Miniature heat dissipation device air outlet structure and miniature heat dissipation device

Abstract

The invention relates to the technical field of piezoelectric fans, in particular to an air outlet structure of a miniature heat dissipation device and the miniature heat dissipation device.The air outlet structure comprises an air outlet plate provided with an air outlet flow channel, the air outlet flow channel is arranged in a roundabout mode, and the air outlet flow channel sequentially comprises a hot air area communicated with an air outlet of the heat dissipation device, and airflow subjected to heat exchange flows into the hot air area; one end of the first area communicates with the end of the hot air area, and the first area is arranged in the direction away from the hot air area and then close to the hot air area and used for changing the airflow direction and forming airflow accumulation; one end of the second area is communicated with the other end of the first area, and the other end is communicated with the outside; wherein the second area is provided with a part adjacent to the hot air area, the part forms low pressure after being heated by the hot air area, and the low pressure and high-pressure airflow formed in the first area form a pressure intensity gradient, so that the airflow in the first area flows to the second area in an accelerated mode and then is exhausted to the outside. By means of the arrangement, airflow flows out in an accelerated mode, and the heat dissipation efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric fans, and in particular, to an air outlet structure of a micro heat dissipation device and a micro heat dissipation device. Background Art

[0002] A piezoelectric fan, also known as a micro heat dissipation device, utilizes the inverse piezoelectric effect of piezoelectric materials. When an alternating voltage is applied to the piezoelectric material, it can generate reciprocating deformation, which can drive the blades to vibrate rapidly, pushing the air to form an air flow. It has the advantages of small size, low power consumption, and low noise, and is widely used in the heat dissipation of electronic devices, micro ventilation systems, and other fields.

[0003] Currently, most piezoelectric fans still have problems such as low air volume. In the prior art, increasing the frequency or the number of fan blades is mostly used to increase the air volume. However, the inventor has found that most of the existing piezoelectric fans have problems such as unsmooth flow channels or backflow phenomena, which reduces the heat dissipation efficiency of the piezoelectric fans. Summary of the Invention

[0004] In view of at least one of the above technical problems, the present invention provides an air outlet structure of a micro heat dissipation device and a micro heat dissipation device, and improves the output efficiency of the air flow by improving the air outlet structure.

[0005] According to a first aspect of the present invention, there is provided an air outlet structure of a micro heat dissipation device, including: An air outlet plate, on which an air outlet flow channel is provided. The air outlet flow channel is arranged in a circuitous manner and sequentially includes: A hot air zone, which is communicated with the air outlet of the heat dissipation device, and the air flow after heat exchange flows into the hot air zone; A first region, one end of which is communicated with the end of the hot air zone. The first region is arranged in a direction that first moves away from and then approaches the hot air zone, so as to change the air flow direction and form an air flow accumulation; A second region, one end of which is communicated with the other end of the first region, and the other end is communicated with the outside; Wherein, the second region has a part adjacent to the hot air zone. This part is heated by the hot air zone to form a low pressure, which constitutes a pressure gradient with the high-pressure air flow accumulated in the first region, so that the air flow in the first region accelerates and flows into the second region and then is discharged to the outside.

[0006] In some embodiments of the present invention, the hot air zone is a groove structure. The second region includes a heated section communicated with the first region and an air outlet section communicated with the outside. The heated section is adjacent to the hot air zone.

[0007] In some embodiments of the present invention, a third region connected to the second region is further included, one end of the third region is connected to the distal end of the heated section, and the other end of the third region is connected to the proximal end of the air outlet section, and the third region is used to change the direction of the air flow so that a pressure gradient is formed between the third region and the air outlet section.

[0008] In some embodiments of the present invention, the first region and the third region each include two direction-changing segments disposed in parallel and spaced apart, and a connecting segment connected to the same end of the two direction-changing segments; One of the two deflection sections of the first region is connected to the end of the hot air zone, and the other is connected to the head end of the heated section; One of the two direction-changing sections in the third area is connected to the end of the heating section, and the other is connected to the head end of the air outlet section.

[0009] In some embodiments of the present invention, the first region or the third region has rounded corners at its corners.

[0010] In some embodiments of the present invention, at least one partition bar is further provided in the air outlet flow channel to divide the air outlet flow channel into at least two branch flow channels.

[0011] In some embodiments of the present invention, the heating section is arranged in parallel with the hot air zone.

[0012] In some embodiments of the present invention, the area between the heated section and the wall surface of the hot air zone constitutes a heat conducting rib, and the heat conducting rib is deformed toward the heated section or the hot air zone to increase the heat conducting area.

[0013] In some embodiments of the present invention, the thermal conductive ribs are in an arc shape, a wave shape, a sawtooth shape, or a continuous triangular structure.

[0014] According to a second aspect of the present invention, there is also provided a micro heat dissipation device, comprising: The air outlet plate as described in any one of the first aspects; An air outlet layer is connected to the air outlet plate, and the air outlet layer has an air outlet corresponding to the hot air area of ​​the air outlet plate; A lower supporting layer is closely connected to a side of the air outlet layer facing away from the air outlet plate; A power layer, the power layer having fan blades and piezoelectric ceramics attached to the fan blades for driving the fan blades to vibrate; An upper supporting layer is closely connected to a side of the power layer facing away from the lower supporting layer, and both the upper supporting layer and the lower supporting layer have cavities for the blades to vibrate; The intake layer is continuously attached to the side of the upper support layer facing away from the power layer, and there are intake holes on the intake layer or the upper support layer.

[0015] The beneficial effects of the present invention are as follows: Through the heating of the second area by the hot air area on the air outlet plate in the present invention, the second area forms a low-pressure area. And through the turning setting of the first area connected to the hot air area, the air pressure in the first area increases, and then a pressure gradient difference is formed between the first area and the second area. This pressure gradient difference will cause the air flow in the first area to quickly flow to the second area and then be discharged. Through the setting of this structure, compared with the prior art, it can not only improve the output efficiency of the air flow, improve the heat dissipation efficiency, but also reduce the use of materials and reduce the overall weight of the heat dissipation device. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a schematic structural diagram of the air outlet structure of the micro heat dissipation device in the embodiment of the present invention; Figure 2 It is a schematic structural diagram of the air outlet plate in the embodiment of the present invention; Figure 3 It is a schematic diagram of the principle of air flow acceleration in the air outlet flow channel in the embodiment of the present invention; Figure 4 It is a schematic structural diagram of another air outlet plate in the embodiment of the present invention; Figure 5 It is a schematic structural diagram of the first area and the third area in the embodiment of the present invention; Figure 6 It is a schematic structural diagram of a deformed form of the air outlet plate in the embodiment of the present invention; Figure 7 It is a schematic structural diagram of a heat conduction rib in the air outlet plate in the embodiment of the present invention; Figure 8 It is a schematic structural diagram of a deformed form of the heat conduction rib in the air outlet plate in the embodiment of the present invention; Figure 9 It is a schematic structural diagram of another deformed form of the heat conduction rib in the air outlet plate in the embodiment of the present invention; Figure 10 It is a schematic exploded view of the micro heat dissipation structure in the embodiment of the present invention.

[0018] Explanation of the accompanying drawings: 1. air outlet plate; 11. air outlet channel; 12. partition bar; 111. hot air zone; 112. first zone; 112a. turning section; 112b. connecting section; 112c. rounded corner; 113. second zone; 113a. heating section; 113b. air outlet section; 114. third zone; 115. heat conducting rib; 2. air outlet layer; 21. air outlet; 3. lower supporting layer; 31. cavity; 4. power layer; 41. fan blade; 42. piezoelectric ceramic; 5. upper supporting layer; 51. air inlet; 6. air inlet layer. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0022] like Figures 1 to 9 The air outlet structure of the micro heat sink shown in the figure includes an air outlet plate 1. For details, please refer to Figure 1 and Figure 2 In the embodiment of the present invention, the air outlet plate 1 has an air outlet channel 11, and the air outlet channel 11 is arranged in a circuitous manner. The circuitous arrangement here refers to a structure in which the air outlet channel 11 has at least one flow direction change. Compared with the direct air outlet structure, the circuitous arrangement can reduce the backflow phenomenon caused by the short flow channel. In the embodiment of the present invention, Figure 2As shown in the figure, the air outlet channel 11 successively includes a hot air zone 111, a first zone 112, and a second zone 113. Specifically, the hot air zone 111 is communicated with the air outlet 21 of the heat dissipation device, and the air flow after heat exchange flows into the hot air zone 111. It should be noted here that the air outlet 21 of the heat dissipation device refers to the port through which the air flow formed by the reciprocating vibration of the piezoelectric fan through the fan blades 41 blows out. The air flow after heat exchange can be heat-exchanged before passing through the fan blades 41 or in the hot air zone 111 of the air outlet plate 1. One end of the first zone 112 is communicated with the end of the hot air zone 111. As Figure 2 shown in the figure, the first zone 112 is arranged in a direction that first moves away from and then approaches the hot air zone 111 to change the air flow direction and form an air flow accumulation. It should be noted here that the purpose of forming the air flow accumulation is to form a relative high pressure. There are various structural forms for changing the air flow direction, such as achieving it through multiple changes in the flow direction, and those skilled in the art can select according to actual needs. One end of the second zone 113 is communicated with the other end of the first zone 112, and the other end is communicated with the outside. In the embodiment of the present invention, the second zone 113 has a part adjacent to the hot air zone 111. After this part is heated by the hot air zone 111, a low pressure is formed, which constitutes a pressure gradient with the high-pressure air flow accumulated in the first zone 112, so that the air flow in the first zone 112 accelerates and flows into the second zone 113 and then is discharged to the outside.

[0023] As Figure 3 shown in the figure, in the embodiment of the present invention, since the hot air zone 111 is the area where the hot air first enters, after the second zone 113 parallel and adjacent to it is irradiated by the heat radiation of the hot air zone 111, as the temperature in the second zone 113 rises, the density of the hot air in the second zone 113 decreases to form a low-pressure zone. And in the first zone 112, due to the design of its turning structure, the air flow blown from the hot air zone 111 accumulates or stays in the first zone 112, thereby increasing the pressure in the first zone 112 to form a high-pressure zone. Since the first zone 112 is directly connected to the second zone 113, a pressure gradient difference is generated between the two. This pressure gradient difference is similar to the pressure gradient difference in the chimney structure, and it can push the gas in the first zone 112 towards the second zone 113, thereby accelerating the speed of the air flow in the first zone 112 moving towards the second zone 113.

[0024] In the above embodiments, through the heating of the second region 113 by the hot air region 111 on the air outlet plate 1, the second region 113 forms a low-pressure region. And through the steering setting of the first region 112 connected to the hot air region 111, the air pressure in the first region 112 increases. Then, a pressure gradient difference is formed between the first region 112 and the second region 113. This pressure gradient difference causes the air flow in the first region 112 to quickly flow to the second region 113 and then be discharged. Through the setting of this structure, compared with the prior art, it can not only improve the output efficiency of the air flow, enhance the heat dissipation efficiency, but also reduce the use of materials and lower the overall weight of the heat dissipation device.

[0025] Optionally, please continue to refer to Figure 2 and Figure 3 , in the embodiments of the present invention, the hot air region 111 is a groove structure, and this groove structure can be a linear type or a curved type structure. The second region 113 includes a heated section 113a communicating with the first region 112 and an air outlet section 113b communicating with the outside. The heated section 113a is disposed adjacent to the hot air region 111. As shown in Figure 3 , the heated section 113a refers to the part that coincides with the projection of the hot air region 111 in the vertical direction, and the heat conduction is realized through the wall between the hot air region 111 and the second region 113. Of course, it should also be pointed out here that in the embodiments of the present invention, the heated section 113a can be directly connected to the air outlet section 113b, or other regions can be added as described below. In the embodiments of the present invention, by setting the hot air region 111 as a linear groove structure, as shown in Figure 2 , the left end of the hot air region 111 is the starting end of the groove, which is not connected to the outside, and the right end is connected to the first region 112. Thus, the air flow entering the hot air region 111 moves from the starting end towards the first region 112 and accumulates in the first region 112 to form a high pressure.

[0026] In some embodiments of the present invention, as shown in Figure 4As shown, it further includes a third region 114 communicating with the second region 113. One end of the third region 114 communicates with the distal end of the heated section 113a, and the other end of the third region 114 communicates with the proximal end of the air outlet section 113b. The third region 114 is used to change the air flow direction and form an air flow accumulation, so as to form a pressure gradient between the third region 114 and the air outlet section 113b. Since a pressure gradient is formed between the first region 112 and the second region 113, the air flow in the first region 112 accelerates and moves towards the second region 113, and the air flow in the heated section 113a of the second region 113 gradually accumulates in the third region 114. Since the air outlet section 113b is directly connected to the outside, the pressure of the air outlet section 113b is equal to the atmospheric pressure, so that a high-pressure area is formed in the third region 114 and a low-pressure area is relatively formed in the air outlet section 113b. Under the action of this pressure gradient, the air flow will further accelerate from the third region 114 to the air outlet section 113b. Through the setting of this structure, accurate air flow diversion is achieved while avoiding air flow backflow, thereby improving the air flow output efficiency. It should also be noted here that in the embodiments of the present invention, for the sake of clearer description, based on the air flow direction, the proximal end refers to the starting end of the air flow, the distal end refers to one end where the air flow flows, and the distal end of the heated section 113a is at Figure 4 which refers to the left end, and the proximal end of the air outlet section 113b is at Figure 4 which refers to the right end.

[0027] In some embodiments of the present invention, as Figure 5 shown, both the first region 112 and the third region 114 include two turning sections 112a arranged in parallel at intervals and a connecting section 112b communicating with the same end of the two turning sections 112a; please continue to refer to Figure 4 , in the embodiments of the present invention, one of the two turning sections 112a of the first region 112 communicates with the end of the hot air region 111, and the other communicates with the head end of the heated section 113a; one of the two turning sections 112a of the third region 114 communicates with the end of the heated section 113a, and the other communicates with the head end of the air outlet section 113b. Here, the head section and the end section are also defined according to the air flow direction. The head section is the starting end of the air flow in this region, and the end section is the end where the air flow flows.

[0028] In the embodiments of the present invention, in order to make the air path flow more smoothly and reduce the turbulent flow, as Figure 5 shown, the first region 112 or the third region 114 has a rounded corner 112c at its corner position. Of course, those skilled in the art can change the size of the rounded corner 112c according to needs, or change the Figure 5 structure in it to a U-shaped structure, but the above improvements still fall within the protection scope of the present invention.

[0029] Optionally, in an embodiment of the present invention, as Figure 6 shown, at least one partition strip 12 is further provided in the air outlet flow channel 11 to divide the air outlet flow channel 11 into at least two shunt channels. By providing the partition strip 12, on the one hand, the flow channel width of the air outlet flow channel 11 becomes smaller, and the wind speed is increased. On the other hand, it also plays a role in guiding the air flow and reducing the air flow disorder. When specifically configuring, the width of the partition strip 12 can also be widened in the area from the high-pressure area to the low-pressure area according to needs, so that the flow channel becomes narrower to further increase the flow rate of the air flow.

[0030] In some embodiments of the present invention, in order to better heat the heated section 113a, as Figure 4 shown, the heated section 113a is arranged in parallel with the hot air area 111. Through the parallel arrangement, the heat in the hot air area 111 can be evenly radiated to the heated section 113a. It should be noted here that the parallel here generally refers to that the air flow directions in the heated section 113a and the hot air area 111 are close to parallel, and it does not limit that both the heated section 113a and the hot air area 111 are linear structures. Of course, as Figure 4 shown in the linear structure form also falls within the protection scope of the present invention.

[0031] In addition, in some embodiments of the present invention, in order to further improve the heating effect on the heated section 113a, as Figure 7 shown, the area between the wall surface of the heated section 113a and the hot air area 111 forms a heat conduction rib 115. The heat conduction rib 115 is deformed towards the heated section 113a or the hot air area 111 to increase the heat conduction area. Through the deformation of the heat conduction rib 115, the heating area of the hot air area 111 towards the heated section 113a can be increased, and then more heat can be transferred to the heated section 113a. In some embodiments of the present invention, the structural form of the heat conduction rib 115 has various types. It can be arc-shaped, as Figures 7 to 9 shown, the heat conduction rib 115 is a wavy, serrated or continuous triangular structure, and of course, an arc-shaped structure can also be adopted. By improving the structure of the heat conduction rib 115, the heat conduction area is increased, so that the temperature of the heated section 113a in the second area 113 is higher, and the pressure gradient difference between the heated section 113a and the first area 112 and between the third area and the air outlet section 113b is larger, and the flow rate of the air flow from the high-pressure area to the low-pressure area is faster, thereby improving the heat dissipation efficiency of the fan.

[0032] In an embodiment of the present invention, a micro heat dissipation device is further provided, including the above-mentioned air outlet plate 1, air outlet layer 2, lower support layer 3, power layer 4, upper support layer 5 and air inlet layer 6, specifically as Figure 10As shown in the figure, the air outlet channel 11 on the air outlet plate 1 is arranged facing the air outlet layer 2; the air outlet layer 2 is adhesively connected to the air outlet plate 1, and the air outlet layer 2 has an air outlet 21 corresponding to the hot air area 111 of the air outlet plate 1, and the gas flowing out from the air outlet 21 enters into the hot air area 111; the lower support layer 3 is adhesively connected to the side of the air outlet layer 2 facing away from the air outlet plate 1; the power layer 4 has fan blades 41 and piezoelectric ceramics 42 attached to the fan blades 41 for driving the fan blades 41 to vibrate; the upper support layer 5 is adhesively connected to the side of the power layer 4 facing away from the lower support layer 3, and both the upper support layer 5 and the lower support layer 3 have cavities 31 for the fan blades 41 to vibrate; through the arrangement of the vibration cavities 31 on the upper support layer 5 and the lower support layer 3, the fan blades 41 can reciprocally vibrate in the cavities 31 under the drive of the piezoelectric ceramics 42, thereby driving the flow of air; the intake layer 6 is adhesively connected to the side of the upper support layer 5 facing away from the power layer 4, and the intake layer 6 or the upper support layer 5 has intake holes 51. When specifically implementing, the intake layer 6 can be adhered to the heat source of the electronic device. After applying an excitation to the piezoelectric ceramics 42, the piezoelectric ceramics 42 vibrate up and down in the polarization direction, thereby driving the up and down swing of the fan blades 41 to generate air flow. The external air flow enters into the cavity 31 through the intake holes 51. The air flow driven by the up and down swing of the fan blades 41 flows into the air outlet layer 2 and enters into the hot air area 111 of the air outlet plate 1 through the air outlet 21, and then sequentially flows into the first area 112, the second area 113 and the third area. With the continuous input of hot air, the first area 112 is heated by the hot air area 111 to generate a pressure gradient difference. Under the action of the pressure gradient difference, a secondary speed increase is achieved in the air outlet channel 11 of the air outlet plate 1. Through the above arrangement, the output efficiency of the piezoelectric fan is effectively increased, and thus the heat dissipation efficiency is improved.

[0033] Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A micro heat dissipation device air outlet structure, characterized in that: include: The air outlet plate has an air outlet channel, the air outlet channel is arranged in a circuitous manner, and the air outlet channel sequentially includes: A hot air zone, the hot air zone is connected to the air outlet of the heat dissipation device, and the airflow after heat exchange flows into the hot air zone; A first region, one end of which is connected to the end of the hot air zone, and the first region is arranged in a direction first away from and then close to the hot air zone to change the airflow direction and form airflow accumulation; A second region, one end of which is connected to the other end of the first region, and the other end of which is connected to the outside world; Among them, the second area has a part adjacent to the hot wind area, which forms low pressure after being heated by the hot wind area, and forms a pressure gradient with the high-pressure airflow formed in the first area, so that the airflow in the first area is accelerated to flow to the second area and then discharged to the outside.

2. The air outlet structure of the micro heat sink according to claim 1, characterized in that: The hot air zone is a groove structure, the second area includes a heating section connected to the first area and an air outlet section connected to the outside, and the heating section is arranged adjacent to the hot air zone.

3. The air outlet structure of the micro heat sink according to claim 2, characterized in that: It also includes a third area connected to the second area, one end of the third area is connected to the distal end of the heated section, and the other end of the third area is connected to the proximal end of the air outlet section, and the third area is used to change the air flow direction so that a pressure gradient is formed between the third area and the air outlet section.

4. The air outlet structure of the micro heat sink according to claim 3, characterized in that: The first area and the third area each include two direction-changing sections arranged in parallel and spaced apart from each other, and a connecting section connected to the same end of the two direction-changing sections; One of the two deflection sections of the first region is connected to the end of the hot air zone, and the other is connected to the head end of the heated section; One of the two direction-changing sections in the third area is connected to the end of the heating section, and the other is connected to the head end of the air outlet section.

5. The air outlet structure of the micro heat sink according to claim 4, characterized in that: The first region or the third region has rounded corners at its corner positions.

6. The air outlet structure of the micro heat sink according to claim 1 or 3, characterized in that: At least one partition bar is also arranged in the air outlet flow channel to divide the air outlet flow channel into at least two branch flow channels.

7. The air outlet structure of the micro heat sink according to claim 2 or 3, characterized in that: The heating section is arranged in parallel with the hot air zone.

8. The air outlet structure of the micro heat sink according to claim 7, characterized in that: The area between the heated section and the wall surface of the hot wind zone constitutes a heat-conducting rib, and the heat-conducting rib is deformed toward the heated section and the hot wind zone to increase the heat-conducting area.

9. The air outlet structure of the micro heat sink according to claim 8, characterized in that: The heat conducting ribs are in arc, wave, sawtooth or continuous triangular shapes.

10. A micro heat sink, characterized in that: include: The air outlet plate according to any one of claims 1 to 9; An air outlet layer is connected to the air outlet plate, and the air outlet layer has an air outlet corresponding to the hot air area of ​​the air outlet plate; A lower supporting layer is closely connected to a side of the air outlet layer facing away from the air outlet plate; A power layer, the power layer having fan blades and piezoelectric ceramics attached to the fan blades for driving the fan blades to vibrate; An upper supporting layer is closely connected to a side of the power layer facing away from the lower supporting layer, and both the upper supporting layer and the lower supporting layer have cavities for the blades to vibrate; The air intake layer is in continuous contact with the side of the upper supporting layer facing away from the power layer, and the air intake layer or the upper supporting layer is provided with air intake holes.

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