JP4149196B2 - Spring contact probe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spring contact probe in which a through hole is provided on a closed end side and dust or the like does not enter through a through hole in a conductive tube in which a conductive thin film can be appropriately plated on an inner peripheral wall. It is.
[0002]
[Prior art]
An example of the structure of a conventional spring contact probe will be described with reference to FIG . FIG. 3 is a longitudinal sectional view of an example of a conventional spring contact probe.
[0003]
In FIG. 3 , one end of the conductive tube 10 is closed and the other end is opened, and the spring 12 and the large diameter portion 14 a of the plunger 14 are inserted from this opening. Then, the opening is squeezed by caulking, and the plunger 14 is configured to be slidable in the axial direction, and the contact portion 14b protrudes without the large diameter portion 14a coming out. Here, the spring 12 is contracted and elastically biases the plunger 14 in the protruding direction. The tip of the abutting portion 14b of the plunger 14 and the tip of the closed end of the conductive tube 10 are, for example, a tip so as to contact the device under test and the connection electrode of the substrate to ensure electrical conduction. It is configured in a cross shape. Further, on the closed end side of the conductive tube 10, through holes 16 and 18 are formed on the side walls and the axis of the closed end, respectively.
[0004]
Incidentally, the electrical continuity between the conductive tube 10 and the plunger 14 is achieved by the large diameter portion 14 a of the plunger 14 slidingly contacting the inner peripheral wall of the conductive tube 10. Therefore, for the purpose of reducing the resistance value in electrical conduction, the inner peripheral wall in the conductive tube 10 and the outer peripheral wall of the plunger 14 are plated with a conductive thin film such as gold plating. The conductive thin film may be plated by either electrolytic plating or electroless plating.
[0005]
As an example, the conductive tube 10 has an inner diameter of 0.4 mm and a length of 2.5 mm, and the inner diameter is extremely thin with respect to the length. Therefore, by providing the through holes 16 and 18 on the closed end side of the conductive tube 10, the plating solution sufficiently penetrates to the inner side of the closed end side in the conductive tube 10 when plating the conductive thin film. In addition, the cleaning solution for cleaning the plating solution that has penetrated to the back can also penetrate sufficiently, and the inner peripheral wall in the conductive tube 10 can be appropriately plated with the conductive thin film. Therefore, the yield in the manufacturing process is improved.
[0006]
[Problems to be solved by the invention]
However, in the conductive tube 10 having the above-described conventional structure, there is a possibility that dust or the like may enter the conductive tube 10 through the through holes 16 and 18 formed on the closed end side. The dust that has entered the conductive tube 10 adheres to the inner peripheral wall, causing a problem of increasing the contact resistance between the conductive tube 10 and the plunger 14. Further, due to the adhesion of dust to the inner peripheral wall of the conductive tube 10, the sliding resistance of the plunger 14 with respect to the conductive tube 10 also increases, resulting in malfunction. Further, the sliding contact portion between the conductive tube 10 and the plunger 14 is worn, and this wear increases the contact resistance and impairs the durability.
[0007]
The present invention has been made in view of the circumstances of the prior art as described above, and a plunger is disposed in a conductive tube that can be appropriately plated with a conductive thin film on the inner peripheral wall with a through hole. An object of the present invention is to provide a spring contact probe that does not allow dust or the like to enter the side through a through hole.
[0008]
[Means for Solving the Problems]
In order to achieve such an object, the spring contact probe of the present invention is capable of sliding the plunger in the axial direction in a conductive tube having a through hole on the closed end side and a conductive thin film plated on the inner peripheral wall. And a contact portion protruding so as not to come out, and a spring is contracted in the conductive tube so as to elastically urge the plunger in the protruding direction, and the plunger is an inner peripheral wall of the conductive tube. In the spring contact probe that slides in contact with the spring to make electrical conduction, a blocking member that fits and contacts the inner peripheral wall of the conductive tube is disposed between the closed end of the conductive tube and the spring, and the closed The member is elastically biased toward the closed end by the spring, and the closed member blocks communication between the side where the plunger is disposed in the through hole and the conductive tube. It is configured to.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIG. 1A is a longitudinal sectional view of a first embodiment of the spring contact probe of the present invention, and FIG. 1B is an external perspective view of a cup-shaped closing member. In FIG. 1A , the same or equivalent members as in FIG.
[0010]
In a first embodiment of a spring contact probe of the present invention shown in FIG. 1, which differ in the prior art shown in FIG. 3, obstruction of cup-shaped with the closed end side of the conductive tube 10 is fitted abuts against the inner peripheral wall The member 20 is inserted and arranged. The closure member 20 is in close contact with the inner circumferential wall of the conductive tube 10, and cuts off the communication between the plunger 14 side of the section from the position where the closing member 20 is arranged in the through hole 16, 18 side and the conductive tube 10. The through holes 16 and 18 are substantially closed. The closing member 20 is always elastically biased toward the closing end by the spring 12 and is not displaced. In addition, one end of the spring 12 is inserted into the cup shape of the closing member 20, and the position of the one end of the spring 12 is stabilized.
[0011]
In such a configuration, the plating solution and the cleaning solution sufficiently flow into the conductive tube 10 through the through holes 16 and 18 formed on the closed end side, and an appropriate conductive thin film is plated on the inner peripheral wall. After the spring contact probe of the present invention is assembled, the through holes 16 and 18 are substantially closed by the closing member 20, and the plunger 14 in the conductive tube 10 is in sliding contact with the through holes 16 and 18. Dust and the like do not enter the part. Therefore, problems such as an increase in contact resistance and an increase in sliding resistance due to dust and the like, and further deterioration in durability are not caused. As a result, there is no problem due to the through holes 16 and 18 being formed, and the contact resistance is stabilized at a small value so that the conductive thin film can be appropriately plated.
[0012]
FIG. 2 shows a second embodiment of the present invention. FIG. 2A is a partial longitudinal sectional view of a second embodiment of the spring contact probe of the present invention, and FIG. 2B is an external perspective view of a cylindrical occlusion member.
[0013]
The second embodiment of FIG. 2 is different from the first embodiment of FIG. 1 in that it is inserted on the closed end side of the conductive tube 10 and is fitted and abutted on the inner peripheral wall to form a closed member 22 having a cylindrical shape. Is in the arrangement. The columnar blocking member 22 blocks communication between the through holes 16 and 18 and the portion closer to the plunger 14 than the blocking member 22 in the conductive tube 10.
[0014]
In the structure of the second embodiment, the shape of the closing member 22 is extremely simple, and the parts can be manufactured relatively easily even if the inner diameter of the conductive tube 10 is reduced. And the effect similar to 1st Example is obtained.
[0015]
【The invention's effect】
As described above, since the spring contact probe of the present invention is configured, the following advantageous effects can be obtained.
[0016]
In the spring contact probe according to claim 1, the conductive thin film is appropriately plated on the inner peripheral wall of the conductive tube by the through hole on the closed end side of the conductive tube. After assembly , the through-hole is substantially blocked since the communication between the through-hole and the plunger in the conductive tube is blocked by the closing member that fits and contacts the inner peripheral wall of the conductive tube. In addition, there is no possibility that dust or the like enters the side where the plunger in the conductive tube is disposed through the through hole, and there is no possibility that the contact resistance and the sliding resistance increase and the durability is not impaired. As a result, it is possible to provide a spring contact probe having stable contact resistance characteristics and the like.
[0017]
In the spring contact probe according to claim 2, since the closing member has a cup shape, the closing member can be configured to be lightweight, and by inserting one end of the spring into the cup, the position of one end of the spring can be determined. Is stable.
[0018]
In the spring contact probe according to the third aspect, since the closing member has a cylindrical shape, the structure is simple and the parts can be easily manufactured. In particular, the smaller the inner diameter of the conductive tube, the more prominent the manufacturing.
[Brief description of the drawings]
1A is a longitudinal sectional view of a first embodiment of a spring contact probe of the present invention, and FIG. 1B is an external perspective view of a cup-shaped closing member.
FIG. 2 (a) is a longitudinal sectional partial view of a second embodiment of the spring contact probe of the present invention, and FIG. 2 (b) is an external perspective view of a cylindrical blocking member.
FIG. 3 is a longitudinal sectional view of an example of a conventional spring contact probe.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Conductive tube 12 Spring 14 Plunger 14a Large diameter part 14b Contact part 16, 18 Through-hole 20, 22 Closure member

Claims (3)

A plunger is slidable in the axial direction in a conductive tube provided with a through hole on the closed end side and plated with a conductive thin film on the inner peripheral wall, and arranged so that it does not come out by protruding the contact part, A spring contact probe in which a spring is contracted in the conductive tube so as to elastically urge the plunger in a protruding direction, and the plunger is slidably contacted with an inner peripheral wall of the conductive tube to make electrical conduction. Between the closed end in the tube and the spring, a closing member that fits and contacts the inner peripheral wall of the conductive tube is disposed, and the closing member is elastically biased toward the closed end by the spring, A spring contact probe configured to block communication between the through hole and the side of the conductive tube on which the plunger is disposed by a closing member . 2. The spring contact probe according to claim 1, wherein the closing member is configured in a cup shape that fits and contacts the inner peripheral wall of the conductive tube and into which one end of the spring is inserted . 2. The spring contact probe according to claim 1, wherein the blocking member is formed in a cylindrical shape that fits and contacts the inner peripheral wall of the conductive tube.