JPH0562732A - Contact pin - Google Patents

Abstract

PURPOSE:To provide contact pins in which a given contact pressure can be obtained with the contact region of a contact spring always fixed, and the production of resin powder is eliminated even insertion and extraction are repeated when the contact pins are inserted in a through hole. CONSTITUTION:This contact pin is composed of a resin-made pin main body consisting of a conical tip part, a small-diameter shaft, and a large-diameter grip part; and a contact spring B composed of actually cylindrical spring material having a length slightly shorter than that of the shaft, provided coaxially to the shaft in its periphery, and forming an axis direction cut part 4 on a side. The cross section shape of the contact spring B is an elliptical shape having a pair of symmetric projections 11 and 12 on a long diameter orthogonal to a short diameter passing the cut part 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a main switchboard (M
XY) of a matrix board composed of an X-direction wiring pattern layer and a Y-direction wiring pattern layer used for DF)
The present invention relates to a contact pin that is inserted into a through hole that penetrates an intersection and short-circuits between XY patterns, and more specifically to a novel structure of a cylindrical contact spring that constitutes an outer peripheral surface of the contact pin.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional contact pin for a matrix board comprises a conical tip portion 1, a shaft 2 following the tip portion 1, and a stepped cylindrical grip portion 3. It has a resin main body A. A cylindrical contact spring B made of a spring material having a slit 4 on a side surface along a generatrix is loosely fitted between the tip portion 1 and the grip portion 3 of the main body. The length of the contact spring B is set to be slightly shorter than the length of the shaft 2, and the contact spring B can move freely along the shaft 2 within the range of the difference.

The contact spring B is provided with a plurality of tongue pieces 5 and 6 projecting in a zigzag shape at both ends thereof so that the tongue pieces 5 and 6 can be easily inserted into and removed from the through hole 8 of the matrix board 7. It is bent so as to incline inward.
Further, in the free state in which no external force is applied, the diameter of the contact spring B is set to be slightly larger than the inner diameter of the through hole 8.

When the contact pin having such a structure is inserted into the through hole 8, the contact spring B enters the through hole with its diameter contracted, and the elastic force accumulated by the deformation of the contact spring B causes the inside of the through hole 8 to shrink. The patterns 9 and 10 exposed on the peripheral surface are contacted with a predetermined contact pressure.

[0005]

In the above-mentioned conventional contact pin, since the contact spring has a circular sectional shape, either the pattern exposed on the inner peripheral surface of the through hole or the entire circumference thereof is formed. Will be contacted in the area of. For this reason, the contact points of the two become unclear, and it is difficult to confirm whether or not the desired contact pressure has been obtained in the planned contact area, or contact at a point different from the contact point planned for the spring design. There were some drawbacks.

In addition to this, in the conventional contact pin, when the insertion / removal is repeated with respect to the through hole, the resin forming the grip portion of the pin interferes with the tapered tongue piece of the contact spring. The phenomenon of wear and powder formation is observed. The mechanism of powder generation will be described with reference to the schematic diagram shown in FIG. At the initial stage of the operation of inserting the pin into the through hole 8, first, as shown in FIG.
Contracts, and then the trailing region II contracts. When the pin is inserted, the contact spring B moves rearward along the shaft 2, and the tip of the rear tongue piece 6 is in contact with the end surface of the grip portion 13 of the main body A. Therefore, in the state of (b), when the diameter of the contact spring B contracts, the tongue piece 6 of the contact spring B
The tip end of the gripper slides on the end surface of the grip portion 3 while being pressed against the end surface, and the grip portion 3 is scraped off and powdered.

The resin powder thus produced is not preferable because it causes poor contact. The present invention solves the above-mentioned problems of the prior art, and when the contact pin is inserted into the through hole, the contact area of the contact spring is always fixed and a predetermined contact pressure is obtained, and even if the insertion / removal is repeated, the resin An object is to provide a contact pin that does not generate powder.

[0008]

The object of the present invention is to provide a resin pin body having a conical tip, a small-diameter shaft, and a large-diameter grip, and a length slightly shorter than the shaft. A contact spring made of a substantially cylindrical spring material having a slit in the axial direction on the side surface and provided coaxially with the shaft, the sectional shape of the contact spring being the slit. It is achieved by a contact pin characterized by having an elliptical shape having a pair of protrusions symmetrically on a major axis orthogonal to the minor axis passing through.

The front and rear edges of the contact spring are composed of a plurality of tongues formed in a zigzag shape, and these tongues have a tapered taper for facilitating the insertion into and removal from the through hole, and further the trailing edge is formed. It is desirable that the tip of the tongue is substantially parallel to the end face of the gripping part facing the tongue, and the tongue is processed so that the contact area increases.

[0010]

In the contact pin of the present invention, when a diametrical external force is applied to the contact spring from the surroundings when the contact pin is inserted into the through hole, the contact spring contracts its diameter by the action of the slit, and the contact pin is urged in the outward direction. It is inserted into the through hole with the elastic force stored. At that time, the contact spring comes into contact with the inner peripheral wall of the through hole at the positions of the protrusions at both ends of the maximum diameter. Therefore, the contact position is always constant, a contact pressure of a predetermined magnitude is obtained, and a stable connection with the through hole is guaranteed.

According to a preferred embodiment, the rear end of the contact spring is processed so as to come into contact with the end surface of the grip portion of the pin body facing the contact spring over a wide area, so that the contact spring is inserted when the pin is inserted. The action of the sharp edge of shaving off the end face of the gripping part is eliminated, and the generation of resin powder from the pin body is prevented. Hereinafter, the present invention will be described in more detail with reference to the preferred embodiments shown in the drawings.

[0012]

The first embodiment of the contact pin of the present invention relates to the improvement of the cross-sectional shape of the conventional contact spring. That is, in the conventional contact spring, the shape of the central region in contact with the pattern in the through hole is a cylindrical shape having a substantially perfect circular cross section with no protrusion on the surface as shown in FIG. 4 (b). However, in the present invention, as shown in FIG. 1, it has an elliptical cross section, and is provided with a pair of projections 11 and 12 extending in the axial direction in both end regions of the major axis orthogonal to the minor axis passing through the slit 4. .

Therefore, when it is inserted into the through hole 8, it is inevitably brought into contact with the inner peripheral wall of the through hole in the region of the protrusions 11 and 12, and a reliable electrical connection is obtained. or,
Since the contact area can be limited in this way, even when an expensive treatment such as gold plating is performed to stabilize the electrical connection, the area can be reduced, which contributes to a reduction in manufacturing cost.

FIG. 2 is a side sectional view taken along the axis of the contact spring of the second embodiment, which is a modification of the embodiment of FIG. According to this, the tongue piece 6 at the trailing edge of the contact spring B, which is conventionally bent inward with a loose taper as shown in FIG. 1, is bent substantially at a right angle, and the surface parallel to the end surface of the grip portion 3 is formed. Is configured to be formed. As a result, the end surface of the grip portion 3 comes into contact with the tongue piece of the contact spring with a large contact area, and the scraping phenomenon of this portion at the time of insertion into the through hole, which has been mentioned as a drawback of the above-mentioned conventional technique, is eliminated.

In order to achieve this purpose, FIG.
In addition to the above example, as shown in FIG. 3, the tip portion of the tongue piece 6 at the trailing edge may be shaved to increase the contact area with the grip portion 3.

[0016]

According to the present invention, since the contact spring has an elliptical cross-sectional shape and the protrusions are provided at both end regions of its major axis, the contact region with the inner peripheral wall of the through hole is necessarily the protrusion. Limited and reliable electrical connections are guaranteed. Further, since the tongue piece on the trailing edge of the contact spring is machined to increase the contact area with the grip, the end surface of the grip is scraped off by the contact spring during insertion into the through hole, which causes powder. Disappears.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a cross-sectional shape of a contact spring according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a sectional shape in the axial direction of a contact spring according to the second embodiment.

FIG. 3 is a sectional view showing an axial sectional shape of a contact spring of another embodiment that achieves the same purpose as the example of FIG.

FIG. 4A is a side view showing the structure and operation of a conventional contact pin, and FIG. 4B is a sectional view taken along line XX of FIG. 4A showing a cross-sectional shape of a conventional contact spring. .

5 (a) and 5 (b) are side sectional views showing a process of powder generation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tip part 2 ... Shaft 3 ... Gripping part 4 ... Notch 5,6 ... Tongue 7 ... Matrix board 8 ... Through hole 9,10 ... Pattern 11, 12 ... Protrusion A ... Pin body B ... Contact spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyonori Nakamura 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (72) Inventor, Tsukasa Seino 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Co., Ltd. (72) Inventor Yotaro Yoh, 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Japan Telegraph Telephone Co., Ltd. (72) Inventor Shigeru Umemura 1-1-6 Uchiyukicho, Chiyoda-ku, Tokyo Nihon Telegraph Telephone Co., Ltd. (72) Inventor Koichi Ito 1-7-12 Toranomon, Minato-ku, Tokyo Oki Electric Industry Co., Ltd. (72) Inventor Takao Abe 3864 Izumi-cho, Izumi-ku, Yokohama-shi, Kanagawa Tokyo Haichi Co., Ltd. Within

Claims (2)

[Claims] 1. A resin pin body (A) comprising a conical tip portion (1), a small-diameter shaft (2) and a large-diameter gripping portion (3), and a bit smaller than the shaft (2). A contact spring (B) made of a substantially cylindrical spring material having a short length and provided coaxially with the shaft around the shaft and having axial slits (4) on the side surface. The cross-sectional shape of the contact spring (B) is a pair of protrusions (11, 1) symmetrically on the major axis orthogonal to the minor axis passing through the slit (4).
2. A contact pin having an oval shape having 2). 2. The front and rear edges of the contact spring (B) are composed of a plurality of tongues (5, 6) formed in a zigzag shape, and these tongues (5, 6) can be easily inserted into and removed from a through hole. Tongue (6) which has a taper tapering as shown in FIG.
The contact pin according to claim 1, wherein the tip of the contact pin is substantially parallel to the end face of the gripping part (3) facing the end face, and the contact area is increased.