JPH0333014Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a support structure for a large contact probe used for contact continuity testing of printed circuit boards.

In the case of a contact continuity tester for printed circuit boards, the mounting plate supporting a large number of contact probes is moved relatively close to the printed circuit board, and the tip of each contact probe is connected to a package mounted in large numbers on the printed circuit board. Perform a continuity test with each in contact. Therefore, during testing, it is necessary that the tips of all contact probes come into contact with the package reliably and with a contact area sufficient to flow the current used in the test.

[Conventional technology]

An example of a structure for supporting such a contact probe on a mounting plate is shown as a sectional view in FIG. In the figure, 1 indicates a rigid mounting plate made of an insulator such as a glass epoxy resin laminate or Bakelite, and 2 indicates a contact probe.
The body 3 of the contact probe 2 is mounted on the mounting plate 1.
After drilling a hole 4 having a diameter equal to the diameter of , or a diameter with a slight press-fit allowance, and performing counterboring,
Insert the contact probe 2 into the hole 4, inject adhesive 6 into the counterbore 5, and attach the contact probe 2.
It is used to prevent it from falling out.

In other conventional techniques, hole 3 of mounting plate 1
The contact probe 2 is press-fitted into the hole, and counterbore processing and injection of adhesive material are omitted.

In any of the above-mentioned conventional techniques, the tip 7 of the contact probe 2 is urged to protrude from the body 3 by an unillustrated resilient means built into the body 3 so as to be able to move backward. Therefore, in the printed circuit board contact continuity tester, the contact surfaces 8 of the tips 7 of the contact probes 2 supported in large numbers on the mounting plate 1 due to this structure prevent the mounting plate 1 from moving closer to the printed circuit board. Then, since it comes into contact with the printed circuit board package, a continuity test can be performed.

[Problem that the invention attempts to solve]

In the structure described above, the contact probe 2 is inserted into the hole 3 of the mounting plate 1 and then adhesively treated or press-fitted to position the contact probe 2 and prevent it from coming off.
Therefore, each contact probe 2 is absolutely mechanically fixed to the mounting plate 1. Therefore, if the perpendicularity between the mounting plate 1 and the hole 3 drilled in the mounting plate 1 is incorrect, or if the printed circuit board is warped, the printed circuit board and each contact The contact surface 8 of the probe 2 is
Point contact occurs due to uneven contact. As a result, during the contact continuity test, the accuracy of the test deteriorates and the work efficiency of the test decreases due to increased contact resistance, heat generation at the contact part, lack of smooth operation, etc.
There is a risk of damage to the contact probe or printed circuit board.

When the contact probe is a small needle-like probe, the contact between the probe and the printed circuit board is originally made at the tip of the probe, so the problems caused by uneven contact as described above are relatively less likely to occur. hard. On the other hand, in the case of a large contact probe, the area of the contact surface 8 of the probe is large enough to allow a large current to flow.
When there is uneven contact, the loss of contact area is significant.
Therefore, the above-mentioned problems caused by uneven contact are noticeable in the case of large-sized contact probes.

[Means for solving problems]

The present invention provides a support structure for a large-sized contact probe that eliminates the above-mentioned problems and allows the contact probe to trace the surface of a contact object. A hole with a diameter larger than that is drilled, and an elastic material is interposed between the contact probe inserted into the hole and the peripheral wall of the hole, so that the axis of the contact probe can swing freely. This is achieved by a support structure for a large contact probe, which is characterized by supporting the contact probe in a manner similar to that shown in FIG.

[Effect]

The support structure for the large contact probe described above uses an elastic material interposed between the contact probe and the peripheral wall of the hole in the mounting plate to support the contact probe.
Since the axis of the contact probe is supported so as to be able to swing freely, when the contact probe is in a free state, the object to be contacted and the surface of the contact probe that should be in contact with the object to be contacted may, for some reason, Even when the contact probe is tilted, when it comes into contact with the object to be contacted, the contact probe deforms the elastic body and changes the direction of its axis by itself, causing the contact probe to trace the surface of the object to be contacted. . Therefore, there is no possibility that the function of the contact probe will be impaired due to uneven contact.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a main part of an embodiment of the present invention as a sectional view. Note that the same parts are denoted by the same reference numerals throughout the figures. In the figure, the mounting plate 1 has
A hole 9 having a larger diameter than the diameter of the body 3 of the contact probe 2 and a hole 10 having a larger diameter than the hole 9 are drilled concentrically and passing through the mounting plate 1. The contact probe 2 is inserted into both holes 9 and 10, and the flange 11 of the contact probe 2
There is a slight gap between the mounting plate 1 and the back surface of the mounting plate 1. Since the smaller diameter hole 9 has a larger diameter than the body 3 of the contact probe 2 as described above,
There is also a slight gap between the hole 9 and the contact probe 2 inserted into the hole 9 as described above. In the annular space between the outer peripheral wall of the larger diameter hole 10 and the body 3 of the contact probe 2, two or an appropriate number of rubber O-rings 12 are fitted in a compressed state. Therefore, the contact probe 2 is supported on the mounting plate 1 only by these O-rings 12. Both O-rings 12 elastically support the contact probe 2 in a free state so as to be oriented at the center of the hole 10 and perpendicular to the mounting plate 1, so that the contact probe 2 is not subjected to external force. It is possible to tilt the direction of its own axis A. In addition, when an external force in the axial direction is applied to the contact probe 2 based on the force of moving the mounting plate 1 relatively close to the printed circuit board in a contact continuity test, the O-rings 12 resist this external force and the contact probe This generates a frictional force between the contact probe 2 and the surface of the contact probe 2 that is sufficient to restrain the axial position of the contact probe 2 . Therefore, the external force acting on the contact probe 2 in the axial direction is absorbed by the resilient means (not shown) built into the body 3 to urge the tip 7 to protrude.

In this embodiment, when the mounting plate 1 moves relatively close to the printed circuit board during a contact continuity test of the printed circuit board, the surface of each package of the printed circuit board and the contact probe 2 to be in contact with the package are connected. Because the orientation of the contact surface 8 in the free state is not parallel, even if the contact probe 2 is once in a state of uneven contact with the printed circuit board, the force that moves the mounting plate 1 closer to the printed circuit board as described above is Based on this, the force that presses the contact probe 2 against the printed circuit board is converted into a force that changes the direction of the axis A of the contact probe 2 at the part where the contact probe and the printed circuit board make contact, and therefore the contact probe 2 is attached to the O-ring. While deforming 12, own axis A
By swinging the contact surface 8, the contact surface 8 follows the direction of the package of the printed circuit board, and thus the contact surface 8 traces the surface of the package. In this way, the compliance of the contact probe with respect to the printed circuit board is demonstrated.

Further, another embodiment of the present invention is shown in FIG. 2 as a sectional view of the main part. In this embodiment, after the contact probe 2 is inserted into the holes 9 and 10, a rubber-based filler 13 having elasticity and adhesive properties is inserted between the outer peripheral wall of the hole 10 having a larger diameter and the body 3 of the contact probe 2. The structure is such that the contact probe 2 is supported by the filling material 13 by injecting the filling material 13. Therefore, in this embodiment as well, as in the embodiment shown in FIG. 1, the compliance of the contact probe 2 with respect to the printed circuit board can be exerted to ensure the surface conformation of the contact surface 8 of the contact probe 2 with respect to the printed circuit board. can.

[Effect of idea]

As explained above, according to the present invention, each contact probe supported on the mounting plate has compliance with respect to the object to be contacted, so that each contact probe traces the surface of the object to be contacted. Therefore, good contact can be ensured at all times, and the functions of the contact probe can be fully demonstrated.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a main part showing one embodiment of the support structure of a large contact probe of the present invention, Fig. 2 is a sectional view of a main part showing another embodiment of the present invention, and Fig. 3 is a conventional contact probe. FIG. 1...Mounting plate, 2...Contact probe,
3... Body, 4, 9, 10... Hole, 5... Counterbore, 6... Adhesive, 7... Tip, 8... Contact surface, 11... Flange, 12... O-ring , 13
...Filling material.

Claims (1)

[Scope of utility model registration request] A hole with a diameter larger than the diameter of the body of the contact probe is bored in the mounting plate, and an elastic material is interposed between the peripheral wall and the contact probe hole inserted into the hole, and the contact probe is attached to the contact probe. A support structure for a large contact probe characterized by supporting the shaft so that it can swing freely.