Heat dissipation module, electronic device and electronic device protective case

Abstract

The present invention relates to the field of fluid transport technology, and in particular to a heat dissipation module, an electronic device and an electronic device protective shell, wherein the heat dissipation module comprises a main unit and at least one actuating unit, wherein the main unit has a flow channel for a heat dissipating medium to flow therein, and the actuating unit is used to provide power for the circulation of the heat dissipating medium in the circulation flow path. The heat dissipation module of the present invention is provided with an expansion chamber on the flow channel, and at least a portion of the main unit opposite to the expansion chamber is formed as a flexible portion, so that the heat dissipation module can effectively work in a first mode in which the heat dissipating medium does not undergo a phase change, and can also work in a second mode in which the heat dissipating medium undergoes a phase change. By causing at least the expansion chamber of the main unit to expand or contract in volume as the gas pressure in the flow channel changes, the gas pressure in the flow channel can be effectively maintained basically unchanged, and the saturation temperature of the heat dissipating medium will basically not change, thereby allowing the phase change process to continue substantially uninhibited.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid transportation, and in particular to a heat dissipation module, an electronic device comprising the heat dissipation module, and an electronic device protective shell comprising the heat dissipation module. Background Art

[0002] The miniaturization and high integration of high-power electronic components have led to a rapid increase in the heat generated by electronic components. The local high temperature of the equipment caused by the failure to dissipate heat in time will seriously affect the temperature uniformity of the equipment and the overall performance of the electronic equipment. Studies have shown that when working at a temperature higher than the rated operating temperature, the reliability of semiconductor electronic components will be greatly reduced. At the same time, about 20% of the failures of high-precision electronic equipment are caused by the excessive temperature of the heating components. Efficient heat dissipation of high-heating components in a limited space has become an important factor in ensuring the stable operation of electronic equipment.

[0003] The pump-driven microchannel two-phase flow circulation cooling and heat dissipation technology is considered to be one of the most effective cooling technologies for high-power circuits such as integrated circuits. It can effectively solve the cooling problems of small channels, high heat loads, high precision, multiple heat sources or complex distributed heat sources through high-performance power equipment and circulating working fluids. In existing pump-driven microchannel two-phase flow circulation cooling systems, mechanical pumps are mostly used to provide circulation power. For example, a patent application for an active heat pipe heat dissipation device disclosed in a Chinese patent with publication number CN108509004A mainly uses a mechanical pump to transport liquid working fluids. Since the mechanical pump can only pump liquids, a liquid reservoir needs to be added in front of the mechanical pump inlet pipeline. At the same time, the inlet liquid temperature must have a certain degree of supercooling to avoid cavitation and affect the reliability of the system.

[0004] Against this background, in recent years, a microchannel two-phase circulation cooling system has emerged that uses a micro pump (such as a piezoelectric pump) to replace a mechanical pump. For example, the phase change heat transfer cooling system described in a microchannel phase change heat transfer cooling system based on a piezoelectric pump disclosed in a Chinese patent with publication number CN207519054U includes a piezoelectric pump, a microchannel evaporator, and a radiator. The liquid working fluid absorbs heat and changes phase in the microchannel evaporator to form a gas-liquid two-phase flow. After reaching the radiator, it condenses into a liquid phase, releases latent heat, and then reaches the next cycle through the piezoelectric pump. By introducing a piezoelectric pump to replace the traditional mechanical pump, the advantages of compact structure, low noise, and low power consumption can be achieved. At the same time, the phase change heat transfer of the liquid working fluid can theoretically improve the heat exchange and heat transfer efficiency, but there are still some problems:

[0005] On the one hand, in the prior art, the closed-loop pipeline containing the heat dissipation medium is made of a rigid or non-deformable structure. When the heat dissipation medium contained in the pipeline reaches its saturation temperature, the heat dissipation medium absorbs heat and changes phase from liquid phase to gas phase, which increases the gas pressure in the pipeline, thereby increasing the saturation temperature of the heat dissipation medium, which in turn inhibits the continuous phase change process of the heat dissipation medium. Further phase change requires the heat dissipation medium to reach a higher saturation temperature, and the corresponding heat source temperature will also increase, which is not conducive to heat dissipation.

[0006] On the other hand, the heat dissipation medium in the pipeline is a single type of heat dissipation medium. The heat load of the microchannel evaporator is directly related to the evaporation rate of the single medium. A relatively low heat load may cause the medium to not undergo phase change, resulting in limited heat dissipation efficiency. However, an excessively high heat load may cause the medium to undergo phase change and evaporate to dryness. The fluctuation of the heat load will have a great impact on the stability of the system. It is difficult to find a suitable single type of heat dissipation medium for fluctuating heat loads, especially those with large fluctuations.

[0007] Furthermore, the input and output performance of the piezoelectric pump is greatly affected by the composition of the fluid. When pure liquid phase fluid flows through the piezoelectric pump, the inlet of the piezoelectric pump can provide a continuous and stable high negative pressure. When gas-liquid two-phase fluid flows through the piezoelectric pump, the negative pressure at the inlet of the piezoelectric pump continues to decrease with the increase of the amount of gas phase fluid mixed in, and the output performance of the piezoelectric pump decreases accordingly, which greatly weakens the flow limit of the phase change heat cooling system, thereby causing evaporation or liquid plugging problems, seriously affecting the working stability and reliability of the system. Therefore, the piezoelectric pump is usually set in the condensation section of the loop. Summary of the invention

[0008] The technical problem to be solved by the present invention is: in order to solve the deficiencies in the prior art, a heat dissipation module is provided, and an electronic device including the above heat dissipation module and an electronic device protective shell including the above heat dissipation module are also provided. The heat dissipation module can solve the problem of phase change inhibition caused by the rigid or difficult-to-deform structure of the closed-loop pipeline containing the heat dissipation medium in the prior art. In addition, the present invention can also solve the problem that a single heat dissipation medium is difficult to adapt to a larger range of heat load fluctuations and the efficiency of the power device caused by the gas-liquid two-phase flow is reduced, resulting in evaporation or liquid plugging.

[0009] The technical solution adopted by the present invention to solve the technical problem is: a heat dissipation module, comprising a main unit and at least one actuating unit, wherein the main unit has a flow channel for a heat dissipation medium to flow, wherein the flow channel and the actuating unit cooperate to form a closed circulation flow path, wherein the actuating unit is used to provide power for the circulation flow of the heat dissipation medium in the circulation flow path, and wherein the heat dissipation module has a first mode in which the heat dissipation medium does not undergo a phase change and a second mode in which the heat dissipation medium undergoes a phase change;

[0010] A portion of the flow channel is formed as an expansion chamber, and there is at least one expansion chamber. At least the portion of the main unit opposite to the expansion chamber is formed as a flexible portion, and the flexible portion can be deformed to cause the volume of the flow channel to expand or contract as the gas pressure in the flow channel changes.

[0011] Furthermore, the portion of the flow channel other than the expansion cavity is a main body section, the main body section is connected to the expansion cavity, and the cross-sectional area of ​​the expansion cavity is larger than the cross-sectional area of ​​the main body section.

[0012] Furthermore, the lateral width of the expansion chamber in the lateral direction perpendicular to the flow direction of the heat dissipating medium therein is W1, and the lateral width of the main body section in the lateral direction perpendicular to the flow direction of the heat dissipating medium therein is W2, and W1>W2.

[0013] Furthermore, the main unit has a heat absorption section for absorbing heat from the heat source, the flow channel extends to the heat absorption section, and the position of the expansion chamber is set to allow the heat dissipation medium to pass through the expansion chamber during the process of flowing from the heat absorption section to the actuating unit along the flow channel.

[0014] Furthermore, the heat dissipation medium in the flow channel is of a single type, and the heat dissipation medium is fluorinated liquid or silicone oil.

[0015] Furthermore, the heat dissipation medium in the flow channel is a mixed heat dissipation medium, and the mixed heat dissipation medium has at least one base liquid and at least one dispersion liquid;

[0016] Under the same gas pressure, all base liquids and all dispersed liquids constituting the mixed heat dissipation medium have different saturation temperatures.

[0017] Furthermore, all base liquids and all dispersed liquids constituting the mixed heat dissipation medium are immiscible with each other.

[0018] Furthermore, the base liquid is water, methanol, ethanol or quicksand oil, and the dispersion liquid is fluorinated liquid or silicone oil.

[0019] Furthermore, under the same gas pressure, the saturation temperature of any base liquid is greater than the saturation temperature of the dispersion liquid, and there is always a portion of the base liquid that does not participate in the phase change heat.

[0020] Regarding the actuation unit, the following two options are available:

[0021] First, the actuating unit includes an actuating element and a cavity arranged inside the main unit;

[0022] Both sides of the cavity are connected to the flow channel, and an inlet check valve and an outlet check valve are respectively provided on both sides of the cavity. The inlet check valve allows the heat dissipation medium to flow from the flow channel to the cavity, and the outlet check valve allows the heat dissipation medium to flow from the cavity to the flow channel. The actuating element is arranged in an area outside the main unit opposite to the cavity, and is used to cause the cavity to produce a volume change.

[0023] Secondly, the actuating unit is a fluid pump, and the outside of the main unit has at least one liquid inlet and at least one liquid outlet connected to the flow channel, the liquid inlet is connected to the fluid outlet of the fluid pump, and the liquid outlet is connected to the fluid inlet of the fluid pump, and the fluid pump provides power for the unidirectional circulation of the heat dissipation medium in the circulation flow path.

[0024] Furthermore, the main body unit is composed of at least two layers of film materials, and all the film materials are stacked and sealed together to form at least one closed space, which constitutes the flow channel.

[0025] Furthermore, the main unit has an upper membrane material, an intermediate membrane material and a lower membrane material which are stacked in sequence along its thickness direction, and a gap structure is opened on the intermediate membrane material, and the gap structure is a groove portion and / or a hole portion that penetrates the intermediate membrane material, and the upper membrane material and the lower membrane material cover the gap structure to form the flow channel.

[0026] Furthermore, the material constituting the upper membrane material, the middle membrane material and the lower membrane material is at least one of a polymer material, a metal material or a functional material composited with a polymer material and a metal material.

[0027] Furthermore, the main body unit is formed in a patch shape with a thickness of 0.01 mm to 2 mm, and the equivalent diameter of the flow channel is 10 μm to 1 mm.

[0028] The present invention also provides an electronic device, comprising the above-mentioned heat dissipation module.

[0029] The present invention also provides an electronic equipment protection cover, comprising the above-mentioned heat dissipation module.

[0030] The beneficial effects of the present invention are:

[0031] 1) The heat dissipation module of the present invention is provided with an expansion chamber on the flow channel. At the same time, at least the part of the main unit opposite to the expansion chamber is formed into a flexible part, and can produce deformation that causes the flow channel volume to expand or contract as the gas pressure in the flow channel changes, so that the heat dissipation module can effectively work in the first mode where the heat dissipation medium does not undergo phase change, and can also work in the second mode where the heat dissipation medium undergoes phase change. In the first mode, the heat sink does not undergo phase change, and the heat sink in the flow channel circulates in a pure liquid phase. The local pressure change caused by the actuating unit will not cause a significant change in the gas pressure in the flow channel, and the setting of the expansion chamber does not hinder the directional circulation of the liquid phase heat sink. In the second mode, the heat sink undergoes an endothermic phase change from liquid to gas and / or an exothermic phase change from gas to liquid. The phase change process will cause the gas pressure in the flow channel to change, and at least the expansion chamber of the main unit will produce a volume expansion or contraction deformation as the gas pressure in the flow channel changes, which can effectively maintain the gas pressure in the flow channel basically unchanged, and the saturation temperature of the heat sink will basically not change, so that the phase change process can continue substantially uninhibited, thereby improving the heat dissipation efficiency.

[0032] 2) The heat dissipation module of the present invention can work in the first mode where the heat dissipation medium does not undergo phase change, and can also work in the second mode where the heat dissipation medium undergoes phase change. It can adapt to a larger range of thermal load fluctuations and has a wide range of applications. In the first mode, the actuating unit causes the liquid heat dissipating medium to circulate in the flow channel, quickly and evenly dissipating the heat of the heat source in contact with the main unit to the entire main unit, thereby reducing the temperature of the heat source and improving the heat dissipation efficiency. The first mode is suitable for scenarios with relatively low heat loads. In the second mode, along with the heat absorption and heat release phase changes of the heat dissipating medium, a gas-liquid two-phase flow is formed in the flow channel, and only a small part of the gas-phase heat dissipating medium will be mixed into the liquid-phase heat dissipating medium to form an air column. Most of the gas-phase heat dissipating medium will cause the gas pressure in the flow channel to increase, causing at least the expansion chamber of the main unit to expand in volume, and the liquid-phase heat dissipating medium will be contained in the air chamber formed by the volume expansion of at least the expansion chamber of the main unit. Therefore, the heat dissipating medium flowing through the heat absorption section substantially remains in the liquid phase when it reaches the actuating unit, and the actuating efficiency of the actuating unit will not be greatly reduced due to the mixing of a large amount of gas-phase medium, thereby improving the stability and reliability of the heat dissipation module.

[0033] 3) The heat dissipation module of the present invention can use either a single type of heat dissipation fluid or a mixed phase change fluid. First, an expansion chamber is provided on the flow channel. At the same time, at least the portion of the main unit opposite to the expansion chamber is formed into a flexible portion, and can produce deformation that causes the volume of the flow channel to expand or contract as the gas pressure in the flow channel changes, thereby solving the problem of phase change inhibition in the phase change heat transfer process when a single type of heat dissipation fluid is used in the prior art; secondly, more preferably, by designing the composition form of the mixed phase change fluid, it has higher feasibility in matching the phase change heat transfer cooling system with fluctuating heat load or heat flux density. In addition, by controlling the proportion of each component in the mixed phase change fluid composed of several easily available base liquids and dispersion liquids, a good matching effect can be achieved, and the phase change process can be actively controlled.

[0034] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0036] Figure 1 It is a schematic diagram of the main unit using two layers of membrane material stacked and sealed together to form a flow channel;

[0037] Figure 2 It is a schematic diagram of the main unit using three layers of membrane materials stacked and sealed together to form a flow channel;

[0038] Figure 3 A schematic diagram of a heat dissipation module of an actuating unit configured in the first solution;

[0039] Figure 4 A schematic diagram of a heat dissipation module of an actuating unit configured in the second solution;

[0040] Figure 5 It is a schematic diagram of the expansion cavity when it expands and deforms;

[0041] Figure 6 It is a schematic diagram of Example 4;

[0042] Figure 7 This is a schematic diagram of Example 5.

[0043] In the figure: 1, main unit, 11, flow channel, 111, main section, 112, expansion chamber, 12, heat absorption section, 1-1, upper membrane material, 1-2, middle membrane material, 1-3, lower membrane material;

[0044] 2. actuating element, 3. chamber, 4. inlet check valve, 5. outlet check valve;

[0045] 6. Fluid pump;

[0046] 7. Electronic equipment housing;

[0047] 8. Protective cover;

[0048] 9. Heating element.

[0049] W1: the transverse width of the expansion chamber in the transverse direction perpendicular to the flow direction of the heat dissipating medium therein;

[0050] W2: The transverse width of the main body section in the transverse direction perpendicular to the flow direction of the heat dissipation medium therein. DETAILED DESCRIPTION

[0051] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams that only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention, and directions and references (e.g., up, down, left, right, etc.) may only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not to be taken in a limiting sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0052] Embodiment 1, as Figure 1-4 As shown, a heat dissipation module comprises a main unit 1 and at least one actuating unit, wherein the main unit 1 has a flow channel 11 for the flow of heat dissipation medium;

[0053] The main unit 1 is composed of at least two layers of membrane materials, all of which are stacked and sealed together to form at least one closed space, which constitutes a flow channel 11. Adjacent membrane materials are joined together by relative surface sealing, which can be performed by bonding, welding or other methods that can achieve effective surface connection. According to the shape and distribution of the surface sealing area, the flow channel 11 can be either a single path or a multi-path with bifurcations. The multi-path flow channel 11 includes at least two mutually intersecting and connected bifurcations, which is not limited here. The cross-sectional form of the flow channel 11 can be as follows Figure 1-2 In the form shown, in this embodiment, the main unit 1 is composed of three layers of film materials, including an upper film material 1-1, an intermediate film material 1-2 and a lower film material 1-3 which are sequentially stacked along the thickness direction thereof, and a gap structure is provided on the intermediate film material 1-2, and the gap structure is a groove portion and / or a hole portion penetrating the intermediate film material 1-2, and the upper film material 1-1 and the lower film material 1-3 cover the gap structure to form a flow channel 11. In addition, the intermediate film material 1-2 can be integrally formed with the upper film material 1-1, or the intermediate film material 1-2 can be integrally formed with the lower film material 1-3.

[0054] The materials of the upper film material 1-1, the middle film material 1-2 and the lower film material 1-3 constituting the main unit 1 can be at least one of polymer materials, metal materials, and functional materials composited from polymer materials and metal materials. The specific types are not limited here. It is required that the materials constituting the main unit 1 do not or are difficult to produce physical and chemical reactions with the heat dissipation medium filled in the flow channel 11. It is more ideal that the materials of the upper film material 1-1, the middle film material 1-2 and the lower film material 1-3 constituting the main unit 1 are all polymer materials, such as PC, PP or PET, etc., or functional materials composited from a variety of polymer materials. The advantages of selecting polymer materials are that, on the one hand, the lamination and sealing process between polymer plastic film materials is relatively mature, and it is easy to achieve high-strength sealing connection between adjacent film materials; on the other hand, the materials are easy to obtain, low in cost, environmentally friendly and pollution-free. By selecting the appropriate type of polymer plastic film material, it can be industrial grade, food grade and medical grade, which greatly expands the application range of the product; furthermore, there is no electromagnetic interference, which is conducive to the development of new application scenarios in electronic terminal products. In addition, the main unit 1 is endowed with excellent flexibility. The main unit 1 is formed into a flexible patch shape, which can be bent and twisted, and can be shaped and formed into a set shape by heating and pressurizing the various layers of film materials constituting the main unit 1 or the main unit 1 after sealing and forming, so that the main unit 1 can form a good 3D fit with the bonding surface during the application of the heat dissipation module, reduce the interface thermal resistance, and improve the heat exchange efficiency.

[0055] The thickness of the main unit 1 can be 0.01mm~2mm, and the equivalent diameter of the flow channel 11 can be 10μm~1mm. Based on this, even if the main unit 1 is made of polymer material, it has a heat dissipation efficiency comparable to that of metal materials. The scale of the flow channel 11 is controlled at the microchannel level. The microchannel has a large surface area to volume ratio to further improve the heat exchange efficiency of the main unit 1. At the same time, the overall liquid filling volume is small and the weight is light.

[0056] It is worth noting that each membrane material layer is stacked and joined together by relative surface sealing. The relative surface sealing can be carried out by bonding, welding or other methods that can achieve effective surface connection. According to the shape and distribution of the surface sealing area, the formed flow channel 11 can be either a single path or a multi-path with divergent paths, but is not limited to this. For example, the lateral span of the flow channel 11 other than the expansion chamber 112 in the lateral direction perpendicular to the flow direction of the heat dissipation medium can be the same, which is equivalent to an equal-section flow path, or can be different, which is equivalent to a variable-section flow path. In addition, for example, in the structural form of the main unit 1 composed of three layers of membrane materials, the upper membrane material 1-1 and the lower membrane material 1-3 can be sealed at the outermost periphery of the main unit 1, and the middle membrane material 1-2 is actually squeezed or riveted between the upper membrane material 1-1 and the lower membrane material 1-3 to form a main unit 1 with an internal flow channel 11.

[0057] The flow channel 11 and the actuating unit cooperate to form a closed circulation flow path, and the actuating unit is used to provide power for the circulation of the heat dissipating medium in the circulation flow path.

[0058] The actuating unit may be, but is not limited to, the following two solutions:

[0059] Actuating unit of the first solution:

[0060] The actuating unit includes an actuating element 2 and a cavity 3 arranged inside the main unit 1. The cavity 3 is also a closed space formed by stacking and sealing all the membrane materials together, that is, the cavity 3 is a part of the actuating unit. The cavity 3 is connected with the flow channel 11 to form a closed circulation flow path. Both sides of the cavity 3 are connected with the flow channel 11, and an inlet check valve 4 and an outlet check valve 5 are respectively arranged on both sides of the cavity 3. The inlet check valve 4 allows the heat dissipation medium to flow from the flow channel 11 to the cavity 3, but prevents the heat dissipation medium from flowing from the cavity 3 to the flow channel 11. 1, the outlet one-way valve 5 allows the heat dissipation medium to flow from the cavity 3 to the flow channel 11, but prevents the heat dissipation medium from flowing from the flow channel 11 to the cavity 3. The actuator 2 may be, but is not limited to, a piezoelectric vibrator, an electromagnetic actuator, an electrostatic actuator, an actuator formed by a shape memory metal, or an actuator of a micro-mechanical piston type. In this embodiment, the actuator 2 is a piezoelectric vibrator as an example. The piezoelectric vibrator is arranged in the area outside the main unit 1 opposite to the cavity 3 to cause the cavity 3 to produce a volume change, thereby providing power for the one-way circulation flow of the heat dissipation medium. The piezoelectric vibrator arranged outside the main unit 1, the cavity 3 formed inside the main unit 1, and the inlet one-way valve 4 and the outlet one-way valve 5 arranged on both sides of the cavity 3 cooperate to realize the pumping effect of the fluid pump 6, such as Figure 3 As shown; for example, the fluid delivery device disclosed in the Chinese patents with publication numbers CN116322001A, CN116293000A and CN1158400A can be used as a specific embodiment of the actuating unit and is also protected in this application;

[0061] The actuating unit of the second scheme:

[0062] The actuating unit is a fluid pump 6. The outside of the main unit 1 has at least one liquid inlet and at least one liquid outlet connected to the flow channel 11. The fluid pump 6 can be, but is not limited to, a micro piezoelectric pump, a micro electromagnetic pump, or a micro electrostatic pump. In this embodiment, the fluid pump 6 adopts a micro piezoelectric pump as an example. The liquid inlet of the flow channel 11 is connected to the fluid outlet of the micro piezoelectric pump, and the liquid outlet of the flow channel 11 is connected to the fluid inlet of the micro piezoelectric pump. The micro piezoelectric pump and the flow channel 11 cooperate to form a closed circulation flow path. The micro piezoelectric pump provides power for the unidirectional circulation flow of the heat dissipation medium, such as Figure 4As shown; a liquid-cooling heat dissipation module, a liquid-cooling heat dissipation system, and a matching form of a flow channel and a power pump in an electronic device disclosed in Chinese patent publication number CN111818770A (pump-driven closed circulation flow channel), a bendable liquid-cooling heat dissipation module and a matching form of a flow channel matrix and a micro pump in a foldable screen electronic terminal disclosed in Chinese patent publication number CN115167646A (pump-driven closed circulation flow channel), and a liquid-cooling heat dissipation module, a liquid-cooling heat dissipation system, and a matching form of a flow channel and a power pump in an electronic device disclosed in Chinese patent CN212573382U (pump-driven closed circulation flow channel) can all be used as the matching form of the piezoelectric pump and the flow channel 11 in this embodiment, and are also protected in this application.

[0063] like Figure 3 and 4 As shown, a portion of the flow channel 11 is formed as an expansion chamber 112, and there is at least one expansion chamber 112. At least a portion of the main unit 1 opposite to the expansion chamber 112 is formed as a flexible portion. Figure 5 As shown, the flexible portion can produce deformation causing the volume of the flow channel 11 to expand or contract as the gas pressure in the flow channel 11 changes. When the gas pressure in the flow channel 11 changes, at least the expansion chamber 112 of the main unit 1 can produce volume expansion or contraction deformation on one side or both sides along the thickness direction of the main unit 1 to balance the pressure in the flow channel 11, thereby effectively maintaining the gas pressure in the flow channel 11 basically unchanged.

[0064] The heat dissipation module has a first mode in which the heat dissipation medium does not undergo phase change and a second mode in which the heat dissipation medium undergoes phase change;

[0065] The heat dissipation module can work in a first mode in which the heat dissipation medium does not undergo a phase change, or in a second mode in which the heat dissipation medium undergoes a phase change. At the same time, the heat dissipation medium filled in the flow channel 11 can be a single type of heat dissipation medium, such as a low-viscosity, low-boiling-point fluorinated liquid such as FC3283 and FC72, or a low-viscosity, low-boiling-point silicone oil, so that the heat dissipation module has a lower starting temperature so as to respond quickly to the temperature change of the heat source; the heat dissipation medium filled in the flow channel 11 can also be a mixed heat dissipation medium composed of at least one base liquid and at least one dispersed liquid. Under the same gas pressure, all base liquids and all dispersed liquids that constitute the mixed heat dissipation medium each have different saturation temperatures. Therefore, a heat dissipation medium with a saturation temperature that meets the design requirements can be obtained by mixing multiple heat dissipation mediums, thereby solving the problem that it is difficult to find and obtain a suitable single type of heat dissipation medium. It is more ideal that all base liquids and all dispersed liquids constituting the mixed heat dissipation medium are immiscible with each other, and the saturation temperature magnitudes thereof are distributed in a gradient at the same gas pressure. Preferably, the minimum value of the saturation temperature gradient formed by all base liquids constituting the mixed liquid is greater than the maximum value of the saturation temperature gradient formed by all dispersed liquids, which is equivalent to that, at the same gas pressure, the saturation temperature of any base liquid is greater than the saturation temperature of the dispersed liquid, that is, the base liquid has a higher saturation temperature than the dispersed liquid at the same gas pressure, that is, a higher heat load is required to induce a phase change in the base liquid. For example, the base liquid may be one of low-viscosity and high-boiling-point liquids such as water, methanol, ethanol, and quicksand oil, and the dispersed liquid may be one or both of the above-mentioned fluorinated liquid and silicone oil.

[0066] It is understandable that, generally speaking, the same liquid has different saturation temperatures under different gas pressures, and different liquids also have different saturation temperatures under the same gas pressure. When the liquid temperature reaches its saturation temperature under a certain gas pressure, the liquid will undergo a phase change from a liquid phase fluid to a gas phase fluid, and this process is accompanied by the absorption of heat. When the temperature is lower than its saturation temperature under the gas pressure, the gas phase fluid will be transformed back into a liquid phase fluid, and this process is accompanied by the release of heat. At the same time, it is understandable that the saturation temperature of the same liquid increases with the increase of gas pressure and decreases with the decrease of gas pressure.

[0067] From this, it is not difficult to understand that

[0068] In the first mode, the heat dissipation medium does not undergo phase change, and the actuating unit causes the liquid heat dissipation medium to circulate, quickly and evenly dissipating the heat of the heat source in contact with the main unit 1 to the entire main unit 1, thereby reducing the temperature of the heat source and improving the heat dissipation efficiency. The first mode is suitable for scenes with relatively low heat loads. The heat dissipation medium in the flow channel 11 circulates in a pure liquid phase. The local pressure change caused by the actuating unit will not cause a significant change in the gas pressure in the flow channel 11, and the setting of the expansion chamber 112 does not hinder the directional circulation of the liquid heat dissipation medium.

[0069] In the second mode, the heat dissipation medium undergoes an endothermic phase change from liquid to gas and / or an exothermic phase change from gas to liquid. The phase change process will cause the gas pressure in the flow channel 11 to change. When the heat dissipation medium undergoes an endothermic phase change from liquid to gas, the gas pressure in the flow channel 11 increases and is greater than the external gas pressure, which will cause at least the expansion chamber 112 of the main unit 1 to undergo volume expansion deformation, and the volume expansion of at least the expansion chamber 112 of the main unit 1 will reduce the gas pressure in the flow channel 11. That is, the gas pressure in the flow channel 11 is maintained basically unchanged by the volume expansion of at least the expansion chamber 112 of the main unit 1, and the phase change temperature of the liquid heat dissipation medium will basically not change. This allows the phase change process to continue substantially uninhibited, thereby improving the heat dissipation efficiency. Similarly, when the heat dissipating medium undergoes an exothermic phase change from gas phase to liquid phase, the gas pressure in the flow channel 11 decreases and is less than the external gas pressure, which in turn causes at least the expansion chamber 112 of the main unit 1 to undergo a volume contraction deformation, and the volume expansion of at least the expansion chamber 112 of the main unit 1 will increase the gas pressure in the flow channel 11. That is, the gas pressure in the flow channel 11 is maintained basically unchanged by expanding or contracting the volume of at least the expansion chamber 112 of the main unit 1, and the phase change temperature of the liquid heat dissipating medium will also remain substantially unchanged, thereby allowing the phase change process to continue substantially uninhibited, thereby improving the heat dissipation efficiency.

[0070] In addition, in the second mode, along with the heat absorption and release phase change of the heat dissipation medium, a gas-liquid two-phase flow is formed in the flow channel 11, and only a small part of the gas phase medium will be mixed into the liquid phase medium to form a gas column. Most of the gas phase medium will cause the gas pressure in the flow channel 11 to increase, causing at least the expansion chamber 112 of the main unit 1 to expand in volume, so that the gas phase medium is accommodated by the air chamber formed by the volume expansion of at least the expansion chamber 112 of the main unit 1. Therefore, the heat dissipation medium flowing through the actuator unit still essentially remains in the liquid phase, and the actuation efficiency of the actuator unit will not be greatly reduced due to the mixing of a large amount of gas phase medium, thereby improving the stability and reliability of the heat dissipation module.

[0071] Preferably, the heat dissipation fluid is a mixed heat dissipation fluid. By designing the composition of the mixed heat dissipation fluid, it has higher feasibility in matching the phase change heat cooling system with fluctuating heat load or heat flux density. By regulating the proportion of each component in the mixed heat dissipation fluid composed of several easily available base liquids and dispersion liquids, a good matching effect can be achieved, and the phase change process can be actively controlled.

[0072] For example, by designing the composition of the mixed heat dissipation fluid and controlling the proportion of each component in the mixed heat dissipation fluid, it can be achieved that when the heat load of the heat source is small, the actuating unit causes the mixed liquid heat dissipation fluid to circulate in the flow channel 11, and quickly and evenly disperses the heat of the concentrated heat source in contact with the main unit 1 to the entire main unit 1, thereby reducing the temperature of the heat source. As the heat load increases, part of the dispersed liquid in the mixed heat dissipation fluid participates in the phase change heat transfer. As the heat load further increases, more or all of the dispersed liquid participates in the phase change. When the heat load continues to increase, even part of the base liquid participates in the phase change heat transfer. However, there is always part of the base liquid that does not participate in the phase change heat transfer when the heat load and the heat dissipation efficiency of the heat dissipation module are balanced. On the one hand, it can ensure that there is always liquid heat dissipation medium in the flow channel 11 to avoid local evaporation. On the other hand, most of the heat dissipation medium converted into gas phase is accommodated in the air chamber formed by the volume expansion of at least the expansion chamber 112 of the main unit 1, which is equivalent to reducing the amount of gas in the gas-liquid two-phase flow flowing through the actuating unit arranged at the far end. The inlet end of the actuating unit has a continuous and stable high negative pressure, and the actuating efficiency of the actuating unit will not be greatly reduced due to the mixing of a large amount of gas phase heat dissipation medium, thereby avoiding the phase change heat cooling system reaching the flow limit and causing evaporation or liquid plugging, thereby improving the stability and reliability of the heat dissipation module.

[0073] Of course, it is also possible to design the composition of the mixed heat dissipation fluid and control the proportion of each component in the mixed heat dissipation fluid to achieve the situation where only the dispersion liquid undergoes phase change while the base liquid does not undergo phase change from beginning to end in response to fluctuations in heat load. This will not be elaborated here.

[0074] Embodiment 2: The difference between Embodiment 2 and Embodiment 1 is that the portion of the flow channel 11 other than the expansion chamber 112 is the main body section 111, which means that the expansion chamber 112 and the main body section 111 are both part of the flow channel 11, and the main body section 111 is connected to the expansion chamber 112, and the cross-sectional area of ​​the expansion chamber 112 is larger than the cross-sectional area of ​​the main body section 111; so that the expansion chamber 112 can accommodate more gas-phase heat dissipation medium without hindering the normal flow of the liquid-phase heat dissipation medium.

[0075] The lateral width of the expansion chamber 112 in the lateral direction perpendicular to the flow direction of the heat dissipation medium therein is W1, and the lateral width of the main section 111 in the lateral direction perpendicular to the flow direction of the heat dissipation medium therein is W2, W1>W2; the lateral direction is perpendicular to the thickness direction of the main unit 1, and the lateral width of the expansion chamber 112 is greater than the lateral width of the main section 111 of the flow channel 11. In this way, the expansion chamber 112 has a larger lateral width and a larger span than other parts of the flow channel 11, and is prone to deformation.

[0076] Embodiment 3, Embodiment 3 differs from Embodiment 1 or 2 in that: the main unit 1 has a heat absorbing section 12 for absorbing heat from a heat source, that is, the area where the main unit 1 contacts the heat source is defined as the heat absorbing section 12, and the flow channel 11 extends to the heat absorbing section 12; the heat dissipating medium at the outlet end of the actuating unit flows into the heat absorbing section 12 along the flow channel 11, and after the heat dissipating medium absorbs heat from the heat source in the heat absorbing section 12, it flows out of the outlet end of the heat absorbing section 12 along the flow channel 11, and then the heat dissipating medium reaches the expansion chamber 112, and finally returns to the inlet end of the actuating unit along the flow channel 11, thereby forming a cycle;

[0077] The actuating unit is arranged away from the heat absorbing section 12, and the position of the expansion chamber 112 is arranged so that the heat dissipating medium passes through the expansion chamber 112 during the process of flowing from the heat absorbing section 12 to the actuating unit along the flow channel 11, that is, the expansion chamber 112 is arranged on the flow channel 11 between the heat dissipating medium flowing from the heat absorbing section 12 to the actuating unit, so that when the heat dissipating medium absorbs heat and may start phase change, the expansion chamber 112 can provide sufficient space to accommodate the heat dissipating medium in the gas phase in time;

[0078] It is worth noting that an expansion chamber 112 may also be provided on the flow channel 11 where the heat dissipating medium flows from the actuating unit to the heat absorbing section 12;

[0079] Furthermore, in the flow direction of the heat dissipation medium, the distance between the expansion chamber 112 and the heat absorption section 12 may be but is not limited to being smaller than the distance between the expansion chamber 112 and the actuation unit, so that the expansion chamber 112 is closer to the heat absorption section 12 than the actuation unit.

[0080] Embodiment 4, as Figure 6 As shown, an electronic device adopts the heat dissipation module in the above embodiment, and the heat dissipation module is arranged on the inner wall of the electronic device housing 7 and forms heat exchange with the heating element 9 of the electronic device. The heat of the heating element 9 is quickly and evenly dispersed to the housing of the electronic device through the heat dissipation module, accelerating the heat exchange between the housing and the external environment and improving the heat dissipation efficiency.

[0081] Embodiment 5, as Figure 7As shown, an electronic device protective cover adopts the heat dissipation module in the above embodiment, the heat dissipation module is attached to the inner wall of the protective cover 8 facing the electronic device, and forms heat exchange with the heating area of ​​the electronic device housing 7. The heat accumulated in the electronic device housing 7 is quickly and evenly dispersed to the protective cover 8 through the heat dissipation module, accelerating the heat exchange between the protective cover 8 and the external environment, and improving the heat dissipation efficiency.

[0082] The above-mentioned ideal embodiments of the present invention are for inspiration. Through the above-mentioned description, relevant staff can make various changes and modifications without departing from the technical idea of ​​the present invention. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A heat dissipation module, comprising a main unit (1) and at least one actuating unit, wherein the main unit (1) has a flow channel (11) inside for a heat dissipation medium to flow, the flow channel (11) and the actuating unit cooperate to form a closed circulation flow path, and the actuating unit is used to provide power for the circulation of the heat dissipation medium in the circulation flow path, characterized in that: The heat dissipation module has a first mode in which the heat dissipation medium does not undergo phase change and a second mode in which the heat dissipation medium undergoes phase change; A portion of the flow channel (11) is formed as an expansion chamber (112), and there is at least one expansion chamber (112); at least a portion of the main body unit (1) opposite to the expansion chamber (112) is formed as a flexible portion, and the flexible portion can deform to expand or contract the volume of the flow channel (11) as the gas pressure in the flow channel (11) changes; In the first mode, the expansion chamber (112) does not hinder the directional circulation flow of the liquid-phase heat dissipating medium; In the second mode, when the heat dissipating medium undergoes an endothermic phase change from a liquid phase to a gas phase, the gas pressure in the flow channel (11) increases and becomes greater than the external gas pressure, which causes at least the expansion chamber (112) of the main unit (1) to undergo a volume expansion deformation, and the volume expansion of at least the expansion chamber (112) of the main unit (1) causes the gas pressure in the flow channel (11) to decrease; when the heat dissipating medium undergoes an exothermic phase change from a gas phase to a liquid phase, the gas pressure in the flow channel (11) decreases and becomes less than the external gas pressure, which causes at least the expansion chamber (112) of the main unit (1) to undergo a volume contraction deformation, and the volume contraction of at least the expansion chamber (112) of the main unit (1) causes the gas pressure in the flow channel (11) to increase; In the second mode, the gas phase working medium is contained in a gas chamber formed by the volume expansion of at least the expansion chamber (112) of the main unit (1).

2. The heat dissipation module according to claim 1, characterized in that: The portion of the flow channel (11) other than the expansion chamber (112) is a main body section (111), the main body section (111) is in communication with the expansion chamber (112), and the cross-sectional area of ​​the expansion chamber (112) is greater than the cross-sectional area of ​​the main body section (111).

3. The heat dissipation module according to claim 2, characterized in that: The expansion chamber (112) has a transverse width W1 in a transverse direction perpendicular to the flow direction of the heat dissipating medium therein, and the main body section (111) has a transverse width W2 in a transverse direction perpendicular to the flow direction of the heat dissipating medium therein, W1>W2.

4. The heat dissipation module according to claim 1, characterized in that: The main unit (1) has a heat absorbing section (12) for absorbing heat from a heat source, the flow channel (11) extends to the heat absorbing section (12), and the position of the expansion chamber (112) is arranged so that the heat dissipating medium passes through the expansion chamber (112) during the process of flowing from the heat absorbing section (12) to the actuating unit along the flow channel (11).

5. The heat dissipation module according to claim 1, characterized in that: The heat dissipation medium in the flow channel (11) is of a single type.

6. The heat dissipation module according to claim 5, characterized in that: The heat dissipation medium is fluorinated liquid or silicone oil.

7. The heat dissipation module according to claim 1, characterized in that: The heat dissipation medium in the flow channel (11) is a mixed heat dissipation medium, which contains at least one base liquid and at least one dispersion liquid; Under the same gas pressure, all base liquids and all dispersed liquids constituting the mixed heat dissipation medium have different saturation temperatures.

8. The heat dissipation module according to claim 7, characterized in that: All base liquids and all dispersed liquids constituting the mixed heat dissipation medium are immiscible with each other.

9. The heat dissipation module according to claim 7, characterized in that: The base liquid is water, methanol, ethanol or quicksand oil, and the dispersion liquid is fluorinated liquid or silicone oil.

10. The heat dissipation module according to claim 7, characterized in that: Under the same gas pressure, the saturation temperature of any base liquid is greater than the saturation temperature of the dispersion liquid, and there is always a part of the base liquid that does not participate in the phase change heat.

11. The heat dissipation module according to any one of claims 1 to 10, characterized in that: The actuating unit comprises an actuating element (2) and a containing cavity (3) arranged inside the main body unit (1); Both sides of the chamber (3) are in communication with the flow channel (11), and an inlet check valve (4) and an outlet check valve (5) are respectively provided on both sides of the chamber (3); the inlet check valve (4) allows the heat dissipation medium to flow from the flow channel (11) to the chamber (3), and the outlet check valve (5) allows the heat dissipation medium to flow from the chamber (3) to the flow channel (11); and the actuating element (2) is arranged in an area outside the main unit (1) opposite to the chamber (3), and is used to cause the chamber (3) to produce a volume change.

12. The heat dissipation module according to any one of claims 1 to 10, characterized in that: The actuating unit is a fluid pump (6); the exterior of the main unit (1) has at least one liquid inlet and at least one liquid outlet connected to the flow channel (11); the liquid inlet is connected to the fluid outlet of the fluid pump (6); the liquid outlet is connected to the fluid inlet of the fluid pump (6); the fluid pump (6) provides power for the unidirectional circulation of the heat dissipating medium in the circulation flow path.

13. The heat dissipation module according to any one of claims 1 to 10, characterized in that: The main body unit (1) is composed of at least two layers of film materials, and all the film materials are stacked and sealed together to form at least one closed space, and the closed space constitutes the flow channel (11).

14. The heat dissipation module according to claim 13, characterized in that: The main body unit (1) comprises an upper membrane material (1-1), an intermediate membrane material (1-2) and a lower membrane material (1-3) which are stacked in sequence along the thickness direction thereof; a gap structure is provided on the intermediate membrane material (1-2); the gap structure is a groove portion and / or a hole portion penetrating the intermediate membrane material (1-2); the upper membrane material (1-1) and the lower membrane material (1-3) cover the gap structure to form the flow channel (11).

15. The heat dissipation module according to claim 14, characterized in that: The material constituting the upper membrane material (1-1), the middle membrane material (1-2) and the lower membrane material (1-3) is at least one of a polymer material, a metal material or a functional material composited with a polymer material and a metal material.

16. The heat dissipation module according to claim 13, characterized in that: The main body unit (1) is formed in a patch shape with a thickness of 0.01 mm to 2 mm, and the equivalent diameter of the flow channel (11) is 10 μm to 1 mm.

17. An electronic device, characterized in that: A heat dissipation module comprising any one of claims 1-16.

18. An electronic equipment protective cover, characterized in that: A heat dissipation module comprising any one of claims 1-16.

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