A vibration sensor

Abstract

This specification relates to the field of sensors, and particularly to a vibration sensor including a vibration assembly, which includes: an acoustic transducer; a vibration assembly connected to the acoustic transducer, the vibration assembly being configured to transmit an external vibration signal to the acoustic transducer to generate an electrical signal, the vibration assembly including one or more sets of diaphragms and mass blocks, the mass blocks being physically connected to the diaphragms; the vibration assembly being configured to make the sensitivity of the vibration sensor greater than the sensitivity of the acoustic transducer within one or more target frequency bands.

Description

Technical Field

[0001] This specification relates to the field of sensors, and particularly to a vibration sensor including a vibration component. Background Art

[0002] A vibration sensor is an energy conversion device that converts vibration signals into electrical signals, and its applications include being used as a microphone (such as an air-conduction microphone, a bone-conduction microphone, etc.) or a monitoring device, etc. A vibration sensor can obtain data such as the amplitude and direction of vibration and convert it into an electrical signal or other required forms for further analysis and processing.

[0003] Sensitivity is an important performance index of a vibration sensor, and how to improve the sensitivity of the vibration sensor has become a problem to be solved. Summary of the Invention

[0004] One embodiment of this specification provides a vibration sensor, including: an acoustic transducer and a vibration component connected to the acoustic transducer. The vibration component is configured to transmit an external vibration signal to the acoustic transducer to generate a sound signal. The vibration component includes one or more groups of diaphragms and mass blocks, and the mass blocks are physically connected to the diaphragms; the vibration component is configured to make the sensitivity of the vibration sensor greater than the sensitivity of the acoustic transducer within one or more target frequency bands.

[0005] In some embodiments, the one or more groups of diaphragms and mass blocks are arranged in sequence along the vibration direction of the diaphragm; the distance between adjacent diaphragms in the vibration component is not less than the maximum amplitude of the adjacent diaphragms.

[0006] In some embodiments, in the vibration direction of the diaphragm, the projection area of the mass block is located within the projection area of the diaphragm.

[0007] In some embodiments, each group of diaphragms and mass blocks in the one or more groups of diaphragms and mass blocks corresponds to one of the one or more different target frequency bands, so that the sensitivity of the vibration sensor is greater than the sensitivity of the acoustic transducer within the corresponding target frequency band.

[0008] In some embodiments, the resonance frequency of the one or more groups of diaphragms and mass blocks is less than the resonance frequency of the acoustic transducer so that the sensitivity of the vibration sensor is greater than the sensitivity of the acoustic transducer within the one or more target frequency bands.

[0009] In some embodiments, the difference between the resonance frequency of the one or more groups of diaphragms and mass blocks and the resonance frequency of the acoustic transducer is within 1 kHz to 10 kHz.

[0010] In some embodiments, the resonance frequencies of at least two sets of diaphragms and mass blocks among the multiple sets of diaphragms and mass blocks are different.

[0011] In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of the multiple sets of diaphragms and mass blocks is less than 2 kHz.

[0012] In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of the multiple sets of diaphragms and mass blocks is not greater than 1 kHz.

[0013] In some embodiments, the resonance frequencies of the one set and the multiple sets of diaphragms and mass blocks are within 1 kHz to 10 kHz.

[0014] In some embodiments, the resonance frequencies of the one set and the multiple sets of diaphragms and mass blocks are within 1 kHz to 5 kHz.

[0015] In some embodiments, the resonance frequencies of the one set and the multiple sets of diaphragms and mass blocks are related to the parameters of the diaphragm and / or the mass block, and the parameters include at least one of the modulus of the diaphragm, the volume of the cavity formed between the acoustic transducer and the diaphragm, the radius of the mass block, the height of the mass block, and the density of the mass block.

[0016] In some embodiments, the modulus of the diaphragm is within 1 GPa to 10 GPa.

[0017] In some embodiments, the radius of the mass block is within 500 μm to 3 mm.

[0018] In some embodiments, the frequency response curve of the vibration sensor under the action of the one set or the multiple sets of diaphragms and mass blocks has multiple resonance peaks.

[0019] In some embodiments, the vibration assembly further includes a support structure for supporting the one set or the multiple sets of diaphragms and mass blocks. The support structure is physically connected to the acoustic transducer, and the one set or the multiple sets of diaphragms and mass blocks are connected to the support structure.

[0020] In some embodiments, the support structure is made of an airtight material.

[0021] In some embodiments, in the direction perpendicular to the surface connected to the diaphragm and the mass block, the projection area of the mass block does not overlap with the projection area of the support structure.

[0022] In some embodiments, the mass block is concentrically arranged with the diaphragm.

[0023] In some embodiments, the diaphragm is configured to allow air to pass through.

[0024] In some embodiments, among the plurality of diaphragms, the diaphragm farthest from the acoustic transducer is configured to be air-impermeable. In some embodiments, through-holes are provided in the diaphragm.

[0025] In some embodiments, the diaphragm includes a breathable membrane.

[0026] In some embodiments, the diaphragm includes at least one of polytetrafluoroethylene, expanded polytetrafluoroethylene, polyethersulfone, polyvinylidene fluoride, polypropylene, polyethylene terephthalate, nylon, cellulose nitrate, or mixed cellulose.

[0027] In some embodiments, the vibration assembly further includes a limiting structure; the limiting structure is configured to keep the distance between adjacent diaphragms in the vibration assembly not less than the maximum amplitude of the adjacent diaphragms.

[0028] In some embodiments, the acoustic transducer is an air-conduction microphone; the resonance frequencies of the one or more target frequency bands are configured to be 1 kHz to 10 kHz lower than the resonance frequency of the air-conduction microphone.

[0029] In some embodiments, the air-conduction microphone includes a sound pickup hole, and the one or more groups of diaphragms and mass blocks are disposed in the sound pickup hole parallel to the radial cross-section of the sound pickup hole; or, disposed outside the sound pickup hole.

[0030] In some embodiments, the mass block does not contact the inner wall of the sound pickup hole.

[0031] One embodiment of the present specification provides a sound input device, which includes any one of the above vibration sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] This specification will be further described by way of exemplary embodiments, which will be described in detail through the drawings. These embodiments are not restrictive. In these embodiments, the same numbers represent the same structures, where:

[0033] Figure 1 is a modular schematic diagram of a vibration sensor according to some embodiments of this specification;

[0034] Figure 2 is a schematic structural diagram of a vibration sensor according to some embodiments of this specification;

[0035] Figure 3 is a schematic structural diagram of a vibration sensor according to some embodiments of this specification;

[0036] Figure 4 is a schematic structural diagram of a vibration assembly according to some embodiments of this specification;

[0037] Figure 5 It is a frequency response curve graph of a vibration sensor shown according to some embodiments of this specification;

[0038] Figure 6 It is a schematic structural diagram of a vibration sensor shown based on some embodiments of this specification. Detailed implementation manners

[0039] To more clearly illustrate the technical solutions of the embodiments of this specification, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some examples or embodiments of this specification. For those of ordinary skill in the art, without creative efforts, this specification can also be applied to other similar scenarios based on these drawings. It should be understood that these exemplary embodiments are only provided to enable those skilled in the relevant art to better understand and then implement the present invention, rather than limiting the scope of the present invention in any way. Unless obvious from the language context or otherwise stated, the same reference numerals in the drawings represent the same structure or operation.

[0040] As shown in this specification and the claims, unless the context clearly indicates an exceptional situation, words such as "a", "an", "one", and / or "the" are not specifically singular and may also include plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment". The relevant definitions of other terms will be given in the following description.

[0041] In some embodiments, when the vibration sensor is used as a microphone (such as an air-conduction microphone, a bone-conduction microphone, etc.), the device for converting vibration into an electrical signal includes an acoustic transducer. Usually, there is only one resonance peak for a single acoustic transducer, and the acoustic transducer only has a relatively high sensitivity near the frequency of the resonance peak. In some embodiments, in order to improve the sensitivity of the vibration sensor, by setting multiple acoustic transducers with different resonance peaks, the receiving frequency range and sensitivity are increased, but increasing the number of acoustic transducers will lead to an increase in the volume and manufacturing cost of the vibration sensor.

[0042] In view of this, this specification relates to a vibration sensor, which, through a vibration component connected to an acoustic transducer, enables the vibration sensor to have a sensitivity greater than that of the acoustic transducer within a target frequency band. The vibration sensor can be used to receive external vibration signals and convert the vibration signals into electrical signals that can reflect sound information, where the external signals can include mechanical vibration signals or acoustic signals, etc. The vibration component can include one or more groups of diaphragms and mass blocks, and the mass blocks are physically connected to the diaphragms. The vibration component is configured to make the sensitivity of the vibration sensor greater than that of the acoustic transducer within one or more target frequency bands.

[0043] As Figure 1 shown, the vibration sensor 100 can include an acoustic transducer 120 and a vibration component 130. In some embodiments, the acoustic transducer 120 is connected to the vibration component 130, and the vibration component 130 is configured to transmit an external vibration signal to the acoustic transducer to generate an electrical signal. When vibrations occur in the external environment, the vibration component 130 responds to the vibrations in the external environment and transmits the vibration signal to the acoustic transducer 120, and then the acoustic transducer 120 converts the vibration signal into an electrical signal. The vibration sensor 100 can be applied to mobile devices, wearable devices, virtual reality devices, augmented reality devices, etc., or any combination thereof. In some embodiments, the mobile device can include a smart phone, a tablet computer, a personal digital assistant (PDA), a gaming device, a navigation device, etc., or any combination thereof. In some embodiments, the wearable device can include a smart bracelet, headphones, a hearing aid, a smart helmet, a smart watch, smart clothing, a smart backpack, smart accessories, etc., or any combination thereof. In some embodiments, the virtual reality device and / or the augmented reality device can include a virtual reality helmet, virtual reality glasses, a virtual reality patch, an augmented reality helmet, augmented reality glasses, an augmented reality patch, etc., or any combination thereof. For example, the virtual reality device and / or the augmented reality device can include Google Glass, Oculus Rift, Hololens, Gear VR, etc.

[0044] As Figure 1 shown, the vibration component 130 includes a diaphragm 131 and a mass block 132, where the mass block 132 is physically connected to the diaphragm 131. The vibration component 130 is configured to make the sensitivity of the vibration sensor 100 greater than that of the acoustic transducer 120 within one or more target frequency bands.

[0045] In some embodiments, one or more groups of diaphragms 131 and mass blocks 132 are arranged in sequence along the vibration direction of the diaphragm 131; the distance between adjacent diaphragms 131 in the vibration component 130 is not less than the maximum amplitude of the adjacent diaphragms 131. In some embodiments, the diaphragm 131 is configured to allow air to pass through.

[0046] In some embodiments, each diaphragm 131 and mass block 132 in one or more groups of diaphragms 131 and mass blocks 132 corresponds to a target frequency band among one or more different target frequency bands, so that the sensitivity of the vibration sensor 100 within the corresponding target frequency band can be greater than that of the acoustic transducer 120. In some embodiments, the sensitivity of the vibration sensor 100 after adding one or more additional groups of mass blocks 132 and diaphragms 131 can be increased by 3 dB to 30 dB compared to the acoustic transducer 120 within the target frequency band. It should be noted that in some embodiments, the sensitivity of the vibration sensor 100 after adding one or more additional groups of mass blocks 132 and diaphragms 131 can also be increased by more than 30 dB compared to the acoustic transducer 120, for example, when multiple groups of mass blocks 132 and diaphragms 131 have the same resonance peak.

[0047] In some embodiments, the method for measuring the sensitivities of the vibration sensor 100 and the acoustic transducer 120 can be as follows: under the excitation of a given acceleration (such as 1 g, where g is the acceleration due to gravity), the electrical signal of the device (such as -30 dBV) is collected, and then the sensitivity is -30 dBV / g. In some embodiments, when the acoustic transducer 120 is an air-conduction microphone, when measuring the sensitivity, the aforementioned excitation source can be replaced with sound pressure, that is, the sound pressure within a specified frequency band is input as the excitation, and the electrical signal of the collection device is measured.

[0048] In some embodiments, the frequency response curve of the vibration sensor 100 under the action of one or more groups of diaphragms 131 and mass blocks 132 can have multiple resonance peaks.

[0049] In some embodiments, the resonance frequencies of one or more sets of mass blocks 132 and the diaphragm 131 are within 1 kHz to 10 kHz. In some embodiments, the resonance frequencies of one or more sets of mass blocks 132 and the diaphragm 131 are within 1 kHz to 5 kHz. In some embodiments, the resonance frequencies of at least two sets of the mass blocks 132 and the diaphragm 131 among multiple sets of mass blocks 132 and the diaphragm 131 are different. In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of multiple sets of mass blocks 132 and the diaphragm 131 is less than 2 kHz. Herein, two adjacent resonance frequencies refer to two resonance frequencies that are numerically adjacent in terms of the magnitude of the resonance frequencies. Since the sensitivity of the vibration sensor 100 corresponding to frequencies outside the resonance frequency will rapidly decrease, by controlling the resonance frequency difference, the vibration sensor 100 has a high sensitivity over a relatively wide frequency band while the sensitivity does not exhibit large fluctuations. In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of multiple sets of mass blocks 132 and the diaphragm 131 is not greater than 1.5 kHz. In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of multiple sets of mass blocks 132 and the diaphragm 131 is not greater than 1 kHz, such as 500 Hz, 700 Hz, or 800 Hz, etc. In some embodiments, the difference between two adjacent resonance frequencies among the resonance frequencies of multiple sets of mass blocks 132 and the diaphragm 131 is not greater than 500 Hz.

[0050] In some embodiments, the diaphragm 131 may include a breathable membrane. For more descriptions of the vibration assembly, reference may be made to Figures 2 - 6 the detailed description in

[0051] Figure 2 is a schematic structural diagram of a vibration sensor according to some embodiments of the present specification.

[0052] Figure 2 The vibration sensor 200 described in Figure 1 may be an implementation manner of the vibration sensor 100 in

[0053] Reference Figure 2 , in some embodiments, the air-conduction microphone includes a housing structure 210 and a sound pickup device 221. In some embodiments, the sound pickup device 221 may include transducers in the form of capacitive, piezoelectric, etc. according to the transduction principle, which is not limited in this specification.

[0054] In some embodiments, the shape of the housing structure 210 may be a cuboid, an approximate cuboid, a cylinder, a sphere, or any other shape. The housing structure 210 encloses an accommodation space, and the sound pickup device 221 is disposed within the accommodation space. In some embodiments, the sound pickup device 221 is physically connected to the housing structure 210. Specifically, the physical connection methods may include connection methods such as welding, snap connection, bonding, or integral molding, and the connection method is not limited herein. In some embodiments, the housing structure 210 may be made of a material with a certain hardness, so that the housing structure 210 can protect the sound pickup device 221 and internal components. In some embodiments, the material of the housing structure 210 may include, but is not limited to, one or more of metals, alloy materials (such as aluminum alloy, chrome molybdenum steel, scandium alloy, magnesium alloy, titanium alloy, magnesium lithium alloy, nickel alloy, etc.), glass fiber or carbon fiber, polymer materials (for example, acrylonitrile-butadiene-styrene copolymer, polyvinyl chloride, polycarbonate, polypropylene, etc.).

[0055] In some embodiments, the housing structure 210 is provided with a sound pickup hole 211 for sound pickup. In some embodiments, the vibration assembly 230 is disposed near the sound pickup hole 211 of the housing structure 210. In some embodiments, the one or more sets of diaphragms and mass blocks are disposed outside the sound pickup hole. In some embodiments, the vibration assembly 230 is physically connected to the housing structure. Specifically, the physical connection methods may include connection methods such as welding, snap connection, bonding, or integral molding, and the connection method is not limited herein. It should be noted that in some embodiments, the one or more sets of diaphragms and mass blocks of the second generation may also be disposed within the sound pickup hole parallel to the radial cross-section of the sound pickup hole. For specific details, reference may be made to the relevant descriptions hereinafter. Figure 5 Related descriptions.

[0056] In some embodiments, when the vibration sensor 200 is used for air conduction sound pickup, when the external environment generates vibrations (for example, sound waves), the one or more sets of diaphragms and the mass blocks on the diaphragms respond to the vibrations of the external environment and generate vibrations. Since the diaphragm can allow air to pass through, the vibrations generated by the diaphragm and the mass block together with the external vibration signal (for example, sound wave) can cause the sound pressure change (or air vibration) within the sound pickup hole 211, and the vibration signal is transmitted to the sound pickup device 221 through the sound pickup hole 211 and converted into an electrical signal, thereby realizing the process that the vibration signal is strengthened within one or more target frequency bands and then converted into an electrical signal. Among them, the target frequency band may be the frequency range where the resonance frequency (or resonant frequency) corresponding to the one or more sets of diaphragms and mass blocks is located. Exemplarily, when the vibration sensor 200 is used as a microphone, the range of the target frequency band may be 200 Hz to 2 kHz. Specifically, in some embodiments, if the resonance frequency of the acoustic transducer is 2 kHz, the resonance frequency of the vibration assembly 230 may be configured to 1 kHz.

[0057] In some embodiments, when the vibration sensor 200 is used for bone conduction sound pickup, a conduction housing can be provided outside the sound pickup hole 211. The acoustic transducer 220 and the conduction housing can enclose an accommodation space, and one or more groups of diaphragms and mass blocks are arranged in the accommodation space. In some embodiments, the vibration assembly (e.g., the vibrating member) can be physically connected to the housing. When vibrations occur in the external environment, the vibrations are received through the conduction housing and cause the vibration assembly to vibrate. The vibrations of the vibration assembly can cause the air in the accommodation space to vibrate, and the vibrations generated by the diaphragms and mass blocks together with the vibration signals in the accommodation space are transmitted through the sound pickup hole 211 to the sound pickup device 221 and converted into electrical signals.

[0058] As Figure 2 shown, in some embodiments, the vibration sensor 200 includes three groups of diaphragms and mass blocks. Specifically, the three groups of diaphragms and mass blocks can have different resonance frequencies, and each group of diaphragms and mass blocks can resonate under the action of vibrations of different frequencies in the external vibration signal, so that in the sound signal obtained by the vibration sensor 200, the sensitivity is greater than that of the acoustic transducer 220 in three target frequency bands with respect to the acoustic transducer 220. It should be noted that, in some embodiments, multiple groups of diaphragms and mass blocks can have the same resonance frequency to achieve a greater improvement in sensitivity within the target frequency band. Exemplarily, when the vibration sensor 200 is used to mainly detect mechanical vibrations in the range of 5 kHz to 5.5 kHz, the resonance frequencies of multiple groups of diaphragms and mass blocks can be configured to values within this detection range (such as 5.3 kHz), so that the vibration sensor 200 has higher sensitivity within the detection range compared to the case where only one group of diaphragms and mass blocks is provided. It should be noted that Figure 2 the number of groups of diaphragms and mass blocks shown in

[0059] is only for explanation and does not limit the scope of the present invention. For example, the number of groups of diaphragms and mass blocks can be one group, two groups, four groups, etc. Figure 2 shown, the third diaphragm 2313 in the figure can be configured not to allow air to pass through. By this setting method, a sealed space is formed between the third diaphragm 2313 and the acoustic transducer 220, which can better reflect vibration information. It should be noted that, in some embodiments, the diaphragm farthest from the acoustic transducer 220 can be configured to allow air to pass through. Exemplarily, when a conduction housing is provided outside the sound pickup hole 211, the conduction housing and the acoustic transducer 220 enclose an accommodation space, and the air in the accommodation space can well reflect vibration information.

[0060] Figure 3It is a schematic structural diagram of a vibration sensor shown in some embodiments of this specification.

[0061] As Figure 3 shown, in some embodiments, the vibration component 330 in the vibration sensor 300 may include a set of diaphragms 331 and a mass block 332, and is connected to the sound sensor 320 through a support structure 333. Specifically, the mass block 332 is physically connected to the diaphragm 331, and the mass block 332 is arranged outside the diaphragm 331. In some embodiments, the mass block 332 resonates simultaneously in response to the vibration of the external environment, and the resonance generated by the diaphragm 331 and the mass block 332 transmits the external vibration signal to the acoustic transducer 320, thereby enhancing the sensitivity near the resonance frequency of the vibration component 330 and realizing the process of converting the vibration signal into an electrical signal after being enhanced in the target frequency band.

[0062] In some embodiments, since there is only a set of diaphragms 331 and a mass block 332 in the vibration sensor 300, in order to make it have a better sound pickup effect, in some embodiments, the diaphragm 331 may be airtight.

[0063] In some embodiments, the resonance frequency of each set of diaphragms and the mass block is related to the parameters of the diaphragm and / or the mass block. The parameters include the modulus of the diaphragm, the volume of the cavity formed between the acoustic transducer and the diaphragm, the radius of the mass block, the height of the mass block, the density of the mass block, etc. or a combination thereof. Specifically, the mathematical relationship between the resonance frequency and the parameters can refer to the relevant description of Formula 1 in the specification.

[0064] Please continue to refer to Figure 2 , in the embodiment, the vibration component 230 may include a first diaphragm 2311, a second diaphragm 2312, and a third diaphragm 2313 arranged in sequence in the vibration direction; the mass block may include a first mass block 2321, a second mass block 2322, and a third mass block 2323 arranged in sequence in the vibration direction. The first diaphragm 2311 is connected to the first mass block 2321, the second diaphragm 2312 is connected to the second mass block 2322, and the third diaphragm 2313 is connected to the third mass block 2323. In some embodiments, the distance between any two adjacent diaphragms among the first diaphragm 2311, the second diaphragm 2312, and the third diaphragm 2313 is not less than the maximum amplitude of the two adjacent diaphragms. This setting is used to ensure that the diaphragms will not interfere with the adjacent diaphragms during vibration, thereby affecting the transmission effect of the vibration signal. In some embodiments, when the vibration component 230 includes multiple sets of diaphragms and mass blocks, the diaphragms are arranged in sequence along the direction perpendicular to the vibration direction of the diaphragms. In some embodiments, the distance between adjacent diaphragms may be the same or different. In some embodiments, the diaphragms may form multiple cavities with the gaps between the adjacent diaphragms, and the multiple cavities between the diaphragms and the adjacent diaphragms can accommodate air and allow the diaphragms to vibrate therein.

[0065] In some embodiments, the vibration assembly 230 may further include a limiting structure (not shown in the figure), which is configured to keep the distance between adjacent diaphragms in the vibration assembly not less than the maximum amplitude of the adjacent diaphragms. In some embodiments, the limiting structure may be connected to the edge of the diaphragm, and its damping is controlled so as not to interfere with the vibration of the diaphragm.

[0066] In some embodiments, the mass blocks in multiple groups of vibration assemblies 230 may include a plurality of them, and the plurality of mass blocks may be respectively disposed on both sides of the diaphragm. Exemplarily, assuming that a group of vibration assemblies includes two mass blocks, the two mass blocks are symmetrically arranged on both sides of the diaphragm. In some embodiments, the mass blocks in multiple groups of vibration assemblies 230 may be located on the same side of the diaphragm, wherein the mass blocks may be disposed on the outer side or the inner side of the diaphragm. Here, the side of the diaphragm close to the acoustic transducer 220 is the inner side, and the side away from the acoustic transducer 220 is the outer side. It should be noted that, in some embodiments, the mass blocks in multiple groups of vibration assemblies may be located on different sides of the diaphragm. For example, the first mass block 1321 and the second mass block 2322 are located on the outer side of the corresponding diaphragm, and the third mass block 2323 is located on the inner side of the corresponding diaphragm.

[0067] In some embodiments, the diaphragm is configured as a film-like structure capable of allowing air to pass through. In some embodiments, the diaphragm may be a breathable membrane. Configuring the diaphragm to allow air to pass through enables the vibration signal to cause the vibration assembly 230 to vibrate while further penetrating the breathable membrane and being received by the acoustic transducer, thereby improving the sensitivity in the target frequency band. In some embodiments, the material of the diaphragm is a material that can undergo elastic deformation within a certain range. Specifically, the diaphragm can be made of at least one of the following materials: PTFE (polytetrafluoroethylene), ePTFE (expanded polytetrafluoroethylene), PES (polyethersulfone), PVDF (polyvinylidene fluoride), PP (polypropylene), PETE (polyethylene terephthalate), nylon, NC (nitrocellulose), and MCE (mixed cellulose), etc. In some embodiments, the diaphragm and the mass block can be connected by means such as snap connection, bonding, or integral molding, and the connection method is not limited in this specification. In some embodiments, the thickness of the diaphragm can be 0.05 μm to 100 μm. Specifically, the thickness of the diaphragm is related to the material of the diaphragm. For example, when ePTFE (expanded polytetrafluoroethylene) is selected as the diaphragm material, its thickness is 0.5 μm to 100 μm, and the preferred thickness of the ePTFE film is 1 μm to 10 μm, such as 2 μm, 5 μm, 7 μm, etc. In some embodiments, preferably, the minimum air permeability of the ePTFE film can be controlled to be not less than 10 L / hr to ensure good air permeability, and at the same time, the ePTFE film provides a certain degree of waterproof performance to protect the internal components. In some embodiments, other breathable materials with a modulus of 1 GPa to 10 GPa for the diaphragm or one-tenth to one-hundredth of the modulus of the sensitive element 222 in the acoustic transducer 220 can also be selected, and no further examples are given here. The sensitive element is the device in the acoustic transducer 220 for receiving vibration signals. In some embodiments, the materials and sizes of the multiple diaphragms in the vibration assembly 230 can be different or the same. Exemplarily, the first diaphragm 2311 can be made of nylon, and the second diaphragm 2312 can be made of ePTFE material; the radius of the third diaphragm 2313 can be larger than that of the first diaphragm 2311 and the second diaphragm 2312.

[0068] In some embodiments, when the diaphragm is configured to be airtight, the material of the diaphragm can be a polymer film, such as polyurethane, epoxy resin, acrylate, etc., or a metal film, such as copper, aluminum, tin, or other alloys and their composite films, etc. In some embodiments, it can also be obtained by treating the above-mentioned breathable membrane (such as covering the air holes).

[0069] In some embodiments, the diaphragm can be a thin film material with through holes. Specifically, the aperture of the through holes is 0.01 μm to 10 μm. Preferably, the aperture of the through holes can be 0.1 μm to 5 μm, such as 0.2 μm, 0.5 μm, 0.8 μm, 1 μm, 2 μm, etc. In some embodiments, the diameters of the through holes on the multiple diaphragms in the vibration assembly 230 can be the same or different, and the diameters of the through holes on a single diaphragm can be the same or different. In some embodiments, the aperture of the through holes can also be greater than 5 μm. When the aperture of the through holes is greater than 5 μm, other materials (such as silicone rubber, etc.) can be provided on the diaphragm to cover some of the through holes or some regions of the through holes without affecting air permeability.

[0070] In some embodiments, the material of the mass block can be one or more of copper, tin, or other alloys and their composite materials. In some embodiments, the vibration sensor 200 can be applied to the design of MEMS devices. In the MEMS device process, the diaphragm can be a single-layer material along its thickness direction, such as Si, SiO2, SiNx, SiC, etc., and can be a double-layer or multi-layer composite material, such as Si / SiO2, SiO2 / Si, Si / SiNx, SiNx / Si / SiO2, etc. The counterweight block can be a single-layer material, such as Si, Cu, etc., or a double-layer or multi-layer composite material, such as Si / SiO2, SiO2 / Si, Si / SiNx, SiNx / Si / SiO2, etc.

[0071] In some embodiments, the vibration assembly 230 can further include a support structure 233. The support structure 233 is used to support one or more groups of diaphragms and mass blocks. The support structure 233 is physically connected to the acoustic transducer 220 (for example, the housing structure 210), and one or more groups of diaphragms and mass blocks are connected to the support structure 233. Specifically, the support structure 233 is physically connected to the housing structure 210, and the physical connection method can include snap connection, bonding, or integral molding and other connection methods. In some embodiments, preferably, the support structure 233 is connected to the housing structure 210 by bonding, and the bonding materials can include but are not limited to epoxy glue and silicone rubber, etc.

[0072] In some embodiments, the support structure can also be connected to the support structure 233 to achieve fixed support to control the distance between adjacent diaphragms to ensure the transmission effect of vibration signals.

[0073] Figure 4 is a schematic structural diagram of a vibration assembly shown in some embodiments of this specification.

[0074] Refer simultaneously to Figure 2 and Figure 4, in some embodiments, one or more sets of diaphragms and mass blocks in the vibration assembly are located within the space enclosed by the support structure 233 and are physically connected to the support structure 233. Specifically, the physical connection method here can be bonding, clamping, etc. Preferably, bonding connection can be used, and the bonding material can include but is not limited to epoxy glue, silicone glue, etc. In some embodiments, the support structure 233 can have a hollow tubular structure with openings at both ends, and the cross-section of the tubular structure can be rectangular, triangular, circular, or other shapes. In some embodiments, the cross-sectional area of the tubular structure can be the same everywhere, or not completely the same. For example, the end closer to the acoustic transducer 220 has a larger cross-sectional area. In some embodiments, one set of diaphragms and mass blocks in the vibration assembly 230 can be installed at the opening of the support structure 233.

[0075] In some embodiments, the diaphragm can be embedded on the inner wall of the support structure 233 or embedded within the support structure 233. In some embodiments, the diaphragm can vibrate within the space inside the support structure 233 while completely blocking the opening of the support structure, that is, the area of the diaphragm can be greater than or equal to the area of the opening of the support structure. This setting enables the air vibration in the external environment (e.g., sound waves) to pass through the diaphragm as completely as possible, and then the sound pickup device 221 can pick up this vibration, effectively improving the sound pickup quality.

[0076] In some embodiments, the support structure 233 is made of airtight material. The airtight support structure 233 can cause the vibration signal in the air to change the sound pressure (or air vibration) inside the support structure 233 during the transmission process, so that the internal vibration signal of the support structure 233 is transmitted to the acoustic transducer 220 through the sound pickup hole 211 and will not escape outward through the support structure 233 during the transmission process, thereby ensuring the sound pressure intensity and improving the sound transmission effect. In some embodiments, the support structure 233 can include but is not limited to one or more of metals, alloy materials (such as aluminum alloy, chromium molybdenum steel, scandium alloy, magnesium alloy, titanium alloy, magnesium lithium alloy, nickel alloy, etc.), rigid plastics, foams, etc.

[0077] Reference Figure 4 , in some embodiments, in the vibration direction of the diaphragm, the projection area of the mass block is located within the projection area of the diaphragm, that is, in the direction parallel to the surface connected to the diaphragm and the mass block (i.e., perpendicular to the vibration direction), the cross-sectional area of the mass block is smaller than the cross-sectional area of the diaphragm. Combining Figure 2 , for example, the first mass block 2321 is located within the projection area of the first diaphragm 2311; the second mass block 2322 is located within the projection area of the second diaphragm 2312, and the third mass block 2323 is located within the projection area of the third diaphragm 2313. By ensuring that the cross-sectional dimension of the mass block is smaller than that of the diaphragm, the mass block will not interfere with the vibration of the diaphragm.

[0078] In some embodiments, in the direction perpendicular to the surface connected to the diaphragm and the mass block (i.e., perpendicular to the vibration direction), the projection area of the mass block does not overlap with the projection area of the support structure. This setting is to avoid the vibration of the diaphragm and the mass block being restricted by the support structure 233.

[0079] In some embodiments, the shape of the diaphragm may include a circle, a rectangle, a triangle, or an irregular shape, etc. In some embodiments, the shape of the diaphragm may also be set according to the shape of the support structure or the conduit, which is not limited in this specification. In some embodiments, the shape of the mass block may be a cylinder, a frustum of a cone, a cone, a cube, a triangular prism, etc. Its size and material will be described later, and the shape is not limited in this specification.

[0080] In some embodiments, when the mass block or the diaphragm has a circular outer contour, the mass block may be concentrically arranged with the diaphragm. When the concentrically arranged mass block vibrates, the kinetic energy is more evenly dispersed on the diaphragm, so that the diaphragm can better respond to the vibration. In some other embodiments, the mass block may also be arranged at other positions of the diaphragm, such as an eccentric position. The eccentric position means that the mass block is not concentrically arranged with the diaphragm. Preferably, the eccentric distance between the mass block and the diaphragm may not exceed 50 μm. In some embodiments, the resonance frequency of one or more groups of diaphragms and mass blocks is less than the resonance frequency of the acoustic transducer so that the sensitivity of the vibration sensor is greater than that of the acoustic transducer in one or more target frequency bands. In some embodiments, the relationship between the resonance frequency and sensitivity of the diaphragm and the mass block and the acoustic transducer can be referred to Figure 5 in the frequency response curve graph of the vibration sensor in

[0081] Specifically, in some embodiments, multiple groups of mass blocks and diaphragms may be configured to have a resonance frequency 1 kHz to 10 kHz lower than the resonance frequency of the acoustic transducer, such as 2 kHz, 3 kHz, 5 kHz, or 7.5 kHz, etc., so as to improve the overall sensitivity of the vibration sensor. In some embodiments, when the acoustic transducer is the air-conduction microphone in the foregoing example, multiple groups of mass blocks and diaphragms are configured to make the sensitivity of the vibration sensor greater than that of the acoustic transducer in one or more target frequency bands, wherein the resonance frequency of one or more target frequency bands is configured to be 1 kHz to 10 kHz lower than the resonance frequency of the air-conduction microphone. Specifically, it may be 1.5 kHz, 2 kHz, 3 kHz, or 5 kHz, etc.

[0082] Figure 5 is the frequency response curve graph of the vibration sensor shown in some embodiments of this specification.

[0083] Such as Figure 5As shown, in some embodiments, the frequency response curve of the vibration sensor under the action of the one or more sets of diaphragms and mass blocks has multiple resonance peaks. In the figure, , and correspond to the resonance peaks of the multiple sets of mass blocks and diaphragms added respectively, being the resonance peak of the acoustic transducer. In some embodiments, each set of diaphragms and mass blocks in the one or more sets of diaphragms and mass blocks corresponds to one of the one or more different target frequency bands, so that the sensitivity of the vibration sensor within the corresponding target frequency band is greater than the sensitivity of the acoustic transducer. In the figure, the solid line is the frequency response curve 500 of the vibration sensor after adding multiple sets of mass blocks and diaphragms. After adding one or more sets of diaphragms and mass blocks with resonance frequencies less than that of the acoustic transducer, the vibration sensor correspondingly increases one or more resonance peaks.

[0084] It can be seen from the figure that the frequency response curve 500 of the vibration sensor has 4 resonance peaks, and at the same time, its sensitivity is at least increased by compared with that of the acoustic transducer. At the same time, from the frequency response curve of the acoustic transducer (i.e., the curve where the resonance peak is located), it can be seen that the vibration sensor has higher sensitivity within the frequency band of ~ . It can be seen that the diaphragms and mass blocks increase the width of the frequency band with higher sensitivity of the vibration sensor, enabling it to receive vibration signals within a larger frequency range, increasing the receiving frequency range and sensitivity of the vibration sensor. Compared with the method of increasing the receiving frequency range by adding multiple sets of acoustic transducers with different resonance peaks, the overall volume of the device is reduced, the cost is reduced, and it has stronger performance on the basis of higher integration.

[0085] Exemplarily, taking the 3 sets of diaphragms and mass blocks in Figure 4 as an example, the resonance peaks , and of the 3 sets of diaphragms may have resonance frequencies of 1.5 kHz, 2 kHz, and 2.5 kHz respectively. In some embodiments, through this setting method, the vibration sensor can obtain better sound pickup ability. In particular, it can better acquire the sound information within the frequency band corresponding to the voice.

[0086] In some embodiments, the resonance frequencies of the one or more sets of diaphragms and mass blocks are related to the parameters of the diaphragms and / or mass blocks. The parameters include at least one of the modulus of the diaphragm, the volume of the cavity formed between the acoustic transducer and the diaphragm, the radius of the mass block, the height of the mass block, and the density of the mass block. In some embodiments, the relationship between the resonance frequencies of the multiple sets of diaphragms and mass blocks and the sensitivity can be expressed as:

[0087] (1)

[0088] in, S To set the sensitivity of the vibration sensor behind the vibration assembly, f is the resonant frequency of the vibrating component, K film is the diaphragm stiffness, K foam is the supporting structure stiffness, V cavity is the cavity volume, R m is the mass radius, h m is the mass block height, r m is the mass density. Cavity volume V cavity The sensitive element 222 on the pickup device 221 and the diaphragm in the closest vibration component 230 (such as Figure 2 The spatial volume formed between the first diaphragm 2311).

[0089] Specifically, in some embodiments, the sensitivity S With diaphragm stiffness K film Increases and decreases with the stiffness of the supporting structure K foam Increases and decreases with the cavity volume V cavity The increase of the mass block first increases and then decreases, R m Increase first and then decrease, with the height of the mass block h m Increases with mass density r m Increase and improve. The resonant frequency of the vibration component f With diaphragm stiffness K film Increases with the increase of the supporting structure stiffness K foam Increases with the mass radius R m The increase of the mass block first decreases and then increases, h m Increases and decreases with mass density r m In some embodiments, the sensitivity and resonant frequency can be adjusted by controlling the stiffness of the diaphragm, the volume of the cavity, and the material and size of the mass.

[0090] Figure 6It is a schematic structural diagram of a vibration sensor shown based on some embodiments in this specification.

[0091] In some embodiments, one or more groups of diaphragms and mass blocks in the vibration sensor 600 can be disposed in the sound pickup hole parallel to the radial cross-section of the sound pickup hole (i.e., perpendicular to the vibration direction). As Figure 6 shown, in some embodiments, a conduit 611 can be provided at the sound pickup hole. The diaphragm and the mass block include a first diaphragm 6311, a second diaphragm 6312 disposed in the sound pickup hole parallel to the radial cross-section of the sound pickup hole, and a first mass block 6321 and a second mass block 6322. In some embodiments, the conduit 611 can be made of an airtight material, and its function is similar to that of the support structure 233 in the foregoing vibration sensor 200. When calculating the sensitivity and the resonance frequency of the vibration assembly, the stiffness of the support structure K foam can be taken as the stiffness of the material of the conduit 611. In some embodiments, to ensure the free vibration of the mass block, the mass block does not contact the inner wall of the sound pickup hole or the conduit 611. It should be noted that the setting of the conduit 611 is only a specific embodiment and does not limit the scope of the present invention. For example, in some embodiments, the conduit 611 can also be not provided, and one or more groups of diaphragms and mass blocks are directly connected to the sound pickup hole, or the support structure is disposed in the sound pickup hole and supports one or more groups of diaphragms and mass blocks.

[0092] In some embodiments, the first mass block 6321 and the second mass block 6322 can resonate simultaneously in response to the vibration of the external environment. The resonance generated by the first diaphragm 6311, the second diaphragm 6312, and the first mass block 6321 and the second mass block 6322 and the external vibration signal are transmitted to the acoustic sensor 620 through the conduit 611 and converted into an electrical signal, thereby realizing the process that the vibration signal is strengthened in one or more target frequency bands and then converted into an electrical signal. It should be noted that Figure 6 the number of groups of the diaphragms and mass blocks shown as two groups is only for illustration and does not limit the protection scope of the present invention. For example, the number of groups of the diaphragms and mass blocks can be one group, three groups, or others.

[0093] In some embodiments of this specification, a sound input device is further provided, which includes the vibration sensor in the foregoing embodiments, and picks up sound through the vibration sensor and converts it into an electrical signal for further processing.

[0094] The basic concepts have been described above. Obviously, for those skilled in the art, the above invention disclosure is only an example and does not constitute a limitation to this specification. Although not explicitly stated here, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this specification.

[0095] At the same time, this specification uses specific terms to describe the embodiments of this specification. Such as "one embodiment", "an embodiment" and / or "some embodiments" mean a certain feature, structure or characteristic related to at least one embodiment of this specification. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of this specification can be appropriately combined.

[0096] In addition, those skilled in the art can understand that various aspects of this specification can be illustrated and described by several patentable types or situations, including any new and useful processes, machines, products or combinations of substances or any new and useful improvements to them. Accordingly, various aspects of this specification can be executed entirely by hardware, can be executed entirely by software (including firmware, resident software, microcode, etc.), or can be executed by a combination of hardware and software. The above hardware or software can all be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". In addition, various aspects of this specification may be embodied as a computer product located in one or more computer-readable media, and this product includes computer-readable program codes.

[0097] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences, the use of numerical letters, or the use of other names in this specification are not used to limit the order of the processes and methods in this specification. Although some currently considered useful invention embodiments are discussed through various examples in the above disclosure, it should be understood that such details only serve the purpose of illustration. The appended claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that conform to the essence and scope of the embodiments of this specification. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only through software solutions, such as installing the described system on existing servers or mobile devices.

[0098] Similarly, it should be noted that, in order to simplify the presentation disclosed in this specification and thus assist in the understanding of one or more embodiments of the invention, in the foregoing description of the embodiments of this specification, multiple features are sometimes grouped into one embodiment, drawing, or description thereof. However, this method of disclosure does not mean that the features required by the subject matter of this specification are more than those mentioned in the claims. In fact, the features of the embodiments are fewer than all the features of the individual embodiments disclosed above.

[0099] In some embodiments, numbers are used to describe components and the quantity of attributes. It should be understood that such numbers used for the description of embodiments are modified by the modifiers "about", "approximate", or "substantially" in some examples. Unless otherwise specified, "about", "approximate", or "substantially" indicate that the said numbers allow a variation of ±20%. Accordingly, in some embodiments, the numerical data used in the specification and claims are approximate values, and such approximate values may vary according to the characteristics required by individual embodiments. In some embodiments, the numerical data should consider the specified significant digits and adopt the method of retaining the general number of digits. Although the numerical ranges and data used in some embodiments of this specification to confirm the breadth of their scope are approximate values, in specific embodiments, such numerical settings are as precise as possible within the feasible range.

[0100] Finally, it should be understood that the embodiments described in this specification are only used to illustrate the principles of the embodiments of this specification. Other variations may also fall within the scope of this specification. Therefore, by way of example and not limitation, alternative configurations of the embodiments of this specification may be regarded as consistent with the teachings of this specification. Accordingly, the embodiments of this specification are not limited to the embodiments explicitly introduced and described in this specification.

Claims

1. A vibration sensor, comprising: An acoustic transducer; A vibration assembly connected to the acoustic transducer, the vibration assembly being configured to transmit an external vibration signal to the acoustic transducer to generate an electrical signal, the vibration assembly including one or more sets of diaphragms and mass blocks, the mass blocks being physically connected to the diaphragms; the vibration sensor being configured such that the frequency response curve under the action of the one or more sets of diaphragms and mass blocks has multiple resonance peaks; The vibration assembly is configured to make the sensitivity of the vibration sensor greater than the sensitivity of the acoustic transducer within one or more target frequency bands, wherein each set of diaphragms and mass blocks in the one or more sets of diaphragms and mass blocks corresponds to one of the one or more target frequency bands, such that the sensitivity of the vibration sensor is greater than the sensitivity of the acoustic transducer within the corresponding target frequency band.

2. The vibration sensor according to claim 1, wherein The multiple sets of diaphragms and mass blocks are arranged in sequence along the vibration direction of the diaphragms; the distance between adjacent diaphragms in the vibration assembly is not less than the maximum amplitude of the adjacent diaphragms.

3. The vibration sensor according to claim 1, wherein, The diaphragm is configured to allow air to pass through.

4. The vibration sensor according to claim 1, wherein, The resonance frequency of the one or more sets of diaphragms and mass blocks is less than the resonance frequency of the acoustic transducer so that the sensitivity of the vibration sensor is greater than the sensitivity of the acoustic transducer within the one or more target frequency bands; wherein, the difference between the resonance frequency of the one or more sets of diaphragms and mass blocks and the resonance frequency of the acoustic transducer is within 1 kHz to 10 kHz.

5. The vibration sensor according to claim 1, wherein, The resonance frequencies of at least two sets of diaphragms and mass blocks in the multiple sets of diaphragms and mass blocks are different; the difference between adjacent two resonance frequencies among the resonance frequencies of the multiple sets of diaphragms and mass blocks is not greater than 1 kHz.

6. The vibration sensor according to claim 1, wherein, The resonance frequency of the one or more sets of diaphragms and mass blocks is related to the parameters of the diaphragm and / or the mass block, the parameters including at least one of the modulus of the diaphragm, the volume of the cavity formed between the acoustic transducer and the diaphragm, the radius of the mass block, the height of the mass block, and the density of the mass block.

7. The vibration sensor according to claim 1, wherein, The vibration assembly further includes a support structure for supporting the one or more sets of diaphragms and mass blocks, the support structure being physically connected to the acoustic transducer, and the one or more sets of diaphragms and mass blocks being connected to the support structure; The support structure is made of an airtight material.

8. The vibration sensor according to claim 1, wherein, The acoustic transducer is an air-conduction microphone; the air-conduction microphone includes a sound pickup hole, and the one or more sets of diaphragms and mass blocks are arranged in the sound pickup hole parallel to the radial cross-section of the sound pickup hole; or, arranged outside the sound pickup hole; The resonance frequency of the one or more target frequency bands is configured to be 1 kHz to 10 kHz lower than the resonance frequency of the air-conduction microphone.

9. A sound input device, comprising the vibration sensor according to any one of claims 1 to 8 above.

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