Heat dissipation device and electronic equipment

Abstract

The invention provides a heat dissipation device and electronic equipment, a first cover body and a second cover body of the heat dissipation device are oppositely arranged and are connected to form an airtight cavity, and the airtight cavity is used for accommodating a cooling working medium; the working medium has a first state and a second state, heat absorption of the working medium in the first state is changed from the first state to the second state, and cooling of the working medium in the second state is changed from the second state to the first state; the first working medium transport layer is arranged on the first inner surface, opposite to the second cover body, of the first cover body; the second working medium transport layer is arranged on the second inner surface, opposite to the first cover body, of the second cover body; wherein the working medium which is changed from the second state to the first state when encountering cold at the first cover body comprises a first part and a second part, the first part flows back to the evaporation end where the heat source of the second cover body is located through the first working medium transport layer, and the second part flows back to the evaporation end where the heat source of the second cover body is located through the second working medium transport layer.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation of electronic devices, and particularly relates to a heat dissipation device and an electronic device. Background Art

[0002] With the increasing demand for improving the heat dissipation capacity of electronic devices, restricted by the requirement of the thickness of the electronic device body, the thickness of the heat dissipation device is also limited, and the method of increasing the heat dissipation performance by increasing the thickness of the heat dissipation device is restricted. How to improve the heat dissipation performance of the bulk device without increasing the thickness of the heat dissipation device is the technical problem to be solved by the present application. Summary of the Invention

[0003] The purpose of the embodiments of the present application is to provide a bulk device and an electronic device.

[0004] The embodiments of the present application adopt the following technical solutions: A heat dissipation device includes: a first cover body and a second cover body;

[0005] The first cover body and the second cover body are arranged opposite to each other and are connected to form an airtight cavity for accommodating a cooling working fluid; the working fluid has a first state and a second state, wherein the working fluid in the first state absorbs heat and changes from the first state to the second state, and the working fluid in the second state cools and changes from the second state to the first state;

[0006] A first working fluid transport layer is disposed on a first inner surface of the first cover body opposite to the second cover body;

[0007] A second working fluid transport layer is disposed on a second inner surface of the second cover body opposite to the first cover body; wherein, the working fluid that changes from the second state to the first state when encountering cold at the first cover body includes a first part and a second part, the first part flows back to the evaporation end where the heat source of the second cover body is located through the first working fluid transport layer, and the second part flows back to the evaporation end where the heat source of the second cover body is located through the second working fluid transport layer.

[0008] In some embodiments, it further includes a third working fluid transport layer disposed between the first inner surface and the second inner surface; the second part flows back to the evaporation end where the heat source of the second cover body is located through the third working fluid transport layer and the second working fluid transport layer.

[0009] In some embodiments, the first working fluid transport layer is a first groove capillary structure, and the first groove capillary structure includes a plurality of first grooves, and the plurality of first grooves are divergently arranged relative to the evaporation end, so that the first part can flow back to the evaporation end where the heat source of the second cover body is located along the plurality of first grooves in multiple directions.

[0010] In some embodiments, the plurality of first grooves are divergently arranged relative to the evaporation end, including that the first ends of the plurality of first grooves are located at positions corresponding to the heat source on the first inner surface of the first cover body, and the second ends of the plurality of first grooves extend to the edge positions of the first inner surface of the first cover body.

[0011] In some embodiments, columns extending into the airtight cavity are provided on the first inner surface of the first cover body, the columns abut against the second inner surface of the second cover body, and the orthographic projection of the columns on the first inner surface of the first cover body avoids the plurality of first grooves.

[0012] In some embodiments, the second working fluid transport layer includes a second groove capillary structure, the second grooves are divergently arranged relative to the heat source, and the density of the second grooves is greater than the density of the first grooves.

[0013] In some embodiments, the second working fluid transport layer includes a plurality of third groove capillary structures;

[0014] The plurality of third grooves are coaxially arranged around the position corresponding to the heat source on the second inner surface of the second cover body respectively; the plurality of third grooves divide the second grooves into multiple segments.

[0015] In some embodiments, the groove width of one end of the second groove segment close to the evaporation end is greater than the groove width of the end far from the evaporation end.

[0016] In some embodiments, the second working fluid transport layer includes a fourth groove capillary structure;

[0017] The fourth groove capillary structure includes a plurality of fourth grooves, the plurality of fourth grooves are arranged in parallel, and at least part of the plurality of fourth grooves passes through the position corresponding to the heat source on the second inner surface of the second cover body.

[0018] The embodiment of the present application further provides an electronic device, including a heat dissipation device and a heat source as described in any one of the above embodiments, the heat source is arranged at the evaporation end of the second cover body of the heat dissipation device, the first cover body and the second cover body of the heat dissipation device are arranged oppositely and connected to form an airtight cavity, and the airtight cavity is used to accommodate a cooling working fluid; the working fluid has a first state and a second state, wherein the working fluid in the first state absorbs heat and changes from the first state to the second state, and the working fluid in the second state cools and changes from the second state to the first state;

[0019] The first working fluid transport layer of the heat dissipation device is arranged on the first inner surface of the first cover body opposite to the second cover body;

[0020] The second working fluid transport layer of the heat dissipation device is arranged on the second inner surface of the second cover body opposite to the first cover body;

[0021] Among them, the working fluid that changes from the second state to the first state when encountering cold at the first cover body includes a first part and a second part. The first part flows back to the evaporation end where the heat source of the second cover body is located through the first working fluid transport layer, and the second part flows back to the evaporation end where the heat source of the second cover body is located through the second working fluid transport layer. Description of the Drawings

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a schematic cross-sectional structure diagram of the heat dissipation device of the present application (the dashed square in the figure is the evaporation end corresponding to the heat source of the second cover body);

[0024] Figure 2 It is another schematic cross-sectional structure diagram inside the heat dissipation device of the present application;

[0025] Figure 3 It is a schematic diagram of the arrangement manner of the first groove capillary structure and the column on the first inner surface of the first cover body of the present application;

[0026] Figure 4 It is a schematic structure diagram when the second working fluid transport layer of the present application includes a plurality of third groove capillary structures (the dashed square in the figure is the evaporation end of the heat source of the second cover body);

[0027] Figure 5 For Figure 4 The partial enlarged view of A in

[0028] Figure 6 It is a schematic structure diagram when the second working fluid transport layer of the present application includes a fourth groove capillary structure.

[0029] Reference numerals: 1. First cover body; 2. Second cover body; 3. Airtight cavity; 4. First working fluid transport layer; 5. Second working fluid transport layer; 6. Heat source; 7. Third working fluid transport layer; 8. First groove capillary structure; 9. Column; 10. Second groove capillary structure; 11. Third groove capillary structure; 12. Fourth groove capillary structure. Detailed Embodiments

[0030] The various solutions and features of the present application are described herein with reference to the drawings.

[0031] It should be understood that various modifications can be made to the embodiments applied herein. Therefore, the above description should not be regarded as limiting, but only as an example of the embodiments. Those skilled in the art will think of other modifications within the scope and spirit of the present application.

[0032] The accompanying drawings, which are included in and constitute a part of this specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0033] These and other features of the present application will become apparent from the following description of the preferred forms of the embodiments given by way of non-limiting example with reference to the accompanying drawings.

[0034] It should also be understood that although the present application has been described with reference to some specific examples, those skilled in the art can definitely implement many other equivalent forms of the present application.

[0035] When combined with the accompanying drawings, the above and other aspects, features, and advantages of the present application will become more apparent in view of the following detailed description.

[0036] Specific embodiments of the present application will be described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments applied are merely examples of the present application and can be implemented in various ways. Well-known and / or repetitive functions and structures are not described in detail to avoid obscuring the present application with unnecessary or redundant details. Therefore, the specific structural and functional details applied herein are not intended to be limiting, but merely serve as a basis for the claims and a representative basis for teaching those skilled in the art to use the present application in substantially any suitable detailed structure in a variety of ways.

[0037] This specification may use the phrases "in one embodiment", "in another embodiment", "in yet another embodiment", or "in other embodiments", each of which may refer to one or more of the same or different embodiments according to the present application.

[0038] To solve the problems in the background art, an embodiment of the present application provides a heat dissipation device, which can be applied to an electronic device.

[0039] Combined with Figure 1, the heat dissipation device includes a first cover 1 and a second cover 2. The first cover 1 and the second cover 2 are arranged opposite to each other and connected to form an airtight cavity 3. In one embodiment, the thickness of the airtight cavity 3 is greater than 0.15 mm. In another embodiment, the thickness of the airtight cavity 3 can also be set to be greater than 0.12 mm, and specifically, it can be set according to actual production needs. For example, the first cover 1 and the second cover 2 can be connected to form the airtight cavity 3 by means of welding, sealant, etc. The airtight cavity 3 is used to accommodate a cooling working fluid. In the application scenario where the heat dissipation device is applied to an electronic device, the cooling working fluid can be, but is not limited to, pure water, oil, deionized water, organic working fluids such as methanol, ethanol, n-pentane, propylene glycol, a liquid with added refrigerant, etc. The working fluid has a first state and a second state. Among them, the working fluid in the first state absorbs heat and changes from the first state to the second state, and the working fluid in the second state cools and changes from the second state to the first state.

[0040] For example, taking pure water as the cooling working fluid, the airtight cavity 3 can be evacuated to lower the boiling point of water, so that the water in the airtight cavity 3 can change its state faster after receiving the heat released by the heat source 6. For example, the temperature of the water in the airtight cavity 3 can be controlled at about 35°C to 60°C, so that the water in the airtight cavity 3 can change from the first state to the second state after absorbing a certain amount of heat. Combined Figure 2 , for example, the first state can be liquid and the second state can be gaseous. The water in the second state can flow outward and diffuse through the airtight cavity 3 from the position where heat is generated. The water in the second state cools after releasing heat to achieve heat dissipation. After the water in the second state cools, it can change from the second state to the first state again, that is, from gaseous to liquid.

[0041] The heat dissipation device further includes a first working fluid transport layer 4, and the first working fluid transport layer 4 is arranged on the first inner surface of the first cover 1 opposite to the second cover 2. The heat dissipation device further includes a second working fluid transport layer 5, and the second working fluid transport layer 5 is arranged on the second inner surface of the second cover 2 opposite to the first cover 1. That is, the airtight cavity 3 has at least two relatively arranged inner wall surfaces, and the two relatively arranged inner wall surfaces are respectively the first inner surface arranged on the first cover 1 and the second inner surface arranged on the second cover 2.

[0042] Among them, the working fluid that changes from the second state to the first state when encountering cold at the first cover 1 includes a first part and a second part. The first part flows back to the evaporation end where the heat source 6 is located on the second cover 2 through the first working fluid transport layer 4. That is, the first working fluid transport layer 4 can realize the direct reflux of the liquid on the condensation surface, greatly improving the efficiency of the vapor-liquid cycle.

[0043] The second part flows back to the evaporation end where the heat source 6 of the second cover body 2 is located through the second working medium transport layer 5. For example, continuing with the above embodiment, the working medium in the first state (liquid state) absorbs heat and evaporates to transform into the second state (vapor state). The working medium in the second state will flow away from the evaporation end where the heat source 6 is located in the evaporation end position. As the distance from the evaporation end where the heat source 6 is located increases, the heat of the working medium in the second state is continuously released and continuously cooled and then transformed back into the first state.

[0044] Of course, it should be noted here that when the working medium in the first state absorbs heat and transforms into the second state, not all of the working medium in the first state in the airtight cavity 3 transforms into the second state. The working medium in the evaporation end where the heat source 6 of the second cover body 2 is located and near the evaporation end where the heat source 6 is located will transform into the second state faster. In addition, when the working medium in the first state absorbs heat and transforms into the second state, the working medium in the second state may be precooled in the first cover body 1 and transformed from the second state into the first state; it may also transform from the second state into the first state in the airtight cavity 3 when flowing away from the evaporation end where the heat source 6 is located in the airtight cavity 3, or it may transform from the second state into the first state in the second cover body 2 when flowing away from the evaporation end where the heat source 6 is located in the airtight cavity 3. In short, the state of the working medium in the airtight cavity 3 is a relatively complex state, and it does not absolutely exist in a certain position in the first state or the second state.

[0045] The working medium that is cooled at the first cover body 1 and transformed from the second state into the first state includes a first part and a second part. Among them, the first part can flow back to the evaporation end where the heat source 6 of the second cover body 2 is located through the first working medium transport layer 4. The first part can only flow in the first working medium transport layer 4, or it may drip onto the second cover body 2 from the first working medium transport layer 4. The second part can flow back to the evaporation end where the heat source 6 of the second cover body 2 is located through the second working medium transport layer 5. For example, at the condensation end far from the evaporation end where the heat source 6 of the second cover body 2 is located, the amount of the working medium transformed into the first state is relatively large. The working medium in the first state will drip onto the second working medium transport layer 5 on the second cover body 2, and then flow back to the evaporation end where the heat source 6 of the second cover body 2 is located through the second working medium transport layer 5. In this way, the state transformation of the working medium can be realized, and the working medium can realize the multi-path rapid circulation flow of the working medium through the airtight cavity 3, the first working medium transport layer 4, and the second working medium transport layer 5, thereby improving the heat dissipation efficiency of the heat dissipation device without increasing the thickness of the heat dissipation device. Furthermore, a substantial increase in the overall transient and steady-state heat dissipation power of the heat dissipation device is achieved. The transient power refers to the heat dissipation power that the system can bear when the heating time of the heat source is relatively short. At this time, the system has not reached the thermal equilibrium state. For example, within 3 minutes can be considered as transient, and more than 10 minutes can be considered as steady state, and the system has basically reached the thermal equilibrium state; usually the transient power will be greater, and the increase amplitude of the transient power is also greater when the heat dissipation performance is improved.

[0046] In some embodiments, the heat dissipation device further includes a third working fluid transport layer 7, which is disposed between the first inner surface and the second inner surface. The second part flows back to the evaporation end where the heat source 6 of the second cover 2 is located through the third working fluid transport layer 7 and the second working fluid transport layer 5.

[0047] For example, the third working fluid transport layer 7 can be laid on the second inner surface of the second cover 2, so that the heat dissipation device can form a three-layer three-dimensional working fluid transport structure of the first working fluid transport layer 4, the third working fluid transport layer 7, and the second working fluid transport layer 5. Since the working fluid has a certain weight, a large part of the working fluid cooled at the condensation end will settle towards the second cover 2 under the action of gravity, and the amount of the working fluid in the first state (the second part of the working fluid) after settlement is relatively large. The third working fluid transport layer 7 and the second working fluid transport layer 5 are used to transport the cooled working fluid in the first state back, which speeds up the liquid return speed, improves the return efficiency of the cooled working fluid in the first state, so that the working fluid in the first state can return to the evaporation end where the heat source 6 of the second cover 2 is located faster. Furthermore, the working fluid at the evaporation end corresponding to the position of the heat source 6 of the second cover 2 can absorb heat again and turn into the working fluid in the second state, that is, through the three-dimensional return path of the three-layer working fluid transport layer, the vapor-liquid circulation efficiency is greatly improved, thereby improving the overall heat dissipation efficiency of the heat dissipation device.

[0048] The third working fluid transport layer 7 can be, but is not limited to, a metal mesh layer, and the metal mesh layer is one layer or multiple layers stacked. The metal mesh layer can be, but is not limited to, a woven copper mesh or a stainless steel mesh, etc. The metal mesh layer also has capillary adsorption ability, and moreover, the metal mesh layer also has a certain adsorption and penetration effect on the working fluid. The third working fluid transport layer 7 and the second working fluid transport channel cooperate to transport the working fluid in the first state (the second part) cooled at the condensation end to the evaporation end. Specifically, the third working fluid layer is laid on the second inner surface of the second cover 2, and the second working fluid transport layer 5 and the third working fluid transport layer 7 can be connected. Therefore, the second working fluid transport layer 5 and the third working fluid transport layer 7 can form a mutually connected working fluid transport layer. Compared with a single-layer working fluid transport layer, the capillary force and permeability of this working fluid transport layer are improved. The higher the permeability, the greater the amount of transported working fluid, and the amount of heat transported can be increased. In addition, the composite of the second working fluid transport layer 5 and the metal mesh layer on the second inner surface of the second cover 2 reduces the global viscous resistance of the working fluid, strengthens the critical heat flux density, greatly enhances the capillary force, strengthens the critical heat flux density, improves the vapor-liquid circulation heat dissipation efficiency, and further improves the heat dissipation power of the heat dissipation device.

[0049] The embodiment of the present application has no influence on the overall size of the heat dissipation device, and improves the heat dissipation effect of the heat dissipation device without increasing the area, thickness, and weight of the heat dissipation device.

[0050] In some embodiments, the first working fluid transport layer 4 is a first groove capillary structure 8. The first groove capillary structure 8 refers to a groove structure with capillary force. Through the first groove capillary structure 8, the working fluid in the first part can be quickly refluxed to the evaporation end where the heat source 6 of the second cover 2 is located under the action of the capillary force of the first groove capillary structure 8.

[0051] Combined with Figure 3 , the first groove capillary structure 8 includes a plurality of first grooves. The plurality of first grooves are arranged in a divergent shape relative to the evaporation end, so that the first part can flow back to the evaporation end where the heat source 6 of the second cover 2 is located along the plurality of first grooves in multiple directions, thereby improving the efficiency of the first part of the working fluid reflux.

[0052] The number of the first grooves can be set according to the position of the evaporation end where the heat source 6 of the second cover 2 is located, the area and shape of the first cover 1, etc. Taking Figure 3 the first cover 1 of the heat dissipation device shown as a rectangle as an example, the position of the positive projection of the evaporation end of the heat source 6 of the second cover 2 on the first cover 1 is located on the left side of the first cover 1 and at a position with a relatively equal front-back distance relative to the first cover 1. The plurality of first grooves can be symmetrically arranged front and back, so that the first part of the working fluid can flow back to the evaporation end more evenly.

[0053] Of course, it can be understood that the arrangement manner of the plurality of first grooves can also be other forms. Only this is taken as an example and does not constitute a limitation on the protection scope of the claims.

[0054] In addition, this application Figure 3 takes the design manner of the first groove as a straight groove as an example for illustration. Of course, it can be understood that in addition to the design manner of the straight groove, the first groove can also be in other design manners such as a curve or a bent line, which will not be listed one by one here.

[0055] The groove width of each first groove is very small. For example, the groove width is about 50 um, which has little impact on the strength of the first cover 1, or the impact of the arrangement of the first grooves on the strength of the first cover 1 can be ignored.

[0056] In some embodiments, the plurality of first grooves are arranged in a divergent shape relative to the evaporation end, including that the first ends of the plurality of first grooves are located at the positions corresponding to the heat source 6 on the first inner surface of the first cover 1, and the second ends of the plurality of first grooves extend to the edge positions of the first inner surface of the first cover 1.

[0057] Continuing with Figure 3For example, each first groove may include two ends, namely a first end and a second end. Among them, the first end of each first groove is located at a position on the first inner surface of the first cover body 1 corresponding to the heat source 6. The first ends of each first groove may be connected to each other or not. The second end of each first groove extends in a direction away from the heat source 6 and extends to the edge position of the first inner surface of the first cover body 1. For example, continuing to take the first cover body 1 as a rectangle, the second end of the first groove may extend to the corner position of the first inner surface of the first cover body 1, so that the first part of the working fluid at the corner position of the first surface of the first cover body 1 can flow back to the evaporation end where the heat source 6 of the second cover body 2 is located, avoiding the cooled working fluid from accumulating at the corner position of the first inner surface of the first cover body 1 and being unable to form a vapor-liquid cycle.

[0058] Combined again Figure 3 , because the position of the heat source 6 on the first inner surface of a first cover body 1 is close to the left edge of the first inner surface of the first cover body 1 shown in the figure, the working fluid in the corresponding area may not be cooled from the second state to the first state, or the amount of the working fluid in the corresponding area changing from the second state to the first state is very small, and there is no need to circulate and flow back to the evaporation end position, or the working fluid changing to the first state quickly absorbs the heat released by the heat source 6 very close to this area and then changes to the second state. Therefore, no first groove may be provided at the position close to the left edge of the first inner surface of the first cover body 1 shown in the figure. Of course, it can be understood that a first groove may also be provided in this area according to actual needs.

[0059] In some embodiments, columns 9 extending into the airtight cavity 3 are provided on the first inner surface of the first cover body 1, and the columns 9 abut against the second inner surface of the second cover body 2. Combined Figure 1 , the columns 9 on the first inner surface of the first cover body 1 abut against the inner surface of the second cover body 2 to form a supporting effect, preventing the first cover body 1 and / or the second cover body 2 from being deformed by force and resulting in the airtightness of the airtight cavity 3 not being guaranteed, and also avoiding the first cover body 1 and / or the second cover body 2 being deformed by force and causing the working fluid to not flow smoothly at the corresponding deformed positions of the first working fluid transport layer 4 and / or the second working fluid transport layer 5 and the airtight cavity 3, thus affecting the heat exchange effect of the heat exchange device.

[0060] Combined again Figure 3 , the orthographic projection of the column 9 on the first inner surface of the first cover body 1 avoids a plurality of first grooves, that is, the setting of the column 9 cannot affect the setting of the first grooves, and there is no structural interference between the first grooves and the column 9, so as to ensure the smoothness of the first part of the working fluid flowing back in the first grooves as much as possible, thereby ensuring the vapor-liquid reflux efficiency and the heat dissipation efficiency of the heat dissipation device.

[0061] Except for the positions avoiding the first grooves, the columns 9 on the first inner surface of the first cover body 1 can be arranged as evenly as possible, so that the working medium in the second state can flow more evenly in the direction away from the evaporation end of the heat source 6 of the second cover body 2, realizing uniform heat dissipation.

[0062] In some embodiments, the second working medium transport layer 5 includes a second groove capillary structure 10. Similar to the first groove capillary structure 8, the second groove capillary structure 10 refers to a groove structure with capillary force. Through the second groove capillary structure 10, a second part of the working medium can be quickly refluxed to the evaporation end where the heat source 6 of the second cover body 2 is located under the action of the capillary force of the second groove capillary structure 10.

[0063] The second groove capillary structure 10 may include a plurality of second grooves. Similar to the arrangement of the first grooves, the second grooves are arranged in a divergent shape relative to the heat source 6, and the divergent arrangement will not be elaborated here. It should be noted that the density of the second grooves can be greater than the density of the first grooves.

[0064] Combined with the above embodiments, because the working medium has a certain weight, a large part of the working medium cooled at the condensation end will settle towards the second cover body 2 under the action of gravity. The amount of the working medium in the first state after settlement is more than the amount of the working medium on the first inner surface of the first cover body 1. Or rather, most of the working medium cooled from the second state to the first state has settled on the second inner surface of the second cover body 2. Therefore, the density of the second grooves provided on the second inner surface of the second cover body 2 can be greater than the density of the first grooves on the inner surface of the first cover body 1, so that the working medium changed from the second state to the first state on the second inner surface of the second cover body 2 can be transported back to the evaporation end where the heat source 6 of the second cover body 2 is located more quickly, accelerating the liquid return speed, improving the reflux efficiency of the cooled working medium in the first state, and further enabling the working medium at the evaporation end position corresponding to the heat source 6 of the second cover body 2 to absorb heat again and change into the working medium in the second state, enhancing the vapor-liquid circulation efficiency, and thus improving the overall heat dissipation efficiency of the heat dissipation device.

[0065] In addition, too many first groove structures cannot be arranged on the first cover body 1. Otherwise, on the one hand, it will affect the setting of the columns 9 and thus affect the strength of the heat dissipation device. On the other hand, when the first cover body 1 is used as a condensation surface, arranging more first grooves on the first cover body 1 for the reflux of the first part of the working medium will affect the direct contact between the working medium in the second state and the first cover body 1 and thus affect the heat dissipation effect, making the overall performance of the heat dissipation device worse.

[0066] In some embodiments, combined with Figure 4 , the second working medium transport layer 5 includes a plurality of third groove capillary structures 11. The third groove capillary structure 11 refers to a groove structure with capillary force.

[0067] A plurality of third grooves are coaxially arranged around the position of the heat source 6 corresponding to the second inner surface of the second cover body 2. Combining Figure 5 , the plurality of third grooves divide the second groove into multiple segments. By the cooperation of the plurality of third grooves and the second groove, the working fluid in the first state at a position far from the heat source 6 can be quickly bypassed the heat source 6 to the evaporation end where the heat source 6 of the second cover body 2 is located under the capillary force of the capillary structure 11 of the third groove. Specifically, the working fluid in the first state can flow along the third groove around the position where the heat source 6 is located, so that the working fluid in the third groove can be continuously adsorbed by the multiple second grooves respectively communicating with the third groove and flow towards the direction close to the heat source 6. Combining Figure 4 , the third groove can be an annular shape or a part of an annulus. For example, the third groove close to the heat source 6 can be a complete annular shape, while the third groove far from the heat source 6 may be formed as a part of an annulus due to the limitation of the edge of the second surface of the second cover body 2. Of course, it can be understood that the third groove can also be arranged in other ways, and only this is taken as an example, which does not constitute a limitation on the protection scope of the claims.

[0068] The groove width of one end of the second groove segment close to the evaporation end is greater than that of the end far from the evaporation end, so as to improve the capillary force of the second groove, making it easier for the working fluid in the first state to be adsorbed by the second groove and flow back to the evaporation end of the heat source 6 of the second cover body 2. The plurality of third grooves divide the second groove into multiple segments, which can make the length of the second groove in the divergent direction shorter, so that the width difference between the two ends of the second groove is smaller, and the adsorption effect of the second groove on the working fluid in the first state is improved. If the second groove is not segmented, due to the relatively long length of the second groove, the width difference between the two ends of the second groove is relatively large, affecting the capillary force of the second groove and the capillary effect is poor.

[0069] Of course, it can be understood that the second groove can also be set with equal width at the beginning, that is, the width of a second groove is the same at each position. However, in this design, there will be some areas on the second inner surface of the second cover body 2 far from the heat source 6 where the second groove cannot be set.

[0070] In some embodiments, the second working fluid transport layer 5 includes a fourth groove capillary structure 12.

[0071] Combining Figure 6 , the fourth groove capillary structure 12 includes a plurality of fourth grooves. The plurality of fourth grooves are arranged in parallel, and at least part of the plurality of fourth grooves pass through the position of the second inner surface of the second cover body 2 corresponding to the heat source 6. The widths of the plurality of fourth grooves arranged in parallel can be the same. From the processing technology, the plurality of fourth grooves arranged in parallel are easier to process than the divergent arrangement, and the processing cost is lower.

[0072] In addition, the above-mentioned first working fluid transport layer 4 and second working fluid transport layer 5 can be formed by, but are not limited to, the method of micro-etching grooves. Since the etching grooves are formed on the inner surface of the airtight cavity (including the first inner surface of the first cover and the second inner surface of the second cover), the setting of the first working fluid transport layer 4 and the second working fluid transport layer 5 does not increase the thickness of the heat dissipation device. Without increasing the area, thickness, and weight of the heat dissipation device, the heat dissipation effect of the heat dissipation device is improved. In addition, by the method of etching and setting grooves, the weight of the heat dissipation device can also be reduced to a certain extent, making the electronic device using this heat dissipation device more portable.

[0073] An embodiment of the present application further provides an electronic device, including the heat dissipation device as described in any one of the above embodiments and a heat source 6. The heat source 6 is disposed at the evaporation end of the second cover of the heat dissipation device. The first cover 1 and the second cover 2 of the heat dissipation device are arranged opposite to each other and connected to form an airtight cavity 3 for accommodating a cooling working fluid. The working fluid has a first state and a second state. The working fluid in the first state absorbs heat and changes from the first state to the second state, and the working fluid in the second state cools and changes from the second state to the first state.

[0074] The first working fluid transport layer 4 of the heat dissipation device is disposed on the first inner surface of the first cover 1 opposite to the second cover 2. The second working fluid transport layer 5 of the heat dissipation device is disposed on the second inner surface of the second cover 2 opposite to the first cover 1.

[0075] Among them, the working fluid that changes from the second state to the first state when encountering cold at the first cover 1 includes a first part and a second part. The first part flows back to the evaporation end where the heat source 6 of the second cover 2 is located through the first working fluid transport layer 4, and the second part flows back to the evaporation end where the heat source 6 of the second cover 2 is located through the second working fluid transport layer 5.

[0076] The electronic device can be, but is not limited to, a notebook computer, an iPad, a mobile phone, etc. With the popularization of large desktop 3D games to mobile electronic devices, as well as the development and implementation of AI large models on the edge side, the requirements for improving the limit power of mobile device processors are getting higher and higher, and the demand for improving the heat dissipation capacity is increasing rapidly. For mobile electronic devices such as tablet computers, pure passive heat dissipation is mainly adopted in the thin and light body at present. The heat dissipation capacity of the heat dissipation device determines the performance upper limit of the tablet computer. However, the thin and light body limits the thickness of the heat dissipation device. In the limited thickness space, the traditional design scheme has reached a bottleneck. The heat dissipation capacity of the above-mentioned electronic device provided by the present application is improved, ensuring the use performance of the electronic device.

[0077] The above has described multiple embodiments of the present application in detail. However, the present application is not limited to these specific embodiments. Based on the concept of the present application, those skilled in the art can make various variations and modifications to the embodiments, and these variations and modifications should all fall within the scope claimed by the present application.

Claims

1. A heat dissipation device, comprising: a first cover and a second cover; The first cover body and the second cover body are arranged opposite to each other and connected to form an airtight cavity, and the airtight cavity is used to accommodate a cooling medium; the medium has a first state and a second state, wherein the medium in the first state absorbs heat and changes from the first state to the second state, and the medium in the second state cools and changes from the second state to the first state; A first working medium transport layer is disposed on a first inner surface of the first cover body opposite to the second cover body; A second working fluid transport layer is arranged on the second inner surface of the second cover body opposite to the first cover body; wherein the working fluid that changes from the second state to the first state when cooled at the first cover body includes a first part and a second part, the first part flows back to the evaporation end of the second cover body where the heat source is located through the first working fluid transport layer, and the second part flows back to the evaporation end of the second cover body where the heat source is located through the second working fluid transport layer.

2. The heat dissipation device according to claim 1 further comprises a third working fluid transport layer, which is arranged between the first inner surface and the second inner surface; the second part flows back to the evaporation end where the heat source of the second cover is located through the third working fluid transport layer and the second working fluid transport layer.

3. According to the heat dissipation device of claim 1, the first working fluid transport layer is a first groove capillary structure, and the first groove capillary structure includes a plurality of first grooves, and the plurality of first grooves are arranged in a divergent shape relative to the evaporation end so that the first part can flow back to the evaporation end where the heat source of the second cover body is located along the plurality of first grooves in multiple directions.

4. According to the heat dissipation device of claim 3, the plurality of first grooves are arranged in a divergent shape relative to the evaporation end, including: the first ends of the plurality of first grooves are located at the position of the first inner surface of the first cover body corresponding to the heat source, and the second ends of the plurality of first grooves extend to the edge position of the first inner surface of the first cover body.

5. The heat dissipation device according to claim 3, wherein the first inner surface of the first cover body is provided with a column extending into the airtight cavity, the column abuts against the second inner surface of the second cover body, and the orthographic projection of the column on the first inner surface of the first cover body avoids the plurality of first grooves. 6 . The heat dissipation device according to claim 3 , wherein the second working medium transport layer comprises a second groove capillary structure, the second grooves are arranged in a divergent shape relative to the heat source, and the density of the second grooves is greater than the density of the first grooves.

7. The heat dissipation device according to claim 6, wherein the second working medium transport layer comprises a plurality of third groove capillary structures; The plurality of third grooves are coaxially arranged around the second inner surface of the second cover body corresponding to the position of the heat source; the plurality of third grooves divide the second groove into a plurality of segments. 8 . The heat dissipation device according to claim 7 , wherein a groove width of an end of the second groove section close to the evaporation end is greater than a groove width of an end of the second groove section far from the evaporation end.

9. The heat dissipation device according to claim 1, wherein the second working medium transport layer comprises a fourth groove capillary structure; The fourth groove capillary structure includes a plurality of fourth grooves, the plurality of fourth grooves are arranged in parallel, and at least a portion of the plurality of fourth grooves corresponds to the position of the heat source through the second inner surface of the second cover body.

10. An electronic device, comprising a heat sink and a heat source as claimed in any one of claims 1 to 9, wherein the heat source is arranged at the evaporation end of the second cover of the heat sink, the first cover and the second cover of the heat sink are arranged opposite to each other and connected to form an airtight cavity, the airtight cavity is used to accommodate a cooling medium; the medium has a first state and a second state, wherein the medium in the first state absorbs heat and changes from the first state to the second state, and the medium in the second state cools and changes from the second state to the first state; The first working medium transport layer of the heat dissipation device is arranged on a first inner surface of the first cover body opposite to the second cover body; The second working medium transport layer of the heat dissipation device is arranged on the second inner surface of the second cover body opposite to the first cover body; in, The working fluid that changes from the second state to the first state when cooled at the first cover body includes a first part and a second part, the first part flows back to the evaporation end where the heat source of the second cover body is located through the first working fluid transport layer, and the second part flows back to the evaporation end where the heat source of the second cover body is located through the second working fluid transport layer.

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