JPH1175279A - Small sized microphone assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small sized microphone assembly which is assembled by pressing the small sized microphone assembly into contact with an electrode of a printed circuit board by integrating a small sized microphone, a vibration proof rubber forming covering the microphone and an anisotropic conductive rubber connector and where soldering and lead wire arrangement are omitted. SOLUTION: The surrounding of a small sized microphone 11 is covered by a vibration proof rubber mold 12, and an anisotropic conductive rubber connector 13 where a conductive layer 14 and an electric insulation layer are laminated alternately is clipped in face contact with an electrode 15 of the small sized microphone 11 so as to integrate the small sized microphone 11, the vibration proof rubber mold 12 and the anisotropic conductive rubber connector 13. In this case, the rubber connector 13 is processed to be a shape by which one conductor layer 14 of the rubber connector 13 is not simultaneously in contact with pluralities of the electrodes 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a small microphone assembly suitable for being incorporated in a main body of a small communication device represented by a portable telephone and a portable radio device.

[0002]

2. Description of the Related Art At present, small portable communication devices are mainly developed to be smaller and lighter in weight, and a microphone element body used as one component thereof is becoming smaller. Among them, the mounting of a small microphone involves soldering a thin lead wire to connect the electrode on the small microphone side to the electrode on the circuit board inside the small communication device body, and then using a rubber molded product as a waterproof seal. The one covered by a small microphone is built into a small communication device.

[0003]

However, the method of assembling a small microphone for soldering a thin lead wire is as follows.
There are problems that the soldering work is fine, automation of the work is difficult and manual work is difficult, and thus the quality is lacking in stability, and that the mounting space cannot be narrowed because the lead wires are provided.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention provides an anisotropic conductive rubber connector for a mounting method capable of simplifying an assembling operation by eliminating a soldering operation and extremely reducing a mounting space. It is an object to provide a used small microphone assembly.

[0005]

In order to achieve the above object, a small microphone assembly using an anisotropic conductive rubber connector according to the present invention covers the small microphone with a vibration-proof rubber molded product, and has a conductive property. Anisotropic conductive rubber connector (hereinafter, also referred to as a “zebra-type anisotropic conductive rubber connector”) in which a layer and an electrical insulating layer are laminated is sandwiched and fixed so as to make surface contact with the electrode portion of the small microphone. It is characterized in that a rubber molded product for vibration isolation which covers this and the anisotropic conductive rubber connector are integrated. According to this configuration, the small microphone assembly of the present invention can be assembled simply by pressing against the electrode portion on the circuit board, and the soldering operation and the operation of arranging the lead wires can be omitted. Also, the mounting space can be reduced.

In the above configuration, it is preferable that the anisotropic conductive rubber connector is configured such that one conductive layer does not simultaneously contact two or more electrodes of the small microphone. If the same conductive layer contacts two or more electrodes at the same time, a short circuit occurs between the electrodes and the small microphone does not operate normally.

In the above construction, it is preferable that the rubber molded product for vibration isolation is made of silicone rubber. This is because it has high durability and excellent vibration damping properties.

In the above construction, the rubber member of the anisotropic conductive rubber connector includes polybutadiene, natural rubber, polyisoprene, styrene-butadiene copolymer rubber (SBR), and butadiene-acrylonitrile copolymer rubber (NBR). , Ethylene-propylene-non-conjugated diene copolymer (EPDM), ethylene-propylene copolymer (EPM), polyurethane polyester rubber, chloroprene rubber, epichlorohydrin rubber, and silicone rubber. Silicone rubber is most preferred.

In the above construction, the conductive layer of the zebra-type anisotropic conductive rubber connector may be composed of platinum, gold, silver, nickel, cobalt, copper, tin, and 100 parts by weight of the rubber component.
At least one fine powder selected from aluminum, palladium-containing metal powder, solder-containing alloy fine powder, conductive fine powder of organic polymer fine powder coated with metal, and conductive fine powder of inorganic fine powder coated with metal. From 1 to 400
10 to 150 parts by weight, especially 40 to 100 parts by weight, based on 100 parts by weight of the conductive rubber or rubber component added and blended in the range of 100 to 300 parts by weight, particularly 100 to 300 parts by weight.
It is preferable that the conductive rubber is formed of a conductive rubber added and blended in a range of parts by weight. If the amount of the fine powder or carbon black is less than the above range, good conductivity cannot be obtained. Conversely, if the amount of the fine powder or carbon black is more than the above range, not only does the conductivity not improve much, but also the moldability and compression elasticity of the rubber connector are impaired.

In the above structure, it is preferable that the zebra type anisotropic conductive rubber connector has a compressive elasticity and can be assembled by being brought into surface contact with the electrode portion on the circuit board. Since the rubber connector has compression elasticity, when the small microphone assembly is incorporated in a small communication device or the like, the rubber connector is compressed between the electrode of the small microphone and the electrode of the circuit board, and is appropriately elastically deformed. This ensures that the rubber connector is in surface contact with both electrode surfaces. As a result, the reliability of the electrical connection is improved. Further, the small microphone is elastically held together with the rubber molded product for vibration proof, thereby improving the vibration resistance of the small microphone.

The compression elasticity of the rubber part at this time is determined according to JIS.
In the method A of K6301, it is preferably in the range of 30 to 80. If the compression elasticity is smaller than the above range, the elastic deformation of the rubber connector becomes large, pressure-sensitive conductivity is generated, and the electrical connection resistance value with the circuit board electrode becomes unstable.
On the other hand, if the compression elasticity is larger than the above range, the elastic deformation of the rubber connector is small, so that the reliability of the electrical connection with the circuit board electrode may be reduced. JIS K6
The measurement of the compression elasticity described in Method A of 301 is as follows. As a sample, a test piece having a size specified in JIS K6301 is prepared and used as a sample. The measuring tool is JIS K
Use an A-type spring hardness tester conforming to 6301. The method A of JIS K6301 is based on ASTM D2
240 type A.

Although the small microphone assembly of the present invention is used for various purposes, it is preferable that the microphone assembly is used by being incorporated in the main body of a small portable communication device such as a portable telephone. The small microphone assembly of the present invention eliminates the need for soldering work using lead wires, thereby reducing the mounting space, and the small microphone body is pressed and held between a rubber molded product for vibration isolation and a rubber connector. By doing so, the reliability and vibration resistance of the electrical connection are improved at the same time, so that the commercial value of a small portable communication device that is particularly required to be reduced in size and improved in reliability can be improved.

In the small microphone assembly using the zebra type anisotropic conductive rubber connector having the above-described configuration, the zebra type anisotropic conductive rubber connector is provided on the electrode surface of the small microphone and on the circuit board in the small communication device main body. A highly reliable electrical connection can be made only by lightly compressing the surface with the electrode surface. Further, the zebra type anisotropic conductive rubber connector is conductive only in the thickness direction of the rubber connector, and is insulated in the laminating direction of the zebra portion (the portion where the conductive layer and the electrical insulating layer are laminated on each other). In addition to having the property, it is possible to obtain a highly reliable electrical connection by making the conductive layer of the zebra part not contact two or more electrodes at the same time, and it is necessary to align complicated rubber connectors do not do. Moreover, since a plurality of circuits can be connected by one rubber connector, circuit connection for soldering lead wires is not required, so that not only the mounting space can be reduced, but also a troublesome mounting operation can be omitted.

In addition, a rubber molded product called a bush for vibration damping covers all parts other than the electrode surface and the sound collecting part of the small microphone in a gas-tight manner, and simultaneously sandwiches a zebra type anisotropic conductive rubber connector in surface contact with the electrode. By having a shape that can be fixed, the small microphone and the zebra-type anisotropic conductive rubber connector can be integrated. As a result, it is possible to mount a small microphone simply by incorporating a small microphone assembly using a zebra-type anisotropic conductive rubber connector into a predetermined location in a small communication device, and to greatly improve the efficiency of assembly work. Can be done.

In addition, by using a rubber molded product for vibration isolation called a bush, not only the vibration isolation reliability of the small microphone but also the microphone in the small communication device in which the small microphone assembly is incorporated. Since the surface pressure between the electrode surface and the circuit substrate electrode surface is held at a constant pressure by the rubber elasticity of the bush, a synergistic effect that a highly reliable electrical connection can be achieved is exhibited.

[0016]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

FIG. 1A (plan view), FIG. 1B (I-
1C (bottom view), in one embodiment shown in FIG. 1C (bottom view), the small microphone assembly 1 includes a small condenser microphone body 11, a zebra type anisotropic conductive rubber connector 13, and a rubber for vibration isolation called a bush. And a molded product 12. The size of the small microphone assembly is 6-10m in diameter
m, height 2-5 mm. The thickness of the rubber molded product 12 for vibration isolation is about 0.9 mm. The thickness of the zebra type anisotropic conductive rubber connector 13 is about 1.0 mm.

As is apparent from FIG. 1C (bottom view), the zebra-type anisotropic conductive rubber connector 13 is processed into a shape such that the conductive layer 14 of the zebra portion does not simultaneously contact the two electrodes 15.

FIGS. 2, 3 and 4 (bottom views) show another embodiment, in which a zebra type anisotropic conductive rubber connector 23,
The conductive layers 24, 34, 44 of the zebra portions 33, 43 are respectively processed into shapes that do not simultaneously contact the two electrodes 25, 35, 45. Note that reference numerals 2, 3, and 4
Represents a small microphone assembly, numerals 21, 31, and 41 represent small condenser microphone bodies, and numerals 22, 32, and 4
Reference numeral 2 denotes a rubber molded product for vibration isolation.

FIG. 5 (perspective view) shows a zebra type anisotropic conductive rubber connector 53 in which conductive layers 54 made of conductive silicone rubber and electric insulating layers 56 made of insulating silicone rubber used in the above embodiment are alternately laminated. Specifically, for example, a zebra-type anisotropic conductive rubber connector “Fujipoly Connector Z Series” using a conductive silicone rubber containing carbon fine particles as a conductive member.
(Manufactured by Fuji Kogaku Kogyo Co., Ltd.) or a zebra-type anisotropic conductive rubber connector “Fuji Poly Connector S-Z Series” using conductive silicone rubber containing fine metal powder as a conductive member (Fuji Kogaku Kogyo ( Co., Ltd.) can be used. This zebra type anisotropic conductive rubber connector 13, 2
Each of 3, 33 and 43 preferably has a thickness of about 1 to 2 mm and a lamination pitch of zebra parts of about 0.05 to 0.50 mm.

Further, as a rubber molded product for vibration isolation called a bush, for example, a zebra-type anisotropic conductive rubber connector which covers all parts other than the electrode surface and the sound collecting part of a small microphone in an airtight manner and which comes into surface contact with the electrode. Rubber molded product "Fujipoly M Mold 4EC Bush" having a shape that can also be clamped and fixed at the same time (Fuji Polymer Industry Co., Ltd.)
Manufactured) can be used.

After the rubber molded product for vibration isolation is mounted on the small microphone, the rubber connector is fitted into the rubber molded product on the electrode surface side of the small microphone. Thus, the rubber connector is sandwiched and fixed by the elastic force of the rubber molded product for vibration isolation in a state of being in surface contact with the electrode portion of the small microphone. Thus, a small microphone assembly in which the small microphone, the rubber molded product for vibration isolation, and the rubber connector are integrated is obtained.

In order to mount the small microphone assembly, the mounting operation is completed only by incorporating the zebra type anisotropic conductive rubber connector into the small communication device main body so as to be in pressure contact with the electrode portion on the circuit board. In addition, the work efficiency in the assembling work can be greatly improved, the mounting space can be minimized, and highly reliable electrical connection can be achieved.

Examples of the rubber material of the zebra-type anisotropic conductive rubber connector include polybutadiene, natural rubber, polyisopropylene, SBR, NBR, EPDM, EPM, polyurethane polyester rubber, chloroprene rubber, epichlorohydrin rubber, and silicone rubber. But
Silicone rubber is most preferred from the viewpoint of electrical insulation and weather resistance.

The conductive layer of the zebra-type anisotropic conductive rubber connector is composed of platinum, gold,
Metal powder containing silver, nickel, cobalt, copper, tin, aluminum, palladium, alloy fine powder containing solder, conductive fine powder obtained by coating organic polymer fine powder with metal, and conductive powder obtained by coating inorganic fine powder with metal At least one fine powder selected from fine powder is added to the conductive rubber in the range of 1 to 400 parts by weight, and the rubber is 100 parts by weight,
It is preferable that the conductive rubber is formed of a conductive rubber in which carbon fine powder is added and blended in a range of 10 to 150 parts by weight.

[0026]

As described above, according to the small microphone assembly using the zebra type anisotropic conductive rubber connector of the present invention, the zebra type anisotropic conductive rubber connector is connected to the electrode surface of the small microphone and the main body of the small communication device. A highly reliable electrical connection can be made only by lightly compressing the surface with the electrode surface on the internal circuit board. In addition, the zebra type anisotropic conductive rubber connector has anisotropic conductivity that conducts only in the thickness direction of the rubber connector and insulates in the laminating direction of the zebra part, and has two or more conductive layers of the zebra part at the same time. In this case, a highly reliable electrical connection can be obtained, and complicated rubber connector alignment is not required. Moreover,
Since a plurality of circuits can be connected by one rubber connector, circuit connection for soldering lead wires is not required, so that not only the mounting space can be reduced, but also a troublesome mounting operation can be omitted.

In addition, a rubber molded product for vibration isolation called a bush covers all parts of the small microphone other than the electrode surface and the sound collecting portion in an airtight manner, and simultaneously sandwiches a zebra type anisotropic conductive rubber connector in surface contact with the electrode. By having a shape that can be fixed, the small microphone and the zebra-type anisotropic conductive rubber connector can be integrated. As a result, it is possible to mount a small microphone simply by incorporating a small microphone assembly using a zebra-type anisotropic conductive rubber connector into a predetermined location in a small communication device, and to greatly improve the efficiency of assembly work. Can be done.

In addition, by using a rubber molded product for vibration isolation called a bush, not only the vibration isolation reliability of the small microphone but also the microphone in the small communication device in which the small microphone assembly is incorporated. Since the surface pressure between the electrode surface and the circuit substrate electrode surface is held at a constant pressure by the rubber elasticity of the bush, a synergistic effect that a highly reliable electrical connection can be achieved is exhibited.

[Brief description of the drawings]

1A is a plan view of a small microphone assembly according to an embodiment of the present invention, FIG. 1B is a cross-sectional view of FIG. 1A as viewed from the direction of the arrow II, and FIG. 1C is a bottom view thereof.

FIG. 2 shows a bottom view of a miniature microphone assembly according to another embodiment of the present invention.

FIG. 3 shows a bottom view of a miniature microphone assembly according to another embodiment of the present invention.

FIG. 4 shows a bottom view of a miniature microphone assembly according to another embodiment of the present invention.

FIG. 5 is a perspective view of an embodiment of a zebra type anisotropic conductive rubber connector used in the present invention.

[Explanation of symbols]

1, 2, 3, 4 Small microphone assembly 11, 21, 31, 41 Small condenser microphone main body 12, 22, 32, 42 Rubber molded product for vibration isolation 13, 23, 33, 43 Zebra type anisotropic conductivity Rubber connector 14, 24, 34, 44 Zebra conductive layer 15, 25, 35, 45 Electrode 53 Zebra type anisotropic conductive rubber connector 54 Conductive layer 56 Electrical insulating layer

Claims (10)

[Claims] 1. An anisotropic conductive rubber connector in which a small microphone is covered with an anti-vibration rubber molded product and a conductive layer and an electrical insulating layer are laminated and fixed so as to be in surface contact with the electrode portion of the small microphone. A small microphone assembly wherein the small microphone, a rubber molded product for vibration isolation covering the small microphone, and the anisotropic conductive rubber connector are integrated. 2. The small microphone assembly according to claim 1, wherein the anisotropic conductive rubber connector is configured such that one conductive layer does not simultaneously contact two or more electrodes of the small microphone. 3. The small microphone assembly according to claim 1, wherein the rubber molded product for vibration isolation is made of silicone rubber. 4. The rubber member of the anisotropic conductive rubber connector,
The small microphone assembly according to claim 1, wherein the microphone assembly is made of silicone rubber. 5. The conductive layer of the anisotropic conductive rubber connector includes a metal powder containing platinum, gold, silver, nickel, cobalt, copper, tin, aluminum, palladium, and solder, based on 100 parts by weight of the rubber component. Claims: At least one fine powder selected from an alloy fine powder, a conductive fine powder having a metal coating on an organic polymer fine powder, and a conductive fine powder having a metal coating on an inorganic fine powder, in a range of 1 to 400 parts by weight. Item 2. A small microphone assembly according to Item 1. 6. The conductive layer of the anisotropic conductive rubber connector has a carbon content of 10 to 10 parts by weight of a rubber component.
2. The miniature microphone assembly of claim 1 including a range of 150 parts by weight. 7. The small microphone assembly according to claim 1, wherein the anisotropic conductive rubber connector has a compression elasticity, and can be assembled by being brought into surface contact with an electrode portion on the circuit board. 8. The compression elasticity of the anisotropic conductive rubber connector is as follows:
2. The small microphone assembly according to claim 1, wherein in the A method of JIS K6301, the range is 30 to 80. 3. 9. The small microphone assembly according to claim 1, wherein the small microphone assembly is a small microphone assembly incorporated in a main body of the small portable communication device.
The small microphone assembly described in 1. 10. The small microphone assembly according to claim 9, wherein the small portable communication device is a mobile phone.