MEMS air-cooled heat dissipation device and use method thereof

Abstract

The invention provides an MEMS air-cooled heat dissipation device and a use method thereof.The MEMS air-cooled heat dissipation device comprises a shell, a micro-valve assembly and a motion execution assembly, the micro-valve assembly comprises a cantilever beam, a first partition plate and an air chamber, an actuator is attached to the cantilever beam to generate driving force in the normal direction on the cantilever beam, and therefore a through hole is selectively opened or closed through the cantilever beam; the motion executing assembly comprises a second partition plate, the second partition plate is attached to the shell to separate the first fluid chamber and the second fluid chamber, the second partition plate comprises an opening, and the vibrating diaphragm and the piezoelectric actuator are arranged on the opening in a crossing mode. The actuator and the cantilever beam are used for constructing the active one-way micro-valve assembly, the active one-way micro-valve assembly is matched with the motion execution assembly, cooling gas is guided to the fluid chamber adjacent to the hot end of the electronic equipment in a one-way mode, then heated air is exhausted, the heat dissipation effect is achieved, ultrasonic waves generated by high working frequency and vibration of the piezoelectric film layer are inaudible, and the heat dissipation effect is good. The system has the advantages of no noise and low power consumption.

Description

Technical Field

[0001] The present invention relates to the field of digital sound generation, and in particular to a MEMS heat dissipation device and a use method thereof. Background Art

[0002] With the development of consumer electronics and semiconductor technology, electronic products have a trend towards miniaturization and high performance. Electronic products will generate a lot of heat during operation. If the heat is not dissipated in time, the heat accumulation will cause the temperature to rise rapidly, which will seriously affect the working efficiency of electronic components and even damage electronic products.

[0003] At present, the heat dissipation method of electronic products often uses cooling fans, which use cooling fans to generate airflow and transfer the high-temperature airflow near the hot end of the electronic product to the surrounding air through convection to assist in heat dissipation. This heat dissipation method requires the design of a mechanical fan, and the size and noise of the heat dissipation system will limit the design and application in miniaturized electronic products.

[0004] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present invention and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology section of the present invention. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a MEMS air-cooled heat dissipation device and a method of using the same, so as to solve the problems of the existing heat dissipation fan being large in size and making obvious noise during operation.

[0006] To achieve the above objectives and other related objectives, the present invention provides a MEMS air-cooled heat sink, comprising: A housing, the housing comprising a base, the housing being provided with an air inlet end and an air outlet end, the air inlet end being configured to introduce cooling gas; A one-way microvalve assembly, the one-way microvalve assembly comprising a cantilever beam, a first baffle and an air chamber separated by the first baffle, the air inlet end fluid is connected to the air chamber, a through hole on the first baffle is aligned with the cantilever beam to connect the air chamber fluid to the first fluid chamber, the cantilever beam is attached with a first actuator to generate a driving force in a normal direction on the cantilever beam, so as to realize the opening or closing operation of the through hole; A motion execution assembly, the motion execution assembly comprising a stacked second partition, a diaphragm and a second actuator, the second partition being attached to the housing to separate a first fluid chamber and a second fluid chamber, an opening being formed on the second partition, at least a portion of the diaphragm being suspended above the opening to bend under the drive of the second actuator, for achieving unidirectional flow of cooling gas along a first flow path, the first flow path comprising flowing from the air chamber through the first fluid chamber and into the second fluid chamber; Wherein, the second actuator is a piezoelectric actuator, the base is removably attached to the hot end of the electronic device; and the exhaust end is configured to provide fluid communication between the second fluid chamber and the external environment.

[0007] Optionally, the shell includes a top cover, and the cantilever beam includes a fixed part and a movable part, the fixed part is anchored on the top cover, and the movable part is suspended above the first partition and in direct contact with the first actuator; wherein the first actuator includes one of an electrostatic actuator and a piezoelectric actuator.

[0008] Optionally, the first actuator and the cantilever beam constitute an electrostatic ultrasonic transducer, which includes a top electrode attached to the cantilever beam and a bottom electrode mounted near the through hole. When a driving signal is applied between the top electrode and the bottom electrode, the movable part of the cantilever beam is caused to reciprocate around its fixed part toward or away from the first partition, thereby opening or closing the through hole.

[0009] Optionally, the second partition plate includes a vent hole offset relative to the through hole, for providing fluid communication between the first fluid chamber and the second fluid chamber.

[0010] Optionally, a control unit is further included, which is electrically connected to the first actuator and is used to provide a driving signal instructing the opening or closing of the one-way microvalve assembly.

[0011] Optionally, the motion execution component is configured as a piezoelectric micromechanical ultrasonic transducer, and the control unit is electrically connected to the piezoelectric micromechanical ultrasonic transducer to draw the cooling gas into the first fluid chamber when the diaphragm moves to a negative phase; or, to push the cooling gas to flow from the first fluid chamber into the second fluid chamber when the diaphragm moves to a positive phase.

[0012] Optionally, the exhaust port is configured as an opening located on a side wall of the second fluid chamber, for providing fluid communication between the second fluid chamber and an external environment.

[0013] Optionally, the air inlet end and the through hole are arranged on opposite sides of the air chamber; wherein the air inlet end is arranged as a plurality of air inlet holes penetrating the top cover.

[0014] The present invention also provides a method for using a MEMS air-cooled heat sink, comprising the following steps: The aforementioned MEMS air-cooled heat sink is attached to the hot end of the electronic device; The control unit applies a pulse sequence of a first driving signal and a second driving signal to the first actuator and the second actuator respectively, so that the cantilever beam and the diaphragm vibrate back and forth, wherein each pulse cycle includes a first time interval and a second time interval: wherein, In the first time interval, by making the second driving signal applied to the second actuator have a negative pulse phase, the cooling gas is introduced through the air inlet end while the one-way microvalve component is kept open; During the second time interval, a first drive signal is applied to the first actuator, causing the microvalve assembly to close to air-tightly isolate the air chamber from the first fluid chamber, and at the same time, a second drive signal applied to the second actuator has a positive pulse phase, causing a portion of the introduced cooling gas to flow from the first fluid chamber through the second fluid chamber and be discharged to the external environment.

[0015] Optionally, a plurality of MEMS air-cooled heat sinks are arranged in an array at the hot end of the electronic device, each of the plurality of MEMS air-cooled heat sinks having a lateral opening, and the plurality of MEMS air-cooled heat sinks are arranged so that the lateral opening of any MEMS air-cooled heat sink has an opening direction that is staggered with the lateral opening of an adjacent MEMS air-cooled heat sink.

[0016] As described above, the MEMS air-cooled heat sink of the present invention utilizes an actuator and a cantilever beam to construct an active one-way microvalve assembly, which cooperates with the motion execution assembly to guide the cooling gas in one direction to the fluid chamber adjacent to the hot end of the electronic device, thereby discharging the heated air to achieve a heat dissipation effect; the operating frequency of the piezoelectric film layer of the present invention is extremely high, and the ultrasonic wave generated by the vibration is inaudible. Compared with traditional air-cooled heat sinks, it has the advantages of no noise and low power consumption.

[0017] The MEMS air-cooled heat sink of the present invention is used by attaching one or more MEMS air-cooled heat sinks to the hot end of an electronic device, and utilizing the cooperation of a one-way microvalve assembly and a motion actuator assembly to guide the cooling gas to a fluid chamber adjacent to the hot end of the electronic device, thereby improving the convective heat exchange efficiency with the heated air. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1Shown is a structural schematic diagram of an example of a MEMS air-cooled heat dissipation device in an embodiment of the present invention.

[0019] Figure 2 Shown is a structural schematic diagram of another example of a MEMS air-cooled heat dissipation device in an embodiment of the present invention.

[0020] Figure 3 Shown is an exemplary top view of a MEMS air-cooled heat sink according to an embodiment of the present invention.

[0021] Figure 4 shows Figure 3 The working state diagram of the MEMS air-cooled heat sink when extracting cooling gas is shown; wherein, Figure 4A For a three-dimensional isometric diagram, Figure 4B For along Figure 4A Cutaway view of the section shown.

[0022] Figure 5 shows Figure 3 The working state diagram of the MEMS air-cooled heat sink is shown in the figure when discharging heated air; wherein, Figure 5A For a three-dimensional isometric diagram, Figure 5B For along Figure 5A Cutaway view of the section shown.

[0023] Figure 6 Shown is a schematic diagram of an array arrangement of MEMS air-cooled heat sinks in an embodiment of the present invention.

[0024] Figure 7 Shown is a diagram of relevant signal waveforms in the method of using the MEMS air-cooled heat sink in an embodiment of the present invention.

[0025] Component number description: 10-air chamber; 20-first fluid chamber; 30-second fluid chamber; 11-top cover; 12-cantilever beam; 13-electrostatic actuator; 101-air inlet; 21-first baffle; 31-second baffle; 32-diaphragm; 33-piezoelectric actuator; 211-through hole; 311-exhaust hole; 301-exhaust end; 41-base; g-heated air; t 1 - first time interval; t 2 - A second time interval. DETAILED DESCRIPTION

[0026] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0027] See also Figures 1 to 7It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the illustrations only show the components related to the present invention rather than the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0028] The present invention provides a MEMS air-cooled heat dissipation device, comprising a shell, a one-way microvalve assembly and a motion execution assembly, wherein the shell is provided with an air inlet end and an exhaust end, and the air inlet end is configured to introduce cooling gas; the one-way microvalve assembly comprises a cantilever beam, a first partition and an air chamber separated by the first partition, and is used to open or close the flow path from the air inlet end to the first fluid chamber.

[0029] The one-way microvalve assembly includes an air chamber, the air inlet end is connected to the one-way microvalve assembly to introduce cooling gas into the air chamber, and the cantilever beam is attached with a first actuator to generate a driving force in the normal direction on the cantilever beam to achieve the opening or closing operation of the through hole. Figure 1 and Figure 2 Schematic diagrams of the structure of the MEMS air-cooled heat sink are shown respectively. In some examples, the first actuator is configured as an electrostatic actuator to drive the cantilever beam to reciprocate toward or away from the first diaphragm when a driving signal (e.g., a driving voltage) is applied between the top electrode and the bottom electrode thereof. Alternatively, the first actuator can be configured as an actuator based on a piezoelectric film.

[0030] like Figure 1 As shown, the shell includes a top cover 11, and the top cover 11, the cantilever beam 12 and the first partition 21 jointly define an air chamber 10, the cantilever beam 12 includes a fixed portion and a movable portion, the fixed portion is anchored on the top cover 11, and the movable portion is suspended above the first partition and is in direct contact with the electrostatic actuator 13, and a through hole 211 is arranged on the first partition 21 to be aligned with the cantilever beam so that the fluid of the air chamber 10 is connected to the first fluid chamber 20.

[0031] The fixing portion of the cantilever beam can be anchored to the top cover 11, and an air inlet end and the through hole 211 are arranged on opposite sides of the air chamber. In some examples, the air inlet end is arranged to be a plurality of air inlet holes penetrating the top cover 11, such as Figure 3 As shown, the air inlet holes 101 are offset relative to the through holes along the spacing direction between the top cover and the first partition. The shape and arrangement of the air inlet holes 101 can be adjusted according to actual needs, for example, circular, square, hexagonal openings or openings of similar shapes arranged in an array. In a preferred example, as Figure 3As shown, the top cover 11 is generally configured as a disc-shaped top cover, and the top cover 11 is provided with a plurality of radially arranged air inlet holes 101. Furthermore, the number of the cantilever beams 12 and the connection method with the top cover can be flexibly adjusted according to needs, for example, at least one cantilever beam with double ends fixed, or at least two cantilever beams with single ends. Figure 3 As shown, the cantilever beam 12 is configured as a cantilever beam fixed at one end, and a plurality of cantilever beams 12 are attached around the electrostatic actuator 13 , and the gaps between adjacent cantilever beams can also be used to introduce cooling gas.

[0032] Or, as an alternative implementation, the top cover 11 itself is made of a breathable material, such as polytetrafluoroethylene (PTFE).

[0033] The motion execution component is configured to receive the cooling gas introduced by the one-way microvalve component and guide a portion of the introduced cooling gas from the first fluid chamber to the second fluid chamber. The motion execution component includes a stacked second partition, a diaphragm and a second actuator. The second partition is attached to the housing to separate the first fluid chamber from the second fluid chamber. An opening is provided in the second partition. Figure 1 As shown, the second actuator may be a piezoelectric actuator 33, the first fluid chamber 20 is defined between the first diaphragm 21 and the second diaphragm 31, the first diaphragm 21 and the second diaphragm 31 may be attached to the housing, the second diaphragm 31 includes an opening opened thereon, a diaphragm 32 and a piezoelectric actuator 33 are arranged across the opening, at least a portion of the diaphragm is suspended above the opening, and a bending motion occurs under the drive of the piezoelectric actuator, which is used to realize the unidirectional flow of cooling gas along the first flow path, so as to guide the cooling gas from the air chamber 10 to the first fluid chamber 20, and to guide a portion of the introduced cooling gas from the first fluid chamber 20 to the second fluid chamber 30; that is, the first flow path is configured so that the cooling gas flows from the air chamber through the first fluid chamber 20 and enters the second fluid chamber 30. The piezoelectric actuator is configured as an actuator based on a piezoelectric film, which uses the inverse piezoelectric effect of the piezoelectric film to convert simple harmonic vibration, and the operating frequency of the piezoelectric film layer is extremely high. In practical applications, the shell, the first partition plate and the second partition plate may be an integral structure or a combined structure, and such deformation has no substantial impact on this embodiment.

[0034] Continue to see Figure 1, the second partition plate 31 is also provided with an exhaust hole 311, and the exhaust hole 311 is configured to make the first fluid chamber 20 and the second fluid chamber 30 fluidly connected. Preferably, the exhaust hole 311 can be offset relative to the through hole 211 on the second partition plate, and the diaphragm 32 guides the cooling gas from the air inlet end to the first fluid chamber 20 when the through hole is in an open state, or exhausts the first fluid chamber 20 when the through hole 211 is in a closed state. In a preferred example, Figure 2 As shown, the exhaust hole 311 is also provided with a one-way valve 312, for example, a pneumatic one-way valve. When the pressure in the first fluid chamber is higher than the pressure in the second fluid chamber, the one-way valve 312 is opened to allow a portion of the cooling gas to be introduced into the second fluid chamber 30. On the contrary, when the pressure in the first fluid chamber is lower than or close to the pressure in the second fluid chamber, the one-way valve 312 is closed to prevent the heated gas from the hot end from being introduced back into the first fluid chamber 20.

[0035] The MEMS air-cooled heat sink also includes a control unit, which is electrically connected to the electrostatic actuator to provide a drive signal indicating that the one-way microvalve assembly is opened or closed. In some examples, the electrostatic actuator and the cantilever beam constitute an electrostatic ultrasonic transducer, and the electrostatic ultrasonic transducer includes a top electrode attached to the cantilever beam and a bottom electrode mounted near the through hole. The control unit applies a drive signal between the top electrode and the bottom electrode to cause the movable portion of the cantilever beam to reciprocate around its fixed portion toward or away from the first partition, thereby opening or closing the through hole. In a preferred example, the top electrode is configured to have an area smaller than that of the cantilever beam, and the bottom electrode can be arranged in a grid shape, for example, as Figure 2 As shown, the mesh electrodes are installed between the through holes. The driving signal applied here includes, for example, applying a DC bias between the top electrode and the bottom electrode of the electrostatic ultrasonic transducer, and a voltage superposition for generating an alternating voltage.

[0036] The motion execution component is configured as a piezoelectric micromechanical ultrasonic transducer, which may include alternately stacked piezoelectric film layers and electrode layers, wherein the electrode layers include a positive electrode layer and a negative electrode layer, and the diaphragm is in direct contact with one of the positive electrode layer and the negative electrode layer, and serves as an insulating layer between the electrode layer and the substrate, which can reduce parasitic capacitance. By applying a DC bias to the positive and negative electrode layers, and a voltage for generating an alternating voltage, the superposition of the two causes the piezoelectric film layer in the piezoelectric ultrasonic transducer to generate periodic mechanical vibrations, and the electric field energy is converted into mechanical energy, driving the diaphragm to vibrate mechanically at high frequency, and performing work on the gas in the first fluid chamber; that is, compressing or expanding the gas therein.

[0037] In some examples, the control unit is electrically connected to the piezoelectric micromechanical ultrasonic transducer, and is used to provide a driving signal instructing the piezoelectric micromechanical ultrasonic transducer to generate ultrasonic vibration, causing the diaphragm to generate a negative phase bending motion, increasing the gap between the first diaphragm and the diaphragm, and reducing the air pressure in the first fluid chamber, thereby drawing the cooling gas into the first fluid chamber; or causing the diaphragm to generate a positive phase bending motion, reducing the gap between the first diaphragm and the diaphragm, and increasing the air pressure in the first fluid chamber, thereby pushing the cooling gas to flow from the first fluid chamber into the second fluid chamber.

[0038] Fig. 4 is a working state diagram of the MEMS air-cooled heat sink when extracting cooling gas. As shown in Fig. 4, the electrostatic actuator 13 can work in the initial or non-actuated state, that is, the one-way microvalve assembly remains in the open state, the cantilever beam 12 is not subjected to driving force, and the piezoelectric film drives the diaphragm 22 to generate a negative phase bending motion, which can change the air pressure difference between the air chamber and the adjacent fluid chamber, so that the cooling gas is extracted into the air chamber 10 through the air inlet end.

[0039] FIG5 is a working state diagram of the MEMS air-cooled heat sink when discharging heated air. As shown in FIG5, the electrostatic actuator can work in an actuated state to drive the movable portion of the cantilever beam to deflect around its fixed portion toward the first partition. A through hole 211 is arranged on the first partition in alignment with the cantilever beam to allow the through hole to be closed when the cantilever beam abuts against the first partition, thereby adjusting the one-way microvalve assembly to a closed state. At the same time, controlled by the control unit, the piezoelectric film drives the diaphragm 22 to generate a positive phase bending motion, so that a portion of the introduced cooling gas is discharged from the first fluid chamber.

[0040] The MEMS air-cooled heat sink is removably attached to the hot end of the electronic device, and a second fluid chamber is defined between the second partition and the base, and the second fluid chamber is preferably configured as a one-way chamber. Figure 1 As shown, the exhaust port 301 is configured as a lateral opening located on the side wall of the second fluid chamber, for providing fluid communication between the second fluid chamber and the external environment.

[0041] This embodiment also provides a method for using the MEMS air-cooled heat sink described above, including steps S1 to S2. Figure 6~Figure 7 , the method of using this embodiment is introduced.

[0042] S1: attaching the aforementioned MEMS air-cooled heat sink to the hot end of the electronic device; S2: Using the control unit to apply a pulse sequence of a first driving signal and a second driving signal to the electrostatic actuator and the piezoelectric actuator respectively, so that the cantilever beam and the diaphragm vibrate back and forth, wherein each pulse cycle includes a first time interval and a second time interval: In the first time interval, by making the second driving signal applied to the piezoelectric actuator have a negative pulse phase, the cooling gas is introduced through the air inlet end while the one-way microvalve component remains open; During the second time interval, a first drive signal is applied to the electrostatic actuator, causing the one-way microvalve assembly to close to airtightly isolate the air chamber from the first fluid chamber, and at the same time, a second drive signal applied to the piezoelectric actuator has a positive pulse phase, causing a portion of the introduced cooling gas to flow from the first fluid chamber through the second fluid chamber and be discharged to the external environment.

[0043] Step S1: One or more MEMS air-cooled heat sinks may be fixed to the hot end of the electronic device using thermally conductive adhesive. Figure 6 As shown, multiple MEMS air-cooled heat sinks are arranged in an array at the hot end of the electronic device; preferably, each of the multiple MEMS air-cooled heat sinks has a lateral opening, and the lateral opening of one of the multiple MEMS air-cooled heat sinks has an opening direction that is staggered with the lateral opening of the adjacent MEMS air-cooled heat sink to reduce the mutual influence between the discharged heated air. Figure 6 As shown, each of the multiple MEMS air-cooled heat sinks 5 has a lateral opening and is arranged in a consistent opening direction to reduce the impact between the exhausted heated air g, while providing flexibility in the array design of the heat sink.

[0044] Step S2, using the control unit to apply a pulse sequence of a first drive signal and a second drive signal to the electrostatic actuator and the piezoelectric actuator respectively. In this embodiment, the first drive signal and the second drive signal are voltage signals, and based on the working principle of the actuator used, the first drive signal and the second drive signal have different amplitudes; preferably, the frequency of the second drive signal applied to the piezoelectric actuator is close to the natural frequency of the piezoelectric film, so as to increase the vibration amplitude of the diaphragm.

[0045] As shown in Figure 4, within the first time interval, the driving voltage applied to the piezoelectric actuator 33 has a negative pulse phase, the diaphragm produces a bending motion with a negative phase, the air pressure in the first fluid chamber drops to generate negative pressure, and the cooling gas is introduced into the first fluid chamber, and the cooling gas is introduced into the air chamber and the first fluid chamber through the air inlet.

[0046] As shown in Figure 5, during the second time interval, the driving voltage applied to the electrostatic actuator 13 causes the one-way microvalve assembly to close, and the driving voltage applied to the piezoelectric actuator has a positive pulse phase, and the diaphragm produces a bending motion with a positive phase. Based on the closing of the one-way microvalve assembly, the air pressure in the first fluid chamber increases to generate a positive pressure, thereby pushing a portion of the introduced cooling gas to flow from the first fluid chamber through the second fluid chamber.

[0047] Figure 7 The following is a diagram showing the relevant signal waveforms in the method of using the MEMS air-cooled heat sink. Figure 7 As shown, at step S2, at the first time interval t 1 In the case of the electrostatic actuator, the driving voltage is 0, corresponding to the opening of the one-way microvalve assembly; accordingly, the driving voltage applied to the piezoelectric actuator is -v 2 , the diaphragm produces a bending motion with a negative phase; in the second time interval t 2 The driving voltage applied to the electrostatic actuator is v 1 , corresponding to the closing of the one-way microvalve assembly; accordingly, the driving voltage applied to the piezoelectric actuator is v 2 , the diaphragm produces a bending motion with a positive phase.

[0048] In summary, a MEMS air-cooled heat sink of the present invention utilizes an actuator and a cantilever beam to construct an active one-way microvalve assembly, which cooperates with a motion execution assembly to guide the cooling gas in one direction to a fluid chamber adjacent to the hot end of the electronic device, thereby discharging the heated air to achieve a heat dissipation effect; the operating frequency of the piezoelectric film layer of the present invention is extremely high, and the ultrasonic wave generated by the vibration is inaudible. Compared with traditional air-cooled heat sinks, it has the advantages of no noise and low power consumption.

[0049] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A MEMS air-cooled heat sink, characterized in that: include: A housing, the housing comprising a base, an air inlet end and an air outlet end being provided on the housing, the air inlet end being configured to introduce cooling gas; A one-way microvalve assembly, the one-way microvalve assembly comprising a cantilever beam, a first baffle and an air chamber separated by the first baffle, the air inlet end fluid is connected to the air chamber, a through hole on the first baffle is aligned with the cantilever beam to connect the air chamber fluid to the first fluid chamber, the cantilever beam is attached with a first actuator to generate a driving force in a normal direction on the cantilever beam, so as to realize the opening or closing operation of the through hole; A motion execution assembly, the motion execution assembly comprising a stacked second partition, a diaphragm and a second actuator, the second partition being attached to the housing to separate a first fluid chamber and a second fluid chamber, an opening being formed on the second partition, at least a portion of the diaphragm being suspended above the opening to bend under the drive of the second actuator, for achieving unidirectional flow of cooling gas along a first flow path, the first flow path comprising flowing from the air chamber through the first fluid chamber and into the second fluid chamber; Wherein, the second actuator is a piezoelectric actuator, the base is removably attached to the hot end of the electronic device; and the exhaust end is configured to provide fluid communication between the second fluid chamber and the external environment.

2. The MEMS air-cooled heat sink according to claim 1, characterized in that: The shell includes a top cover, and the cantilever beam includes a fixed part and a movable part, the fixed part is anchored on the top cover, and the movable part is suspended above the first partition and directly contacts the first actuator; wherein the first actuator includes one of an electrostatic actuator and a piezoelectric actuator.

3. The MEMS air-cooled heat sink according to claim 1, characterized in that: The first actuator and the cantilever beam constitute an electrostatic ultrasonic transducer, which includes a top electrode attached to the cantilever beam and a bottom electrode mounted near the through hole. When a driving signal is applied between the top electrode and the bottom electrode, the movable part of the cantilever beam is caused to reciprocate around its fixed part toward or away from the first partition, thereby opening or closing the through hole.

4. The MEMS air-cooled heat sink according to claim 1, characterized in that: The second partition plate includes a vent hole offset relative to the through hole for providing fluid communication between the first fluid chamber and the second fluid chamber.

5. The MEMS air-cooled heat sink according to claim 3, characterized in that: The device also includes a control unit, which is electrically connected to the first actuator and is used to provide a driving signal indicating the opening or closing of the one-way microvalve assembly.

6. The MEMS air-cooled heat sink according to claim 5, characterized in that: The motion execution component is configured as a piezoelectric micromechanical ultrasonic transducer, and the control unit is electrically connected to the piezoelectric micromechanical ultrasonic transducer to draw the cooling gas into the first fluid chamber when the diaphragm moves to a negative phase; or, to push the cooling gas to flow from the first fluid chamber into the second fluid chamber when the diaphragm moves to a positive phase.

7. The MEMS air-cooled heat sink according to claim 1, characterized in that: The exhaust port is configured as an opening located at a side wall of the second fluid chamber, for providing fluid communication between the second fluid chamber and an external environment.

8. The MEMS air-cooled heat sink according to claim 2, characterized in that: The air inlet end and the through hole are arranged on opposite sides of the air chamber; wherein the air inlet end is arranged as a plurality of air inlet holes penetrating the top cover.

9. A method for using a MEMS air-cooled heat sink, characterized in that: The following steps are involved: Attaching the MEMS air-cooled heat sink as claimed in claim 1 to the hot end of the electronic device; The control unit applies a pulse sequence of a first driving signal and a second driving signal to the first actuator and the second actuator respectively, so that the cantilever beam and the diaphragm vibrate back and forth, wherein each pulse cycle includes a first time interval and a second time interval: wherein, In the first time interval, by making the second driving signal applied to the second actuator have a negative pulse phase, the cooling gas is introduced through the air inlet end while the one-way microvalve component is kept open; During the second time interval, a first drive signal is applied to the first actuator, causing the microvalve assembly to close to air-tightly isolate the air chamber from the first fluid chamber, and at the same time, a second drive signal applied to the second actuator has a positive pulse phase, causing a portion of the introduced cooling gas to flow from the first fluid chamber through the second fluid chamber and be discharged to the external environment.

10. The method of use according to claim 9, characterized in that: A plurality of MEMS air-cooled heat sinks are arranged in an array at the hot end of an electronic device, each of the plurality of MEMS air-cooled heat sinks having a lateral opening, and the plurality of MEMS air-cooled heat sinks are arranged so that the lateral opening of any MEMS air-cooled heat sink has an opening orientation staggered from the lateral opening of an adjacent MEMS air-cooled heat sink.

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