JP2004273256A - Press-fit terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press-fit terminal in which it is possible to reduce a redundant rotating force formed when press-fitted to a throughhole of a printed circuit board even in the case the cross-sectional shape of a press-fit connecting part is nearly an N-type. <P>SOLUTION: In the press-fit terminal 10 having the press-fit connecting part 20 to come into electrically contact with a throughhole 14 of the printed circuit board 13, the press-fit connecting part 20 is constituted of elastic contact parts 21 elastically contacted with a peripheral face of the throughhole 14 and facing each other when seen on a perpendicular cross-sectional face in the longitudinal direction, and a coupling part 22 which is installed diagonally between these elastic contact parts 21, and in which its both end parts are coupled with the elastic contact parts 21, and furthermore, this coupling part 22 is formed to be longer than the shortest counter distance between the elastic contact parts 21, and shorter than the longest counter distance. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a press-fit terminal, and more particularly, to a press-fit terminal having a press-fit connection that makes electrical contact with a through hole of a printed circuit board.
[0002]
[Prior art]
In general, the method of fixing the printed circuit board and the terminal is to insert the terminal into the through hole of the printed circuit board and fix it by soldering, or to press-fit the terminal into the through hole and mechanically fix it without soldering. There is known a method of fixing the above.
[0003]
The former fixing method provides sufficient electrical connection and fixing strength, but requires soldering, and thus has many problems such as a complicated connection process between the printed circuit board and the terminals. Therefore, in recent years, the latter fixing method that does not use solder has been widely used.
[0004]
The terminal used in this latter fixing method is called a press-fit terminal, and is generally formed by processing a metal wire having excellent conductivity and inserted into a through hole of a printed circuit board. And a mounting portion to be mounted on the board connector or the like, and a press-fit connection portion disposed between the insertion portion and the mounting portion and in electrical contact with the through hole.
[0005]
As a cross-sectional shape of a press-fit connection part in this type of press-fit terminal, for example, the one shown in FIG. 8 is known.
[0006]
FIG. 8 shows a cross-sectional shape of a press-fit connection portion 50 in a so-called solid-type press-fit terminal. The cross-sectional shape is rectangular, and points A, B, C, D It is configured to be in electrical contact with and fixed to the peripheral surface 52 of the through hole 51 at four points (for example, see Patent Document 1).
[0007]
However, in such a solid type, since the amount of elastic deformation of the press-fit connection is small, unless the through-hole diameter is maintained to a very strict tolerance, mechanical holding force and electrical contact can be maintained stably. There is a problem that can not be.
[0008]
Therefore, recently, by deforming the cross-sectional shape of the press-fit connection portion into N-type, M-type, H-type, etc., the amount of elastic deformation of the press-fit connection portion is increased, and the size of the through-hole diameter of the printed circuit board is increased. A so-called compliant type press-fit terminal, which is easy to cope with fluctuations, has become mainstream.
[0009]
FIGS. 9A and 9B show a cross-sectional shape of a conventional press-fit connecting portion having an N-shaped cross-sectional shape. The cross-sectional shape of the press-fit connecting portion 53 is substantially the same as the thickness y of the inter-groove connecting portion 55 between the pair of grooves 54 than the thickness x of the arm-like portion 57 forming the pair of corners 56. The corner portion 56 is in electrical contact with the peripheral surface 59 of the through hole 58, and the arm portion 57 is deformed and comes into close contact with the through hole 58 (see FIG. 9A). (See FIG. 9B) (for example, see Patent Document 2).
[0010]
FIGS. 10A and 10B show cross-sectional shapes of another conventional press-fit connecting portion having an N-shaped cross-sectional shape. The cross-sectional shape of the press-fit connecting portion 60 has a substantially N-shaped shape including a pair of convexly curved outer surfaces 61, a pair of grooves 62, and a flexible portion 63 connecting the grooves 62. (See FIG. 10 (a)), and a pair of outer surfaces 61 makes good electrical contact with the peripheral surface 65 of the through hole 64 due to the bending of the flexible portion 63 (FIG. 10 (b)). )) (For example, see Patent Document 3).
[0011]
In addition, for example, Patent Documents 4 and 5 disclose techniques (not shown) relating to a press-fit connection portion having an M-shaped cross-sectional shape and an H-shaped cross-sectional shape.
[0012]
[Patent Document 1]
Japanese Patent Publication No. 62-17356 [Patent Document 2]
Japanese Patent Publication No. 3-57587 [Patent Document 3]
JP-A-58-189970 [Patent Document 4]
Japanese Patent No. 2929176 [Patent Document 5]
JP-A-5-21073
[Problems to be solved by the invention]
Such a compliant press-fit terminal having a cross-sectional shape such as N-type, M-type, or H-type can be used when a high contact load is required. In such a case, it can be said that the sectional shape is effective.
[0014]
However, the M type has a problem that it is difficult to manufacture because of its complicated shape, and the H type has a problem that it is difficult to press-fit into the through hole (large insertion resistance).
[0015]
On the other hand, the N type has a relatively simple shape and is easy to manufacture as compared with the M type and the like, and the press fitting process into the through hole in the printed circuit board in comparison with the H type etc. On the other hand, there is an advantage that an unnecessary load is not applied to the printed circuit board because a peak is hardly generated in the insertion load.
[0016]
However, in spite of the above-mentioned advantages, the N-type has a cross-sectional shape that is not line-symmetric but point-symmetric. There is a problem that extra rotation is required at the time of compression deformation.
[0017]
That is, such rotation applies a load to the printed circuit board in the same direction, and thus may cause a problem that the mounted components on the printed circuit board and the soldered portion thereof are damaged.
[0018]
Therefore, the problem to be solved by the present invention is to reduce an unnecessary rotational force generated when press-fitting a printed circuit board into a through-hole, even when the cross-sectional shape of the press-fit connection portion is substantially N-shaped. It is to provide a possible press-fit terminal.
[0019]
[Means for Solving the Problems]
In order to solve this problem, a press-fit terminal according to claim 1 of the present invention is a press-fit terminal having a press-fit connection portion inserted into a through-hole of a printed circuit board and making electrical contact with the through-hole. The press-fit connection portion, when viewed in a cross section perpendicular to the longitudinal direction, is elastically contacted with the peripheral surface of the through-hole and opposed to each other, and is obliquely provided between the pair of elastic contact portions. And a connecting portion whose both ends are connected to each elastic contact portion, the connecting portion being longer than the shortest opposing distance between the pair of elastic contact portions, and shorter than the longest opposing distance. The gist is that it is formed.
[0020]
The press-fit terminal according to claim 2 is the press-fit terminal according to claim 1, wherein a portion of each of the elastic contact portions that contacts the through hole has a curvature substantially equal to a curvature of a peripheral surface of the through hole. The gist is that it is formed in.
[0021]
The press-fit terminal according to claim 3 is the press-fit terminal according to claim 1 or 2, wherein the width of the connecting portion is formed to be thinner than the width of each of the elastic contact portions. And
[0022]
A press-fit terminal according to a fourth aspect is the press-fit terminal according to the first to third aspects, wherein a chamfered portion is formed at a connection portion between each of the elastic contact portions and the connection portion. That is the gist.
[0023]
The press-fit terminal according to claim 5 is the press-fit terminal according to claims 1 to 4, wherein the press-fit connection portion is located at a center of the connection portion when viewed in a cross section perpendicular to the longitudinal direction. The point is that they are formed in a substantially point-symmetrical shape.
[0024]
According to the press-fit terminal according to the present invention, the press-fit connection portion, when viewed in a cross-section perpendicular to the longitudinal direction, is elastically contacted with the peripheral surface of the through hole and opposes each other. A connecting portion that is obliquely provided between the pair of elastic contact portions and whose both ends are connected to each elastic contact portion, the connecting portion being longer than the shortest facing distance between the pair of elastic contact portions. Further, since the press-fit connection portion is formed shorter than the longest facing distance, when the press-fit connection portion is press-fitted into the through hole of the printed circuit board, the amount of compressive deformation of the press-fit connection portion in the rotation direction is reduced. Therefore, no extra rotation is applied when the printed circuit board is pressed into the through hole, and a force in the rotational direction is less likely to be applied to the printed circuit board.
[0025]
Therefore, the press-fit terminal is less likely to cause problems such as damage to the components mounted on the printed circuit board and the soldered portions thereof.
[0026]
In addition, when the portion of each elastic contact portion that comes into contact with the through hole is formed to have a curvature substantially equal to the curvature of the peripheral surface of the through hole, the contact area between the press-fit terminal and the through hole increases, and the connection is made. Reliability is further improved.
[0027]
Further, when the width of the connecting portion is formed thinner than the width of each elastic contact portion, the connecting portion is easily elastically deformed, and the elastic force generated by this connecting portion becomes large, so that the peripheral surface of the through hole is formed. Each of the elastic contact portions is strongly pressed against the elastic member so that a sufficient retaining load can be obtained and a larger contact load can be obtained.
[0028]
Further, when a chamfered portion is formed at a connecting portion between each elastic contact portion and the connecting portion, stress concentration occurring at that portion can be reduced, and destruction or the like due to the stress concentration hardly occurs. Also excellent in durability.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
[0030]
As shown in FIG. 1, the press-fit terminal 10 according to the embodiment of the present invention is formed into a long and narrow rectangular bar shape by pressing a metal wire having excellent conductivity such as a copper alloy or phosphor bronze. I have. The press-fit terminal 10 is bent into, for example, an L-shape, and a mounting portion 11 at one end thereof is attached to a board connector housing (not shown) by press-fitting or the like, and a board connecting portion 12 at the other end is formed on the printed circuit board 13. It is designed to be inserted into the through hole 14.
[0031]
On the other hand, as shown in FIG. 2, the printed circuit board 13 has various conductive paths 15 formed on the surface thereof, and has a large number of through holes 14 formed therein. A contact portion 16 is formed on the inner peripheral surface of the through hole 14 by plating or the like, and is connected to the conductive path 15.
[0032]
As shown in FIG. 2, the board connecting portion 12 of the press-fit terminal 10 has a guide portion 17 formed at a tip thereof for guiding a terminal inserted into the through hole 14, and a through hole 14 above the guide portion 17. A pair of elastically deformable portions 18 are formed over a region approximately twice the depth of the elastic member. Each of the elastic deformation portions 18 has a thick band shape, and is formed to bulge outward in a substantially arc shape with a pair of groove portions 19 interposed therebetween.
[0033]
However, at a position slightly upward from the central portion in the longitudinal direction, the outer surface is a straight portion 18A over substantially one third of the entire length, and is parallel to each other. A portion corresponding to the linear portion 18A is a press-fit connection portion 20 and is in electrical contact with the contact portion 16 of the through hole 14.
[0034]
FIG. 3 shows an A-A cross section of the press-fit connection portion 20. As shown in FIG. 3, the press-fit connecting section 20 has a pair of elastic contact sections 21 and a connecting section 22.
[0035]
Each elastic contact portion 21 is formed such that its outer portion 23 has a curvature substantially equal to the curvature of the peripheral surface of the through hole 14, and can be satisfactorily elastically contacted with the contact portion 16 of the through hole 14.
[0036]
The connecting portion 22 is obliquely provided between the inner portions 24 of the respective elastic contact portions 21, and both ends thereof are connected to the inner portions 24 of the respective elastic contact portions 21. Further, the thickness y of the connecting portion 22 is formed to be thinner than the thickness x of the elastic contact portion 21, and chamfered portions C1 and C2 are formed at the connecting portion between the connecting portion 22 and each elastic contact portion 21. , Smoothly combined.
[0037]
Here, the length of the connecting portion 22 is set to be longer than the shortest opposing distance between the inner portions 24 of the respective elastic contact portions 21 and shorter than the longest opposing distance. That is, as shown in FIG. 4, if the length of the connecting portion 22a is the same as the shortest opposing distance between the inner portions 24 of the respective elastic contact portions 21, the connecting portion 22a becomes H-shaped, and As shown in FIG. 5, when the length of the connecting portion 22b is the same as the longest facing distance between the inner portions 24 of the respective elastic contact portions 21, the connection portion 22b is completely N-shaped. However, in the present invention, since the connecting portion 22 is set to be longer than the shortest opposing distance between the inner portions 24 of the respective elastic contact portions 21 and shorter than the longest opposing distance, it is inevitable. In addition, the sectional shape shown in FIG. 3 is not obtained, and the sectional shape shown in FIGS. 4 and 5 is not H-shaped or completely N-shaped.
[0038]
The outer diameter D of the press-fit connecting portion 20 is formed to be 10 to 20% larger than the diameter S of the inner periphery of the through hole 14.
[0039]
Next, the operation of the press-fit terminal according to the embodiment of the present invention will be described.
The board connecting portion 12 of the press-fit terminal 10 is inserted from above into the corresponding through hole 14 of the printed circuit board 13 as shown by an arrow Y in FIG. In the middle of the insertion, the lower inclined portion 18B on the outer surface of the elastic deformation portion 18 hits the upper edge of the through-hole 14, and when the press-fit terminal 10 is further inserted, the inclined portion 18B is used as a guide and FIG. As shown in FIG. 7 and FIG. When the press-fit connection portion 20 is pushed to a predetermined position reaching the center depth position of the through hole 14, the insertion operation is stopped.
[0040]
At this time, the connecting portion 22 is compressed and deformed while changing the inclination angle. However, the length of the connecting portion 22 is longer than the shortest opposing distance between the inner portions 24 of the elastic contact portion 21 and the longest opposing distance. Since it is set to be shorter than this, it is press-fitted into the through hole with a small amount of compressive deformation in the rotation direction.
[0041]
In addition, the outer portion 23 of each elastic contact portion 21 is pressed against the contact portion 16 of the through hole by the elastic force of the connecting portion 22 in the extension direction and the elastic force of the elastic contact portion 21 in the opening direction. As a result, the press-fit terminal 10 is held in the through hole 14 in a retaining state, and is electrically connected to the contact portion 16.
[0042]
According to the press-fit terminal according to the embodiment of the present invention, no extra rotation is applied at the time of press-fitting the printed circuit board into the through-hole, and a force in the rotating direction is hardly applied to the printed circuit board. For this reason, the press-fit terminal is less likely to cause problems such as damage to components mounted on the printed circuit board and soldered portions thereof.
[0043]
In addition, since each elastic contact portion has an outer portion formed with a curvature substantially equal to the curvature of the peripheral surface of the through hole, a contact area between the press-fit terminal and the through hole is increased, and connection reliability is further improved. .
[0044]
In addition, since the width of the connecting portion is formed to be thinner than the width of each elastic contact portion, the connecting portion is easily elastically deformed, the elastic force generated by this connecting portion is increased, and each elastic portion is formed on the peripheral surface of the through hole. The contact portion is pressed strongly, and a sufficient retaining load is obtained, and a larger contact load is obtained.
[0045]
In addition, since a chamfered portion is formed at a connecting portion between each elastic contact portion and the connecting portion, stress concentration occurring at that portion can be reduced, and destruction due to the stress concentration is less likely to occur and durability is improved. Also excellent.
[0046]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the press-fit terminal which concerns on this invention, since the unnecessary rotational force which arises at the time of press-fitting into a through-hole of a printed circuit board can be reduced, the mounting component on a printed circuit board and its soldering part are damaged. And the likelihood of inconvenience such as giving Therefore, if this is used as a terminal when high connection reliability is required, for example, in an in-vehicle environment, its usefulness becomes extremely large.
[Brief description of the drawings]
FIG. 1 is a front view of a press-fit terminal according to an embodiment of the present invention.
FIG. 2 is a view showing an operation of inserting a press-fit terminal according to an embodiment of the present invention into a through hole of a printed circuit board.
FIG. 3 is an enlarged sectional view taken along line AA of FIG. 2;
FIG. 4 is a diagram showing a case where the length of a connecting portion in FIG. 3 is the shortest facing distance.
FIG. 5 is a view showing a case where the length of a connecting portion in FIG. 3 is the longest facing distance.
FIG. 6 is a view showing a state in which the press-fit terminal according to the embodiment of the present invention is inserted into a through hole of a printed circuit board.
FIG. 7 is an enlarged sectional view taken along the line BB of FIG. 6;
FIG. 8 is a diagram showing a cross-sectional shape of a press-fit connection portion in a solid-type press-fit terminal.
FIG. 9 is a diagram showing a cross-sectional shape of a conventional press-fit connection portion having an N-shaped cross-sectional shape.
FIG. 10 is a diagram showing a cross-sectional shape of a press-fit connection portion having another conventional N-shaped cross-sectional shape.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Press-fit terminal 12 Board connection part 13 Printed circuit board 14 Through-hole 16 Contact part 18 Elastic deformation part 18A Linear part 20 Press-fit connection part 21 Elastic contact part 22 Connection part 23 Outer part 24 Inner part C1, C2 Chamfer part

Claims (5)

In a press-fit terminal having a press-fit connection portion that is inserted into a through-hole of a printed circuit board and makes electrical contact with the through-hole, the press-fit connection portion is formed around a periphery of the through-hole when viewed in a cross section perpendicular to the longitudinal direction. A pair of elastic contact portions that are elastically contacted with the surface and face each other, and a connecting portion that is obliquely provided between the pair of elastic contact portions and whose both ends are connected to each elastic contact portion,
The press-fit terminal, wherein the connecting portion is formed to be longer than the shortest facing distance between the pair of elastic contact portions and shorter than the longest facing distance. The press-fit terminal according to claim 1, wherein a portion of each of the elastic contact portions that comes into contact with the through hole is formed to have a curvature substantially equal to a curvature of a peripheral surface of the through hole. The press-fit terminal according to claim 1, wherein a width of the connecting portion is formed to be thinner than a width of each of the elastic contact portions. The press-fit terminal according to any one of claims 1 to 3, wherein a chamfered portion is formed at a connecting portion between each of the elastic contact portions and the connecting portion. 5. The press-fit according to claim 1, wherein the press-fit connecting portion is formed in a substantially point-symmetrical shape with respect to a center of the connecting portion when viewed in a cross section perpendicular to the longitudinal direction. 6. Terminal.

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