JPH0351766A - Conductive contact element - Google Patents

Abstract

PURPOSE:To eliminate contact inferiority by rotating a contact point by bringing the projection provided to the side wall of a plunger into engagement with the spiral slot of a receptacle and allowing the projection to slide along the slot when the plunger slides. CONSTITUTION:A spiral slot 6 is provided to the wall surface of a receptacle 2 in the longitudinal direction thereof and the projection 7 of a plunger 4 is engaged with the slot 6 and one end of the plunger 4 is pressed by a spring 5. When the plunger 4 slides in the cylinder of the receptacle 2, the projection 7 slides along the slot 6 and, therefore, a contact point 3 is elastically brought into contact with an object under rotation and no contact inferiority is generated. Further, by making the shape of the contact point columnar, a good contact state is obtained even in such a case that contact inferiority is generated in a conventional conductive contact element and the object is not damaged. Therefore, the inspection efficiency of a printed circuit board is enhanced to a large extent.

Description

[Detailed Description of the Invention] [Summary] Regarding conductive contacts, particularly conductive contacts used for inspecting contact objects such as printed circuit boards, the present invention relates to conductive contacts that can reliably make contact with the contact portion of the contact object and that , a cylindrical receptacle, and a cylindrical receptacle, which is shorter than the length of the receptacle, is slidably provided inside the receptacle, and is provided with a cylindrical contact protruding from the receptacle for the purpose of not damaging the contact. A column-shaped plunger supported so that the end thereof does not come out of the receptacle, and a contact point provided inside the receptacle and provided at one end of the plunger so as to always protrude from the end of the receptacle. a spring for pressing the other end of the plunger; a spiral elongated hole is provided in the longitudinal direction of the wall surface of the receptacle; a protrusion is provided on the side wall of the plunger; When sliding inside the cylinder, the protrusion is configured to slide while being fitted into the elongated hole.

[Industrial application field]

The present invention relates to a conductive contact, and particularly to improvement of the contact state between a contact point of a conductive contact and a contact portion of a contact object.

In the testing process of electronic components such as semiconductor devices,
A conductive contact to which contact pressure is applied by a spring is used.

This conductive contact consists of a plunger, a receptacle and a spring.

Normally, a cylindrical plunger slides within a cylindrical receptacle, and the plunger is always pressurized by a pressure spring in the direction of protruding out of the receptacle.

Therefore, the contact point at the tip of the plunger comes into elastic contact with a contacting object, such as a terminal provided on a printed board, to establish electrical continuity.

If there is a problem in the contact between the contact at the tip of the plunger and the contact part of the contact object, it may be due to poor conduction at the contact part.
Or, it becomes unclear whether the contact object itself is defective.

Therefore, there is a need for the development of a conductive contact that can reliably make contact between the contact point at the tip of the plunger and the contact portion of the object to be contacted.

[Conventional technology]

FIG. 4 is a sectional view illustrating a conventional conductive contact, FIG. 5 is an enlarged view of the X section in FIG. 4, and FIG. 6 is a side view of the conventional conductive contact during operation.

In FIG. 4, a columnar plunger 4 is housed in a cylindrical receptacle 2, and one end of the plunger 4 protrudes thinly from one end of the receptacle 2, with a contact point at the tip. 3 is provided.

Further, the other end of the plunger 4 is elastically supported by a spring 5 interposed between it and the other end of the receptacle 2 in a direction in which it is always pushed out.

On the other hand, the shape of the contact point 3 provided at the tip of the plunger 4 may be, for example, a cylindrical shape as shown in (a) of FIG. 5, or a conical shape as shown in (b) of FIG. (c)
As shown in the figure, it may be a crown-cut type.

As shown in FIG. 6, this conductive contact l is
The receptacle 2 is supported vertically so that the contact point 3 faces upward, and the contact part 10 of the object to be contacted 9 is turned downward and makes elastic contact with the contact point 3 to establish electrical conduction.

In this way, for example, in the case of a printed board inspection device, a plurality of these conductive contacts l are installed and brought into elastic contact with the pad portion or contact portion provided on the printed board to be inspected all at once. , inspect circuit patterns, etc.

However, the contact between the contact point 3 and the contact portion 10 is, for example, 30
This is contact due to static pressure of g weight.

Therefore, an oxide film may be formed on the surface of the contact portion 10,
If foreign matter such as dust is attached, reliable contact may not be possible from time to time.

In addition, the shapes (B) and (C) of the contact 3 are devised to ensure good conduction when the contact 3 and the contact portion 10 of the contact object 9 come into elastic contact. In this case, the contact portion 10 of the contact object 9 may be damaged and destroyed if repeated multiple times.

[Problem to be solved by the invention]

As mentioned above, conventional conductive contacts have the problem of not being able to make reliable contact with objects such as printed circuit boards due to the formation of an oxide film or the adhesion of foreign matter such as dust. .

Further, in order to improve the contact, if the shape of the contact point of the conductive contactor is made into a conical shape or a crown-cut shape, the contact performance is improved, but there is a problem of damaging the contact portion of the object to be contacted.

The purpose of the present invention is to provide a conductive contact that can reliably contact even if an oxide film is formed or foreign matter adheres to the contact part of the contact object, and does not damage the contact part of the contact object. It is said that

[Means to solve the problem]

The above-mentioned problems include a cylindrical receptacle and one end portion that is shorter than the length of the receptacle, is slidably provided inside the receptacle, and is provided such that a cylindrical contact protrudes. The columnar plunger is supported so that it does not come out of the receptacle, and the contact point provided inside the receptacle and provided at one end of the plunger always protrudes from the end of the receptacle. a spring that presses the other end of the plunger, in the longitudinal direction of the wall surface of the receptacle;
A spiral elongated hole is provided, a protrusion is provided on the side wall of the plunger, and the plunger is configured to slide with the protrusion fitted into the elongated hole when the plunger slides inside the cylinder of the receptacle. Solved by conductive contacts.

[For production]

In the present invention, a columnar plunger slides inside a cylindrical receptacle without being pushed by a spring, and a contact point protruding from the tip of the plunger causes the plunger to bounce against the contact portion of a contact object such as a printed board. Instead of a conventional conductive contact, a spiral elongated hole is bored in the wall of the receptacle, and a protrusion is provided on the wall of the plunger that smoothly fits into the elongated hole.

In this way, when the contact point is pressed against the contact portion of the object to be contacted and the receptacle is pushed firmly, the plunger does not slide inside the receptacle but rotates.

That is, the contact contacts the contact portion of the object to be contacted without rotating, and rubs the surface of the contact portion, so that even if foreign matter adheres to the surface of the contact portion, it is wiped off.

On the other hand, the shape of the tip of the contact point is cylindrical so that even if the contact point rubs against the contact part of the object to be contacted, it will not cause any damage.

Thus, according to the conductive contactor of the present invention, stable contact can be achieved without damaging the contact portion of the contact target such as a printed board.

[Embodiment] FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a sectional view of FIG. 1, and FIG. 3 is a side view of FIG. 1 during operation.

In FIG. 1, a conductive contact 1 according to the present invention has a receptacle 2 having an outer diameter of 4 smφ, an inner diameter of 3+*mφ, and a length of 30a.
n brass tube was used.

In addition, the plunger 4 is made of brass and has a diameter of 3IIIlφ.
A cylindrical contact point 3 with a diameter of 2IllIφ and a length of 3IIIm was provided at one end of a round bar with a length of 15 mm via a protruding rod 8 with a diameter of Lmmφ and a length of lO.

This contact 3 was plated with Au.

A spiral long hole 6 having a width of 0.5 mm and a length of 12 mm is bored in the wall of the receptacle 2, and a projection 7 that smoothly fits into the long hole 6 is fixed to the wall of the plunger 4.

A coiled spring 5 is installed in the receptacle 2 so that the plunger 4, which is slid and pushed into the receptacle 2, returns spontaneously when the pressure is released.

In this manner, when the plunger 4 is pushed into the receptacle 2, the plunger 4 and the contact point 3 connected thereto do not rotate and come into elastic contact with the contact portion 10 of the contact object 9, as shown in FIG. The functions of the conductive contact 1 are exhibited.

Performance comparisons were made using a printed board inspection device with 25 contact parts, using 25 conventional conductive contacts 1 and 25 conductive contacts 1 manufactured according to this example.

As a result, out of a total of 1,000 contact parts, there were 6 contact failures due to the conventional conductive contact 1.

In contrast, there were no contact failures caused by the conductive contact 1 of the present invention.

Various modifications can be made to the shapes and dimensions of the receptacle, plunger, contacts, etc. that constitute the conductive contact implemented here.

Furthermore, the conductive contact of the present invention is not limited to large-scale applications such as printed board inspection equipment that supports and inspects multiple conductive contacts at predetermined positions as described in Nee. For example, holding and operating a single conductive contact,
It can also be applied to manual usage.

〔Effect of the invention〕

As described above, whereas conventional conductive contacts cause poor contact or damage the contact portion of the object to be contacted, the present invention provides 2! ! According to the electric contact, when the contact point is applied to the contact part of the object to be contacted and the receptacle is firmly pushed in, the receptacle does not rotate at the contact point and comes into elastic contact with the contact part of the object to be contacted, so there is no possibility of contact failure.

Furthermore, by making the contact point cylindrical in shape, it is possible to obtain a good contact state without damaging the contact portion of the object to be contacted, whereas conventional conductive contacts would result in poor contact.

Therefore, the conductive contact according to the present invention can contribute to a significant improvement in the efficiency of inspecting, for example, printed boards.

[Brief explanation of drawings]

Fig. 1 is a perspective view of an embodiment of the present invention, Fig. 2 is a sectional view of Fig. 1, Fig. 3 is a side view of Fig. 1 during operation, and Fig. 4 explains a conventional conductive contact. 5 is an enlarged view of the X section in FIG. 4, and FIG. 6 is a side view of a conventional conductive contact during operation. In the figure, ① is a conductive contact, 3 is a contact, 5 is a spring, and 7 is a protrusion. 2 is a receptacle, 4 is a plunger, 6 is a long hole, Fig. 1 Fig. 3 Fig. 2

Claims (1)

[Scope of Claims] A cylindrical receptacle (2); and a cylindrical contact (3) that is shorter than the length of the receptacle (2) and is slidably provided inside the receptacle (2). a columnar plunger (4) whose one end protruding from the receptacle (2) is supported so that it does not come off from the receptacle (2); The contact (3) provided at one end of the receptacle (
said plunger (4) so that it always protrudes from the end of said plunger (4).
), a spiral elongated hole (6) is provided in the longitudinal direction of the wall surface of the receptacle (2), and a spiral elongated hole (6) is provided in the side wall of the plunger (4). A protrusion (7) is provided, and when the plunger (4) slides inside the cylinder of the receptacle (2), the protrusion (7) slides while being fitted into the elongated hole (6). A conductive contact featuring: