Bone conduction microphone

Abstract

A bone conduction microphone, comprising: a circuit board, which has an acoustic channel; a housing, which is connected to the circuit board in a covering manner to form an accommodating space; a metal cover, which is arranged in the accommodating space and is connected to the circuit board in a covering manner to form a first cavity, wherein the metal cover comprises a top wall spaced apart from the circuit board and a side wall located between the top wall and the circuit board; a vibration assembly, which is arranged in the accommodating space and is connected to the top wall in a covering manner to form a second cavity, wherein the vibration assembly comprises a vibration member spaced apart from the top wall and a spacer located between the vibration member and the top wall, and the housing, the vibration assembly, the metal cover and the circuit board enclose to form a first conduction cavity; and an MEMS chip, which is arranged in the first cavity and is fixed to the circuit board, wherein the MEMS chip has a back cavity, the acoustic channel communicates the first conduction cavity with the back cavity, and vibration of the vibration member is conducted to one side of the MEMS chip through the first conduction cavity, the acoustic channel and the back cavity. The bone conduction microphone can reduce the impact of electromagnetic interference and improve the signal-to-noise ratio.

Description

bone conduction microphone Technical Field

[0001] The utility model relates to the field of sound-to-electricity conversion, in particular to a bone conduction microphone. Background Art

[0002] Bone conduction microphones convert the slight vibrations of the head and neck bones caused by speaking into electrical signals. Unlike traditional microphones, which collect sound through air conduction, bone conduction microphones can reproduce sound with high clarity even in noisy environments, avoiding the noise interference caused by airborne sound and ensuring extremely high sound quality. However, related bone conduction microphones suffer from insufficient signal-to-noise ratio due to electromagnetic interference affecting the MEMS and ASIC chips within them. Technical issues

[0003] Therefore, it is necessary to provide a new bone conduction microphone to solve the above technical problems. Technical Solutions

[0004] The purpose of the present invention is to overcome the above technical problems and provide a bone conduction microphone that can reduce the influence of electromagnetic interference and improve the signal-to-noise ratio.

[0005] In order to achieve the above object, the present invention provides a bone conduction microphone, comprising:

[0006] a circuit board having an acoustic channel;

[0007] A housing connected to the circuit board cover to form a receiving space;

[0008] A metal cover is disposed in the receiving space and connected to the circuit board to form a first cavity, the metal cover comprising a top wall spaced apart from the circuit board and a side wall located between the top wall and the circuit board;

[0009] a vibration assembly disposed in the receiving space and connected to the top wall to form a second cavity, the vibration assembly comprising a vibration member spaced apart from the top wall and a spacer located between the vibration member and the top wall, the housing, the vibration assembly, the metal cover, and the circuit board enclosing a first conduction cavity;

[0010] A MEMS chip is disposed in the first cavity and fixed to the circuit board. The MEMS chip has a back cavity. The acoustic channel connects the first conduction cavity and the back cavity. The vibration of the vibrating element is conducted to one side of the MEMS chip via the first conduction cavity, the acoustic channel, and the back cavity.

[0011] Preferably, the top wall is provided with a connecting hole connecting the first cavity and the second cavity, the first cavity, the connecting hole and the second cavity form a second conduction cavity, and the vibration of the vibrating member is also conducted to the other side of the MEMS chip through the second conduction cavity.

[0012] Preferably, the top wall is a metal plate with a porous structure, the porous structure is arranged in an array, and the connecting holes are the porous structure.

[0013] Preferably, the top wall is a metal mesh, and the connecting holes are mesh holes of the metal mesh.

[0014] Preferably, the metal cover is an integrally formed structure, or the metal cover is formed by fixedly connecting the top wall and the side walls.

[0015] Preferably, the vibration member includes a vibration membrane fixed to the spacer and a mass block fixed on the vibration membrane.

[0016] Preferably, the bone conduction microphone further includes an ASIC chip electrically connected to the MEMS chip, and the ASIC chip is disposed in the first cavity and fixed to the circuit board.

[0017] Preferably, the shell is a metal shell.

[0018] Preferably, the spacer is a portion of the top wall, and a protrusion of the top wall extending in a direction away from the circuit board forms the spacer.

[0019] Preferably, the spacer is a part of the vibration membrane, and a protrusion of the vibration membrane extending in a direction close to the circuit board forms the spacer.

[0020] Preferably, the vibration membrane is a breathable membrane.

[0021] Preferably, the MEMS chip includes a diaphragm, and the diaphragm is a gas-permeable membrane. Beneficial effects

[0022] In this bone conduction microphone, the metal cover acts as an electromagnetic shield, reducing the impact of electromagnetic interference on the MEMS and ASIC chips, thereby improving the signal-to-noise ratio of the bone conduction microphone. Furthermore, the top wall of the metal cover protects the MEMS and ASIC chips from impacts caused by vibrating components, thereby improving the reliability of the bone conduction microphone. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art in the field of the present invention, other drawings can be obtained based on these drawings without creative work. Among them:

[0024] FIG1 is a schematic structural diagram of a bone conduction microphone of the present invention;

[0025] FIG2 is a schematic structural diagram of the top wall of the metal cover of the bone conduction microphone of the present invention;

[0026] FIG3 is a schematic structural diagram of another bone conduction microphone of the present invention. Best Mode for Carrying Out the Invention

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field of the present invention without making creative efforts are within the scope of protection of the present invention.

[0028] Referring to FIG. 1 , the present invention provides a bone conduction microphone 100 , which includes a circuit board 1 having an acoustic channel 10 , a housing 2 covering the circuit board 1 to form a receiving space, a metal cover 3 disposed within the receiving space and covering the circuit board 1 to form a first cavity 30 , a vibration assembly 4 disposed within the receiving space, and a MEMS chip 5 having a back cavity 50 disposed within the first cavity 30 and fixed to the circuit board 1 .

[0029] The metal cover 3 includes a top wall 31 spaced apart from the circuit board 1 and a side wall 32 located between the top wall 31 and the circuit board 1 .

[0030] The vibration assembly 4 includes a vibration member 41 spaced apart from the top wall 31 and a spacer 42 located between the vibration member 41 and the top wall 31. The vibration assembly 4 and the top wall 31 are covered to form a second cavity 40.

[0031] The housing 2, the vibration assembly 4, the metal cover 3, and the circuit board 1 collectively form a first conduction cavity 101. The acoustic channel 10 connects the first conduction cavity 101 and the back cavity 50. The vibration of the vibrating element 41 is conducted to one side of the MEMS chip 5 via the first conduction cavity 101, the acoustic channel 10, and the back cavity 50.

[0032] The vibrating member 41 includes a vibrating membrane 411 fixed to the spacer 42 and a mass block 412 fixed to the vibrating membrane 411, wherein the mass block 412 is fixed below the vibrating membrane 411. In the embodiment shown in FIG3 , the mass block 412 can also be fixed above the vibrating membrane 411. As an alternative, the vibrating membrane 411 can be a breathable membrane. The breathable membrane can be formed by making the membrane body of the vibrating membrane 411 from a breathable material, or by providing the vibrating membrane 411 with a breathable structure. The breathable structure is not limited to holes, gaps, incisions, movable valves, etc.

[0033] The bone conduction microphone 100 further includes an ASIC chip 6 electrically connected to the MEMS chip 5. The ASIC chip 6 is disposed within the first cavity 30 and fixed to the circuit board 1. In other embodiments, the ASIC chip 6 may also be fixed to the metal cover 3 or integrated with the MEMS chip 5.

[0034] The metal cover 3 can act as an electromagnetic shield, thereby reducing the impact of electromagnetic interference on the MEMS chip 5 and the ASIC chip 6, and improving the signal-to-noise ratio of the bone conduction microphone 100. In addition, the top wall 31 can also protect the MEMS chip 5 and the ASIC chip 6 from the impact of the vibrating element 41, thereby improving the reliability of the bone conduction microphone 100.

[0035] As an option, the housing 2 may be a metal shell, thereby further improving the electromagnetic shielding effect and increasing the overall structural strength of the bone conduction microphone 100 .

[0036] As an option, the metal cover 3 may be an integrally formed structure, or the metal cover 3 may be formed by fixing the top wall 31 and the side wall 32 together, and the fixing connection may be achieved by welding or gluing.

[0037] Alternatively, the top wall 31 may be a non-porous wall structure, or it may be provided with a connecting hole 311 connecting the first cavity 30 and the second cavity 40. In this embodiment, the first cavity 30, the connecting hole 311, and the second cavity 40 form a second conduction cavity 102. The vibration of the vibrating element 41 is also transmitted to the other side of the MEMS chip 5 via the second conduction cavity 102, thereby improving the sensitivity of the bone conduction microphone 100 through a differential method. In the embodiment shown in Figure 2, the top wall 31 may be a metal plate having a porous structure 3111 arranged in an array, and the connecting holes 311 are the porous structures 3111. In other embodiments, the top wall 31 may be a metal mesh, and the connecting holes 311 are the mesh holes of the metal mesh. It should be noted here that the number of the connecting holes 311 can be a single hole, a double hole, or multiple holes with more than two holes. The present invention does not limit the number, position, shape, size, formation method and arrangement method of the connecting holes 311, as long as they can connect the first cavity 30 and the second cavity 40.

[0038] As an optional method, the MEMS chip 5 includes a diaphragm 51, and the diaphragm 51 can be a breathable membrane. The breathable membrane can be formed by making the membrane body of the diaphragm 51 of a breathable material, or the diaphragm 51 is provided with a breathable structure, and the breathable structure is not limited to holes, gaps, incisions, movable valves, etc.

[0039] As an option, the spacer 42 can be an independent frame structure, or the spacer 42 can also be a part of the top wall 31, and the protrusion of the top wall 31 extending away from the circuit board 1 forms the spacer 42, or the spacer 42 can be a part of the vibration membrane 411, and the protrusion of the vibration membrane 411 extending in the direction close to the circuit board 1 forms the spacer 42.

[0040] The above is only an implementation method of the present invention. It should be pointed out that for ordinary technicians in the field of the present invention, improvements can be made without departing from the creative concept of the present invention, but these all fall within the scope of protection of the present invention.

Claims

1. A bone conduction microphone, characterized in that: include: a circuit board having an acoustic channel; A housing connected to the circuit board cover to form a receiving space; A metal cover is disposed in the receiving space and connected to the circuit board to form a first cavity, the metal cover comprising a top wall spaced apart from the circuit board and a side wall located between the top wall and the circuit board; a vibration assembly disposed in the receiving space and connected to the top wall to form a second cavity, the vibration assembly comprising a vibration member spaced apart from the top wall and a spacer located between the vibration member and the top wall, the housing, the vibration assembly, the metal cover, and the circuit board enclosing a first conduction cavity; A MEMS chip is disposed in the first cavity and fixed to the circuit board. The MEMS chip has a back cavity. The acoustic channel connects the first conduction cavity and the back cavity. The vibration of the vibrating element is conducted to one side of the MEMS chip via the first conduction cavity, the acoustic channel, and the back cavity.

2. The bone conduction microphone according to claim 1, wherein The top wall is provided with a connecting hole connecting the first cavity and the second cavity. The first cavity, the connecting hole and the second cavity form a second conduction cavity. The vibration of the vibrating member is also conducted to the other side of the MEMS chip through the second conduction cavity.

3. The bone conduction microphone according to claim 2, wherein: The top wall is a metal plate with a porous structure, the porous structure is arranged in an array, and the communicating holes are the porous structure.

4. The bone conduction microphone according to claim 2, wherein: The top wall is a metal mesh, and the communicating holes are mesh holes of the metal mesh.

5. The bone conduction microphone according to claim 1, wherein The metal cover is an integrally formed structure, or the metal cover is formed by fixedly connecting the top wall and the side walls.

6. The bone conduction microphone according to claim 1, wherein The vibration member includes a vibration membrane fixed to the spacer and a mass block fixed on the vibration membrane.

7. The bone conduction microphone according to claim 1, wherein The bone conduction microphone further includes an ASIC chip electrically connected to the MEMS chip. The ASIC chip is disposed in the first cavity and fixed to the circuit board.

8. The bone conduction microphone according to claim 1, wherein The shell is a metal shell.

9. The bone conduction microphone according to claim 1, wherein The spacer is a portion of the top wall, and a protrusion of the top wall extending in a direction away from the circuit board forms the spacer.

10. The bone conduction microphone according to claim 6, wherein The spacer is a portion of the vibration membrane, and a protrusion of the vibration membrane extending in a direction close to the circuit board forms the spacer.

11. The bone conduction microphone according to claim 6, wherein The vibration membrane is a breathable membrane.

12. The bone conduction microphone according to claim 1, wherein The MEMS chip includes a diaphragm, which is a gas-permeable membrane.

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