Sound production monomer and electronic device

Abstract

This invention discloses a sound-generating unit and electronic device, relating to the field of electroacoustic conversion technology. The vibration unit includes a diaphragm, a housing, and a temperature control unit. The diaphragm comprises a flexible substrate, a shape memory alloy driving element, and a composite layer stacked sequentially. The vibration unit is positioned at the mounting opening of the housing. The heating module of the temperature control unit includes a power amplifier and a signal modulation module electrically connected. An audio signal, modulated by the signal modulation module, is amplified by the power amplifier to heat the shape memory alloy driving element, causing it to deform and drive the vibration unit to vibrate from an initial state to a preset state. The heat dissipation module of the temperature control unit dissipates heat from the shape memory alloy driving element when the vibration unit is in the preset state, cooling the element and driving the vibration unit to return to its initial state. This invention offers advantages such as increased response frequency, reduced distortion, improved heating and cooling efficiency, and high-fidelity audio reproduction.

Description

Technical Field

[0001] This invention relates to the field of electroacoustic conversion technology, and in particular to a sound-generating unit and electronic device. Background Technology

[0002] Traditional speaker drivers, such as dynamic loudspeakers, primarily operate on the principle of electromagnetic induction. A dynamic loudspeaker consists of a magnet, voice coil, and diaphragm, relying on the voice coil's movement within the magnetic field generated by the magnet to drive the diaphragm and produce sound. However, dynamic loudspeakers suffer from drawbacks such as large size, high structural rigidity, fixed form, and difficulty in integration. With the rapid development of wearable devices, flexible displays, and the Internet of Things (IoT), there is an urgent need for thinner, more flexible, and even stretchable speaker drivers.

[0003] Shape memory alloys have the property of undergoing reversible phase transitions when the temperature changes, resulting in large deformation and huge driving force. Therefore, there are ideas to use the temperature changes of shape memory alloys to drive the diaphragm to produce sound. Although this idea overcomes the defects of moving coil loudspeakers, it still has problems such as low response frequency, severe distortion, poor cooling efficiency and inability to achieve high-fidelity audio reproduction. Summary of the Invention

[0004] The main objective of this invention is to propose a sound-generating unit and electronic device, which aims to solve the technical problems of existing sound-generating units that use the temperature change of shape memory alloy materials to drive the diaphragm to produce sound, such as low response frequency, severe distortion, poor cooling efficiency, and inability to achieve high-fidelity audio reproduction.

[0005] To achieve the above objectives, the present invention proposes a sound-generating unit, the sound-generating unit comprising:

[0006] A vibration unit, the vibration unit including a diaphragm, the diaphragm including a flexible substrate, a shape memory alloy driving component and a composite layer stacked in sequence; The housing has a mounting cavity formed inside it, and a mounting opening is formed on one side of the mounting cavity. The vibration unit is disposed at the mounting opening, and the flexible substrate is mounted on the housing with its two edges along the extension direction of the vibration unit. A temperature control unit, comprising a heating module and a heat dissipation module, both mounted on the housing, wherein the heating module comprises an electrically connected power amplifier and a signal modulation module, and the power amplifier is electrically connected to the shape memory alloy driver; After the audio signal is modulated by the signal modulation module, it is amplified by a power amplifier to heat the shape memory alloy driver, causing it to deform and drive the vibration unit to vibrate from the initial state to the preset state. The heat dissipation module is used to dissipate heat from the shape memory alloy driver when the vibration unit is in the preset state, so that the shape memory alloy driver cools down and drives the vibration unit to return from the preset state to the initial state. The vibration unit drives the air to produce sound during the reciprocating vibration between the initial state and the preset state.

[0007] In one embodiment, when the vibration unit is in the initial state, the shape memory alloy drive component is a bent structure, and the bent structure has multiple sequentially arranged bends along the extension direction of the vibration unit; The memory alloy drive is configured to deform and gradually tighten during heating to eliminate all the bends, and to form a smooth arc-shaped structure that bulges away from the housing when the vibration unit is in the preset state. The memory alloy drive is also configured to deform during heat dissipation and gradually relax to reform all the said bends, and to reset from the smooth arc structure to the bent structure when the vibration unit is in the initial state. The shape of the vibration unit always changes in accordance with the shape of the shape memory alloy drive component.

[0008] In one embodiment, the bent structure alternately forms multiple peaks and multiple troughs along the extension direction of the vibration unit, and each of the peaks and troughs is a bend. The memory alloy drive is configured to deform and gradually tighten during heating, so that each of the crests and troughs can be flattened to eliminate all the bends, and to form the smooth arc structure when the vibration unit is in the preset state. The shape memory alloy drive is also configured to deform and gradually relax during heat dissipation to reform a plurality of wave peaks and a plurality of wave troughs that are alternately distributed along the extension direction of the vibration unit, and to reset from the smooth arc structure to the bent structure when the vibration unit is in the initial state.

[0009] In one embodiment, when the vibration unit is in the initial state, the shape memory alloy drive is a first bent structure, and the first bent structure has a plurality of sequentially arranged first bends along the extension direction of the vibration unit. The shape memory alloy drive is configured to deform during heating so that all the first bends are bent in the opposite direction, so that the shape of each first bend is transformed into the shape of a second bend, and a second bend structure is formed when the vibration unit is in the preset state. The second bend structure has a plurality of second bends arranged sequentially along the extension direction of the vibration unit, and each second bend is formed by bending the corresponding first bend in the opposite direction. The memory alloy drive is also configured to deform during heat dissipation to cause all the second bends to bend in the opposite direction, so that the shape of each second bend changes to the shape of the first bend, and resets from the second bend structure to the first bend structure when the vibration unit is in the initial state. The shape of the vibration unit always changes in accordance with the shape of the shape memory alloy drive component.

[0010] In one embodiment, the first bent structure alternately forms a plurality of first peaks and a plurality of first troughs along the extension direction of the vibration unit, and each first peak and each first trough is a first bend. The shape memory alloy drive is configured to deform during heating so that all the first peaks and all the first troughs bend in the opposite direction, so that the shape of each first peak and each first trough is transformed into the shape of the second trough and the second peak respectively, and the second bent structure is formed when the vibration unit is in the preset state. The shape memory alloy drive is also configured to deform during heat dissipation, causing all the second peaks and all the second troughs to bend in opposite directions, so that the shapes of each second peak and each second trough correspond to the shapes of the first trough and the first peak, respectively, and to reset from the second bent structure to the first bent structure when the vibration unit is in the initial state.

[0011] In one embodiment, the shape memory alloy driving element is a shape memory alloy wire or a shape memory alloy film, and the shape memory alloy wire or the shape memory alloy film is laid on the surface of the flexible substrate facing the composite layer along the extension direction of the flexible substrate; And / or, the shape memory alloy driver is electrically connected to the power amplifier via two electrodes.

[0012] In one embodiment, when the vibration unit is in the initial state, the shape memory alloy drive is cooled to Ta, where Ta = Ms - T1, and Ms is the martensite initiation temperature, and T1 is at least 10°C. When the vibration unit is in the preset state, the shape memory alloy drive component is heated to Tb, where Tb = Af + T2, Af is the austenite termination temperature, Af is greater than Ms, and T2 is at least 10°C.

[0013] In one embodiment, the heat dissipation module includes a cooling pump, a microfluidic pipe, and a heat dissipation component. The outlet of the cooling pump is connected to the inlet of the microfluidic pipe, the outlet of the microfluidic pipe is connected to the inlet of the cooling pump, and the heat dissipation component is provided on the path connecting the outlet of the microfluidic pipe and the inlet of the cooling pump, so that the cooling pump, the microfluidic pipe, and the heat dissipation component form a circulating heat dissipation system. The cooling pump is installed in the housing and is used to pump coolant into the microfluidic channel. The microfluidic channel is disposed on the flexible substrate corresponding to the shape memory alloy driving component, so as to absorb the heat of the shape memory alloy driving component through the coolant flowing inside it and dissipate heat from the shape memory alloy driving component. The heat dissipation component is disposed on the outer peripheral edge of the housing or the flexible substrate and is used to dissipate heat from the coolant.

[0014] In one embodiment, the microfluidic channel is disposed on the surface of the flexible substrate facing the shape memory alloy driver and is matched with the extension path of the shape memory alloy driver. The shape memory alloy driver is attached to or passes through the outer wall of the microfluidic channel, and a thermally conductive insulating component is also disposed between the shape memory alloy driver and the microfluidic channel. And / or, the heat sink is at least one of a semiconductor cooler, a micro fan, or a heat sink fin.

[0015] In one embodiment, the vibration unit further includes folded rings, with two folded rings connected to each end of the diaphragm, and the end of each folded ring away from the diaphragm is mounted on the housing via a support member; And / or, the flexible substrate is a polyimide film or thermally conductive rubber; And / or, the memory alloy drive is a nitinol memory alloy wire or a nitinol memory alloy film; And / or, the composite layer includes a porous structure layer and a sealing film, wherein the porous structure layer is stacked on the shape memory alloy drive component, and the sealing film is composited on the surface of the porous structure layer opposite to the shape memory alloy drive component; the porous structure layer is a carbon fiber woven mesh or a porous metal foam.

[0016] The present invention also proposes an electronic device that uses the sound-generating unit as described above.

[0017] In this invention, a sound-generating unit incorporates a shape memory alloy (MMA) driver within a diaphragm and a heating module. The audio signal, modulated by PWM or PAM modulation using a signal modulation module, is then amplified by a power amplifier to heat the MMA driver, causing it to rapidly heat up and deform. This heats the MMA driver, driving the vibration unit to vibrate rapidly from an initial state to a preset state. When the vibration unit is in the preset state, the heating module stops heating the MMA driver, and a heat dissipation module cools it down, restoring the MMA driver to its pre-heating shape. This again drives the vibration unit to rapidly return to its initial state. When the vibration unit returns to its initial state, the heat dissipation module can pause cooling the MMA driver. The heating module then resumes heating the MMA driver, causing it to heat up and deform again, driving the vibration unit to vibrate rapidly from the initial state to the preset state once more. This cycle repeats, enabling the vibration unit to vibrate back and forth between the initial and preset states to drive airflow and produce sound.

[0018] This invention utilizes a heating module and a heat dissipation module within a temperature control unit to heat and dissipate heat from a shape memory alloy (MMA) driver component, respectively. This improves the heating and cooling efficiency of the MMA driver, enabling it to deform rapidly. This, in turn, drives the vibration unit to vibrate rapidly between its initial and preset states. This not only increases the response frequency but also overcomes the thermal inertia bottleneck of the MMA driver, extending the effective frequency range of the vibration unit to a wider mid-frequency band and significantly reducing distortion. Furthermore, the signal modulation module of the heating module can be optimized based on the characteristics of the MMA driver. Nonlinear compensation of the MMA driver significantly improves the frequency response accuracy and acoustic performance of the speaker. By optimizing the characteristics of the MMA driver, the phase transition process can be precisely controlled, making the vibration of the vibration unit more linear, effectively reducing harmonic and phase distortion, and improving sound clarity and fidelity. Simultaneously, this compensation control also enhances the dynamic response capability of the speaker, resulting in richer sound details, faster transient response, and better overall sound quality, achieving high-fidelity audio reproduction. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1This is a schematic diagram of the assembly of a sound-generating unit according to an embodiment of the present invention; Figure 2 This is a schematic side view of the diaphragm in a sound-generating unit according to an embodiment of the present invention; Figure 3 This is a schematic diagram showing the deformation of the shape memory alloy driving component in the sound-generating unit according to the first embodiment of the present invention; wherein, the dotted line represents the vibration unit in the initial state, and the solid line represents the vibration unit in the preset state; Figure 4 This is a schematic diagram of another side view of the diaphragm in a sound-generating unit according to an embodiment of the present invention; Figure 5 This is another three-dimensional schematic diagram of the diaphragm in a sound-generating unit according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the deformation of the shape memory alloy driving component in the sound-generating unit according to the second embodiment of the present invention; wherein, the dotted line indicates that the vibration unit is in the initial state, and the solid line indicates that the vibration unit is in the preset state.

[0021] Explanation of icon numbers: 100. Sound-generating unit; 10. Vibration unit; 11. Diaphragm; 111. Flexible substrate; 112. Shape memory alloy drive component; 112a. Bending structure; 1121. Wave bend; 1122. Wave crest; 1123. Wave trough; 112b. Smooth arc structure; 112c. First bending structure; 1124. First wave bend; 1125. First wave crest; 1126. First wave trough; 112d. Second bending structure; 1127. Second wave bend; 1128. Second wave crest; 1129. Second wave trough; 113. Composite layer; 114. Electrode; 12. Folded ring; 13. Support component; 20. Temperature control unit; 21. Heating module; 22. Heat dissipation module; 221. Cooling pump; 222. Microfluidic channel; 223. Heat dissipation component; 30. Housing.

[0022] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0025] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0026] Traditional speaker drivers, such as dynamic loudspeakers, primarily operate on the principle of electromagnetic induction. A dynamic loudspeaker consists of a magnet, voice coil, and diaphragm, relying on the voice coil's movement within the magnetic field generated by the magnet to drive the diaphragm and produce sound. However, dynamic loudspeakers suffer from drawbacks such as large size, high structural rigidity, fixed form, and difficulty in integration. With the rapid development of wearable devices, flexible displays, and the Internet of Things (IoT), there is an urgent need for thinner, more flexible, and even stretchable speaker drivers.

[0027] Shape memory alloys have the property of undergoing reversible phase transitions when the temperature changes, resulting in large deformation and huge driving force. Therefore, there are ideas to use the temperature changes of shape memory alloys to drive the diaphragm to produce sound. Although this idea overcomes the defects of moving coil loudspeakers, it still has problems such as low response frequency, severe distortion, poor cooling efficiency and inability to achieve high-fidelity audio reproduction.

[0028] To address the above problems, this invention proposes a sound-generating unit and an electronic device.

[0029] In one embodiment, the sound-generating unit 100 includes a vibration unit 10, a housing 30, and a temperature control unit 20. The vibration unit 10 includes a diaphragm 11, which comprises a flexible substrate 111, a shape memory alloy driving element 112, and a composite layer 113 stacked sequentially. A mounting cavity is formed within the housing 30, and a mounting opening is formed on one side of the mounting cavity. The vibration unit 10 is disposed at the mounting opening, and the two edges of the flexible substrate 111 along the extending direction of the vibration unit 10 are mounted on the housing 30. The temperature control unit 20 includes a heating module 21 and a heat dissipation module 22, both mounted on the housing 30. The heating module 21 includes an electrical connection... The system includes a power amplifier and a signal modulation module. The power amplifier is electrically connected to the shape memory alloy driver 112. After the audio signal is modulated by the signal modulation module, it is applied to the shape memory alloy driver 112 by the power amplifier to heat the shape memory alloy driver 112, causing it to heat up and deform, thereby driving the vibration unit 10 to vibrate from the initial state to the preset state. The heat dissipation module 22 is used to dissipate heat from the shape memory alloy driver 112 when the vibration unit 10 is in the preset state, so that the shape memory alloy driver 112 cools down, thereby driving the vibration unit 10 to return to the initial state from the preset state. During the reciprocating vibration between the initial state and the preset state, the vibration unit 10 drives the air to produce sound.

[0030] like Figure 1 and Figure 2 As shown, in this embodiment, the diaphragm 11 of the vibrating unit 10 of the sound-generating unit 10 includes a flexible substrate 111, a shape memory alloy driving element 112, and a composite layer 113 stacked sequentially from bottom to top. Understandably, the shape memory alloy driving element 112 is a driving element made of shape memory alloy material, possessing the characteristic of undergoing a reversible phase transition when the temperature changes, thereby generating a large deformation and a huge driving force. A mounting cavity is formed within the housing 30, and a mounting opening is formed on the upper side of the mounting cavity. The vibrating unit 10 is disposed at the mounting opening to cover it. The vibrating unit 10 extends in the left-right direction, and the flexible substrate 111 is mounted on both sides of the extending direction of the vibrating unit 10, that is, the left and right edges of the flexible substrate 111 are mounted on the housing 30, realizing the assembly between the vibrating unit 10 and the housing 30. The vibrating unit 10 can vibrate in the up-down direction, the mounting opening serves as a clearance, and the mounting cavity provides vibration space for the vibrating unit 10.

[0031] The heating module 21 and heat dissipation module 22 of the temperature control unit 20 are both mounted on the housing 30, resulting in a compact structure and small footprint. The heating module 21 includes an electrically connected power amplifier and a signal modulation module, with the power amplifier electrically connected to the shape memory alloy driver 112.

[0032] During operation, the sound-generating unit 100 of this invention transmits an audio signal via a signal modulation module. The signal modulation module converts the audio signal into a pulse width modulation (PWM) signal or a pulse amplitude modulation (PAM) signal proportional to the amplitude of the audio signal. The PWM or PAM signal is amplified by a power amplifier and applied to the shape memory alloy component, causing the component to rapidly heat up due to the Joule effect, resulting in deformation. During this deformation, the vibration unit 10 is driven to vibrate from its initial state to a preset state, such as... Figure 3 and Figure 6 As shown. The heat dissipation module 22 dissipates heat from the shape memory alloy drive component 112 when the vibration unit 10 is in a preset state, causing the shape memory alloy drive component 112 to cool down, thereby driving the vibration unit 10 to return from the preset state to its initial state, as shown. Figure 3 and Figure 6 As shown. The vibration unit 10 drives the air to produce sound during the reciprocating vibration between the initial state and the preset state, thereby realizing electroacoustic conversion.

[0033] Understandably, the initial state refers to the original shape or position maintained by the vibration unit 10 at room temperature or ambient temperature when its shape memory alloy drive component 112 is in the martensitic phase, exhibiting good flexibility and deformability. The preset state refers to the stable shape or position reached by the vibration unit 10 after its shape memory alloy drive component 112 undergoes a phase transformation at a specific temperature (above the phase transformation temperature), at which point the shape memory alloy drive component 112 transforms into the austenitic phase. This state is a shape memory pre-set through a material heat treatment process. By controlling the temperature change of the shape memory alloy drive component 112, the shape memory alloy component undergoes repeated phase transformations, thereby driving the vibration unit 10 to vibrate back and forth between the initial state and the preset state, thus driving the diaphragm 11 to generate mechanical vibration. This design utilizes the shape memory effect of the shape memory alloy drive component 112 to directly convert electrical energy into mechanical energy through Joule heating, realizing the conversion of electrical energy into thermal energy into mechanical energy to generate sound.

[0034] In the sound-generating unit 100 of this invention, a shape memory alloy driving element 112 is disposed within the diaphragm 11, and a heating module 21 is provided. The audio signal, after being modulated by PWM or PAM by a signal modulation module, is then amplified by a power amplifier to heat the shape memory alloy driving element 112. This causes the shape memory alloy driving element 112 to heat up rapidly and deform, thereby driving the vibration unit 10 to vibrate rapidly from its initial state to a preset state. When the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy driving element 112. At this time, the heat dissipation module 22 dissipates heat from the shape memory alloy driving element 112, causing it to cool down rapidly and return to its pre-heating shape, thereby driving the vibration unit 10 to quickly return from the preset state to its initial state. When the vibration unit 10 returns to its initial state, the heat dissipation module can pause the heat dissipation of the shape memory alloy drive component 112. At this time, the heating module 21 acts on the shape memory alloy drive component 112 again to heat it, causing the shape memory alloy drive component 112 to heat up rapidly again and deform, thereby driving the vibration unit 10 to vibrate rapidly from the initial state to the preset state again. This cycle repeats, realizing the process of the vibration unit 10 vibrating back and forth between the initial state and the preset state to drive the air to produce sound.

[0035] The sound-generating unit 100 of this invention utilizes the heating module 21 and the heat dissipation module 22 in the temperature control unit 20 to heat and dissipate heat from the shape memory alloy driving component 112, respectively, thereby improving the heating and cooling efficiency of the shape memory alloy driving component 112. This allows the shape memory alloy driving component 112 to deform rapidly, thereby driving the vibration unit 10 to vibrate rapidly between the initial state and the preset state. This not only improves the response frequency but also overcomes the thermal inertia bottleneck of the shape memory alloy driving component 112, extending the effective sound emission frequency range of the vibration unit 10 to a wider mid-frequency band and significantly reducing distortion. Moreover, the signal modulation module of the heating module 21 can be optimized according to the characteristics of the shape memory alloy driving component 112. Nonlinear compensation of the shape memory alloy driving component 112 can significantly improve the frequency response accuracy and acoustic performance of the sound-generating unit 100. By optimizing the characteristics of the shape memory alloy driving component 112, the phase transition process of the shape memory alloy driving component 112 can be precisely controlled, making the vibration of the vibration unit 10 more linear, effectively reducing harmonic distortion and phase distortion, and improving the clarity and fidelity of the sound. At the same time, this compensation control can also improve the dynamic response capability of the 100-unit speaker, making the sound details richer, the transient response faster, the overall sound quality better, and achieving high-fidelity audio reproduction.

[0036] like Figure 3 As shown, in the first embodiment, when the vibration unit 10 is in the initial state, the shape memory alloy drive member 112 is a bent structure 112a (as shown). Figure 3As shown by the dashed line, the bent structure 112a has multiple sequentially arranged bends 1121 along the extension direction of the vibration unit 10; the shape memory alloy drive member 112 is configured to deform and gradually tighten during heating to eliminate all bends 1121, and form a smooth arc-shaped structure 112b convex in a direction away from the housing 30 when the vibration unit 10 is in a preset state (as shown by the dashed line). Figure 3 (shown by the solid line in the middle); the shape memory alloy drive 112 is also configured to deform during heat dissipation and gradually relax to reform all the bends 1121, and reset from the smooth arc structure 112b to the bent structure 112a when the vibration unit 10 is in the initial state; the shape of the vibration unit 10 always changes with the shape change of the shape of the shape memory alloy drive 112.

[0037] When the vibration unit 10 is in its initial state, the shape memory alloy drive member 112 is a bent structure 112a. The bent structure 112a forms multiple sequentially arranged bends 1121 along the extension direction of the vibration unit 10, i.e., the left-right direction. The audio signal, after being modulated by the PWM or PAM modulation module, is amplified by a power amplifier to heat the shape memory alloy drive member 112. During heating, the shape memory alloy drive member 112 deforms, gradually tightening to eliminate all bends 1121. When the vibration unit 10 is in its preset state, it forms a smooth arc-shaped structure 112b. This smooth arc-shaped structure 112b protrudes away from the housing 30, i.e., protrudes upwards. The shape of the vibration unit 10 changes with the shape of the shape memory alloy drive member 112 under its drive, changing from the bent structure 112a in the initial state to the smooth arc-shaped structure 112b in the preset state.

[0038] When the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy drive component 112. At this time, the heat dissipation module 22 dissipates heat from the shape memory alloy drive component 112 to cool it down, causing it to cool down and deform again during the heat dissipation process. Specifically, during the deformation process, it gradually relaxes and reforms all the bends 1121. When the vibration unit 10 is in the initial state, it resets from the smooth arc structure 112b to the bent structure 112a, that is, it returns to the shape before heating. The shape of the vibration unit 10 changes with the shape of the shape memory alloy drive component 112 under the drive of the drive component 112, returning from the smooth arc structure 112b in the preset state to the bent structure 112a in the initial state.

[0039] This embodiment utilizes the effective and accurate coordination between the heating module 21 and the heat dissipation module 22, as well as the shape memory effect of the shape memory alloy driving component 112, to enable the shape memory alloy driving component 112 to quickly switch its form between heating and cooling. Specifically, its form rapidly changes between a bent structure 112a and a smooth arc structure 112b. The form of the vibration unit 10 changes along with the shape of the shape memory alloy driving component 112 under its drive, and can rapidly switch between the bent structure 112a and the smooth arc structure 112b, realizing the process of rapidly reciprocating vibration between the initial state and the preset state to drive the air to produce sound.

[0040] In the first embodiment, as Figure 2 and Figure 3 As shown, the bent structure 112a has multiple peaks 1122 and multiple troughs 1123 alternately formed along the extension direction of the vibration unit 10, and each peak 1122 and each trough 1123 is a bend 1121; the shape memory alloy drive member 112 is configured to deform and gradually tighten during the heating process, so that each peak 1122 and each trough 1123 can be flattened and all bends 1121 can be eliminated, and a smooth arc structure 112b is formed when the vibration unit 10 is in a preset state; the shape memory alloy drive member 112 is also configured to deform and gradually relax during the heat dissipation process, so as to reform the multiple peaks 1122 and multiple troughs 1123 alternately distributed along the extension direction of the vibration unit 10, and reset from the smooth arc structure 112b to the bent structure 112a when the vibration unit 10 is in the initial state.

[0041] When the vibration unit 10 is in its initial state, the shape memory alloy driving component 112 is a bent structure 112a, which alternately forms multiple peaks 1122 and multiple troughs 1123 in the left-right direction. The audio signal, after being modulated by PWM or PAM by the signal modulation module, is amplified by a power amplifier to heat the shape memory alloy driving component 112. During heating, the shape memory alloy driving component 112 deforms, gradually tightening to flatten the peaks 1122 and troughs 1123, thus eliminating all bends 1121. When the vibration unit 10 is in its preset state, it forms a smooth, upward-protruding arc-shaped structure 112b. The shape of the vibration unit 10 changes with the shape of the shape memory alloy driving component 112 under its drive, changing from the bent structure 112a in the initial state to the smooth arc-shaped structure 112b in the preset state.

[0042] When the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy drive component 112. At this time, the heat dissipation module 22 dissipates heat from the shape memory alloy drive component 112 to cool it down, causing it to cool down and deform again during the heat dissipation process. Specifically, during the deformation process, it gradually relaxes to reform multiple peaks 1122 and multiple troughs 1123 that are alternately distributed in the left and right directions, that is, to reform all the bends 1121. When the vibration unit 10 is in the initial state, it resets from the smooth arc structure 112b to the bent structure 112a, that is, it returns to the shape before heating. The shape of the vibration unit 10 changes with the shape of the shape memory alloy drive component 112 under the drive of the shape memory alloy drive component 112, returning from the smooth arc structure 112b in the preset state to the bent structure 112a in the initial state.

[0043] In the first embodiment, when the shape memory alloy drive component 112 is in a bent structure 112a, multiple peaks 1122 and multiple troughs 1123 are alternately formed along the extension direction of the vibration unit 10, so that the shape memory alloy drive component 112 is longer, and a longer driving stroke and greater driving force can be obtained within a limited area. Moreover, by adopting an alternating structure of multiple peaks 1122 and multiple troughs 1123, the shape memory alloy drive component 112 can not only make fuller use of the volume change during the phase change process, converting thermal energy or electrical energy into mechanical energy more efficiently, reducing energy loss and improving energy conversion efficiency, but also improve the overall stiffness and fatigue resistance of the shape memory alloy drive component 112, maintain structural integrity during repeated phase changes, and extend service life.

[0044] In one example, such as Figure 3 As shown, when the shape memory alloy driving component 112 is in a bent structure 112a, it is formed along the left-right direction by alternating arrangements of a peak 1122 and a trough 1123. That is, there is a trough 1123 between any two adjacent peaks 1122, and a peak 1122 between any two adjacent troughs 1123. Both the peak 1122 and the trough 1123 are bends 1121. In other examples, when the shape memory alloy driving component 112 is in a bent structure 112a, it is formed along the left-right direction by alternating arrangements of N peaks 1122 and n troughs 1123. Here, N and n are both integers greater than 1, N = n, or N ≠ n. For example, when N is 2 and n is 1, there is a pair of consecutive peaks 1122 between any two adjacent troughs 1123, and a trough 1123 between any two adjacent pairs of peaks 1122.

[0045] In the sound-generating unit 100 of this invention, when the shape memory alloy driving component 112 has a bent structure 112a, the distribution of the specific peaks 1122 and troughs 1123 can be flexibly selected according to actual usage requirements. Furthermore, when the shape memory alloy driving component 112 has a bent structure 112a, the dimensions of the peaks 1122, such as the height and width of the peaks 1122, and the dimensions of the troughs 1123, such as the depth and width of the troughs 1123, can also be flexibly selected according to usage requirements. Figure 1 and Figure 3 , Figure 4 and Figure 5 As shown.

[0046] In the second embodiment, when the vibration unit 10 is in the initial state, the shape memory alloy drive member 112 is a first bent structure 112c (e.g., Figure 6 As shown by the dashed line), the first bent structure 112c has multiple sequentially arranged first bends 1124 formed along the extension direction of the vibration unit 10; the shape memory alloy drive member 112 is configured to deform during heating, causing all the first bends 1124 to bend in the opposite direction, so that the shape of each first bend 1124 changes to the shape of the second bend 1127, and a second bent structure 112d is formed when the vibration unit 10 is in a preset state (as shown by the dashed line). Figure 6 (As shown by the solid line in the middle), wherein the second bent structure 112d forms a plurality of sequentially arranged second bends 1127 along the extension direction of the vibration unit 10, each second bend 1127 being formed by bending the corresponding first bend 1124 in the reverse direction; the shape memory alloy drive member 112 is also configured to deform during the heat dissipation process, causing all the second bends 1127 to bend in the reverse direction, so that the shape of each second bend 1127 changes to the shape of the first bend 1124, and resets from the second bent structure 112d to the first bent structure 112c when the vibration unit 10 is in the initial state; the shape of the vibration unit 10 always changes with the shape change of the shape of the shape memory alloy drive member 112.

[0047] When the vibration unit 10 is in the initial state, the shape memory alloy drive component 112 is a first bent structure 112c. The first bent structure 112c forms multiple sequentially arranged first bends 1124 along the extension direction of the vibration unit 10, that is, the left and right direction. After the audio signal is modulated by PWM or PAM by the signal modulation module, it is applied to the memory alloy driver 112 by the power amplifier to heat the memory alloy driver 112. During the heating process, the memory alloy driver 112 heats up and deforms. Specifically, during the deformation process, all its first bends 1124 are bent in the opposite direction so that the shape of each first bend 1124 is transformed into the shape of the second bend 1127. When the vibration unit 10 is in the preset state, a second bent structure 112d is formed. The second bent structure 112d has a plurality of second bends 1127 arranged sequentially in the left and right direction. Each second bend 1127 is formed by bending the corresponding first bend 1124 in the opposite direction. That is, the second bent structure 112d and the first bent structure 112c can be arranged in a mirror image. The shape of the vibration unit 10 changes with the shape of the shape of the shape memory alloy drive 112 under the drive of the shape memory alloy drive 112, changing from the first bent structure 112c in the initial state to the second bent structure 112d in the preset state.

[0048] When the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy drive component 112. At this time, the heat dissipation module 22 dissipates heat from the shape memory alloy drive component 112 to cool it down, causing it to cool down. During the heat dissipation process, it deforms again. Specifically, during the deformation process, all the second bends 1127 are bent in the opposite direction, causing the shape of each second bend 1127 to change towards the shape of the first bend 1124. When the vibration unit 10 is in the initial state, it resets from the second bent structure 112d to the first bent structure 112c, that is, it returns to the shape before heating. The shape of the vibration unit 10 changes with the shape of the shape memory alloy drive component 112 under the drive of the drive component 112, returning from the preset state of the second bent structure 112d to the initial state of the first bent structure 112c.

[0049] The second embodiment utilizes the effective and accurate coordination between the heating module 21 and the heat dissipation module 22, as well as the shape memory effect of the shape memory alloy driving component 112, to enable the shape memory alloy driving component 112 to quickly switch its form between heating and cooling. Specifically, its form rapidly changes between a bent structure 112a and a smooth arc structure 112b. The form of the vibration unit 10 changes with the shape of the shape memory alloy driving component 112 under its drive, and can rapidly switch between a first bent structure 112c and a second bent structure 112d, thereby realizing the process of rapidly reciprocating vibration between the initial state and the preset state to drive the air to produce sound.

[0050] Compared to the second embodiment, the shape memory alloy driving component 112 in the first embodiment alternates between a bent structure 112a and a smooth arc-shaped structure 112b, which has the advantages of simple structure and easy manufacturing, thus reducing manufacturing costs. This method has a short phase change path, fast response speed, and high heat conduction efficiency, making it suitable for applications requiring high response speed. Simultaneously, the stress distribution is relatively uniform, the fatigue life is long, and the reliability is good, making it suitable for applications requiring long-term stable operation.

[0051] Compared to the first embodiment, the second embodiment's shape memory alloy drive component 112 alternates between a first bent structure 112c and a second bent structure 112d, which are mirror images of each other. This significantly increases the drive stroke and output force, and improves the stability and energy conversion efficiency of the structure. The mirror transformation between the first bent structure 112c and the second bent structure 112d enables fuller utilization of the shape memory effect, thereby optimizing the drive performance.

[0052] In the second embodiment, the first bent structure 112c is alternately formed with multiple first peaks 1125 and multiple first troughs 1126 along the extension direction of the vibration unit 10, and each first peak 1125 and each first trough 1126 is a first bend 1124; the shape memory alloy drive member 112 is configured to deform during heating so that all the first peaks 1125 and all the first troughs 1126 bend in the opposite direction, so that the shape of each first peak 1125 and each first trough 1126 corresponds to the second trough 1129 and the second peak 1126, respectively. The shape of 28 changes, and when the vibration unit 10 is in a preset state, a second bent structure 112d is formed; the shape memory alloy drive 112 is also configured to deform during heat dissipation so that all the second peaks 1128 and all the second valleys 1129 bend in the opposite direction, so that the shape of each second peak 1128 and each second valley 1129 changes to the shape of the first valley 1126 and the first peak 1125 respectively, and is reset from the second bent structure 112d to the first bent structure 112c when the vibration unit 10 is in the initial state.

[0053] When the vibration unit 10 is in its initial state, the shape memory alloy driving component 112 is a first bent structure 112c, which alternately forms multiple first peaks 1125 and multiple first troughs 1126 in the left-right direction. After the audio signal is modulated by PWM or PAM by the signal modulation module, it is applied to the shape memory alloy driving component 112 by the power amplifier to heat the shape memory alloy driving component 112. During the heating process, the shape memory alloy driving component 112 heats up and deforms. Specifically, during the deformation process, all its first peaks 1125 and all its first troughs 1126 bend in opposite directions, so that the shape of each first peak 1125 and each first trough 1126 is transformed into the shape of the second trough 1129 and the second peak 1128, respectively, and a second bent structure 112d is formed when the vibration unit 10 is in the preset state. The shape of the vibration unit 10 changes with the shape of the shape of the shape memory alloy drive 112 under the drive of the shape memory alloy drive 112, changing from the first bent structure 112c in the initial state to the second bent structure 112d in the preset state.

[0054] When the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy drive component 112. At this time, the heat dissipation module 22 dissipates heat from the shape memory alloy drive component 112 to cool it down, causing the shape memory alloy drive component 112 to cool down. During the heat dissipation process, it deforms again. Specifically, during the deformation process, all the second peaks 1128 and all the second troughs 1129 are bent in the opposite direction, so that the shape of each second peak 1128 and each second trough 1129 corresponds to the shape of the first trough 1126 and the first peak 1125, respectively, to re-form multiple first peaks 1125 and multiple first troughs 1126 that are alternately distributed in the left and right direction, that is, to re-form all the first bends 1124. When the vibration unit 10 is in the initial state, the vibration unit 10 resets from the second bent structure 112d to the first bent structure 112c, that is, it returns to the shape before heating. The shape of the vibration unit 10 changes with the shape of the shape of the shape memory alloy drive 112 under the drive of the shape memory alloy drive 112, and returns from the second bent structure 112d in the preset state to the first bent structure 112c in the initial state.

[0055] In the second embodiment, when the shape memory alloy drive member 112 is in the form of a first bent structure 112c, multiple first peaks 1125 and multiple first troughs 1126 are alternately formed along the extension direction of the vibration unit 10. When the shape memory alloy drive member 112 is in the form of a second bent structure 112d, multiple second peaks 1128 and multiple second troughs 1129 are alternately formed along the extension direction of the vibration unit 10. The second bent structure 112d and the first bent structure 112c are mirror images of each other, so that the length of the shape memory alloy drive member 112 is further increased compared with the first embodiment, and a longer driving stroke and a greater driving force can be obtained within a limited area. Furthermore, by employing an alternating structure of multiple first peaks 1125 and multiple first troughs 1126 or an alternating arrangement of multiple second peaks 1128 and multiple second troughs 1129, the shape memory alloy drive component 112 can not only make fuller use of the volume change during the phase change process to convert thermal or electrical energy into mechanical energy more efficiently, reducing energy loss and improving energy conversion efficiency, but also improve the overall stiffness and fatigue resistance of the shape memory alloy drive component 112, maintain structural integrity during repeated phase changes, and extend its service life.

[0056] In one embodiment, the shape memory alloy drive 112 is a shape memory alloy wire or a shape memory alloy film, which is laid on the surface of the flexible substrate 111 facing the composite layer 113 along the extension direction of the flexible substrate 111.

[0057] When the shape memory alloy actuator 112 is a shape memory alloy wire, it has a high specific surface area, fast thermal response, and high phase change efficiency, making it suitable for rapid actuation applications. When the shape memory alloy actuator 112 is a shape memory alloy film, it has a larger actuation area, enabling it to generate greater driving force and deformation displacement, while also facilitating integration into microelectromechanical systems (MEMS). Both can fully utilize the shape memory effect to achieve precise deformation control, and their simple structure and low cost make them suitable for miniaturized and integrated actuation scenarios.

[0058] Furthermore, the shape memory alloy wires or films are laid along the extension direction of the flexible substrate 111 on the surface of the flexible substrate 111 facing the composite layer 113, that is, laid along the left-right direction of the flexible substrate 111 on the upper surface of the flexible substrate 111. This not only extends the laying length of the shape memory alloy wires or films, but also forms a tight laminated structure with the flexible substrate 111 and the composite layer 113. This allows full utilization of the phase deformation of the shape memory alloy wires or films, and through the constraint of the flexible substrate 111 and the composite layer 113, converts in-plane deformation into out-of-plane vibration, significantly improving the driving efficiency and output force of the diaphragm 11. At the same time, this laminated structure enhances the overall stiffness and stability of the diaphragm 11, making the vibration more uniform and facilitating miniaturized integration.

[0059] In one embodiment, the shape memory alloy driver 112 is electrically connected to the power amplifier via two electrodes 114. This connection method is simple in structure, highly reliable, and enables stable electrical signal transmission, ensuring that the shape memory alloy driver 112 receives sufficient driving power. The arrangement of the two electrodes 114 facilitates integration and packaging, reduces manufacturing costs, and simultaneously reduces contact resistance, thereby improving energy conversion efficiency. This connection method is suitable for the electrical connection requirements of various shape memory alloy driver 112s, exhibiting good versatility and practicality.

[0060] In one embodiment, when the vibration unit 10 is in the initial state, the shape memory alloy drive 112 is cooled to Ta, where Ta = Ms - T1, and Ms is the martensite initiation temperature, and T1 is at least 10°C; when the vibration unit 10 is in the preset state, the shape memory alloy drive 112 is heated to Tb, where Tb = Af + T2, and Af is the austenite termination temperature, Af is greater than Ms, and T2 is at least 10°C.

[0061] Understandably, when the vibration unit 10 is in its initial state, the temperature Ta of the shape memory alloy drive component 112 is at least 10°C lower than the martensite initiation temperature Ms, ensuring that the vibration unit 10 is entirely in the martensite phase in its initial state. When the vibration unit 10 is in its preset state, the temperature Tb of the shape memory alloy drive component 112 is at least 10°C higher than the austenite termination temperature Af, ensuring that the vibration unit 10 is entirely in the austenite phase in its initial state.

[0062] The above-described configuration precisely controls the temperature of the shape memory alloy drive component 112 outside its phase transformation temperature range, ensuring it is entirely in the martensitic phase in the initial state and entirely in the austenitic phase in the preset state, thereby achieving stable and repeatable deformation drive. The settings of T1 and T2 effectively avoid incomplete or partial phase transformation, improving drive reliability and response consistency. This temperature control strategy enables the vibration unit 10 to achieve precise reciprocating vibration with stable drive performance.

[0063] In one embodiment, such as Figure 1As shown, the heat dissipation module 22 includes a cooling pump 221, a microfluidic channel 222, and a heat sink 223. The outlet of the cooling pump 221 is connected to the inlet of the microfluidic channel 222, and the outlet of the microfluidic channel 222 is connected to the inlet of the cooling pump 221. A heat sink 223 is provided along the path connecting the outlet of the microfluidic channel 222 and the inlet of the cooling pump 221, so that the cooling pump 221, the microfluidic channel 222, and the heat sink 223 form a circulating heat dissipation system. The cooling pump 221 is installed on the housing 30 and is used to pump coolant into the microfluidic channel 222. The microfluidic channel 222 is disposed on the flexible substrate 111 corresponding to the shape memory alloy driving component 112, so as to absorb the heat of the shape memory alloy driving component 112 through the coolant flowing inside it and dissipate heat from the shape memory alloy driving component 112. The heat sink 223 is disposed on the outer periphery of the housing 30 or the flexible substrate 111 and is used to dissipate heat from the coolant.

[0064] Understandably, when the vibration unit 10 is in the preset state, the heating module 21 stops acting on the shape memory alloy drive component 112. At this time, the cooling pump 221 pumps coolant into the microfluidic channel 222. The microfluidic channel 222 is set on the flexible substrate 111 corresponding to the shape memory alloy drive component 112, so that the coolant flowing inside absorbs the heat of the shape memory alloy drive component 112 and dissipates heat from the shape memory alloy drive component 112, thereby achieving the cooling of the shape memory alloy drive component 112. Furthermore, a heat dissipation component 223 is provided on the path connecting the outlet of the microfluidic channel 222 and the inlet of the cooling pump 221. The heat dissipation component 223 can dissipate the heat absorbed by the coolant in the microfluidic channel, thereby cooling the coolant. This allows the coolant to be pumped back to the microfluidic channel 222 and absorb the heat from the shape memory alloy drive component 112 again as it flows within the microfluidic channel 222. This achieves a cyclic heat dissipation process for the shape memory alloy drive component 112, accelerates the recovery of the drive vibration unit 10 from the preset state to the initial state, and thus accelerates the phase change process and improves the response speed.

[0065] A circulating cooling system is formed by a cooling pump 221, microfluidic channels 222, and a heat sink 223. The cooling pump 221 drives the coolant to circulate in the microfluidic channels 222 to circulate and dissipate heat from the shape memory alloy driving component 112. This rapidly removes the heat generated by the shape memory alloy driving component 112, and the heat sink 223 provides efficient heat dissipation, forming a complete closed-loop cooling circuit. This ensures continuous and rapid cooling of the shape memory alloy driving component 112 as the vibration unit 10 recovers from its preset state to its initial state. This circulating cooling method achieves a continuous and stable cooling effect, ensuring precise temperature control of the shape memory alloy driving component 112 during the phase change process and avoiding performance degradation caused by overheating.

[0066] like Figure 1As shown, the heat sink 223 can be set on the housing 30 or on the outer periphery of the flexible substrate 111. The setting is reasonable and facilitates heat dissipation.

[0067] In one embodiment, the microfluidic channel 222 is disposed on the surface of the flexible substrate 111 facing the shape memory alloy drive member 112 and is matched with the extension path of the shape memory alloy drive member 112. The shape memory alloy drive member 112 is attached to or passes through the outer wall of the microfluidic channel 222, and a thermally conductive insulating member is also disposed between the shape memory alloy drive member 112 and the microfluidic channel 222.

[0068] The microfluidic channel 222 is disposed on the surface of the flexible substrate 111 facing the shape memory alloy driving component 112, that is, the microfluidic channel 222 is disposed on the upper surface of the flexible substrate 111, and the extension path of the microfluidic channel 222 is matched with that of the shape memory alloy driving component 112. This allows the coolant in the microfluidic channel 222 to flow uniformly along the extension path of the shape memory alloy driving component 112, thereby achieving an efficient and uniform cooling effect on the shape memory alloy driving component 112. This ensures that the temperature distribution of the shape memory alloy driving component 112 is consistent during the phase change process, and avoids performance degradation caused by local overheating or uneven cooling.

[0069] Furthermore, the thermally conductive insulating component achieves both efficient heat conduction and electrical insulation between the shape memory alloy drive component 112 and the microfluidic channel 222. This ensures rapid cooling of the shape memory alloy drive component 112 by the coolant while avoiding the risk of short circuits in the electrical signal. The shape memory alloy drive component 112 is attached to or passes through the microfluidic channel 222, allowing the coolant to indirectly contact the shape memory alloy drive component 112 through the thermally conductive insulating component or to directly contact it, significantly improving heat exchange efficiency and shortening the phase change response time. Simultaneously, this design is compact and easy to integrate.

[0070] In the heat dissipation module 22 of the sound-generating unit 100 of this invention, the heat sink 223 is at least one of a semiconductor cooler, a micro fan, or heat sink fins, which can be flexibly configured according to different application scenarios and heat dissipation requirements to achieve optimal heat dissipation effect. The semiconductor cooler can achieve active cooling and is suitable for high power density scenarios; the micro fan dissipates heat through forced convection, resulting in high heat dissipation efficiency; the heat sink fins have a simple structure and low cost, making them suitable for space-constrained miniaturized applications. This diverse selection of heat dissipation solutions enables the circulating heat dissipation system to adapt to different working conditions and environmental requirements, ensuring precise temperature control of the shape memory alloy drive component 112 during phase change, and improving the reliability and service life of the circulating heat dissipation system.

[0071] In one embodiment, the vibration unit 10 further includes folded rings 12, with two folded rings 12 connected to each end of the diaphragm 11. The end of each folded ring 12 furthest from the diaphragm 11 is mounted on the housing 30 via a support member 13. Figure 1 As shown, two folded rings 12 are connected to the front and rear ends of the diaphragm 11, respectively. The end of each ring away from the diaphragm 11 is mounted on the housing 30 via a support member 13, specifically at the edge of the mounting opening of the housing 30. The support member 13 can be matched with the shape of the corresponding mounting opening edge to improve the assembly stability with the housing 30, thereby improving the assembly stability of the vibration unit 10 and the housing 30. The folded rings 12 provide elastic support for the diaphragm 11, enabling the diaphragm 11 to reciprocate in the vertical direction, while limiting the radial displacement of the diaphragm 11 to ensure the consistency of the vibration direction. Furthermore, the elastic deformation of the folded rings 12 can store and release energy, improving the vibration efficiency of the diaphragm 11.

[0072] In one embodiment, the flexible substrate 111 is a polyimide film or thermally conductive rubber, which has high strength, high temperature resistance and good thermal conductivity, can withstand the thermal stress during the phase change of the shape memory alloy drive 112, accelerate the thermal response speed, and ensure structural stability, while facilitating processing and integration.

[0073] In one embodiment, the shape memory alloy actuator 112 is a nitinol shape memory alloy wire or a nitinol shape memory alloy film, which has shape memory effect and superelasticity, and can achieve reversible phase transformation through temperature change to generate stable deformation drive. Nitinol materials have excellent fatigue life, corrosion resistance and biocompatibility, and are suitable for precision drive and miniaturization applications.

[0074] In one embodiment, the composite layer 113 includes a porous structure layer and a sealing film, wherein the porous structure layer is stacked on the shape memory alloy drive member 112, and the sealing film is composited on the surface of the porous structure layer facing away from the shape memory alloy drive member 112; the porous structure layer is a carbon fiber woven mesh or a porous metal foam.

[0075] Specifically, a porous structure layer is stacked on top of the shape memory alloy driving component 112, and a sealing film is laminated onto the upper surface of the porous structure layer. The porous structure layer, made of carbon fiber woven mesh or porous metal foam, possesses high porosity and good mechanical strength, providing stable support and cushioning for the shape memory alloy driving component 112. The sealing film, laminated onto the upper surface of the porous structure layer, seals the voids in the porous structure layer, ensuring acoustic performance. The porous structure layer, made of carbon fiber woven mesh or porous metal foam, is lightweight, high-strength, has high porosity, and good heat resistance, allowing it to fit tightly against the shape memory alloy driving component 112, stably supporting the shape memory alloy component, adapting to high-frequency deformation, and facilitating heat dissipation and weight reduction.

[0076] In the sound-generating unit 100 of the present invention, the flexible substrate 111, the shape memory alloy driving component 112, and the composite layer 113 of the diaphragm 11 can all be made of the above-mentioned flexible materials, so that the diaphragm 11 has the characteristics of being thin, flexible, and stretchable, and is easy to integrate into flexible products such as clothing and rollable screens.

[0077] Specifically, in one embodiment, the flexible substrate 111 is a 0.1 mm thick polyimide film or thermally conductive rubber, and the shape memory alloy drive component 112 is formed by bending a nickel-titanium shape memory alloy wire into the aforementioned periodic wave structure when the vibration unit 10 is in its initial state, and adhering it to the upper surface of the flexible substrate 111 with a pre-strain of 2%. The composite layer 113 is composed of a 50 μm thick carbon fiber woven mesh and a 10 μm thick polyester sealing film composited on the carbon fiber woven mesh.

[0078] In the heating module 21, the power amplifier is a Class D power amplifier. After the audio signal is input, the signal modulation module compares it with a high-frequency triangular wave to generate a PWM signal. The duty cycle of this PWM signal is proportional to the instantaneous amplitude of the audio signal. This PWM signal is then amplified by the Class D power amplifier and applied to the shape memory alloy wire.

[0079] In the heat dissipation module 22, the cooling pump 221 can be a miniature piezoelectric pump, which has the advantages of small size, low power consumption, fast response, and no electromagnetic interference. It is suitable for miniaturized and highly integrated drive systems and can achieve precise flow control. The coolant can be deionized water. Deionized water has good thermal conductivity and insulation, which can efficiently dissipate heat and prevent short circuits, while also being low in cost, safe and environmentally friendly.

[0080] The present invention also proposes an electronic device that uses the sound-generating unit 100 as described above. The specific structure and usage of the sound-generating unit 100 in this electronic device are as described in the above embodiments. Since this electronic device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0081] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any equivalent structural transformations made based on the inventive concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A sound-emitting monomer, characterized in that, The sound-generating unit includes: A vibration unit, the vibration unit including a diaphragm, the diaphragm including a flexible substrate, a shape memory alloy driving component and a composite layer stacked in sequence; The housing has a mounting cavity formed inside it, and a mounting opening is formed on one side of the mounting cavity. The vibration unit is disposed at the mounting opening, and the flexible substrate is mounted on the housing with its two edges along the extension direction of the vibration unit. A temperature control unit, comprising a heating module and a heat dissipation module, both mounted on the housing, wherein the heating module comprises an electrically connected power amplifier and a signal modulation module, and the power amplifier is electrically connected to the shape memory alloy driver; After the audio signal is modulated by the signal modulation module, it is amplified by a power amplifier to heat the shape memory alloy driver, causing it to deform and drive the vibration unit to vibrate from the initial state to the preset state. The heat dissipation module is used to dissipate heat from the shape memory alloy driver when the vibration unit is in the preset state, so that the shape memory alloy driver cools down and drives the vibration unit to return from the preset state to the initial state. The vibration unit drives the air to produce sound during the reciprocating vibration between the initial state and the preset state.

2. The sound-generating unit as described in claim 1, characterized in that, When the vibration unit is in the initial state, the shape memory alloy drive component is a bent structure, and the bent structure has multiple sequentially arranged bends along the extension direction of the vibration unit. The memory alloy drive is configured to deform and gradually tighten during heating to eliminate all the bends, and to form a smooth arc-shaped structure that bulges away from the housing when the vibration unit is in the preset state. The memory alloy drive is also configured to deform during heat dissipation and gradually relax to reform all the said bends, and to reset from the smooth arc structure to the bent structure when the vibration unit is in the initial state. The shape of the vibration unit always changes in accordance with the shape of the shape memory alloy drive component.

3. The sound-generating unit as described in claim 2, characterized in that, The bent structure alternately forms multiple peaks and multiple troughs along the extension direction of the vibration unit, and each peak and each trough is a bend. The memory alloy drive is configured to deform and gradually tighten during heating, so that each of the crests and troughs can be flattened to eliminate all the bends, and to form the smooth arc structure when the vibration unit is in the preset state. The shape memory alloy drive is also configured to deform and gradually relax during heat dissipation to reform a plurality of wave peaks and a plurality of wave troughs that are alternately distributed along the extension direction of the vibration unit, and to reset from the smooth arc structure to the bent structure when the vibration unit is in the initial state.

4. The sound-generating unit as described in claim 1, characterized in that, When the vibration unit is in the initial state, the shape memory alloy drive component is a first bent structure, and the first bent structure has a plurality of sequentially arranged first bends along the extension direction of the vibration unit. The shape memory alloy drive is configured to deform during heating so that all the first bends are bent in the opposite direction, so that the shape of each first bend is transformed into the shape of a second bend, and a second bend structure is formed when the vibration unit is in the preset state. The second bend structure has a plurality of second bends arranged sequentially along the extension direction of the vibration unit, and each second bend is formed by bending the corresponding first bend in the opposite direction. The memory alloy drive is also configured to deform during heat dissipation to cause all the second bends to bend in the opposite direction, so that the shape of each second bend changes to the shape of the first bend, and resets from the second bend structure to the first bend structure when the vibration unit is in the initial state. The shape of the vibration unit always changes in accordance with the shape of the shape memory alloy drive component.

5. The sound-generating unit as described in claim 4, characterized in that, The first bent structure alternately forms multiple first peaks and multiple first troughs along the extension direction of the vibration unit, and each first peak and each first trough is a first bend. The shape memory alloy drive is configured to deform during heating so that all the first peaks and all the first troughs bend in the opposite direction, so that the shape of each first peak and each first trough is transformed into the shape of the second trough and the second peak respectively, and the second bent structure is formed when the vibration unit is in the preset state. The shape memory alloy drive is also configured to deform during heat dissipation, causing all the second peaks and all the second troughs to bend in opposite directions, so that the shapes of each second peak and each second trough correspond to the shapes of the first trough and the first peak, respectively, and to reset from the second bent structure to the first bent structure when the vibration unit is in the initial state.

6. The sound-generating unit as described in any one of claims 1 to 5, characterized in that, The memory alloy driving component is a memory alloy wire or a memory alloy film, and the memory alloy wire or the memory alloy film is laid on the surface of the flexible substrate facing the composite layer along the extension direction of the flexible substrate; And / or, the shape memory alloy driver is electrically connected to the power amplifier via two electrodes.

7. The sound-generating unit as described in any one of claims 1 to 5, characterized in that, When the vibration unit is in the initial state, the shape memory alloy drive is cooled to Ta, where Ta = Ms - T1, and Ms is the martensite initiation temperature and T1 is at least 10°C. When the vibration unit is in the preset state, the shape memory alloy drive component is heated to Tb, where Tb = Af + T2, Af is the austenite termination temperature, Af is greater than Ms, and T2 is at least 10°C.

8. The sound-generating unit as described in any one of claims 1 to 5, characterized in that, The heat dissipation module includes a cooling pump, a microfluidic pipe, and a heat dissipation component. The outlet of the cooling pump is connected to the inlet of the microfluidic pipe, the outlet of the microfluidic pipe is connected to the inlet of the cooling pump, and the heat dissipation component is provided on the path connecting the outlet of the microfluidic pipe and the inlet of the cooling pump, so that the cooling pump, the microfluidic pipe, and the heat dissipation component form a circulating heat dissipation system. The cooling pump is installed in the housing and is used to pump coolant into the microfluidic channel. The microfluidic channel is disposed on the flexible substrate corresponding to the shape memory alloy driving component, so as to absorb the heat of the shape memory alloy driving component through the coolant flowing inside it and dissipate heat from the shape memory alloy driving component. The heat dissipation component is disposed on the outer peripheral edge of the housing or the flexible substrate and is used to dissipate heat from the coolant.

9. The sound-generating unit as described in claim 8, characterized in that, The microfluidic channel is disposed on the surface of the flexible substrate facing the shape memory alloy driver and is matched with the extension path of the shape memory alloy driver. The shape memory alloy driver is attached to or passes through the outer wall of the microfluidic channel, and a thermally conductive insulating component is also disposed between the shape memory alloy driver and the microfluidic channel. And / or, the heat sink is at least one of a semiconductor cooler, a micro fan, or a heat sink fin.

10. The sound-generating unit as described in any one of claims 1 to 5, characterized in that, The vibration unit further includes folded rings, and two folded rings are respectively connected to both ends of the diaphragm. The end of each folded ring away from the diaphragm is mounted on the housing by a support member. And / or, the flexible substrate is a polyimide film or thermally conductive rubber; And / or, the memory alloy drive is a nitinol memory alloy wire or a nitinol memory alloy film; And / or, the composite layer includes a porous structure layer and a sealing film, wherein the porous structure layer is stacked on the shape memory alloy drive component, and the sealing film is composited on the surface of the porous structure layer opposite to the shape memory alloy drive component; the porous structure layer is a carbon fiber woven mesh or a porous metal foam.

11. An electronic device, characterized in that, The electronic device uses a sound-generating unit as described in any one of claims 1 to 10.

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