KR20070006293A - Electret microphone include washer spring - Google Patents

Abstract

An electret microphone including a washer spring is provided to operate normally by using the washer spring even though an error is generated in a manufacturing process. In an electret microphone including a washer spring, a spacer(5) is located between a diaphragm(3) and a back electret(6) to insulate the diaphragm(3) from the back electret(6). The back electret(6) and the diaphragm(3) form a static electricity. A first base ring(8) is located between the back electret(6) and the case(1) to insulate the back electret(6) from the case(1). A second base ring(9) is accepted inside the first base ring(8) to insulate the back electret(6) from the printed circuit board(10). A printed circuit board(10) is provided with an electrical signal from one of the diaphragm(3) and the back electret(6). And, the washer spring(2) provides an elastic force between inner received objects, the case(1), and the printed circuit boards(10).

Description

Electret Microphone Include Washer Spring with Washer Spring

1 is a view showing a back-type electret condenser microphone according to a first embodiment of the present invention.

2 is a cross-sectional view showing an assembled cross-section of the bag type electret condenser microphone of FIG.

3 shows the shape of the washer spring of FIGS. 1 and 2;

4 is a diagram illustrating various examples of the washer spring of FIG. 3.

5 is a cross-sectional view of an ECM according to a second embodiment of the present invention.

6 is a cross-sectional view of an ECM according to a third embodiment of the present invention.

7 is a view showing still another example of the foil-type ECM according to the fourth embodiment of the present invention.

8 is a sectional view showing a cross section of an ECM according to a fifth embodiment according to the present invention;

<Description of the symbols for the main parts of the drawings>

1, 31, 51, 61, 71: case

2, 22, 23, 24, 25, 32, 52, 62, 72: washer spring

3, 33, 53, 63, 73: diaphragm

5, 35, 55, 65, 75: spacer

6, 36, 56, 66, 76: double plate

8, 38, 58, 68, 78: first base ring

9, 39, 59, 69, 79: second base ring

10, 40, 60, 70, 80: printed circuit board

11, 41, 54, 64, 74: sound hole

12, 42, 57, 67, 77: circuit element

The present invention relates to a condenser microphone, and more particularly, to a condenser microphone capable of improving normal operation and manufacturing yield.

Recently, multimedia devices that are commonly encountered in the surroundings, such as moving picture experts group layer 3 (MP3), camcorders, and mobiles, are capable of recording sound generated from the surroundings. This is universally provided. In particular, one of the main reasons why such a recording function can play a role in the miniaturized and high-performance multimedia devices is a microphone that is miniaturized and mounted inside the multimedia device.

Such a microphone is typically represented by a dynamic microphone using a magnet and a condenser microphone using a principle of a capacitor (or a capacitor, a capacitor, or a capacitor). In the case of a dynamic microphone, an induced electromotive force is used to store a magnet capable of forming a constant magnetic field (or magnetic field) inside the microphone. In addition, the coil is connected to the diaphragm and flows inside the magnetic field. This dynamic microphone is a principle that measures the induced electromotive force generated when the coil shakes inside the magnetic field due to vibration and converts it into an electrical signal. This dynamic microphone has a mechanically strong characteristic, which is advantageous for use in harsh environments, but it is difficult to miniaturize because the magnet must be housed inside the microphone, and it has a poor sensitivity characteristic and a slow response speed compared to the condenser microphone. have.

On the other hand, in the case of condenser microphones, mechanical robustness is inferior to that of dynamic microphones, but it is relatively easy to miniaturize, and has excellent sensitivity characteristics and transfer speed. These condenser microphones are classified into omnidirectional condenser microphones and directional condenser microphones according to their directivity characteristics, and are further divided into bidirectional single-directional condenser microphones according to their directivity characteristics.

In the condenser microphone, an electric field is formed by the diaphragm and the bipolar plate, and the formed electric field uses the principle of converting the amount of the electric field that changes with the vibration of the diaphragm into an electrical signal. To this end, the condenser microphone must be supplied with power to either the diaphragm or the bipolar plate to form an electric field. For this reason, a method of supplying power to the bipolar plate has been used, and condenser microphones have been developed in recent years by an electret in which charges are accumulated.

The condenser microphone using this electret is called an electret condenser microphone ("ECM"), and is classified into a front type and a back type according to the positions of the electret and the diaphragm. do. The front type and the back type are merely different positions of the dielectric plate having the electret and the diaphragm, and the operation principle is the same.

ECM is becoming smaller due to the adoption of electrets, and many technologies are being developed. The ECM is used in a form in which a diaphragm, a dielectric plate, a spacer ring, an insulator and a conductive base ring printed circuit board (hereinafter referred to as "PCB") are sequentially stacked in a cylindrical case in which one surface is blocked. Sound holes are formed in the blocked portion of the cylindrical case, and vibrations generated by voice are transmitted through the sound holes. When the diaphragm, the spacer ring, and the base ring are accommodated in the cylindrical case, the remaining portion of the cylindrical case is bent and sealed, or the size of the PCB is increased to produce an ECM in the form of coupling with the case. In this case, a solder ball for applying a Surface Mount Devices (SMD) method is attached to a portion exposed to the outside of the PCB, or a terminal for connection with a mother substrate is formed. The ECM with solder balls or terminals is attached to the mother substrate by the SMD process or the soldering process.

On the other hand, ECM uses relatively low precision components in consideration of manufacturing cost and productivity. As a result, there is a tolerance (or error) due to the manufacturing process between the diaphragm, the spacer, the base ring, the bipolar plate and the PCB housed inside the ECM. This error causes problems such as poor contact between internal enclosures, deformation due to pressure, and provides a cause of a very low yield.

In more detail, the conventional manufacturing method for manufacturing the ECM is laminated or press-fitted the inner housing such as the diaphragm, spacer, base ring, bipolar plate inside the cylindrical case is blocked one side and the end of the cylindrical case and PCB It is manufactured using the method of welding one side edge or side of the PCB. Alternatively, the PCB is also housed inside the cylindrical case and curled (Curling) the end of the cylindrical case to pressurize the PCB and the interior.

First of all, when welding or bonding the PCB and the case, when the inside of the enclosure is made smaller than the standard size, a small gap or gap is formed, thereby causing a poor contact between the objects received without a separate bonding process Causing a decrease in production yield. On the other hand, when fabricated larger than the standard size, it protrudes into the opening of the cylindrical case, making the PCB bonding process difficult, or even when bonding the PCB, bending of the PCB, deformation of the enclosure, thereby lowering the manufacturing yield. This has a similar adverse effect in the case of using the curing process, there is a problem that increases the defective rate and eventually raises the ECM manufacturing cost.

In addition, ECM is a normal operation is possible only if the gap between the diaphragm and the bipolar plate is fixed properly, can be expected excellent performance, desired performance. However, in the case of the conventional PCB, the above-described problems occur due to an error in the manufacturing process, and this problem is also applied to the diaphragm and the bipolar plate, causing problems such as bending of the diaphragm and increasing the separation distance between the diaphragm and the bipolar plate. Such bending, increase or decrease of the separation distance causes a problem of deterioration of the sensitivity of the ECM, malfunction, and soon leading to a decrease in manufacturing yield.

Accordingly, it is an object of the present invention to provide a condenser microphone capable of improving normal operation and manufacturing yield.

In addition, another object of the present invention is to clearly present the insertion position of the washer spring, and to distinguish the effects and actions according to the insertion position, to use the most efficient type of condenser microphone.

Another object of the present invention is to provide a method that does not cause an increase in the number of parts caused by the addition of a washer spring, thereby providing a manufacturing method and a structure of a condenser microphone which does not cause an increase in manufacturing cost due to the use of the washer spring. It is.

In addition, another object of the present invention is to consider the current manufacturing process, to reasonably limit the thickness of the washer spring provided, to limit the deformation range, so that it can be applied immediately to the current manufacturing method.

Finally, another object of the present invention is to clarify that the effect of using the washer spring is not bound to the case sealing method, to prove that the technical idea of the present invention is universally applicable.

In order to achieve the above object, at least one of the condenser microphone case according to the present invention, an inner accommodating body including a diaphragm, a spacer, a bipolar plate, and first and second base rings housed in the case, and at least one of the diaphragm or the bipolar plate. And a washer spring for providing an elastic force between the printed circuit board which receives an electrical signal from any one, and the inner housing, the inner housing, the case, and the printed circuit board.

The washer spring may be inserted between the case and the diaphragm.

In addition, the diaphragm may include a vibrating membrane and a polar ring for fixing and supporting the vibrating membrane and providing a conductive path to the vibrating membrane, and the washer spring may be integral with the polar ring.

The diaphragm is electrically connected to the printed circuit board via the washer spring and the case.

In addition, the washer spring may be inserted between the bipolar plate and the second base ring, the bipolar plate may be electrically connected to the printed circuit board by the washer spring and the second base ring.

The washer spring may be bellville type, dish type, cone type, wave type, spring pin type.

The washer spring has a thickness in the range of 0.2mm to 0.05mm, preferably it is determined within the range of 0.15mm to 0.1mm, the elastic force action direction deformation range of the washer spring is determined within 0.09mm to 0.01mm It is good to be.

The printed circuit board may be accommodated in the case, and the case may be sealed by a curling method, or may be sealed by welding or bonding with the printed circuit board.

Other features and effects of the present invention other than the above object will become apparent from the description of the embodiments with reference to the accompanying drawings. Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 8.

1 is a view showing the assembled back-type electret condenser microphone according to the first embodiment of the present invention, Figure 2 is a cross-sectional view showing an assembled cross-section of the back-type electret condenser microphone of FIG.

1 and 2, the ECM according to the present invention includes a case 1, a washer spring 2, a diaphragm 3, a spacer 5, a bipolar plate 6, a first base ring 8, The second base ring 9 and the printed circuit board 10 is provided.

The case 1 houses a washer spring 2, a diaphragm 3, a spacer 5, a bipolar plate 6, a first base ring 8, and a second base ring 9 therein. To protect the internal components from impact. In addition, the case 1 shields the shielding of acoustic noise and electromagnetic noise introduced from the outside, so that the electrical signal conversion of the sound can proceed smoothly. In addition, the case 1 electrically connects the diaphragm 3 and the printed circuit board 10. To this end, the case 1 is manufactured in a cylindrical shape, one side of which is blocked except for a sound hole (or a sound inflow hole 11) through which sound is introduced, and the other side is provided in an open form (opening). . In the case 1, a washer spring 2, a diaphragm 3, a spacer 5, a bipolar plate 6, and first and second base rings 8 and 9 are sequentially stacked on an inner surface where sound holes are formed. Become. In addition, the opening of the case 1 is coupled to and sealed by the side, side edges of the printed circuit board 10 by adhesion, welding, and the like. Alternatively, the printed circuit board 10 is accommodated in the case 1, and the end of the opening of the case 1 is cured and sealed. The case 1 is manufactured by using a conductive metal such as aluminum and copper for shielding noise, and may be used in the form of plating of gold or nickel for improving electrical conductivity and preventing corrosion.

The washer spring 2 prevents the flow of the spacer 5, the diaphragm 3, the bipolar plate 6, the first and second base rings 8, 9 due to the tolerances generated during the manufacture of the ECM, and the case (1) and the diaphragm 3 and the printed circuit board 10 is electrically connected. To this end, the washer spring 2 is inserted between the case 1 and the diaphragm 3. Through this, the washer spring 2 removes unnecessary space between the diaphragm 3, in particular, the polar ring 3a, the first base ring 8, and the case 1, which is generated due to tolerances during manufacture, and is pressed. Induce close contact between parts. In addition, the washer spring (2) allows the adjustment of the process pressure or the coupling pressure generated during the assembly or sealing of the parts laminated in a narrow space, so that the curing work of the case (1), the assembly work of the PCB (10) Part damage such as deformation of the diaphragm (3) occurring in the will be minimized. Detailed description thereof will be described later with reference to FIGS. 3 and 4.

Diaphragm (Diaphragm, 3) is vibrated by the sound pressure of the sound transmitted through the sound hole 11 of the case 1, generating a change in the electric field. In addition, the diaphragm 3 serves as an electrode for generating an electric field for converting an acoustic signal into an electrical signal. To this end, the diaphragm 3 has a diaphragm 3b and a polar ring 3a. The vibrating membrane 3b changes the electric field by vibration caused by sound pressure. To this end, the vibration membrane 3b is manufactured by sputtering nickel (Ni) or gold (Au) for conductive properties on a film such as polyethylene terephthalate (PET) having a thickness of several micrometers. The polar ring 3a is used to separate and maintain the gap between the vibrating membrane 3b and the inner surface of the case 1, and the vibrating membrane 3b is on one surface and the washer spring 2 is on the other surface. In addition, the polar ring 3a electrically connects the printed circuit board 10 and the vibrating membrane 3b via the case 1 and the washer spring 2. The polar ring 3a is manufactured in the form of a donut and a ring using a metal such as copper and an alloy thereof.

The spacer 5 is positioned between the diaphragm 3 and the bipolar plate 6 to serve to arrange the diaphragm 3 and the bipolar plate 6 in parallel at a predetermined distance. In addition, the spacer 5 allows the diaphragm 3 and the bipolar plate 6 to be electrically insulated, and is manufactured in the form of a donut or a ring using a material having good insulating properties such as an acrylic resin.

The double plate (or dielectric plate, BE, 6) forms an electrostatic field together with the diaphragm 3 to convert the sound pressure caused by the acoustic signal into an electrical signal. To this end, the bipolar plate 6 is composed of an electret polymer film 6a and a metal plate (or bipolar electrode 6b). The electret polymer film 6a is semi-permanently charged and forms an electrostatic field by this charged charge. To this end, the bipolar plate 6 is manufactured by injecting electric charge through a charge injector after pressurizing and heat-sealing a polymer film such as PTFE (Poly Tetra Fluoro Ethylene), PFA (Perfluoroalkoxy), or FEP (Fluoroethylenepropylene) to the conductive bipolar 6b. do. At this time, the electrode 6b uses a metal such as copper, bronze, brass, and phosphor bronze.

The first base ring (or insulating base ring 8) is positioned between the bipolar plate 6 and the case 1 to electrically insulate the bipolar plate 6 and the case 1. The first base ring 8 is made of a cylindrical column or a polygonal column with a space formed therein, the cylinder or column side is in contact with the case 1, and the second base ring 9 is accommodated in the inner space. In addition, any one of the bottom surface or the top surface of the first base ring 8 supports the spacer 5, and the other components therein by the case 1, the spacer 5, and the washer spring 2. It plays a role of fixing it firmly.

The second base ring (or conductive base ring) 9 serves to electrically connect the bipolar plate 6 and the printed circuit board 10. The outer diameter of the second base ring 9 is manufactured to a size corresponding to the inner diameter of the first base ring 8, so that the second base ring 9 does not vibrate due to external impact. In addition, the second base ring 9 is also made of a cylindrical or polygonal column in a ring shape, the bottom surface of which is in contact with the bipolar plate 6 and the top surface of the printed circuit board 10.

Printed Circuit Boards (hereinafter referred to as "PCBs") 10 are formed with circuits and terminals for amplifying and filtering an electric signal generated by a change in an electric field and transmitting them to the outside. To this end, the PCB 10 includes an amplifier such as a field effect transistor (hereinafter referred to as a "FET") to amplify the change in the electric field, and an MC having one or more capacitors to filter out noise. Multilayer Ceramic Capacitor (hereinafter referred to as "MLCC") has a filter circuit. On one side of the printed circuit board 10, an amplification element, a filter circuit and a circuit pattern for connecting them are formed, and on the other side, terminals for connecting to an external device or a substrate and a solder ball are formed. The PCB 10 is also electrically connected to the diaphragm 3 and the bipolar plate 6 by the second base ring 9 and the case 1. Here, in the case of using the FET as an amplifying element, the gate terminal of the FET is connected to the bipolar plate 6 by the second base ring 9, and the source terminal is connected to the diaphragm (by the case 1). It is connected to 3) and the drain terminal is connected to MLCC.

3 is a view showing the shape and action of the washer spring of Figures 1 and 2 showing the shape of the washer spring.

3 shows a C-washer spring 2 in its basic form. As shown in FIG. 3, the washer spring 2 is manufactured in a ring shape by shifting a metal plate having a predetermined thickness so as not to meet at both ends. In addition to the C-washer spring 2, a spring-pin type is also included. Here, in FIG. 3, only one end is bent by way of example, but it is also possible to use a washer spring 2 having both ends bent in different directions. In FIG. 3, the direction indicated by arrow A is a direction in which pressure applied from the outside acts, and the direction indicated by arrow B is a direction of force applied by washer spring 2 to the external pressure. That is, when the case 1 is located in the lower part of the washer spring ring 2 (down direction in FIG. 3), and the polar ring 3a and the spacer 5 are pressed in the upper part (upward direction in FIG. 3), A The washer spring 2 acts on the pressure. On the contrary, the washer spring 2 is compressed in the A direction and generates a repulsive force in the B direction. That is, only the size of the deformation height d2 is reduced without changing the outer diameter d3 or the thickness d1 of the washer spring 2. Accordingly, when the first base ring 8, the spacer 5, and the diaphragm 3 are accommodated in the case 1 and sealed, even if unnecessary space is generated due to the manufacturing process, the washer spring 2 is stored inside. In particular, the case 1, the spacer 5, and the diaphragm 3 come into close contact with each other. Moreover, even when the required space becomes narrow, the washer spring 2 contracts by elasticity, and a space in which the spacer 5, the first base ring 8, and the diaphragm 3 can be accommodated is formed. In this way, in order to obtain the buffering and pressing effect by the washer spring 2, the thickness of the polar ring 3a is slightly reduced, or the deformation height d2 of the washer spring 2 is within the error range of the case 1. It is enough to apply the method of lengthening a little longer.

Considering the manufacturing process that can be implemented at present, it is preferable that the thickness of the washer spring 2 is determined within the range of 0.5 mm to 0.05 mm. First, when the washer spring 2 is too thin, it is difficult to obtain a desired pressurization and buffering effect because the elasticity of the current material becomes small, and a manufacturing cost increases significantly in order to obtain a desired pressurization and buffering effect. In addition, the current production thickness of 4mm, 6mm, 8mm ECM thickness of the cylinder is about 1.5mm, 2.87mm, 3.5mm, copper alloy thinner, the material washer spring of the resin system (2) The thickness of must be determined within 0.5mm. Furthermore, considering that the tolerances generated during ECM manufacture are in the range of approximately 0.2 mm, the thickness of the washer springs 2 is preferably determined within the range of 0.15 mm to 0.1 mm. In addition, the range of the washer spring 2 deformation height at this time is preferably determined in the range of 0.08mm to 0.01mm in consideration of the tolerance.

4 is a view illustrating various examples of the washer spring of FIG. 3.

Referring to FIG. 4, FIG. 4A illustrates a ring washer spring 22 having a concave shape between an inner diameter and an outer diameter. That is, the figure which showed the example in the case where the shape of the cross section which cut washer spring is "V" shape. In addition, Figure 4b shows a wave washer (Wave Washer) (23) is a washer spring 23 formed in the shape of water by forming one or more bends. 4C is a view showing a Belleville Washer 24 having an extension extending obliquely at the outer diameter portion of the plate washer spring. In addition, FIG. 4D is a view illustrating the washer spring 25 having a shape in which the washer spring 25 itself is bent in a “V” shape unlike FIG. 4A. In addition, conical washer springs and toothed washer springs in which serrated wings are formed on the washer springs are also applicable to embodiments of the present invention.

5 is a cross-sectional view of the ECM according to the second embodiment of the present invention. Unlike the first embodiment, the washer spring 32 is inserted between the second base ring 39 and the bipolar plate 36. Except that, since the configuration and operation are the same as in the first embodiment, a detailed description of the same configuration and operation as the first embodiment in the second embodiment will be omitted.

The washer spring 32 in this second embodiment electrically connects the PCB 40 and the bipolar plate 36 via the second base ring 39. In addition, the washer spring 32 is inserted between the bipolar plate 36 and the second base ring 39, and serves to cushion or pressurize. Through this, the contact between the second base ring 39 and the printed circuit board 40 can be made more sure. In addition, by pressurizing or buffering the lower portion of the bipolar plate 36, the contact between the bipolar plate 36, the spacer 35, the diaphragm 33, and the case 31 may be more firm, or pressure applied thereto may be applied. Dispersion prevents damage of the bipolar plate 36, the spacer 35, the diaphragm 33, and the case 31.

FIG. 6 is a view showing a cross section of an ECM according to a third embodiment of the present invention, showing a foil type ECM having an electret in a diaphragm.

The foil type ECM according to the third embodiment of the present invention includes a case 51, a washer spring 52, an electret diaphragm 53, a spacer 55, a bipolar plate 56, a first base ring 58, A second base ring 59 and a printed circuit board 60 are provided.

In describing the third embodiment, detailed descriptions of operations and characteristics of the same configuration as those of the first embodiment or the second embodiment will be omitted.

The bipolar plate 56 forms an electrostatic field together with the electret diaphragm 53, converts a sound pressure into an electrical signal, and provides the electrostatic field to the PCB 60. The bipolar plate 56 is electrically connected to the PCB 60 by the washer spring 52 and the second base ring 59. In addition, the washer spring 52 inserted between the bipolar plate 56 and the second base ring 59 receives pressure in the direction of the diaphragm 53, thereby stably maintaining a constant distance from the diaphragm 53. It can be maintained.

The second base ring 59 electrically connects the PCB 60 and the bipolar plate 56 with the washer springs 52 interposed therebetween. In addition, the second base ring 59 supports the washer spring 52, the bipolar plate 56, and the electret diaphragm 53 together with the PCB 60, so that the enclosures inside the case 51 are more robust. Contact or fix it securely.

The electret vibrating plate 53 forms an electrostatic field together with the bipolar plate 56, and is divided into a polar ring 53a and an electret vibrating membrane 53b. As described above, the electret diaphragm 53 vibrates by sound pressure and converts an acoustic signal into an electrical signal. Unlike the bag type ECM, the electret diaphragm 53 also serves as an electret in which the diaphragm 53 forms an electrostatic field. That is, the vibration characteristics of the electret diaphragm 53 are slightly bad as the material of the vibrating membrane 53b, but they are produced using a polymer film which can charge and hold electric charges. The electret diaphragm 53 faces the bipolar plate 56 with the spacer 55 interposed therebetween. An electric charge is charged on the surface of the electret diaphragm 53 facing the bipolar plate 56 to form an electrostatic field for generating an electric signal.

7 is a view showing another example of a foil type ECM according to a fourth embodiment of the present invention.

The fourth embodiment is almost identical in structure, operation and operation to the third embodiment except that the insertion positions of the washer springs 63 are different. In addition, since the action by the washer spring 63 is almost similar to the first embodiment described above, a detailed description thereof will be omitted.

That is, the foil type ECM shown in FIG. 7 has a washer spring 62 inserted between the polar ring 63a of the diaphragm 63 and the case 61. Through this, together with the first and second bases 68, 69 and the case 61, the bipolar plate 66, the spacer 65, and the diaphragm 63 are more closely adhered to each other, and more than necessary to be applied to them. Protect the pressure by buffering it. In addition, it is in close contact with the washer spring 62, the diaphragm 63 and the bipolar plate 66 can maintain a constant interval even if an error occurs in the process.

On the other hand, it can be predicted through the first to fourth embodiments, the washer of the present invention can be applied simultaneously between the diaphragm and the case, between the second base ring and the bipolar plate. That is, two polar rings may be provided in one ECM. In this case, however, the thickness of the ECM is increased, and the manufacturing cost and the time required for the increase in the number of parts can be increased. In addition, although a method of inserting between the second or first base ring and the PCB can be considered, in this case, since there is a fear of causing local deformation and breakage of the PCB, the method described in the first to fourth embodiments will be described. The part may be the best fit.

8 is a view showing a fifth embodiment according to the present invention, in which the polar ring is replaced with a washer spring in the first and fourth embodiments.

Also in the description of the fifth embodiment, only operations and characteristics of configurations different from those of the first to fourth embodiments will be described, and detailed descriptions of the similar configurations and effects will be omitted.

Referring to FIG. 8, the ECM according to the fifth embodiment of the present invention includes a case 71, a washer spring 72, a diaphragm 73, a spacer 75, a bipolar plate 76, and a first base ring 78. ), A second base ring 79 and a PCB (80).

The washer spring 72 supports and fixes the vibration membrane 75, and electrically connects the vibration membrane 75 and the PCB 80. In addition, the washer spring 72 buffers and disperses pressure applied to the vibrating membrane 73, the spacer 75, and the bipolar plate 76 more than necessary, and thus the vibrating membrane 73, the spacer 75, and the bipolar plate. 76, the first base ring 78 and the second base ring 79 are prevented from being broken or deformed by excessive pressure. In addition, the washer spring 72 is to compensate for the insufficient pressure, so that the inner enclosures more tightly to perform a normal operation.

The vibrating membrane 72 generates vibration by sound pressure to generate an electrical signal, and provides the generated electrical signal to the PCB 80 via the washer spring 72 and the case 71. To this end, the vibration membrane 72 is made of a thin polymer film having good vibration characteristics. In the case of the foil-type ECM, the diaphragm 72 also serves as an electret.

The bipolar plate 76 is connected to the PCB 80 by the second base ring 79, and generates an electrical signal together with the vibrating membrane 72 to provide the PCB 80. In the case of the back type ECM, the bipolar plate 76 further includes an electret polymer film for generating an electrostatic field.

Since other configurations have been described through the first to fourth embodiments, detailed descriptions thereof will be omitted. In the fifth embodiment, the polar ring provided in the diaphragm is omitted and replaced with a washer spring. This has the advantage that the fifth embodiment can expect almost the same effect while reducing the number of parts than the first to fourth embodiments.

As described above, ECMs provided through the first to fifth embodiments of the present invention can reduce malfunctions, deterioration, and defects caused by inevitable tolerances occurring during manufacturing.

First, when the gap between components is more than necessary due to an error in the process, defective electrical contact or change in the gap between the diaphragm and the bipolar plate may occur. However, in the present invention, by contacting the gap that is more than necessary through the washer spring to prevent the occurrence of defective phosphate due to electrical contact failure, and to prevent the increase of the separation distance between the diaphragm and the bipolar plate, almost all ECM products It is possible to maintain almost the same sensitivity characteristics.

In addition, when the spacing between parts is made very dense, the washer spring is deformed by elasticity, thereby providing a spacing for the parts to be maintained, so that the occurrence of defective parts due to the failure of adjustment of the tolerance is significantly reduced.

In addition, since the manufacturing error can be sufficiently taken into consideration in consideration of the height of the washer spring, it is possible to reduce the trouble of precision machining and the like, which provides an effect that leads to a reduction in the manufacturing cost.

In addition, the drawings for explaining the first to fifth embodiments have shown an example of the case where the sealing of the internal containment is terminated by the Curling Cape. However, the first to fifth embodiments of the present invention are equally applicable to a welding type ECM for sealing an ECM by welding or bonding a printed circuit board to a case. The application example of the washer spring in the welding method is the same except for the method of bonding the case and the PCB, and a detailed description thereof will be omitted since it is well known to those skilled in the art.

As described above, the condenser microphone having a washer spring according to the present invention can be operated normally by the washer spring even if an error occurs in the manufacturing process, and can maintain an even quality, and reduce the defective rate to greatly improve the production yield. Makes it possible.

In addition, the condenser microphone having a washer spring according to the present invention is the easiest and most effective application of the washer spring, suggesting the effect and action accordingly, the efficient and rational selection of the condenser microphone and the application of the manufacturing method It becomes possible.

In addition, the condenser microphone having a washer spring according to the present invention provides a method and structure which can prevent an increase in the number of parts due to the adoption of the washer spring, thereby preventing the process cost due to the washer spring to be increased. Do.

In addition, the condenser microphone having a washer spring according to the present invention limits the thickness and the deformation range of the washer spring within the practically applicable range, and provides a range in which the effect is apparent, and is easily applied to the actual manufacturing process. It becomes possible.

Finally, the condenser microphone having a washer spring according to the present invention shows that the application of the washer spring can be applied universally without regard to additional matters such as sealing type, and also in the condenser microphone of various types. To provide.

Claims (12)

A case; An inner enclosure including a diaphragm, a spacer, a bipolar plate, and first and second base rings housed in the case; A printed circuit board receiving an electrical signal from at least one of the diaphragm and the bipolar plate; And a washer spring for providing an elastic force between the inner enclosures, the inner enclosure, the case, and the printed circuit board. The method of claim 1, The washer spring is electret microphone having a washer spring, characterized in that inserted between the case and the diaphragm. The method of claim 1, The diaphragm is A vibrating membrane; And a polar ring for fixing and supporting the vibrating membrane and providing a conductive path to the vibrating membrane. The method of claim 3, wherein And said washer spring is integral with said polar ring. The method according to claim 2 or 4, And said diaphragm is electrically connected to a printed circuit board via said washer spring and said case. The method of claim 1, The washer spring is An electret microphone having a washer spring, which is inserted between the bipolar plate and the second base ring. The method of claim 6, And the bipolar plate is electrically connected to the printed circuit board by the washer spring and the second base ring. The method of claim 1, The washer spring is An electret microphone having a washer spring, characterized by a bellville, dish, cone, wave, and spring pin. The method of claim 1, The washer spring is thick An electret microphone having a washer spring having a range of 0.2 mm to 0.05 mm, and preferably determined within a range of 0.15 mm to 0.1 mm. The method of claim 1, The range of deformation of the elastic force acting direction of the washer spring is 0.09mm to 0.01mm electret microphone having a washer spring. The method of claim 1, The printed circuit board is accommodated in the case, Electret microphone having a washer spring, characterized in that the case is curled. The method of claim 1, The case is an electret microphone having a washer spring, characterized in that the sealing is welded or bonded to the printed circuit board.

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