WO2022000853A1 - 振动传感器 - Google Patents

振动传感器 Download PDF

Info

Publication number
WO2022000853A1
WO2022000853A1 PCT/CN2020/121276 CN2020121276W WO2022000853A1 WO 2022000853 A1 WO2022000853 A1 WO 2022000853A1 CN 2020121276 W CN2020121276 W CN 2020121276W WO 2022000853 A1 WO2022000853 A1 WO 2022000853A1
Authority
WO
WIPO (PCT)
Prior art keywords
cavity
diaphragm
circuit board
vibration sensor
hole
Prior art date
Application number
PCT/CN2020/121276
Other languages
English (en)
French (fr)
Inventor
曾鹏
胡恒宾
Original Assignee
瑞声声学科技(深圳)有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 瑞声声学科技(深圳)有限公司 filed Critical 瑞声声学科技(深圳)有限公司
Publication of WO2022000853A1 publication Critical patent/WO2022000853A1/zh

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R19/00—Electrostatic transducers

Definitions

  • the utility model relates to the field of acoustic-electrical conversion, in particular to a vibration sensor used for bone conduction electronic products.
  • Vibration sensors are used to convert vibration signals into electrical signals.
  • Existing MEMS vibration sensors include a diaphragm assembly as a vibration sensing device and a MEMS microphone as a vibration detection device that converts vibration signals into electrical signals.
  • the vibration sensing device and the vibration detection device are integrated together, and because the MEMS microphone adopts piezoelectric or capacitive sensing, it can only be sensed under the condition of direct pressure contact, making it sensitive to low-frequency vibration less than 500Hz, but not sensitive to low-frequency vibration.
  • the high-frequency vibration greater than 1KHz has poor response and poor performance in the field of audio equipment.
  • the purpose of the utility model is to provide a vibration sensor with high sensitivity and good reliability.
  • the utility model provides a vibration sensor, which includes:
  • circuit board encloses a receiving cavity, and one side of the circuit board is provided with a through hole passing through it;
  • the casing cover is fixed on the circuit board and covers the through hole, the casing and the circuit board together form a resonant cavity, and the casing is provided with a first pressure relief hole passing through it;
  • a MEMS microphone the MEMS microphone is accommodated in the accommodating cavity and is electrically connected to the circuit board, the MEMS microphone comprises a base fixed on the circuit board and having a back cavity, and is supported on the base away from a first diaphragm and a back plate at one end of the through hole; the base surrounds the through hole and makes the back cavity communicate with the through hole; the first diaphragm and the back plate are spaced apart forming a capacitive structure; and,
  • the diaphragm assembly is accommodated in the resonant cavity and divides the resonant cavity into a first cavity and a second cavity, and the first cavity is communicated with the back cavity through the through hole;
  • the diaphragm assembly is provided with a second pressure relief hole therethrough, and the first cavity communicates with the second cavity through the second pressure relief hole;
  • the diaphragm assembly vibrates and changes the air pressure in the resonant cavity.
  • the vibration sensor further includes an ASIC chip, and the ASIC chip is accommodated in the accommodating cavity and is electrically connected to the MEMS microphone.
  • the circuit board includes a bottom plate and a surrounding wall extending from the bottom plate in a direction close to the casing and surrounding the receiving cavity, and the casing is fixed to the bottom plate and is spaced from the surrounding wall.
  • the casing includes a casing plate spaced apart from the circuit board and a side plate that is bent and extended toward the circuit board from a peripheral edge of the casing plate and fixed to the circuit board.
  • the pressing hole penetrates the outer shell plate.
  • the diaphragm assembly includes a gasket fixed on the circuit board and arranged around the through hole, and a second diaphragm fixed on the side of the gasket away from the through hole, the gasket, The second diaphragm and the circuit board together form the first cavity, and the second pressure relief hole penetrates the second diaphragm.
  • the diaphragm assembly further includes a mass block fixedly connected to the second diaphragm; the mass block is attached to a side of the second diaphragm close to the first cavity and/or the The second diaphragm is close to one side of the second cavity.
  • the mass blocks located on the same side of the second diaphragm include a plurality of mass block units spaced apart from each other.
  • the diaphragm assembly further includes a mass block wrapped and fixed by the second diaphragm.
  • the second diaphragm includes two second diaphragms fixed on the spacer and stacked on each other, and the mass block is sandwiched and wrapped between the two second diaphragms.
  • the orthographic projection area of the first diaphragm on the circuit board along the vibration direction is smaller than the orthographic projection area of the second diaphragm on the circuit board along the vibration direction.
  • a receiving cavity is formed by the circuit board, a through hole is provided on one side of the circuit board, and a MEMS microphone is arranged in the receiving cavity;
  • a resonant cavity is formed, the casing is provided with a first pressure relief hole passing through it, a diaphragm assembly is arranged in the resonant cavity to separate the resonant cavity into a first cavity and a second cavity, and the first cavity passes through the cavity.
  • the hole is communicated with the back cavity;
  • the diaphragm assembly is provided with a second pressure relief hole passing through it, and the first cavity is communicated with the second cavity through the second pressure relief hole;
  • the MEMS microphone comprises a a base with a back cavity, a first vibrating film supported on the base and a back plate; the base surrounds the through hole and makes the back cavity communicate with the through hole; the through hole connects the The first cavity communicates with the back cavity.
  • the diaphragm assembly is accommodated in the resonant cavity surrounded by the casing and the circuit board, and its shielding effect is better, and the volume of the cavity used for air pressure changes becomes larger, and the vibration effect is better; while the MEMS The microphone can better sense the vibration generated by the diaphragm assembly, and convert the sensed vibration signal into an electrical signal, so as to achieve better vibration response to both high-frequency and low-frequency vibrations transmitted by the resonant cavity, effectively improving the sensitivity. .
  • Fig. 1 is the structural representation of the vibration sensor of the utility model
  • Fig. 2 is the exploded schematic diagram of the vibration sensor of the utility model
  • Fig. 3 is the sectional view along A-A of Fig. 1;
  • FIG. 4 is a schematic structural diagram of a second embodiment of the fixing method of the mass block and the second diaphragm of the vibration sensor in FIG. 1;
  • FIG. 5 is a schematic structural diagram of a third embodiment of the fixing mode of the mass block and the second diaphragm of the vibration sensor in FIG. 1;
  • FIG. 6 is a schematic structural diagram of another embodiment after the structure of the mass block in FIG. 5 is changed;
  • FIG. 7 is a schematic structural diagram of the fourth embodiment of the fixing method of the mass block and the diaphragm in the vibration sensor of the present invention.
  • the present invention provides a vibration sensor 100 , which includes a circuit board 1 , a housing 2 , a MEMS microphone 3 and a diaphragm assembly 4 .
  • the circuit board 1 encloses a receiving cavity 10 , and one side of the circuit board 1 is provided with a through hole 11 extending therethrough.
  • the circuit board 1 is designed to be a hollow three-dimensional structure, and the receiving cavity 10 is formed inside the circuit board 1 .
  • the circuit board 1 includes a bottom plate 12 and a surrounding wall 13 extending from the bottom plate 12 toward the casing 2 and surrounding the receiving cavity 10 .
  • the casing 2 is fixed to the bottom plate 12 and spaced from the surrounding wall 13 .
  • the circuit board 1 may be integrally formed, that is, a circuit board 1 with a receiving cavity 10 disposed in the middle; or two upper and lower layers of circuit boards together form a receiving cavity, such as the sandwich structure in this embodiment.
  • the casing 2 is covered and fixed on the circuit board 1 and covers the through hole 11 , and the casing 2 and the circuit board 1 together enclose a resonant cavity 20 . That is, the through hole 11 communicates with the resonant cavity 20 .
  • the casing 2 includes a casing plate 21 that is spaced apart from the circuit board 1 and a side that is bent and extended toward the circuit board 1 from the peripheral edge of the casing plate 21 and is fixed to the bottom plate 12 . plate 22.
  • the MEMS (Microelectro Mechanical Systems) microphone 3 that is, a micro-electromechanical system microphone, is accommodated in the accommodating cavity 10 and is electrically connected to the circuit board 1 .
  • the MEMS microphone 3 is shielded by the circuit board 1 and the outer shell 2 to improve its electromagnetic shielding effect and prevent interference from other electronic components.
  • the MEMS microphone 3 includes a base 31 fixed on the circuit board 1 and having a back cavity 30 , a first diaphragm 32 and a back plate 33 supported on an end of the base 31 away from the through hole 11 .
  • the first diaphragm 32 and the back plate 33 are spaced apart to form a capacitance structure.
  • the capacitance generated by the MEMS microphone 3 can be changed, thereby Realize changes in electrical signals.
  • the base 31 surrounds the through hole 11 and makes the back cavity 30 communicate with the through hole 11 .
  • the diaphragm assembly 4 is accommodated in the resonant cavity 20 and divides the resonant cavity 20 into a first cavity 201 and a second cavity 202 .
  • the first cavity 201 is connected to the back cavity through the through hole 11 . 30 connections.
  • the vibration sensor 100 When the vibration sensor 100 inputs a vibration signal or a pressure signal, for example, the side of the casing 2 facing away from the resonant cavity 20 and/or the side of the circuit board 1 facing away from the receiving cavity 10 is input with a vibration signal or pressure.
  • the vibration component 4 When the signal is received, the vibration component 4 vibrates and causes the air pressure in the resonant cavity 20 to change.
  • the change in air pressure causes the vibration of the first diaphragm 32 of the MEMS microphone 3 , which changes the distance between the first diaphragm 32 and the back plate 33 , that is, changes the capacitance generated by the MEMS microphone 3 .
  • the vibration signal into an electrical signal
  • the MEMS microphone 3 converts the external input vibration signal or pressure signal into an electrical signal, and realizes the conversion of the vibration signal into an electrical signal.
  • the side of the circuit board 1 and/or the casing 2 of the vibration sensor 100 is attached to the neck, and when a person speaks, the bone conduction transmits the vibration signal, so as to realize the above transformation process.
  • the MEMS microphone 3 detects the external input vibration signal through the internal air pressure change caused by the vibration of the diaphragm assembly 4, so that the MEMS microphone 3 can ensure the accurate detection of the air pressure change to the greatest extent, especially for high frequencies greater than 1KHz.
  • the vibration also has an accurate response, which effectively improves the sensitivity and reliability of the vibration sensor 100 .
  • the performance of the MEMS microphone 3 is relatively stable under different temperature conditions, its sensitivity is basically not affected by factors such as temperature, vibration, temperature and time, and the reliability is good and the stability is high. Because the MEMS microphone 3 can be subjected to high temperature reflow soldering at 260° C. and the performance is not affected, the basic performance with high accuracy can still be achieved without the audio debugging process after assembly.
  • the vibration sensor further includes an ASIC (Application Specific Integrated Circuit) chip 5 , and the ASIC chip 5 is accommodated in the accommodation cavity 10 and It is electrically connected with the MEMS microphone 3 .
  • the ASIC chip 5 provides an external bias for the MEMS microphone 3, and an effective bias will enable the MEMS microphone 3 to maintain stable acoustic sensitivity and electrical parameters in the entire operating temperature range, and can also support different sensitivities
  • the microphone structure design is more flexible and reliable.
  • the outer casing 2 is provided with a first pressure relief hole 23 penetrating through it.
  • the first pressure relief hole 23 is provided through the outer casing plate 21 , and the whole machine is SMT (ie surface mount technology)
  • SMT surface mount technology
  • the arrangement of the first pressure relief hole 23 plays the role of balancing the air pressure.
  • the shell plate 21 is attached and fixed to the interior of the mobile device through surface assembly technology, and the first pressure relief hole 23 is blocked to seal the resonant cavity 20, which effectively avoids the interference of external air-conducting acoustic signals, and further The bone conduction sensitivity and frequency characteristics of the vibration sensor 100 are improved.
  • the position and number of the first pressure relief holes 23 are not limited to this, and the principles are the same.
  • the diaphragm assembly 4 is provided with a second pressure relief hole 40 therethrough, and the first cavity 201 communicates with the second cavity 202 through the second pressure relief hole 40 to balance all the The air pressures of the second cavity 202 and the first cavity 201 are balanced, that is, the air pressures of the second cavity 202 and the back cavity 30 are balanced.
  • the diaphragm assembly 4 includes a gasket 41 fixed on the circuit board 1 and disposed around the through hole 11 and a second diaphragm fixed on the side of the gasket 41 away from the through hole 11 42.
  • the spacer 41 , the second diaphragm 42 and the circuit board 1 together form the first cavity 201 . That is, the spacer 41 is used to space the second diaphragm 42 from the circuit board 1 to provide a vibration space.
  • the spacer 41 can also be integrally formed with the second diaphragm 42 .
  • the second pressure relief hole 40 is disposed through the second diaphragm 42 .
  • the position of the second pressure relief hole 40 is not limited to this, and the principle is the same.
  • the diaphragm assembly 4 further includes a mass block 43 fixedly connected to the second diaphragm 42 .
  • the mass block 43 is attached to the side of the second diaphragm 42 close to the first cavity 201 and/or the side of the second diaphragm 42 close to the second cavity 202 .
  • the diaphragm assembly 4 is accommodated in the resonant cavity 20 surrounded by the casing 2 and the circuit board 1, and its shielding effect is better. At the same time, the volume of the cavity for air pressure changes becomes larger, and the vibration effect is better.
  • the mass block 43 is attached to the side of the second diaphragm 42 close to the second cavity 202 .
  • the mass block 43 , the second diaphragm 42 and the spacer 41 are all located in the resonant cavity 20 of the circuit board 1 , which saves space and facilitates production.
  • the orthographic projection area of the first diaphragm 32 on the circuit board 1 along the vibration direction is smaller than the orthographic projection area of the second diaphragm 42 on the circuit board 1 along the vibration direction.
  • the contact area between the second diaphragm 42 and the gas in the resonant cavity 20 is larger, so that it can vibrate the gas better, and the area of the first diaphragm 32 is relatively small, so that the MEMS microphone 3 will be affected by the MEMS microphone 3 installed on the same PCB. Speaker-induced PCB noise results in lower vibration coupling, better acoustic performance, and ease of use.
  • FIG. 4 is a schematic structural diagram of the second embodiment of the fixing mode of the mass block and the second diaphragm of the vibration sensor in the embodiment of FIG. 1 .
  • the difference between the vibration sensor 200 of this embodiment is that the mass block 243 is attached to the side of the second diaphragm 242 close to the first cavity 2101 .
  • the modification of this embodiment reduces the occupation of the volume of the second cavity 2102 by the mass 243 , increases the volume of the second cavity 2102 , and further improves the sensitivity of the vibration sensor 200 .
  • the basis is the same as that of the above-mentioned embodiment shown in FIG. 1 , and details are not repeated here.
  • FIG. 5 is a schematic structural diagram of the third embodiment of the fixing method of the mass block and the second diaphragm of the vibration sensor in FIG. 1 .
  • the difference between the vibration sensor 300 of this embodiment is that the mass block 343 is attached to the side of the second diaphragm 342 close to the first cavity 3101 and the second diaphragm 342 is close to the second diaphragm 342 one side of cavity 3102. That is, the mass blocks 343 include two groups, which are respectively attached to opposite sides of the second diaphragm 342 .
  • This structural design further increases the inertia of the vibration component 34, thereby further improving the sensitivity.
  • the basis is the same as that of the above-mentioned embodiment shown in FIG. 1 , and details are not repeated here.
  • FIG. 6 is a schematic structural diagram of another embodiment after the structure of the mass block in FIG. 3 is changed.
  • the mass 443 located on the same side of the second diaphragm 442 includes a plurality of mass units 4431 spaced apart from each other.
  • This structural design is also designed to increase the inertia of the diaphragm assembly 44, and the diaphragm assembly 44 is more likely to vibrate, so as to further improve the sensitivity.
  • the basis is the same as that of the above-mentioned embodiment shown in FIG. 3 , and details are not repeated here.
  • FIG. 7 is a schematic structural diagram of the fourth embodiment of the fixing method of the mass block and the diaphragm in the vibration sensor of the present invention. Compared with other embodiments of the present invention, the main difference is that the mass block 543 is wrapped by the second diaphragm 542 to form a fixation.
  • the second diaphragm 542 includes two second sub-diaphragms 5421 fixed on the spacer 541 and stacked on each other, and the mass block 543 is sandwiched and wrapped around the two second sub-diaphragms Between 5421.
  • This structural design increases the fixing strength of the mass block 543 and further improves the reliability.
  • a receiving cavity is formed by the circuit board, a through hole is provided on one side of the circuit board, and a MEMS microphone is arranged in the receiving cavity;
  • a resonant cavity is formed, the casing is provided with a first pressure relief hole passing through it, a diaphragm assembly is arranged in the resonant cavity to separate the resonant cavity into a first cavity and a second cavity, and the first cavity passes through the cavity.
  • the hole is communicated with the back cavity;
  • the diaphragm assembly is provided with a second pressure relief hole passing through it, and the first cavity is communicated with the second cavity through the second pressure relief hole;
  • the MEMS microphone comprises a a base with a back cavity, a first vibrating film supported on the base and a back plate; the base surrounds the through hole and makes the back cavity communicate with the through hole; the through hole connects the The first cavity communicates with the back cavity.
  • the diaphragm assembly is accommodated in the resonant cavity surrounded by the casing and the circuit board, and its shielding effect is better, and the volume of the cavity used for air pressure changes becomes larger, and the vibration effect is better; while the MEMS The microphone can better sense the vibration generated by the diaphragm assembly, and convert the sensed vibration signal into an electrical signal, so as to achieve better vibration response to both high-frequency and low-frequency vibrations transmitted by the resonant cavity, effectively improving the sensitivity. .

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
  • Micromachines (AREA)

Abstract

本实用新型提供了一种振动传感器，其包括电路板，电路板具有收容腔且设有通孔；外壳盖设固定于电路板并覆盖通孔，外壳与电路板围成谐振腔，外壳设有第一泄压孔；MEMS麦克风，收容于收容腔内与电路板电性连接，其包括固定于电路板且具有背腔的基座、支撑于基座的第一振膜和背极板；基座环绕通孔使背腔与通孔连通；第一振膜与背极板间隔形成电容结构；振膜组件，振膜组件将谐振腔分隔成第一腔和第二腔，第一腔经通孔与背腔连通；振膜组件设有第二泄压孔，第一腔通过第二泄压孔与第二腔连通；振动传感器输入振动信号或压力信号时，振膜组件振动，并使谐振腔内的气压产生变化。与相关技术相比，本实用新型的振动传感器灵敏度更高，可靠性更好

Description

振动传感器 技术领域
本实用新型涉及声电转换领域，尤其涉及一种用于骨传导电子产品的振动传感器。
 背景技术
振动传感器，用于将振动信号转化为电信号。目前现有的MEMS振动传感器包括作为振动感应装置的振膜组件以及将振动信号转化为电信号的作为振动检测装置的MEMS麦克风。
 技术问题
由于振动感应装置和振动检测装置均集成于一起，并且由于MEMS麦克风采用压电或电容式感应，在受到压力直接挤压接触的情况下才能感应，使得其对小于500Hz的低频振动敏感，但对大于1KHz的高频振动响应差，应用于音频设备领域的性能较差。
因此，实有必要提供一种新的振动传感器解决上述技术问题。
 技术解决方案
本实用新型的目的在于提供一种灵敏度高、可靠性好的振动传感器。
为了达到上述目的，本实用新型提供了一种振动传感器，其包括：
电路板，所述电路板围成收容腔，所述电路板的其中一侧设有贯穿其上的通孔；
外壳，所述外壳盖设固定于所述电路板并覆盖所述通孔，所述外壳与所述电路板共同围成谐振腔，所述外壳设有贯穿其上的第一泄压孔；
MEMS麦克风，所述MEMS麦克风收容于所述收容腔内并与所述电路板电性连接，所述MEMS麦克风包括固定于所述电路板且具有背腔的基座、支撑于所述基座远离所述通孔一端的第一振膜和背极板；所述基座环绕所述通孔并使所述背腔与所述通孔连通；所述第一振膜与所述背极板间隔形成电容结构；以及，
振膜组件，所述振膜组件收容于所述谐振腔内并将所述谐振腔分隔成第一腔和第二腔，所述第一腔通过所述通孔与所述背腔连通；所述振膜组件设有贯穿其上的第二泄压孔，所述第一腔通过所述第二泄压孔与所述第二腔连通；
所述振动传感器输入振动信号或压力信号时，所述振膜组件振动，并使所述谐振腔内的气压产生变化。
优选的，所述振动传感器还包括ASIC芯片，所述ASIC芯片收容于所述收容腔内并与所述MEMS麦克风电性连接。
优选的，所述电路板包括底板以及自底板向靠近所述外壳方向延伸并围设成所述收容腔的围壁，所述外壳固定于所述底板且与所述围壁间隔。
优选的，所述外壳包括与所述电路板间隔相对的外壳板和由所述外壳板的周缘向所述电路板方向弯折延伸并固定于所述电路板的侧板，所述第一泄压孔贯穿所述外壳板。
优选的，所述振膜组件包括固定于所述电路板并环绕所述通孔设置的垫片以及固定于所述垫片远离所述通孔一侧的第二振膜，所述垫片、所述第二振膜及所述电路板共同围成所述第一腔，所述第二泄压孔贯穿所述第二振膜。
优选的，所述振膜组件还包括与所述第二振膜固定连接的质量块；所述质量块贴设于所述第二振膜靠近所述第一腔的一侧和/或所述第二振膜靠近所述第二腔的一侧。
优选的，位于所述第二振膜同一侧的所述质量块包括多个相互间隔设置质量块单元。
优选的，所述振膜组件还包括由所述第二振膜包裹固定的质量块。
优选的，所述第二振膜包括固定于所述垫片并相互叠设的两个第二子振膜，所述质量块夹设包裹于两个所述第二子振膜之间。
优选的，所述第一振膜沿其振动方向向所述电路板上的正投影面积小于所述第二振膜沿其振动方向向所述电路板上的正投影面积。
 有益效果
与相关技术相比，本实用新型的振动传感器中，通过所述电路板围成收容腔，并在所述电路板的一侧设通孔，在收容腔内设置MEMS麦克风；通过设置所述外壳与所述电路板共同围成谐振腔，外壳设有贯穿其上的第一泄压孔，谐振腔内设置振膜组件以将谐振腔分隔成第一腔和第二腔，第一腔通过通孔与背腔连通；所述振膜组件设有贯穿其上的第二泄压孔，第一腔通过第二泄压孔与第二腔连通；所述MEMS麦克风包括固定于所述电路板且具有背腔的基座、支撑于基座的第一振膜和背极板；所述基座环绕所述通孔并使所述背腔与所述通孔连通；所述通孔将所述第一腔与所述背腔连通。通过上述结构设计，所述振膜组件收容于由外壳和电路板围成的谐振腔内，其屏蔽效果更好，同时用于发生气压变化的腔体体积变大，振动效果更好；而MEMS麦克风可更好的感应由振膜组件产生的振动，并将感应的振动信号转化为电信号，从而实现对谐振腔传递的高频振动和低频振动均具有更好的振动响应，有效提高了灵敏度。
 附图说明
为了更清楚地说明本实用新型实施例中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本实用新型的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其它的附图，其中：
图1为本实用新型振动传感器的结构示意图；
图2为本实用新型振动传感器的分解示意图；
图3为图1沿A-A的剖视图；
图4为图1中振动传感器的质量块与第二振膜固定方式的第二实施方式结构示意图；
图5为图1中振动传感器的质量块与第二振膜固定方式的第三实施方式结构示意图；
图6为图5中质量块结构变化后的另一实施方式结构示意图；
图7为本实用新型振动传感器中质量块与振膜固定方式的第四实施方式结构示意图。
 本发明的实施方式
下面将结合本实用新型实施例中的附图，对本实用新型实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅是本实用新型的一部分实施例，而不是全部的实施例。基于本实用新型中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其它实施例，都属于本实用新型保护的范围。
需要说明的是，各实施例之间的技术方案可相互组合，但必须是以本领域普通技术人员能够实现为基础。
请参阅图1-3所示，本实用新型提供了一种振动传感器100，其包括电路板1、外壳2、MEMS麦克风3以及振膜组件4。
所述电路板1围成收容腔10，所述电路板1的其中一侧设有贯穿其上的通孔11。比如，将所述电路板1设计呈中空的立体结构，其内部则形成所述收容腔10。本实施例中，所述电路板1包括底板12以及自底板12向靠近所述外壳2方向延伸并围设成所述收容腔10的围壁13，所述外壳2固定于所述底板12且与所述围壁13间隔。电路板1其可以是一体成型的，即为中间设置有收容腔10的电路板1；也可以是上下两层电路板共同围成成收容腔，如本实施例中的三明治结构。
所述外壳2盖设固定于所述电路板1并覆盖所述通孔11，所述外壳2与所述电路板1共同围合成谐振腔20。即所述通孔11与所述谐振腔20连通。
本实施方式中，所述外壳2包括与所述电路板1间隔相对的外壳板21和由所述外壳板21的周缘向所述电路板1方向弯折延伸并固定于所述底板12的侧板22。
所述MEMS（Microelectro Mechanical Systems）麦克风3，即微机电系统麦克风，其收容于所述收容腔10内并与所述电路板1电性连接。所述MEMS麦克风3通过电路板1以及外壳2两层壳体的屏蔽，提高了其电磁屏蔽效果，使其免受其他电子部件的干扰。所述MEMS麦克风3包括固定于所述电路板1且具有背腔30的基座31、支撑于所述基座31远离所述通孔11一端的第一振膜32和背极板33。
所述第一振膜32与所述背极板33间隔形成电容结构，通过改变所述第一振膜32与所述背极板33的间距以改变所述MEMS麦克风3产生的电容大小，从而实现电信号的变化。
所述基座31环绕所述通孔11并使所述背腔30与所述通孔11连通。
所述振膜组件4收容于所述谐振腔20内并将所述谐振腔20分隔成第一腔201和第二腔202，所述第一腔201通过所述通孔11与所述背腔30连通。
所述振动传感器100输入振动信号或压力信号时，例如，所述外壳2背离所述谐振腔20的一侧和/或所述电路板1背离所述收容腔10的一侧输入振动信号或压力信号时，所述振动组件4振动并使得所述谐振腔20内的气压产生变化。所述气压变化引起所述MEMS麦克风3的第一振膜32的振动，改变了所述第一振膜32与所述背极板33的间距，即改变了所述MEMS麦克风3产生的电容大小，从而实现将振动信号转变为电信号，并将转变的电信号传递至电路板1，从而使得所述MEMS麦克风3将外部的输入振动信号或压力信号转化为电信号，实现振动信号转化为电信号。比如，振动传感器100的电路板1和/或外壳2侧贴合于颈部，人说话时，实现骨导传递振动信号，以实现上述转化过程。
该过程中，MEMS麦克风3通过振膜组件4的振动引起的内部气压变化检测外部的输入振动信号，从而使得MEMS麦克风3最大程度的保证准确检测至气压的变化，特别是对大于1KHz的高频振动同样具有准确响应，有效提高了所述振动传感器100的灵敏度和可靠性。
因MEMS麦克风3在不同温度情况下的性能均较稳定，其灵敏度基本不会受温度、振动、温度和时间等因素影响，可靠性好，稳定性高。因MEMS麦克风3可受260℃的高温回流焊且性能不受影响，因此，组装后省去音频调试工序仍可实现准确度高的基本性能。
更优的，为了进一步改善所述振动传感器100的灵敏度，本实施方式中，所述振动传感器还包括ASIC（Application Specific Integrated Circuit）芯片5，所述ASIC芯片5收容于所述收容腔10内并与所述MEMS麦克风3电性连接。所述ASIC芯片5为所述MEMS麦克风3提供外部偏置，有效的偏置将使所述MEMS麦克风3在整个工作温度范围内都可保持稳定的声学灵敏度和电气参数，还可支持不同敏感性的麦克风结构设计，设计更灵活可靠。
本实施方式中，所述外壳2设有贯穿其上的第一泄压孔23，具体的，所述第一泄压孔23贯穿所述外壳板21设置， 整机SMT（即表面组装技术）装配时，该第一泄压孔23的设置起到平衡气压的作用。具体为，所述外壳板21通过表面组装技术贴设固定于移动设备的内部，并堵住所述第一泄压孔23实现谐振腔20的密封，有效避免了外界气导声信号干扰，进而提高了振动传感器100骨导灵敏度和频率特性。当然，所述第一泄压孔23的位置和数量不限于此，其原理都一样。
同理，所述振膜组件4设有贯穿其上的第二泄压孔40，所述第一腔201通过所述第二泄压孔40和所述第二腔202连通，用以平衡所述第二腔202与所述第一腔201的气压平衡，也即平衡所述第二腔202与背腔30的气压平衡。
具体的，所述振膜组件4包括固定于所述电路板1并环绕所述通孔11设置的垫片41以及固定于所述垫片41远离所述通孔11一侧的第二振膜42。所述垫片41、所述第二振膜42及所述电路板1共同围成所述第一腔201。即所述垫片41用于将第二振膜42与所述电路板1间隔以提供振动空间。当然，垫片41也可与第二振膜42为一体结构。所述第二泄压孔40贯穿所述第二振膜42设置，当然，所述第二泄压孔40的位置不限于此，其原理都一样。本实施方式中，所述振膜组件4还包括与所述第二振膜42固定连接的质量块43。所述质量块43贴设于所述第二振膜42靠近所述第一腔201的一侧和/或所述第二振膜42靠近所述第二腔202的一侧。
所述振膜组件4收容于由外壳2和电路板1围成的谐振腔20内，其屏蔽效果更好，同时用于发生气压变化的腔体体积变大，振动效果更好。
如图3所示，所述质量块43贴设于所述第二振膜42靠近所述第二腔202的一侧。质量块43、第二振膜42以及垫片41均位于电路板1的谐振腔20内，节省空间，便于生产。
更优的，所述第一振膜32沿其振动方向向所述电路板1上的正投影面积小于所述第二振膜42沿其振动方向向所述电路板1上的正投影面积。该结构设计第二振膜42与谐振腔20内气体接触面积更大，使其更好的振动气体，第一振膜32面积相对较小，使得MEMS麦克风3会对由安装在同一PCB上的扬声器引起的PCB噪声产生更低的振动耦合，声学性能更好，方便使用。
请结合图4所示，为图1中实施方式的振动传感器的质量块与第二振膜固定方式的第二实施方式结构示意图。该实施方式的振动传感器200其区别点在于：所述质量块243贴设于所述第二振膜242靠近所述第一腔2101的一侧。该实施方式的改变减少质量块243对第二腔2102体积的占用，增大了第二腔2102的体积，进一步提高了振动传感器200的灵敏度。除此之外，其与上述图1所示实施方式基础相同，在此不再赘述。
请结合图5所示，为图1中振动传感器的质量块与第二振膜固定方式的第三实施方式结构示意图。该实施方式的振动传感器300其区别点在于：所述质量块343贴设于所述第二振膜342靠近所述第一腔3101的一侧和所述第二振膜342靠近所述第二腔3102的一侧。即质量块343包括两组，分别贴设于第二振膜342的相对两侧。该结构设计进一步增加了振动组件34的惯性量，从而进一步提高灵敏度。除此之外，其与上述图1所示实施方式基础相同，在此不再赘述。
请结合图6，为图3中质量块结构变化后的另一实施方式结构示意图。该实施方式的振动传感器400中，位于所述第二振膜442同一侧的所述质量块443包括多个相互间隔设置质量块单元4431。该结构设计同样为增加振膜组件44的惯性量，振膜组件44更易于振动，以进一步提高灵敏度。除此之外，其与上述图3所示实施方式基础相同，在此不再赘述。
请结合图7，为本实用新型振动传感器中质量块与振膜固定方式的第四实施方式结构示意图。其与本实用新型的其它实施方式相比，主要区别在于，所述质量块543由所述第二振膜542包裹以形成固定。
具体的，所述第二振膜542包括固定于所述垫片541并相互叠设的两个第二子振膜5421，所述质量块543夹设包裹于两个所述第二子振膜5421之间。该结构设计增加了质量块543的固定强度，进一步提高了可靠性。
与相关技术相比，本实用新型的振动传感器中，通过所述电路板围成收容腔，并在所述电路板的一侧设通孔，在收容腔内设置MEMS麦克风；通过设置所述外壳与所述电路板共同围成谐振腔，外壳设有贯穿其上的第一泄压孔，谐振腔内设置振膜组件以将谐振腔分隔成第一腔和第二腔，第一腔通过通孔与背腔连通；所述振膜组件设有贯穿其上的第二泄压孔，第一腔通过第二泄压孔与第二腔连通；所述MEMS麦克风包括固定于所述电路板且具有背腔的基座、支撑于基座的第一振膜和背极板；所述基座环绕所述通孔并使所述背腔与所述通孔连通；所述通孔将所述第一腔与所述背腔连通。通过上述结构设计，所述振膜组件收容于由外壳和电路板围成的谐振腔内，其屏蔽效果更好，同时用于发生气压变化的腔体体积变大，振动效果更好；而MEMS麦克风可更好的感应由振膜组件产生的振动，并将感应的振动信号转化为电信号，从而实现对谐振腔传递的高频振动和低频振动均具有更好的振动响应，有效提高了灵敏度。
以上所述的仅是本实用新型的实施方式，在此应当指出，对于本领域的普通技术人员来说，在不脱离本实用新型创造构思的前提下，还可以做出改进，但这些均属于本实用新型的保护范围。

Claims (10)

  1. 一种振动传感器，其特征在于，所述振动传感器包括：
    电路板，所述电路板围成收容腔，所述电路板的其中一侧设有贯穿其上的通孔；
    外壳，所述外壳盖设固定于所述电路板并覆盖所述通孔，所述外壳与所述电路板共同围成谐振腔，所述外壳设有贯穿其上的第一泄压孔；
    MEMS麦克风，所述MEMS麦克风收容于所述收容腔内并与所述电路板电性连接，所述MEMS麦克风包括固定于所述电路板且具有背腔的基座、支撑于所述基座远离所述通孔一端的第一振膜和背极板；所述基座环绕所述通孔并使所述背腔与所述通孔连通；所述第一振膜与所述背极板间隔形成电容结构；以及，
    振膜组件，所述振膜组件收容于所述谐振腔内并将所述谐振腔分隔成第一腔和第二腔，所述第一腔通过所述通孔与所述背腔连通；所述振膜组件设有贯穿其上的第二泄压孔，所述第一腔通过所述第二泄压孔与所述第二腔连通；
    所述振动传感器输入振动信号或压力信号时，所述振膜组件振动，并使所述谐振腔内的气压产生变化。
  2. 根据权利要求1所述的振动传感器，其特征在于，所述振动传感器还包括ASIC芯片，所述ASIC芯片收容于所述收容腔内并与所述MEMS麦克风电性连接。
  3. 根据权利要求1所述的振动传感器，其特征在于，所述电路板包括底板以及自底板向靠近所述外壳方向延伸并围设成所述收容腔的围壁，所述外壳固定于所述底板且与所述围壁间隔。
  4. 根据权利要求1所述的振动传感器，其特征在于，所述外壳包括与所述电路板间隔相对的外壳板和由所述外壳板的周缘向所述电路板方向弯折延伸并固定于所述电路板的侧板，所述第一泄压孔贯穿所述外壳板。
  5. 根据权利要求1所述的振动传感器，其特征在于，所述振膜组件包括固定于所述电路板并环绕所述通孔设置的垫片以及固定于所述垫片远离所述通孔一侧的第二振膜，所述垫片、所述第二振膜及所述电路板共同围成所述第一腔，所述第二泄压孔贯穿所述第二振膜。
  6. 根据权利要求5所述的振动传感器，其特征在于，所述振膜组件还包括与所述第二振膜固定连接的质量块；所述质量块贴设于所述第二振膜靠近所述第一腔的一侧和/或所述第二振膜靠近所述第二腔的一侧。
  7. 根据权利要求6所述的振动传感器，其特征在于，位于所述第二振膜同一侧的所述质量块包括多个相互间隔设置质量块单元。
  8. 根据权利要求5所述的振动传感器，其特征在于，所述振膜组件还包括由所述第二振膜包裹固定的质量块。
  9. 根据权利要求8所述的振动传感器，其特征在于，所述第二振膜包括固定于所述垫片并相互叠设的两个第二子振膜，所述质量块夹设包裹于两个所述第二子振膜之间。
  10. 根据权利要求5所述的振动传感器，其特征在于，所述第一振膜沿其振动方向向所述电路板上的正投影面积小于所述第二振膜沿其振动方向向所述电路板上的正投影面积。
PCT/CN2020/121276 2020-06-30 2020-10-15 振动传感器 WO2022000853A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202021264706.6 2020-06-30
CN202021264706.6U CN218679383U (zh) 2020-06-30 2020-06-30 振动传感器

Publications (1)

Publication Number Publication Date
WO2022000853A1 true WO2022000853A1 (zh) 2022-01-06

Family

ID=79317342

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/121276 WO2022000853A1 (zh) 2020-06-30 2020-10-15 振动传感器

Country Status (2)

Country Link
CN (1) CN218679383U (zh)
WO (1) WO2022000853A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115532572A (zh) * 2022-10-14 2022-12-30 浙江大学 一种多频压电微机械超声换能器及制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN208386931U (zh) * 2018-06-29 2019-01-15 歌尔股份有限公司 振动传感器和音频设备
CN110868682A (zh) * 2019-12-18 2020-03-06 青岛歌尔智能传感器有限公司 一种mems麦克风
US20200092659A1 (en) * 2017-09-15 2020-03-19 Stmicroelectronics S.R.L. Method for manufacturing a thin filtering membrane and an acoustic transducer device including the filtering membrane
CN110958519A (zh) * 2019-11-22 2020-04-03 歌尔股份有限公司 一种主动降噪声学单元及发声单体
CN111083622A (zh) * 2019-12-27 2020-04-28 钰太芯微电子科技（上海）有限公司 一种新型防射频干扰的微机电系统麦克风

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200092659A1 (en) * 2017-09-15 2020-03-19 Stmicroelectronics S.R.L. Method for manufacturing a thin filtering membrane and an acoustic transducer device including the filtering membrane
CN208386931U (zh) * 2018-06-29 2019-01-15 歌尔股份有限公司 振动传感器和音频设备
CN110958519A (zh) * 2019-11-22 2020-04-03 歌尔股份有限公司 一种主动降噪声学单元及发声单体
CN110868682A (zh) * 2019-12-18 2020-03-06 青岛歌尔智能传感器有限公司 一种mems麦克风
CN111083622A (zh) * 2019-12-27 2020-04-28 钰太芯微电子科技（上海）有限公司 一种新型防射频干扰的微机电系统麦克风

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115532572A (zh) * 2022-10-14 2022-12-30 浙江大学 一种多频压电微机械超声换能器及制备方法
CN115532572B (zh) * 2022-10-14 2024-05-07 浙江大学 一种多频压电微机械超声换能器及制备方法

Also Published As

Publication number Publication date
CN218679383U (zh) 2023-03-21

Similar Documents

Publication Publication Date Title
CN218679379U (zh) 振动传感器
CN212572961U (zh) 振动传感器及具有其的音频设备
WO2022000793A1 (zh) 振动传感器
CN108513241A (zh) 振动传感器和音频设备
CN208386931U (zh) 振动传感器和音频设备
US10399850B2 (en) Transducer with enlarged back volume
WO2022000852A1 (zh) 振动传感器
EP2587834A1 (en) Microphone unit
US20130028459A1 (en) Monolithic Silicon Microphone
CN215187377U (zh) 振动传感器
US11895452B2 (en) Bone conduction microphone
CN212110308U (zh) 振动检测结构、骨声纹传感器和电子设备
WO2022000792A1 (zh) 振动传感器
WO2022000853A1 (zh) 振动传感器
US9357313B2 (en) Microphone unit having a plurality of diaphragms and a signal processing unit
WO2023160719A1 (zh) 振动传感器、电子设备和振动检测方法
WO2022000791A1 (zh) 振动传感器
US20150139467A1 (en) Acoustic device and microphone package including the same
US20220349745A1 (en) Vibration Sensor
US11665494B2 (en) Bone conduction microphone
JP2006311106A (ja) 音響センサ
CN114786104A (zh) 一种麦克风结构和语音通讯设备
WO2022062002A1 (zh) 一种骨传导麦克风
CN114598977B (zh) 一种mems麦克风和语音通讯设备
CN219145557U (zh) 一种麦克风结构及电子设备

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20942458

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20942458

Country of ref document: EP

Kind code of ref document: A1