Vibration device

Abstract

One or more embodiments herein relate to a vibration device including a mass element, one or more piezoelectric elements configured to generate vibrations based on an electrical signal, and one or more elastic elements, at least one of which is connected to the mass element and the one or more piezoelectric elements, the one or more piezoelectric elements including a ring-shaped structure and configured such that a direction of vibration based on an electrical signal is parallel to an axial direction of the ring-shaped structure.

Description

[Technical field]

[0001] The present application relates to the field of acoustics, and in particular to vibration devices. [Background technology]

[0002] A piezoelectric speaker generally generates vibrations by the inverse piezoelectric effect of a piezoelectric ceramic material and emits sound waves to the outside. Compared with conventional electromagnetic speakers, piezoelectric speakers have the advantages of high electromechanical conversion efficiency, low energy consumption, small volume, and high integration. With the current trend of miniaturization and integration of devices, piezoelectric speakers have a very bright future. However, compared with conventional electromagnetic speakers, piezoelectric speakers have poor low-frequency sound quality due to poor low-frequency response of the piezoelectric acoustic element. In addition, piezoelectric speakers have many vibration modes within the audible range (e.g., 20Hz to 20kHz), so they cannot form a flat frequency response curve. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, there is a need to provide a vibration device that can reduce vibration modes within the audible range while improving low frequency response. [Means for solving the problem]

[0004] A vibration device according to an embodiment of the present specification includes a mass element, one or more piezoelectric elements configured to generate vibrations based on an electrical signal, and one or more elastic elements, at least one of which is connected to the mass element and the one or more piezoelectric elements, wherein the one or more piezoelectric elements include a ring-shaped structure and are configured such that the direction in which they vibrate based on an electrical signal is parallel to an axial direction of the ring-shaped structure.

[0005] In some embodiments, the one or more piezoelectric elements include a first piezoelectric element having one axial end fixed and another axial end connected to the mass element by at least one of the one or more elastic elements.

[0006] In some embodiments, a projection of the mass element along the axis of the first piezoelectric element lies within a projection of the first piezoelectric element along the axis of the first piezoelectric element.

[0007] In some embodiments, the shape of the mass element is annular and the projection of the mass element along the axis of the first piezoelectric element is other than the projection of the mass element along the axis of the first piezoelectric element.

[0008] In some embodiments, a cover plate is provided on a side of the mass element away from the first piezoelectric element along the axis of the first piezoelectric element.

[0009] In some embodiments, the elastic element connecting the mass element and the first piezoelectric element is multiple, the multiple elastic elements being distributed along a circumferential direction of the ring structure.

[0010] In some embodiments, the elastic elements are positioned in the same plane perpendicular to an axial direction of the first piezoelectric element.

[0011] In some embodiments, the projections of the plurality of elastic elements along the axial direction of the first piezoelectric element have at least two axes of symmetry perpendicular to each other.

[0012] In some embodiments, the shape of the one or more elastic elements includes at least one of a broken line, an S-shape, a spline curve shape, a circular arc shape, and a straight line shape.

[0013] In some embodiments, each of the one or more resilient elements has a plurality of curved segments, the curved segments curving in opposite directions.

[0014] In some embodiments, the one or more elastic elements include a first helical structure and a second helical structure connected to the mass element and the one or more piezoelectric elements, respectively, and the first helical structure and the second helical structure have the same axis and opposite helical directions.

[0015] In some embodiments, the one or more piezoelectric elements include a first piezoelectric element including a first ring-shaped structure and a second piezoelectric element including a second ring-shaped structure, the second piezoelectric element being disposed inside the first ring-shaped structure.

[0016] In some embodiments, the first piezoelectric element has one end along the axial direction fixed and the other end connected to the second piezoelectric element by at least one of the one or more elastic elements, a projection of the mass element along the axial direction is within a projection of the second piezoelectric element along the axial direction, and the mass element is connected to the second piezoelectric element by at least another one of the one or more elastic elements.

[0017] In some embodiments, the second piezoelectric element has one end along the axial direction fixed and the other end connected to the first piezoelectric element by at least one of the one or more elastic elements, the shape of the mass element is ring-shaped, a projection of the mass element along the axial direction is other than a projection of the first piezoelectric element along the axial direction, and the mass element is connected to the first piezoelectric element by at least another one of the one or more elastic elements.

[0018] In some embodiments, the shape of the mass element is ring-shaped, the projection of the mass element along the axial direction is between the projections of the first piezoelectric element and the second piezoelectric element along the axial direction, and the mass element is connected to the first piezoelectric element by at least one of the one or more elastic elements and to the second piezoelectric element by at least another of the one or more elastic elements.

[0019] In some embodiments, the first piezoelectric element or the second piezoelectric element has a fixed end along the axial direction.

[0020] In some embodiments, the one or more resilient elements include one or more inner ring resilient elements and one or more outer ring resilient elements having opposite curvature directions.

[0021] In some embodiments, the electrical signals received by the first piezoelectric element and the second piezoelectric element have a phase difference.

[0022] In some embodiments, the phase difference ranges from 45° to 180°.

[0023] In some embodiments, the one or more piezoelectric elements include at least two first piezoelectric elements, the at least two first piezoelectric elements being connected to each other along an axial direction.

[0024] In some embodiments, the mass element is connected to at least two of the first piezoelectric elements by one or more of the elastic elements, respectively.

[0025] In some embodiments, the number of the first piezoelectric elements is two, and the two first piezoelectric elements have opposite changes in displacement along the axial direction during a vibration process.

[0026] In some embodiments, the connecting surfaces of the two first piezoelectric elements are of the same polarity and opposite electrical potential.

[0027] In some embodiments, the connecting surfaces of the two first piezoelectric elements are of opposite polarity and at the same electrical potential.

[0028] In some embodiments, the one or more piezoelectric elements include at least two second piezoelectric elements, the axes of the at least two second piezoelectric elements overlap with the axes of the at least two first piezoelectric elements, the axial projections of the at least two second piezoelectric elements are within the axial projections of the at least two first ring structures, and the at least two second piezoelectric elements are connected to each other along the axial direction.

[0029] In some embodiments, at least two of the second piezoelectric elements are connected to at least two of the first piezoelectric elements by at least one of the one or more elastic elements.

[0030] In some embodiments, the mass element is connected to at least two of the first piezoelectric elements by at least one of the one or more elastic elements, respectively, or the mass element is connected to at least two of the second piezoelectric elements by at least one of the one or more elastic elements, respectively.

[0031] In some embodiments, the mass element is connected to at least two of the first piezoelectric elements and at least two of the second piezoelectric elements by one or more of the elastic elements, respectively.

[0032] In some embodiments, the vibration device further comprises a piezoelectric beam configured to generate vibration along an axial direction of the annular structure based on an electrical signal, the piezoelectric beam being connected to the mass element.

[0033] In some embodiments, the piezoelectric beam includes at least one first piezoelectric sheet and at least one second piezoelectric sheet, the at least one first piezoelectric sheet and the at least one second piezoelectric sheet are respectively disposed on opposite sides of the piezoelectric beam along the axial direction of the ring-shaped structure, and the at least one first piezoelectric sheet and the at least one second piezoelectric sheet have polarization directions set in opposite directions along the axial direction of the ring-shaped structure.

[0034] In some embodiments, the mass element includes a first mass element and a second mass element, the first mass element being connected to a central portion of the piezoelectric beam by at least one of the one or more elastic elements, and second mass elements being connected to both ends of the piezoelectric beam, respectively.

[0035] In some embodiments, at least one of the one or more elastic elements and the mass element resonate to produce a first resonant peak, and the one or more piezoelectric elements resonate to produce a second resonant peak.

[0036] In some embodiments, the frequency range of the first resonant peak is between 50 Hz and 2000 Hz.

[0037] In some embodiments, the frequency range of the first resonant peak is between 50 Hz and 1000 Hz.

[0038] In some embodiments, the frequency range of the second resonant peak is between 1000 Hz and 50000 Hz.

[0039] In some embodiments, the frequency range of the second resonant peak is between 1000 Hz and 20000 Hz.

[0040] In some embodiments, the frequency range of the second resonant peak is between 2000 Hz and 10000 Hz.

[0041] In some embodiments, the frequency ratio of the second resonant peak to the first resonant peak is in the range of 20-200.

[0042] In some embodiments, at least two of the piezoelectric elements are connected to each other such that when the vibration device vibrates, a third resonant peak is generated, the frequency of the third resonant peak being between the frequency of the first resonant peak and the frequency of the second resonant peak.

[0043] In some embodiments, two of the piezoelectric elements are connected by at least one of the elastic elements to form a double ring structure, the double ring structure resonating to generate the third resonance peak.

[0044] The present application will be further illustrated by exemplary embodiments, which are not limiting and in which like numbers refer to like structures, and are illustrated in detail in the drawings. [Brief description of the drawings]

[0045] [Figure 1] FIG. 2 is an exemplary module diagram of a vibration device according to some embodiments of the present disclosure. [Diagram 2] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Diagram 3] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 4A] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 4B] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Diagram 5] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 6] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 7] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 8] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 9] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 10] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 11] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 12] 2 is an exemplary structural diagram of an elastic element according to some embodiments of the present disclosure; [Figure 13A] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 13B] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 14A] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 14B] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 14C] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 14D] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 15A] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 15B] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 16] 2 is an exemplary frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 17] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 18] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 19] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 20A] FIG. 2 is an exemplary circuit diagram of a first piezoelectric element in accordance with some embodiments of the present disclosure. [Figure 20B] FIG. 11 is another exemplary circuit diagram of a first piezoelectric element in accordance with some embodiments of the present disclosure. [Figure 21] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 22] FIG. 2 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. [Figure 23] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. [Figure 24] 1 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] In order to more clearly describe the technical means of the embodiments of the present application, the drawings necessary for the description of the embodiments will be briefly described below. Obviously, the drawings described below are only some of the examples or embodiments of the present application, and those skilled in the art can apply the present application to other similar scenarios based on these drawings without creative efforts. Unless otherwise clear from the language environment or otherwise described, in the drawings, the same symbols indicate the same structures or operations.

[0047] It should be understood that the terms "system," "apparatus," "unit," and / or "module" used herein are ways to distinguish between various assemblies, elements, components, parts, or assemblies at different levels, however, other terms may be used in place of the above terms if the other terms can achieve the same purpose.

[0048] As used in this application and the claims, unless otherwise clearly indicated through the context, terms such as "a," "one," "one kind," and / or "the" do not specifically refer to the singular but may include the plural. In general, the terms "comprise" and "containing" are merely intended to indicate the inclusion of explicitly identified steps and elements, and these steps and elements are not intended to be an exclusive listing, and a method or apparatus may include other steps or elements.

[0049] In this application, flowcharts are used to describe the operations performed by the system according to the embodiment of the application. It should be understood that the preceding and subsequent operations are not necessarily performed in exact order. Instead, the steps may be processed in reverse order or simultaneously. Also, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0050] The vibration device according to the embodiment of the present specification may be applied to an acoustic output device. The acoustic output device may include, but is not limited to, a bone conduction speaker, an air conduction speaker, a bone conduction hearing aid, an air conduction hearing aid, and the like. The vibration device according to the embodiment of the present specification may include a piezoelectric element. Since the piezoelectric element can convert an input voltage into a displacement and output it by the action of the inverse piezoelectric effect, a vibration device that outputs a displacement by a piezoelectric element is also called a piezoelectric vibration device. The operation mode of the piezoelectric element in the piezoelectric vibration device generally uses a d33 operation mode and a d31 operation mode. In the d33 operation mode, the polarization direction of the piezoelectric element is the same as the displacement output direction. In the d31 operation mode, the polarization direction of the piezoelectric element is perpendicular to the displacement output direction. Piezoelectric elements generally have a high resonant frequency, so piezoelectric vibration devices can generally provide high-frequency output; however, piezoelectric elements have poor low-frequency response, generally have many vibration modes within the audible range (e.g., 20 Hz to 20 KHz), and are difficult to form a flat frequency response curve, which affects the sound quality of the output audio when the vibration device is applied to an audio output device.

[0051] In order to solve the problem that the low-frequency response of the piezoelectric vibration device is poor and there are many modes in the frequency range of the audible band, the vibration device according to the embodiment of the present specification further includes a mass element and an elastic element, and uses the combination structure of the elastic element and the mass element to build a first resonance peak in the low frequency range (e.g., 20Hz to 2000Hz), and uses the piezoelectric element to build a second resonance peak in the high frequency range (e.g., 1000Hz to 20000Hz), so that a flat curve can be formed between the first resonance peak and the second resonance peak. In some embodiments, the piezoelectric element can use a d33 operation mode, and the piezoelectric element in the d33 operation mode has a high resonance frequency and can reduce the operation mode of the piezoelectric element in the frequency range of the audible band, and the piezoelectric element in the d33 operation mode with different boundary conditions (e.g., with a fixed connection boundary or without a fixed connection boundary) can also be used to compensate for the loss of high-frequency response of the vibration device.

[0052] FIG. 1 is an exemplary module diagram of a vibration device according to some embodiments of the present disclosure. In some embodiments, the vibration device 100 may include a piezoelectric element 110, a mass element 120, and an elastic element 130. In some embodiments, the mass element 120 may be connected to the piezoelectric element 110 by an elastic element. In some embodiments, the elastic element 130 may be one, and the mass element 120 may be connected to the piezoelectric element 110 by one elastic element 130. In some embodiments, the elastic element 130 may be multiple, and the mass element 120 may be connected to the piezoelectric element 110 by one or more elastic elements 130. In some embodiments, the piezoelectric element 110 may be one or multiple. In some embodiments, the mass element 120 may be connected to one piezoelectric element 110. In some embodiments, the mass element 120 may be connected to multiple piezoelectric elements 110, respectively. In some embodiments, the multiple piezoelectric elements 110 may be connected to each other. In some embodiments, the multiple piezoelectric elements 110 may be directly connected. In some embodiments, multiple piezoelectric elements 110 may be connected by one or more elastic elements 130 .

[0053] The piezoelectric element 110 may be a component having a piezoelectric effect. In some embodiments, the piezoelectric element 110 may be made of a material having a piezoelectric effect, such as a piezoelectric ceramic, a piezoelectric polymer, or the like. In some embodiments, the piezoelectric element 110 may be configured to generate vibrations based on an electrical signal. For example, when an alternating electrical signal is applied to the piezoelectric element 110, the piezoelectric element 110 may reciprocate to generate vibrations. In some embodiments, the piezoelectric element 110 may have a vibration direction that is the same as the polarization direction. In some embodiments, the piezoelectric element 110 may have a vibration direction that is mutually perpendicular to the polarization direction.

[0054] In some embodiments, the number of the piezoelectric elements 110 may be one or more. In some embodiments, when the number of the piezoelectric elements 110 is more than one, the plurality of piezoelectric elements 110 may be connected by the elastic element 130. In some embodiments, any one of the piezoelectric elements 110 connected to each other by the elastic element 130 may be further connected to the mass element 120 by another elastic element 130. In some embodiments, the plurality of piezoelectric elements 110 may be connected together in series along the vibration direction of the plurality of piezoelectric elements 110, and the series-connected piezoelectric elements 110 may be connected to the mass element 120 by the elastic element 130.

[0055] In some embodiments, the piezoelectric element 110 may be a single ring structure, and the single ring structure refers to a structure in which the shape of the projection of the piezoelectric element 110 along the axial direction is a single ring shape. For example, when the number of the piezoelectric element 110 is one, the piezoelectric element 110 is a single ring structure. In some embodiments, the piezoelectric element 110 may be a multiple ring structure (e.g., a double ring structure, a triple ring structure, etc.), and the multiple ring structure refers to a structure in which the shape of the projection of the piezoelectric element 110 along the axial direction is a multiple ring shape. For example, when the number of the piezoelectric elements 110 is two, the ring structures of the two piezoelectric elements 110 may have different ring outer diameters, and the two piezoelectric elements 110 may be connected by one or more elastic elements 130, and in this case, the two piezoelectric elements 110 and the elastic element 130 connecting these two piezoelectric elements 110 form a double ring structure. A piezoelectric element having a ring structure (e.g., a single ring structure or a double ring structure) has a high resonant frequency and can reduce the number of modes within the audible range of the piezoelectric element; after constructing a low-frequency peak through structural design (e.g., connecting an elastic element and a mass element), a flat curve can be formed between the low-frequency peak and the resonant peak of the piezoelectric element; when the vibration device 100 is applied to an audio output device, the sound quality of the output audio of the vibration device 100 or the audio output device can be improved.

[0056] In some embodiments, the piezoelectric element 110 may be a single-layer ring structure. In some embodiments, the piezoelectric element 110 may further be a double-layer ring structure. For example, the one or more piezoelectric elements 110 may include at least two piezoelectric elements, which are connected to each other along an axial direction to form a double-layer ring structure. The mass element 120 is connected to the at least two piezoelectric elements by one or more elastic elements 130, respectively. In some embodiments, the piezoelectric element 110 may be a multi-layer ring structure, which is connected to each other along an axial direction by more piezoelectric elements.

[0057] In some embodiments, the piezoelectric element 110 may have a polarization direction that is the same as the displacement output direction. In some embodiments, by making the displacement output end of the piezoelectric element 110 a vibration end, the polarization direction of the piezoelectric element 110 becomes the same as the vibration direction of the piezoelectric element 110, and as will be understood, the piezoelectric element 110 can generate vibration along the polarization direction of the piezoelectric element 110 under the action of an electric signal. In some embodiments, one or more piezoelectric elements 110 may include a ring-shaped structure, and the ring-shaped structure may be a columnar structure having a ring-shaped end surface. In some embodiments, the polarization direction of the piezoelectric element 110 may be parallel to the axial direction of the ring-shaped structure, and under the action of an electric signal, the piezoelectric element 110 can generate vibration along the axial direction of the ring-shaped structure of the piezoelectric element 110. The axis of the ring-shaped structure may be a virtual line connecting the geometric center of the two ring-shaped end surfaces of the columnar structure and the geometric center of any cross section parallel to the ring-shaped end surfaces. For example, when the ring structure is a circular cylindrical structure, the axis is a straight line connecting the centers of the two circular end faces. Also, for example, when the ring structure is a trapezoidal circular cylindrical structure, the axis is a straight line connecting the geometric centers of the two trapezoidal end faces. In some embodiments, the axis direction of the ring structure is perpendicular to the ring surface of the ring structure. In some embodiments, the shape of the ring end face of the ring structure may include, but is not limited to, a circular ring, an elliptical ring, a curved ring, a polygonal ring, etc. In some embodiments, the polarization direction of the piezoelectric element 110 is parallel to the axial direction of the ring structure, and under the action of an electric signal, the piezoelectric element 110 can generate vibration along the axial direction of the ring structure of the piezoelectric element 110.

[0058] The mass element 120 may be an element having a certain mass. In some embodiments, the mass element 120 may be a diaphragm or membrane of the vibration device 100, so that the vibration device 100 can output vibrations through the mass element 120. In some embodiments, the material of the mass element 120 may be a metallic material or a non-metallic material. The metallic material may include, but is not limited to, steel (e.g., stainless steel, carbon steel, etc.), lightweight alloys (e.g., aluminum alloy, beryllium copper, magnesium alloy, titanium alloy, etc.), etc., or any combination thereof. The non-metallic material may include, but is not limited to, polymeric materials, glass fibers, carbon fibers, graphite fibers, silicon carbide fibers, etc. In some embodiments, the projection of the mass element 120 along the vibration direction may be a regular and / or irregular polygon, such as a circle, annulus, rectangle, pentagon, hexagon, etc.

[0059] In some embodiments, the mass element 120 may be connected to the piezoelectric element 110 by an elastic element 130, and vibrations output from the piezoelectric element 110 may be transferred to the mass element 120 by the elastic element 130. In some embodiments, the vibration device 100 may generate a first resonant peak by resonating the mass element 120 and the elastic element 130 connected thereto. The magnitude of a first resonant frequency corresponding to the first resonant peak is affected by the mass of the mass element 120 and the elastic coefficient of the elastic element 130. In some embodiments, the frequency of the first resonant peak (also referred to as the first resonant frequency) may be expressed by Equation (1):

[0060]

number

[0061] where f represents the first resonant frequency, m represents the mass of the mass element 120, and k represents the elastic modulus of the elastic element 120. As can be seen from equation (1), by adjusting the mass of the mass element 120 and / or the elastic modulus of the elastic element 120, the magnitude of the first resonant frequency corresponding to the first resonant peak can be adjusted to make the first resonant peak fall within a desired frequency range.

[0062] In some embodiments, the mass element 120 may be connected to the inside of the piezoelectric element 110 by the elastic element 130. In some embodiments, when the piezoelectric element 110 generates vibrations based on an electric signal, the vibrations are transmitted to the mass element 120 by the elastic element 130, and the mass element 120 generates vibrations parallel to the vibration direction of the piezoelectric element 110. In some embodiments, the projection of the mass element 120 along its vibration direction may be within the projection of the piezoelectric element 110 along its vibration direction. In some embodiments, the mass element 120 may be a solid columnar structure when located inside the piezoelectric element 110, for example, a solid cylindrical structure. In other embodiments, the mass element 120 may be another shape structure when located inside the piezoelectric element 110, for example, a ring-shaped structure with an outer diameter smaller than the inner diameter of the piezoelectric element 110.

[0063] In some embodiments, mass element 120 may be located outside of piezoelectric element 110. When mass element 120 is located outside of piezoelectric element 110, it may be annular in shape and the inner diameter of the annulus may be larger than the outer diameter of the annular structure of piezoelectric element 110, such that the projection of mass element 120 along the axis of piezoelectric element 110 may be other than the projection of piezoelectric element 110 along its axis.

[0064] In some embodiments, the mass element 120 may be located between the piezoelectric elements 110. In some embodiments, the piezoelectric element 110 may include a first piezoelectric element and a second piezoelectric element having different diameters, the second piezoelectric element being disposed inside the first piezoelectric element, and the mass element 120 being located between the first and second piezoelectric elements. In some embodiments, the shape of the mass element 120 may be annular, and the projection of the mass element 120 along the axis of the piezoelectric element 110 may be between the projections of the first and second piezoelectric elements along the axis of the piezoelectric element 110.

[0065] In some embodiments, when the shape of the mass element 120 is annular, a cover plate may be installed on the side of the mass element 120 that is distant from the piezoelectric element 110 along the axial direction of the piezoelectric element 110. The cover plate can seal the side of the mass element 120 that is distant from the piezoelectric element 110 along the axial direction of the piezoelectric element 110. For example, when the shape of the mass element 120 is annular, the cover plate may be a circular structure, and the periphery of the cover plate is connected to the side of the mass element 120 that is distant from the piezoelectric element 110 along the axial direction of the piezoelectric element 110. By installing the cover plate on the side of the mass element 120 that is distant from the piezoelectric element 110 along the axial direction of the piezoelectric element 110, the cover plate can be used as a vibration plate to transmit a vibration signal. In some embodiments, when the vibration device 100 is applied to an acoustic device, the cover plate connects the mass element 120 to another structure of the acoustic device, such as a vibration membrane, so that the vibration device 100 drives the vibration membrane to vibrate by the mass element 120.

[0066] The elastic element 130 may be an element that can be elastically deformed under the action of an external load. In some embodiments, the elastic element 130 may be a material having high elasticity (i.e., elastic deformation is easily generated) so that the mass element 120 connected thereto has good vibration response ability. In some embodiments, the material of the elastic element 130 may include, but is not limited to, one or more of metal materials, polymer materials, rubber-based materials, etc. In some embodiments, the number of the elastic elements 130 may be one or more. In some embodiments, the mass element 120 may be connected to the piezoelectric element 110 by one elastic element 130. For example, the shape of the elastic element 130 may be a ring, and the mass element 120 and the piezoelectric element 110 may be connected by the ring-shaped elastic element 130. In some embodiments, the mass element 120 may be connected to the piezoelectric element 110 by multiple elastic elements 130. For example, the elastic element 130 may include a rod-like structure, with multiple elastic elements 130 distributed along the circumference of the piezoelectric element 110 and connected to the mass element 120 .

[0067] In some embodiments, the elastic element 130 may be a vibration transmission sheet. When the elastic element 130 connects the mass element 120 and the piezoelectric element 110, the elastic element 130 transmits the vibration generated by the piezoelectric element 110 to the mass element 120, so that the mass element 120 can generate vibration. In some embodiments, the elastic element 130 may be a connecting rod installed on the vibration transmission sheet, so as to make the manufacturing process of the vibration device 100 simpler and faster.

[0068] In some embodiments, the elastic element 130 may be a single layer structure, which refers to one or more elastic elements 130 located in the same plane perpendicular to the axial direction of the piezoelectric element 110. In some embodiments, the elastic element 130 may be a multi-layer structure, which refers to multiple elastic elements located in different planes perpendicular to the axial direction of the piezoelectric element 110.

[0069] In some embodiments, the shape of the elastic element 130 may include at least one of a broken line, an S-shape, a spline curve, a circular arc, and a straight line, but is not limited thereto. The shape of the elastic element 130 may be set according to the demands of the vibration device 100 (for example, the position of the first resonance peak, the difficulty of processing the vibration device 100, etc.).

[0070] In some embodiments, the elastic element 130 may have multiple curved segments. In some embodiments, the curved directions of the multiple curved segments may be the same. In some embodiments, the curved directions of the multiple curved segments may be different. In some embodiments, the curved directions of the multiple curved segments may be opposite. For example, when the shape of the elastic element 130 is a folded line, the folded line may include a first curved segment and a second curved segment, and the curved direction of the first curved segment may be folded first in a first direction, and the curved direction of the second curved segment may be folded first in a second direction, and the second direction is set opposite to the first direction. For more explanations on the bending direction of the elastic element and its setting, please refer to the related description of FIG. 12 in this specification.

[0071] In some embodiments, during the vibration process of the vibration device 100, the elastic element 130 may have a curved shape and thus provide a shear stress to the mass element 120, and if the elastic elements 130 provide the shear stress to the mass element 120 in the same direction, the mass element 120 may have a tendency to rotate about its central axis. The shear stress may be a stress that the elastic element 130 provides to the mass element 120 (and / or the piezoelectric element 110) and is tangent to any cross section perpendicular to the vibration direction of the mass element 120, and the shear stress may cause the mass element 120 to have a tendency to rotate about its central axis. In some embodiments, curved segments of the elastic element 130 with different curvature directions may provide shear stresses with different curls to the mass element 120 connected to the elastic element 130. Curl may be a vector operator for evaluating the rotational characteristics of the vector field of shear stress, the magnitude of the vector operator may evaluate the degree of rotation of the vector field of shear stress, and the direction of the vector operator may evaluate the direction of rotation of the vector field of shear stress. The direction of curl may be determined using the right-hand rule based on the direction of rotation, for example, when the mass element 120 generates a rotation (or tendency to rotate) under the shear stress provided by the elastic element 130, based on the right-hand rule, the curvature direction of the four fingers coincides with the rotation (or tendency to rotate) direction of the ring structure, and the pointing of the thumb is the direction of curl. In some embodiments, the curved segment of the elastic element 130 with the opposite curvature direction can provide the mass element 120 connected to the elastic element 130 with the shear stress with the opposite curl. By providing curved segments with shear stresses that have opposite curls, the shear stresses that different portions of the elastic element 130 provide to the mass element 120 can cancel each other out, so that the entire elastic element 130 does not provide a shear stress to the mass element 120, avoiding any tendency for the mass element 120 to rotate.

[0072] In some embodiments, when the number of elastic elements 130 is multiple, the bending directions of adjacent elastic elements 130 are different. In some embodiments, when the number of elastic elements 130 is multiple, the bending directions of adjacent elastic elements 130 are opposite. In some embodiments, when the elastic element 130 has a single-layer structure, the bending directions of adjacent elastic elements 130 are opposite to each other, because the projections of the multiple elastic elements 130 along the axial direction of the piezoelectric element 110 have two symmetrical axes perpendicular to each other. For example, the elastic element 130 may have an X-shape, and the X-shaped elastic element has two symmetrical axes perpendicular to each other. By installing the elastic elements 130 with opposite bending directions, the curl direction of the shear stress provided to the mass element 120 by the multiple elastic elements 130 with opposite bending directions can be reversed, so that the shear stress provided to the mass element 120 by the multiple elastic elements 130 with opposite bending directions can be offset by each other, and the mass element 120 does not tend to rotate.

[0073] In some embodiments, when the elastic element 130 is a multi-layer structure, the elastic elements 130 of adjacent layers may have different curvature directions. In some embodiments, the elastic element 130 may be a two-layer structure and may include a first helical structure and a second helical structure connected to the mass element 120 and one or more piezoelectric elements 110, respectively, in different planes perpendicular to the axial direction of the piezoelectric element 110. In some embodiments, the first helical structure and the second helical structure may have the same axis and opposite helical directions. By locating the first helical structure and the second helical structure with opposite helical directions, the curl directions of the shear stress provided by the elastic elements 130 of different layers to the mass element 120 can be opposite, so that the shear stress provided by the elastic elements 130 of different layers to the mass element 120 can be offset each other, and further avoid the mass element 120 from having a tendency to rotate.

[0074] In some embodiments, the vibration device 100 can form at least two resonance peaks within a frequency range of the audible band. In some embodiments, at least one of the one or more elastic elements 130 and the mass element 120 can resonate to generate a first resonance peak, and the one or more piezoelectric elements 110 can resonate to generate a second resonance peak. In some embodiments, the frequency corresponding to the first resonance peak (which may also be referred to as a first resonance frequency) may be in a low frequency range (e.g., less than 2000 Hz), and the frequency corresponding to the second resonance peak (which may also be referred to as a second resonance frequency) may be in a mid-high frequency range (e.g., greater than 1000 Hz). In some embodiments, the second resonance frequency corresponding to the second resonance peak may be higher than the first resonance frequency corresponding to the first resonance peak. In some embodiments, no resonance valley appears between the second resonance peak and the first resonance peak, forming a flat curve, thereby improving the sound quality of the output sound of the vibration device 100.

[0075] In some embodiments, as can be seen from equation (1), the frequency range of the first resonant frequency corresponding to the first resonant peak can be adjusted by adjusting the mass of the mass element 120 and / or the elastic modulus of the elastic element 130. In some embodiments, the frequency range of the first resonant frequency corresponding to the first resonant peak may be 50Hz to 2000Hz. In some embodiments, the frequency range of the first resonant frequency corresponding to the first resonant peak may be 50Hz to 1500Hz. In some embodiments, the frequency range of the first resonant frequency corresponding to the first resonant peak may be 50Hz to 1000Hz. In some embodiments, the frequency range of the first resonant frequency corresponding to the first resonant peak may be 50Hz to 500Hz. In some embodiments, the frequency range of the first resonant frequency corresponding to the first resonant peak may be 50Hz to 200Hz.

[0076] In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak can be adjusted by adjusting the structural parameters (e.g., dimensions, shape, mass, material, etc.) of the piezoelectric element 110. In some embodiments, the second resonant frequency may be a natural frequency of the piezoelectric element 110. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 1000 Hz to 50000 Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 1000 Hz to 40000 Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 1000 Hz to 30000 Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 1000 Hz to 20000 Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 1000 Hz to 10000 Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 2000Hz to 10000Hz. In some embodiments, the frequency range of the second resonant frequency corresponding to the second resonant peak may be 3000Hz to 10000Hz.

[0077] In some embodiments, in order to ensure that the frequency response curve of the vibration device 100 has a wide flat section between the first and second resonance peaks and the low frequency response of the vibration device 100 and the sound quality of the output sound, the frequency ratio of the second resonance frequency corresponding to the second resonance peak to the first resonance frequency corresponding to the first resonance peak may be in the range of 20 to 200. In some embodiments, the frequency ratio of the second resonance frequency corresponding to the second resonance peak to the first resonance frequency corresponding to the first resonance peak may be in the range of 30 to 180. In some embodiments, the frequency ratio of the second resonance frequency corresponding to the second resonance peak to the first resonance frequency corresponding to the first resonance peak may be in the range of 40 to 160. In some embodiments, the frequency ratio of the second resonance frequency corresponding to the second resonance peak to the first resonance frequency corresponding to the first resonance peak may be in the range of 50 to 150.

[0078] In some embodiments, the vibration device 100 may further have a third resonant peak when vibrating, and a frequency corresponding to the third resonant peak (which may also be referred to as a third resonant frequency) may be between the first resonant frequency corresponding to the first resonant peak and the second resonant frequency corresponding to the second resonant peak. In some embodiments, the vibration device 100 may have a double ring structure, and the third resonant peak may be generated by resonance of the double ring structure. In some embodiments, when the piezoelectric element 110 is a double ring structure and the mass element 120 is located at the innermost position, the inner piezoelectric element (e.g., the second piezoelectric element) and the mass element 120 (and the elastic element 130 connecting the inner piezoelectric element and the mass element 120) may constitute a whole mass, which is larger than the mass of the mass element 120 (i.e., the vibration mass increases), so that the resonance frequency of the low frequency peak of the vibration device 100 is reduced, and the first resonance peak in the frequency response curve of the vibration device 100 is expressed as shifting to a lower frequency, and the vibration device 100 having the double ring structure can also generate a third resonance peak between the first resonance peak and the second resonance peak when vibrating. In some embodiments, the formation of the third resonance peak does not affect the position of the high frequency resonance peak (e.g., the second resonance peak), and also enhances the high frequency resonance valley, improving the high frequency response of the vibration device 100.

[0079] In some embodiments, in order to meet the demand for miniaturization of devices, the maximum dimension of the projection along the vibration direction of the vibration device 100 is 60 mm or less. The maximum dimension of the projection along the vibration direction of the vibration device 100 refers to the maximum value of the distance between any two points of the outer contour of the projection. For example, if the maximum contour of the projection along the vibration direction of the vibration device 100 is a circle, the maximum dimension of the projection along the vibration direction of the vibration device 100 is the diameter of the circle. For example, if the maximum contour of the projection along the vibration direction of the vibration device 100 is an ellipse, the maximum dimension of the projection along the vibration direction of the vibration device 100 is the major axis of the ellipse. For example, if the maximum contour of the projection along the vibration direction of the vibration device 100 is a square, the maximum dimension of the projection along the vibration direction of the vibration device 100 is the diagonal of the square. In some embodiments, if the mass element 120 is installed on the outermost side of the vibration device 100, the maximum dimension of the projection along the vibration direction of the vibration device 100 may be the maximum dimension of the projection along the vibration direction of the mass element 120. In some embodiments, when the piezoelectric element 110 is installed at the outermost position of the vibration device 100, the maximum dimension of the projection along the vibration direction of the vibration device 100 may be the maximum dimension of the projection along the vibration direction of the piezoelectric element 110.

[0080] In some embodiments, the vibration device 100 may include a piezoelectric beam that is directly or indirectly connected to the mass element 120. For example, the piezoelectric beam may be located on a side of the mass element 120 away from the piezoelectric element 110 and directly connected to the mass element 120. Also, for example, the piezoelectric beam may be indirectly connected to the mass element 120 by the elastic element 130. In some embodiments, the piezoelectric beam may be configured to generate vibration along the axis of the ring structure of the piezoelectric element 110 based on an electric signal. In some embodiments, the piezoelectric beam may include at least one first piezoelectric sheet and at least one second piezoelectric sheet, the at least one first piezoelectric sheet and the at least one second piezoelectric sheet being disposed on either side of the piezoelectric beam along the axis of the ring structure of the piezoelectric element 110. In some embodiments, the at least one first piezoelectric sheet and the at least one second piezoelectric sheet may be polarized in opposite directions along the axis of the ring structure. That is, the first and second piezoelectric sheets have opposite polarization directions in the axial direction of the ring structure of the piezoelectric element 110. In some embodiments, the first and second piezoelectric sheets may have a displacement output direction perpendicular to the polarization direction. In some embodiments, the first and second piezoelectric sheets have opposite polarization directions, so that when voltage signals of the same direction are simultaneously applied, displacements of opposite directions are generated, and the piezoelectric beam can generate vibrations. For example, the first piezoelectric sheet can contract along an axial direction perpendicular to the ring structure, and the second piezoelectric sheet can expand along an axial direction perpendicular to the ring structure, so that the piezoelectric beam can generate vibrations along the axial direction of the ring structure.

[0081] In some embodiments, the mass element 120 may include a first mass element and a second mass element, and the first mass element may be connected to a middle portion of the piezoelectric beam by at least one of the one or more elastic elements 130. In some embodiments, the first mass element may be connected to one or more piezoelectric elements 110 by the elastic element 130. In some embodiments, a second mass element may be connected to each end of the piezoelectric beam. In some embodiments, the first mass element may be connected to another location of the piezoelectric beam (e.g., a location proximate to an end of the piezoelectric beam) by at least one of the one or more elastic elements 130. In some embodiments, the vibration of the vibration device 100 may be output by a second mass element at the end of the piezoelectric beam. In some embodiments, the vibration of the vibration device 100 may also be output by the first mass element.

[0082] 2 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. As shown in FIG. 2, the vibration device 200 may include one or more piezoelectric elements 210, a mass element 220, and one or more elastic elements 230. At least one of the one or more elastic elements 230 may connect the mass element 220 and the piezoelectric element 210.

[0083] In some embodiments, the one or more piezoelectric elements 210 may include a first piezoelectric element 211, which may be a ring-shaped structure, with one end along the axial direction fixed (also referred to as a fixed end), and the mass element 220 is connected to a position other than this one end of the first piezoelectric element 211 by the elastic element 230. In the embodiments of the present specification, one end of a piezoelectric element (e.g., a first piezoelectric element, a second piezoelectric element, etc.) refers to the entire region having a certain thickness (e.g., 0.1%, 5%, or any thickness within a range of 0.1% to 30% of the total thickness of the ring structure) from one ring-shaped end face in the ring-shaped structure of the piezoelectric element along the axial direction of the ring structure. For example, the fixation of one end of the first piezoelectric element 211 along the axial direction may be fixation of one ring-shaped end face of the first piezoelectric element 211. For example, the fixation of one end of the first piezoelectric element 211 along the axial direction may be fixation of an inner surface and / or an outer surface of a ring-shaped structure of a certain thickness region near one ring-shaped end surface of the first piezoelectric element 211. In some embodiments, the elastic element 230 may be connected to another ring-shaped end surface opposite to the ring-shaped end surface of the fixed end. In some embodiments, the elastic element 230 may be connected to the inner surface of the ring-shaped structure, and the connection position on the inner surface does not belong to the region of the fixed end.

[0084] In some embodiments, the mass element 220 may be located inside the first piezoelectric element 211, and the axial projection of the mass element 220 is within the axial projection of the first piezoelectric element 211. The piezoelectric element 210, the elastic element 230 and the mass element 220 are arranged in order from the outside to the inside of the axial projection of the piezoelectric element 210. In some embodiments, the mass element 220, when located inside the first piezoelectric element 211, may be cylindrical (as shown in FIG. 2), ring-shaped, etc. in shape.

[0085] In some embodiments, the elastic element 230 connecting the mass element 220 and the first piezoelectric element 211 may be multiple, and the multiple elastic elements 230 may be distributed along the circumferential direction of the ring-shaped structure. In some embodiments, one end of the elastic element 230 may be connected to any one surface along the axial direction of the mass element 220 (e.g., the surface adjacent to the piezoelectric element 210). In other embodiments, one end of the elastic element 230 may be connected to the peripheral side surface of the mass element 220. In some embodiments, the other end of the elastic element 230 may be connected to any one surface of the non-fixed end of the piezoelectric element 210. For example, in some embodiments, the other end of the elastic element 230 may be connected to the annular end surface of the piezoelectric element 210 adjacent to the mass element 220. Also, for example, in some embodiments, the other end of the elastic element 230 may be connected to the inner peripheral side surface of the piezoelectric element 210. The connection positions of the elastic element 230 and the mass element 220 and / or the piezoelectric element 210 may be set according to the feasibility of the structure of the vibration device 200 .

[0086] In some embodiments, the mass element 220 and the elastic element 230 may resonate to generate a first resonant peak, and the first piezoelectric element 211 may resonate to generate a second resonant peak. A location of the first resonant peak, i.e., a magnitude of a first resonant frequency corresponding to the first resonant peak, may be determined by the mass of the mass element 220 and the elastic coefficient of the elastic element 230. A location of the second resonant peak, i.e., a magnitude of a second resonant frequency corresponding to the second resonant peak, may be determined by structural parameters (e.g., dimensions) of the piezoelectric element 210.

[0087] FIG. 3 is a frequency response curve diagram of a vibration device 200 according to some embodiments of the present specification. As shown in FIG. 3, the horizontal axis represents the resonant frequency of the vibration device 200 in Hz, and the vertical axis represents the acceleration output strength of the vibration device 200 in dB. In some embodiments, as shown in FIG. 3, the vibration device 200 can form at least two resonant peaks within a frequency range of an audible band (e.g., 20 Hz to 20 KHz), and the first resonant peak 310 may be generated by the resonance of the mass element 220 and the elastic element 230, and the second resonant peak 320 may be generated by the resonance of the piezoelectric element 210. In some embodiments, the frequency f1 of the first resonant peak 310 of the vibration device 200 may range from 50 Hz to 2000 Hz. In some embodiments, the frequency f1 of the first resonant peak 310 of the vibration device 200 may range from 50 Hz to 500 Hz. In some embodiments, the frequency f1 of the first resonant peak 310 of the vibration device 200 may range from 50 Hz to 300 Hz. In some embodiments, the frequency f1 of the first resonant peak 310 of the vibration device 200 may range from 50 Hz to 200 Hz. In some embodiments, the frequency f1 of the first resonant peak 310 of the vibration device 200 may range from 100 Hz to 200 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 1000 Hz to 20000 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 2000 Hz to 10000 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 2000 Hz to 8000 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 2000 Hz to 7000 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 3000 Hz to 7000 Hz. In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may range from 4000 Hz to 7000 Hz.In some embodiments, the frequency f2 of the second resonant peak 320 of the vibration device 200 may be in the range of 5000 Hz to 7000 Hz. The frequency response curve between the first resonant peak 310 and the second resonant peak 320 may be flat, and within the frequency range between the first resonant frequency f1 and the second resonant frequency f2, the vibration device 200 has a high output response capability, and when the vibration device 200 is applied to an audio output device, it can output sound with high sound quality.

[0088] 4A is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. In some embodiments, as shown in FIG. 4A, the mass element 420 may be located outside the first piezoelectric element 411, and the projection of the mass element 420 along the axial direction of the first piezoelectric element 411 is other than the projection of the mass element 420 along the axial direction of the first piezoelectric element 411, and the mass element 420 and the first piezoelectric element 411 are connected by the elastic element 430. The first piezoelectric element 411, the elastic element 430, and the mass element 420 are arranged in order from the inside to the outside of the projection of the first piezoelectric element 411 along the axial direction. In some embodiments, when the mass element 420 is located outside the first piezoelectric element 411, the shape of the mass element 420 may be a ring shape.

[0089] In some embodiments, when the mass element 420 is located outside the first piezoelectric element 411, a cover plate may be installed on the side of the mass element 420 away from the first piezoelectric element 411 along the axial direction of the first piezoelectric element 411. The cover plate can seal the side of the mass element 420 away from the first piezoelectric element 411 along the axial direction of the first piezoelectric element 411. For example, the cover plate may be a circular structure, and the periphery of the cover plate is aligned with and tightly connected to the side of the mass element 420 away from the first piezoelectric element 411 along the axial direction of the first piezoelectric element 411. By installing the cover plate on the side of the mass element 420 away from the first piezoelectric element 411 along the axial direction of the first piezoelectric element 411, the cover plate can be used as a vibration plate to transmit a vibration signal. The cover plate can also connect the mass element 420 to another structure of the vibration device 400, such as a vibration membrane.

[0090] FIG. 4B is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. When the mass element 420 is located outside the first piezoelectric element 411, the frequency response curve diagram of the vibration device 400 is as shown in FIG. 4B. In some embodiments, the frequency f1 (also referred to as the first resonance frequency) of the first resonance peak 401 of the vibration device 400 may range from 50 Hz to 4000 Hz. In some embodiments, the frequency f1 of the first resonance peak 401 of the vibration device 400 may range from 50 Hz to 500 Hz. In some embodiments, the frequency f1 of the first resonance peak 401 of the vibration device 400 may range from 50 Hz to 300 Hz. In some embodiments, the frequency f1 of the first resonance peak 401 of the vibration device 400 may range from 50 Hz to 200 Hz. In some embodiments, the frequency f1 of the first resonance peak 401 of the vibration device 400 may range from 100 Hz to 200 Hz. In some embodiments, the frequency f2 (also referred to as the second resonant frequency) of the second resonant peak 402 of the vibration device 400 may range from 1000 Hz to 40000 Hz. In some embodiments, the frequency f2 of the second resonant peak 402 of the vibration device 400 may range from 4000 Hz to 10000 Hz. In some embodiments, the frequency f2 of the second resonant peak 402 of the vibration device 400 may range from 4000 Hz to 8000 Hz. In some embodiments, the frequency f2 of the second resonant peak 402 of the vibration device 400 may range from 4000 Hz to 7000 Hz. In some embodiments, the frequency f2 of the second resonant peak 402 of the vibration device 400 may range from 4000 Hz to 6000 Hz.

[0091] In some embodiments, the one or more piezoelectric elements may not only include a first piezoelectric element but also a second piezoelectric element, and the second piezoelectric element may be disposed inside the first piezoelectric element. In some embodiments, the first piezoelectric element may include a first ring-shaped structure, and the second piezoelectric element may include a second ring-shaped structure, and the second piezoelectric element is disposed inside the first ring-shaped structure.

[0092] 5 is an example structural diagram of a vibration device according to some embodiments of the present disclosure. As shown in FIG. 5, the vibration device 500 may include one or more piezoelectric elements 510, a mass element 520, and one or more elastic elements 530. At least one of the one or more elastic elements 530 may connect the mass element 520 and the piezoelectric element 510.

[0093] In some embodiments, the one or more piezoelectric elements 510 may include a first piezoelectric element 511 including a first ring-shaped structure and a second piezoelectric element 512 including a second ring-shaped structure, and the second piezoelectric element 512 is disposed inside the first ring-shaped structure. In some embodiments, one axial end of the first piezoelectric element 511 (e.g., an end away from the mass element 520) may be fixed, and the second piezoelectric element 512 is connected to another position of the first piezoelectric element 511 other than the fixed end by at least one of the one or more elastic elements 530, an axial projection of the mass element 520 is within an axial projection of the second piezoelectric element 512, and the mass element 520 is connected to the second piezoelectric element 512 by at least another one of the one or more elastic elements 530. In some embodiments, the elastic element 530 may include a first elastic element 531 and a second elastic element 532. The first elastic element 531 is located between the first piezoelectric element 511 and the second piezoelectric element 512, and the first piezoelectric element 511 and the second piezoelectric element 512 are connected by the first elastic element 531. The second elastic element 532 is located between the second piezoelectric element 512 and the mass element 520, and the second piezoelectric element 512 and the mass element 520 are connected by the second elastic element 532.

[0094] In some embodiments, by installing the second piezoelectric element 512 in the vibration device 500, the second piezoelectric element 512 and the mass element 520 (as well as the elastic element connecting the second piezoelectric element 512 and the mass element 520) may constitute an entire mass, and when the entire mass resonates with the elastic element connecting the entire mass and the first piezoelectric element 511, the entire mass is larger than the mass of the mass element, so that the first resonance peak of the vibration device 500 shifts to a lower frequency, and when the vibration device 500 vibrates, a third resonance peak between the first resonance peak and the second resonance peak may also be generated due to the resonance of the double ring structure, which can be expressed as additionally forming another resonance peak, i.e., the third resonance peak, at a position between the first resonance peak and the second resonance peak in the frequency response curve of the vibration device 500. In some embodiments, the third resonance frequency corresponding to the third resonance peak may be between the first resonance frequency corresponding to the first resonance peak and the second resonance frequency corresponding to the second resonance peak.

[0095] In some embodiments, the frequency range of the first resonance peak of the vibration device 500 having a double ring structure may be 50Hz to 2000Hz. In some embodiments, the frequency range of the first resonance peak of the vibration device 500 having a double ring structure may be 50Hz to 1000Hz. In some embodiments, the frequency range of the first resonance peak of the vibration device 500 having a double ring structure may be 50Hz to 500Hz. In some embodiments, the frequency range of the first resonance peak of the vibration device 700 having a double ring structure may be 50Hz to 300Hz. In some embodiments, the frequency range of the first resonance peak of the vibration device 500 having a double ring structure may be 50Hz to 200Hz. In some embodiments, the frequency range of the first resonance peak of the vibration device 500 having a double ring structure may be 50Hz to 100Hz.

[0096] FIG. 6 is a frequency response curve diagram of a vibration device 500 according to some embodiments of the present disclosure. Curve 610 may represent a frequency response curve of a vibration device in which only a first piezoelectric element is installed, and curve 620 may represent a frequency response curve of a vibration device in which a first piezoelectric element and a second piezoelectric element are installed, and the phase difference between the electrical signals received by the first piezoelectric element and the second piezoelectric element is 0°. As can be seen by comparing curves 610 and 620, when a second piezoelectric element is additionally installed in the vibration device, not only a first resonance peak 601 and a second resonance peak 602 can be formed in the frequency response curve 620 of the vibration device, but also another resonance peak, i.e., a third resonance peak 603, can be additionally formed. In some embodiments, when a second piezoelectric element is additionally installed in the vibration device, a third resonance peak 603 can be formed in the frequency response curve 620 of the vibration device, and a resonance valley 604 can be formed between the first resonance peak 601 and the third resonance peak 603. The resonant valley 604 is formed by canceling out the vibration output of the first and second piezoelectric elements because the vibration output directions at the frequency position of the resonant valley 604 are opposite to each other. In some embodiments, the location of the resonant valley 604 is related to the geometry of the first and second piezoelectric elements and the geometry of the elastic element. In some embodiments, the resonant valley 604 may be filled by adjusting the phase of the electrical signal between the first and second piezoelectric elements. In some embodiments, the low frequency sensitivity of the vibration device may increase with an increase in the phase difference of the electrical signal between the first and second piezoelectric elements. The phase difference of the electrical signal between the first and second piezoelectric elements has little effect on the high frequency characteristics of the vibration device.

[0097] 6, curve 630 represents a frequency response curve of the vibration device when the phase difference between the electric signals received by the first and second piezoelectric elements is 45°, curve 640 represents a frequency response curve of the vibration device when the phase difference between the electric signals received by the first and second piezoelectric elements is 90°, and curve 650 represents a frequency response curve of the vibration device when the phase difference between the electric signals received by the first and second piezoelectric elements is 135°. As can be seen by comparing curves 630, 640, and 650, when other parameters are the same, the larger the phase difference between the electric signals received by the first and second piezoelectric elements, the shallower the resonance valley formed between the first and third resonance peaks, and the better the low-frequency response of the vibration device.

[0098] In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 45° and 180° to ensure the low frequency response of the vibration device. In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 60° and 180° to ensure the low frequency response of the vibration device. In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 80° and 180° to ensure the low frequency response of the vibration device. In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 100° and 180° to ensure the low frequency response of the vibration device. In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 45° and 120° to ensure the low frequency response of the vibration device. In some embodiments, the phase difference between the electric signals received by the first and second piezoelectric elements may be between 45° and 90° to ensure the low frequency response of the vibration device.

[0099] In some embodiments, when the vibration device includes a first piezoelectric element and a second piezoelectric element, the mass element may be located outside the first piezoelectric element. Figure 7 is an exemplary structural diagram of a vibration device according to some embodiments herein. As shown in Figure 7, the one or more piezoelectric elements 710 may include a first piezoelectric element 711 including a first ring-shaped structure and a second piezoelectric element 712 including a second ring-shaped structure, and the second piezoelectric element 712 is disposed inside the first ring-shaped structure. In some embodiments, one axial end of the ring-shaped structure of the second piezoelectric element 712 may be fixed, and the first piezoelectric element 711 is connected to another position other than the fixed end of the second piezoelectric element 712 by at least one of the one or more elastic elements 730 (e.g., the second elastic element 732), the shape of the mass element 720 may be ring-shaped, the axial projection of the mass element 720 is other than the axial projection of the first piezoelectric element 711, and the mass element 720 is connected to the first piezoelectric element 711 by at least another one of the one or more elastic elements 730 (e.g., the first elastic element 731).

[0100] In some embodiments, when the vibration device 700 includes a first piezoelectric element 711 and a second piezoelectric element 712, and the mass element 720 is located outside the first piezoelectric element 711, a cover plate may be provided on the side of the mass element 720 away from the first piezoelectric element 711 along the axial direction of the first piezoelectric element 711.

[0101] In some embodiments, the first piezoelectric element 711 and the mass element 720 (and the elastic element connecting the first piezoelectric element 711 and the mass element 720) may constitute an entire mass, and when the entire mass resonates with the elastic element connecting the entire mass and the second piezoelectric element 712, the first resonance peak of the vibration device 700 may shift to a lower frequency, and a third resonance peak between the first resonance peak and the second resonance peak may also be generated due to the resonance of the double ring structure of the vibration device 700. In some embodiments, the frequency range of the first resonance peak of the vibration device 700 with the double ring structure may be similar to the frequency range of the first resonance peak of the vibration device 500, and the description will be omitted here.

[0102] FIG. 8 is a frequency response curve diagram of a vibration device 700 according to some embodiments of the present disclosure. Curve 810 may represent a frequency response curve of a vibration device in which only a first piezoelectric element is installed, and curve 820 may represent a frequency response curve of a vibration device in which a first piezoelectric element and a second piezoelectric element are installed, and the phase difference between the electrical signals received by the first piezoelectric element and the second piezoelectric element is 0°. As can be seen by comparing curves 810 and 820, when a second piezoelectric element is additionally installed in the vibration device, not only a first resonance peak 801 and a second resonance peak 802 but also a third resonance peak 803 can be additionally formed in the frequency response curve 820 of the vibration device. In some embodiments, when a second piezoelectric element is additionally installed in the vibration device, a third resonance peak 803 can be formed in the frequency response curve 820 of the vibration device, and a resonance valley 804 can be formed between the first resonance peak 801 and the third resonance peak 803. The resonant valley 804 is formed by canceling out the vibration output of the first and second piezoelectric elements because the vibration output directions at the frequency position corresponding to the resonant valley 804 are opposite to each other. In some embodiments, the location of the resonant valley 804 is related to the geometry of the first and second piezoelectric elements and the geometry of the elastic element. In some embodiments, the resonant valley 804 may be filled by adjusting the phase of the electrical signal between the first and second piezoelectric elements. In some embodiments, the low frequency sensitivity of the vibration device may increase with an increase in the phase difference of the electrical signal between the first and second piezoelectric elements. The phase difference of the electrical signal between the first and second piezoelectric elements has little effect on the high frequency characteristics of the vibration device.

[0103] In some embodiments, there may be a phase difference between the electrical signals received by the first and second piezoelectric elements, which affects the amplitude value of the resonant valley 804. As shown in FIG. 8, curve 830 represents a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 45°, curve 840 represents a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 90°, and curve 850 represents a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 135°. As can be seen by comparing curves 830, 840, and 850, when other parameters are the same, the greater the phase difference between the electrical signals received by the first and second piezoelectric elements, the shallower the resonant valley formed between the first and third resonant peaks, and the better the low-frequency response of the vibration device. In some embodiments, for a specific setting range of the phase difference between the electrical signals received by the first piezoelectric element and the second piezoelectric element, reference may be made to descriptions elsewhere in this specification.

[0104] In some embodiments, when the vibration device includes a first piezoelectric element and a second piezoelectric element, the mass element may be located between the first piezoelectric element and the second piezoelectric element. FIG. 9 is an exemplary structural diagram of a vibration device according to some embodiments herein. As shown in FIG. 9, in some embodiments, the shape of the mass element 920 may be annular, and the mass element 920 is located between a first annular structure of the first piezoelectric element 911 and a second annular structure of the second piezoelectric element 912. The axial projection of the mass element 920 is between the axial projections of the first piezoelectric element 911 and the second piezoelectric element 912. The mass element 920 is connected to the first piezoelectric element 911 by at least one of the one or more elastic elements 930 (e.g., the first elastic element 931) and connected to the second piezoelectric element 912 by at least another of the one or more elastic elements (e.g., the second elastic element 932). In some embodiments, the shape of the elastic elements 930 (e.g., the first elastic element 931 and / or the second elastic element 932) may be S-shaped, and adjacent S-shaped elastic elements 930 may be curved in opposite directions, so that adjacent S-shaped elastic elements 930 can provide shear stresses with opposite curls to the mass element 920, avoiding the mass element 920 from tending to rotate about its axis, and further preventing the vibration device 900 from generating rotational modes. In some embodiments, as shown in FIG. 9, adjacent S-shaped elastic elements 930 may have the same connection positions at the mass element 920 or the piezoelectric element 910 (e.g., the first piezoelectric element 911 and / or the second piezoelectric element 912). In other embodiments, adjacent S-shaped elastic elements 930 may have different connection positions at the mass element 920 or the piezoelectric element 910 (e.g., the first piezoelectric element 911 and / or the second piezoelectric element 912).

[0105] In some embodiments, the first piezoelectric element 911 or the second piezoelectric element 912 may have a fixed end along the axial direction. In some embodiments, when one axial end of the first piezoelectric element 911 is fixed, the two axial end faces of the second piezoelectric element 912 are freely placed, and the second piezoelectric element 912 may be a piezoelectric free ring, and the first piezoelectric element 911 may be a piezoelectric fixed ring. Alternatively, when one axial end of the second piezoelectric element 912 is fixed, the two axial end faces of the first piezoelectric element 911 are freely placed, and the first piezoelectric element 911 may be a piezoelectric free ring, and the second piezoelectric element 912 may be a piezoelectric fixed ring. In some embodiments, when different piezoelectric elements of the at least one piezoelectric element 910 have fixed ends along the axial direction, the vibration device 900 may have different frequency response curves. The entire mass composed of the piezoelectric free ring and the mass element 920 (and the elastic element connecting the piezoelectric free ring and the mass element 920) can resonate with the elastic element connecting the entire mass and the piezoelectric fixed ring, and the first resonance peak can be shifted to a lower frequency, and the piezoelectric free ring and the piezoelectric fixed ring are indirectly connected (i.e., connected by the first elastic element 931, the mass element 920, and the second elastic element 932), so that when the vibration device 900 vibrates, the piezoelectric free ring and the piezoelectric fixed ring can resonate to form a third resonance peak in the frequency response curve. The third resonance frequency corresponding to the third resonance peak may be between the first resonance frequency corresponding to the first resonance peak and the second resonance frequency corresponding to the second resonance peak. In some embodiments, the frequency range of the first resonance peak of the vibration device 900 can be similar to the frequency range of the first resonance peak of the vibration device 500, and the description will be omitted here.

[0106] FIG. 10 is a frequency response curve diagram of a vibration device according to some embodiments of the present specification. The frequency response curves other than the curve 1010 in FIG. 10 may be frequency response curves of a vibration device (e.g., the vibration device 900) in which a first piezoelectric element (e.g., the first piezoelectric element 911) has a fixed end along the axial direction. As shown in FIG. 10, the curve 1010 may represent a frequency response curve of a vibration device (e.g., the vibration device 200) in which only the first piezoelectric element is installed, and the curve 1020 may represent a frequency response curve of a vibration device in which the first piezoelectric element and the second piezoelectric element are installed and the phase difference between the electric signals received by the first piezoelectric element and the second piezoelectric element is 0°. As can be seen by comparing the curves 1010 and 1020, when the first piezoelectric element and the second piezoelectric element are installed in the vibration device, a third resonance peak 1003 other than the first resonance peak 1001 and the second resonance peak 1002 can also be formed in the frequency response curve 1020 of the vibration device. In some embodiments, the third resonant peak 1003 is caused by the first and second piezoelectric elements resonating. In some embodiments, a resonant valley 1004 formed in the frequency response curve 1020 of the vibration device may be before the first resonant peak 1001 when the mass element is located between the first and second piezoelectric elements compared to when the mass element is located outside the first piezoelectric element (or the mass element is located inside the second piezoelectric element). In some embodiments, the resonant valley 1004 may be filled by adjusting the phase of the electrical signal between the first and second piezoelectric elements.

[0107] 10, curve 1030 may represent a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 90°, and curve 1040 may represent a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 180°. As can be seen by comparing curves 1030 and 1040, when other parameters are the same, the larger the phase difference between the electrical signals received by the first and second piezoelectric elements, the shallower the resonance valley formed before the first resonance peak, and the better the low-frequency response of the vibration device. In some embodiments, the specific setting range of the phase difference between the electrical signals received by the first and second piezoelectric elements may be referred to in the description elsewhere in this specification.

[0108] FIG. 11 is a frequency response curve diagram of a vibration device according to some embodiments of the present specification. The frequency response curves other than the curve 1110 in FIG. 11 may be frequency response curves of a vibration device in which the second piezoelectric element (e.g., the second piezoelectric element 912) has a fixed end along the axial direction. The curve 1110 may represent a frequency response curve of a vibration device (e.g., the vibration device 200) in which only the first piezoelectric element is installed, and the curve 1120 may represent a frequency response curve of a vibration device (e.g., the vibration device 900) in which the first and second piezoelectric elements are installed and the phase difference between the electric signals received by the first and second piezoelectric elements is 0°. As can be seen by comparing the curves 1110 and 1120, when the first and second piezoelectric elements are installed in the vibration device, a third resonance peak 1103 other than the first resonance peak 1101 and the second resonance peak 1102 can also be formed in the frequency response curve 1120 of the vibration device. In some embodiments, the third resonant peak 1103 may be caused by the first and second piezoelectric elements resonating. In some embodiments, a resonant valley 1104 formed in the frequency response curve 1120 of the vibration device may be before the first resonant peak 1101 when the mass element is located between the first and second piezoelectric elements compared to when the mass element is located outside the first piezoelectric element (or when the mass element is located inside the second piezoelectric element). The resonant valley 1104 may be filled by adjusting the phase of the electrical signal between the first and second piezoelectric elements.

[0109] 11, curve 1130 may represent a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 90°, and curve 1140 may represent a frequency response curve of the vibration device when the phase difference between the electrical signals received by the first and second piezoelectric elements is 180°. As can be seen by comparing curves 1130 and 1140, when other parameters are the same, the larger the phase difference between the electrical signals received by the first and second piezoelectric elements, the shallower the resonance valley formed before the first resonance peak, and the better the low-frequency response of the vibration device. In some embodiments, the specific setting range of the phase difference between the electrical signals received by the first and second piezoelectric elements may be referred to in the description elsewhere in this specification.

[0110] In some embodiments, in the piezoelectric vibration device (e.g., vibration device 200, vibration device 400, vibration device 500, vibration device 700, and vibration device 900), the elastic element may provide elasticity so that the mass element can vibrate. Therefore, the structural design of the elastic element can affect the vibration characteristics of the vibration device. In some embodiments, in order to meet the demand for the elastic coefficient of the elastic element, the elastic element can be designed in a curved shape to increase the length of the elastic element and decrease the elastic coefficient of the elastic element. In this setting manner, if there is a rotational structure or an asymmetrical structure in the shape of the elastic element, it may generate a rotational mode when the mass element of the vibration device vibrates, thereby affecting the output of the vibration device (which may be expressed as a resonant valley in the frequency response curve), and further affecting the vibration performance of the vibration device. Therefore, the structure of the elastic element can be reasonably designed to ensure the vibration performance of the vibration device.

[0111] In some embodiments, the number of elastic elements connecting the mass element and the piezoelectric element may be multiple, and the multiple elastic elements may be distributed along the circumferential direction of the ring-shaped structure of the piezoelectric element. In some embodiments, the multiple elastic elements may be distributed symmetrically in the circumferential direction of the piezoelectric element, so that when the vibration device is likely to generate a rotational mode, the vibration device can utilize the symmetry of the elastic elements (e.g., the rotation directions of the elastic elements are opposite) to cancel the rotational mode in antiphase, thereby reducing or canceling the resonance valley generated by the rotational mode.

[0112] In some embodiments, the shape of the elastic element may include at least one of a broken line, an S-shape, a spline curve, a circular arc, and a straight line. In some embodiments, when the elastic element has a different shape, the elastic element may have different curved segments and curved directions. In some embodiments, a line connecting both ends of the elastic element is a reference line, and the elastic element may be connected alternately to both sides of the reference line to form subsegments, and a segment in which multiple subsegments are configured with the same alternating rule is a curved segment of the elastic element. In some embodiments, the curved direction may be a direction that expresses the alternating rule of multiple subsegments on both sides of the reference line. For example, if the shape of the elastic element is a broken line, the broken line first bends toward the first side of the reference line, then bends toward the second side of the reference line, and then bends toward the first side, and thus goes back and forth in a circular motion, the direction in which the bending start side of the broken line is located may be described as the curved direction of the broken line, and when the circular rule is broken, the curved segment of the broken line segment ends.

[0113] FIG. 12 is an exemplary structural diagram of an elastic element according to some embodiments of the present disclosure. In some embodiments, each of one or more elastic elements 1200 may have a plurality of curved segments, and adjacent curved segments among the plurality of curved segments may have opposite curved directions. For example, each of the plurality of elastic elements 1200 in FIG. 12 may include two curved segments, which are a first curved segment 1210 and a second curved segment 1220, respectively, and the first curved segment 1210 and the second curved segment 1220 are connected at their start points and end points to form the elastic element 1200. The first curved segment 1210 is curved in a first direction, and the second curved segment 1220 is curved in a second direction, and the first direction and the second direction are opposite to each other with respect to a reference line (shown by a dashed line in FIG. 12) of the elastic element 1200. In some embodiments, the first direction may be a counterclockwise direction relative to a geometric center of the projection of the elastic element in a projection plane along the axial direction of the piezoelectric element, and the second direction may be a clockwise direction relative to a geometric center of the projection of the elastic element in a projection plane along the axial direction of the piezoelectric element.

[0114] By setting the bending directions of adjacent curved segments among the multiple curved segments of the elastic element 1200 in opposite directions, the rotational modes of the adjacent curved segments during vibration can be cancelled out in opposite phases, thereby reducing or canceling the resonant valleys generated by the rotational modes.

[0115] Fig. 13A is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The structure of the vibration device 1300-1 shown in Fig. 13A is almost the same as the structure of the vibration device 200 shown in Fig. 2, but differs in that the structure of the elastic element is different.

[0116] As shown in FIG. 13A, in some embodiments, the elastic elements 1330 may be located in the same plane perpendicular to the axial direction of the first piezoelectric element 1311. For example, the elastic element 1330 may be a vibration transmission sheet or a vibration transmission rod structure, and the vibration transmission sheets are located in the same plane, and the plane is perpendicular to the axial direction of the ring structure. In some embodiments, the elastic elements 1330 may be arranged in a certain manner, and the projection of the arranged elastic elements 1330 along the axial direction of the first piezoelectric element 1311 may have at least two symmetric axes perpendicular to each other.

[0117] In some embodiments, the number of elastic elements 1330 connecting the mass element 1320 and the first piezoelectric element 1311 may be an even number (e.g., four, eight, etc.). As shown in FIG. 13A, in some embodiments, the number of elastic elements 1330 connecting the mass element 1320 and the first piezoelectric element 1311 may be four, and the four elastic elements may be arranged to form an X-shape. The bending directions of adjacent elastic elements among the four elastic elements may be opposite, and the bending directions of opposing elastic elements may be the same. When the four elastic elements 1330 are arranged in an X-shape, the projection of the four elastic elements 1330 along the axial direction of the first piezoelectric element 1311 may have two first and second symmetry axes 1301 and 1302 that are perpendicular to each other.

[0118] In some embodiments, in the X-shaped elastic element 1330, an included angle can be formed between a single elastic element and an axis of symmetry (e.g., the first axis of symmetry 1301 or the second axis of symmetry 1302), for example, an included angle θ can be formed between the elastic element and the first axis of symmetry 1301. By adjusting the angle of the included angle θ, the rolling modes along different axes of symmetry when the vibration device vibrates can be controlled. In some embodiments, the angle range of the included angle θ can be 10° to 30° to reduce the rolling modes as much as possible when the vibration device vibrates. In some embodiments, the angle range of the included angle θ can be 30° to 60° to reduce the rolling modes as much as possible when the vibration device vibrates. In some embodiments, the angle range of the included angle θ can be 60° to 80° to reduce the rolling modes as much as possible when the vibration device vibrates.

[0119] The structure and connection manner of the elastic element 1330 shown in FIG. 13A can be applied not only to the piezoelectric element with the ring structure described above, but also to piezoelectric elements with other structures. For example, FIG. 13B is an exemplary structural diagram of a vibration device shown in some embodiments of the present specification. The vibration device 1300-2 shown in FIG. 13B may include a piezoelectric element 1340, a first mass element 1351, a second mass element 1352, a connecting member 1341, and one or more elastic elements 1360. In some embodiments, the piezoelectric element 1340 may be constructed in a piezoelectric beam structure, and the second mass element 1352 may be connected to the middle part of the piezoelectric beam. In some embodiments, a piezoelectric sheet (the one surface or the one set of surfaces are also called piezoelectric surfaces) may be attached to one surface or a set of opposing surfaces of the piezoelectric beam, and the piezoelectric sheet can expand and contract based on an electric signal, so that the piezoelectric beam can generate a vibration perpendicular to the piezoelectric surface based on an electric signal. In some embodiments, the connecting members 1341 are provided at both ends of the piezoelectric beam, and the piezoelectric beam is connected to one end of the plurality of elastic elements 1360 by the connecting members 1341 at both ends. In some embodiments, the other ends of the plurality of elastic elements 1360 may be connected to the first mass element 1351. In some embodiments, the plurality of elastic elements 1360 may be distributed along the circumferential direction of the first mass element 1351. In some embodiments, the plurality of elastic elements 1360 may be located in the same plane, and the plane in which the elastic elements 1360 are located is parallel to the piezoelectric plane of the piezoelectric beam. The shape and structure of the plurality of elastic elements 1360 may be the same as the shape and structure of the elastic element 1330 shown in FIG. 13A. For example, the number of the plurality of elastic elements 1360 may be four, and the four elastic elements may be arranged to form an X-shape. When arranged in an X-shape, the four elastic elements 1330 may have an axis of symmetry 1301 and an axis of symmetry 1302, such that adjacent elastic elements among the four elastic elements 1330 may be curved in opposite directions.

[0120] Fig. 14A is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The structure of the vibration device 1400-1 shown in Fig. 14A is almost the same as the structure of the vibration device 1300-1 shown in Fig. 13A, but differs in that the number and structure of the elastic elements are different.

[0121] As shown in FIG. 14A, in some embodiments, the number of elastic elements 1430 connecting the mass element 1420 and the first piezoelectric element 1411 may be eight, and the eight elastic elements may form a double X-shape. Four of the eight elastic elements may form a first X-shape 1401, and the remaining four elastic elements may form a second X-shape 1402, and the first X-shape 1401 and the second X-shape 1402 may form a double X-shape structure of the multiple elastic elements 1430. In some embodiments, the double X-shape structure formed by the multiple elastic elements 1430 may be a parallel double X-shape, a perpendicular double X-shape (as shown in FIG. 14A), or other types of inversion symmetric shapes. The parallel / perpendicular double X-shape refers to the two symmetry axes of the first X-shape 1401 and the two symmetry axes of the second X-shape 1402 being parallel / perpendicular, respectively.

[0122] Fig. 14B is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The structure of the vibration device 1400-2 shown in Fig. 14B is almost the same as the structure of the vibration device 1300-2 shown in Fig. 13B, but differs in that the number of piezoelectric beams, the number and structure of elastic elements are different.

[0123] As shown in FIG. 14B, in some embodiments, the number of elastic elements 1460 connecting the mass element 1450 and the piezoelectric element 1440 may be eight, and the eight elastic elements 1460 are distributed along the circumferential direction of the first mass element 1451. In some embodiments, the eight elastic elements may form a double X-shape. Four of the eight elastic elements may form a first X-shape, and the remaining four elastic elements may form a second X-shape, and the first X-shape and the second X-shape may form a double X-shape structure of the multiple elastic elements 1460. In some embodiments, the double X-shape structure of the multiple elastic elements 1460 may be a parallel double X-shape (as shown in FIG. 14C), a perpendicular double X-shape (as shown in FIG. 14B), or other types of inversion symmetric shapes.

[0124] 14B, when the double X-shaped structure composed of multiple elastic elements 1460 is a vertical double X-shaped structure, the four elastic elements forming the first X-shaped are respectively connected to the same piezoelectric element of two piezoelectric elements 1440 (e.g., a piezoelectric beam structure) by connecting members 1441, and the four elastic elements forming the second X-shaped are respectively connected to another piezoelectric element, and the two piezoelectric elements are disposed perpendicular to each other in the same plane. The two piezoelectric elements 1440 may be simultaneously connected to a second mass element 1452.

[0125] FIG. 14C is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. As shown in FIG. 14C, the double X-shaped structure composed of multiple elastic elements 1460 is a parallel double X-shaped structure. The connection form between the elastic elements and the piezoelectric elements of the vibration device 1400-3 shown in FIG. 14C is almost the same as that of FIG. 14B. The four elastic elements 1460 forming the first X-shape are connected to one piezoelectric element 1440 (e.g., a piezoelectric beam structure) by a connecting member 1441, and the four elastic elements 1460 forming the second X-shape are connected to another piezoelectric element 1440 (e.g., a piezoelectric beam structure) by a connecting member 1441, and the two piezoelectric elements 1440 are placed parallel to each other in the same plane. The difference is that the four elastic elements 1460 forming the first X-shape and the four elastic elements 1460 forming the second X-shape are further connected to the first mass element 1451, respectively. In some embodiments, the first mass element 1451 may be one or more, and the multiple first mass elements 1451 may be connected to each other by a rigid connecting member (not shown). The two piezoelectric elements 1440 are each connected to a second mass element 1452. In some embodiments, the second mass element 1452 may be one or more, and the multiple second mass elements 1452 may be connected to each other by a rigid connecting member 1453.

[0126] In some embodiments, the vibration performance of the vibration device may be different when the shape structure of the elastic element is different. The higher the degree of inversion symmetry of the elastic element, the fewer the rotational modes caused by the vibration of the elastic element, and the higher the vibration performance of the vibration device. FIG. 14D is a frequency response curve diagram of a vibration device according to some embodiments herein. Curve 1401 may represent the frequency response curve of a vibration device (e.g., vibration device 1300-2) when the elastic element is a single X-shape, curve 1402 may represent the frequency response curve of a vibration device (e.g., vibration device 1400-3) when the elastic element is a parallel double X-shape, and curve 1403 may represent the frequency response curve of a vibration device (e.g., vibration device 1400-1 or vibration device 1400-2) when the elastic element is a non-parallel double X-shape. As can be seen from the curves 1401, 1402 and 1403, when the elastic element has a single X-shape, a parallel double X-shape and other types of double X-shape, the frequency response effect of the vibration device is high. Note that when the elastic element has a single X-shape, the curve 1401 generates a resonance valley near 1411Hz, and the resonance valley is not generated by the rotation mode of the elastic element, but is generated by the mass element connected to the piezoelectric element and the vibration system formed by the piezoelectric element absorbing the vibration of the output end. For example, as shown in FIG. 13B, the resonance valley may be generated by the vibration system formed by the second mass element 1352 and the piezoelectric beam 1340 absorbing the vibration of the first mass element 1351.

[0127] In some embodiments, the elastic element may be configured in a two-layer structure, and the two layers of elastic elements are distributed up and down along the axial direction of the ring structure. In some embodiments, the elastic element may include a first elastic element and a second elastic element disposed along the axial direction of the ring structure. The first elastic element and the second elastic element may be curved in opposite directions. For example, the first elastic element and the second elastic element have a plurality of curved segments curved in opposite directions.

[0128] In some embodiments, the shape of the elastic element set in two layers may be any one of two-layered bent-line, two-layered S-shape, two-layered spline curve, two-layered arc shape, etc. In some embodiments, the elastic element set in two layers is a first layer of a plurality of bent-line elastic elements arranged along a first direction, and a second layer of a plurality of bent-line elastic elements arranged along a second direction. The first direction and the second direction are opposite to the reference line direction of the elastic element.

[0129] In some embodiments, when the elastic element has a two-layer structure, the curvature directions of adjacent curved segments among a plurality of curved segments included in each of the elastic elements located in the same layer may be opposite to each other, and the curvature directions of two elastic elements located on different layer surfaces and opposite to each other along the axial direction of the ring-shaped structure may be opposite to each other.

[0130] Fig. 15A is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The structure of the vibration device 1500-1 shown in Fig. 15A is almost the same as the structure of the vibration device 200 shown in Fig. 2, but differs in that the structure of the elastic element is different.

[0131] 15A , the one or more elastic elements 1530 may include a first helical structure 1531 and a second helical structure 1532 connected to the mass element 1520 and the one or more piezoelectric elements 1510, respectively. In some embodiments, the first helical structure 1531 and the second helical structure 1532 may be arranged one above the other along the axial direction of the piezoelectric element 1510. The connection position between the first helical structure 1531 and the piezoelectric element 1510 may be on a side of the piezoelectric element 1510 that is close to the mass element 1520. The connection position between the second helical structure 1532 and the piezoelectric element 1510 may be on a side of the piezoelectric element 1510 that is away from the mass element 1520.

[0132] In some embodiments, the first helical structure 1531 and the second helical structure 1532 may have the same axis and opposite helical directions. The helical direction may be the direction in which the helical structure rotates about its axis. In some embodiments, at least two elastic elements 130 may rotate in opposite directions along the same axis to form the first helical structure 1531 and the second helical structure 1532 with opposite helical directions.

[0133] In some embodiments, the elastic element 1530 is configured as a double-layered helical structure, which can reduce the rotation width of the elastic element 1530 during the vibration process of the vibration device 1500. The double-layered helical structure can also increase the elastic coefficient of the elastic element 1530, so that the first resonance peak generated by the resonance of the elastic element 1530 and the mass element 1520 shifts to the right (i.e., shifts to a higher frequency), thereby meeting the vibration performance demands of the vibration device 1500-1.

[0134] Fig. 15B is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The double-layered spiral structure of the elastic element 1530 shown in Fig. 15A can also be applied to the vibration device 1500-2 shown in Fig. 15B. The structure of the vibration device 1500-2 shown in Fig. 15B is almost the same as the structure of the vibration device 1400-2 in Fig. 14B, but differs in that the structure of the elastic element is different.

[0135] 15B, in some embodiments, the elastic element 1560 may include a first helical structure 1561 and a second helical structure 1562 arranged vertically along a thickness direction of the first mass element 1551. The first helical structure 1561 and the second helical structure 1562 are respectively connected to the first mass element 1551 and the plurality of piezoelectric elements 1540. The first helical structure 1561 and the second helical structure 1562 have opposite helical directions.

[0136] In some embodiments, when the elastic element is a helical structure, the number of layers of the helical structure may be different, and the vibration performance of the corresponding vibration device may also be different. In some embodiments, the inversion symmetry of the double-layered helical structure is higher than that of the single-layered helical structure, so that the vibration performance of the vibration device in which the elastic element is a double-layered helical structure is higher than that of the vibration device in which the elastic element is a single-layered helical structure. FIG. 16 is an exemplary frequency response curve diagram of a vibration device according to some embodiments herein. Curve 1610 may represent the frequency response curve of the vibration device in which the elastic element is a single-layered helical structure, and curve 1620 may represent the frequency response curve of the vibration device in which the elastic element is a double-layered helical structure. As can be seen by comparing the curves 1610 and 1620, the peak value of the resonance valley formed in the frequency response curve 1620 of the vibration device in which the elastic element is a double-layered helical structure is obviously higher than that in which the elastic element is a single-layered helical structure.

[0137] 17 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. As shown in FIG. 17, the vibration device 1700 may include one or more piezoelectric elements 1710, a mass element 1720, and one or more elastic elements 1730. The one or more piezoelectric elements 1710 include a first piezoelectric element 1711 and a second piezoelectric element 1712 located inside a first ring-shaped structure of the first piezoelectric element 1711. The mass element 1720 is located inside a second ring-shaped structure of the second piezoelectric element 1712.

[0138] In some embodiments, the one or more elastic elements 1730 may include one or more inner ring elastic elements 1732 and one or more outer ring elastic elements 1731. In some embodiments, the one or more inner ring elastic elements 1732 and the one or more outer ring elastic elements 1731 may have opposite curvature directions. For example, the inner ring elastic element 1732 and the outer ring elastic element 1731 may be S-shaped in shape, with the S-shaped curvature directions being opposite.

[0139] In some embodiments, when the inner ring elastic element 1732 and the outer ring elastic element 1731 have opposite curvature directions, the rotational modes generated by the inner ring elastic element 1732 and the outer ring elastic element 1731 during the vibration process of the vibration device 1700 may be opposite, and thereby cancel (or attenuate) each other, thereby overall reducing the rotational modes during the vibration process of the vibration device 1700.

[0140] Fig. 18 is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The vibration device 1800 shown in Fig. 18 has a structure similar to that of the vibration device 1700 shown in Fig. 17, but the shape of the elastic element is different. The elastic element 1830 of the vibration device 1800 has a circular arc shape. The inner ring elastic element 1832 and the outer ring elastic element 1831 have opposite curvature directions of the circular arc shape.

[0141] In some embodiments, when the one or more elastic elements include one or more inner ring elastic elements and one or more outer ring elastic elements, the shape of the inner / outer ring elastic elements may not be limited to an S-shape and an arc shape, and may be other shapes, such as a broken line, a spline curve shape, etc.

[0142] 19 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. As shown in FIG. 19, the vibration device 1900 may include one or more piezoelectric elements 1910, a mass element 1920, and one or more elastic elements 1930. In some embodiments, the one or more piezoelectric elements 1910 may include two first piezoelectric elements 1911 that are distributed vertically along an axial direction and connected to each other. The two first piezoelectric elements 1911 are distributed vertically along an axial direction to form a two-layer single ring structure of the piezoelectric element 1910.

[0143] In some embodiments, the mass element 1920 may be connected to the two first piezoelectric elements 1911 by one or more elastic elements 1930, respectively. In some embodiments, the one or more elastic elements 1930 may be configured in two layers, and the two-layer elastic element 1930 includes two layers of first elastic elements 1931 arranged up and down along the axial direction of the piezoelectric element 1910. In some embodiments, the two layers of first elastic elements 1931 may be connected in the circumferential direction of the two first piezoelectric elements 1911, respectively. The mass element 1920 is connected to the two piezoelectric elements 1911 by the two layers of first elastic elements 1931, respectively. In some embodiments, the two layers of first elastic elements 1931 may have opposite curvature directions.

[0144] In some embodiments, when the number of first piezoelectric elements 1911 is two, the two first piezoelectric elements 1911 may have opposite changes in displacement along the axial direction during the vibration process. That is, one of the two first piezoelectric elements 1911 has a larger displacement along the axial direction (i.e., expands) during the vibration process, and the other has a smaller displacement along the axial direction (i.e., contracts) during the vibration process. In some embodiments, the change in the displacement along the axial direction of the first piezoelectric element 1911 during the vibration process may be adjusted by the polarization direction of the first piezoelectric element 1911 and the electrode polarity of the electric signal. For details, see the relevant description of Figures 20A and 20B in this specification.

[0145] In some embodiments, the number of first piezoelectric elements 1911 included in the piezoelectric element 1910 may be multiple, for example, four, six, eight, etc. The multiple first piezoelectric elements 1911 may be connected in sequence along the axial direction, and the mass elements 1920 are connected to each of the multiple first piezoelectric elements 1911 by multiple elastic elements 1930 (e.g., divided into multiple layers). In some embodiments, the number of mass elements 1920 may be multiple, and each of the multiple mass elements 1920 may be connected to one first piezoelectric element 1911 by multiple elastic elements 1930.

[0146] FIG. 20A is an exemplary circuit diagram of a first piezoelectric element according to some embodiments of the present disclosure. As shown in FIG. 20A, the polarity of the connection surfaces of the two first piezoelectric elements 1911 may be the same, and the electrode polarity of the electrical signals on the connection surfaces may be the same. For ease of explanation, the two first piezoelectric elements 1911 may be referred to as an upper layer piezoelectric element 19111 and a lower layer piezoelectric element 19112, respectively. In some embodiments, when the upper layer piezoelectric element 19111 is connected to the lower layer piezoelectric element 19112, the upper layer piezoelectric element 19111 may have an upper layer connection surface 2010, and the lower layer piezoelectric element 19112 may have a lower layer connection surface 2020. In some embodiments, when the upper layer piezoelectric element 19111 and the lower layer piezoelectric element 19112 have the same polarization direction (as shown by the arrow in FIG. 20A), the upper layer connection surface 2010 and the lower layer connection surface 2020 may have the same electrode polarity (e.g., positive or negative) of the applied electrical signal. In such a setting method, the upper layer piezoelectric element 19111 and the lower layer piezoelectric element 19112 may have opposite internal potential directions.

[0147] By setting the polarization direction of the upper layer piezoelectric element 19111 and the lower layer piezoelectric element 19112 to the same direction, when an opposite electric potential (or electrical signal) is applied to the upper layer piezoelectric element 19111 and the lower layer piezoelectric element 19112, the upper layer piezoelectric element 19111 and the lower layer piezoelectric element 19112 can be displaced in opposite directions.

[0148] FIG. 20B is another exemplary circuit diagram of the first piezoelectric element according to some embodiments of the present specification. As shown in FIG. 20B, the polarity of the connection surfaces of the two first piezoelectric elements may be reversed, and the electrode polarity of the electric signals on the connection surfaces may be reversed. In some embodiments, when the upper layer piezoelectric element 19113 is connected to the lower layer piezoelectric element 19114, the upper layer piezoelectric element 19113 may have an upper layer connection surface 2030, and the lower layer piezoelectric element 19114 may have a lower layer connection surface 2040. When the upper layer piezoelectric element 19113 and the lower layer piezoelectric element 19114 have opposite polarization directions (as shown by the arrows in FIG. 20B), the upper layer connection surface 2030 and the lower layer connection surface 2040 may have opposite electrode polarities (e.g., positive or negative) of the applied electric signals. In such a setting manner, the upper layer piezoelectric element 19113 and the lower layer piezoelectric element 19114 may have the same internal electric potential direction.

[0149] By setting the polarization directions of the upper layer piezoelectric element 19113 and the lower layer piezoelectric element 19114 to be opposite, when a potential (or electrical signal) in the same direction is applied to the upper layer piezoelectric element 19113 and the lower layer piezoelectric element 19114, the upper layer piezoelectric element 19113 and the lower layer piezoelectric element 19114 can be displaced in opposite directions.

[0150] Fig. 21 is an exemplary structural diagram of a vibration device according to some embodiments of the present specification. The structure of the vibration device 2100 shown in Fig. 21 is similar to the structure of the vibration device 500 shown in Fig. 5, but differs in that the structure of the piezoelectric element is different. The piezoelectric element 510 of the vibration device 500 is a single-layer double ring structure, and the piezoelectric element 2110 of the vibration device 2100 is a two-layer double ring structure.

[0151] 21, in some embodiments, the one or more piezoelectric elements 2110 may include two first piezoelectric elements 2111 that are vertically distributed along an axial direction and connected to each other, and two second piezoelectric elements 2112 that are located inside the first ring-shaped structure and vertically distributed along an axial direction and connected to each other. The axes of the two second piezoelectric elements 2112 can overlap with the axes of the two first piezoelectric elements 2111, and the projections of the two second piezoelectric elements 2112 along the axial direction are within the projections of the two first piezoelectric elements 2111 along the axial direction of the first ring-shaped structure.

[0152] In some embodiments, the two second piezoelectric elements 2112 may be connected to the two first piezoelectric elements 2111 by at least one of one or more elastic elements. In some embodiments, the elastic element may include an outer ring elastic element 2132 located between the first ring structure and the second ring structure. The outer ring elastic element 2132 may include two elastic elements, and the two first piezoelectric elements 2111 and the two second piezoelectric elements 2112 are respectively connected by the two elastic elements of the outer ring elastic element 2132. In some embodiments, the outer ring elastic element 2132 may have a constant thickness along the axial direction of the second ring structure, and the two first piezoelectric elements 2111 and the two second piezoelectric elements 2112 may be connected by one outer ring elastic element 2132.

[0153] In some embodiments, as shown in FIG. 21, the mass element 2120 may be located inside the second ring-shaped structure of the second piezoelectric element 2112 (as shown in FIG. 21). The axial projection of the mass element 2120 is within the axial projection of the second piezoelectric element 2112. The mass element 2120 may be connected to the two second piezoelectric elements 2112 by at least one of the one or more elastic elements 2130, respectively. For example, the elastic element 2130 may include an inner ring elastic element 2131 located between the second ring-shaped structure and the mass element 2120. The inner ring elastic element 2131 may include two elastic elements arranged along the axial direction, and the mass element 2120 is connected to the two second piezoelectric elements 2112 by the two elastic elements of the inner ring elastic element 2131, respectively. In some embodiments, the inner ring elastic element 2131 may have a constant thickness along the axial direction of the first ring structure, and the mass element 2120 and the two second piezoelectric elements 2112 may be connected by one inner ring elastic element 2131.

[0154] In some embodiments, when the mass element 2120 is located inside the second piezoelectric element 2112, one axial end of the first piezoelectric element 2111 may be fixed, and the other end may be connected to the second piezoelectric element 2112 by the outer ring elastic element 2132. For example, the outer ring elastic element 2132 may include two elastic elements arranged along the axial direction, and the two first piezoelectric elements 2111 are respectively connected to the two second piezoelectric elements 2112 by the two elastic elements of the outer ring elastic element 2132. In this case, the second piezoelectric element 2112 may be a piezoelectric free ring, and the first piezoelectric element 2111 may be a piezoelectric fixed ring.

[0155] In some embodiments, the mass element 2120 may also be located outside the first ring-shaped structure of the first piezoelectric element 2111. The axial projection of the mass element 2120 is other than the axial projection of the first piezoelectric element 2121. The mass element 2120 may be connected to the two first piezoelectric elements 2111 respectively by at least one of the one or more elastic elements 2130. For example, the mass element 2120 may be connected to the two first piezoelectric elements 2111 respectively by two elastic elements of the outer ring elastic element 2132.

[0156] In some embodiments, when the mass element 2120 is located outside the first piezoelectric element 2111, one end along the axis of the second piezoelectric element 2112 may be fixed, and the other end may be connected to the first piezoelectric element 2111 by the inner ring elastic element 2131. In this case, the second piezoelectric element 2112 may be a piezoelectric fixed ring, and the first piezoelectric element 2111 may be a piezoelectric free ring.

[0157] In some embodiments, the mass element 2120 may also be located between the first ring structure of the first piezoelectric element 2111 and the second ring structure of the second piezoelectric element 2112. The axial projection of the mass element 2120 is between the axial projections of the first piezoelectric element 2111 and the second piezoelectric element 2112. The mass element 2120 may be connected to the two first piezoelectric elements 2111 and the two second piezoelectric elements 2112 by one or more elastic elements 2130, respectively. For example, the mass element 2120 may be connected to the two first piezoelectric elements 2111 by an outer ring elastic element 2132, respectively, and connected to the two second piezoelectric elements 2112 by an inner ring elastic element 2131, respectively.

[0158] In some embodiments, when the mass element 2120 is located between the second piezoelectric element 2112 and the first piezoelectric element 2111, either the first piezoelectric element 2111 or the second piezoelectric element 2112 has a fixed end along the axial direction. In this case, one of the first piezoelectric element 2111 and the second piezoelectric element 2112 may be a piezoelectric free ring and the other may be a piezoelectric fixed ring.

[0159] In addition, when the piezoelectric element 2110 has a two-layer structure, it does not need to have a fixed end along the axial direction, so the vibration device 2100 is more convenient to use in bone conduction earphones, where it is difficult to find a strict fixed boundary.

[0160] In some embodiments, by installing the first piezoelectric element 2111 and the second piezoelectric element 2112 in the vibration device 2100, the mass element 2120 and the second piezoelectric element 2112 can form an entire mass, and since the entire mass is larger than the mass of the mass element 2120, the first resonance peak of the vibration device 2100 is shifted to a lower frequency. When the vibration device 2100 vibrates, a third resonance peak between the first resonance peak and the second resonance peak can be generated by resonance of a double ring structure formed by connecting the first piezoelectric element 2111 and the second piezoelectric element 2112 to each other by the outer ring elastic element 2132, and it can be expressed as additionally forming another resonance peak, i.e., the third resonance peak, at a position between the first resonance peak and the second resonance peak in the frequency response curve of the vibration device 2100. In some embodiments, the third resonance frequency corresponding to the third resonance peak may be between the first resonance frequency corresponding to the first resonance peak and the second resonance frequency corresponding to the second resonance peak.

[0161] It should be noted that, when the piezoelectric element 2110 has a two-layer structure, the elastic element may have a two-layer structure, and the bending directions of the two layers of the elastic element in the two-layer structure of the elastic element may be opposite. In some embodiments, the piezoelectric element may have a multi-layer polycyclic structure, such as a four-layer four-ring structure. The piezoelectric element with the multi-layer polycyclic structure is similar to the piezoelectric element with the two-layer two-ring structure, and the description thereof is omitted here.

[0162] FIG. 22 is a frequency response curve diagram of a vibration device according to some embodiments of the present disclosure. Curve 2210 may represent a frequency response curve of a vibration device (e.g., vibration device 1900) when the piezoelectric element is a two-layer single ring structure, and curve 2220 may represent a frequency response curve of a vibration device (e.g., vibration device 2100) when the piezoelectric element is a single-layer double ring structure and the first piezoelectric element has a fixed end along the axial direction. In some embodiments, a third resonance peak other than the first and second resonance peaks can be formed in the frequency response curve of the vibration device by installing a piezoelectric free ring in the vibration device. For example, comparing curve 2210 and curve 2220, a third resonance peak other than the first and second resonance peaks can be formed in curve 2220, and the frequency of the third resonance peak is between the frequency of the first resonance peak and the frequency of the second resonance peak.

[0163] 22, curve 2230 represents the frequency response curve of a vibration device in which the piezoelectric element is a two-layer double ring structure and the first piezoelectric element has a fixed end along the axial direction, and curve 2240 represents the frequency response curve of a vibration device in which the piezoelectric element is a two-layer double ring structure and the piezoelectric element does not have a fixed end along the axial direction. In some embodiments, the sensitivity of the vibration device in the frequency range of the audible band can be improved by installing the piezoelectric element in a two-layer anti-phase vibration structure. For example, comparing curve 2220 and curve 2230, curve 2230 is offset upwards as a whole from curve 2220, and has a higher sensitivity than that of curve 2220. In some embodiments, by installing both the first piezoelectric element and the second piezoelectric element in the form of a free ring, the first piezoelectric element and the second piezoelectric element (and the connecting elastic element) together with the mass element constitute a whole mass, so that the low-frequency resonance peak of the vibration device is shifted to the right. For example, comparing curves 2230 and 2240, the first resonant peak of curve 2240 is offset to the right relative to the first resonant peak of curve 2230, thereby improving high frequency performance.

[0164] In some embodiments, when the piezoelectric elements are set in a two-layer structure, the structures of the two layers of piezoelectric elements may be the same. For example, the piezoelectric element may include two first piezoelectric elements arranged in sequence along the axial direction, and the structures of the two piezoelectric elements are both ring-shaped structures. In some embodiments, when the piezoelectric elements are set in a two-layer structure, the structures of the two layers of piezoelectric elements may be different. For example, the piezoelectric element of one layer of the two layers of piezoelectric elements may have a ring-shaped structure, and the piezoelectric element of the other layer has a piezoelectric beam structure.

[0165] FIG. 23 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. As shown in FIG. 23, the vibration device 2300 may include one or more piezoelectric elements 2310, a mass element 2320, and one or more elastic elements 2330, as well as a piezoelectric beam 2340. The piezoelectric beam 2340 may be configured to generate vibration along an axial direction of the ring-shaped structure of the piezoelectric element 2310 based on an electric signal. In some embodiments, the piezoelectric beam 2340 may be connected to the mass element 2320. In some embodiments, the piezoelectric beam 2340 may be located on a side of the mass element 2320 away from the piezoelectric element 2310 along an axial direction of the ring-shaped structure of the piezoelectric element 2310 and connected to the mass element 2320. In some embodiments, the piezoelectric beam 2340 may be a plate-like structure, and a plate surface (i.e., a surface having a largest area) of the plate-like structure is placed parallel to an annular end surface of the ring-shaped structure of the piezoelectric element 2310.

[0166] In some embodiments, the piezoelectric beam 2340 may include at least one first piezoelectric sheet 2341 and at least one second piezoelectric sheet 2342. The at least one first piezoelectric sheet 2341 and the at least one second piezoelectric sheet 2342 are disposed on both sides of the piezoelectric beam 2340 along the axis of the ring-shaped structure of the piezoelectric element 2310. For example, the first piezoelectric sheet 2341 may be disposed on a side of the piezoelectric beam 2340 that is farther away from the piezoelectric element 2310 along the axis of the piezoelectric beam 2340, and the second piezoelectric sheet 2342 is disposed on a side of the piezoelectric beam 2340 that is closer to the piezoelectric element 2310 along the axis of the piezoelectric beam 2340.

[0167] In some embodiments, the first piezoelectric sheet 2341 and the second piezoelectric sheet 2342 may be set to have opposite polarization directions along the axis of the ring structure. That is, the first piezoelectric sheet 2341 and the second piezoelectric sheet 2342 have opposite polarization directions along the axis of the ring structure of the piezoelectric element 2310. The first piezoelectric sheet 2341 and the second piezoelectric sheet 2342 may have a displacement output direction perpendicular to their respective polarization directions. In some embodiments, when the first piezoelectric sheet 2341 and the second piezoelectric sheet 2342 are set to have opposite polarization directions and voltage signals of the same direction are simultaneously applied, the first piezoelectric sheet 2341 and the second piezoelectric sheet 2342 can generate displacements in opposite directions, so that the piezoelectric beam 2340 generates vibration. For example, the first piezoelectric sheet 2341 can contract along an axial direction perpendicular to the ring structure, and the second piezoelectric sheet 2342 can expand along an axial direction perpendicular to the ring structure, so that the piezoelectric beam 2340 can generate vibration along the axial direction of the ring structure. In some embodiments, the piezoelectric beam 2340 can be connected to the mass element 2320 and output vibration by the mass element 2320. In some embodiments, the piezoelectric beam 2340 can be directly connected to the mass element 2320, so that the resonant peak of the vibration device 2300 includes a high frequency resonant peak (e.g., in a frequency range of 2 kHz to 20 kHz) generated by the resonance of the piezoelectric beam 2340, i.e., the piezoelectric beam 2340 constitutes a high frequency unit of the vibration device 2300.

[0168] In some embodiments, the structure of the elastic element 2330 of the vibration device 2300 may be a double X-shaped structure as shown in FIG. 23, or may be other structure types with inversion symmetry, such as a single X-shaped, parallel double X-shaped, a helical structure, etc.

[0169] Fig. 24 is an exemplary structural diagram of a vibration device according to some embodiments of the present disclosure. The structure of vibration device 2400 in Fig. 24 is almost the same as that of vibration device 2300 in Fig. 23, but differs in the structure and number of mass elements, and the manner of connection between the mass elements and the piezoelectric beam.

[0170] As shown in FIG. 24, in some embodiments, the mass element may include a first mass element 2421 and a second mass element 2422. The first mass element 2421 may be connected to a middle part of the piezoelectric beam 2340 by one or more elastic elements 2330. In some embodiments, the first mass element 2421 may be connected to one or more piezoelectric elements 2310 by the elastic elements 2330, where the piezoelectric elements 2310 include a ring-shaped structure and the vibration direction is parallel to the axial direction of the ring-shaped structure. In some embodiments, the second mass elements 2422 may be connected to both ends of the piezoelectric beam 2340, respectively. The vibration of the vibration device 2400 may be output by the second mass element 2422 at the end of the piezoelectric beam 2340. In some embodiments, the vibration of the vibration device 2400 may also be output by the first mass element 2421. In some embodiments, the first mass element 2421 of the vibration device 2400 may be connected to the piezoelectric beam 2340 by one or more elastic elements 2330 to form a low-frequency unit of the vibration device 2400, and the piezoelectric element 2310 having a ring-shaped structure may form a high-frequency unit of the vibration device 2400.

[0171] In some embodiments, the first mass element 2421 may be connected to another location on the piezoelectric beam 2340 (e.g., proximate an end of the piezoelectric beam 2340) by one or more elastic elements 2330. In some embodiments, both ends of the piezoelectric beam 2340 may be connected to the second mass element 2422 by one or more elastic elements 2330.

[0172] Although the basic concept has been described above, it is clear to those skilled in the art that the detailed disclosure above is merely provided as an example and does not limit the present application. Although not explicitly described herein, those skilled in the art may make various changes, improvements and modifications to the present application. These changes, improvements and modifications are intended to be suggested by the present application and therefore are within the spirit and scope of the exemplary embodiments of the present application.

[0173] Also, certain terms are used herein to describe embodiments of the present application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the present application. Thus, it is emphasized and understood that references to "one embodiment," "one embodiment," or "one alternative embodiment" more than once in various parts of this specification do not necessarily all refer to the same embodiment. Also, certain features, structures, or characteristics of one or more embodiments of the present application may be combined as appropriate.

[0174] Also, as will be appreciated by those skilled in the art, aspects of the present application may be illustrated and described in several patentable classes or contexts, including any new and useful process, machine, manufacture, or combination of matter, or any new and useful improvement thereto. Thus, aspects of the present application may be implemented entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or a combination of hardware and software. Any of the above hardware or software may be referred to as a "data block," "module," "engine," "unit," "assembly," or "system." Also, aspects of the present application may take the form of a computer program product embodied in one or more computer-readable medium(s) containing computer-readable program code.

[0175] The computer storage medium may include a propagated data signal, propagated on baseband or as part of a carrier wave, for carrying the computer program code. The propagated signal may include various forms, such as electromagnetic signals, optical signals, or suitable combinations. The computer storage medium may be any computer readable medium other than a computer readable storage medium, which may be connected to an instruction execution system, device, or equipment to realize the communication, propagation, or transmission of the program used. The program code on the computer storage medium may be propagated via any suitable medium, including wireless, cable, fiber optic cable, RF, or similar media, or any combination of the above-mentioned media.

[0176] The computer program code necessary for the operation of each part of this application may be coded in one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python, traditional procedural programming languages ​​such as C, Visual Basic, Fortran 2003, Perl, COBOL 2002, PHP, ABAP, dynamic programming languages ​​such as Python, Ruby and Groovy, or other programming languages. The program code may be executed entirely on the user's computer, may be executed as a separate software package on the user's computer, may be executed partly on the user's computer and partly on a remote computer, or may be executed entirely on a remote computer or server. In the latter case, the remote computer may be connected to the user's computer by any form of network, such as a local area network (LAN) or wide area network (WAN), may be connected to an external computer (e.g., via the Internet), may be in a cloud computing environment, may be used as a service, such as Software as a Service (SaaS).

[0177] Additionally, unless expressly stated in each claim, the order of enumeration of processing elements or sequences described herein, the use of alphanumeric characters, or the use of other designations, do not limit the order of steps and methods of the present application. While the above disclosure has described through various examples what are presently believed to be various useful embodiments of the invention, it should be understood that such details are merely illustrative and that the appended claims are not limited to the disclosed embodiments, but on the contrary are intended to cover all modifications and equivalent combinations within the spirit and scope of the embodiments of the present application. For example, the system assembly described above may be implemented by a hardware device, but may also be implemented as a software-only solution, for example, by installing the described system on an existing server or mobile device.

[0178] Similarly, in the foregoing description of embodiments of the present application, it should be understood that various features may be grouped together in a single embodiment, drawing, or description for the purpose of streamlining the disclosure and facilitating an understanding of one or more embodiments of the present invention. This method of disclosure, however, should not be interpreted as reflecting an intention that the claimed subject matter requires more features than are recited in each claim. In fact, an embodiment may include fewer than all features of a single embodiment disclosed above.

[0179] In some embodiments, numbers describing the number of components and attributes are used, and it is understood that the numbers describing such embodiments are modified in some instances by the modifiers "about," "approximately," or "generally." Unless otherwise specified, "about," "approximately," or "generally" indicate that the numbers are allowed to vary by ±20%. Thus, in some embodiments, all numerical parameters used in the specification and claims are approximations that may vary depending on the characteristics required for a particular embodiment. In some embodiments, the numerical parameters should be applied with the stated number of significant digits and ordinary rounding techniques. In some embodiments, the numerical ranges and parameters determining the ranges are approximations; however, in specific embodiments, such numerical values ​​are set as precisely as possible.

[0180] All patents, patent applications, published patent applications, and other materials, such as articles, books, specifications, publications, documents, etc., referenced in this application are incorporated herein by reference in their entirety, except for prosecution history documents that are inconsistent or inconsistent with the content of this application, and documents that may have a limiting effect on the broadest scope of the claims of this application (now or later related to this application). In addition, if the explanations, definitions, and / or use of terms in the accompanying materials of this application are inconsistent or inconsistent with the content set forth in this application, the explanations, definitions, and / or use of terms in this application shall control.

[0181] Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present application. Other variations may be within the scope of the present application. Thus, by way of example, and not of limitation, alternative configurations of the embodiments of the present application may be considered consistent with the teachings of the present application. Thus, the embodiments of the present application are not limited to the embodiments expressly introduced and described herein. [Explanation of symbols]

[0182] 100 Vibration device 110 Piezoelectric element 120 Mass Element 130 Elastic element 200 Vibration device 210 Piezoelectric element 211 First piezoelectric element 220 Mass Element 230 Elastic element 310 First resonance peak 320 Second resonance peak 400 Vibration device 411 First Piezoelectric Element 420 Mass Element 430 Elastic elements 401 First resonance peak 402 Second resonance peak 500 vibration device 610 curve 620 curve 630 curve 640 curve 650 curve 603 3rd resonance peak 604 Resonance Valley 1020 Frequency Response Curve 1210 First curved segment 1220 Second curved segment 1301 First axis of symmetry 1302 Second axis of symmetry 1341 Connection parts 1531 First spiral structure 1532 Second spiral structure

Claims

1. A mass element; one or more piezoelectric elements configured to generate vibrations based on an electrical signal; one or more elastic elements, at least one of which is connected to the mass element and the one or more piezoelectric elements; Including, The one or more piezoelectric elements include a ring-shaped structure and are configured such that a direction of vibration based on an electrical signal is parallel to an axial direction of the ring-shaped structure; A vibration device, wherein at least one of the one or more elastic elements and the mass element resonate to produce a first resonant peak, and the one or more piezoelectric elements resonate to produce a second resonant peak.

2. 2. The vibration device of claim 1, wherein the one or more piezoelectric elements include a first piezoelectric element having one end along an axial direction fixed, and the mass element is connected to a position other than the one end of the first piezoelectric element by at least one of the one or more elastic elements.

3. The vibration device of claim 2 , wherein a projection of the mass element along the axis of the first piezoelectric element is within a projection of the first piezoelectric element along the axis of the first piezoelectric element.

4. The vibration device of claim 2 , wherein the mass element is ring-shaped and the projection of the mass element along the axis of the first piezoelectric element is other than the projection of the mass element along the axis of the first piezoelectric element.

5. The vibration device according to claim 2 , wherein the number of elastic elements connecting the mass element and the first piezoelectric element is multiple, and the multiple elastic elements are distributed along a circumferential direction of the ring structure.

6. The vibration device according to claim 1 , wherein the shape of the one or more elastic elements includes at least one of a broken line, an S-shape, a spline curve shape, a circular arc shape, and a straight line shape.

7. The vibration device according to claim 6 , wherein each of the one or more elastic elements has a plurality of curved portions, the curved portions being curved in opposite directions.

8. 2. The vibration device of claim 1, wherein the one or more elastic elements include a first helical structure and a second helical structure respectively connected to the mass element and the one or more piezoelectric elements, the first helical structure and the second helical structure having the same axis and opposite helical directions.

9. 2. The vibration device of claim 1, wherein the one or more piezoelectric elements include a first piezoelectric element including a first ring-shaped structure and a second piezoelectric element including a second ring-shaped structure, the second piezoelectric element being positioned inside the first ring-shaped structure.

10. 10. The vibration device of claim 9, wherein one end of the first piezoelectric element along the axial direction is fixed, the second piezoelectric element is connected to a position other than the one end of the first piezoelectric element by at least one of the one or more elastic elements, a projection of the mass element along the axial direction is within a projection of the second piezoelectric element along the axial direction, and the mass element is connected to the second piezoelectric element by at least another one of the one or more elastic elements.

11. 10. The vibration device of claim 9, wherein one end of the second piezoelectric element along the axial direction is fixed, the first piezoelectric element is connected to a position other than the one end of the second piezoelectric element by at least one of the one or more elastic elements, the shape of the mass element is ring-shaped, a projection of the mass element along the axial direction is other than a projection of the first piezoelectric element along the axial direction, and the mass element is connected to the first piezoelectric element by at least another one of the one or more elastic elements.

12. 10. The vibration device of claim 9, wherein the shape of the mass element is ring-shaped, the projection of the mass element along the axial direction is between the projections of the first and second piezoelectric elements along the axial direction, the mass element is connected to the first piezoelectric element by at least one of the one or more elastic elements, and the mass element is connected to the second piezoelectric element by at least another of the one or more elastic elements.

13. The vibration device of claim 1 , wherein the one or more piezoelectric elements include at least two first piezoelectric elements, and the at least two first piezoelectric elements are connected to each other along an axial direction.

14. The vibration device of claim 1 , further comprising a piezoelectric beam configured to generate vibration along an axis of the annular structure based on an electrical signal, the piezoelectric beam being connected to the mass element.

Images