CN219536309U - Electret microphone - Google Patents

Abstract

The utility model discloses an electret microphone, and belongs to the technical field of microphones. The electret microphone comprises a shell, and a vibrating diaphragm group, an insulating gasket, a back electrode plate and a circuit board which are sequentially arranged and packaged in the shell, wherein the back electrode plate is electrically connected with the circuit board, the vibrating diaphragm group comprises a diaphragm and a metal ring, the diaphragm is arranged on the metal ring, the frequency range of the diaphragm is 2.5KHZ-3KHZ, and the thickness of the insulating gasket is in direct proportion to the outer diameter of the shell. The electret microphone can be used for clearly picking up high-frequency band sound, so that the recorded sound has better definition and saturation.

Description

Electret microphone

Technical Field

The utility model relates to the technical field of microphones, in particular to an electret microphone.

Background

The electret microphone is widely applied to the aspects of language pickup, sound signal detection and the like due to the characteristics of simple structure, small volume and high sensitivity. Among them, the electret microphone specifically refers to a condenser microphone in which a polarized power source is replaced with an electret that has been polarized by injecting electric charges in advance.

However, the frequency width of the electret microphone is limited due to the processing technology and the like, and the sensitivity to the high frequency band in the sound is insufficient, namely, the pickup of the high frequency band sound is not clear enough, so that the problem of turbidity and unclear of the sound picked up by the electret microphone is caused, and the definition and saturation of the sound are poor.

In view of the above, there is a need for an electret microphone to solve the above problems.

Disclosure of Invention

The utility model aims to provide an electret microphone which can be used for clearly picking up high-frequency band sound and enabling the recorded sound to be good in definition and saturation.

To achieve the purpose, the utility model adopts the following technical scheme:

electret microphone, including the shell and place in proper order and encapsulate to vibrating diaphragm group, insulating gasket, back polar plate and the circuit board inside the shell, the back polar plate with the circuit board electricity is connected, vibrating diaphragm group includes diaphragm and metal ring, the diaphragm sets up on the metal ring, the frequency range of diaphragm is 2.5KHZ-3KHZ, just insulating gasket's thickness with the external diameter of shell is directly proportional.

Further, the membrane is made by magnetron sputtering vacuum gold plating.

Further, the electret microphone further comprises a steel mesh arranged inside the shell and below the metal ring.

Further, the electret microphone further comprises a conducting piece, wherein the conducting piece is located between the back electrode plate and the circuit board and used for conducting the back electrode plate and the circuit board.

Further, the conducting member includes:

the copper sheet is connected between the first spring and the second spring, one end of the first spring is connected with the back electrode plate, and one end of the second spring is connected with the circuit board.

Further, the electret microphone further includes:

the plastic cavity is positioned above the back electrode plate, an inner cavity can be formed between the plastic cavity and the plastic ring, and the copper sheet is arranged on the top end face of the plastic cavity.

Further, the electret microphone further includes:

the head of the bolt is abutted to one end, which is not connected with the back electrode plate, of the first spring, and the end of the bolt sequentially penetrates through the plastic cavity and the copper sheet, so that the nut is screwed to the end of the bolt.

Further, the copper sheet is provided with an annular placing groove, the second spring is limited in the annular placing groove, and the second spring is covered on the periphery of the nut.

Further, damping cotton and damping cloth are stacked in the plastic cavity, the damping cotton is located above the back electrode plate, mounting holes are formed in the centers of the damping cotton and the damping cloth, and the first springs are limited in the mounting holes.

Further, the back electrode plates are provided with a plurality of sound transmission holes.

The beneficial effects of the utility model are as follows:

the insulating gasket is arranged between the vibrating diaphragm group and the back electrode plate, and the insulating gasket has the isolation function, so that the diaphragms in the vibrating diaphragm group and the back electrode plate can form a capacitor, and when the diaphragms are vibrated due to the sound wave function, the distance between the diaphragms and the back electrode plate can be changed slightly, and the change can cause the change of the capacitor between the diaphragms and the back electrode plate, so that the sound signal is converted into an electric signal; the back electrode plate is electrically connected with the circuit board, so that the electric signal can be preamplified through the circuit board, and the sound is picked up; meanwhile, as the frequency range of the diaphragm influences the frequency width of the electret microphone, the wider the frequency width is, the clearer and brighter the sound is in a certain range, so that the frequency range of the diaphragm is set to be 2.5KHZ-3KHZ, and the frequency width of the electret microphone can be enlarged; in addition, as the thickness of the insulating gasket affects the frequency characteristic and tone, in a certain range, the thicker the thickness of the insulating gasket is, the clearer the sound is, therefore, the thickness of the insulating gasket is in direct proportion to the outer diameter of the shell, namely, the larger the outer diameter of the shell is, the thicker the thickness of the insulating gasket adopted by the insulating gasket is, so that the frequency width of the electret microphone can be further enlarged, the pickup of the electret microphone to the high frequency band in the sound is clearer, the problem of turbidity and unclear after the picked sound can not occur, and the definition and saturation of the sound are better.

Drawings

FIG. 1 is an exploded schematic view of an electret microphone provided by the present utility model;

FIG. 2 is a schematic diagram of an assembly structure among a plastic cavity, a copper sheet and a second spring provided by the utility model;

fig. 3 is a graph comparing the frequency response curves of the electret microphone in the present embodiment with the prior art provided by the present utility model.

Reference numerals illustrate:

1-a housing; 2-steel mesh; 3-vibrating diaphragm group; 4-insulating spacers; 5-a back electrode plate; 51-sound-transmitting holes; 6-damping cotton; 7-damping cloth; 8-a bolt; 9-plastic cavity; 10-copper sheets; 101-an annular placement groove; 11-a nut; 12-a first spring; 13-a second spring; 14-plastic ring; 15-a circuit board; 16-mounting holes.

Detailed Description

All of the features disclosed in this specification, or all of the steps in a method or process disclosed, may be combined in any combination, except for mutually exclusive features and/or steps.

Any feature disclosed in this specification may be replaced by alternative features serving the same or equivalent purpose, unless expressly stated otherwise. That is, each feature is one example only of a generic series of equivalent or similar features, unless expressly stated otherwise. Like reference numerals refer to like elements throughout the specification.

In order to make the technical problems solved, the technical scheme adopted and the technical effects achieved by the utility model more clear, the technical scheme of the utility model is further described below by a specific embodiment in combination with the attached drawings.

According to the electret microphone, the pickup of high-frequency band sounds can be clear, more voice details are reserved, the clarity and saturation of the recorded sounds are good, namely, the sounds picked up through the electret microphone are clear and bright, the problem of unclear turbidity cannot occur, and therefore the electret microphone can be applied to sound equipment such as microphones and the like, and the electret microphone has good practicability.

Specifically, as shown in fig. 1 and 2, the electret microphone includes a housing 1, and a diaphragm group 3, an insulating spacer 4, a back-electrode plate 5, and a circuit board 15 which are placed and packaged in this order inside the housing 1; wherein, the back electrode plate 5 is electrically connected with the circuit board 15, and a plurality of sound transmission holes 51 are arranged on the back electrode plate 5, so that sound can uniformly transmit through the back electrode plate 5; the diaphragm group 3 comprises a diaphragm and a metal ring, the diaphragm is arranged on the metal ring, the frequency range of the diaphragm is 2.5KHZ-3KHZ, and the thickness of the insulating spacer 4 is in direct proportion to the outer diameter of the shell 1. Wherein, the shell 1 is an integrally formed alloy shell, and the shell 1 can be an aluminum alloy shell or a copper alloy shell.

By arranging the insulating gasket 4 between the diaphragm group 3 and the back electrode plate 5, the diaphragms in the diaphragm group 3 and the back electrode plate 5 can form a capacitor due to the isolation effect of the insulating gasket 4, when the diaphragms vibrate due to the sound wave effect, the distance between the diaphragms and the back electrode plate 5 also slightly changes, and the change in capacitance between the diaphragms and the back electrode plate 5 is caused, so that the sound signal is converted into an electric signal; the back plate 5 is then electrically connected to the circuit board 15 so that the electrical signal can be pre-amplified by the circuit board 15, thereby completing the pickup of sound. In this embodiment, the recording of the sound by the electret microphone is a common recording process in the prior art, so detailed description of the specific recording working principle of the electret microphone is not repeated here.

Meanwhile, as the frequency range of the diaphragm influences the frequency width of the electret microphone, the wider the frequency width is, the clearer and brighter the sound is in a certain range, so that the frequency range of the diaphragm is set to be 2.5KHZ-3KHZ, and the frequency width of the electret microphone can be enlarged; in addition, since the thickness of the insulating spacer 4 affects the frequency characteristic and tone, in a certain range, the thicker the thickness of the insulating spacer 4 is, the clearer the sound is, therefore, the thickness of the insulating spacer 4 is in direct proportion to the outer diameter of the housing 1, that is, the larger the outer diameter of the housing 1 is, the thicker the thickness of the insulating spacer 4 adopted is, so that the frequency width of the electret microphone can be further enlarged, the pick-up of the electret microphone to the high frequency band in the sound can be clearer, the problem of turbidity and unclear after the sound is picked up can be avoided, and the definition and saturation of the sound are better. In this embodiment, the membrane is made of polyphenylene sulfide (PPS), which has the characteristics of high mechanical strength, high temperature resistance, flame retardance, good thermal stability, and good electrical properties.

It should be noted that, the larger the outer diameter of the housing 1, the thicker the thickness of the insulating pad 4, and the clearer the sound, which means that, because the larger the outer diameter of the housing 1, the larger the membrane surface of the membrane in the diaphragm group 3 is, that is, the larger the amplitude of the center point of the membrane is, at this time, the distance between the membrane of the diaphragm group 3 and the back plate 5 (the thickness of the insulating pad 4) must be larger than the amplitude to ensure the effectiveness of the acoustic-electric conversion (if the amplitude is larger than the thickness of the insulating pad 4, serious distortion occurs in the electrical signal, and the sound is affected); at the same time, the thickness of the insulating spacer 4 also has an influence on the sound brightness of the electret microphone, so that the larger the outer diameter of the housing 1 is, the thicker the thickness of the insulating spacer 4 is, and the clearer the sound is.

As shown in fig. 3, curve a is a frequency response curve of the electret microphone in the prior art, curve B is a frequency response curve of the electret microphone in the present embodiment, and it can be obviously obtained from fig. 3 that the electret microphone in the present embodiment has better sensitivity to the high frequency band in the sound, that is, the electret microphone in the present embodiment can make the pickup of the electret microphone to the high frequency band in the sound clearer, so that the clarity and saturation of the sound are better. The frequency response curve specifically refers to a curve recorded at the output end of the signal generator, wherein the curve generates different frequency response values along with the frequency change of the input signal.

Specifically, for example, in an electret microphone with an outer diameter of 25mm of the casing 1, the thickness of the insulating spacer 4 may be between 0.06mm and 0.08mm, preferably 0.075mm, to enable better and clearer sound pickup.

Further, as the preparation mode of the diaphragm influences the frequency width and tone of sound, the diaphragm is made of magnetron sputtering vacuum gold plating, and the diaphragm made of the magnetron sputtering vacuum gold plating is better in metal coating force, and the coating is more uniform and thinner, so that the tensile capacity of the diaphragm is stronger under the condition that the coating does not crack, and further the regulation of the frequency width and tone of sound can be facilitated.

Particularly, in the surrounding environment, the radio frequency dry reactance of the mobile phone and the electromagnetic dry reactance generated when various electric products work can influence the input of high-frequency signals; therefore, as shown in fig. 1, the electret microphone further comprises a steel mesh 2, wherein the steel mesh 2 is arranged in the casing 1 and below the metal ring, namely, the steel mesh 2 is arranged on the bottom end surface of the casing 1, and the steel mesh 2 is used for shielding electromagnetic interference in the surrounding environment so as to avoid the occurrence of a squeak sound caused by sound recorded by the electret microphone.

Further, the electret microphone further comprises a conducting member arranged between the back-plate 5 and the circuit board 15 for conducting the back-plate 5 and the circuit board 15 so that an electrical connection is formed between the back-plate 5 and the circuit board 15.

Specifically, as shown in fig. 1 and 2, the conductive member includes a first spring 12, a copper sheet 10, and a second spring 13; wherein, the copper sheet 10 is connected between the first spring 12 and the second spring 13, and one end of the first spring 12 is connected with the back plate 5, and one end of the second spring 13 is connected with the circuit board 15, so that the back plate 5 can be electrically connected to the circuit board 15 through the first spring 12, the copper sheet 10 and the second spring 13 in sequence.

Specifically, as shown in fig. 1, the electret microphone further includes a plastic cavity 9 and a plastic ring 14, the plastic cavity 9 is located above the back plate 5, the copper sheet 10 is disposed on the top end surface of the plastic cavity 9, the plastic ring 14 is located above the plastic cavity 9, and the circuit board 15 is disposed on the plastic ring 14, so that the plastic cavity 9 can provide supporting effects for the copper sheet 10, the second spring 13, the plastic ring 14 and the circuit board 15; and mould chamber 9 and mould the ring 14 and be insulating material, and mould chamber 9 and mould the ring 14 each other and can form the inner chamber, can produce resonance with the resonance point of inner chamber after the sound enters into the inner chamber to amplify the resonance point frequency sound wave, in order to can adjust the resonance frequency point of sound chamber, thereby adjust the frequency response curve of sound.

Further, as shown in fig. 1 and 2, the electret microphone further comprises a bolt 8 and a nut 11, wherein the head of the bolt 8 is abutted to one end of the first spring 12 which is not connected with the back plate 5, and the end of the bolt 8 sequentially passes through the plastic cavity 9 and the copper sheet 10 so that the nut 11 is screwed to the end of the bolt 8, thereby fixing the plastic cavity 9 and the copper sheet 10; because the bolt 8 is not easy to deform and break, the fixing mode of the bolt 8 and the nut 11 is adopted to ensure that the fixing is stable, so that the plastic cavity 9 and the copper sheet 10 can be stably fixed.

Specifically, as shown in fig. 1 and 2, the copper sheet 10 has an annular placement groove 101, and the second spring 13 is limited in the annular placement groove 101, so that displacement of the second spring 13 can be avoided; the second spring 13 is provided around the outer periphery of the nut 11 so that the second spring 13 does not interfere with the end portions of the nut 11 and the bolt 8.

Further, as shown in fig. 1, damping cotton 6 and damping cloth 7 are stacked in the plastic cavity 9, the damping cotton 6 is located above the back plate 5, mounting holes 16 are formed in the centers of the damping cotton 6 and the damping cloth 7, and the first springs 12 are limited in the mounting holes 16 to avoid displacement of the first springs 12.

That is, at this time, the first spring 12 is vertically located in the mounting hole 16, and both ends of the first spring 12 are respectively abutted to the back plate 5 and the head of the bolt 8; meanwhile, the bolts 8 are connected through the copper sheets 10, and both ends of the second springs 13 are respectively abutted to the copper sheets 10 and the circuit board 15, so that the back plate 5 can be electrically connected to the circuit board 15 through the first springs 12, the bolts 8 and nuts 11, the copper sheets 10 and the second springs 13 in sequence.

By arranging the damping cotton 6, the damping cotton 6 can absorb or reduce stray sound, so that the damping cotton 6 can play a role in reducing the bottom noise in the sound; meanwhile, by arranging the damping cloth 7, the sound transmitted from the front to the rear can be blocked, so that the damping cloth 7 has the function of acoustic resistance.

Specifically, the circuit board 15 includes FR-4 four-layer board, the shielding of four-layer board is good, in order to be able to shield static electricity and wireless interference in the surrounding environment better; the circuit board 15 is manufactured by a gold plating process, so that the signal damage of the circuit board 15 is small, and the corrosion resistance is good. Wherein FR-4 specifically refers to a code of a flame-retardant material grade, which is a material specification that resin materials must be able to self-extinguish after passing through a burning state. The circuit board 15 in this embodiment is a circuit structure commonly found in the existing electret microphone, and therefore, detailed description of the specific structure and working principle of the circuit board 15 is omitted here.

The foregoing is merely exemplary of the present utility model, and those skilled in the art should not be considered as limiting the utility model, since modifications may be made in the specific embodiments and application scope of the utility model in light of the teachings of the present utility model.

Claims (10)

1. The electret microphone comprises a shell (1), and a vibrating diaphragm group (3), an insulating gasket (4), a back polar plate (5) and a circuit board (15) which are sequentially arranged and packaged in the shell (1), wherein the back polar plate (5) is electrically connected with the circuit board (15),

the vibrating diaphragm group (3) comprises a diaphragm and a metal ring, the diaphragm is arranged on the metal ring, the frequency range of the diaphragm is 2.5KHZ-3KHZ, and the thickness of the insulating gasket (4) is in direct proportion to the outer diameter of the shell (1).

2. The electret microphone of claim 1 wherein the diaphragm is formed by magnetron sputtering vacuum gold plating.

3. Electret microphone according to claim 1, characterized in that it further comprises a steel mesh (2), which steel mesh (2) is arranged inside the housing (1) below the metal ring.

4. An electret microphone according to any one of claims 1-3, characterized in that the electret microphone further comprises a conducting member between the back-plate (5) and the circuit board (15) for conducting the back-plate (5) and the circuit board (15).

5. The electret microphone of claim 4 wherein the conductive member comprises:

the copper sheet (10) is connected between the first spring (12) and the second spring (13), one end of the first spring (12) is connected with the back electrode plate (5), and one end of the second spring (13) is connected with the circuit board (15).

6. An electret microphone as defined in claim 5, further comprising:

mould chamber (9) and mould ring (14), mould chamber (9) and be located the top of back polar plate (5), mould chamber (9) with mould and encircle and can form the inner chamber between (14), copper sheet (10) set up in mould the top terminal surface in chamber (9).

7. The electret microphone of claim 6 wherein the electret microphone further comprises:

the bolt (8) and the nut (11), the head of bolt (8) butt to the first spring (12) on with the one end of back of the body polar plate (5) not being connected, the tip of bolt (8) passes in proper order mould chamber (9) and copper sheet (10), so that nut (11) screw to the tip of bolt (8).

8. The electret microphone according to claim 7, characterized in that the copper sheet (10) has an annular placement groove (101), the second spring (13) is limited in the annular placement groove (101), and the second spring (13) is covered on the periphery of the nut (11).

9. The electret microphone according to claim 7, characterized in that damping cotton (6) and damping cloth (7) are stacked in the plastic cavity (9), the damping cotton (6) is located above the back plate (5), mounting holes (16) are formed in the centers of the damping cotton (6) and the damping cloth (7), and the first springs (12) are limited in the mounting holes (16).

10. An electret microphone according to any one of claims 1-3, characterized in that the back-plate (5) is provided with sound-transmitting holes (51).