A vibration sensor

Abstract

One or more embodiments of the present specification relate to a vibration sensor, comprising: a vibration receiver, comprising a shell and a vibration unit, the shell forming an acoustic cavity, the vibration unit being located in the acoustic cavity and dividing the acoustic cavity into a first acoustic cavity and a second acoustic cavity; and an acoustic transducer, acoustically connected to the first acoustic cavity, wherein: the shell is configured to generate vibrations based on an external vibration signal, the vibration unit vibrates in response to the vibration of the shell, and transmits the vibrations to the acoustic transducer through the first acoustic cavity to generate an electrical signal, the vibration unit comprises a mass element and an elastic element, and the deviation between the cross-sectional areas of the mass element and the first acoustic cavity perpendicular to the vibration direction of the mass unit is less than 25%.

Description

[0001] Cross-references

[0002] This application claims priority to the international application with application number PCT / CN2020 / 140180 filed on December 28, 2020 and the Chinese application with application number 202110445739.3 filed on April 23, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of acoustics, and in particular to a vibration sensor. Background Art

[0004] A vibration sensor is an energy conversion device that converts a vibration signal into an electrical signal. When the vibration sensor is used as a bone conduction microphone, the vibration sensor can detect the vibration signal transmitted through the skin when a person speaks, and convert the vibration signal transmitted by the human skin into an electrical signal, thereby achieving the effect of transmitting sound. The sensitivity of the vibration sensor will affect the quality of the sound it transmits. Current vibration sensors usually include a mass element and an elastic element. The elastic element needs to support the mass element and provide suitable damping (i.e., spring coefficient) for the vibration of the mass element. In order to improve the sensitivity of the vibration sensor, it is necessary to minimize the spring coefficient of the elastic element. However, in order to provide sufficient elastic force for the mass element, the spring coefficient of the elastic element is difficult to be set small enough, which leads to the generally low sensitivity of the vibration sensor. Therefore, it is desired to provide a vibration sensor that can provide sufficient elastic force and has improved sensitivity. Summary of the invention

[0005] In order to solve the problem of low sensitivity of the above-mentioned vibration sensor, the technical solution of this specification is implemented as follows:

[0006] On the one hand, the present specification provides a vibration sensor, comprising: a vibration receiver, comprising a shell and a vibration unit, the shell forming an acoustic cavity, the vibration unit being located in the acoustic cavity and dividing the acoustic cavity into a first acoustic cavity and a second acoustic cavity; and an acoustic transducer, acoustically connected to the first acoustic cavity, wherein: the shell is configured to generate vibrations based on an external vibration signal, the vibration unit vibrates in response to the vibration of the shell, and transmits the vibrations to the acoustic transducer through the first acoustic cavity to generate an electrical signal, the vibration unit comprises a mass element and an elastic element, and the deviation between the cross-sectional areas of the mass element and the first acoustic cavity perpendicular to the vibration direction of the mass element is less than 25%.

[0007] In some embodiments, within a frequency range less than 1000 Hz, the sensitivity of the vibration sensor is greater than or equal to -40 dB.

[0008] In some embodiments, the elastic element is connected to a side wall of the mass element in a surrounding manner, and the elastic element extends toward the acoustic transducer and is directly or indirectly connected to the acoustic transducer.

[0009] In some embodiments, the width of the elastic element varies from one side close to the mass element to another side far from the mass element, and the variation is less than or equal to 300 um.

[0010] In some embodiments, the shell is connected to the acoustic transducer, and one end of the elastic element extending toward the acoustic transducer is directly connected to the acoustic transducer.

[0011] In some embodiments, the vibration receiver further includes a substrate, wherein the substrate is disposed on the acoustic transducer, and one end of the elastic element extending toward the acoustic transducer is connected to the substrate.

[0012] In some embodiments, the substrate includes a bottom plate and a side wall, the bottom plate is connected to the acoustic transducer, and the inner surface of the side wall is connected to the elastic element.

[0013] In some embodiments, the elastic element includes a first elastic portion and a second elastic portion, wherein two ends of the first elastic portion are respectively connected to the side wall of the mass element and the second elastic portion, and the second elastic portion extends toward the acoustic transducer and is directly or indirectly connected to the acoustic transducer.

[0014] In some embodiments, a surface of the elastic element remote from the acoustic transducer is lower than a surface of the mass element remote from the acoustic transducer.

[0015] In some embodiments, a volume of the first acoustic cavity is smaller than a volume of the second acoustic cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present application will be further described in the form of exemplary embodiments, which will be described in detail by way of the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:

[0017] Figure 1 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0018] Figure 2 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0019] Figure 3 is a schematic diagram of a connection method of a mass element and an elastic element according to some embodiments of the present application;

[0020] Figure 4A is a schematic diagram of a vibration unit according to some embodiments of the present application;

[0021] Figure 4B is a schematic diagram of a vibration unit according to some other embodiments of the present application;

[0022] Figure 4C is a schematic diagram of a vibration unit according to some other embodiments of the present application;

[0023] Figure 5 is a schematic diagram of a vibration receiver according to some embodiments of the present application;

[0024] Figure 6 is a simplified structural schematic diagram of a vibration system according to some embodiments of the present application;

[0025] Figure 7 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0026] Figure 8 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0027] Fig. 9 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0028] Fig.10 is a frequency response curve diagram of a vibration sensor according to some embodiments of the present application;

[0029] Fig.11 is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application;

[0030] Fig.12 It is a schematic diagram of the structure of a vibration sensor according to some embodiments of the present application. DETAILED DESCRIPTION

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0032] It should be understood that the "system", "device", "unit" and / or "module" used herein are a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0033] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "comprises" and "includes" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0034] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, the various steps may be processed in reverse order or simultaneously. At the same time, other operations may also be added to these processes, or one or more operations may be removed from these processes.

[0035] A vibration sensor is provided in an embodiment of the present specification. The vibration sensor may include a vibration receiver and an acoustic transducer. The vibration receiver may include a shell and a vibration unit. The shell may form an acoustic cavity. The vibration unit may be located in the acoustic cavity and separate the acoustic cavity into a first acoustic cavity and a second acoustic cavity. The acoustic transducer may be acoustically connected to the first acoustic cavity. The shell may be configured to generate vibrations based on an external vibration signal (for example, a signal generated by vibrations of bones, skin, etc. when a user speaks). The vibration unit may vibrate in response to the vibration of the shell, and transmit the vibration to the acoustic transducer through the first acoustic cavity to generate an electrical signal. The vibration unit may include a mass element and an elastic element. The deviation between the cross-sectional area of ​​the mass element and the first acoustic cavity perpendicular to the vibration direction of the mass element is less than 25%, which improves the air volume compression ratio in the first acoustic cavity during the vibration of the vibration unit, thereby improving the sensitivity of the vibration sensor.

[0036] In some embodiments, the elastic element may be connected to the side wall of the mass element and extend toward the acoustic transducer to directly or indirectly connect to the acoustic transducer, so that the elastic element undergoes shear deformation during the vibration of the vibration unit. Compared with tensile and compressive deformation, shear deformation reduces the spring constant of the elastic element, which reduces the resonant frequency of the vibration sensor, thereby increasing the vibration amplitude of the mass element during the vibration of the vibration unit and improving the sensitivity of the vibration sensor.

[0037] Figure 1 1 is a schematic diagram of the structure of a vibration sensor 100 according to some embodiments of this specification. Figure 1As shown, the vibration sensor 100 may include a vibration receiver 110 and an acoustic transducer 120. In some embodiments, the vibration receiver 110 and the acoustic transducer 120 may be physically connected. The physical connection in this specification may include welding, clamping, gluing, or integral molding, or any combination thereof.

[0038] In some embodiments, the vibration sensor 100 can be used as a bone conduction microphone. When used as a bone conduction microphone, the vibration sensor 100 can receive the vibration signal of the bone, skin and other tissues generated when the user speaks, and convert the vibration signal into an electrical signal containing sound information. Since the sound (or vibration) in the air is hardly collected, the vibration sensor 100 can be free from the influence of the surrounding environmental noise (for example, the sound of other people talking around, the noise generated by the passing of vehicles) to a certain extent, and is suitable for use in a noisy environment to collect the voice signal when the user speaks. As an example only, the noisy environment may include noisy restaurants, meeting places, streets, near roads, fire scenes and other occasions. In some embodiments, the vibration sensor 100 can be applied to headphones (for example, air conduction headphones and bone conduction headphones), hearing aids, hearing aids, glasses, helmets, augmented reality (AR) devices, virtual reality (VR) devices, etc. or any combination thereof. For example, the vibration sensor 100 can be applied to headphones as a bone conduction microphone.

[0039] The vibration receiver 110 may be configured to receive and transmit a vibration signal. In some embodiments, the vibration receiver 110 includes a housing and a vibration unit. The housing may be a hollow structure, and some components of the vibration sensor 100 (e.g., the vibration unit) may be located in the housing. For example, the housing may form an acoustic cavity, and the vibration unit may be located in the acoustic cavity. In some embodiments, the shape of the housing may be a three-dimensional structure of regular or irregular shapes such as a cuboid, a cylinder, a truncated cone, etc. In some embodiments, the material of the housing may include metal (e.g., copper, stainless steel), an alloy, plastic, etc., or any combination thereof. In some embodiments, the housing may have a certain thickness to ensure sufficient strength, so as to better protect the components of the vibration sensor 100 (e.g., the vibration unit) disposed in the housing. In some embodiments, the vibration unit may separate the acoustic cavity formed by the housing into a first acoustic cavity and a second acoustic cavity. The first acoustic cavity may be acoustically connected to the acoustic transducer 120. Acoustic communication may be a communication method capable of transmitting sound pressure, sound waves, or vibration signals.

[0040] The acoustic transducer 120 can receive a vibration signal and convert the received vibration signal into an electrical signal containing sound information. In some embodiments, the vibration signal can be received and transmitted to the first acoustic cavity via the vibration receiver 110, and the first acoustic cavity can transmit the vibration signal to the acoustic transducer 120 through acoustic communication. In some embodiments, when the vibration sensor 100 is working, the shell can vibrate based on an external vibration signal (for example, a signal generated by the vibration of bones, skin, etc. when the user speaks). The vibration unit can vibrate in response to the vibration of the shell, and transmit the vibration to the acoustic transducer 120 through the first acoustic cavity. For example, the vibration of the vibration unit can cause a volume change of the first acoustic cavity, thereby causing a change in the air pressure in the first acoustic cavity, and converting the change in the air pressure in the cavity into a change in the sound pressure in the cavity. The acoustic transducer 120 can detect the change in the sound pressure of the first acoustic cavity and generate an electrical signal based on this. For example, the acoustic transducer 120 may include a diaphragm. The sound pressure in the first acoustic cavity changes and acts on the diaphragm, causing the diaphragm to vibrate (or deform). The acoustic transducer 120 converts the vibration of the diaphragm into an electrical signal. Figure 2-12 Detailed description.

[0041] It should be noted that the above description of the vibration sensor 100 and its components is only for example and illustration, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor 100 under the guidance of this specification. In some embodiments, the vibration sensor 100 may also include other components, such as a power supply, to provide electrical energy to the acoustic transducer 120, etc. These modifications and changes are still within the scope of this specification.

[0042] Figure 2 2 is a schematic diagram of the structure of a vibration sensor 200 according to some embodiments of this specification. Figure 2 As shown, the vibration sensor 200 may include a vibration receiver 210 and an acoustic transducer 220. The vibration receiver 210 may include a shell 211 and a vibration unit 212. In some embodiments, the shell 211 may be connected to the acoustic transducer 220 to enclose a structure having an acoustic cavity 213. The connection between the shell 211 and the acoustic transducer 120 may be a physical connection. In some embodiments, the vibration unit 212 may be located in the acoustic cavity 213. In some embodiments, the vibration unit 212 may separate the acoustic cavity 213 into a first acoustic cavity 2131 and a second acoustic cavity 2132. For example, the vibration unit 212 may form a second acoustic cavity 2132 with the shell 211; the vibration unit 212 may form a first acoustic cavity 2131 with the acoustic transducer 220.

[0043] In some embodiments, the first acoustic cavity 2131 may be in acoustic communication with the acoustic transducer 220. By way of example only, the first acoustic cavity 2131 may include an air inlet 221, and the acoustic transducer 220 may be in acoustic communication with the first acoustic cavity 2131 through the air inlet 221. Figure 2 The depiction of a single air inlet 221 is for illustration only and is not intended to limit the scope of the present invention. It should be understood that the vibration sensor 200 may include more than one air inlet. For example, the vibration sensor 200 may include multiple air inlets arranged in an array.

[0044] In some embodiments, along the vibration direction of the vibration unit 212 (eg Figure 2 As shown), the height H1 of the first acoustic cavity 2131 is 1-500um, and the height H1 of the first acoustic cavity 2131 refers to the distance between the surface of the mass element 2121 close to the acoustic transducer 220 and the surface of the shell 211 and the acoustic transducer 220 (or substrate) close to the mass element 2121. Preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-450um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-400um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-350um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-300um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-250um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-200um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-150um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-100um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-80um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-60um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-40um. More preferably, along the vibration direction of the vibration unit 212, the height H1 of the first acoustic cavity 2131 is 1-20um.

[0045] In some embodiments, the second acoustic cavity 2132 may have an open structure, that is, it is directly connected to the outside world. For example, the second acoustic cavity 2132 may be connected to the outside world through a hole structure or an opening structure provided on the housing 211. In this case, the air pressure change of the second acoustic cavity 2132 has almost no effect on the vibration of the vibration unit 212, but the air-conducted sound in the environment may affect the performance of the vibration sensor 200. In order to reduce the influence of the air-conducted sound in the environment, in some embodiments, the second acoustic cavity 2132 may be a sealed cavity structure. In some embodiments, the volume of the second acoustic cavity 2132 may be greater than the volume of the first acoustic cavity 2131, so as to reduce the influence of the air pressure change of the second acoustic cavity 2132 on the vibration of the vibration unit 212 during the vibration of the vibration unit 212. In some embodiments, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-2000um, and the height H2 of the second acoustic cavity 2132 refers to the distance between the surface of the mass element 2121 away from the acoustic transducer 220 and the inner surface of the shell 211 parallel to the mass element 2121. Preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-1000um. Preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-500um. Preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-450um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-400um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-350um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-300um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-250um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 1-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 10-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 20-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 30-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 40-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 50-200 um.More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 60-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 70-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 80-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 90-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 100-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 120-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 140-200um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 160-200 um. More preferably, along the vibration direction of the vibration unit 212, the height H2 of the second acoustic cavity 2132 may be 180-200 um.

[0046] In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 10:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 9:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 8:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 8:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 7:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 6:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 5:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 4:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 3:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 2:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 1.5:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 2.5:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 3.5:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 4.5:1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 5.5:1. In some embodiments, along the vibration direction of the vibration unit 212 , a ratio of a height H2 of the second acoustic cavity 2132 to a height H1 of the first acoustic cavity 2131 may be 6.5:1.In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 7.5: 1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 8.5: 1. In some embodiments, along the vibration direction of the vibration unit 212, the ratio of the height H2 of the second acoustic cavity 2132 to the height H1 of the first acoustic cavity 2131 may be 9.5: 1.

[0047] In some embodiments, the vibration unit 212 may include a mass element 2121 and an elastic element 2122. In some embodiments, the mass element 2121 and the elastic element 2122 may be physically connected, for example, by gluing. As an example only, the elastic element 2122 may be a material having a certain viscosity, directly bonded to the mass element 2121. In some embodiments, the elastic element 2122 may be a high temperature resistant material, so that the elastic element 2122 maintains performance during the processing and manufacturing process of the vibration sensor 200. In some embodiments, when the elastic element 2122 is in an environment of 200°C to 300°C, its Young's modulus and shear modulus do not change or change very little (such as the change is within 5%), wherein the Young's modulus can be used to characterize the deformation ability of the elastic element 2122 when stretched or compressed, and the shear modulus can be used to characterize the deformation ability of the elastic element 2122 when sheared. In some embodiments, the elastic element 2122 may be a material with good elasticity (i.e., easy to elastically deform), so that the vibration unit 212 can vibrate in response to the vibration of the housing 211. As an example only, the material of the elastic element 2122 may include silicone rubber, silicone gel, silicone sealant, etc. or any combination thereof. In some embodiments, the Shore hardness of the elastic element 2122 may be 1-50HA. Preferably, the Shore hardness of the elastic element 2122 may be 1-45HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-40HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-35HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-30HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-25HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-20HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-15HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-10HA. More preferably, the Shore hardness of the elastic element 2122 may be 1-5HA. More preferably, the Shore hardness of the elastic element 2122 may be 15HA.

[0048] The mass element 2121 may also be referred to as a mass block. In some embodiments, the material of the mass element 2121 may be a material with a density greater than a certain density threshold (e.g., 6 g / cm 3 ) material, for example, metal. As an example only, the material of the mass element 2121 may include lead, copper, silver, tin, stainless steel, alloy, etc. or any combination thereof. Since the higher the density of the material of the mass element 2121, the smaller the size, the mass element 2121 is made of a material with a density greater than a certain density threshold, which can reduce the size of the vibration sensor 200 to a certain extent. In some embodiments, the material density of the mass element 2121 has a great influence on the resonance peak and sensitivity of the frequency response curve of the vibration sensor 200. Under the same volume, the greater the density of the mass element 2121, the greater its mass, the resonance peak of the vibration sensor 200 moves to a low frequency, and the sensitivity increases. In some embodiments, the material density of the mass element 2121 is 6 to 20 g / cm 3 Preferably, the material density of the mass element 2121 is 6 to 15 g / cm 3 More preferably, the material density of the mass element 2121 is 6-10 g / cm 3 More preferably, the material density of the mass element 2121 is 6-8 g / cm 3 In some embodiments, the mass element 2121 and the elastic element 2122 may be made of different materials and assembled (e.g., glued) together to form the vibration unit 212. In some embodiments, the mass element 2121 and the elastic element 2122 may also be made of the same material and formed into an integral part to form the vibration unit 212.

[0049] In some embodiments, the thickness of the mass element 2121 along its vibration direction may be 50-1000um. Preferably, the thickness of the mass element 2121 along its vibration direction may be 60-900um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 70-800um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 80-700um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 90-600um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 100-500um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 100-400um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 100-300um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 100-200um. More preferably, the thickness of the mass element 2121 along its vibration direction may be 100-150 um.

[0050] In some embodiments, the elastic element 2122 may be connected to a side wall of the mass element 2121 around the elastic element 2122 . Figure 3 FIG. 2 is a schematic diagram of a connection method between a mass element 2121 and an elastic element 2122 according to some embodiments of the present specification. Figure 2-4C As shown, the inner side 2124 of the elastic element 2122 is connected to the side wall of the mass element 2121. The inner side 2124 of the elastic element 2122 may refer to the side where the space surrounded by the elastic element 2122 is located. The side wall of the mass element 2121 may refer to the side of the mass element 2121 parallel to the vibration direction. The upper and lower surfaces of the mass element 2121 are approximately perpendicular to the vibration direction, and are used to define the second acoustic cavity 2132 and the first acoustic cavity 2131, respectively. Since the elastic element 2122 is connected to the side wall of the mass element 2121 in a surrounding manner, during the vibration of the vibration unit 212 along the vibration direction, the momentum of the mass element 2121 is converted into a force acting on the elastic element 2122, causing the elastic element 2122 to undergo shear deformation. Compared with tensile and compressive deformation, shear deformation reduces the spring coefficient of the elastic element 2122, which reduces the resonant frequency of the vibration sensor 200, thereby increasing the vibration amplitude of the mass element 2121 during the vibration of the vibration unit 212, and improving the sensitivity of the vibration sensor 200. In addition, when the elastic element 2122 undergoes shear deformation, as the amount of shear deformation increases, the direction of the shear force acting on the mass element 2121 changes accordingly, and the proportion of the shear force in the vibration direction increases. Therefore, the elastic element 2122 can provide sufficient elastic force for the mass element 2121 in the vibration direction, thereby ensuring the vibration performance of the vibration unit 212.

[0051] In some embodiments, the mass element 2121 and the elastic element 2122 in the vibration unit 212 can be regarded as an additional resonance system outside the resonance system of the acoustic transducer 220. In some embodiments, the additional resonance system can adjust the original vibration characteristics of the vibration sensor 200 (i.e., the vibration characteristics under the action of the original resonance system of the acoustic transducer 220), so that the original resonance frequency of the vibration sensor 200 (i.e., the resonance frequency under the action of the original resonance system of the acoustic transducer 220) changes. At the same time, this setting can be regarded as introducing a new resonance system into the original resonance system of the vibration sensor 200, thereby introducing a new resonance peak. The resonance frequency of the new resonance peak is less than the resonance frequency of the acoustic transducer 220, so that the vibration sensor 200 has a higher sensitivity. For a detailed description of the sensitivity of the vibration sensor 200, please refer to Figure 6-8 Detailed description.

[0052] In some embodiments, the resonant frequency of the vibration sensor 200 may be 1000 Hz to 5000 Hz. Preferably, the resonant frequency of the vibration sensor 200 may be 1500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2000 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 3000 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 3500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 4000 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 4500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 1000 Hz to 4500 Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 1000Hz to 4000Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 1500Hz to 4500Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2000Hz to 4000Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2000Hz to 3500Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2000Hz to 3000Hz. More preferably, the resonant frequency of the vibration sensor 200 may be 2000Hz to 2500Hz. In some embodiments, the resonant frequency of the vibration sensor 200 may be determined by the parameters of the mass element 2121 and the elastic element 2122. In some embodiments, the parameters used to determine the resonant frequency may include, but are not limited to, the mass of the mass element 2121, the mass of the elastic element 2122, the stiffness of the elastic element 2122, the Young's modulus of the elastic element 2122, the shear modulus of the elastic element 2122, the equivalent stiffness of the elastic element 2122, or the spring constant of the elastic element 2122. In some embodiments, the vibration sensor 200 can have different resonant frequencies by adjusting the parameters of the mass element 2121 and the elastic element 2122. For example, when the mass of the mass element 2121 remains unchanged, the smaller the spring constant of the elastic element 2122 is adjusted, the lower the resonant frequency of the vibration sensor 200. By reducing the resonant frequency of the vibration sensor 200, the vibration amplitude of the mass element 2121 can be increased during the vibration of the vibration unit 212, thereby improving the sensitivity of the vibration sensor 200.

[0053] In some embodiments, the shape of the elastic element 2122 may be adapted to the shape of the mass element 2121. For example, the elastic element 2122 may be a tubular structure, and the open end of the tubular structure has the same cross-sectional shape as the mass element 2121 in the cross section perpendicular to the vibration direction of the mass element 2121. The open end of the elastic element 2122 may be an end connected to the mass element 2121. Figure 3 As shown, the shape of the mass element 2121 on the cross section perpendicular to the vibration direction of the mass element 2121 is a quadrilateral, and the area surrounded by the elastic element 2122 is a tube, which has a quadrilateral hole on the cross section perpendicular to the vibration direction of the mass element 2121. As an example only, the shape of the mass element 2121 on the cross section perpendicular to the vibration direction of the mass element 2121 can also include a regular shape (for example, a circle, an ellipse, a sector, a rounded rectangle, a polygon) and an irregular shape. Correspondingly, the shape of the tube surrounded by the elastic element 2122 on the cross section perpendicular to the vibration direction of the mass element 2121 can include a tube with a regular or irregular shaped aperture. This specification does not limit the shape of the outer side 2125 of the tubular elastic element 2122. The outer side 2125 of the elastic element 2122 can be the side opposite to the inner side 2124 of the elastic element 2122. For example, the shape of the outer side of the tubular elastic element 2122 may include a cylindrical shape, an elliptical cylindrical shape, a conical shape, a rounded rectangular cylindrical shape, a rectangular cylindrical shape, a polygonal cylindrical shape, an irregular cylindrical shape, etc. or any combination thereof. Figure 3 As shown, the outer side of the tubular elastic element 2122 may be in the shape of a quadrilateral.

[0054] In some embodiments, Figure 3As shown, the width W of the elastic element 2122 surrounding and connected to the side wall of the mass element 2121 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 10-500um. Preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 20-450um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 30-400um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 40-350um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 50-300um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 60-250 um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 70-200 um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 80-150 um. More preferably, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 may be 90-100 um.

[0055] In some embodiments, the width W of the elastic element 2122 from one side close to the mass element 2121 to the other side away from the mass element 2121 varies along the vibration direction. That is, the elastic element 2122 may include multiple cross sections perpendicular to the vibration direction, and the width of the elastic element 2122 corresponding to each cross section is the length along the direction perpendicular to the boundary of the elastic element 2122 in the cross section, and the width of the elastic element 2122 in multiple cross sections may be different. Figures 4A-4BAs shown, the elastic element 2122 can bulge outward and / or inward relative to the mass element 2121. As described herein, the elastic element 2122 can bulge outward relative to the mass element 2121, which means that the distance between at least a portion of the outer side 2125 of the elastic element 2122 and the axis of the first acoustic cavity 2131 (Z axis as shown in the figure) gradually increases along the direction from the mass element 2121 to the acoustic-electric transducer element; the elastic element 2122 can bulge inward relative to the mass element 2121, which means that the distance between at least a portion of the inner side 2124 of the elastic element 2122 and the axis of the first acoustic cavity 2131 gradually decreases along the direction from the mass element 2121 to the acoustic-electric transducer element. The axis of the first acoustic cavity 2131 (Z axis as shown in the figure) can refer to the geometric center line of the first acoustic cavity 2131 parallel to the vibration direction. This outward and / or inward bulging may cause the width W of the elastic element 2122 to vary from one side close to the mass element 2121 to the other side away from the mass element 2121 along the vibration direction of the mass element 2121. Figure 4B As shown, due to the inward bulging, the width of the portion of the elastic element 2122 away from the mass element 2121 is greater than the width of the portion close to the mass element 2121. The amount of change in width can be represented by the difference between the minimum width value and the maximum width value of the width. In some embodiments, the amount of change in width can be less than or equal to 300um. In some embodiments, the amount of change in width can be less than or equal to 250um. In some embodiments, the amount of change in width can be less than or equal to 200um. In some embodiments, the amount of change in width can be less than or equal to 150um. In some embodiments, the amount of change in width can be less than or equal to 100um. In some embodiments, the amount of change in width can be less than or equal to 50um. In some embodiments, the amount of change in width can be less than or equal to 30um. In some embodiments, the width can also remain unchanged, that is, the amount of change in width can be 0. In some embodiments, see Figure 4C, the elastic element 2122 may be recessed outwardly and / or inwardly relative to the mass element 2121. As described herein, the elastic element 2122 may be recessed outwardly relative to the mass element 2121, which means that the distance between at least a portion of the inner side 2124 of the elastic element 2122 and the axis of the first acoustic cavity 2131 (Z axis as shown in the figure) first gradually decreases and then gradually increases along the direction from the mass element 2121 to the acoustic-electric transducer element; the elastic element 2122 may be recessed inwardly relative to the mass element 2121, which means that the distance between at least a portion of the outer side 2125 of the elastic element 2122 and the axis of the first acoustic cavity 2131 first gradually decreases and then gradually increases along the direction from the mass element 2121 to the acoustic-electric transducer element. For example, the outer side 2125 of the elastic element 2122 may be recessed inwardly, and the inner side 2124 of the elastic element 2122 may be recessed outwardly. For another example, the outer side 2125 of the elastic element 2122 may be concave inward, and the inner side 2124 of the elastic element 2122 may also bulge inward. With this arrangement, after the shear deformation of the elastic element 2122 increases to a certain extent, the shear force of the elastic element 2122 can be further increased, so that the elastic element 2122 can provide sufficient elastic force for the mass element 2121 in the vibration direction, thereby ensuring the vibration performance of the vibration unit 212.

[0056] In some embodiments, Figure 2As shown, the surface A of the elastic element 2122 away from the acoustic transducer 220 (i.e., the upper surface of the elastic element 2122, the upper surface of the elastic element 2122 is the surface of the elastic element 2122 away from the acoustic transducer 220) may be lower than the surface B of the mass element 2121 away from the acoustic transducer 220 (i.e., the upper surface of the mass element 2121, the upper surface of the mass element 2121 is the surface of the mass element 2121 away from the acoustic transducer 220). Generally, since the elastic element 2122 is an elastic colloid, during the preparation of the vibration unit 212, due to operational reasons, the elastic element 2122 may overflow onto the surface B of the mass element 2121, which may affect the packaging of the shell 211 (even causing the shell 211 to be unpackaged), resulting in a change in the volume of the second acoustic cavity 2132, and an increase in the equivalent stiffness of the elastic element 2122, thereby reducing the performance (e.g., sensitivity) of the vibration sensor 200. The equivalent stiffness of the elastic element 2122 may be a parameter that can reflect the total deformation (e.g., including tensile and compressive deformation and shear deformation) properties of the elastic element 2122. In some embodiments, the height difference between the surface A of the elastic element 2122 away from the acoustic transducer 220 and the surface B of the mass element 2121 away from the acoustic transducer 220 may be less than 2 / 3 of the thickness of the mass element 2121. Preferably, the height difference between the surface A of the elastic element 2122 away from the acoustic transducer 220 and the surface B of the mass element 2121 away from the acoustic transducer 220 may be less than 1 / 2 of the thickness of the mass element 2121. More preferably, the height difference between the surface A of the elastic element 2122 away from the acoustic transducer 220 and the surface B of the mass element 2121 away from the acoustic transducer 220 may be less than 1 / 3 of the thickness of the mass element 2121.

[0057] In some embodiments, the elastic element 2122 may extend toward the acoustic transducer 220 and directly or indirectly connect to the acoustic transducer 220. For example, Figure 2 As shown, one end of the elastic element 2122 extending toward the acoustic transducer 220 may be directly connected to the acoustic transducer 220. The connection between the elastic element 2122 and the acoustic transducer 220 may be a physical connection, such as adhesive bonding. In some embodiments, the elastic element 2122 and the housing 211 may be in direct contact or there may be a gap. For example, Figure 2 As shown, there may be a gap between the elastic element 2122 and the housing 211. The size of this gap may be adjusted by the designer according to the size of the vibration sensor 200. For another example, Figure 5 FIG. 2 is a schematic diagram of a vibration receiver 210 according to some embodiments of the present specification. Figure 5As shown, the elastic element 2122 can be in direct contact with the housing 211, which can reduce the flow of the elastic element 2122 during the preparation of the vibration receiver 210, so as to better control the size and shape of the elastic element, and can reduce the size of the vibration sensor 200. Compared with the direct contact between the elastic element 2122 and the housing 21, the presence of a gap between the elastic element 2122 and the housing 211 may increase the size of the vibration sensor 200, but can reduce the equivalent stiffness of the elastic element 2122, increase the elasticity of the elastic element 2122, and thus increase the vibration amplitude of the mass element 2121 during the vibration of the vibration unit 212, which can reduce the resonant frequency of the vibration sensor 200 and improve the sensitivity of the vibration sensor 200.

[0058] In some embodiments, at least one of the housing 211 and the mass element 2121 may be provided with at least one pressure relief hole. Figure 2 and Figure 5 As shown, at least one pressure relief hole 2111 may be provided on the housing 211. The pressure relief hole 2111 may penetrate the housing 211. Figure 2-5 As shown, at least one pressure relief hole 2123 may be provided on the mass element 2121. The pressure relief hole 2123 may penetrate the mass element 2121. The pressure relief hole 2123 may allow the gas in the first acoustic cavity 2131 and the second acoustic cavity 2132 to circulate, and the pressure relief hole 2111 may allow the gas in the second acoustic cavity 2132 to circulate with the outside, thereby balancing the pressure changes inside the first acoustic cavity 2131 and the second acoustic cavity 2332 caused by the temperature changes during the preparation process of the vibration sensor 200 (for example, during the reflow process), and reducing or preventing the damage of the components of the vibration sensor 200 caused by the pressure changes, such as cracking, deformation, etc. In some embodiments, at least one pressure relief hole 2111 may be provided on the housing 211, and when the mass element 2121 vibrates, the pressure relief hole 2111 may be used to reduce the damping generated by the gas inside the second acoustic cavity 2332.

[0059] In some embodiments, the pressure relief hole 2111 and / or the pressure relief hole 2123 may be a single hole. In some embodiments, the diameter of the single hole may be 1-50um. Preferably, the diameter of the single hole may be 2-45um. More preferably, the diameter of the single hole may be 3-40um. More preferably, the diameter of the single hole may be 4-35um. More preferably, the diameter of the single hole may be 5-30um. More preferably, the diameter of the single hole may be 5-25um. More preferably, the diameter of the single hole may be 5-20um. More preferably, the diameter of the single hole may be 6-15um. More preferably, the diameter of the single hole may be 7-10um. In some embodiments, the pressure relief hole 2111 and / or the pressure relief hole 2123 may be an array composed of a certain number of micropores. By way of example only, the number of micropores may be 2-10. In some embodiments, the diameter of each micropore may be 0.1-25um. Preferably, the diameter of each micropore may be 0.5-20um. More preferably, the diameter of each micropore may be 0.5-25um. More preferably, the diameter of each micropore may be 0.5-20um. More preferably, the diameter of each micropore may be 0.5-15um. More preferably, the diameter of each micropore may be 0.5-10um. More preferably, the diameter of each micropore may be 0.5-5um. More preferably, the diameter of each micropore may be 0.5-4um. More preferably, the diameter of each micropore may be 0.5-3um. More preferably, the diameter of each micropore may be 0.5-2um. More preferably, the diameter of each micropore may be 0.5-1um.

[0060] In some embodiments, air-conducted sound in the environment may affect the performance of the vibration sensor 200. In order to reduce the influence of air-conducted sound in the environment, after the vibration sensor 200 is prepared, for example, after reflow soldering, a sealing material may be used to seal at least one pressure relief hole 2111 on the housing 211. As an example only, the sealing material may include epoxy glue, silicon sealant, etc. or any combination thereof.

[0061] In some embodiments, the housing 211 and the mass element 2121 may not be provided with a pressure relief hole. In some embodiments, when the housing 211 and the mass element 2121 are not provided with a pressure relief hole, the components of the vibration sensor 200 may be prevented from being damaged due to changes in the air pressure inside the first acoustic cavity 2131 and the second acoustic cavity 2332 by increasing the connection strength between the components of the vibration sensor 200 (for example, increasing the connection strength of the glue connecting the components).

[0062] The vibration sensor 200 can convert an external vibration signal into an electrical signal. As an example only, the external vibration signal can include a vibration signal when a person speaks, a vibration signal generated by the skin moving with the human body or by other devices (such as speakers) close to the skin, and a vibration signal generated by an object or air in contact with the vibration sensor 200, or any combination thereof. When the vibration sensor 200 is working, the external vibration signal can be transmitted to the vibration unit 212 through the housing 211, and the mass element 2121 of the vibration unit 212 vibrates in response to the vibration of the housing 211 driven by the elastic element 2122. The vibration of the mass element 2121 can cause a volume change in the first acoustic cavity 2131, thereby causing a change in the air pressure in the first acoustic cavity 2131, and converting the change in the air pressure in the cavity into a change in the sound pressure in the cavity. The acoustic transducer 220 can detect the change in the sound pressure of the first acoustic cavity 2131 and convert it into an electrical signal. For example, the acoustic transducer 220 may include an air inlet 221, and the sound pressure change in the first acoustic cavity 2131 may act on the diaphragm of the acoustic transducer 220 through the air inlet 221, causing the diaphragm to vibrate (or deform) to generate an electrical signal. Further, the electrical signal generated by the acoustic transducer 220 may be transmitted to an external electronic device. For example, Figure 2 As shown, the acoustic transducer 220 may include an interface 222. The interface 222 may be wired (e.g., electrically connected) or wirelessly connected to an internal element (e.g., a processor) of an external electronic device. The electrical signal generated by the acoustic transducer 220 may be transmitted to the external electronic device through the interface 222 in a wired or wireless manner. In some embodiments, the external electronic device may include a mobile device, a wearable device, a virtual reality device, an augmented reality device, etc., or any combination thereof. In some embodiments, the mobile device may 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 may include a smart bracelet, a headset, a hearing aid, a smart helmet, a smart watch, smart clothing, a smart backpack, a smart accessory, etc., or any combination thereof. In some embodiments, the virtual reality device and / or the augmented reality device may 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 may include Google Glass, Oculus Rift, Hololens, Gear VR, etc.

[0063] It should be noted that the above description of the vibration sensor 200 and its components is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor 200 under the guidance of this specification. In some embodiments, the elastic element 2122 can be provided with at least one pressure relief hole. The pressure relief hole can penetrate the elastic element 2122. These modifications and changes are still within the scope of this specification.

[0064] Figure 6 is a simplified structural diagram of a vibration system 600 according to some embodiments of the present specification. Figure 1-5 The vibration receiver shown may be described by a vibration system 600. Figure 6 As shown, the vibration system 600 may include a housing 611 enclosing a closed cavity and a vibration unit 612 located in the closed cavity. The vibration unit 612 may include a mass element 6121 and an elastic element 6122. The elastic element 6122 may be connected between the mass element 6121 and the housing 611. In some embodiments, the elastic element 6122 may be a spring. For ease of description, the mass of the housing 611 may be represented as m, and the mass of the mass element 6121 may be represented as M m , the mass of the elastic element 6122 can be expressed as K m , the damping of the system can be expressed as R m .

[0065] Assume that the displacement ξ1 of the housing 611 during vibration can be expressed as:

[0066] ξ1=ξ 10 *e i*ω*t (1)

[0067] Among them, ξ 10 is the vibration amplitude when the shell 611 vibrates, i is an imaginary unit, ω is the vibration frequency when the shell 611 vibrates, and t is the vibration time when the shell 611 vibrates. The motion equation of the mass element 6121 can be expressed as:

[0068]

[0069] Here, ξ2 is the displacement of mass element 6121 when it vibrates.

[0070] Let the relative displacement ξ between the mass element 6121 and the housing 611 be ξ=ξ1-ξ2, then the amplitude of the relative displacement ξ a It can be expressed as:

[0071]

[0072] Among them, a 10is the acceleration amplitude of the housing 611, and the force impedance modulus Resistance Abs is the absolute value function.

[0073] The vibration amplitude Δh of the mass element 6121 relative to the housing 611 under unit acceleration can be expressed as:

[0074]

[0075] Let K m =ω0 2 *M m , where ω0 is the resonant frequency of the vibration system 600, we can get:

[0076]

[0077] For the sensitivity of the vibration system 600 in the flat region of the frequency response curve, ω<<ω0, and for the convenience of calculation, ω=1 is taken, then the vibration amplitude of the mass element 6121 in the low frequency range (for example, the flat region of the frequency response curve) can be expressed as:

[0078]

[0079] In the practical application of the vibration system 600, ω0>>1, then the vibration amplitude of the mass element 6121 in the low frequency range in the practical application of the vibration system 600 can be expressed as:

[0080]

[0081] The quality factor Substituting into formula (7), the vibration amplitude of mass element 6121 in the low frequency range can be expressed as:

[0082]

[0083] The sensitivity of the vibration system 600 in the flat region of the frequency response curve is mainly related to the resonant frequency ω0 of the vibration system 600 and is affected by the quality factor Q m The influence of is low and can be almost ignored. Therefore, the vibration amplitude of the mass element 6121 relative to the housing 611 at low frequency (for example, the flat area of ​​the frequency response curve) under unit acceleration can be expressed as:

[0084]

[0085] It can be seen from formula (9) that the vibration amplitude of the mass element 6121 is inversely proportional to the square of the resonant frequency of the vibration system 600. Applied in other embodiments of this specification, for example, Figure 2For the vibration sensor 200 shown, the vibration amplitude of the mass element 2121 is inversely proportional to the square of the resonant frequency of the vibration sensor 200. Further, it can be seen from formula (9) that for a mechanical system (e.g., vibration sensor 100, vibration sensor 200, vibration system 600), the lower its resonant frequency, the greater the vibration amplitude of the center of gravity of its mass element (e.g., mass element 2121, mass element 6121) at low frequency (e.g., the flat area of ​​the frequency response curve of the mechanical system), and the higher its sensitivity. In some embodiments, the low frequency can be a frequency band less than 2000 Hz or less than 1000 Hz or less than 800 Hz or less than 600 Hz or less than 500 Hz. Similarly, the greater the vibration amplitude of the center of gravity of the mass element of the mechanical system at low frequency (e.g., the flat area of ​​the frequency response curve of the mechanical system), the lower the resonant frequency of the mechanical system, and the higher the sensitivity.

[0086] Therefore, in this specification, according to Figure 2 As described in , the elastic element (e.g., elastic element 2122) surrounds and is connected to the side wall of the mass element (e.g., mass element 2121), and during the vibration of the vibration unit (e.g., vibration unit 212), the elastic element undergoes shear deformation. Compared with tensile and compressive deformation, shear deformation reduces the spring constant of the elastic element and reduces the resonant frequency of the vibration sensor (e.g., vibration sensor 200), thereby increasing the vibration amplitude of the mass element during the vibration of the vibration unit and improving the sensitivity of the vibration sensor.

[0087] Further, in this specification, according to Figure 2 As described in the specification, there is a gap between the elastic element and the shell (for example, shell 211), which can reduce the stiffness of the elastic element and increase the elasticity of the elastic element, thereby increasing the vibration amplitude of the mass element during the vibration of the vibration unit, thereby reducing the resonant frequency of the vibration sensor and improving the sensitivity of the vibration sensor.

[0088] The resonant frequency of the vibration system 600 can be determined by the mass M of the mass element 6121. m 、The mass K of the elastic element 6122 m and the system damping R m Determine, where the damping R of the system m The mass M of the mass element 6121 is positively correlated with the resonant frequency of the vibration system 600. m and the mass K of the elastic element 6122 mThe sum is negatively correlated with the resonant frequency of the vibration system 600. In addition, it can be seen from formula (9) that for mechanical systems with the same resonant frequency (e.g., vibration sensor 100, vibration sensor 200, vibration system 600), the vibration amplitudes of the center of gravity of their mass elements (e.g., mass element 2121, mass element 6121) at low frequencies (e.g., the flat region of the frequency response curve of the mechanical system) are approximately the same. Regarding mechanical systems with approximately the same vibration amplitudes of the center of gravity of mass elements at low frequencies, how to improve the sensitivity of the mechanical system by setting the structure and / or parameters of each component of the mechanical system is described below. Figure 7-8 Introduction.

[0089] Figure 7 is a schematic diagram of the structure of a vibration sensor 700 according to some embodiments of this specification. Figure 7 As shown, the vibration sensor 700 may include a vibration receiver 710 and an acoustic transducer 720. The vibration receiver 710 may include a shell 711 and a vibration unit 712. The shell 711 may be connected to the acoustic transducer 720 to form a packaging structure having an acoustic cavity 713. The vibration unit 712 may be located in the acoustic cavity 713 of the packaging structure and separate the acoustic cavity 713 into a first acoustic cavity 7131 and a second acoustic cavity 7132. The vibration unit 712 may include a mass element 7121, an elastic film 7122, and a support component 7123. Figure 7 As shown, the mass element 7121 can be disposed on the upper surface of the elastic film 7122. In some embodiments, the material of the elastic film 7122 can include a polymer elastic film such as a polytetrafluoroethylene (PTFE) film and a polydimethylsiloxane (PDMS) film, or a composite film (for example, a plastic film (such as polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) and polyester (PET)), cellophane, paper and / or metal foil AL). The support component 7123 can be used to support the elastic film 7122. Figure 7 As shown, the elastic film 7122 is fixed to one end surface of the support member 450. The other end surface of the support member 450 is connected to the acoustic transducer 720.

[0090] It should be noted that if Figure 7As shown, the mass element 7121 is disposed above the first acoustic cavity 7131 through the elastic film 7122, and the cross-sectional area of ​​the mass element 7121 perpendicular to its vibration direction is smaller than the cross-sectional area of ​​the first acoustic cavity 7131 perpendicular to the vibration direction of the mass element 7121. As an example only, the cross-sectional area of ​​the mass element 7121 perpendicular to its vibration direction is less than or equal to 2 / 3 of the cross-sectional area of ​​the first acoustic cavity 7131 perpendicular to the vibration direction of the mass element 7121. For another example, the cross-sectional area of ​​the mass element 7121 perpendicular to its vibration direction is less than or equal to 1 / 3 of the cross-sectional area of ​​the first acoustic cavity 7131 perpendicular to the vibration direction of the mass element 7121.

[0091] The sensitivity of the vibration sensor 700 may be proportional to the ratio of the pressure change of the first acoustic cavity 7131 to the initial pressure of the first acoustic cavity 7131 or the ratio of the volume change of the first acoustic cavity 7131 to the initial volume of the first acoustic cavity 7131. In other words, the sensitivity of the vibration sensor 700 may be expressed as:

[0092]

[0093] Wherein, Δp is the pressure change of the first acoustic cavity 7131, p0 is the initial pressure of the first acoustic cavity 7131, ΔV is the volume change of the first acoustic cavity 7131, and V0 is the initial volume of the first acoustic cavity 7131. In some embodiments, the acoustic transducer 720 may include at least one air inlet 721, and the initial volume V0 of the first acoustic cavity 7131 includes the volume of the at least one air inlet 721.

[0094] like Figure 7 As shown, since the cross-sectional area of ​​the mass element 7121 perpendicular to its vibration direction is smaller than the cross-sectional area of ​​the first acoustic cavity 7131 perpendicular to the vibration direction of the mass element 7121, the up and down vibration of the mass element 7121 along its vibration direction will drive the elastic film 7122 to deform, thereby causing the volume of the first acoustic cavity 7131 to change. The shape of the change in the volume of the first acoustic cavity 7131 caused by the deformation of the elastic film 7122 can be approximated as a prism, and the volume change ΔV of the first acoustic cavity 7131 can be expressed as:

[0095]

[0096] Wherein, Δh is the vibration amplitude of the mass element 7121 , A1 is the cross-sectional area of ​​the mass element 7121 perpendicular to its vibration direction, and A0 is the cross-sectional area of ​​the first acoustic cavity 7131 perpendicular to the vibration direction of the mass element 7121 .

[0097] Further, according to formulas (10) and (11), the sensitivity of the vibration sensor 700 can be expressed as:

[0098]

[0099] Figure 8 8 is a schematic diagram of the structure of a vibration sensor 800 according to some embodiments of this specification. Figure 8 As shown, the vibration sensor 800 may include a vibration receiver 810 and an acoustic transducer 820. The vibration receiver 810 may include a shell 811 and a vibration unit 812. The shell 811 may be connected to the acoustic transducer 820 to enclose a packaging structure having an acoustic cavity 813. The vibration unit 812 may be located in the acoustic cavity 813 of the packaging structure. The vibration unit 812 may separate the acoustic cavity 813 into a first acoustic cavity 8131 and a second acoustic cavity 8132. The vibration unit 812 may include a mass element 8121 and an elastic element 8122. The elastic element 8122 may surround the side wall connected to the mass element 8121, extend toward the acoustic transducer 820 and be directly connected to the acoustic transducer 820. The structure and components of the vibration sensor 800 are similar to those of the present invention. Figure 2 The structure and components of the vibration sensor 200 described in Figure 2-5 The description in will not be repeated here.

[0100] It should be noted that if Figure 8As shown, since the elastic element 8122 is connected to the side wall of the mass element 8121 in a surrounding manner, the cross-sectional area of ​​the mass element 8121 perpendicular to its vibration direction is approximately equal to the cross-sectional area of ​​the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121. In some embodiments, the deviation between the cross-sectional areas of the mass element 8121 and the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121 can be less than 25%. In some embodiments, the deviation refers to the ratio of the absolute value of the difference between the cross-sectional areas of the mass element 8121 and the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121 to the cross-sectional area of ​​the mass element 8121 perpendicular to the vibration direction of the mass element 8121. For example, the cross-sectional area of ​​the mass element 8121 perpendicular to its vibration direction is 3 / 4-5 / 4 of the cross-sectional area of ​​the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121. In some embodiments, the cross-sectional area of ​​the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121 may be the area of ​​the cross section of the first acoustic cavity 8131 near the mass element 8121. Wherein, near may mean that the distance between the cross section and the lower surface of the mass element 8121 is less than the distance between the cross section and the upper surface of the acoustic transducer 820. In some embodiments, the lower surface of the mass element 8121 refers to the surface of the mass element 8121 near the acoustic transducer 820, and the upper surface of the acoustic transducer 820 refers to the surface of the acoustic transducer 820 near the mass element 8121. In some embodiments, the cross-sectional area of ​​the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121 may be the average of the areas of all cross sections of the first acoustic cavity 8131 perpendicular to the vibration direction. In some embodiments, the cross-sectional area of ​​the mass element 8121 perpendicular to the vibration direction of the mass element 8121 may be the area of ​​the lower surface of the mass element 8121. In some embodiments, the cross-sectional area of ​​the mass element 8121 perpendicular to the vibration direction of the mass element 8121 may also be the average of the areas of all cross sections of the mass element 8121 perpendicular to the vibration direction. In some embodiments, the cross-sectional area of ​​the mass element 8121 perpendicular to the vibration direction of the mass element 8121 may also be the area of ​​the upper surface of the mass element 8121. In some embodiments, the upper surface of the mass element 8121 refers to the surface of the mass element 8121 away from the acoustic transducer 820.

[0101] like Figure 8As shown, since the cross-sectional area of ​​the mass element 8121 perpendicular to its vibration direction is approximately equal to the cross-sectional area of ​​the first acoustic cavity 8131 perpendicular to the vibration direction of the mass element 8121, the mass element 8121 vibrates up and down along its vibration direction, causing the volume of the first acoustic cavity 8131 to change. Since the shape of the volume change of the first acoustic cavity 8131 caused by the mass element 8121 can be approximately cylindrical (or rectangular), the volume change ΔV of the first acoustic cavity 8131 can be expressed as:

[0102] ΔV≈ΔhA0 (13),

[0103] Wherein, Δh is the vibration amplitude of the mass element 8121 , and A0 is the cross-sectional area of ​​the first acoustic cavity 8131 in a direction perpendicular to the vibration direction of the mass element 8121 .

[0104] Further, according to formulas (10) and (13), the sensitivity of the vibration sensor 800 can be expressed as:

[0105]

[0106] Wherein, Δp is the pressure change of the first acoustic cavity 8131, p0 is the initial pressure of the first acoustic cavity 8131, and V0 is the initial volume of the first acoustic cavity 8131. In some embodiments, the acoustic transducer 820 may include at least one air inlet 821, and the initial volume V0 of the first acoustic cavity 8131 includes the volume of the at least one air inlet 821.

[0107] It can be seen from formula (14) that the sensitivity of the vibration sensor 800 can be proportional to the ratio of the product of the vibration amplitude Δh of the mass element 8121 and the cross-sectional area A0 of the first acoustic cavity 8131 in the vibration direction perpendicular to the mass element 8121 to the initial volume V0 of the first acoustic cavity 8131. In some embodiments, the sensitivity s of the vibration sensor 800 can be made greater than a threshold value by designing the structural parameters of the vibration sensor 800. For example, according to the above formula (9), the resonant frequency ω0 of the vibration sensor 800 can be designed by designing the structural parameters of the vibration sensor 800, thereby affecting the vibration amplitude Δh of the mass element 8121, so that the sensitivity of the vibration sensor 800 meets the requirements. In some embodiments, the sensitivity s of the vibration sensor 800 can be made greater than a threshold value by setting the initial volume V0 of the first acoustic cavity 8131 and / or the cross-sectional area A0 of the first acoustic cavity 8131 in the vibration direction perpendicular to the mass element 8121. The threshold value can be adjusted by the designer according to actual needs.

[0108] It can be seen from formulas (12) and (14) that, under the premise that the initial volume V0 of the first acoustic cavity (for example, the first acoustic cavity 7131, the first acoustic cavity 8131), the cross-sectional area A0 perpendicular to the vibration direction of the mass element (for example, the mass element 7121, the mass element 8121), and the vibration amplitude Δh of the mass element are constant, when the cross-sectional area A1 of the mass element perpendicular to its vibration direction is smaller than the cross-sectional area A0 of the first acoustic cavity perpendicular to the vibration direction of the mass element, at the same resonant frequency (that is, Δh is the same), Right now Figure 8 The sensitivity of the vibration sensor 800 is greater than Figure 7 The sensitivity of the vibration sensor is shown.

[0109] To summarize, in the present specification, the sensitivity of a vibration sensor (e.g., vibration sensor 800) can be improved by setting the cross-sectional area of ​​a mass element (e.g., mass element 8121) perpendicular to its vibration direction to be approximately equal to the cross-sectional area of ​​a first acoustic cavity (e.g., first acoustic cavity 8131) perpendicular to the vibration direction of the mass element.

[0110] In some embodiments, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -40 dB. Preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -38 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -36 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -34 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -32 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -30 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -28 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -27 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -26 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -24 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -22 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -20 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -18 dB. More preferably, in the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -16 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -14 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to 12 dB. More preferably, within the frequency range of 100 Hz to 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -10 dB.

[0111] It should be noted that the above Figure 6-8 The description of the vibration sensor and its components is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor under the guidance of this specification. These modifications and changes are still within the scope of this specification.

[0112] Fig. 9is a schematic diagram of the structure of a vibration sensor 900 according to some embodiments of this specification. Fig. 9 As shown, the vibration sensor 900 may include a vibration receiver 910 and an acoustic transducer 920. The vibration receiver 910 may include a housing 911 and a vibration unit 912. The housing 911 may form an acoustic cavity 913. The vibration unit 912 may be located in the acoustic cavity 913 and divide the acoustic cavity 913 into a first acoustic cavity 9131 and a second acoustic cavity 9132. The vibration unit 912 may include a mass element 9121 and an elastic element 9122. The elastic element 9122 may surround the side wall connected to the mass element 9121, extend toward the acoustic transducer 920 and indirectly connect to the acoustic transducer 920. The structure and components of the vibration sensor 900 are similar to those of the present invention. Figure 2 The structure and components of the vibration sensor 200 described in Figure 2-5 The description in will not be repeated here.

[0113] In some embodiments, the vibration receiver 910 may further include a substrate 914. The substrate 914 may be used to fix and / or support other components of the vibration sensor 900. For example, the housing 911 may be physically connected to the substrate 914 to enclose an acoustic cavity 913. The substrate 914 may be disposed on the acoustic transducer 920. The end of the elastic element 9122 that may extend toward the acoustic transducer 920 may be connected to the substrate 914, so that the substrate may be used to fix and support the vibration unit 912. The provision of the substrate allows the vibration receiver 910 to be processed, produced, and sold as an independent component. The vibration receiver 910 with the substrate may be directly physically connected (e.g., glued) to the existing acoustic transducer 920 to obtain the vibration sensor 900, which simplifies the production process of the vibration sensor 900 and improves the process flexibility of producing the vibration sensor 900. In some embodiments, the thickness of the substrate may be 10um to 300um. Preferably, the thickness of the substrate may be 20um to 250um. More preferably, the thickness of the substrate may be 30um to 200um. More preferably, the thickness of the substrate may be 40um to 150um. More preferably, the thickness of the substrate may be 50um to 150um. More preferably, the thickness of the substrate may be 60um to 130um. More preferably, the thickness of the substrate may be 70um to 110um. More preferably, the thickness of the substrate may be 80um to 90um. In some embodiments, the material of the substrate may include metal (e.g., iron, copper, stainless steel, etc.), alloy, non-metal (plastic, rubber, resin), etc. or any combination thereof.

[0114] In some embodiments, the substrate 914 may include an air outlet 9141. The air outlet 9141 overlaps or partially overlaps with the projection of the air inlet 921 of the acoustic transducer 920 on the connection surface between the substrate 914 and the acoustic transducer 920, so that the sound pressure change in the first acoustic cavity 9131 can act on the acoustic transducer 920 through the air outlet 9141 and the air inlet 921 to generate an electrical signal.

[0115] In some embodiments, the resonant frequency of the vibration sensor 900 may be 2500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 3000 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 3500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 4000 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 4500 Hz to 5000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 2500 Hz to 4500 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 2500 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 2500 Hz to 3500 Hz. More preferably, the resonant frequency of the vibration sensor 900 may be 2500 Hz to 3000 Hz. In some embodiments, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 900 is greater than or equal to -27 dB. Preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -26 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -24 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -22 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -20 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -18 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -16 dB. More preferably, within a frequency range of less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -14 dB.

[0116] More preferably, within a frequency range less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to 12 dB.

[0117] More preferably, within a frequency range less than 1000 Hz, the sensitivity of the vibration sensor 200 is greater than or equal to -10 dB.

[0118] Fig.10is a frequency response curve diagram of the vibration sensor 900 according to some embodiments of this specification. Fig.10 As shown, the resonance frequency of the vibration sensor 900 is about 4500 Hz. In the frequency range less than 1000 Hz, the sensitivity of the vibration sensor 200 is about -18 dB.

[0119] It should be noted that the above Figure 9-10 The description of the vibration sensor 900 and its components is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor 900 under the guidance of this specification. For example, the elastic element 9122 and the housing 911 can be in direct contact or there is a gap. These modifications and changes are still within the scope of this specification.

[0120] Fig.11 1 is a schematic diagram of the structure of a vibration sensor 1100 according to some embodiments of this specification. Fig.11 As shown, the vibration sensor 1100 may include a vibration receiver 1110 and an acoustic transducer 1120. The vibration receiver 1110 may include a shell 1111, a vibration unit 1112, and a substrate 1114. The shell 1111 may be connected to the substrate 1114 to form a packaging structure having an acoustic cavity 1113. The vibration unit 1112 may be located in the acoustic cavity 1113. The vibration unit 1112 may separate the acoustic cavity 1113 into a first acoustic cavity 11131 and a second acoustic cavity 11132. The vibration unit 1112 may include a mass element 11121 and an elastic element 11122. The elastic element 11122 may surround the side wall connected to the mass element 11121, extend toward the acoustic transducer 1120 and be directly connected to the substrate 1114. The vibration receiver 1110 may be disposed on the acoustic transducer 1120. The structure and components of the vibration sensor 1100 are similar to those of the embodiment of the present invention. Figure 2 The structure and components of the vibration sensor 200 described in Figure 2-5 The description in will not be repeated here.

[0121] In some embodiments, Fig.11As shown, the substrate 1114 may include a bottom plate 11142 and a side wall 11143. The bottom plate 11142 may be connected to the acoustic transducer 1120. The inner surface of the side wall 11143 may be connected to the elastic element 11122. In some embodiments, the outer surface of the side wall 11143 may be in close contact with the housing 1111 to achieve packaging with the housing 1111. In some embodiments, the outer surface of the side wall 11143 may not be in contact with the housing 1111, and the bottom plate 11142 of the substrate 1114 may extend to the housing 1111 and be in close contact with the housing 1111 to form a package. The provision of the side wall 11143 may reduce the flow of the elastic element 11122 during the preparation process of the vibration sensor 1100, so as to better control the shape and position of the elastic element 11122. In some embodiments, the thickness of the bottom plate 11142 is 50-150um. Preferably, the thickness of the bottom plate 11142 is 60-140um. More preferably, the thickness of the bottom plate 11142 is 70-130um. More preferably, the thickness of the bottom plate 11142 is 80-120um. More preferably, the thickness of the bottom plate 11142 is 90-110um. More preferably, the thickness of the bottom plate 11142 is 95-105um. In some embodiments, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 20-200um. Preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 30-180um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 40-160um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 50-140um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 60-120um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 70-110 um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 80-100 um. More preferably, the length of the side wall 11143 in the direction away from the bottom plate 11142 is 85-95 um.

[0122] It should be noted that the above Fig.11 The description of the vibration sensor 1100 and its components is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor 1100 under the guidance of this specification. For example, the housing 1111 and the acoustic transducer 1120 can be in contact (e.g., physically connected) or there is a gap. These modifications and changes are still within the scope of this specification.

[0123] Fig.12 is a schematic diagram of the structure of a vibration sensor 900 according to some embodiments of this specification. Fig.12As shown, the vibration sensor 1200 may include a vibration receiver 1210 and an acoustic transducer 1220. The vibration receiver 1210 may include a shell 1211 and a vibration unit 1212. The shell 1211 may be connected to the acoustic transducer 1220 to enclose a packaging structure having an acoustic cavity 1213. The vibration unit 1212 may be located in the acoustic cavity 1213 of the packaging structure. The vibration unit 1212 may separate the acoustic cavity 1213 into a first acoustic cavity 12131 and a second acoustic cavity 12132. The vibration unit 1212 may include a mass element 12121 and an elastic element 12122. The elastic element 12122 may surround the side wall connected to the mass element 12121, extend toward the acoustic transducer 1220 and be directly or indirectly connected to the acoustic transducer 1220. The structure and components of the vibration sensor 1200 are similar to those of the present invention. Figure 2 The structure and components of the vibration sensor 200 described in Figure 2-5 The description in will not be repeated here.

[0124] In some embodiments, the elastic element 12122 may include a first elastic portion 122A and a second elastic portion 122B. The two ends of the first elastic portion 122A are respectively connected to the side wall of the mass element 12121 and the second elastic portion 122B. The second elastic portion 122B extends toward the acoustic transducer 1220 and is directly or indirectly connected to the acoustic transducer 1220. For example, one end of the second elastic portion 122B extending toward the acoustic transducer 1220 may be directly physically connected (e.g., glued) to the acoustic transducer 1220. For another example, the vibration receiver 1210 may include a substrate, and one end of the second elastic portion 122B extending toward the acoustic transducer 1220 may be connected to the acoustic transducer 1220 through the substrate. The substrate and Fig. 9 and Fig.10 The substrates 914 and 1114 described in the same or similar manner may be found in Fig. 9 and Fig.10, which will not be repeated here. In this embodiment, the first elastic portion 122A is not connected / contacted with the acoustic transducer 1220 or the substrate, which can effectively reduce the stiffness of the elastic element 12122, thereby increasing the vibration amplitude of the mass element 12121 during the vibration of the vibration unit 1212, which reduces the resonant frequency of the vibration sensor 1200 and improves the sensitivity of the vibration sensor 1200. In some embodiments, the resonant frequency of the vibration sensor 1200 may be 1000Hz to 4000Hz. Preferably, the resonant frequency of the vibration sensor 1200 may be 1000Hz to 3500Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 1000Hz to 3000Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 1000Hz to 2500Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 1000Hz to 2000Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 1000 Hz to 1500 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 1500 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 2000 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 2500 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 3000 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 3500 Hz to 4000 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 2000 Hz to 3500 Hz. More preferably, the resonant frequency of the vibration sensor 1200 may be 2500 Hz to 3000 Hz.

[0125] In some embodiments, the first elastic portion 122A and the second elastic portion 122B may be made of the same or different materials. As an example only, the materials of the first elastic portion 122A and the second elastic portion 122B may include silicone rubber, silicone gel, silicone sealant, etc. or any combination thereof. In some embodiments, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.1-100HA. Preferably, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.2-95HA. More preferably, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.3-90HA. More preferably, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.4-85HA. More preferably, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.5-80HA. More preferably, the Shore hardness of the first elastic portion 122A and the second elastic portion 122B may be 0.6-75HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 0.7-70HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 0.8-65HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 0.9-60HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-55HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-50HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-45HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-40HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-35HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-30HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-25HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-20HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-15HA. More preferably, the first elastic part 122A and the second elastic part 122B may have a Shore hardness of 1-10HA.

[0126] In some embodiments, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 10-300um. Preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 20-280um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 30-260um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 40-240um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 50-240um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 50-220um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 50-200um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 60-180um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 70-160um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 80-140um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 90-120um. More preferably, the thickness of the first elastic portion 122A along the vibration direction of the mass element 12121 is 100-110um.

[0127] In some embodiments, the length of the first elastic portion 122A in a direction perpendicular to the vibration direction of the mass element 12121 (i.e., the width from one side close to the mass element 12121 to the other side away from the mass element 12121) is 10-300um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 20-280um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 30-260um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 40-240um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-240um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-220um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-200um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 60-180um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 70-160um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 80-140um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 90-120um. In some embodiments, the width of the first elastic portion 122A from one side close to the mass element 12121 to the other side away from the mass element 12121 is 100-110um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 20-280um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 30-260um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 40-240um.In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-240um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-220um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 50-200um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 60-180um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 70-160um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 80-140 um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 90-120 um. In some embodiments, the width of the second elastic portion 122B from one side close to the mass element 12121 to the other side away from the mass element 12121 is 100-110 um.

[0128] It should be noted that the above Fig.11 The description of the vibration sensor 1200 and its components is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the vibration sensor 1200 under the guidance of this specification. For example, the housing 1211 and the acoustic transducer 1220 can be in contact (e.g., physically connected) or there is a gap. These modifications and changes are still within the scope of this specification.

[0129] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0130] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0131] In addition, it will be appreciated by those skilled in the art that various aspects of the present application may be illustrated and described by a number of patentable categories or situations, including any new and useful process, machine, product or combination of substances, or any new and useful improvements thereto. Accordingly, various aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may all be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". In addition, various aspects of the present application may be represented as a computer product located in one or more computer-readable media, which includes computer-readable program code.

[0132] A computer storage medium may include a propagated data signal containing computer program code, for example, in baseband or as part of a carrier wave. The propagated signal may be in a variety of forms, including electromagnetic, optical, etc., or a suitable combination. A computer storage medium may be any computer-readable medium other than a computer-readable storage medium, which can be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit the program for use. The program code on the computer storage medium may be transmitted via any suitable medium, including radio, cable, fiber optic cable, RF, or similar media, or any combination of the above media.

[0133] The computer program coding required for the operation of each part of the application can be written in any one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python, etc., conventional procedural programming languages ​​such as C language, Visual Basic, Fortran 2003, Perl, COBOL 2002, PHP, ABAP, dynamic programming languages ​​such as Python, Ruby and Groovy, or other programming languages, etc. The program coding can be run completely on the user's computer, or run on the user's computer as an independent software package, or run partly on the user's computer and partly on the remote computer, or run completely on the remote computer or server. In the latter case, the remote computer can be connected to the user's computer through any network form, such as a local area network (LAN) or a wide area network (WAN), or connected to an external computer (e.g., via the Internet), or in a cloud computing environment, or used as a service such as software as a service (SaaS).

[0134] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences described in this application, the use of alphanumeric characters, or the use of other names are not intended to limit the order of the processes and methods of this application. Although the above disclosure discusses some invention embodiments that are currently considered useful through various examples, it should be understood that such details are only for illustrative purposes, and the attached claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of this application. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.

[0135] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0136] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0137] Each patent, patent application, patent application disclosure, and other materials, such as articles, books, instructions, publications, documents, etc., cited in this application are hereby incorporated by reference in their entirety. Except for application history documents that are inconsistent with or conflicting with the content of this application, documents that limit the broadest scope of the claims of this application (currently or later attached to this application) are also excluded. It should be noted that if the descriptions, definitions, and / or use of terms in the attached materials of this application are inconsistent or conflicting with the content described in this application, the descriptions, definitions, and / or use of terms in this application shall prevail.

[0138] Finally, it should be understood that the embodiments described in this application are only used to illustrate the principles of the embodiments of the present application. Other variations may also fall within the scope of the present application. Therefore, as an example and not a limitation, the alternative configurations of the embodiments of the present application may be considered to be consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to the embodiments explicitly introduced and described in the present application.

Claims

1. A vibration sensor, characterized in that: include: A vibration receiver, comprising a shell and a vibration unit, wherein the shell forms an acoustic cavity, and the vibration unit is located in the acoustic cavity and separates the acoustic cavity into a first acoustic cavity and a second acoustic cavity; as well as an acoustic transducer in acoustic communication with the first acoustic cavity, wherein: The housing is configured to generate vibration based on an external vibration signal, the vibration unit vibrates in response to the vibration of the housing, and transmits the vibration to the acoustic transducer through the first acoustic cavity to generate an electrical signal, The vibration unit includes a mass element and an elastic element, the deviation between the cross-sectional areas of the mass element and the first acoustic cavity perpendicular to the vibration direction of the mass element is less than 25%, and the elastic element is connected to the side wall of the mass element in a surrounding manner.

2. The vibration sensor according to claim 1, characterized in that: In a frequency range less than 1000 Hz, the sensitivity of the vibration sensor is greater than or equal to -40 dB.

3. The vibration sensor according to claim 1, characterized in that: The elastic element extends toward the acoustic transducer and is directly or indirectly connected to the acoustic transducer.

4. The vibration sensor according to claim 3, characterized in that: The width of the elastic element varies from one side close to the mass element to the other side far from the mass element, and the variation is less than or equal to 300 um.

5. The vibration sensor according to claim 3, characterized in that: The shell is connected to the acoustic transducer, and one end of the elastic element extending toward the acoustic transducer is directly connected to the acoustic transducer.

6. The vibration sensor according to claim 3, characterized in that: The vibration receiver further includes a substrate, which is disposed on the acoustic transducer, and one end of the elastic element extending toward the acoustic transducer is connected to the substrate.

7. The vibration sensor according to claim 6, characterized in that: The substrate comprises a bottom plate and a side wall, the bottom plate is connected to the acoustic transducer, and the inner surface of the side wall is connected to the elastic element.

8. The vibration sensor according to claim 1, characterized in that: The elastic element includes a first elastic portion and a second elastic portion, two ends of the first elastic portion are respectively connected to the side wall of the mass element and the second elastic portion, and the second elastic portion extends toward the acoustic transducer and is directly or indirectly connected to the acoustic transducer.

9. The vibration sensor according to claim 1, characterized in that: A surface of the elastic element away from the acoustic transducer is lower than a surface of the mass element away from the acoustic transducer.

10. The vibration sensor according to claim 1, characterized in that: The volume of the first acoustic cavity is smaller than the volume of the second acoustic cavity.

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