by soldering (FIGS. 1 and 4). As shown in FIG. 10, the leading end of the lead wire 15 is made of a conductor-exposed portion 1 by removing insulators such as coatings and films.
52 is formed. The exposed conductor 152 is inserted into the opening 411 of the jack type terminal 41. Thereby, the probe 1 and the jack type terminal 41 are electrically connected,
Further, it is connected to an inspection device 18 via a lead wire 16.

Also, the jack type terminal 41 is shown in FIGS.
As shown in FIG. 0, a circular opening 411 into which a lead wire can be easily inserted is provided, and the inserted lead wire 15 is elastically gripped by the spring action of the constricted portion 412. Further, the gripping force of the lead wire of the jack type terminal 41 is selected to be a tensile load that allows the lead wire to be easily pulled out manually. Next, the operation and effect of the relay section of this example will be described. In this example, the conductor exposed portion 152 of the lead wire 15 is connected to the jack type terminal 41.
, The tester 18 and the probe 1 are easily electrically connected. In addition, the above lead wire 1
By pulling out the conductor exposed portion 152 of No. 5 from the jack type terminal 41, the detecting portion can be easily separated from the inspection device 18. Therefore, contact and removal between the inspection device 18 and the inspection unit are extremely easy, and replacement of the detection unit accompanying the change of the printed wiring board 7 to be inspected is extremely easy.

Further, in this embodiment, it is only necessary to form the conductor exposed portion 152 at the tip of the lead wire 15, and it is not necessary to attach a special component or the like. Therefore, the lead wire 15
The probe 1 can be easily removed from the pin board 88 while the probe 1 is attached to the probe 1. Therefore, the probe 1 and the contact pins 3 can be removed and reused for a detection unit for another printed wiring board.

As described above, according to the present embodiment, even for a high-density wiring circuit, the probe stylus can be reduced in diameter and can be prevented from being damaged, the guide hole can be easily formed, and the inspection can be performed. An inspection jig for a printed wiring board, which can be easily connected to and detached from a device, and which can reuse probes and contact pins, can be provided.

Embodiment 2 In this embodiment, the structure of the jack type terminal 41 in Embodiment 1 is changed. In this example, as shown in FIG. 11, the jack type terminal 41 is not a cylinder but a groove-shaped opening 41.
One. In addition, a constricted portion 412 having a spring action is provided therein, and the lead wire 15 is elastically gripped. Others are the same as the first embodiment, and the same effects can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view of an inspection jig in a first embodiment.

FIG. 2 is a cross-sectional view around a contact pin and a printed wiring board in a state before inspection according to the first embodiment.

FIG. 3 is a cross-sectional view around a contact pin and a printed wiring board at the time of inspection in the first embodiment.

FIG. 4 is a developed front view of a socket and a stylus in the probe according to the first embodiment.

FIG. 5 is a cross-sectional view of a tip portion of the probe according to the first embodiment.

FIG. 6 is a front view of a contact pin according to the first embodiment.

FIG. 7 is a plan view of a guide plate in the first embodiment.

FIG. 8 is a sectional view taken along line AA of FIG. 7;

FIG. 9 is a perspective view of a terminal board according to the first embodiment.

FIG. 10 is an enlarged view of a connection portion between a lead wire and a jack type terminal in the first embodiment.

FIG. 11 is an enlarged view of a connection portion between a lead wire and a jack type terminal in the second embodiment.

FIG. 12 is an overall explanatory view of an inspection jig in a conventional example.

FIG. 13 is an explanatory view around a probe of an inspection jig in a conventional example.

[Explanation of symbols]

 1. . . Probe, 11. . . Socket, 15. . . Lead wire, 152. . . Exposed conductor, 16. . . Lead wire, 18. . . Inspection device, 2. . . Stylus, 25. . . Tube, 3. . . Contact pin, 31. . . Tip, 4. . . Terminal board, 41. . . 6. Jack type terminal, . . Printed wiring board, 71. . . 75. high-density pitch wiring circuit . . 7. Wiring circuit with normal wiring pitch, . . Guide plate, 85. . . Guide hole, 88. . . Pin board,

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 31/02 G01R 31/00 G01R 1/06-1/073 H05K 3/00

Claims (1)

(57) [Claims] An inspection jig for inspecting a wiring circuit on a printed wiring board based on the presence or absence of electrical continuity, the inspection jig comprising a guide plate, a pin board, and a contact for making contact with the wiring circuit. A probe having a built-in pin and a stylus for contacting the contact pin, wherein the contact pin is mounted on the guide plate so as to be able to advance and retreat, and the stylus is built into the probe so as to be elastically advanceable and retractable. In addition, a terminal board is provided outside the pin board, and a plurality of jack-type terminals having one end connected to a tester are provided on the terminal board.
An inspection jig for a printed wiring board, wherein a lead wire is connected, and a tip of the lead wire is removably inserted and fixed to the jack type terminal.