Piezoelectric loudspeaker

Abstract

The invention belongs to the technical field of sound production devices, and discloses a piezoelectric loudspeaker, which comprises a support frame, a circuit assembly, a first diaphragm assembly, a second diaphragm assembly and a vibration assembly, and is characterized in that the periphery of the first diaphragm assembly is fixedly connected to the support frame, and the periphery of the second diaphragm assembly is fixedly connected to the support frame; the vibration assembly is arranged in the cavity, is located between the first vibrating diaphragm assembly and the second vibrating diaphragm assembly and comprises a first piezoelectric structure and a second piezoelectric structure which are arranged on the supporting frame in the same layer, and the first piezoelectric structure is fixedly connected to the first vibrating diaphragm assembly and used for driving the first vibrating diaphragm assembly to vibrate in the first direction; the second piezoelectric structure is fixedly connected to the second vibrating diaphragm assembly and is used for driving the second vibrating diaphragm assembly to vibrate along the first direction. The piezoelectric loudspeaker provided by the invention is small in thickness and lighter and thinner.

Description

Technical Field

[0001] The present invention relates to the technical field of sound-generating devices, and in particular to a piezoelectric speaker. Background Art

[0002] As an important electroacoustic device, speakers are widely used in electronic devices. Speakers can be divided into dynamic speakers, moving iron speakers and piezoelectric speakers according to their technical types. Compared with dynamic speakers, piezoelectric speakers have the advantages of being small, thin, light and free of magnetic field interference.

[0003] In the prior art, a piezoelectric speaker includes a piezoelectric sheet and a diaphragm stacked with the piezoelectric sheet. The piezoelectric sheet vibrates under the drive of a driving voltage, driving the diaphragm to vibrate, so as to realize the sound of the speaker. In order to improve the sound effect of the speaker, two diaphragms are usually provided, and the two diaphragms are arranged opposite to each other in the thickness direction of the piezoelectric speaker. In order to realize the driving of each diaphragm, two piezoelectric sheets are usually provided, and the two piezoelectric sheets are arranged between the two diaphragms at intervals, and are connected to the two diaphragms one by one. However, since the piezoelectric speaker includes two piezoelectric sheets, the piezoelectric speaker in the prior art is relatively thick, and there is a need for improvement. Summary of the invention

[0004] The first object of the present invention is to provide a piezoelectric speaker that is thinner and lighter.

[0005] As conceived above, the technical solution adopted by the present invention is:

[0006] Piezoelectric speakers, including:

[0007] A support frame, wherein the support frame forms a cavity extending through the upper surface and the lower surface;

[0008] A circuit assembly is arranged on the supporting frame;

[0009] A first diaphragm assembly, wherein the periphery of the first diaphragm assembly is fixedly connected to the supporting frame;

[0010] A second diaphragm assembly is arranged opposite to the first diaphragm assembly in a first direction, and a periphery of the second diaphragm assembly is fixedly connected to the support frame;

[0011] A vibration component is arranged in the cavity and is located between the first diaphragm component and the second diaphragm component, and the vibration component includes a first piezoelectric structure and a second piezoelectric structure arranged in the same layer on the support frame; the first piezoelectric structure and the second piezoelectric structure are both electrically connected to the circuit component; the first piezoelectric structure is fixedly connected to the first diaphragm component, and is used to drive the first diaphragm component to vibrate along the first direction; the second piezoelectric structure is fixedly connected to the second diaphragm component, and is used to drive the second diaphragm component to vibrate along the first direction.

[0012] Optionally, the vibration assembly further includes a first connecting member, wherein the first connecting member is connected between the first piezoelectric structure and the first diaphragm assembly;

[0013] and / or,

[0014] The vibration assembly also includes a second connecting member, which is connected between the second piezoelectric structure and the second diaphragm assembly.

[0015] Optionally, there are multiple first piezoelectric structures, and the vibration assembly also includes a first connecting member, which is connected to the first diaphragm assembly; there is one first connecting member, and all the first piezoelectric structures are connected to the first connecting member to be connected to the first diaphragm assembly through the first connecting member; or, there are multiple first connecting members, and each of the first connecting members is connected to at least one first piezoelectric structure.

[0016] Optionally, there are multiple second piezoelectric structures, and the vibration assembly also includes a second connecting member, which is connected to the second diaphragm assembly; there is one second connecting member, and all the second piezoelectric structures are connected to the second connecting member to be connected to the second diaphragm assembly through the second connecting member; or, there are multiple second connecting members, and each second connecting member is connected to at least one second piezoelectric structure.

[0017] Optionally, the first piezoelectric structure has a first free end and a first fixed end opposite to each other in a second direction, the first fixed end is connected to one end of the support frame, and the first free end is fixedly connected to the first diaphragm assembly; the second piezoelectric structure has a second free end and a second fixed end opposite to each other in the second direction, the second fixed end is connected to the other end of the support frame, and the second free end is fixedly connected to the second diaphragm assembly; wherein the first direction is perpendicular to the second direction.

[0018] Optionally, the orthographic projections of the first piezoelectric structure and the second piezoelectric structure in a third direction at least partially overlap; wherein the third direction is perpendicular to both the first direction and the second direction.

[0019] Optionally, multiple first piezoelectric structures are arranged along a third direction, and at least one second piezoelectric structure is provided. Two adjacent first piezoelectric structures in the third direction and one or more second piezoelectric structures form a piezoelectric group. In one piezoelectric group, the second free ends of one or more second piezoelectric structures are located between the two first piezoelectric structures in the third direction.

[0020] Optionally, the vibration assembly includes a first connecting member; in one of the piezoelectric groups, two of the first piezoelectric structures are connected to the same first connecting member, the first connecting member is arranged across one or more of the second piezoelectric structures, and the portion of the first connecting member opposite to one or more of the second piezoelectric structures protrudes in a direction away from the second piezoelectric structure and is connected to the first diaphragm assembly.

[0021] Optionally, the first connecting member includes a crossbeam, two transition portions and two connecting portions, the two transition portions are correspondingly connected to the two ends of the crossbeam, the two connecting portions are connected to the two transition portions one by one, the two connecting portions are correspondingly connected to the two first free ends, the angles between the transition portions and the crossbeam and the connecting portions are greater than 90 degrees, and the crossbeam is connected to the first diaphragm assembly.

[0022] Optionally, a plurality of the first piezoelectric structure and a plurality of the second piezoelectric structure are provided, and a plurality of the second piezoelectric structures are provided between two of the first piezoelectric structures spaced apart in the third direction;

[0023] The vibration assembly further includes a second connecting member, and a plurality of the second piezoelectric structures located between two of the first piezoelectric structures are connected to the same second connecting member, and the second connecting member is connected to the second diaphragm assembly.

[0024] Optionally, the width of the first piezoelectric structure gradually decreases along a direction from the first fixed end to the first free end; and / or the width of the second piezoelectric structure gradually decreases along a direction from the second fixed end to the second free end.

[0025] Optionally, at the same moment, the vibration direction of the first diaphragm assembly is opposite to the vibration direction of the second diaphragm assembly.

[0026] Beneficial effects of the present invention:

[0027] In the piezoelectric speaker provided by the present invention, the first diaphragm assembly and the second diaphragm assembly are arranged relative to each other in a first direction, and the vibration assembly includes a first piezoelectric structure and a second piezoelectric structure. The first piezoelectric structure for driving the first diaphragm assembly to vibrate and the second piezoelectric structure for driving the second diaphragm assembly to vibrate are arranged in the same layer, that is, the first piezoelectric structure and the second piezoelectric structure are on the same plane. On the basis of ensuring the driving effect, the space occupied by the vibration assembly in the first direction can be reduced, thereby making the size of the piezoelectric speaker in the first direction smaller, thereby making the piezoelectric speaker lighter and thinner. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0029] Figure 1 is a schematic structural diagram of a piezoelectric speaker provided by an embodiment of the present invention;

[0030] Figure 2 is a partial schematic diagram of a piezoelectric speaker provided by an embodiment of the present invention;

[0031] Figure 3 is a first exploded view of a piezoelectric speaker provided by an embodiment of the present invention;

[0032] Figure 4 is an exploded view of a first piezoelectric structure provided by an embodiment of the present invention;

[0033] Figure 5 is a top view of a piezoelectric speaker provided by an embodiment of the present invention without showing a first diaphragm assembly;

[0034] Figure 6 is a second exploded view of a piezoelectric speaker provided by an embodiment of the present invention;

[0035] Figure 7 is a first cross-sectional view of a piezoelectric speaker provided by an embodiment of the present invention;

[0036] Figure 8 is a second cross-sectional view of the piezoelectric speaker provided by the embodiment of the present invention;

[0037] Fig. 9 is a third exploded view of the piezoelectric speaker provided by an embodiment of the present invention;

[0038] Fig.10 FIG. 4 is a top view of a portion of a piezoelectric speaker provided by an embodiment of the present invention.

[0039] In the figure:

[0040] 100, support frame; 110, upper surface; 120, lower surface; 130, cavity; 140, upper frame; 150, lower frame;

[0041] 200, first diaphragm assembly; 210, first diaphragm; 220, first dome;

[0042] 300, second diaphragm assembly; 310, second diaphragm; 320, second dome;

[0043] 400, vibration component; 410, first piezoelectric structure; 411, first fixed end; 412, first free end; 413, first substrate; 414, first piezoelectric sheet; 420, second piezoelectric structure; 421, second fixed end; 422, second free end; 423, second substrate; 424, second piezoelectric sheet; 430, first connecting member; 431, crossbeam; 432, transition portion; 433, connecting portion; 440, second connecting member;

[0044] 500, circuit components;

[0045] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0046] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the present invention are further described below in conjunction with the accompanying drawings and through specific implementation methods. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the accompanying drawings, not all.

[0047] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0048] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly stipulated and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature. In the description of this embodiment, unless otherwise specified, "multiple" specifically refers to two or more.

[0050] In the description of this embodiment, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and other orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0051] It should be noted that when an element is referred to as being “fixed to” or “disposed on” another element, it may be directly on the other element or there may be a central element.

[0052] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0053] This embodiment provides a piezoelectric speaker that can be relatively thin and can be applied to electronic devices with high space requirements.

[0054] The speaker in this embodiment may be a MEMS (micro-electro-mechanical system) speaker. The MEMS speaker can be widely used in current mobile electronic devices due to its advantages such as low power consumption and light weight.

[0055] It should be noted that the electronic device may include a mobile phone, a tablet personal computer, a laptop, a personal digital assistant (PDA), a camera, a personal computer, a laptop, a vehicle-mounted device, a wearable device, augmented reality (AR) glasses, AR helmets, virtual reality (VR) glasses, VR helmets, fixed-line handsets (pickups), medical auxiliary equipment (such as hearing aids), various headphones (such as wireless headphones or wired headphones), and other devices with speakers. The embodiments of the present application do not impose any special restrictions on the specific forms of the above-mentioned electronic devices.

[0056] Before introducing this embodiment, in order to facilitate the following description, a three-dimensional coordinate system may be established in some drawings. Figure 1 The piezoelectric speaker shown is a rectangular example. Figure 2 As shown, the first direction X is the thickness direction of the piezoelectric speaker, the second direction Y is the length direction of the piezoelectric speaker, and the third direction Z is the width direction of the piezoelectric speaker, that is, any two of the first direction X, the second direction Y and the third direction Z are perpendicular to each other. It can be understood that the width direction of the piezoelectric speaker is smaller than the length direction of the speaker.

[0057] For example, Figures 1 to 3 As shown, the piezoelectric speaker includes a supporting frame 100 , a circuit assembly 500 , a first diaphragm assembly 200 , a second diaphragm assembly 300 and a vibration assembly 400 .

[0058] Exemplarily, the support frame 100 is made of a hard material, such as metal, plastic, etc., which is not limited in this embodiment. The support frame 100 is a frame structure, such as Figure 7 As shown, the two surfaces of the support frame 100 in the first direction X are an upper surface 110 and a lower surface 120. Figure 2 As shown, the support frame 100 forms a cavity 130 penetrating the upper surface 110 and the lower surface 120 to provide space for vibration of the vibration assembly 400 , the first diaphragm assembly 200 and the second diaphragm assembly 300 .

[0059] Optionally, the support frame 100 may be an independent component, or the support frame 100 may be a combined component. Figure 2 As shown, the support frame 100 includes an upper frame 140 and a lower frame 150 connected to each other, and the upper frame 140 and the lower frame 150 are arranged in a first direction X.

[0060] For example, Figure 3 or Figure 5As shown, the circuit assembly 500 is arranged on the support frame 100 and is used to be electrically connected to the vibration assembly 400, thereby providing acoustic and electrical signals to the vibration assembly 400. For example, the circuit assembly 500 can be clamped and fixed between the upper frame 140 and the lower frame 150. The circuit assembly 500 may include one or more circuit boards (not shown in the figure), which is not limited in this embodiment. A welding pad (not shown in the figure) is provided on the circuit board, and the vibration assembly 400 can be welded on the welding pad to achieve electrical connection between the circuit board and the vibration assembly 400.

[0061] In this embodiment, the first diaphragm assembly 200 is fixedly disposed on the support frame 100. Specifically, the periphery of the first diaphragm assembly 200 is fixedly connected to the support frame 100 and covers the cavity 130 of the support frame 100. The vibration assembly 400 can drive the first diaphragm assembly 200 to vibrate to achieve sound. Exemplarily, the periphery of the first diaphragm assembly 200 is fixedly connected to the upper frame 140; further, the periphery of the first diaphragm assembly 200 is fixedly connected to the surface of the upper frame 140 facing away from the lower frame 150.

[0062] The specific structure of the first diaphragm assembly 200 can refer to the prior art. In some optional embodiments, such as Figure 7 and Figure 8 As shown, the first diaphragm assembly 200 includes a first diaphragm 210 and a first dome 220. The periphery of the first diaphragm 210 is fixedly connected to the support frame 100, the first dome 220 is connected to the surface of the first diaphragm 210 facing the cavity 130, and the vibration assembly 400 is connected to the first dome 220 to drive the first diaphragm 210 to vibrate through the first dome 220 to produce sound.

[0063] The second diaphragm assembly 300 in this embodiment is fixedly disposed on the support frame 100, and is arranged opposite to the first diaphragm assembly 200 in the first direction X, forming a piezoelectric speaker with a dual diaphragm assembly. Specifically, the periphery of the second diaphragm assembly 300 is fixedly connected to the support frame 100, and covers the cavity 130 of the support frame 100. The vibration assembly 400 can drive the second diaphragm assembly 300 to vibrate to achieve sound. Exemplarily, the periphery of the second diaphragm assembly 300 is fixedly connected to the lower frame 150; further, the periphery of the second diaphragm assembly 300 is fixedly connected to the surface of the lower frame 150 facing away from the upper frame 140.

[0064] The specific structure of the second diaphragm assembly 300 can be found in the prior art. Figure 7 and Figure 8The second diaphragm assembly 300 includes a second diaphragm 310 and a second dome 320. The periphery of the second diaphragm 310 is fixedly connected to the support frame 100, the second dome 320 is connected to the surface of the second diaphragm 310 facing the cavity 130, and the vibration assembly 400 is connected to the second dome 320 to drive the second diaphragm 310 to vibrate through the second dome 320 to produce sound.

[0065] For example, Figure 2 As shown, the vibration assembly 400 in this embodiment is disposed in the cavity 130 and is located between the first diaphragm assembly 200 and the second diaphragm assembly 300 .

[0066] In some possible implementations, such as Figure 2 As shown, the vibration assembly 400 includes a first piezoelectric structure 410 and a second piezoelectric structure 420 disposed in the same layer on the support frame 100. The first piezoelectric structure 410 and the second piezoelectric structure 420 are both electrically connected to the circuit assembly 500, so that the circuit assembly 500 can provide acoustic and electrical signals to the first piezoelectric structure 410 and the second piezoelectric structure 420.

[0067] In this embodiment, the first piezoelectric structure 410 is connected to the first diaphragm assembly 200, and is used to drive the first diaphragm assembly 200 to vibrate along the first direction X, and the second piezoelectric structure 420 is connected to the second diaphragm assembly 300, and is used to drive the second diaphragm assembly 300 to vibrate along the first direction X, so that the two piezoelectric structures used to drive the two diaphragm assemblies are located in the same layer, thereby reducing the thickness of the vibration assembly 400, thereby reducing the thickness of the piezoelectric speaker, so that the space occupied by the piezoelectric speaker in the thickness direction is minimized, the piezoelectric speaker can be thinner, and thus the electronic device using the piezoelectric speaker is thinner. It should be noted that there is a gap between the first piezoelectric structure 410 and the second piezoelectric structure 420, that is, the first piezoelectric structure 410 and the second piezoelectric structure 420 do not contact each other, so that the two will not interfere with each other, ensuring the normal use of the piezoelectric speaker and preventing the generation of noise.

[0068] In the piezoelectric speaker provided in this embodiment, the first diaphragm assembly 200 and the second diaphragm assembly 300 are arranged relative to each other in the first direction X, and the vibration assembly 400 includes a first piezoelectric structure 410 and a second piezoelectric structure 420. The first piezoelectric structure 410 for driving the first diaphragm assembly 200 to vibrate and the second piezoelectric structure 420 for driving the second diaphragm assembly 300 to vibrate are arranged in the same layer, that is, the first piezoelectric structure 410 and the second piezoelectric structure 420 are in the same plane. On the basis of ensuring the driving effect, the space occupied by the vibration assembly 400 in the first direction X can be reduced, thereby making the size of the piezoelectric speaker in the first direction X smaller, so that the piezoelectric speaker can be lighter and thinner.

[0069] In some optional embodiments, such as Figure 4 As shown, the first piezoelectric structure 410 includes a first substrate 413 and a first piezoelectric sheet 414 disposed on at least one side of the first substrate 413 in the first direction X. In this embodiment, the first piezoelectric sheet 414 is disposed on both sides of the first substrate 413 in the first direction X. The material of the first substrate 413 can be plastic or metal, and the material of the first piezoelectric sheet 414 can be piezoelectric ceramic. After the first piezoelectric sheet 414 is energized, it will deform upward or downward in the first direction X according to the energized polarity, thereby driving the first substrate 413 to move in the first direction X. In addition, the first piezoelectric structure 410 has a first free end 412 and a first fixed end 411 that are opposite to each other in the second direction Y, and the first fixed end 411 is connected to one end of the support frame 100 and is electrically connected to the circuit component 500. Specifically, the first substrate 413 of the first fixed end 411 is connected to one end of the support frame 100, and the first piezoelectric sheet 414 of the first fixed end 411 is electrically connected to the circuit assembly 500, so that the circuit assembly 500 inputs an acoustic and electrical signal to the first piezoelectric sheet 414. The first free end 412 is disposed on a side of the first diaphragm assembly 200 facing the second diaphragm assembly 300, and is fixedly connected to the first diaphragm assembly 200. Specifically, the first substrate 413 of the first free end 412 is fixedly connected to the first diaphragm assembly 200, and is used to drive the first diaphragm assembly 200 to vibrate along the first direction X.

[0070] In the present embodiment, one end of the first piezoelectric structure 410 is fixedly connected to the support frame 100, and the other end is suspended in the cavity 130 to form a cantilever beam structure. After the first piezoelectric sheet 414 is energized, the first piezoelectric structure 410 in the cantilever beam structure will deform in the first direction X, causing the first substrate 413 at the first free end 412 to vibrate, thereby driving the first diaphragm assembly 200 to vibrate, causing the first diaphragm assembly 200 to push the air to make sound.

[0071] The specific structure of the second piezoelectric structure 420 is similar to the specific structure of the first piezoelectric structure 410. Specifically, Figure 6As shown, the second piezoelectric structure 420 includes a second substrate 423 and a second piezoelectric sheet 424 disposed on at least one side of the second substrate 423 in the first direction X. In this embodiment, the second substrate 423 is connected to the second piezoelectric sheet 424 on both sides in the first direction X. The material of the second substrate 423 can be plastic or metal, and the material of the second piezoelectric sheet 424 can be piezoelectric ceramic. After the second piezoelectric sheet 424 is energized, it will deform upward or downward in the first direction X according to the energized polarity, thereby driving the second substrate 423 to move in the first direction X. In addition, the second piezoelectric structure 420 has a second free end 422 and a second fixed end 421 that are opposite to each other in the second direction Y, and the second substrate 423 of the second fixed end 421 is connected to the other end of the support frame 100 and is electrically connected to the circuit component 500. Specifically, the second substrate 423 of the second fixed end 421 is connected to the other end of the support frame 100, and the second piezoelectric sheet 424 of the second fixed end 421 is electrically connected to the circuit assembly 500, so that the circuit assembly 500 inputs an acoustic and electrical signal to the first piezoelectric sheet 414. The second free end 422 is disposed on a side of the second diaphragm assembly 300 facing the first diaphragm assembly 200, and is fixedly connected to the second diaphragm assembly 300. Specifically, the second substrate 423 of the second free end 422 is fixedly connected to the second diaphragm assembly 300, and is used to drive the second diaphragm assembly 300 to vibrate along the first direction X.

[0072] In the present embodiment, one end of the second piezoelectric structure 420 is fixedly connected to the support frame 100, and the other end is suspended in the cavity 130 to form a cantilever beam structure. After the second piezoelectric sheet 424 is energized, the second piezoelectric structure 420 with a cantilever beam structure will deform in the first direction X, causing the second substrate 423 at the second free end 422 to vibrate, thereby driving the second diaphragm assembly 300 to vibrate, causing the second diaphragm assembly 300 to push the air to make sound.

[0073] In some optional embodiments, at the same time, the vibration direction of the first diaphragm assembly 200 is opposite to the vibration direction of the second diaphragm assembly 300, that is, at the same time, the first vibration assembly 400 and the second diaphragm assembly 300 move toward or away from each other, so that the movement directions of the two are opposite, thereby playing a shock-absorbing role, reducing the overall vibration amplitude of the piezoelectric speaker, thereby reducing the impact of the piezoelectric speaker on other components in the electronic device, and can also ensure the reliability of the electrical connection between the first piezoelectric sheet 414 of the first piezoelectric structure 410 and the second piezoelectric sheet 424 of the second piezoelectric structure 420 and the circuit assembly 500.

[0074] It is understandable that the vibration direction of the first diaphragm assembly 200 is the same as the vibration direction of the first piezoelectric structure 410, and the vibration direction of the second diaphragm assembly 300 is the same as the vibration direction of the second piezoelectric structure 420. For example, the circuit assembly 500 can input acoustic and electrical signals of equal magnitude and opposite polarity to the first piezoelectric sheet 414 and the second piezoelectric sheet 424, so that the deformation amplitudes of the first piezoelectric sheet 414 and the second piezoelectric sheet 424 are the same, but the deformation directions are opposite, thereby achieving the first piezoelectric structure 410 and the second piezoelectric structure 420 vibrating in opposite directions.

[0075] Since the first piezoelectric structure 410 usually maintains a state of extending along the second direction Y when not vibrating, and the first piezoelectric structure 410 and the first diaphragm assembly 200 have a certain distance in the first direction X, if the first substrate 413 of the first piezoelectric structure 410 is directly connected to the first diaphragm assembly 200, the first substrate 413 will be in a state of bending toward the first diaphragm assembly 200, and the first diaphragm assembly 200 will be pulled, which may easily cause damage to the first diaphragm assembly 200.

[0076] For this reason, Figure 3 As shown, the vibration assembly 400 in this embodiment also includes a first connector 430. The first connector 430 is connected between the first piezoelectric structure 410 and the first diaphragm assembly 200. For example, the first connector 430 is connected between the first substrate 413 of the first free end 412 and the first diaphragm assembly 200. By setting the first connector 430, when the first piezoelectric structure 410 is not vibrating, it can ensure that the first piezoelectric structure 410 remains in a state of extending along the second direction Y, and will not pull the first diaphragm assembly 200, thereby reducing the probability of damage to the first diaphragm assembly 200; and by setting the first connector 430, it can also ensure that the distance between the first piezoelectric structure 410 and the first diaphragm assembly 200 is a certain value, which is convenient for controlling the vibration of the first diaphragm assembly 200; in addition, when the connection area of ​​the first free end 412 is small, by setting the first connector 430, the connection area between the first connector 430 and the first diaphragm assembly 200 can be increased, thereby improving the connection stability and reliability.

[0077] Similarly, in order to reduce the probability of damage to the first diaphragm assembly 200, as Figure 3As shown, the vibration assembly 400 also includes a second connecting member 440, and the second connecting member 440 is connected between the second piezoelectric structure 420 and the second diaphragm assembly 300. For example, the second connecting member 440 is connected between the second free end 422 and the second diaphragm assembly 300. By setting the second connecting member 440, when the second piezoelectric structure 420 is not vibrating, it can ensure that the second piezoelectric structure 420 remains in a state of extending along the second direction Y, and will not pull the second diaphragm assembly 300, thereby reducing the probability of damage to the second diaphragm assembly 300; and by setting the second connecting member 440, it can also ensure that the distance between the second piezoelectric structure 420 and the second diaphragm assembly 300 is a certain value, which is convenient for controlling the vibration of the second diaphragm assembly 300; in addition, when the connection area of ​​the second free end 422 is small, by setting the second connecting member 440, the connection area between the second connecting member 440 and the second diaphragm assembly 300 can be increased, thereby improving the connection stability and reliability.

[0078] The number of the first piezoelectric structures 410 can be selected according to actual needs. The first piezoelectric structure 410 can be provided with one or more. When there is one first piezoelectric structure 410, there is one first connector 430. When there are multiple first piezoelectric structures 410, the number of the first connector 430 can be multiple.

[0079] In some optional embodiments, when there are multiple first piezoelectric structures 410, only one first connecting member 430 is provided, and all first piezoelectric structures 410 are connected to the one first connecting member 430, so as to be connected to the first diaphragm assembly 200 through the first connecting member 430. In this way, the number of first connecting members 430 can be reduced, and the consistency of movement of the first diaphragm assembly 200 can be ensured, thereby reducing the number of components of the piezoelectric speaker and facilitating assembly.

[0080] In some other optional embodiments, when there are multiple first piezoelectric structures 410, there are multiple first connectors 430, and each first connector 430 is connected to at least one first piezoelectric structure 410. For example, multiple first connectors 430 correspond to multiple first piezoelectric structures 410 one by one, and each first piezoelectric structure 410 is connected to the corresponding first connector 430, so that each first piezoelectric structure 410 can be connected to the first diaphragm assembly 200 through the first connector 430. Alternatively, there are multiple first connectors 430, and each first connector 430 is connected to at least two first piezoelectric structures 410, that is, at least two first piezoelectric structures 410 share one first connector 430, which can reduce the number of first connectors 430 used.

[0081] Similarly, the number of the second piezoelectric structures 420 can be selected according to actual needs. The second piezoelectric structure 420 can be provided with one or more. When the second piezoelectric structure 420 is provided with one, the second connecting member 440 is provided with one. When the second piezoelectric structure 420 is provided with multiple, the number of the second connecting members 440 can be multiple.

[0082] In some optional embodiments, when there are multiple second piezoelectric structures 420, only one second connecting member 440 is provided, and all second piezoelectric structures 420 are connected to the one second connecting member 440, so as to be connected to the second diaphragm assembly 300 through the second connecting member 440. In this way, the number of second connecting members 440 can be reduced, and the consistency of the movement of the second diaphragm assembly 300 can be ensured, thereby reducing the number of components of the piezoelectric speaker and facilitating assembly.

[0083] In some other optional embodiments, when there are multiple second piezoelectric structures 420, there are multiple second connecting members 440, and each second connecting member 440 is connected to at least one second piezoelectric structure 420. For example, multiple second connecting members 440 correspond to multiple second piezoelectric structures 420 one by one, and each second piezoelectric structure 420 is connected to the corresponding second connecting member 440, so that each second piezoelectric structure 420 can be connected to the second diaphragm assembly 300 through the second connecting member 440. Alternatively, when there are multiple second piezoelectric structures 420, there are multiple second connecting members 440, and each second connecting member 440 is connected to at least two second piezoelectric structures 420, that is, at least two second piezoelectric structures 420 share one second connecting member 440, which can reduce the number of second connecting members 440 used.

[0084] In order to improve the low-frequency sensitivity of the loudspeaker, for example, Figure 5As shown, the orthographic projections of the first piezoelectric structure 410 and the second piezoelectric structure 420 in the third direction Z at least partially overlap, that is, the orthographic projections of the first piezoelectric structure 410 and the second piezoelectric structure 420 in the third direction Z have overlapping parts, that is, the first piezoelectric structure 410 and the second piezoelectric structure 420 can be staggered with each other, so that the lengths of the first piezoelectric structure 410 and the second piezoelectric structure 420 can be longer, so as to increase the areas of the first piezoelectric structure 410 and the second piezoelectric structure 420, and further improve the sensitivity of the piezoelectric speaker. In addition, the lengths of the first piezoelectric structure 410 and the second piezoelectric structure 420 are longer, so that the force applied by the first piezoelectric structure 410 on the first diaphragm assembly 200 can be closer to the vertical first diaphragm assembly 200, and the force applied by the second piezoelectric structure 420 on the second diaphragm assembly 300 can be closer to the vertical second diaphragm assembly 300, thereby improving the driving effect of the first diaphragm assembly 200 and the second diaphragm assembly 300. In addition, the long lengths of the first piezoelectric structure 410 and the second piezoelectric structure 420 will also reduce the resonance frequency, thereby increasing the low-frequency sensitivity of the piezoelectric speaker.

[0085] Optionally, the area of ​​the overlapping portion of the orthographic projections of the first piezoelectric structure 410 and the second piezoelectric structure 420 in the third direction Z is smaller than the area of ​​the orthographic projection of the first piezoelectric structure 410 in the third direction Z, and smaller than the area of ​​the orthographic projection of the second piezoelectric structure 420 in the third direction Z.

[0086] In some optional embodiments, when there are multiple first piezoelectric structures 410 and multiple second piezoelectric structures 420, the first free ends 412 of the multiple first piezoelectric structures 410 and the second free ends 422 of the multiple second piezoelectric structures 420 are alternately arranged in the third direction Z, so that the first piezoelectric structure 410 will not affect the extension of the second piezoelectric structure 420 in the second direction Y, and the second piezoelectric structure 420 will not affect the extension of the first piezoelectric structure 410 in the second direction Y, so that the lengths of the first piezoelectric structure 410 and the second piezoelectric structure 420 in the first direction X can be longer, thereby reducing the resonance frequency and improving the low-frequency sensitivity. Furthermore, the alternating arrangement of the first piezoelectric structure 410 and the second piezoelectric structure 420 can also improve the uniformity of the connection position between the first piezoelectric structure 410 and the first diaphragm assembly 200 in the third direction Z, and improve the uniformity of the connection position between the second piezoelectric structure 420 and the second diaphragm assembly 300 in the third direction Z, thereby reducing the probability of damage to the first diaphragm assembly 200 and the second diaphragm assembly 300 due to excessive local force, and improving the stability of driving the first diaphragm assembly 200 and the second diaphragm assembly 300.

[0087] In some other optional embodiments, when the first piezoelectric structure 410 and the second piezoelectric structure 420 are provided in plurality, the plurality of first piezoelectric structures 410 and the plurality of second piezoelectric structures 420 may not be arranged alternately. For example, Fig. 9 and Fig.10 As shown, there are multiple second piezoelectric structures 420 between two first piezoelectric structures 410 spaced apart in the third direction Z. It is understandable that multiple first piezoelectric structures 410 may also be provided between two second piezoelectric structures 420 spaced apart in the third direction Z, and this embodiment is not limited thereto.

[0088] Further, when there are a plurality of second piezoelectric structures 420 between two first piezoelectric structures 410 spaced apart in the third direction Z, the plurality of second piezoelectric structures 420 between the two first piezoelectric structures 410 are connected to the same second connecting member 440 .

[0089] In this embodiment, Figure 5 and Figure 6 As shown, there are multiple first piezoelectric structures 410 arranged along the third direction Z, and at least one second piezoelectric structure 420 is provided. Two adjacent first piezoelectric structures 410 in the third direction Z and one or more second piezoelectric structures 420 form a piezoelectric group (not shown in the figure). The vibration assembly 400 includes at least one piezoelectric group. When the vibration assembly 400 includes multiple piezoelectric groups, the multiple piezoelectric groups are arranged in sequence in the third direction Z. In one piezoelectric group, the second free ends 422 of one or more second piezoelectric structures 420 are located between the two first piezoelectric structures 410 in the third direction Z to make full use of the space of the piezoelectric speaker in the third direction Z. It should be noted that when there are multiple piezoelectric groups, two adjacent piezoelectric groups in the third direction Z can be independent of each other, that is, the first piezoelectric structure 410 in one piezoelectric group will not be reused in another piezoelectric group. Alternatively, two adjacent piezoelectric groups in the third direction Z may also share a first piezoelectric structure 410 , that is, the first piezoelectric structure 410 in one piezoelectric group may also serve as the first piezoelectric structure 410 in another piezoelectric group, which is not limited in this embodiment.

[0090] In this embodiment, Figure 5 and Figure 6 As shown, two first piezoelectric structures 410 are provided, and one second piezoelectric structure 420 is provided. The second free end 422 of the second piezoelectric structure 420 is located between the two first piezoelectric structures 410 in the third direction Z. In this way, the number of the first piezoelectric structure 410 and the second piezoelectric structure 420 will not be too large, and the number of components of the piezoelectric speaker can be reduced on the basis of achieving the driving of the two diaphragm assemblies.

[0091] For further information, please see Figure 5 and Figure 6 In a piezoelectric group, two first piezoelectric structures 410 are connected to the same first connecting member 430, and the first connecting member 430 is arranged across one or more second piezoelectric structures 420 in the piezoelectric group. The portion of the first connecting member 430 opposite to the one or more second piezoelectric structures 420 protrudes in a direction away from the one or more second piezoelectric structures 420 and is connected to the first diaphragm assembly 200 to achieve the connection between the two first piezoelectric structures 410 and the first diaphragm assembly 200. By raising the portion of the first connecting member 430 that is opposite to the one or more second piezoelectric structures 420 in a direction away from the one or more second piezoelectric structures 420, on the one hand, it facilitates connection with the first diaphragm assembly 200, and on the other hand, it can reserve vibration space for one or more second piezoelectric structures 420, so that the first connecting member 430 will not interfere with the vibration of the second piezoelectric structure 420, and the second piezoelectric structure 420 will not collide with the first connecting member 430 when vibrating, thereby preventing the piezoelectric speaker from generating noise and ensuring the accuracy of the second piezoelectric structure 420 driving the second diaphragm assembly 300.

[0092] For example, Figure 6 or Figure 8 As shown, the first connecting member 430 includes a beam 431, two transition parts 432 and two connecting parts 433. Among them, the length direction of the beam 431 is the third direction Z, the two transition parts 432 are connected to the two ends of the length direction of the beam 431, and the two connecting parts 433 correspond to the two transition parts 432 one by one, and each connecting part 433 is connected to one end of the transition part 432 away from the beam 431 to form a "J"-shaped first connecting member 430. The two connecting parts 433 are connected to the two first free ends 412 in the corresponding piezoelectric group one by one. In this way, the first connecting member 430 can be better supported between the first diaphragm assembly 200 and the two first piezoelectric structures 410, and the first connecting member 430 can have a higher structural domain strength, reducing the probability of deformation of the first connecting member 430. It should be noted that the large surface of the beam 431 (i.e., the surface with a larger area of ​​the beam 431) is connected to the first diaphragm assembly 200 to increase the connection area between the two and ensure the connection strength. Similarly, the large surface of the connecting portion 433 (ie, the surface of the connecting portion 433 with a larger area) is connected to the first piezoelectric structure 410 to improve the connection strength between the connecting portion 433 and the first piezoelectric structure 410 and reduce the probability of connection failure.

[0093] Further optionally, if Figure 8As shown, the angle between the transition part 432 and the crossbeam 431 is a, and the angle between the transition part 432 and the connecting part 433 is b, wherein a and b are both greater than 90 degrees. Thus, on the one hand, the first connecting member 430 has a certain elasticity in the first direction X, thereby being able to buffer the force transmitted from the first piezoelectric structure 410 to the first diaphragm assembly 200, thereby reducing the probability of damage to the first diaphragm assembly 200; on the other hand, the distance between the two transition parts 432 and one end of the corresponding connecting part 433 is relatively large, thereby being able to meet the requirement that the transition part 432 does not interfere with the second piezoelectric structure 420.

[0094] like Figure 2 As shown, the second connecting member 440 in this embodiment can be a block-shaped structure, which is not limited in this embodiment.

[0095] In order to make the areas of the first piezoelectric structure 410 and the second piezoelectric structure 420 larger, in this embodiment, Figure 5 As shown, along the direction from the first fixed end 411 to the first free end 412, the width of the first piezoelectric structure 410 gradually decreases; along the direction from the second fixed end 421 to the second free end 422, the width of the second piezoelectric structure 420 gradually decreases. In some optional embodiments, the first piezoelectric structure 410 and the second piezoelectric structure 420 have the same shape, and the number of the first piezoelectric structure 410 is the same as the number of the second piezoelectric structure 420, so as to ensure the consistency of driving the first diaphragm assembly 200 and the second diaphragm assembly 300. Preferably, the number of the first piezoelectric structure 410 and the number of the second piezoelectric structure 420 are both even numbers.

[0096] For example, the first piezoelectric structure 410 and the second piezoelectric structure 420 may both be in the shape of a trapezoid. Of course, it is understandable that the first piezoelectric structure 410 and the second piezoelectric structure 420 may also be in the shape of a rectangle, a triangle, etc., which is not limited in this embodiment.

[0097] In the piezoelectric speaker provided in this embodiment, the first piezoelectric structure 410 and the second piezoelectric structure 420 are in the same layer, and the first piezoelectric structure 410 is connected to the first diaphragm assembly 200, and the second piezoelectric structure 420 is connected to the second diaphragm assembly 300, and drives the first diaphragm assembly 200 and the second diaphragm assembly 300 to vibrate in opposite directions, thereby achieving the thinnest piezoelectric speaker on the basis of a dual diaphragm structure, reducing the space occupied by the piezoelectric speaker in the first direction X, and also having a shock-absorbing effect.

[0098] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A piezoelectric speaker, characterized in that include: A support frame (100), wherein the support frame (100) forms a cavity (130) penetrating the upper surface (110) and the lower surface (120); A circuit assembly (500) is arranged on the supporting frame (100); A first diaphragm assembly (200), wherein the periphery of the first diaphragm assembly (200) is fixedly connected to the support frame (100); A second diaphragm assembly (300) is arranged opposite to the first diaphragm assembly (200) in a first direction (X), and the periphery of the second diaphragm assembly (300) is fixedly connected to the support frame (100); A vibration component (400) is arranged in the cavity (130) and is located between the first diaphragm component (200) and the second diaphragm component (300), and the vibration component (400) includes a first piezoelectric structure (410) and a second piezoelectric structure (420) which are arranged in the same layer on the support frame (100); the first piezoelectric structure (410) and the second piezoelectric structure (420) are both electrically connected to the circuit component (500); the first piezoelectric structure (410) is fixedly connected to the first diaphragm component (200) and is used to drive the first diaphragm component (200) to vibrate along the first direction (X); the second piezoelectric structure (420) is fixedly connected to the second diaphragm component (300) and is used to drive the second diaphragm component (300) to vibrate along the first direction (X).

2. The piezoelectric speaker according to claim 1, wherein: The vibration assembly (400) further comprises a first connecting member (430), wherein the first connecting member (430) is connected between the first piezoelectric structure (410) and the first diaphragm assembly (200); and / or, The vibration component (400) further comprises a second connecting member (440), wherein the second connecting member (440) is connected between the second piezoelectric structure (420) and the second diaphragm component (300).

3. The piezoelectric speaker according to claim 1, wherein: There are multiple first piezoelectric structures (410), and the vibration assembly (400) further includes a first connecting member (430), and the first connecting member (430) is connected to the first diaphragm assembly (200); there is one first connecting member (430), and all the first piezoelectric structures (410) are connected to the first connecting member (430) to be connected to the first diaphragm assembly (200) through the first connecting member (430); or there are multiple first connecting members (430), and each first connecting member (430) is connected to at least one first piezoelectric structure (410).

4. The piezoelectric speaker according to claim 3, characterized in that There are multiple second piezoelectric structures (420), and the vibration assembly (400) also includes a second connecting member (440), and the second connecting member (440) is connected to the second diaphragm assembly (300); there is one second connecting member (440), and all the second piezoelectric structures (420) are connected to the second connecting member (440) to be connected to the second diaphragm assembly (300) through the second connecting member (440); or, there are multiple second connecting members (440), and each second connecting member (440) is connected to at least one second piezoelectric structure (420).

5. The piezoelectric speaker according to claim 1, wherein: The first piezoelectric structure (410) has a first free end (412) and a first fixed end (411) which are opposite to each other in a second direction (Y), the first fixed end (411) is connected to one end of the support frame (100), and the first free end (412) is fixedly connected to the first diaphragm assembly (200); the second piezoelectric structure (420) has a second free end (422) and a second fixed end (421) which are opposite to each other in the second direction (Y), the second fixed end (421) is connected to the other end of the support frame (100), and the second free end (422) is fixedly connected to the second diaphragm assembly (300); wherein the first direction (X) is perpendicular to the second direction (Y).

6. The piezoelectric speaker according to claim 5, characterized in that The orthographic projections of the first piezoelectric structure (410) and the second piezoelectric structure (420) in a third direction (Z) at least partially overlap; wherein the third direction (Z) is perpendicular to both the first direction (X) and the second direction (Y).

7. The piezoelectric speaker according to claim 6, wherein: A plurality of the first piezoelectric structures (410) are arranged along the third direction (Z), and at least one second piezoelectric structure (420) is provided. Two adjacent first piezoelectric structures (410) and one or more second piezoelectric structures (420) in the third direction (Z) form a piezoelectric group. In one of the piezoelectric groups, the second free ends (422) of one or more second piezoelectric structures (420) are located between the two first piezoelectric structures (410) in the third direction (Z).

8. The piezoelectric speaker according to claim 7, wherein: The vibration assembly (400) further includes a first connecting member (430); in one of the piezoelectric groups, two of the first piezoelectric structures (410) are connected to the same first connecting member (430), the first connecting member (430) is arranged across one or more of the second piezoelectric structures (420), and the portion of the first connecting member (430) opposite to the one or more of the second piezoelectric structures (420) protrudes in a direction away from the second piezoelectric structure (420), and is connected to the first diaphragm assembly (200).

9. The piezoelectric speaker according to claim 8, characterized in that The first connecting member (430) includes a crossbeam (431), two transition parts (432) and two connecting parts (433), the two transition parts (432) are correspondingly connected to the two ends of the crossbeam (431), the two connecting parts (433) are connected to the two transition parts (432) one by one, the two connecting parts (433) are correspondingly connected to the two first free ends (412), the angles between the transition part (432) and the crossbeam (431) and the connecting parts (433) are all greater than 90 degrees, and the crossbeam (431) is connected to the first diaphragm assembly (200).

10. The piezoelectric speaker according to claim 6, wherein: A plurality of the first piezoelectric structures (410) and a plurality of the second piezoelectric structures (420) are provided, and a plurality of the second piezoelectric structures (420) are provided between two of the first piezoelectric structures (410) spaced apart in the third direction (Z); The vibration assembly (400) further comprises a second connecting member (440), a plurality of the second piezoelectric structures (420) located between two of the first piezoelectric structures (410) are connected to the same second connecting member (440), and the second connecting member (440) is connected to the second diaphragm assembly (300).

11. The piezoelectric speaker according to claim 5, wherein: The width of the first piezoelectric structure (410) gradually decreases along the direction from the first fixed end (411) to the first free end (412); and / or the width of the second piezoelectric structure (420) gradually decreases along the direction from the second fixed end (421) to the second free end (422).

12. The piezoelectric speaker according to any one of claims 1 to 11, characterized in that: At the same time, the vibration direction of the first diaphragm assembly (200) is opposite to the vibration direction of the second diaphragm assembly (300).

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