JPH11243262A - Substrate having pattern for front and rear discrimination and inspection device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage to contact pins and the like, which is accompanied by the reverse placement of a substrate, using the substrate having a pattern for front and rear discrimination, by a method wherein the substrate has conductive lands which are respectively made contact with the plurality of the conductive parts of an inspection device, and the conductive pattern for connecting both lands with each other. SOLUTION: A substrate 20 has two lands 20a and 20b and a pattern 20c for connecting both lands 20a and 20b with each other on the rear of the substrate 20. The lands 20a and 20b are formed of a conductive member, and holes 20d and 20e for fitting into reference positioning pins 7 are respectively provided in the central parts of the lands 20a and 20b. That is, the holes 20d and 20e are provided in the state corresponding to reference holes 13, and the size between the holes 20d and 20e is formed in such a way as to coincide with the size between the two positioning pins 7. Moreover, the pattern 20c also is formed of a conductive member. As a result, damage to the contact part of the substrate due to making an inspection jig descend by mistake can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate having a pattern for discriminating front and back surfaces and an inspection device therefor, and more particularly, to performing a predetermined measurement by bringing a contact portion such as a contact probe into contact with a contacted portion such as a conductive portion of the substrate. It is useful when applied to an in-circuit tester or the like.

[0002]

2. Description of the Related Art An in-circuit test and a function test are performed on a printed circuit board on which electronic components such as ICs are mounted. An in-circuit test is a test to check whether each electronic component, for example, resistance, inductance and capacitance, has a required characteristic. A function test is a test in which an electric circuit formed on a mounting board has a required input / output characteristic. This is a test to determine whether or not the user has

In order to perform an in-circuit test or a function test, a fixture-type inspection device, for example, an in-circuit tester is used. This in-circuit tester includes an upper fixture 1 and a lower fixture 2 as shown in FIG.

An upper fixture 1 serving as an inspection jig has positioning holes 3 at four corners and a large number (1000) on the lower surface.
(Approximately 2,000 contacts), which is a contact probe 4 and moves up and down by a lifting mechanism (not shown). The lower fixture 2 serving as a base plate has positioning pins 5 at four corners and has a large number (1000-2
(Approximately 000) contact probes 6 and two board positioning pins 7 and are fixed to a base 8 of the apparatus. Here, the contact probes 4 and 6 are provided by the number corresponding to the positions corresponding to the inspection points described later.

FIG. 4 shows an inspection state in the circuit tester. As shown in FIG.
An electronic component (IC or the like) 12 is mounted on a substrate 11 using cream solder or a solder bath.
Reference holes 13 are formed.

At the time of inspection using such an inspection apparatus, first, the position of the mounting substrate 10 is determined with the substrate positioning pins 7 penetrating through the reference holes 13. Next, the upper fixture 1 is lowered while positioning so that the positioning pins 5 are fitted into the positioning holes 3. Thus, the mounting substrate 10
The tip of the contact probe 4 is brought into contact with the test land, which is the inspection point on the upper surface of the mounting substrate 10, while the tip of the contact probe 6 is brought into contact with the test land, which is the inspection point on the lower surface of the mounting board 10. In such a contact state, various tests are performed by applying a voltage to a predetermined electronic component through the respective contact probes 4 and 6 and supplying a current. After the test is completed, the upper fixture 1 is raised and the mounting substrate 10 is removed.

[0007] In order to perform the above inspection properly, it is necessary to always bring the contact probes 4 and 6 into contact with the inspection point at a predetermined pressure. This is because electrical characteristics such as impedance vary depending on the contact pressure.

Here, the upper fixture 1 is normally moved up and down by using an air cylinder (not shown) as a drive source. That is, as shown in FIGS. 3 and 4,
This is performed by linearly moving a rod 9 having a lower end surface fixed to the upper surface of the upper fixture 1 in a vertical direction. Therefore, the contact pressure is determined by the air pressure supplied to the air cylinder.

[0009]

When the upper fixture 1 is lowered while the mounting substrate 10 to be inspected is placed on the lower fixture 2 with its front and back reversed in the inspection apparatus as described above, the contact probes 4 and 6 are moved. It causes inconvenience such as breakage. In order to avoid such inconvenience, a pin for preventing reverse placement is provided in addition to the reference positioning pins 7 provided at two points, so that when the reverse placement is performed, this pin contacts the back surface of the mounting board 10. However, in this case, the same inconvenience occurs when the upper fixture 1 is lowered by operating the drive switch of the inspection apparatus.

In view of the above prior art, the present invention provides a substrate having a front / back discrimination pattern that can contribute to reliably detecting the reverse of a substrate to be inspected, and using this substrate to make a determination. It is an object of the present invention to provide an inspection apparatus for a substrate that can prevent damage to contact pins and the like due to reverse placement.

[0011]

The structure of the present invention that achieves the above object has the following features.

1) When the front and back sides of the inspection apparatus are properly disposed, the inspection apparatus has conductive lands that respectively contact two conductive portions of the inspection apparatus and a conductive pattern that connects between the lands.

2) A substrate to be inspected is placed on a base plate which is a flat plate member, and an inspection jig which is a flat plate member having a contact portion such as a contact probe is lowered toward the base plate. The contact portion is configured to be brought into contact with the inspection point with a predetermined pressure, and in the substrate inspection apparatus for inspecting the substrate in such a state of contact, the substrate having the front / back discrimination pattern described in 1) above is preferably used. It has two conductive portions, such as positioning pins, which are configured so as to secure an electrical connection state by being brought into contact with the land as it descends and to be able to connect between the lands via the pattern of the substrate. The apparatus can be driven to lower the inspection jig on condition that these two conductive parts are connected.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a plan view of a substrate according to an embodiment of the present invention as viewed from the back. As shown in the figure, the substrate 20 has two lands 20a and 20b and a pattern 20c connecting between the lands 20a and 20b on the back surface thereof. The lands 20a and 20b are formed of a conductive member, and have holes 20d and 20e at the center thereof for fitting into the reference positioning pins 7 (see FIGS. 3 and 4). That is, the holes 20d and 20e are provided corresponding to the reference holes 13 (see FIG. 4), and the size between them is formed so as to match the size between the two reference positioning pins 7. The pattern 20c is also formed of a conductive member.

FIG. 2 is a sectional view showing a main part of the inspection apparatus according to the embodiment of the present invention. As shown in the figure, the reference positioning pins 7 are formed of a conductive member, and are connected to the inspection circuit 22, respectively. Switch 2
Reference numeral 1 denotes a switch for driving the inspection apparatus, which is also connected to the inspection circuit 22. The switch 21 drives the air cylinder of the inspection apparatus to lower the upper fixture 1 by operating the switch 21. In order to lower the upper fixture 1, it is necessary that the reference positioning pins 7 are short-circuited. Become.

The substrate 20 is provided with the reference hole 13 in the lower fixture 2.
Is placed and positioned on the lower fixture 2 by inserting it into the reference positioning pin 7. If the front and back sides are normal, the lands 20 a and 20 b contact the reference positioning pin 7. The positioning pins 7 are short-circuited by the pattern 20c. On the other hand, when the front and back are reversed, the reference positioning pins 7 are not short-circuited, and therefore, even if the switch 21 is operated, the upper fixture 1 cannot be lowered. That is, in this case, the operation of the upper fixture 1 is interlocked. In the figure, reference numeral 7a denotes a spring fitted on the reference positioning pin 7.

According to the above embodiment, it is possible to determine whether or not the mounted state is proper only by mounting the substrate 20 to be inspected on the lower fixture 2 for inspection. Only in the case of, the upper fixture 1 can be lowered toward the substrate 20 by operating the switch 21.

In the above embodiment, the reference locating pin 7 is used to short-circuit the lands 20a and 20b. However, the present invention is not limited to this. Conductive pins that contact the lands 20a and 20b may be provided on the lower fixture 2 side. Further, the inspection target may be, for example, a substrate itself such as a printed wiring board before electronic components are mounted.

[0020]

According to the present invention, as specifically described above with reference to the embodiments, the substrate to be inspected is simply mounted on the base plate for inspection, and whether or not the mounted state is proper. Can be determined, and only if it is appropriate,
Since the inspection device can be driven,
It is possible to prevent the contact portion from being damaged by accidentally lowering the inspection jig.

[Brief description of the drawings]

FIG. 1 is a plan view of a mounting board according to an embodiment of the present invention as viewed from the back surface.

FIG. 2 is a cross-sectional view extracting and showing a main part of the inspection apparatus according to the embodiment of the present invention.

FIG. 3 is a perspective view showing an in-circuit tester.

FIG. 4 is a perspective view showing the in-circuit tester in a state at the time of inspection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper fixture 2 Lower fixture 4 Contact probe 20 Substrate 20a, 20b Land 20c Pattern 21 Switch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H05K 3/00 G01R 31/28 K

Claims (2)

[Claims] 1. An inspection apparatus, comprising: a conductive land that is in contact with two conductive portions of the inspection apparatus when the front and back sides are properly arranged; and a conductive pattern that connects the two lands. A substrate having a pattern for front / back discrimination. 2. The method according to claim 1, wherein a substrate to be inspected is placed on a base plate as a flat plate member, and an inspection jig as a flat plate member having a contact portion such as a contact probe is lowered toward the base plate. A board inspection apparatus configured to contact a contact portion with an inspection point at a predetermined pressure, and performing an inspection of the board in such a state of contact, wherein the substrate having the front / back discrimination pattern according to claim 1 is provided. It has two conductive portions, such as positioning pins, which are configured so as to secure an electrical connection state by being brought into contact with the land as it descends and to be able to connect between the lands via the pattern of the substrate. Characterized in that the apparatus can be driven to lower the inspection jig on condition that these two conductive parts are connected. Board inspection apparatus having over emissions.