Electret microphone capsule

Abstract

The utility model discloses an electret microphone head, comprising a shell, a dustproof net, a diaphragm, a gasket, a back plate, a circuit board, a cavity and a conductive glue; by arranging the back plate and the circuit board in the installation cavity, coordinating the cavity in the installation cavity and being located between the back plate and the circuit board, arranging the conductive glue in a third through hole and fitting with the inner wall surface of the third through hole, the top surface of the conductive glue abuts against the back plate, and the bottom surface of the conductive glue abuts against the circuit board, the electret microphone head has fewer parts, and the production and assembly steps are reduced, which brings convenience to production; the conductive glue and the back plate and the circuit board are in surface contact structure, which effectively increases the contact area and forms a sealed structure, does not produce gap permeability, and can effectively isolate the contact surface of the conductive glue and the back plate and the circuit board from the air, thereby protecting the metal parts on the back plate and the circuit board from oxidation, improving the quality of the product, reducing the on-resistance, and meeting the existing needs.

Description

Technical Field

[0001] The utility model relates to the field of electret microphone technology, in particular to an electret microphone sound head. Background Art

[0002] With the continuous development of social economy and the continuous improvement of science and technology, more and more products are being manufactured and innovated. Microphone, scientifically known as microphone, is translated from the English word microphone (transmitter), also known as microphone, micro-phone. Microphone is an energy conversion device that converts sound signals into electrical signals. Microphones can be divided into dynamic microphones, condenser microphones, electret microphones and silicon micro-microphones. In addition, there are liquid microphones and laser microphones.

[0003] The electret microphone includes an acoustic-electric conversion part and an impedance conversion part; the core part of the electret microphone is the sound head, also known as an acoustic-electric transducer or a microphone core. The key components of the sound head are the electret and the vibration membrane (abbreviated as the vibration membrane). The electret is a polymer film material that can store electric charge, which is attached to a metal plate to form a back plate. After the polymer film material surface of the back plate that can store electric charge is electreted by a high-voltage electric field, the polymer film material stores electric charge. The vibration membrane is an extremely thin polymer material film bonded to a metal ring, and a layer of pure gold or other metal material layer is evaporated on one side. The evaporated gold surface or other metal material of the diaphragm faces outward and is connected to the shell. The other side of the diaphragm is separated from the back plate by a gasket. In this way, a small parallel gap is formed between the diaphragm and the back plate, thus forming a flat plate capacitor. The back plate and the diaphragm at both ends of the gasket have opposite charges, forming a potential difference. When the diaphragm vibrates due to sound waves, the diaphragm surface is displaced, causing a change in capacitance. The electric field at both ends also changes, thereby generating an alternating voltage that changes with the sound waves.

[0004] The current electret microphone sound head generally includes a shell, a cavity, a small spring, a large spring, a metal electrode, a back plate and a circuit board. The small spring, the metal electrode and the large spring are connected and arranged between the back plate and the circuit board in sequence, so that the back plate and the circuit board are electrically conductive. However, this type of electret microphone sound head has many parts, many production and assembly steps, and complicated operations, which brings inconvenience to production; and the small spring and the large spring are usually wound with stainless steel wire materials, and their on-resistance is relatively large, and the thermal noise is high under working conditions; the small spring is in circular linear contact with the back plate and the metal electrode, and the connection between the large spring and the metal electrode and the circuit board is in circular linear contact, with a small contact area, and more space is left around the small spring and the large spring, which cannot form an effectively sealed structure, and it is easy to produce gaps for ventilation. The metal parts on the back plate and the circuit board are easily oxidized, which affects the quality of the product. The service life of the product is short and cannot meet the existing needs. Therefore, it is necessary to study a new technical solution to improve the above problems. Utility Model Content

[0005] In view of the above, the utility model aims to improve the defects of the prior art, and its main purpose is to provide an electret microphone capsule, which can effectively solve the problems of the current electret microphone capsule having more parts, more production and assembly steps, complicated operation, larger on-resistance, higher thermal noise under working condition, smaller contact area of ​​the circular linear contact mode, more space left around the small spring and the large spring, which cannot form an effective sealing structure, easily causing gap ventilation, and the metal parts on the back plate and the circuit board are easily oxidized, thus affecting product quality.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A kind of electret microphone sound head includes a shell, a dustproof net, a diaphragm, a gasket, a back plate, a circuit board, a cavity and a conductive glue; the shell has a mounting cavity and a plurality of first through holes, the plurality of first through holes are connected to the mounting cavity, and the plurality of first through holes are arranged at the upper end of the shell; the dustproof net is arranged in the mounting cavity and covers the plurality of first through holes; the diaphragm is arranged in the mounting cavity and overlapped on the lower surface of the dustproof net; the gasket is arranged in the mounting cavity and overlapped on the lower surface of the diaphragm; the back plate is arranged in the mounting cavity and is located below the gasket, and the back plate has a plurality of second through holes; the circuit board is arranged at the lower end of the mounting cavity; the cavity is arranged in the mounting cavity and is located between the back plate and the circuit board, and a third through hole is arranged on the cavity, and the third through hole is arranged between the back plate and the circuit board; the conductive glue is arranged in the third through hole and fits with the inner wall surface of the third through hole, the top surface of the conductive glue abuts against the back plate, and the bottom surface of the conductive glue abuts against the circuit board.

[0008] As a preferred solution, the dustproof net is a steel net. Since a plurality of first through holes are provided on the outer shell, dust and other objects may enter the interior of the electret microphone head through the first through holes, thereby affecting the sensitivity and accuracy of the electret microphone head. Therefore, providing a dustproof net can effectively reduce the phenomenon of tiny objects such as dust entering the interior of the electret microphone head. The dustproof net is a steel net, which is more durable and prolongs the service life of the product.

[0009] As a preferred solution, the third through hole is arranged in the middle of the cavity.

[0010] As a preferred solution, the third through hole is circular, and correspondingly, the conductive adhesive is a cylindrical structure.

[0011] As a preferred solution, the conductive adhesive is made of a composite of silica gel and silver microparticles or silica gel and copper microparticles, and has the excellent conductivity of silver or copper metal materials, small conduction resistance, and good elasticity.

[0012] As a preferred solution, a first groove is provided on the upper surface of the cavity, a second groove is provided on the lower surface of the cavity, a fourth through hole is provided between the second groove and the first groove, and the fourth through hole is connected to both the first groove and the second groove.

[0013] As a preferred solution, the first groove and the second groove are both annular structures.

[0014] As a preferred solution, a first damping plate and a second damping plate are further provided. The first damping plate and the second damping plate are overlapped and located in the first groove. The first damping plate and the second damping plate are both located below the back pole plate. The first damping plate and the second damping plate can modulate and attenuate the sound transmission amplitude of each frequency band to achieve better sound pickup effect and improve product quality.

[0015] As a preferred solution, a signal output terminal is provided on the outer surface of the circuit board.

[0016] Compared with the prior art, the utility model has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solution that:

[0017] By setting the back plate in the installation cavity and being located below the gasket, the back plate has a plurality of second through holes, the circuit board is set at the lower end of the installation cavity, and the cavity is set in the installation cavity and is located between the back plate and the circuit board, the cavity is provided with a third through hole, and the third through hole is set between the back plate and the circuit board, the conductive glue is set in the third through hole and fits with the inner wall surface of the third through hole, the top surface of the conductive glue abuts against the back plate, and the bottom surface of the conductive glue abuts against the circuit board. The electret microphone head has fewer parts, fewer production and assembly steps, and is simple to operate, which brings convenience to production; and the conductive glue is in a surface contact structure with the back plate and the circuit board, which effectively increases the contact area and can effectively form a sealed structure without generating gaps for ventilation, and can effectively isolate the contact surface of the conductive glue with the back plate and the circuit board from the air, thereby protecting the metal parts on the back plate and the circuit board from oxidation, greatly improving the quality of the product, extending the service life of the product, effectively reducing the on-resistance, reducing the thermal noise under working conditions, making the use of the product more stable and reliable, and meeting existing needs.

[0018] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a preferred embodiment of the utility model.

[0020] Description of the accompanying drawings:

[0021] 10. Shell 11. Installation cavity

[0022] 12. First through hole 20, dust screen

[0023] 30, diaphragm 40, gasket

[0024] 50. back plate 51. second through hole

[0025] 60. Circuit board 70. Cavity

[0026] 71. third through hole 72. first groove

[0027] 73, second groove 74, fourth through hole

[0028] 80. Conductive adhesive 90. First damping sheet

[0029] 100. Second damping plate. DETAILED DESCRIPTION

[0030] Please refer to Figure 1As shown, it shows the specific structure of the preferred embodiment of the utility model, including a housing 10, a dustproof net 20, a diaphragm 30, a gasket 40, a back plate 50, a circuit board 60, a cavity 70 and a conductive adhesive 80.

[0031] The shell 10 has an installation cavity 11 and a plurality of first through holes 12, the plurality of first through holes 12 are connected to the installation cavity 11, and the plurality of first through holes 12 are arranged at the upper end of the shell 10; the dustproof net 20 is arranged in the installation cavity 11 and covers the plurality of first through holes 12; in the present embodiment, the dustproof net 20 is a steel net. Since a plurality of first through holes 12 are arranged on the shell 10, there is a situation where dust and other objects may enter the interior of the electret microphone head through the first through holes 12, thereby affecting the sensitivity and accuracy of the electret microphone head. Therefore, the provision of the dustproof net 20 can effectively reduce the phenomenon of dust and other tiny objects entering the interior of the electret microphone head. The dustproof net 20 is a steel net, which is more durable and prolongs the service life of the product.

[0032] The diaphragm 30 is arranged in the installation cavity 11 and overlapped on the lower surface of the dustproof net 20; the gasket 40 is arranged in the installation cavity 11 and overlapped on the lower surface of the diaphragm 30; the back plate 50 is arranged in the installation cavity 11 and is located below the gasket 40, and the back plate 50 has a plurality of second through holes 51.

[0033] The circuit board 60 is disposed at the lower end of the mounting cavity 11 . In this embodiment, a signal output terminal (not shown) is disposed on the outer surface of the circuit board 60 , and the signal output terminal is used to connect to an external circuit.

[0034] The cavity 70 is arranged in the installation cavity 11 and is located between the back plate 50 and the circuit board 60. The cavity 70 is provided with a third through hole 71, and the third through hole 71 is arranged between the back plate 50 and the circuit board 60. In the present embodiment, the third through hole 71 is arranged in the middle of the cavity 70. The third through hole 71 is circular. The upper surface of the cavity 70 is provided with a first groove 72, and the lower surface of the cavity 70 is provided with a second groove 73. A fourth through hole 74 is provided between the second groove 73 and the first groove 72, and the fourth through hole 74 is provided between the first groove 72 and the The second grooves 73 are all connected; the fourth through hole 74 is one or more; specifically, the first groove 72 and the second groove 73 are both annular structures; further provided are a first damping plate 90 and a second damping plate 100, the first damping plate 90 and the second damping plate 100 are overlapped and located in the first groove 72, the first damping plate 90 and the second damping plate 100 are both located below the back plate 50, the first damping plate 90 and the second damping plate 100 can modulate and attenuate the sound transmission amplitude of each frequency band to achieve a better sound pickup effect and improve the quality of the product.

[0035] The conductive adhesive 80 is arranged in the third through hole 71 and fits with the inner wall surface of the third through hole 71, the top surface of the conductive adhesive 80 abuts against the back plate 50, and the bottom surface of the conductive adhesive 80 abuts against the circuit board 60; in the present embodiment, the conductive adhesive 80 is a cylindrical structure; the conductive adhesive 80 is made of a composite processing of silica gel and silver microparticles or silica gel and copper microparticles, and has excellent conductivity of silver or copper metal materials, small on-resistance, and good elasticity.

[0036] The production process of this embodiment is described in detail as follows:

[0037] First, prepare the housing 10, the dust net 20, the diaphragm 30, the gasket 40, the back plate 50, the circuit board 60, the cavity 70, the conductive glue 80, the first damping plate 90 and the second damping plate 100; then, overlap the first damping plate 90 and the second damping plate 100 and install them into the first groove 72 of the cavity 70, and then install the back plate 50 into the cavity 70 to form a semi-finished product; then, install the dust net 20, the diaphragm 30 and the gasket 40 into the housing in sequence. 10; then, the semi-finished product is loaded into the outer shell 10, and the back plate 50 is arranged between the gasket 40 and the cavity 70; then, the conductive glue 80 is loaded into the third through hole 71 of the cavity 70; finally, the circuit board 60 is loaded into the outer shell 10, so that the top surface of the conductive glue 80 abuts against the back plate 50 so as to be electrically conductive, and the bottom surface of the conductive glue 80 abuts against the circuit board 60 so as to be electrically conductive. The operation is simple, the assembly is convenient and quick, and it brings convenience to production.

[0038] The design focus of this utility model is:

[0039] By setting the back plate in the installation cavity and being located below the gasket, the back plate has a plurality of second through holes, the circuit board is set at the lower end of the installation cavity, and the cavity is set in the installation cavity and is located between the back plate and the circuit board, the cavity is provided with a third through hole, and the third through hole is set between the back plate and the circuit board, the conductive glue is set in the third through hole and fits with the inner wall surface of the third through hole, the top surface of the conductive glue abuts against the back plate, and the bottom surface of the conductive glue abuts against the circuit board. The electret microphone head has fewer parts, fewer production and assembly steps, and is simple to operate, which brings convenience to production; and the conductive glue is in a surface contact structure with the back plate and the circuit board, which effectively increases the contact area and can effectively form a sealed structure without generating gaps for ventilation, and can effectively isolate the contact surface of the conductive glue with the back plate and the circuit board from the air, thereby protecting the metal parts on the back plate and the circuit board from oxidation, greatly improving the quality of the product, extending the service life of the product, effectively reducing the on-resistance, reducing the thermal noise under working conditions, making the use of the product more stable and reliable, and meeting existing needs.

[0040] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An electret microphone capsule, characterized in that: It includes an outer shell, a dustproof net, a diaphragm, a gasket, a back plate, a circuit board, a cavity and a conductive adhesive; the outer shell has an installation cavity and a plurality of first through holes, the plurality of first through holes are connected to the installation cavity, and the plurality of first through holes are arranged at the upper end of the outer shell; the dustproof net is arranged in the installation cavity and covers the plurality of first through holes; the diaphragm is arranged in the installation cavity and overlapped on the lower surface of the dustproof net; the gasket is arranged in the installation cavity and overlapped on the lower surface of the diaphragm; the back plate is arranged in the installation cavity and is located below the gasket, and the back plate has a plurality of second through holes; the circuit board is arranged at the lower end of the installation cavity; the cavity is arranged in the installation cavity and is located between the back plate and the circuit board, a third through hole is arranged on the cavity, and the third through hole is arranged between the back plate and the circuit board; the conductive adhesive is arranged in the third through hole and fits with the inner wall surface of the third through hole, the top surface of the conductive adhesive abuts against the back plate, and the bottom surface of the conductive adhesive abuts against the circuit board.

2. The electret microphone capsule according to claim 1, characterized in that: The dustproof net is a steel net.

3. The electret microphone capsule according to claim 1, characterized in that: The third through hole is arranged in the middle of the cavity.

4. The electret microphone capsule according to claim 1, characterized in that: The third through hole is circular, and correspondingly, the conductive adhesive is a cylindrical structure.

5. The electret microphone capsule according to claim 1, characterized in that: The conductive adhesive is made by composite processing of silica gel and silver microparticles or silica gel and copper microparticles.

6. The electret microphone capsule according to claim 1, characterized in that: The upper surface of the cavity is provided with a first groove, the lower surface of the cavity is provided with a second groove, a fourth through hole is provided between the second groove and the first groove, and the fourth through hole is connected with both the first groove and the second groove.

7. The electret microphone capsule according to claim 6, characterized in that: The first groove and the second groove are both annular structures.

8. The electret microphone capsule according to claim 6, characterized in that: A first damping plate and a second damping plate are further provided. The first damping plate and the second damping plate are overlapped and located in the first groove. The first damping plate and the second damping plate are both located below the back plate.

9. The electret microphone capsule according to claim 1, characterized in that: The outer surface of the circuit board is provided with a signal output terminal.

Images