A vibration sensor and assembly method thereof

Abstract

The embodiment of this specification provides a vibration sensor, including: an acoustic transducer, a vibration component, a shell, and a substrate located between the acoustic transducer and the vibration component, the substrate including a base layer and a metal layer sequentially arranged along the vibration direction of the vibration component, the base layer is located between the vibration component and the metal layer, the metal layer has an area not covered by the base layer on a plane perpendicular to the vibration direction of the vibration component, wherein the vibration component is connected to the base layer, and the shell is connected to the area of ​​the metal layer not covered by the base layer. The vibration sensor can improve the overall structural strength of the vibration sensor without increasing the volume of the vibration sensor by connecting the shell to the metal layer of the substrate.

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 international application with application number PCT / CN2021 / 107978 filed on July 22, 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 and an assembly method thereof. 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 current vibration sensor is usually directly equipped with a corresponding vibration component on the basis of an acoustic transducer (for example, an air conduction microphone), and then the shell is directly fixedly connected to the substrate of the acoustic transducer (for example, glued) to seal the vibration component. The structural stability of this vibration sensor is not high, and the shell and the acoustic transducer are easy to fall off. In addition, when the vibration sensor is used as a microelectronic device, its size is limited, and the vibration component itself occupies a large space. At this time, the direct connection of the shell to the substrate (for example, glued) will limit the size of the vibration component and affect the performance of the vibration sensor (for example, sensitivity).

[0005] Therefore, it is desired to provide a vibration sensor with high structural stability and high sensitivity and an assembly method of the vibration sensor. Summary of the invention

[0006] One of the embodiments of the present specification provides a vibration sensor, comprising: an acoustic transducer; a vibration component, configured to generate an air conduction signal in response to an external vibration signal and transmit it to the acoustic transducer to generate an electrical signal; a shell, configured to accommodate the vibration component; and a substrate located between the acoustic transducer and the vibration component, the substrate comprising a base layer and a metal layer arranged in sequence along the vibration direction of the vibration component, the base layer being located between the vibration component and the metal layer, the metal layer having an area not covered by the base layer on a plane perpendicular to the vibration direction of the vibration component, wherein the vibration component is connected to the base layer, and the shell is connected to the area of ​​the metal layer not covered by the base layer.

[0007] One of the embodiments of the present specification provides an assembly method of a vibration sensor, comprising: placing a mass element on one side of a substrate, the substrate being provided with a sound inlet hole, the sound inlet hole being acoustically connected to an acoustic transducer on the other side of the substrate, and the mass element covering the sound inlet hole; coating a colloid on the side wall of the mass element, heating the colloid at a specific temperature to lift the mass element relative to the substrate; after the colloid is solidified, removing a portion of the colloid away from the mass element, the colloid and the mass element forming a vibration component, in a vibration direction perpendicular to the vibration direction of the vibration component, the substrate has an area not covered by the colloid on a plane perpendicular to the vibration direction of the vibration component; and connecting a shell to the area not covered by the colloid to form the vibration sensor.

[0008] Compared with the prior art, the beneficial effects that may be brought about by the embodiments of this specification include but are not limited to: (1) The substrate provided in the embodiments of this specification includes a base layer and a metal layer, and the metal layer has an area not covered by the base layer on a plane perpendicular to the vibration direction; by connecting the vibration component to the base layer, and connecting the shell to the uncovered area in the metal layer, in this way, there is no need to reserve additional packaging dimensions on the surface of the base layer to fix the shell, so that the size of the mass element (for example, length, width, radius or thickness) can be increased while ensuring a certain volume of the vibration sensor, thereby increasing the mass of the mass element. The larger the mass of the mass element, the more the resonance peak of the vibration sensor will tend toward low frequencies. (1) Since the frequency of vibration signals (e.g., bone conduction sound) is relatively low, the sensitivity of the vibration sensor in a relatively low frequency band (e.g., 20 Hz-6000 Hz) can be improved by increasing the mass of the mass element; (2) the uncovered area of ​​the shell and the metal layer can be connected by welding instead of conventional gluing, which can greatly improve the packaging strength of the vibration sensor; (3) a pressure relief hole is provided on the shell or the elastic element, which can balance the air pressure changes inside the first acoustic cavity and the second acoustic cavity caused by the temperature changes during the preparation process of the vibration sensor (e.g., during the reflow soldering process), thereby reducing or preventing damage to the components of the vibration sensor caused by the air pressure changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 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:

[0010] Figure 1 is a schematic diagram of the structure of a vibration sensor according to some embodiments of this specification;

[0011] Figure 2 is a schematic diagram of the structure of a substrate according to some embodiments of this specification;

[0012] Figure 3 is a schematic diagram of the structure of a mass element and an elastic element according to some embodiments of this specification;

[0013] Figure 4 is a flow chart of a method for assembling a vibration sensor according to some embodiments of this specification;

[0014] Figure 5 is a flowchart of an assembly process of a vibration sensor according to some embodiments of this specification;

[0015] Figure 6 It is a flow chart of the assembly process of the vibration sensor according to some embodiments of the present specification. DETAILED DESCRIPTION

[0016] 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.

[0017] 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.

[0018] 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 "comprise" and "include" 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.

[0019] 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.

[0020] The present specification describes a vibration sensor. In some embodiments, the vibration sensor may include a housing, a vibration assembly, an acoustic transducer, and a substrate disposed between the acoustic transducer and the vibration assembly, and the substrate may be used to fix and / or support other components (e.g., housing, vibration assembly, etc.) in the vibration sensor. In some embodiments, the substrate may be a side wall of the acoustic transducer, or may be an independent structure relative to the acoustic transducer. In some embodiments, the substrate may have a multilayer structure, for example, the substrate may include a base layer and a metal layer sequentially disposed along the vibration direction of the vibration assembly. Optionally, the base layer is located between the vibration assembly and the metal layer. In some embodiments, the metal layer has an area not covered by the base layer on a plane perpendicular to the vibration direction. By connecting the vibration assembly to the base layer, and connecting the housing to the uncovered area in the metal layer, the vibration assembly and the housing are located on different structural layers (e.g., base layer and metal layer) of the substrate, so that the surface of the base layer does not need to leave additional packaging dimensions to fix the housing, so that the size of the mass element (e.g., length, width, radius or thickness) can be increased under the premise of ensuring a certain volume of the vibration sensor, thereby increasing the mass of the mass element. The greater the mass of the mass element, the resonance peak of the vibration sensor will move toward low frequency. Since the frequency of vibration signals (e.g., bone conduction sound) is relatively low, the sensitivity of the vibration sensor in a relatively low frequency band (e.g., 20 Hz-6000 Hz) can be improved by increasing the mass of the mass element. In addition, the housing and the uncovered area of ​​the metal layer can be connected by welding, instead of the conventional adhesive connection method, which can greatly improve the packaging strength of the vibration sensor.

[0021] The sensor provided in the embodiments of this specification will be described in detail below with reference to the accompanying drawings.

[0022] Figure 1 It is a schematic diagram of the structure shown in some embodiments of this specification. Figure 1 As shown, the vibration sensor 100 may include an acoustic transducer 110 , a vibration assembly 120 , and a housing 130 .

[0023] The vibration sensor 100 can convert the external vibration signal into an electrical signal. In some embodiments, the external vibration signal may include a vibration signal when a person speaks, a vibration signal generated by the skin moving with the human body or by a speaker close to the skin, and a vibration signal generated by an object or air in contact with the vibration sensor 100, or any combination thereof. Further, the electrical signal generated by the vibration sensor can be input into an external electronic device. In some embodiments, the external electronic device may include a mobile device, a wearable device, a virtual reality device, an augmented reality device, or the like, 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, or the like, 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, a smart clothing, a smart backpack, a smart accessory, or the like, 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, or the like, 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.

[0024] In some embodiments, the vibration sensor 100 may further include a substrate 140 located between the vibration assembly 120 and the acoustic transducer 110. In some embodiments, the substrate 140 may be used to support and / or fix other components in the vibration sensor 100 (e.g., the vibration assembly 120, the housing 130, etc.), and the vibration assembly 120 and / or the housing 130 may be connected to the acoustic transducer 110 through the substrate 140. In some embodiments, the substrate 140 may be a part of the acoustic transducer 110. For example, the substrate 140 may form a side wall of the acoustic transducer 110. By such an arrangement, the vibration assembly 120, the housing 130, and / or the acoustic transducer 110 may be processed and produced as independent components, and then further assembled to form the vibration sensor 100. The acoustic transducer 110 with the substrate can be directly physically connected (e.g., glued) to the vibration assembly 120 and the housing 130 to obtain the vibration sensor 100. In some embodiments, the substrate 140 may also be an independent structure relative to the acoustic transducer 110, and the substrate 140 is connected to the acoustic transducer 110. For example, the vibration assembly 120, the housing 130 and the acoustic transducer 110 may be connected to the upper and lower surfaces of the substrate 140, respectively. In some embodiments, the connection method between the vibration assembly 120 and / or the housing 130 and the acoustic transducer 110 and the substrate 140 may include but is not limited to bonding (for example, connected by epoxy resin), welding, clamping or integral molding, etc. In some embodiments, the material of the substrate 140 may include metal (for example, iron, copper, stainless steel, etc.), alloy, non-metal (plastic, rubber, resin), etc. or any combination thereof. In some embodiments, the substrate 140 may be a single structural layer. For example, the substrate 140 includes only one metal layer or a non-metal layer. In some embodiments, the substrate 140 may be a composite structural layer, for example, the substrate 140 may include a base layer (for example, base layer 141) for connecting the vibration assembly 120 and a metal layer (for example, metal layer 142) for connecting the housing 130. More description about the substrate 140 can be found elsewhere in this specification, for example, Figure 2 and its related description.

[0025] In some embodiments, the housing 130 may be a structure having a storage space inside, one end of the housing 130 is an open end, and the open end of the housing 130 is connected to the substrate 140 to form a packaging structure having an acoustic cavity, and the vibration assembly 120 may be located in the acoustic cavity. In some embodiments, the shape of the housing 130 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 assembly 120) disposed in the housing. In some embodiments, the vibration assembly 120 may separate the acoustic cavity formed by the housing 130 into a first acoustic cavity 131 and a second acoustic cavity 132. The substrate 140 may include one or more sound inlet holes 143, the sound inlet holes 143 run through the substrate 140, and the first acoustic cavity 131 may be acoustically connected to the acoustic transducer 110 through the sound inlet holes 143.

[0026] In some embodiments, the vibration component 120 may include an elastic element 121 and a mass element 122. The elastic element 121 may be connected to the side wall of the mass element 122. The elastic element 121 extends toward the substrate 140 and is connected to the substrate 140. It should be noted that the vibration component 120 is not limited to Figure 1 The elastic element 121 and mass element 122 shown may also be other structures, and any structure that can generate vibration based on the vibration of the shell 130 may be regarded as the vibration component 120. For example, in some embodiments, the elastic element may be a membrane structure, and the mass element is located on one or both sides of the membrane structure. The membrane structure is connected to the shell around the membrane structure, or the membrane structure is connected to the substrate, or the membrane structure is connected to the substrate through a connector. For another example, in some embodiments, the elastic element may not be arranged around the side wall of the mass element, one end of the elastic element is connected to one side of the mass element, and the other end of the elastic element is connected to the substrate. Further, the external vibration signal may be transmitted to the vibration component 120 through the shell 130, and the mass element 122 in the vibration component 120 vibrates in response to the vibration of the shell 130 driven by the elastic element 121. When the mass element 122 vibrates, the mass element 122 is deformed, thereby causing a volume change in the first acoustic cavity 131, and the change is converted into a sound pressure change in the cavity (or called an air conduction signal). For specific details about the vibration component 120, please refer to Figure 3 and its related description.

[0027] When the vibration sensor 100 is working, the housing 130 can generate vibrations based on an external vibration signal. The vibration assembly 120 can vibrate in response to the vibration of the housing 130 to generate an air conduction signal, which can be transmitted to the acoustic transducer 110 through the first acoustic cavity 131 to generate an electrical signal. Specifically, the acoustic transducer 110 can detect the sound pressure change in the first acoustic cavity 131 and generate an electrical signal based on this. In some embodiments, the acoustic transducer 110 may include a diaphragm (not shown in the figure), and the diaphragm may be arranged at a position corresponding to the sound inlet hole 143. The sound pressure change in the first acoustic cavity 131 can pass through the sound inlet hole 143 and act on the diaphragm, causing the diaphragm to vibrate (or deform), and the acoustic transducer 110 (for example, the magnetic circuit system in the acoustic transducer 110) can convert the vibration of the diaphragm into an electrical signal.

[0028] 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 110, etc. These modifications and changes are still within the scope of this specification.

[0029] Figure 2 Schematic diagram of the structure of the substrate according to some embodiments of the present specification. Figure 1 and Figure 2 , the substrate 140 may include a base layer 141 and a metal layer 142 arranged in sequence along the vibration direction of the vibration component 120. Among them, the base layer 141 is located in the middle area of ​​the metal layer 142, and in the vibration direction perpendicular to the vibration component 120, there is a spacing d between the side wall of the metal layer 142 and the side wall of the base layer 141, which means that the metal layer 142 has an area not covered by the base layer 141 on the plane perpendicular to the vibration direction of the vibration component 120, for connecting the housing 130. The side wall of the metal layer 142 refers to the side wall of the metal layer 142 parallel to the vibration direction of the vibration component 120. The side wall of the base layer 141 refers to the side wall of the base layer 141 parallel to the vibration direction of the vibration component 120. In some embodiments, the material of the base layer 141 may include non-metallic materials such as ink, plastic, rubber, resin, etc. In some embodiments, the material of the metal layer 142 may include metal materials or alloy materials such as iron, copper, stainless steel, etc. It should be noted that the substrate 140 is not limited to the base layer 141 and the metal layer 142, but may also include other layered structures. The other layered structures may be located on the upper surface of the base layer 141, between the base layer 141 and the metal layer 142, or on the lower surface of the metal layer 142.

[0030] In some embodiments, in order to ensure that the housing 130 can be adapted to the metal layer 142, the area of ​​the metal layer 142 not covered by the base layer 141 is sufficient to connect the housing 130 and the metal layer 142, that is, the size of the spacing d can be greater than or equal to the shell thickness of the housing 130. In some embodiments, the size of the spacing d can be 0.05mm to 5mm. While ensuring the area of ​​the area where the metal layer 142 is not covered by the base layer 141, in order to reduce the area of ​​the metal layer not covered by the base layer 141 to save the material for making the metal layer, in some embodiments, the size of the spacing d can be 0.1mm to 4mm. In order to facilitate the packaging of the vibration sensor 100 and make the assembly more compact, in some embodiments, the size of the spacing d can be 1mm to 3mm. It should be noted that the spacing d is not limited to the above range, and the size of the spacing d can be adaptively adjusted according to the shape of the housing 130 and the wall thickness of its open end. In some embodiments, the housing 130 and the metal layer 142 can be connected by welding. After the welding between the housing 130 and the metal layer 142 is completed, a welding layer composed of welding material (e.g., solder) exists between the housing 130 and the metal layer 142. By connecting the housing 130 and the metal layer 142 by welding, the connection strength between the housing and the metal layer 142 can be improved, thereby improving the packaging strength of the vibration sensor 100 and ensuring the reliability of its structure. In other embodiments, the housing 130 can also be directly connected to the base layer 141 of the substrate 140.

[0031] In some embodiments, the thickness of the base layer 141 may be related to the type of the acoustic transducer 110. In some embodiments, the thickness of the base layer 141 may be 0.05 mm to 1 mm. Preferably, the thickness of the base layer 141 may be 0.1 mm to 0.8 mm. More preferably, the thickness of the base layer 141 may be 0.1 mm to 0.4 mm.

[0032] Figure 3 Schematic diagram of the structure of the mass element and the elastic element according to some embodiments of this specification. Figure 1 and Figure 3As shown, the vibration component 120 may include an elastic element 121 and a mass element 122. The mass element 122 is connected to the elastic element 121, and the elastic element 121 is connected to the base layer 141 of the substrate 140. In some embodiments, the elastic element 121 may be connected to the mass element 122 and the base layer 141, respectively, by physical connection (e.g., gluing). In some embodiments, the elastic element 121 may be a solid material with a certain viscosity, directly bonded to the mass element 122 and the base layer 141, respectively. In some embodiments, the elastic element 121 may be obtained by applying a fluid material with a certain viscosity on the base layer 141 and / or the mass element 122, and then curing and molding it. For how to cure and mold the elastic element 121, please refer to other places in this specification (e.g., Figure 4 ). In some embodiments, the elastic element 121 may be a material having good elasticity (i.e., easily elastically deformed), so that the vibration assembly 120 may vibrate in response to the vibration of the housing 130. As an example only, the material of the elastic element 121 may include silicone rubber, silicone gel, silicone sealant, foam, etc., or any combination thereof.

[0033] The mass element 122 may also be referred to as a mass block. In some embodiments, the material of the mass element 122 may be a material having a density greater than a certain density threshold (e.g., 6 g / cm3), such as a metal. As an example only, the material of the mass element 122 may include lead, copper, silver, tin, stainless steel, alloys, etc., or any combination thereof.

[0034] In some embodiments, the mass element 122 and the elastic element 121 may be made of different materials and assembled (e.g., glued) together to form the vibration assembly 120. In some embodiments, the mass element 122 and the elastic element 121 may also be made of the same material and formed into an integral part to form the vibration assembly 120.

[0035] In some embodiments, the elastic element 121 may be connected to the side wall of the mass element 122 around the elastic element 121. Figure 3As shown, the inner side of the elastic element 121 is connected to the side wall of the mass element 122. The inner side of the elastic element 121 may refer to the side where the space surrounded by the elastic element 121 is located. The side wall of the mass element 122 may refer to the side of the mass element 122 that is parallel to the vibration direction. The upper and lower surfaces of the mass element 122 are approximately perpendicular to the vibration direction, and are used to define the second acoustic cavity 132 and the first acoustic cavity 131, respectively. During the preparation of the vibration sensor, the elastic element 121 is first coated on the side wall of the mass element 122 as an elastic colloid. Under high temperature conditions, the air pressure inside the vibration sensor increases, and the mass element 122 is lifted relative to the substrate 140 under the action of the air pressure. At this time, the colloid is deformed under the drive of the mass element 122, and the colloid is solidified to form Figure 1 As shown in the elastic element 121, during the deformation process, the width of the elastic element 121 along the vibration direction of the vertical vibration component 120 will be very thin, so that the elastic element 121 has a lower elastic coefficient, which reduces the resonant frequency of the vibration sensor 100, thereby increasing the vibration amplitude of the mass element 122 during the vibration of the vibration component 120, and improving the sensitivity of the vibration sensor 100.

[0036] In some embodiments, the shape of the elastic element 121 may be adapted to the shape of the mass element 122. For example, the elastic element 121 may be a tubular structure, and the open end of the tubular structure has the same cross-sectional shape as the mass element 122 in the cross section perpendicular to the vibration direction of the mass element 122. The open end of the elastic element 121 may be an end connected to the mass element 122. Figure 3 As shown, the shape of the mass element 122 on the cross section perpendicular to the vibration direction of the mass element 122 is a quadrilateral, and the area surrounded by the elastic element 121 is a tube, and the tube has a quadrilateral hole on the cross section perpendicular to the vibration direction of the mass element 122. As an example only, the shape of the mass element 122 on the cross section perpendicular to the vibration direction of the mass element 122 may also include regular shapes (for example, circular, elliptical, fan-shaped, rounded rectangular, polygonal) and irregular shapes, etc. Correspondingly, the shape of the tube surrounded by the elastic element 121 on the cross section perpendicular to the vibration direction of the mass element 122 may include a tube with a regular or irregular shaped aperture. This specification does not limit the shape of the outer side of the tubular elastic element 121. The outer side of the elastic element 121 may be the side opposite to the inner side of the elastic element 121. For example, the shape of the outer side of the tubular elastic element 121 may include a cylindrical, elliptical cylindrical, conical, rounded rectangular cylindrical, rectangular cylindrical, polygonal cylindrical, irregular cylindrical, etc. or any combination thereof. As Figure 3 As shown, the outer side of the tubular elastic element 121 may be in the shape of a quadrilateral.

[0037] In some embodiments, at least one pressure relief hole 151 may be provided on the mass element 122. The pressure relief hole 151 may penetrate the mass element 122. The pressure relief hole 151 on the mass element 122 allows the gas in the first acoustic cavity 131 and the second acoustic cavity 132 to circulate, thereby balancing the pressure changes inside the first acoustic cavity 131 and the second acoustic cavity 132 caused by the temperature changes during the preparation process of the vibration sensor 100 (for example, during the reflow process), and reducing or preventing the damage to the components of the vibration sensor 100 caused by the pressure changes, such as cracking, deformation, etc. In some embodiments, at least one pressure relief hole 151 may also be provided on the shell 130. When the mass element 122 vibrates, the pressure relief hole 151 on the shell 130 can connect the second acoustic cavity 132 with the external environment, reducing the damping of the air in the second acoustic cavity 132 on the vibration of the mass element 122.

[0038] In some embodiments, the pressure relief hole 151 on the housing 130 and / or the mass element 122 may be a single hole. In order to reduce the resistance of the gas inside the second acoustic cavity 132 to the vibration of the vibration component, in some embodiments, the diameter of the single hole may be greater than 1um. In order to prevent the size of the single hole from being too large, affecting the air pressure changes inside the first acoustic cavity 131 and the second acoustic cavity 132, so as to affect the sensitivity of the vibration sensor 100, in some embodiments, the diameter of the single hole may be less than 50um. In order to reduce the resistance of the gas inside the second acoustic cavity 214 to the vibration of the vibration component 212, while ensuring the sensitivity of the vibration sensor 200, in some embodiments, the diameter of the single hole may be 2-45um. In some embodiments, in order to further facilitate processing, the diameter of the single hole may be 3-40um. More preferably, the diameter of the single hole may be 7-10um. In some embodiments, the pressure relief hole 151 may be an array consisting of a certain number of micropores. As an example only, the number of micropores may be 2-10. In order to reduce the resistance of the gas inside the second acoustic cavity 132 to the vibration of the vibration component, in some embodiments, the diameter of each micropore may be greater than 0.1um. In order to prevent the size of the pressure relief hole 151 from being too large, affecting the air pressure changes inside the first acoustic cavity 131 and the second acoustic cavity 132, so as to affect the sensitivity of the vibration sensor 100, in some embodiments, the diameter of each micropore may be less than 25um. In order to reduce the resistance of the gas inside the second acoustic cavity 132 to the vibration of the vibration component, while ensuring the sensitivity of the vibration sensor 100, in some embodiments, the diameter of each micropore may be 0.5-20um. In some embodiments, in order to further facilitate processing, the diameter of each micropore may be 0.5-15um.

[0039] In some embodiments, air-conducted sound in the environment may affect the performance of the vibration sensor 100. In order to reduce the influence of air-conducted sound in the environment, after the vibration sensor 100 is prepared, for example, after reflow soldering, a sealing material may be used to seal the at least one pressure relief hole 151 on the housing 130. As an example only, the sealing material may include epoxy glue, silicon sealant, etc. or any combination thereof.

[0040] In some embodiments, the housing 130 and the mass element 122 may not be provided with the pressure relief hole 151. In some embodiments, when the housing 130 and the mass element 122 are not provided with the pressure relief hole 151, the components of the vibration sensor 100 may be prevented from being damaged due to the change in air pressure inside the first acoustic cavity 131 and the second acoustic cavity 132 by improving the connection strength between the components of the vibration sensor 100 (for example, increasing the connection strength of the glue connecting the components).

[0041] The embodiments of this specification also provide a method for assembling a vibration sensor, which can be applied to the vibration sensor described in the embodiments of this specification. The method mainly involves coating the side wall of the mass element with colloid, and then heat-treating the colloid to lift the mass element relative to the substrate. After the colloid is solidified, the portion of the colloid away from the mass element is removed, so that the remaining colloid and the mass element form a vibration component. At the same time, in the vibration direction perpendicular to the vibration direction of the vibration component, the substrate has an area not covered by the colloid on a plane perpendicular to the vibration direction of the vibration component. The housing is connected to the area of ​​the substrate not covered by the colloid to form a vibration sensor.

[0042] The following will be combined Figure 1 The vibration sensor 100 shown in the figure describes in detail the assembly method of the vibration sensor described in some embodiments of this specification. However, it should be noted that the method is not only applicable to the vibration sensor whose substrate 140 includes a base layer 141 and a metal layer 142, but also applicable to the vibration sensor whose substrate 140 is a single structural layer.

[0043] Figure 4 is a flow chart of a method for assembling a vibration sensor according to some embodiments of the present specification. Figure 5-6 It is a schematic diagram of the structure of a vibration sensor during the assembly process according to some embodiments of the present specification.

[0044] like Figure 4 As shown, the vibration sensor assembly method 400 may include the following steps:

[0045] Step 410 , placing a mass element on one side of a substrate, a sound inlet hole is provided on the substrate, the sound inlet hole is acoustically connected to an acoustic transducer on the other side of the substrate, and the mass element covers the sound inlet hole.

[0046] In the above step 410, after the substrate is connected to the acoustic transducer, the mass block is placed on the side of the substrate away from the acoustic transducer. The substrate is provided with a sound inlet hole, which is opened before the mass block is placed on the substrate, or the substrate itself has a sound inlet hole, which is acoustically connected to the acoustic transducer on the other side of the substrate, and the mass element covers the sound inlet hole. In some embodiments, the number of the sound inlet holes can be one or more.

[0047] Step 420 , after applying colloid on the sidewall of the mass element, the colloid is heated at a specific temperature to lift the mass element relative to the substrate.

[0048] Specifically, after the colloid is coated on the side wall of the mass element, a closed space is formed between the mass element and the substrate. When the colloid is heated at a specific temperature, the gas inside the acoustic transducer (for example, air, nitrogen, helium, etc.) expands due to heat. At this time, the gas expanded by heat will act on the mass element and lift the mass element relative to the substrate. Since the colloid on the side wall of the mass element is elastic, the mass element will drive the colloid to deform while lifting, so that the colloid forms a tubular structure. The deformed colloid (i.e., the tubular structure) forms a first acoustic cavity with the mass element and the substrate. In some embodiments, the volume of the first acoustic cavity can be controlled by controlling the lifting height of the mass element. In some embodiments, a limiting jig can be set above the mass element. When the colloid is heated at a specific temperature, the colloid can expand due to heat until the side of the mass element away from the substrate is lifted to the limiting jig. By setting a limiting jig, the height of the mass element lifting can be effectively limited, thereby accurately controlling the volume of the first acoustic cavity. In addition, the limiting jig can control the expansion height of the elastic element in the vibration direction so that the side of the elastic element facing away from the substrate is parallel or approximately parallel to the substrate, thereby preventing the mass element from tilting relative to the substrate, so that the upper side or lower side of the mass element is parallel or approximately parallel to the substrate.

[0049] In some embodiments, in order to ensure that the colloid maintains its performance during the heat treatment, for example, its viscosity or elastic coefficient will not change significantly, the specific temperature for heating the colloid can be 50° to 250°. In some embodiments, the specific temperature for heating the colloid can be 50° to 200°. In some embodiments, in order to control the lifting of the mass element at an appropriate speed, and after contacting the limiting jig, the expansion height of the elastic element in the vibration direction can be controlled, so that the side of the elastic element away from the substrate is parallel or approximately parallel to the substrate, thereby preventing the mass element from tilting relative to the substrate, so that the upper side or lower side of the mass element is parallel or approximately parallel to the substrate, the specific temperature for heating the colloid can be 10° to 200°.

[0050] In order to ensure that the colloid can support the mass element during the heating process, in some embodiments, the width of the colloid coated on the side wall of the mass element may be greater than 0.1mm. In order to facilitate the lifting of the mass element during the heating process and subsequent processing, in some embodiments, the width of the colloid coated on the side wall of the mass element may be less than 5mm. In order to ensure that the colloid can support the mass element during the heating process, and at the same time facilitate the lifting of the mass element during the heating process and subsequent processing, in some embodiments, the width of the colloid may be 0.1mm to 2mm. Preferably, the width of the colloid may be 0.1mm to 0.5mm. Among them, the width of the colloid may refer to the distance of the colloid from one side close to the mass element to the other side away from the mass element.

[0051] Step 430, after the colloid is solidified, the part of the colloid away from the mass element is removed, and the colloid and the mass element form a vibration component. The substrate has an area not covered by the colloid on a plane perpendicular to the vibration direction of the vibration component.

[0052] Specifically, when the mass element is lifted to the position limiting jig, the colloid semi-solidifies or solidifies to form a structure of a specific shape. Depending on the material of the selected colloid, the colloid can complete the solidified state during the heating process, or it can form a semi-solidified state during the heating process, and then further form the solidified state after cooling at room temperature or low temperature, thereby supporting the mass element. In addition, the solidified colloid has a certain elasticity and acts as an elastic element. In some embodiments, the part of the colloid away from the mass element can be removed by laser ablation. In some embodiments, the part of the colloid away from the mass element can also be removed by mechanical contact processing (for example, a milling cutter or a grinder, etc.). By removing part of the colloid, subsequent packaging can be facilitated, and the connection between the shell and the substrate can be achieved without increasing the size of the substrate, thereby reducing the volume of the vibration sensor and improving the aesthetics of the vibration sensor. In addition, by removing part of the colloid, the elastic coefficient of the elastic element can also be adjusted, thereby improving the sensitivity of the vibration sensor.

[0053] Step 440 , connecting the housing to the uncovered area to form a vibration sensor.

[0054] In some embodiments, in order to ensure that the connection between the housing and the uncovered area has a good connection strength, the substrate may be a composite structure layer. For example, the substrate includes a base layer and a metal layer that are located from far to near the acoustic transducer along the vibration direction of the vibration component (for example, Figure 2The base layer 141 and the metal layer 142 shown in the figure), the uncovered area may be the area where the surface of the metal layer away from the acoustic transducer is not covered by the colloid and the base layer. Furthermore, the shell and the metal layer can be connected by welding, so as to enhance the connection strength between the shell and the acoustic transducer. Therefore, when the substrate includes a base layer and a metal layer, in step 430, in addition to removing the part of the colloid away from the mass element, it is also necessary to remove the base layer corresponding to the area not covered by the colloid to expose the metal layer. In some embodiments, the uncovered area may also be the area in the base layer of the substrate that is not covered by the colloid. In this case, the shell can be connected to the area in the base layer that is not covered by the colloid.

[0055] It should be noted that the removal of the portion of the colloid away from the mass element and the removal of the corresponding base layer can be performed at the same time, that is, the base layer corresponding to the portion of the colloid away from the mass element can be removed when the portion of the colloid away from the mass element is removed, or the base layer corresponding to the area not covered by the colloid can be removed after the portion of the colloid away from the mass element is removed.

[0056] In some embodiments, the substrate may be a single structural layer, and the uncovered area may be an area of ​​the surface of the substrate away from the acoustic transducer that is not covered by the colloid. In some embodiments, the housing and the uncovered area may be connected by bonding, clamping, welding, etc.

[0057] It should be noted that the above description of process 400 is only for example and illustration, and does not limit the scope of application of the present application. For those skilled in the art, various modifications and changes can be made to process 400 under the guidance of the present application. However, these modifications and changes are still within the scope of the present application. For example, step 410 and step 420 can be combined.

[0058] The following will describe the assembly of the vibration sensor in detail in conjunction with the vibration sensor assembly process flow chart. Figure 1 The assembly of the vibration sensor 100 is shown as described.

[0059] Figure 5 and Figure 6 is a flowchart of the assembly process of the vibration sensor according to some embodiments of this specification. Figure 5 The AC structure in and the DF structure in 6 can correspond to Figure 4 One or more steps in method 400 are shown.

[0060] Figure 5The structure A in the figure can correspond to step 410 and step 420, that is, when assembling the vibration sensor, the structure A can be obtained after step 410 and step 420 are performed in sequence. Specifically, the mass element 122 is placed on the side of the substrate 140 away from the acoustic transducer 110, and the substrate 140 is provided with a sound inlet hole 143. The sound inlet hole 143 is acoustically connected to the acoustic transducer 110 on the other side of the substrate 140. The mass element 122 covers the sound inlet hole 143, and the colloid 150 is coated on the side wall of the mass element 122. At the same time, the colloid is also in contact with the substrate 140, and a closed space is formed between the mass element 122 and the substrate 140. When the colloid is heated at a specific temperature, the acoustic transducer The gas (for example, air, nitrogen, helium, etc.) inside the device 110 expands due to heat. At this time, the gas that expands due to heat will act on the mass element 122 and cause the mass element 122 to rise relative to the substrate 140. Since the colloid 150 on the side wall of the mass element 122 is elastic, the mass element 122 will cause the colloid to deform while being lifted, so that the colloid 150 forms a tubular structure. The deformed colloid 150 (i.e., the tubular structure) forms a first acoustic cavity with the mass element 122 and the substrate 140.

[0061] Figure 5 The B structure in the figure may correspond to step 430, that is, after performing steps 410 and 420 on the A structure, the B structure may be obtained by performing step 430 based on the A structure. Specifically, as shown in the B structure, after removing the portion of the colloid 150 away from the mass element 122, the base layer 141 has an area not covered by the colloid 150, and the remaining portion of the colloid 150 serves as the elastic element 121 and the mass element 122 to form the vibration assembly 120. In some embodiments, after removing the portion of the colloid 150 away from the mass element 122, a portion of the structure of the area in the base layer 141 not covered by the colloid 150 may be removed, so that the side wall of the base layer 141 forms an approximately step-like structure ( Figure 5 122), so as to facilitate the subsequent installation of the housing 130. It should be noted that in the process of obtaining the B structure, the removal of the corresponding parts of the colloid 150 and / or the base layer 141 can be performed simultaneously or separately. For example, the part of the colloid 150 away from the mass element 122 can be removed first, and then the part of the base layer 141 corresponding to the removed part of the colloid 150 can be removed. In some embodiments, when the substrate 140 is a single structural layer, after removing the part of the colloid 150 away from the mass element 122, the next step, i.e., step 440, can be performed with the obtained structure.

[0062] Figure 5The C structure in the figure may correspond to step 440, that is, after executing step 440 on structure B, structure C may be obtained by executing step 440 based on structure B, and structure C is the assembled vibration sensor 100. Specifically, as shown in structure C, on the basis of structure B, the shell 130 and the area on the base layer 141 that is not covered by the colloid 150 are connected together to form the vibration sensor 100. Among them, the shell 130 and the area on the base layer 141 that is not covered by the colloid 150 may be connected together by welding or gluing. It should be noted that in the substrate 140 before assembly, the base layer 141 and the metal layer 142 are not limited to Figure 5 In some embodiments, the size of the base layer 141 in the vibration direction of the vertical vibration component can be larger than the size of the metal layer in the vibration direction of the vertical vibration component. For example, the outer edge of the base layer 141 extends a certain size (for example, 0.05 mm) relative to the outer edge of the metal layer 142, so that the base layer 141 can fully cover the metal layer 142 to prevent the electronic components on the metal layer 142 from being damaged.

[0063] In some embodiments, during the execution of steps 410 and 420, the width of the colloid 150 (for example, the width from the side of the colloid 150 away from the mass element 122 to the side close to the mass element 122) can meet certain requirements to ensure that the colloid 150 can be used as the elastic element 121 and the mass element 122 to form the vibration component 120 without being removed, and the base layer 141 has an area not covered by the colloid 150 on a plane perpendicular to the vibration direction of the vibration component 120, or there is a certain distance between the side wall of the colloid 150 and the side wall of the substrate 140, that is, Figure 6 The structure D is shown.

[0064] Further, step 430 can be performed based on the D structure to obtain Figure 6 Specifically, in step 430, only the area of ​​the base layer 141 not covered by the colloid 150 (or the mass element 122) needs to be cut off to expose the metal layer 142 and obtain the E structure. Figure 5 The structure of B is similar to that shown in FIG. 1 , so for more information about the structure of E, please refer to the description of Figure 5 Related description of the B structure in .

[0065] Further, step 440 can be performed based on the E structure to obtain Figure 6 For the description of executing step 440 based on the E structure to obtain the F structure, please refer to Figure 5 The relevant description of the C structure can be obtained by executing step 440 based on the B structure, which will not be repeated here.

[0066] In some embodiments, the substrate 140 can be customized before assembly so that the base layer 141 does not completely cover the metal layer 142, and the spacing between the side walls of the base layer 141 and the side walls of the metal layer 142 meets the requirements. In this way, there is no need to cut off the base layer 141 when assembling the vibration sensor, thereby simplifying the assembly operation of the vibration sensor.

[0067] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or a combination of the above, or any other beneficial effects that may be obtained.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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: Acoustic transducer; a vibration assembly configured to generate an air conduction signal in response to an external vibration signal and transmit the air conduction signal to the acoustic transducer to generate an electrical signal; a housing configured to accommodate the vibration assembly; as well as A substrate located between the acoustic transducer and the vibration component, the substrate comprising a base layer and a metal layer sequentially arranged along the vibration direction of the vibration component, the base layer being located between the vibration component and the metal layer, the base layer being located in a middle region of the metal layer, and the metal layer having a region not covered by the base layer on a plane perpendicular to the vibration direction of the vibration component, Wherein, the vibration component is connected to the base layer, and the shell is connected to the area of ​​the metal layer that is not covered by the base layer.

2. The vibration sensor according to claim 1, characterized in that: In a vibration direction perpendicular to the vibration component, a distance is provided between a side wall of the metal layer and a side wall of the base layer.

3. The vibration sensor according to claim 2, characterized in that: The size of the spacing is 0.05mm-5mm.

4. The vibration sensor according to claim 1, characterized in that: The shell and the metal layer are connected by welding or gluing.

5. The vibration sensor according to claim 1, characterized in that: The vibration component comprises an elastic element and a mass element, wherein the elastic element is connected to a side wall of the mass element in a surrounding manner, and the elastic element is connected to a base layer of the substrate.

6. The vibration sensor according to claim 1, characterized in that: The thickness of the base layer is 0.05 mm-1 mm.

7. The vibration sensor according to claim 5, characterized in that: The housing or the mass element is provided with a pressure relief hole.

8. A method for assembling a vibration sensor, characterized in that: include: Placing a mass element on one side of a substrate, wherein a sound inlet hole is provided on the substrate, wherein the sound inlet hole is acoustically connected to an acoustic transducer on the other side of the substrate, and the mass element covers the sound inlet hole; After coating the sidewall of the mass element with colloid, the colloid is heated at a specific temperature to lift the mass element relative to the substrate; After the colloid is solidified, the part of the colloid away from the mass element is removed, and the colloid and the mass element form a vibration component, wherein in a vibration direction perpendicular to the vibration component, the substrate has an area not covered by the colloid on a plane perpendicular to the vibration direction of the vibration component; the substrate comprises a base layer and a metal layer sequentially arranged along the vibration direction of the vibration component, and the base layer is located between the vibration component and the metal layer; While or after removing the portion of the colloid away from the mass element: removing the base layer corresponding to the area not covered by the colloid to expose the metal layer; as well as The housing is connected to the area not covered by the colloid to form the vibration sensor.

9. The method according to claim 8, characterized in that include: The shell and the metal layer are connected by welding or gluing.

10. The method according to claim 8, characterized in that The step of heating the acoustic transducer at a specific temperature to lift the mass element relative to the substrate of the acoustic transducer includes: providing a limiting jig above the mass element, and lifting the side of the mass element away from the substrate to the limiting jig.

11. The method according to claim 8, characterized in that The specific temperature is 50°-250°.

12. The method according to claim 8, characterized in that The thickness of the colloid coated on the side wall of the peripheral side of the mass element is smaller than the thickness of the mass element, and the width of the colloid is 0.1 mm-5 mm.

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