CN113271524B

CN113271524B - Bone conduction microphone

Info

Publication number: CN113271524B
Application number: CN202110823362.0A
Authority: CN
Inventors: 邓旭东; 朱孟; 张俊平; 徐礼果
Original assignee: Jiangxi Lianchuang Sound Macro Electronic Co ltd
Current assignee: Jiangxi Lianchuang Sound Macro Electronic Co ltd
Priority date: 2021-07-21
Filing date: 2021-07-21
Publication date: 2021-10-01
Anticipated expiration: 2041-07-21
Also published as: CN113271524A

Abstract

The invention discloses a bone conduction microphone, belonging to the technical field of audio transmission, comprising: a housing provided with a limit hole; the positioning column is positioned in the center of the shell and matched with the limiting hole to limit free rotation of the positioning column; the central magnet is sleeved on the positioning column; two sets of reverse induction coils which are annularly arranged on the central magnet; one end of the lead is arranged between the two sets of reverse induction coils through an FPC conductive rubber plate so as to fix the two sets of reverse induction coils into a whole, and the other end of the lead penetrates out of the shell; and the suspension parts are symmetrically arranged at two ends of the central magnet. The traditional matching mode of the shell and the positioning column is changed into a triangular or polygonal matching mode from the traditional circular hole matching, so that the deviation of a central magnetic circuit caused by tolerance matching can be effectively reduced, the magnetic gap difference in the symmetrical direction is reduced, and the problem of rubbing caused by the up-and-down vibration of the voice coil is reduced.

Description

Bone conduction microphone

Technical Field

The invention relates to the technical field of audio transmission, in particular to a bone conduction microphone.

Background

The modes of external sound transmission into the inner ear of human body include air conduction and bone conduction. The air conduction means that sound is transmitted to the inner ear through the outer ear and the middle ear, and the bone conduction technology means that a vibration signal is converted into an electric signal by picking up a vibration receiver. Specifically, the bone conduction technology is to attach a pickup vibration receiver to the head or neck of a human body, and utilizes the slight vibration of the head and neck bone caused by the speaking of the human body to collect and convert sound signals into electric signals and output the electric signals. Bone conduction technology does not require air as a sound transmission medium, so that high-definition sound output can still be realized in a strong noise environment.

In order to improve the noise reduction effect of the microphone, in the prior art, a double-voice coil and a suspension symmetric design are adopted, but the adopted double-voice coil is separately arranged or is not well fixed, namely, the double-voice coil is difficult to directly weld and fix, so that when the microphone is used, vibration generated by the voice coil can generate a little phase difference due to delay, and a part of noise is still remained, thereby influencing the use.

Disclosure of Invention

The present invention is directed to solve at least one of the problems of the prior art and to provide a bone conduction microphone.

The technical solution of the invention is as follows:

a bone conduction microphone, comprising:

a housing provided with a limit hole;

the positioning column is positioned in the center of the shell and matched with the limiting hole to limit free rotation of the positioning column;

the central magnet is sleeved on the positioning column;

two sets of reverse induction coils which are arranged on the central magnet in a surrounding manner;

one end of the lead is arranged between the two sets of reverse induction coils through an FPC conductive rubber plate so as to fix the two sets of reverse induction coils into a whole, and the other end of the lead penetrates out of the shell;

and the suspension parts are symmetrically arranged at two ends of the central magnet.

Preferably, the limiting hole is polygonal.

Preferably, the suspension member is arched to form a resilient bladder structure with the counter induction coil.

Preferably, the housing is made of antimagnetic material.

Preferably, the casing is hermetically arranged, and pressure relief micro holes are arranged on the FPC conductive rubber plate and/or the suspension member.

Preferably, an avoiding structure is arranged on the edge of the central magnet.

Preferably, a support part capable of adjusting tone is arranged on the hanging part.

The invention has at least one of the following beneficial effects:

(1) according to the bone conduction microphone, the traditional matching mode of the shell and the positioning column is changed into a polygonal matching mode from the traditional circular hole matching, so that the deviation of a central magnetic circuit caused by tolerance matching can be effectively reduced, the difference of magnetic gaps in the symmetrical direction is reduced, and the problem of rubbing and touching caused by the up-and-down vibration of a voice coil is reduced. The matching mode of polygon is changed, the position of the wire outlet on the FPC conductive rubber plate can be directional, and the problem of free rotation dislocation is avoided.

(2) According to the bone conduction microphone, the two sets of reverse induction coils are integrated into a whole through the FPC conductive rubber plate, so that on one hand, the double coils are communicated, and on the other hand, the linear vibration of the voice coils can be fixed, so that the signal phases on two sides are completely opposite, and the external noise is effectively counteracted.

(3) According to the bone conduction microphone, the suspension piece is arranged in an arch shape to form an elastic air bag structure together with the reverse induction coil, the low-frequency resonance peak K1 is determined by the vibration system, the elastic air bag vibrates to generate the high-frequency resonance peak K2, low-frequency and high-frequency domain modulation is achieved, a good frequency response curve and a good distortion curve are obtained, and the sound fidelity is good.

(4) According to the bone conduction microphone, the shell adopts a sealing technology, unbalance generated by internal and external pressure difference is effectively isolated, and internal air pressure is balanced by the pressure relief micropores, so that the bone conduction microphone can be normally used at low pressure or on plateau.

Drawings

FIG. 1 is a schematic perspective view of a preferred embodiment of the present invention;

FIG. 2 is a front view of the preferred embodiment of the present invention;

FIG. 3 is a bottom view of the preferred embodiment of the present invention;

FIG. 4 is a left side view of the preferred embodiment of the invention;

FIG. 5 is a sectional view A-A of FIG. 4;

FIG. 6 is a schematic view of a central magnet avoiding structure according to the present invention;

FIG. 7 is a diagram of a flexible bladder structure formed by a suspension member according to the present invention;

FIG. 8 is a schematic diagram of audio conditioning of a suspension element according to the present invention;

FIG. 9 is a schematic view of the invention under low pressure conditions with the pressure outside the housing;

FIG. 10 is a first schematic view of the present invention showing the pressure inside the housing in a low pressure environment;

FIG. 11 is a second schematic diagram illustrating the pressure applied to the interior of the housing in a low pressure environment;

in the figure, 100-shell, 101-upper shell, 102-lower shell, 103-limiting hole, 200-positioning column, 300-FPC conductive rubber plate, 400-central magnet, 401-avoiding structure, 500-upper voice coil, 600-lower voice coil, 700-suspension part, 800-pressure relief micropore and 900-elastic air bag structure.

Detailed Description

Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

Referring to fig. 1 to 11, a preferred embodiment of the present invention:

a bone conduction microphone, comprising:

a housing 100 having a stopper hole 103 formed therein;

a positioning post 200 located at the center of the housing 100, wherein the positioning post 200 is matched with the limiting hole 103 to limit free rotation of the positioning post 200;

a central magnet 400 sleeved on the positioning column 200;

two sets of reverse induction coils, including an upper voice coil 500 and a lower voice coil 600 with opposite winding; the coaxial ring is arranged on the central magnet 400;

one end of the lead is arranged between the two sets of reverse induction coils through an FPC conductive rubber plate 300 to fix the two sets of reverse induction coils into a whole, and the other end of the lead penetrates out of the shell 100 and is folded to be close to the shell 100; specifically, a lead wire is embedded in the FPC conductive rubber plate 300, or a groove for placing the lead wire is formed in the FPC conductive rubber plate, the lead wire connects the upper voice coil 500 and the lower voice coil 600, and the FPC conductive rubber plate 300 fixes the upper voice coil 500 and the lower voice coil 600; the reverse induction coil picks up vibration, cuts magnetic induction lines, generates alternating motional electromotive force, and does not need an additional power supply, namely, the slight vibration of the head and neck bones caused by the speaking of a person can enable the shell 100 tightly attached to the head and neck to vibrate therewith, the vibrating shell 100 can then push the air pressure in the shell 100 and enable the suspension to drive the central magnet 400 to vibrate, and the vibrating central magnet 400 can enable the reverse induction coil wound outside the central magnet 400 to generate induced electromotive force due to the change of magnetic flux, so that the additional power supply is not needed.

The suspension members 700 are symmetrically fixed to both ends of the central magnet 400.

This embodiment is through becoming an organic whole with its solid through FPC conductive rubber plate 300 between two sets of reverse induction coils, consequently, should set up and realize that the twin coil communicates with each other on the one hand, can also fix reverse induction coil linear vibration simultaneously, guarantees that the signal phase on both sides is completely opposite, the effectual external noise that has offset, the separation or fixed two voice coils that do not lean on for two coil offset, the signal can not form complete symmetry, thereby noise reduction is relatively poor.

As a preferred embodiment of the present invention, it may also have the following additional technical features:

the limiting hole 103 is polygonal. Specifically, can be triangle-shaped, quadrangle etc. preferably triangle-shaped, change the traditional matching mode of casing 100 with reference column 200, match by traditional circular port and change triangle-shaped or polygon matching mode into, can effectively reduce the central magnetic circuit off normal that the tolerance cooperation leads to, reduce the magnetic gap difference of direction of symmetry to it rubs the problem to reduce the vibration production about the voice coil loudspeaker voice coil, in addition, circular cooperation can 360 free rotations, can't guarantee that FPC conducting rubber plate 300 outlet position corresponds the matching. The mode of triangular or polygonal matching is changed, the position of the FPC wire outlet can have directionality, and the problem of free rotation dislocation does not exist.

The suspension member 700 is arched to form a flexible bladder structure with the counter induction coil. Referring to fig. 8, SPL in fig. 8 is shown as sound pressure level, by arranging the suspension member 700 in an arch shape to form an elastic balloon structure with the counter induction coil, the low frequency resonance peak K1 is determined by the vibration system of the microphone, and the elastic balloon structure 900 vibrates to generate the high frequency resonance peak K2, so that frequency domain modulation of low and high frequencies is realized, a better frequency response curve and distortion curve are obtained, and sound fidelity is better.

The casing 100 is made of antimagnetic materials, specifically, the antimagnetic materials can be magnetic conductive materials such as iron-nickel alloy, soft iron metal-plated thin films and the like, the influence of an external electromagnetic field on the microphone is shielded, the antimagnetic interference performance is excellent, most low-frequency noise is isolated to a certain extent, and the noise is attenuated by signals of a casing part, and part of the noise is reflected and refracted.

The casing 100 is hermetically disposed, and in a specific application, the casing 100 includes an upper casing 101 and a lower casing 102, and the suspension 700 is provided with a pressure relief micro-hole 800. Referring to fig. 9-11, P represents pressure.

In addition, considering that the rigidity of the FPC conductive rubber plate 300 is greater than that of the suspension member 700, the pressure relief micro-hole 800 is easily processed on the FPC conductive rubber plate 300, and the suspension member is not easily damaged in the vibration process, and the pressure relief micro-hole 800 is provided on the FPC conductive rubber plate 300 to balance the air pressure.

Specifically, the stress of the housing 100 is calculated as follows according to F = PS under a low pressure condition of 18.8Kpa, for the upper surface and the side surface pressure difference.

Differential pressure force between the upper surface and the lower surface:

side pressure difference stress:

the simulation upper and lower surfaces are stressed under 4N > 2.323N, the side surfaces are stressed under 8N > 7.134N, the shell is stressed under 18.8Kpa of iron with the thickness of 0.4mm, and the product is deformed under 3.418 multiplied by 10^-5mm, which can be approximately deformed basically and is in a safe range.

The edge of central magnet 400 is provided with dodges structure 401, specifically can be a plurality of breachs also can add limit magnetism at the edge of central magnet 400 for reverse induction coil is changeed and is experienced the change of magnetic flux, effectively improves by the vibration to the conversion efficiency of signal of telecommunication, obtains better sensitivity performance.

In still other applications, the suspension member 700 may be made of different materials or have different shapes to effectively control the resonant frequency and achieve different timbre requirements. The material can be PEEK (polyether ether ketone), TPU (thermoplastic polyurethane elastomer rubber), PEI (polyetherimide), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PAR (thermoplastic engineering plastic), LCP (liquid crystal polymer) and the like, the shape can be a fan-shaped, arc-shaped, wave-shaped, irregular arch-shaped and other support shapes, and the purpose of adjusting the tone color is achieved by controlling the material hardness and the shape design of different support rigidities.

Specifically, the bone conduction microphone described above was subjected to the following experiments in the following environment, and the results of the experiments are shown in the following table.

As can be seen from the above table, the bone conduction microphone of the present invention shows excellent yield in some special environments, and it can be seen that the bone conduction microphone of the present invention is applicable to special environments such as high noise and low pressure, has functions of water resistance, salt mist corrosion resistance, and the like, and is applicable to special fields such as plateau, high altitude, underwater, and the like.

The above additional technical features can be freely combined and used in superposition by those skilled in the art without conflict.

In the description of the embodiments of the present invention, the term "and/or" herein is only one kind of association relationship describing an associated object, and means that there may be three kinds of relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The above description is only a preferred embodiment of the present invention, and the technical solutions that achieve the objects of the present invention by basically the same means are all within the protection scope of the present invention.

Claims

1. A bone conduction microphone, characterized by: the method comprises the following steps:

a housing (100) provided with a locatable limit hole (103);

the positioning column (200) is located at the center of the shell (100), and the positioning column (200) is matched with the limiting hole (103) to limit free rotation of the positioning column (200);

the central magnet (400) is sleeved on the positioning column (200);

two sets of reverse induction coils, including an upper voice coil (500) and a lower voice coil (600) with opposite winding wires; which is arranged around the central magnet (400);

one end of the lead is arranged between the two sets of reverse induction coils through an FPC conductive rubber plate (300) to fix the two sets of reverse induction coils into a whole, and the other end of the lead penetrates out of the shell (100); a lead is embedded in the FPC conductive rubber plate (300), or a groove for placing the lead is arranged on the FPC conductive rubber plate; one end of the lead connects the upper voice coil (500) and the lower voice coil (600), the FPC conductive rubber plate (300) fixes the upper voice coil (500) and the lower voice coil (600), and the other end of the lead penetrates out of a gap on the side wall of the shell along with the FPC conductive rubber plate (300) and is folded to be close to the shell 100;

suspension members (700) symmetrically disposed at both ends of the central magnet (400);

the limiting hole (103) is polygonal.

2. The bone conduction microphone according to claim 1, wherein: the suspension member (700) is arcuately arranged to form a resilient bladder structure (900) with the counter induction coil.

3. The bone conduction microphone according to claim 1, wherein: the shell (100) is made of antimagnetic materials.

4. The bone conduction microphone according to claim 1, wherein: the shell (100) is arranged in a sealing mode, and pressure relief micropores (800) are formed in the FPC conductive rubber plate (300) and/or the suspension piece (700).

5. The bone conduction microphone according to claim 1, wherein: an avoiding structure (401) is arranged on the edge of the central magnet (400).

6. The bone conduction microphone according to claim 1, wherein: the hanging piece (700) is provided with a supporting part capable of adjusting tone.