JP4245253B2 - Conductive member - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a conductive member that is surface-mounted on a printed wiring board by a soldering process, presses an elastically deforming contact portion to a ground conductor, and grounds the printed wiring board to the ground conductor.
[0002]
[Prior art]
Conventionally, when a conductive member is surface-mounted on a printed wiring board, and the printed wiring board is fixed in that state, the conductive member is pressed against a grounding conductor such as a case so that the conductive pattern of the printed wiring board is formed via the conductive member. A technique of electrically connecting (grounding) to a ground conductor is known. In particular, in recent years, with the development of computer technology, many devices incorporating a microcomputer have been commercialized, and this is an indispensable technology for grounding a printed wiring board inside such a device.
[0003]
Many of such conductive members use a metal spring at the contact portion with the ground conductor. However, since the size of the conductive member itself is as small as several millimeters, the spring part may be caught by mistake during operation, and the spring part may be permanently deformed. In addition, the contact surface with the ground conductor may be peeled off and good grounding may not be achieved.
[0004]
Therefore, the present applicant has proposed a conductive member using a conductive elastomer for the contact portion (Japanese Patent Application No. 2000-103534). As shown in FIG. 5, a plate-like member 100 obtained by pressing a plated metal wire is prepared as the conductive member, and a liquid conductive elastomer 200 is formed on the upper surface 100b opposite to the joining surface 100a of the plate-like member 100. Is applied. In this conductive member, the conductive elastomer 200 comes into contact with the ground conductor and is elastically deformed to be pressed. Thus, unlike the case of using a metal spring, the disadvantages of using a metal spring, such as permanent deformation of the contact portion and peeling of the contact surface, can be eliminated, and good grounding can be achieved.
[0005]
[Problems to be solved by the invention]
However, the above-described conductive member also has room for improvement in the following points. That is two points: adhesive strength between the conductive elastomer 200 and the plate-like member 100 and height adjustment of the conductive elastomer 200.
[0006]
That is, if the conductive elastomer 200 is peeled off from the plate-like member 100, a pattern short circuit on the printed wiring board may be caused. Therefore, it is desirable to firmly fix a metal member such as the plate member 100 and a contact member such as the conductive elastomer 200.
[0007]
In the above-described technique, since the liquid conductive elastomer 200 is generally formed by coating, it is difficult to form a contact member such as the conductive elastomer 200 high. If the area of the metal member is increased, the contact member can be formed higher, but the conductive member itself becomes larger.
[0008]
The present invention has been made to solve the above-described problems, and is based on the premise of eliminating the drawbacks of using a metal spring, and can prevent the contact member from falling off from the metal member. An object of the present invention is to provide a conductive member in which the height of the member can be easily adjusted.
[0009]
[Means for Solving the Problems and Effects of the Invention]
The conductive member of the present invention includes a metal member and a contact member. The metal member has a thin bar shape and has a joint surface soldered to the conductor pattern of the printed wiring board. For example, a so-called rectangular wire obtained by pressing a plated metal wire may be used as the metal member. And the joint surface of this metal member is soldered, and a conductive member is mounted in a printed wiring board.
[0010]
When the printed wiring board is fixed at a predetermined position in a state where the conductive member is surface-mounted on the printed wiring board in this way, the contact member comes into contact with a ground conductor such as a main body case and is elastically deformed. As a result, the conductor pattern and the ground conductor are electrically connected.
[0011]
On the premise of such a configuration, the contact member is a columnar conductor, particularly in the first aspect of the invention. It is conceivable to employ a conductive elastomer as described above for the conductor. On the other hand, the metal member penetrates from one end portion to the other end portion of the contact member, and both end portions are folded back. And it has a joint surface in this folding | turning part.
[0012]
As described above, since the metal member is passed through the contact member such as a conductive elastomer, the contact member does not fall off from the metal member. Further, such a conductive member can be formed by forming a conductor through a metal member by so-called “extrusion molding”, cutting it to a predetermined length, and then folding back the tip of the metal member. Therefore, the height of the contact member can be easily adjusted depending on the shape of the die in the extrusion molding.
[0013]
However, it is conceivable that the conductor as the contact member is made of, for example, elastic rubber or polymer foam mixed with fine particles such as silver. Therefore, particularly when the height of the contact member is increased, the strength may be decreased.
Therefore, it is conceivable to employ the configuration shown in claim 2. The basic configuration of the present invention is the same as that of the first aspect of the present invention.
[0014]
Particularly in the present invention, the contact member has a columnar dielectric as a core material and a conductive layer laminated on the side surface of the dielectric. It is conceivable to use elastic rubber or polymer foam as the dielectric. In addition, it is conceivable that the conductive layer employs a conductive elastomer similar to the above-described conductor. At this time, the metal member penetrates from one end portion of the dielectric of the contact member to the other end portion, and both end portions are folded back. The folded portion has a joint surface and is in contact with the conductive layer at the folded portion.
[0015]
In this case as well, the above-described effects can be obtained. In this case, it is because the dielectric material which let the metal member pass can be formed by "extrusion molding", and a conductive layer can be coded after that. And since a dielectric is used as a core material, the strength of the contact member is also increased.
[0016]
Further, the folded portion of the metal member is in contact with the conductive layer, and a current flows through this contact portion, but generally the impedance increases as the frequency becomes higher. However, according to this configuration, the metal member and the conductive layer face each other with the dielectric interposed therebetween, and serve as a capacitor. Therefore, an increase in impedance when the frequency becomes high can be suppressed. This ensures good grounding.
[0017]
In addition, although the above is the structure which makes a metal member penetrate the contact member, you may comprise as shown in Claim 3.
The basic configuration of the present invention is the same as that of the above-described invention. In the present invention, the contact member is a columnar conductor, and the metal member has both tip portions folded back to the opposite side of the joint surface, and the contact member is sandwiched and held between the folded tip portions. Compared with the configuration described above, the contact member is more likely to be detached from the metal member. However, compared with the conventional configuration in which the liquid conductive elastomer is simply applied, the contact member and the metal member are also configured in this way. The bond becomes sufficiently strong. Furthermore, since the contact member can be formed by “extrusion molding”, the height of the contact member can be easily adjusted as in the above-described invention.
[0018]
Further, in order to increase the strength of the contact member, the configuration shown in claim 4 may be adopted. Also in this case, the basic configuration is the same as that of the above-described invention.
Here, in particular, the contact member has a columnar dielectric as a core material and a conductive layer laminated on the side surface of the dielectric. On the other hand, both end portions of the metal member are folded back to the opposite side of the joint surface, and the contact member is sandwiched and held between the folded both end portions, and part of the metal member is in contact with the conductive coating layer. Even if it does in this way, the effect similar to the invention of Claim 3 is acquired, and also the point that the intensity | strength of a contact member becomes high is advantageous.
[0019]
By the way, as shown in claim 5, the deformation degree of the contact member may be increased by forming a hollow portion inside the contact member. If the hollow portion is provided in this way, the contact pressure with the ground conductor can be adjusted without changing the material of the contact member. Thus, also when providing a hollow part in a contact member, it can form by "extrusion molding". Therefore, the height of the contact member can be easily adjusted.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
FIG. 1A is a perspective view showing the conductive member 1 of the first embodiment, and FIG. 1B is a front view of the conductive member 1.
[0021]
The conductive member 1 of this embodiment includes a metal member 10 and a contact member 20.
The metal member 10 is a thin bar member having a cross-sectional dimension of about 0.8 to 1 mm × about 0.3 to 0.5 mm, for example. For example, it is conceivable to form a tin-plated copper metal wire by pressing it from the side. A pre-made rectangular wire may be used. The reason for plating the wire is to ensure good soldering. In that sense, in addition to tin, the wire may be plated with nickel, gold, silver, or the like.
[0022]
On the other hand, the contact member 20 is obtained by laminating a conductive layer 21 on a side surface of a columnar dielectric 22 as a core material. The conductive layer 21 is a material having conductivity and elasticity, such as an elastic rubber such as silicone rubber or a polymer foam such as chloroprene, neoprene, samptoprene, and polyurethane, and silver, copper, aluminum, nickel, carbon, graphite, etc. It is a mixture of fine particles. Since the dielectric 22 is an elastic material, it is formed of an elastic rubber such as silicone rubber, or a polymer foam such as chloroprene, neoprene, samptoprene, or polyurethane.
[0023]
With respect to the contact member 20 formed in a columnar shape, the metal member 10 penetrates from one end portion of the dielectric 22 to the other end portion, and both end portions of the metal member 10 are folded back. The lower surface of the folded portion is a joint surface 10a. The upper surface 10 b opposite to the joint surface 10 a at the folded portion is in contact with the conductive layer 21. Thereby, the metal member 10 and the contact member 20 are electrically connected.
[0024]
For example, the conductive member 1 is manufactured as follows. First, the dielectric 22 through the metal member 10 is formed by “extrusion molding”, and the conductive layer 21 is further coated. And after cutting | disconnecting to predetermined length, only the contact member 20 is further cut | disconnected so that both the front-end | tip parts of the metal member 10 may be exposed, and the front-end | tip part of the metal member 10 is turned back.
[0025]
The conductive member 1 configured in this manner is soldered to the conductor pattern of the printed wiring board at the joint surface 10a. When the printed wiring board is fixed at a predetermined position in this state, the contact member 20 comes into contact with a grounding conductor such as a main body case and is elastically deformed to be in pressure contact. This electrically connects the conductor pattern of the printed wiring board and the ground conductor.
[0026]
In the conductive member 1 of this embodiment, since the contact member 20 that is in pressure contact with the ground conductor is formed of the conductive layer 21 and the dielectric 22 having elasticity, the disadvantages in the case of using a metal spring can be solved. That is, the conductive member is not deformed by catching the spring part during the operation, and the contact surface with the ground conductor is not peeled off.
[0027]
In addition, since the metal member 10 is passed through the dielectric 22 of the contact member 20, the contact member 20 does not fall off the metal member 10. Further, since the dielectric 22 through the metal member 10 can be formed by “extrusion molding”, the height of the contact member 20 can be easily adjusted.
[0028]
By the way, the upper surface 10b of the folded portion of the metal member 10 is in contact with the conductive layer 21, and the metal member 10 and the contact member 20 are electrically connected at this contact portion. Therefore, a current usually flows through this contact portion. However, the impedance generally increases as the frequency increases.
[0029]
On the other hand, in the present conductive member 1, as shown in FIG. 1B, the conductive layer 21 and the metal member 10 are disposed so as to face each other with the dielectric 22 interposed therebetween, and thus the role as a capacitor is achieved. Fulfill. Therefore, an increase in impedance when the frequency becomes high can be suppressed. This ensures good grounding.
[0030]
Further, in the present conductive member 1, the conductive layer 21 is laminated (coated) on the dielectric 22 as the core material, and therefore, compared with the case where the contact member 20 is formed only by a conductor mixed with fine particles such as silver. The strength of the contact member 20 is increased. In addition, you may form the contact member 20 whole with the conductor which has electroconductivity and elasticity. Although the strength is somewhat lowered, even in this case, the contact member 20 can be prevented from falling off the metal member 10, and the height of the contact member 20 can be easily adjusted.
[Second Embodiment]
FIG. 2A is a perspective view showing the conductive member 3 of the second embodiment, and FIG. 2B is a front view of the conductive member 3.
[0031]
The conductive member 3 of the present embodiment includes a metal member 30 and a contact member 40.
The metal member 30 is a thin bar-like member similar to the metal member 10 of the first embodiment, and is configured by using, for example, an established rectangular wire.
Similarly to the first embodiment, the contact member 40 is also formed in a columnar shape by laminating a conductive layer 41 on the side surface of the dielectric 42.
[0032]
In the present embodiment, the metal member 30 holds the contact member 40 such that both ends are folded back and the both ends of the columnar dielectric 42 are sandwiched between the folded-back opposing ends 30b. The metal member 30 has a lower surface of the central portion as a bonding surface 30a with the printed wiring board, and is in contact with the conductive layer 41 on an upper surface 30c opposite to the bonding surface 30a. Thereby, the metal member 30 and the contact member 40 are electrically connected.
[0033]
The conductive member 3 is manufactured as follows, for example. First, the dielectric 42 is formed by “extrusion”, and the conductive layer 41 is further coated. And after cutting | disconnecting to predetermined length, both the front-end | tip parts of the metal member 30 cut | disconnected together are turned back, and it fixes so that the contact member 40 may be inserted | pinched with the front-end | tip 30b.
[0034]
The conductive member 3 configured in this manner is soldered to the conductor pattern of the printed wiring board at the joint surface 30a. When the printed wiring board is fixed at a predetermined position in this state, the contact member 40 comes into contact with a grounding conductor such as a main body case and is elastically deformed to be in pressure contact. This electrically connects the conductor pattern of the printed wiring board and the ground conductor.
[0035]
In the conductive member 3 of the present embodiment, since the contact member 40 that is pressed against the ground conductor is formed of the elastic conductive layer 41 and the dielectric 42, the disadvantages in the case of using a metal spring are eliminated as in the first embodiment. can do.
In addition, since both the front end portions of the metal member 30 are folded back and the contact member 40 is sandwiched between the front ends 30b, the contact member 40 can be prevented from falling off from the metal member 30. Further, since the dielectric 42 can be formed by “extrusion molding”, the height of the contact member 40 can be easily adjusted.
[0036]
Also in this conductive member 3, as in the first embodiment, since the conductive layer 41 is laminated on the dielectric 42 as the core material, the contact member 40 can be formed only by a conductor mixed with fine particles such as silver. Compared with the case where it forms, the intensity | strength of the contact member 40 becomes high. In addition, you may form the contact member 40 whole with the conductor which has electroconductivity and elasticity. This is because the contact member 40 can be prevented from falling off the metal member 30 although the strength is somewhat lowered, and the height adjustment of the contact member 40 is facilitated.
[Third embodiment]
FIG. 3A is a perspective view showing the conductive member 5 of the third embodiment, and FIG. 3B is a front view of the conductive member 5.
[0037]
The conductive member 5 of this example includes a metal member 50 and a contact member 60.
Since the metal member 50 and the contact member 60 are made of the same material as in the first and second embodiments, description thereof is omitted. The metal member 50 penetrates the contact member 60 formed in a columnar shape from one end of the dielectric 62 to the other end, and both ends of the metal member 50 are folded back. The lower surface of the folded portion is a joint surface 50a. The upper surface 50 b opposite to the bonding surface 50 a is in contact with the conductive layer 61. Thereby, the metal member 50 and the contact member 60 are electrically connected.
[0038]
Further, in this embodiment, a hollow portion parallel to the metal member 50 is formed in the dielectric 62 in the upper portion of the metal member 50 that penetrates the inside of the dielectric 62.
The conductive member 5 is manufactured, for example, as follows. First, the dielectric 62 passed through the metal member 50 is formed by “extrusion molding”, and the conductive layer 61 is further coated. At this time, a hollow portion is also formed by the shape of the base. And after cutting | disconnecting to predetermined length, only the contact member 60 is further cut | disconnected so that both the front-end | tip parts of the metal member 50 may be exposed, and the front-end | tip part of the metal member 50 is turned back.
[0039]
The conductive member 5 configured as described above is soldered to the conductor pattern of the printed wiring board at the joint surface 50a. In this state, when the printed wiring board is fixed at a predetermined position, the contact member 60 comes into contact with a ground conductor such as a main body case and is elastically deformed to be in pressure contact. At this time, since there is a hollow portion, the amount of elastic deformation increases. This electrically connects the conductor pattern of the printed wiring board and the ground conductor.
[0040]
In the conductive member 5 of the present embodiment, since the contact member 60 is formed by the conductive layer 61 and the dielectric 62 having elasticity, it is possible to eliminate the drawbacks when using a metal spring, as in the first and second embodiments. it can. In addition, the contact member 60 does not fall off the metal member 50 because the metal member 50 is penetrated, and the height of the contact member 60 can be easily adjusted because it can be formed by “extrusion molding”. It is the same as that of an Example. Further, as shown in FIG. 3B, since the conductive layer 61 and the metal member 50 are arranged so as to face each other with the dielectric 62 and the hollow portion interposed therebetween, the impedance rise when the frequency becomes high. It can also be suppressed.
[0041]
In addition, since the hollow portion is provided in the dielectric 62, the degree of deformation of the contact member 60 is increased, and the contact pressure to the ground conductor is reduced without changing the material constituting the contact member 60. That is, the contact pressure can be changed by appropriately changing the size and position of the hollow portion.
[0042]
Note that the strength of the contact member 60 is increased by using the dielectric 62 as the core material. Also at this time, the entire contact member 60 may be formed of a conductive material having conductivity and elasticity. This is because the contact member 60 can be prevented from falling off the metal member 50, although the strength is somewhat lowered, and the height adjustment of the contact member 60 is facilitated.
[Others]
(A) In the first to third embodiments, the conductive layers 21, 41, 61 are made of a material in which fine particles such as silver are mixed into elastic rubber or a polymer foam, but a conductive cloth may be used, for example. Good. In this case, it is conceivable that dielectrics 22, 42, 62 such as silicone rubber are formed and then wound. Further, a metal foil or a metal net can be used for the conductive layer. These may be properly used according to the use environment.
[0043]
In the first to third embodiments, the conductive layers 21, 41, 61 are laminated (coated) only on the side surfaces of the contact members 20, 40, 60. You may make it coat. In this case, after the extruded dielectrics 22, 42, 62 are cut, in the first and third embodiments, the tips of the metal members 10, 50 are further exposed, and then the coding is performed. Good.
[0044]
(B) Further, in the second embodiment, the configuration in which the contact member 40 is sandwiched and fixed by the both side tips 30b of the metal member 30 is shown. At this time, the entire lower surface of the metal member 30 is used as the joint surface 30a. However, for example, as shown in FIG. 4A, the center portion of the metal member 70 may be bent upward to provide two joint surfaces 70a. Conceivable. In this way, even if the printed wiring board is bent, the stress applied to the soldered portion is reduced, and the conductive member can be prevented from being detached from the conductor pattern. Further, the height of the conductive member can be adjusted by the metal member 70. Note that three or more joining surfaces may be provided.
[0045]
(C) Furthermore, in the second embodiment, the tip 30b of the metal member 30 is inserted into the dielectric 42 from both ends to fix the contact member 40. For example, as shown in FIG. It is also conceivable that a convex portion 80a is provided below the end of the contact member 80, and the contact member 80 is held such that the tip 30b is hooked on the convex portion 80a.
[Brief description of the drawings]
FIG. 1A is a perspective view of a conductive member of a first embodiment, and FIG. 1B is a front view.
FIG. 2A is a perspective view of a conductive member of a second embodiment, and FIG. 2B is a front view.
FIG. 3A is a perspective view of a conductive member according to a third embodiment, and FIG. 3B is a front view.
FIG. 4 is an explanatory view showing a modification of the second embodiment.
FIG. 5 is an explanatory view showing a conventional conductive member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, 3, 5 ... Conductive member 10, 30, 50, 70 ... Metal member 20, 40, 60, 80 ... Contact member 10a, 30a, 50a, 70a ... Joining surface 10b, 30c, 50b ... Upper surface 30b ... Tip 21, 41, 61 ... conductive layers 22, 42, 62 ... dielectric 80a ... convex portion 100 ... plate member 100a ... bonding surface 100b ... upper surface 200 ... conductive elastomer

Claims (5)

A thin bar metal member having a joint surface soldered to the conductor pattern of the printed wiring board, and grounding by fixing the printed wiring board in place with the joint surface soldered to the conductor pattern A conductive member that contacts the conductor and elastically deforms, and electrically connects the conductive pattern and the ground conductor;
The contact member is a columnar conductor,
The conductive member is characterized in that the metal member penetrates from one end portion to the other end portion of the contact member, both end portions are folded back, and the joint surface is provided at the folded portion. A thin bar metal member having a joint surface soldered to the conductor pattern of the printed wiring board, and grounding by fixing the printed wiring board in place with the joint surface soldered to the conductor pattern A conductive member that contacts the conductor and elastically deforms, and electrically connects the conductive pattern and the ground conductor;
The contact member has a columnar dielectric as a core material, and a conductive layer laminated on a side surface of the dielectric,
The metal member penetrates from one end portion to the other end portion of the dielectric of the contact member, both end portions are folded back, the folded portion has the joint surface, and the folded portion is electrically conductive. A conductive member in contact with the layer. A thin bar metal member having a joint surface soldered to the conductor pattern of the printed wiring board, and grounding by fixing the printed wiring board in place with the joint surface soldered to the conductor pattern A conductive member that contacts the conductor and elastically deforms, and electrically connects the conductive pattern and the ground conductor;
The contact member is a columnar conductor,
Both ends of the metal member are folded back to the opposite side of the joint surface, and the contact member is sandwiched and held by the folded both ends. A thin bar metal member having a joint surface soldered to the conductor pattern of the printed wiring board, and grounding by fixing the printed wiring board in place with the joint surface soldered to the conductor pattern A conductive member that contacts the conductor and elastically deforms, and electrically connects the conductive pattern and the ground conductor;
The contact member has a columnar dielectric as a core material, and a conductive layer laminated on a side surface of the dielectric,
Both ends of the metal member are folded back to the opposite side of the joining surface, the contact member is sandwiched and held by the folded both ends, and a part of the metal member is in contact with the conductive coating layer. Conductive member. In the electrically-conductive member in any one of Claims 1-4,
A conductive member, wherein a degree of deformation of the contact member is increased by forming a hollow portion inside the contact member.

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