JPS60227175A - Testing method of printed board - Google Patents

Abstract

PURPOSE:To test the continuity of the printed board by simple and easy contacting without using any adapter by fitting conductive balls in through-holes of the board to be tested and bringing them into contact with conductor lands of a testing jig. CONSTITUTION:Conductive balls 15 are fitted in through-holes of the printed board 1 to be tested and brought into contact with rectangular conductor lands 41 centered around grid points 10 on the reverse surface of the testing jig 4. Then, the continuity of the printed board is tested by the easy and simple contacting without using any adapter, etc., regardless of whether the through holes are a on-grid or off-grid type.

Description

DETAILED DESCRIPTION OF THE INVENTION +8) Technical Field of the Invention The present invention relates to a method for testing printed circuit boards, and in particular to a new method for testing continuity.

fb) Conventional technology and problems With the amazing progress in electronic technology, a huge amount of printed circuit boards are being used, and as printed circuit boards become more diverse and available in a wide variety of products, they are also becoming more dense and multi-layered. Advanced printed circuit boards have come into widespread use.

FIG. 1 illustrates a partial plan view of Print@1.
1 is a circuit pattern, 12 is a through hole, and the printed board 1 itself is an insulator made of an organic resin board or a ceramic board. In addition, the positions of the through holes 12 are generally standardized, and the positions of the through holes 12 are generally standardized, and the positions of the through holes 12 are arranged at grid points, that is, grid points 10.
A through hole 12 is arranged on the board (referred to as an on-grid printed board), and the interval between grid points is set to 2.54 mm or 1.27 tm.

Such printed boards are subjected to various inspections during production, and the continuity test (checking for disconnections and short circuits) of the circuit pattern is performed by touching contact pins to the through holes, and the testing method is as follows: It is roughly as follows.

That is, as shown in FIG. 2, the test jig 2 is placed facing the pudding 1-board 1 to be tested, and the contact pin 21 is placed at a position facing the through ball 12 (lattice point 10). In this method, a continuity test is performed by holding the test jig 2 upright, bringing it into contact with the through hole 12, and connecting the contact pin 21 with a terminal (not shown) of a tester on the opposite side of the test jig 2.

However, due to the increasing density of printed boards, types of printed boards (off-grid printed boards) in which it is difficult to arrange through holes 12 at grid points are also being manufactured. Even if the test jig 2 in which the pins 21 are arranged is used, the pins 21 cannot be brought into contact with the through holes 12. Therefore, at that time, as shown in FIG. 3, an adapter 3 is interposed between the print 1-board 1 and the test jig 2, and the contact pin 21 is corrected diagonally to form a through hole 12 degrees that is not at the grid point. The contact pin 21 is designed to be in contact with the contact pin 21.

However, in this method of interposing the adapter 3, it is necessary to create each type of adapter that matches the type of printer 1-board.

(C) Purpose of the Invention The present invention does not require such an adapter;
This paper proposes a continuity test method that allows easy contact.

(dl Structure of the Invention The purpose is to arrange conductive lands including one lattice point of the opposing printed board to be tested on the opposite surface of the test jig connected to the testing machine from the main surface, and This is achieved by a printed board testing method in which a conductive ball is fitted into a through hole of the printed board, and the conductive ball and the conductive land are brought into contact to perform a continuity test.

In addition, on the opposite side of the test jig that is connected to the tester from the main surface, hang a conductor ball with a wire from a position corresponding to the lattice point of the opposing printed board under test, and hang the conductor ball on the printed board under test. This can also be achieved by a printed board testing method in which a continuity test is performed by inserting the board into a through hole in the board.

te+ Example of invention Examples will be described in detail below with reference to five drawings.

FIG. 4 (al shows a schematic sectional view of a test method according to an embodiment of the present invention, and FIG. The figure shows a plan view (viewed from the surface).

As shown in the figure, through hole 1 of printed board 1 to be tested
2. Fit the conductor ball 15 onto the printed board l, and bring the test jig 4 according to the present invention into contact with the printed board l, and bring the conductor ball 15 into contact with the conductor land 41 of the test jig 4. As shown in the partial plan view of FIG. Even when the through holes 12' are not located at lattice points, as in the case of a grid printed board, the conductor ball 15 and the conductive land 41 can be brought into contact with each other.Of course, it can also be used for an on-grid printed board.

In this case, for example, a conductor ball 15 of approximately 1.5+nφ is used for a through hole 12 of l mu φ. In addition, in order to fit the conductor ball 15 into the through hole,
The printed board 1 is brought into a state where vacuum suction is applied from the back side (see FIG. 5 below), and the conductor balls 15 are rolled on the front side. Then, all through balls are filled with conductor balls. Furthermore, if the conductor ball is tested while being vacuumed, sufficient contact can be made and the reliability of the test can be increased.

Furthermore, if the conductor land has spring properties, better contact can be maintained.

Next, FIG. 5 shows a schematic sectional view of another embodiment according to the present invention, and the test jig 5 of this embodiment has a conductor ball 15 suspended from a lattice point 10 by a wire. Insert it into the through hole 12 of the printed board to be tested,
Perform a continuity test. Then, through hole 12.1
Regardless of whether 2' is at the grid point 10 or not, it can be connected to the test machine through the test fixture.

To fit the conductor balls 15 into the through holes, the printed board 1 is placed in the vacuum suction storage box 6 as shown in the figure, and the test jig 5 is applied to the printed board 1 while vacuum is being suctioned from the back side of the printed board. Furthermore, if a magnet N is provided on the back surface and the conductor ball 5 is made of a magnetic material to apply magnetic force, the contact force will be further strengthened. Furthermore, in this example, it is convenient to sandwich a matrix-shaped frame 7 between the test jig 5 and the printed board 1, so that the conductor balls do not come into contact with each other.

(f) Effects of the Invention As is clear from the above explanation, according to the present invention, continuity tests can be performed on both on-grid printed boards and off-grid printed boards without using an adapter. In addition, there is no need to worry about contact displacement, making the test highly reliable.

Furthermore, the embodiment described in FIG. 4 can be used as a versatile test jig regardless of the type of printed board (different types of conductive patterns).

[Brief explanation of the drawing]

FIG. 1 is a partial plan view of a printed board, FIGS. 2 and 3 are schematic cross-sectional views showing a conventional test method, and FIG. 4 (al is a schematic cross-sectional view showing a test method according to an embodiment of the present invention) , FIG. 4(b) is a partial plan view of the test jig shown in FIG.
The figure is a schematic sectional view showing a test method according to another embodiment of the present invention. In the figure, 1 is a printed board and 2 is a conventional test jig. 3 is an adapter, and 4.5 is a test jig according to the present invention. 6 is a storage box for vacuum suction, and 7 is a matrix-shaped frame. 10 is a lattice point, 11 is a conductor pattern, 12 is a through hole, 15 is a conductor ball, 41 is a conductor land, and N is a magnet. Figure 1 Figure 182 Figure 3 Figure 4 Figure 5 Norito Natsu (

Claims (2)

[Claims] (1) - On the opposite side of the test jig that is connected to the tester from the main surface, arrange conductor lands that include one lattice point of the opposing printed board under test, and connect them to the through holes of one printed board under test. A method for testing a printed circuit board, characterized in that a conductor ball is inserted and the conductor pole and the conductor land are brought into contact with each other to control the conductor IN test. (2) - On the opposite side of the test jig connected to the testing machine from the main surface, hang a conductor pole with a wire from a position corresponding to the lattice point of the opposing printed board under test, and place the conductor ball on the opposite side of the test jig. A method for testing a printed board, characterized in that a continuity test is performed by inserting the printed board into a through hole of the printed board.