JPH01150861A - Contact probe - Google Patents

Abstract

PURPOSE:To surely execute the conduction of the tip of a contact probe and a substrate and to improve the reliability of an inspection by forming the tip of a plunger to a hemispherical shape or a conical shape. CONSTITUTION:A plunger 1 can move in the longitudinal direction in a housing 2. In this regard, the tip shape of the plunger 1 is formed to a hemispherical shape or a conical shape, and also, on the surface of this hemispherical shape, many projections 3 are formed. As a result, when a contact of the side of a substrate to be inspected comes into contact, while sliding on the surface of the tip of the plunger 1, the projections 3 are brought to self-polishing. Accordingly, a conducting property of the tip can be secured extending over a long period of time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used for circuit inspection before and after mounting.
This invention relates to an improvement in the tip shape of a contact probe having a plunger that moves up and down via a spring in a housing.

[Conventional technology]

As shown in FIG. 2, the tips of conventional contact probes often have sharp edges, which break down the insulating material such as flux formed on the surface of the contact and provide continuity.

[Problem that the invention seeks to solve]

If the tip shape of a conventional contact probe is repeatedly used, dirt such as 7 lux will adhere to the tip, making continuity uncertain and causing errors in test results.The present invention solves these drawbacks and provides a contact probe. The purpose of this is to improve the reliability of inspection by ensuring continuity between the tip of the wire and the substrate.

[Means for solving problems]

The contact probe of the present invention is a contact probe that is used for circuit inspection before and after mounting and has a plunger that moves up and down via a spring in a housing, and the tip of the plunger is hemispherical or conical. characterized by something.

〔Example〕

FIG. 1(α), FIG. 1(b), FIG. 3, and FIG. 4 are diagrams showing one embodiment of the present invention, and each diagram will be described in detail below.

First, FIG. 1 (α) is a side view of a contact probe, which is a plunger 1 provided in engagement with a housing 2. As shown in FIG. Here, the plunger 1 can be moved longitudinally within the housing 2.

The tip of the plunger 1 was shaped into a hemispherical shape, and many protrusions 3 were formed on the surface of the hemispherical shape. When we conducted an inspection using this contact probe, we found that
When the contact on the substrate to be inspected slides on the tip surface of the plunger 1 and comes into contact with it, the protrusion 3 is self-polished. For this reason, the conductivity of the contact point is stable over a long period of time.

FIG. 1(b) is the same as FIG. 1(α) described above except that the tip of the plunger 1 has a conical shape.

In this case as well, the same effect as in FIG. 1 (α) was obtained. Furthermore, this conical shape was particularly effective when the pitch of the contact points was small.

In FIG. 3, the protrusion 3 described above is replaced by a spiral 4. The tip of the plunger 1 has a conical shape, and a spiral groove is formed.

In addition, FIG. 4 shows the shape of the tip of the plunger 1 as a small staircase 5.
are stacked in order.

As mentioned above, in the Funtact probe of this embodiment, the tip of the plunger is hemispherical or conical, so even if there is dirt such as flux on the contact part of the board to be inspected, the ion,
It was able to withstand use approximately 00 times. This has an extremely superior effect compared to the conventional method of about 1000 times.

〔Effect of the invention〕

In the present invention, as described above, by making the tip of the plunger semispherical or conical, it is possible to promote self-polishing of the tip and ensure electrical conductivity of the tip for a long period of time. In addition, when there is dirt such as 7 lux on the substrate, the contact resistance of conventional contact probes increases after about 1000 times and the contact probe becomes unusable, requiring cleaning by brushing or replacing, but the contact probe of the present invention According to the above, no increase in resistance is observed even after use about 10QOOO times, and the lifespan is improved.

[Brief explanation of the drawing]

FIG. 1 <a> is a side view showing one embodiment of the contact probe according to the present invention, and FIG. 2 is a side view showing a conventional contact probe; FIG. 3 is a side view of an embodiment of the contact probe of the present invention in which a spiral shape is provided instead of a protrusion; FIG. 4 is a side view showing a conventional contact probe.
The figure is a side view of one embodiment of the contact probe of the present invention in which a step shape is provided instead of a protrusion. 1...Plunger 2...Housing 3...Protrusion 4...Spiral 5...・・・・・・Small stairs and above Applicant Seifu Ebson Co., Ltd. agent Patent attorney Mogamiji (and 1 other person) l' \Mi1.7 Figure 1 (a') Figure 1 (b') Figure 2 Figure 4

Claims (1)

[Claims] A contact probe that is used for circuit inspection before and after mounting and has a plunger that moves up and down via a spring in a housing, wherein the tip of the plunger is semispherical or conical. .