JPH10319038A - Contact pin - Google Patents

Abstract

(57) [Problem] To provide a contact pin that can securely contact only a contact portion without increasing cost and even when the area of the contact portion is small. A contact pin includes a pin body, a hole formed in a tip portion of the pin body, a conductive rubber attached to the hole, and the like. The tip 402 of the pin body 4 is formed in a cylindrical shape with a diameter larger than that of the base and the middle, and the tip end surface of the tip 402 is formed in a spherical shape. The hole 6 extends along the center axis of the pin main body 4 inside the tip part 402 and is formed in an open shape on the tip end surface of the tip part 402. The cross section of the hole 6 is circular, and the cross section of the hole 6 is uniform in the extending direction of the hole 6. The conductive rubber 8 is formed in a columnar shape with a uniform circular section having a smaller diameter than the tip 402. The conductive rubber 8 is inserted into the hole 6 and fixed in the hole 6 while being compressed by the wall of the hole 6, and the leading end of the conductive rubber 8 protrudes from the leading end surface of the leading end 402 of the pin body 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact pin used for electrical inspection of an object to be inspected or charging and discharging of a battery.

[0002]

2. Description of the Related Art Contact pins are widely used for inspecting a pattern formed on a printed circuit board or for charging and discharging a battery. Inspection of a pattern on a printed board using contact pins is a perspective view in FIG.
As shown in the front view of FIG. 2B, after the printed circuit board 52 is positioned and placed inside the jig main body 50, the cover plate 54 is closed. As a result, the plurality of contact pins 56 attached to the cover plate 54 come into contact with the terminals on the printed circuit board 52 and are connected to the measuring instrument via the lead wires 58, so that the operation state of the circuit of the printed circuit board 52 and the like are obtained. Is inspected. As shown in the perspective view of FIG. 7, the battery is charged and discharged by applying lid plates 64 and 66 from above and below a battery storage 62 in which a large number of batteries 60 are stored, and respectively applying the upper and lower lid plates 64 and 66. This is performed by bringing the attached contact pins 68 into contact with the terminals of the battery 60 and connecting each battery 60 to a charging / discharging device via a lead wire 70.

[0003] In this kind of contact pin, generally, a contact portion to an object to be inspected is made of metal, so that the following problem occurs. If the tip of the contact pin is sharpened to ensure low-resistance contact, a dent is formed at the contact portion of the product.
If the tip of the contact pin is rounded so as not to damage it, the contact area with the product is small, so that a contact failure is likely to occur due to dust or dust. Even if the tip of the contact pin is formed in a plane, the contact is eventually point contact, which is the same result as when the tip is rounded. Since the contact resistance increases due to the adhesion of the insulator to the tip of the contact pin, it is necessary to periodically polish the tip of the contact pin with a brush or the like. In order to solve such a problem, a contact pin provided with a conductive rubber at the tip is provided, for example, in Japanese Utility Model Laid-Open No. 61-112276 and Japanese Utility Model Laid-Open No. 2-1767.
No. 1 and the like.

[0004]

However, although these prior arts can solve the above-mentioned problems, in order to prevent the conductive rubber from falling off, the conductive rubber is shaped to cover the tip of the pin main body. It is necessary to form an engaging portion of a complicated shape on both the main body and the conductive rubber,
There was a problem that increased the cost. In addition, in the case where the conductive rubber is placed on the tip of the pin body, if the area of the contact part where the contact pin contacts is small, it will come into contact with the area that should not be contacted. There was a problem that could not be performed properly. The present invention has been devised in view of the above circumstances, and it is an object of the present invention to ensure that only the contact portion is brought into contact without increasing the cost and even when the area of the contact portion is small. It is to provide a contact pin which can be used.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a contact pin used for electrical inspection of an object to be inspected, charging / discharging of a battery, and the like, wherein the pin body is formed of a conductive material. A hole extending in a uniform cross section along the center axis of the pin body inside the tip of the pin body and formed in an open shape at the tip of the pin body; and a uniform cross section smaller than the tip of the pin body. And a conductive rubber that is inserted and fixed in the hole while being compressed by the wall of the hole, and has a tip that projects from the tip of the tip of the pin body. .

According to the present invention, when the conductive rubber is mounted on the pin body, it is sufficient to simply make a hole in the pin body and prepare an elongated conductive rubber having a columnar or quadrangular prism shape. The conductive rubber can be mounted on the pin body without complicating the shape of the pin body for attaching the rubber and the shape of the conductive rubber. In addition, since the conductive rubber has a cross section smaller than the tip of the pin body, even when the area of the contact portion for contacting the contact pin is small, it can be reliably brought into contact only with the contact portion.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings. 1A is a front view of a contact pin according to the first embodiment, FIG. 1B is a perspective view of a tip of the contact pin, and FIG. 1C is a front view of a tip of the contact pin. Is shown. The contact pins 2 are used for electrical inspection of the printed circuit board 52 and charging / discharging of the battery 60 as described above, and are generally provided on the cover plates 54, 64, 66 and the like shown in FIGS. The contact pins 2 are movably movable in the direction and are urged in a protruding direction by a coil spring or the like. The contact pin 2 includes a pin body 4, a hole 6 formed in a tip 402 of the pin body 4, a conductive rubber 8 attached to the hole 6, and the like.

A lead wire 12 is connected to the base of the pin body 4 via the terminal 10, and the tip 402 of the pin body 4 is formed in a columnar shape with a diameter larger than that of the base or the middle. The tip end face of the tip 402 is formed as a convex spherical surface so that the pin body 4 does not contact the contact portion, and only the conductive rubber 8 contacts. The hole 6 is formed in the tip 402. The hole 6 extends along the center axis of the pin main body 4 inside the front end portion 402 and is formed in an open shape on the front end surface of the front end portion 402. The cross section of the hole 6 is circular, and the cross section of the hole 6 is uniform in the extending direction of the hole 6.
The conductive rubber 8 is formed in a cylindrical shape with a circular uniform cross section having a smaller diameter than the tip portion 402. The conductive rubber 8 is inserted into the hole 6 while being compressed by the wall of the hole 6 and fixed in the hole 6, and the tip of the conductive rubber 8 projects from the tip end surface of the tip 402 of the pin body 4. It is arranged to be. Therefore, in this embodiment, the diameter of the conductive rubber 8 is formed to be slightly larger than the diameter of the hole 6.

According to such a contact pin 2, when the conductive rubber 8 is mounted on the pin body 4, the pin body 4
It is sufficient to make a hole 6 in the hole and prepare a columnar conductive rubber 8. Therefore, the conductive rubber 8 can be formed without complicating the shape of the pin body 4 for mounting the conductive rubber 8 and the shape of the conductive rubber 8. The rubber 8 can be attached to the pin body 4, which is advantageous in reducing costs. The conductive rubber 8 is formed in a cylindrical shape having a diameter smaller than that of the tip 402, and when the conductive rubber 8 comes into contact with the contact portion, the contact area is reduced by the cross-sectional area of the conductive rubber 8. It is only necessary to add the area of increase due to the strain of the contact pin 2 and it is small. Therefore, even when the area of the contact portion for contacting the contact pin 2 is small, it can be reliably brought into contact only with the contact portion. Etc. can be performed appropriately.

Next, a second embodiment will be described. FIG. 2A is a perspective view of the tip of a contact pin according to the second embodiment, and FIG. 2B is a diagram showing the relationship between holes and conductive rubber. In the second embodiment, the conductive rubber 8 is formed not in a columnar shape but in a square columnar shape with a uniform square cross section. In the second embodiment, four corners 802 of the conductive rubber 8 are inserted into the hole 6 while being compressed, and are fixed in the hole 6 on the inner wall of the hole 6. Therefore, in this embodiment, the diameter of a virtual circle connecting the vertices of the four corners 802 of the conductive rubber 8 is formed to be slightly larger than the diameter of the hole 6. Thus, by forming the hole 6 of the contact pin 2 in a circular shape and forming the conductive rubber 8 in a square pillar shape, the hole 6 of the contact pin 2 is formed in a circular shape and the conductive rubber 8 is formed in a cylindrical shape. Conductive rubber 8 without increasing dimensional accuracy
Can be easily and reliably attached to the contact pin 2.

Next, a third embodiment will be described. FIG. 3A is a perspective view of a tip of a contact pin according to a third embodiment, and FIG. 2B is a view showing a relationship between holes and conductive rubber. In the third embodiment, the conductive rubber 8 is formed not in a columnar shape but in a triangular prism shape with a triangular uniform cross section. In the second embodiment, three corners 804 of the conductive rubber 8 are inserted into the hole 6 while being compressed, and are fixed in the hole 6 on the inner wall of the hole 6. Therefore, in this embodiment, the diameter of an imaginary circle connecting the vertices of the three corners 804 of the conductive rubber 8 is formed to be slightly larger than the diameter of the hole 6. According to the third embodiment, as in the second embodiment, the conductive rubber 8 can be easily and reliably attached to the contact pin 2 without increasing the dimensional accuracy.

Next, a fourth embodiment will be described. FIG. 4 is a cross-sectional view of a tip of a contact pin according to a fourth embodiment. In the fourth embodiment, the conductive rubber 8
Are made different in shape of the hole 6 while maintaining a cylindrical shape. In the fourth embodiment, the hole 6 is formed by shifting the centers of the three circular holes 24 so that they are overlapped at the center of the tip 402. The inner wall of the hole 6 has a hole 6 due to the overlapping portion of the circular hole 24.
Are formed inside the hole, and the conductive rubber 8 is inserted into the hole 6 while being compressed by the three convex wall portions 602 and is fixed in the hole 6. Therefore, in this embodiment, the conductive rubber 8 has a diameter slightly larger than the diameter of an imaginary circle connecting the vertices of the three convex wall portions 602.
Are formed. According to the fourth embodiment, as in the second and third embodiments, the conductive rubber 8 can be easily and reliably attached to the contact pins 2 without increasing the dimensional accuracy.

Next, a fifth embodiment will be described. FIG. 5A is a front view of a tip of a contact pin according to a fifth embodiment, and FIG. 5B is a perspective view of a conductive rubber. In the fifth embodiment, the shape of the conductive rubber 8 is different. In the fifth embodiment, a portion in which the conductive rubber 8 protrudes from the tip of the pin body 4 is provided with an umbrella-shaped tip 812 having a cross section larger than the portion to be inserted into the hole 6. It is. Such a tip 812
Although the contact area increases, the electric resistance value can be reduced by providing.

[0014]

As is clear from the above description, the present invention
A contact pin used for electrical inspection of an object to be inspected, charging / discharging of a battery, and the like, wherein a pin main body formed of a conductive material and a center axis of the pin main body inside a tip portion of the pin main body. A hole extending in a uniform cross-section and formed in an open shape at the tip of the pin body, and formed in an elongated shape with a uniform cross-section smaller than the tip of the pin body, and compressed into the hole while being compressed by the wall of the hole. The pin is inserted and fixed, and has a tip provided with a conductive rubber projecting from the tip of the tip of the pin body. Therefore, without cost, and
Even when the area of the contact portion is small, it is possible to reliably contact only the contact portion.

[Brief description of the drawings]

1A is a front view of a contact pin according to a first embodiment, FIG. 1B is a perspective view of a tip of the contact pin, and FIG. 1C is a front view of a tip of the contact pin. .

FIG. 2A is a perspective view of a tip of a contact pin according to a second embodiment, and FIG. 2B is a diagram showing the relationship between holes and conductive rubber.

FIG. 3A is a perspective view of a tip of a contact pin according to a third embodiment, and FIG. 3B is a diagram showing a relationship between holes and conductive rubber.

FIG. 4 is a sectional view of a tip of a contact pin according to a fourth embodiment.

FIG. 5A is a front view of a tip of a contact pin according to a fifth embodiment, and FIG. 5B is a perspective view of a conductive rubber.

FIGS. 6A and 6B are explanatory diagrams for inspecting a pattern of a printed circuit board using contact pins, respectively.

FIG. 7 is an explanatory diagram of charging and discharging a battery using contact pins.

[Explanation of symbols]

2 contact pin, 4 pin body, 6 hole, 8 conductive rubber, 402 tip.

Claims (6)

[Claims] 1. A contact pin used for electrical inspection of an object to be inspected, charging / discharging of a battery, and the like, comprising: a pin body formed of a conductive material; and a pin body inside a tip portion of the pin body. A hole extending in a uniform cross-section along the central axis and formed in an open shape at the tip of the pin body, and formed in an elongated shape with a uniform cross-section smaller than the tip of the pin body, and compressed by the wall of the hole A conductive rubber that is inserted and fixed into the hole while being fixed, and has a leading end protruding from the tip of the leading end of the pin body. 2. The contact pin according to claim 1, wherein each of the hole and the conductive rubber has a circular cross section. 3. The contact pin according to claim 1, wherein the hole has a circular cross section, and the conductive rubber has a polygonal cross section. 4. The hole is formed by shifting a center of a plurality of circular holes such that a plurality of circular holes overlap in a center portion of the pin body, and an inner wall of the hole has the circular hole. The contact pin according to claim 1, wherein a convex wall portion is formed inside the hole by the overlapping portion, the conductive rubber has a circular cross section, and the conductive rubber is compressed by the convex wall portion. 5. The contact pin according to claim 1, wherein the tip of the tip of the pin main body is formed as a convex spherical surface. 6. The contact pin according to claim 1, wherein a portion of the conductive rubber projecting from a tip end of the pin body has a larger cross section than a portion inserted into the hole.