Separation and storage integrated heat sink structure of electronic equipment

Abstract

The invention discloses an electronic equipment isolation and storage integrated heat sink structure, which belongs to the technical field of heat sink structures, and comprises a metal shell, a heat insulation assembly, a circuit board, a heat capacity block assembly and a bottom plate, the heat insulation assembly, the circuit board and the heat capacity block assembly are sequentially connected and then are fixed in the metal shell through the bottom plate; the heat insulation assembly is used for reducing radiation of external heat to the circuit board; the heat capacity block assembly is used for absorbing heat of the circuit board; the surface of the metal shell is specially treated to reduce the infrared emissivity and absorptivity of the surface of the metal shell. According to the isolation and storage integrated heat sink structure of the electronic equipment, the heat radiation absorption of the micro electronic equipment is reduced, the heat storage of the micro electronic equipment is enhanced, and the dependence on external heat sinks is reduced, so that the purposes of controlling the temperature and saving the space are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat sink structures, and specifically relates to an electronic equipment isolation and storage integrated heat sink structure. Background Art

[0002] There are currently two main problems facing electronic equipment installed in small aircraft: First, the speed of the aircraft platform is getting faster and faster. After the external pneumatic heating platform protective cover, the radiation heat flux density of the inner wall of the cover is getting higher and higher. Infrared thermal radiation has become the main heat source of electronic equipment, and the heat insulation problem needs to be solved urgently; second, with the increase in the integration of equipment in the aircraft, the volume of each electronic equipment is smaller, and the volume of the heat sink allocated is smaller, and the heat storage problem is difficult to solve. Combined with these two problems, the heat dissipation problem of electronic equipment in small aircraft is becoming increasingly prominent. For the heat storage problem, electronic equipment at home and abroad are currently mainly solved in the following ways: 1. Relying on metal mounting parts in the aircraft to dissipate heat. On the one hand, metal parts are used to guide the heat of electronic equipment. On the other hand, the heat capacity of the metal structure can also passively store the heat consumption of electronic equipment when it is working. However, with the increasing integration of various electronic equipment and the increasing power consumption, and the small space in the aircraft, metal structural parts can no longer meet the heat dissipation requirements. 2. Relying on a special passive heat sink module to absorb the heat of the front-end electronic equipment, such as a phase change heat sink module, a liquid metal module, or an integrated heat storage module with a phase change heat sink. The first two methods not only occupy the limited space in the aircraft, but also bring the risk of liquid leakage; the latter method also requires planning the volume of a metal container to encapsulate the phase change part of the integrated heat storage, which is difficult to achieve for small-sized devices. Third, rely on active temperature control devices in the aircraft, such as small spray-type temperature control devices, to spray liquid vapor when the electronic equipment is overheated, so as to achieve the effect of absorbing heat. The problem with this method is that the temperature control device needs to be wired, sensors arranged, and the volume for storing phase change working fluids is provided. The space saving is not obvious, and there is also a reliability risk. The above methods each have their shortcomings, especially the second and third items, which also require planning space in the aircraft for heat dissipation, which cannot be achieved in small-sized aircraft.

[0003] For the insulation problem, the main solutions are: 1. External input insulation, using insulation materials to make protective covers, such as ceramic fiber rigid insulation tiles and ceramic fiber felts, to directly reduce the temperature of the inner wall of the aircraft cover, so as to reduce the heat flux density radiated from the inner wall to the internal electronic equipment. 2. Insulation inside the electronic equipment, using aerogel and fiber insulation felt to add to the insulation area. The insulation performance increases with the thickness and is positively correlated with the space volume. 3. Coating thermal control coatings on the surface of electronic equipment. Currently, it is mainly used in the aerospace field. It has not been used in equipment in small aircraft. At the same time, the existing coating methods are difficult to meet the surface wave transmission requirements of the equipment. The first two insulation methods are mainly focused on increasing the conduction thermal resistance. The latter method cannot take into account the wave transmission requirements, and has not been specifically applied in the field of small aircraft.

[0004] In response to the problems of small heat sink space and large radiated heat in the above-mentioned electronic equipment, an integrated heat sink structure with isolation and storage for electronic equipment is proposed. This structure reduces the thermal radiation absorption of the micro-electronic equipment itself, enhances its own heat storage, and reduces dependence on external heat sinks, so as to achieve the purpose of controlling temperature and saving space. Summary of the invention

[0005] The purpose of the present invention is to address the problems existing in the current phase change heat sink technology solutions and propose an electronic device isolation and storage integrated heat sink structure, which reduces the thermal radiation absorption of the micro-electronic device itself, enhances its own heat storage, and reduces the dependence on external heat sinks, so as to achieve the purpose of controlling temperature and saving space. To achieve the above purpose, the present invention provides the following technical solutions:

[0006] An electronic equipment insulation and storage integrated heat sink structure comprises a metal shell, a heat insulation component, a circuit board, a heat capacity block component and a bottom plate; the heat insulation component, the circuit board and the heat capacity block component are connected in sequence and fixed in the metal shell through the bottom plate; the heat insulation component is used to reduce the external heat radiation to the circuit board; the heat capacity block component is used to absorb the heat of the circuit board; the surface of the metal shell is specially treated to reduce the infrared emissivity and absorptivity of its surface.

[0007] Furthermore, the heat insulation assembly includes a heat insulation cover; first grooves are provided on both sides of the interior of the metal shell; and bosses are provided on both sides of the heat insulation cover for being embedded and fixed in the first grooves on the metal shell.

[0008] Furthermore, a second groove is provided at the bottom of the heat insulation cover; an aerogel is matched and connected in the second groove; and the bottom of the aerogel is in contact with and connected to the circuit board.

[0009] Furthermore, a metal circuit layer is provided on the upper side of the circuit board; the metal circuit layer is in contact with the aerogel; the thickness of the second groove is the sum of the thickness of the aerogel and the thickness of the metal circuit layer, and the second groove also leaves an assembly margin.

[0010] Furthermore, the heat block assembly includes a solid heat block; thermally conductive insulating pads are provided on both the upper and lower sides of the solid heat block; the solid heat block contacts the circuit board through the thermally conductive insulating pad on the upper side; the lower side of the solid heat block contacts the bottom plate through the thermally conductive insulating pad; the bottom plate and the metal shell are detachably connected by screws.

[0011] Furthermore, the outer surface of the metal shell is polished or nickel-plated, and its polishing roughness is less than Ra1.6.

[0012] Furthermore, the outer surface of the heat insulation cover is sprayed with a high temperature resistant and wave-transmitting thermal control coating.

[0013] Furthermore, the solid heat capacity block is a compressible solid phase change heat sink material.

[0014] Furthermore, the heat insulation cover is quartz fiber reinforced ceramics to improve thermal resistance and temperature resistance.

[0015] Furthermore, the thermally conductive insulating pad has a certain toughness and can be compressed.

[0016] The beneficial effects of the present invention are:

[0017] The present invention provides an electronic device insulation and storage integrated heat sink structure, which integrates heat insulation and heat storage on a small-volume device, and uses compressible assembly to improve thermal conductivity and anti-loosening performance. The present invention reduces the infrared emissivity and absorptivity of the outer surface of the device by surface treatment of the heat insulation cover and the metal shell, improves the thermal radiation performance of the module, and reduces heat input; by encapsulating the solid-state phase change heat sink, the circuit board itself is used as a partition, the metal packaging volume of the phase change heat sink is reduced, and the heat capacity space is increased; by low-temperature assembly of the solid-state phase change heat capacity block, thermal expansion at high temperature, and compression with the thermally conductive insulating pads coated on the upper and lower surfaces, thermal resistance is reduced and internal heat conduction efficiency is improved; at the same time, the friction of the thread is increased to improve anti-loosening performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the composition structure of the electronic equipment isolation and storage integrated heat sink structure of the present invention;

[0019] Figure 2 It is a schematic structural diagram of the electronic equipment isolation and storage integrated heat sink structure after assembly of the present invention;

[0020] Figure 3 is an internal view of the metal housing of the present invention;

[0021] Figure 4 is an internal view of the heat shield of the present invention;

[0022] Figure 5 It is a structural schematic diagram of the circuit board in the present invention;

[0023] Figure 6 It is a schematic diagram of heat conduction of the heat sink structure of electronic equipment with integrated storage and isolation according to the present invention;

[0024] Figure 7 This is a simulation analysis diagram of the working condition of the structure of the present invention by the simulation software FloEFD;

[0025] In the attached figure: 1. metal shell; 2. heat insulation cover; 3. aerogel; 4. circuit board; 4.1. metal circuit layer; 5. solid heat capacity block; 6. thermal conductive insulation pad; 7. bottom plate. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0027] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] Example:

[0029] As attached Figures 1 to 6As shown, the present invention discloses an electronic device storage integrated heat sink structure, which includes a metal shell 1, a heat shield 2, an aerogel 3, a circuit board 4, a solid heat block 5, a thermally conductive insulating pad 6 and a bottom plate 7. First grooves are provided on both sides of the inside of the metal shell 1 for interlocking and limiting with the bosses provided on both sides of the heat shield 2. Four M2 threaded holes are evenly provided at the bottom of the metal shell 1, and corresponding threaded holes are also provided on the bottom plate 7. The metal shell 1 and the bottom plate 7 are locked by a screw structure. In this embodiment, the metal shell 1 and the bottom plate 7 are made of brass material. The length and width of the metal shell 1 are 35mm×35mm, and the height is 9mm. The length and width of the bottom plate 7 are 35mm×35mm, and the thickness is 1.5mm. That is, the total length and width of the device are 35mm×35mm, and the height is 10.5mm.

[0030] The outer surface of the metal shell 1 is polished with a roughness of Ra1.6, which reduces the infrared emissivity and absorptivity of the metal surface. After polishing, the emissivity and absorptivity are about 0.2, which can reduce the external heat radiation input.

[0031] The heat shield 2 is 4 mm thick, and a high-temperature resistant and wave-transmitting thermal control coating is sprayed on the outer surface; the circuit board 4 is a composite material, the matrix is ​​a dielectric material, and there is a metal circuit layer 4.1 on the outer surface, preferably a copper-based circuit.

[0032] Preferably, the heat shield 2 is made of quartz fiber reinforced ceramics to improve thermal resistance and temperature resistance.

[0033] Preferably, the thermal control coating is made of organic metal paint which is resistant to high temperature of 400°C, has a wave transmittance of 80%, an infrared emissivity and absorptivity of 0.3, and absorbs little radiation heat flux.

[0034] Preferably, the matrix material of the circuit board 4 is polyimide, which serves as a medium and can increase heat capacity and reduce weight.

[0035] There is a 1.8mm deep second groove in the heat shield 2, and the aerogel 3 with a thickness of 1.5mm is filled at the bottom of the second groove in the heat shield 2, so that a 0.3mm space is left in the second groove. The circuit board 4 with a thickness of 1.5mm is placed under the heat shield 2, and the metal circuit layer 4.1 with a thickness of 0.1-0.3mm is placed in the 0.3mm space left by the heat shield 2 and the aerogel 3. This design is used to ensure that the input heat of the metal circuit layer 4.1 is blocked by the aerogel 3 and the heat shield 2.

[0036] The solid heat capacity block 5 is placed in the metal shell 1 and below the circuit board 4. The solid heat capacity block 5 is covered with thermal insulation pads 6 on the upper and lower sides for heat conduction and adapting to slight changes in the thickness of the solid heat capacity block 5 caused by changes in high and low temperature environments. The bottom plate 7 presses the solid heat capacity block 5 and is fastened to the bottom of the metal shell 1 by 4 countersunk screws, while pressing other components in the metal shell 1. The advantage of this design is that it abandons the requirement of metal packaging shell for phase change materials in current heat sink packaging, reduces weight and saves space.

[0037] Preferably, the solid heat capacitor 5 is made of graphite skeleton alkane-based phase change material, which has a certain compressibility. After being compressed and packaged in the metal shell 1 at low temperature, it expands at high temperature and is pressed against the thermally conductive insulating pads 6 coated on the upper and lower surfaces, thereby reducing thermal resistance and improving internal heat conduction efficiency. In addition, compared with the solid-liquid integrated phase change heat sink, the solid phase change heat sink saves the volume of the metal packaging interlayer and has no risk of leakage.

[0038] After the above components are assembled, the device is installed in a small aircraft. When the aircraft flies at high speed, the protective cover is heated by air, the temperature of the inner wall of the protective cover rises, and the radiant heat flow is continuously input to the device, such as Figure 6 As shown. Affected by the polishing of the metal shell 1 and the low emissivity and low absorptivity of the organic metal paint on the heat insulation cover 2, the radiation heat flow absorbed by the device is reduced, realizing the radiation heat insulation of the device itself. When the absorbed heat is conducted to the metal circuit layer 4.1 on the circuit board 4, it has been blocked and stored by the quartz fiber reinforced ceramic and aerogel 3, and the temperature of the metal circuit layer 4.1 is reduced, realizing the conduction heat insulation of the device itself. Moreover, the excess heat of the metal circuit layer 4.1 will be transferred to the solid heat capacitor 5 through the circuit board 4 and the thermally conductive insulation pad 6, realizing the heat storage of the device itself.

[0039] The simulation software FloEFD was used to analyze the working condition. The temperature of the inner wall of the aircraft shield was set to 500°C, the emissivity was 0.85, the inner wall of the electronic equipment was 5mm away from the inner wall of the shield, and the initial ambient temperature inside the equipment was 50°C. The results are as follows Figure 7 As shown, the metal circuit layer 4.1 in the device only reaches 195.8°C after working for 159s, while the outer surface of the device is 328.7°C. It can be seen that the present invention effectively reduces the external heat flow input, and the heat capacity temperature below is about 179.15°C. It can be seen that its continuous heat storage plays a key role in extending the temperature resistance of the equipment.

[0040] The present embodiment provides an integrated heat sink structure for isolation and storage of electronic equipment. By improving and integrating the existing heat storage architecture of micro-electronic equipment, the heat sink design and packaging method of the equipment are improved, and temperature-resistant thermal control coatings, multi-layer thermal insulation and shell anti-thermal radiation measures are integrated. While maintaining a small volume, the heat radiation input of the equipment is reduced, while the transient heat storage capacity of the equipment is enhanced, and the leakage risk of liquid heat storage materials is eliminated.

[0041] This embodiment also carried out a comparative experiment, using the Figure 7The working conditions are simulated and analyzed. A is the scheme of this embodiment, B is the heat dissipation scheme without thermal control coating and metal shell 1 anti-radiation measures, and the heat sink is a solid phase change heat block; C is the heat dissipation scheme using thermal control coating and metal shell 1 anti-radiation measures, and using equal volume metal heat blocks; D is the heat dissipation scheme without solid heat block 5 and no anti-thermal radiation measures. The differences between the schemes are shown in Table 1, where the emissivity of the quartz fiber reinforced ceramic heat shield 2 without thermal control coating is 0.85, the emissivity of the metal shell 1 without anti-thermal radiation measures is 0.6, the metal heat block and the solid heat block 5 are of equal volume, and the material is 5A06 aluminum alloy.

[0042] Table 1

[0043]

[0044] Except for the control items listed in Table 1, the other components are configured the same as in this embodiment, and the assembly method is the same, and they are placed inside a certain type of seeker. The FloEFD software is used to perform thermal simulation calculations on the four schemes, according to the calculation of the inner wall of the aircraft shield at 500°C, the emissivity of 0.85, the distance from the inner wall of the aircraft shield to the surface of the thermal control coating of the equipment at 5mm, and the initial ambient temperature in the equipment at 50°C. The time when the highest temperature of the working metal circuit layer 4.1 of the equipment reaches 180°C in the four schemes is recorded, and the results are shown in Table 2:

[0045] Table 2 Time required for the maximum temperature of the metal circuit layer to reach 200°C

[0046] First Second C Man Time(s) 164 111 110 81

[0047] As shown in the results in Table 2, it can be seen that the electronic equipment insulation and storage integrated heat sink structure provided in this embodiment has a temperature resistance time increased by about 102.46% compared with the existing micro-aircraft electronic equipment heat dissipation solution (Scheme D). The comparison results of Solutions B, C and D also confirm the effectiveness of the insulation measures and heat storage design in the present invention.

[0048] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An electronic equipment storage integrated heat sink structure, characterized in that: The invention comprises a metal shell (1), a heat insulation component, a circuit board (4), a heat block component and a bottom plate (7); the heat insulation component, the circuit board (4) and the heat block component are connected in sequence and fixed in the metal shell (1) via the bottom plate (7); the heat insulation component is used to reduce the radiation of external heat to the circuit board (4); the heat block component is used to absorb the heat of the circuit board (4); the surface of the metal shell (1) is specially treated to reduce the infrared emissivity and absorptivity of the surface.

2. The electronic equipment heat sink structure with integrated storage and isolation according to claim 1, characterized in that: The heat insulation component comprises a heat insulation cover (2); first grooves are provided on both sides of the interior of the metal shell (1); and bosses are provided on both sides of the heat insulation cover (2) for being embedded and fixed in the first grooves on the metal shell (1).

3. The electronic equipment heat sink structure with integrated storage and isolation according to claim 2, characterized in that: The bottom of the heat insulation cover (2) is provided with a second groove; the aerogel (3) is matched and connected in the second groove; and the bottom of the aerogel (3) is in contact and connected with the circuit board (4).

4. The electronic equipment storage integrated heat sink structure according to claim 3, characterized in that: A metal circuit layer (4.1) is provided on the upper side of the circuit board (4); the metal circuit layer (4.1) is in contact with the aerogel (3); the thickness of the second groove is the sum of the thickness of the aerogel (3) and the thickness of the metal circuit layer (4.1), and the second groove also leaves an assembly margin.

5. The electronic equipment heat sink structure with integrated storage and isolation according to claim 4, characterized in that: The heat capacitor assembly comprises a solid heat capacitor (5); heat-conducting insulating pads (6) are provided on both the upper and lower sides of the solid heat capacitor (5); the solid heat capacitor (5) contacts the circuit board (4) via the heat-conducting insulating pad (6) on the upper side; the lower side of the solid heat capacitor (5) contacts the bottom plate (7) via the heat-conducting insulating pad (6); the bottom plate (7) is detachably connected to the metal shell (1) by screws.

6. The electronic equipment heat sink structure with integrated insulation and storage according to claim 5, characterized in that: The outer surface of the metal shell (1) is polished or nickel-plated, and its polishing roughness is less than Ra1.

6.

7. The electronic equipment heat sink structure with integrated insulation and storage according to claim 6, characterized in that: The outer surface of the heat insulation cover (2) is sprayed with a high-temperature resistant and wave-transmitting heat control coating.

8. The electronic equipment heat sink structure with integrated insulation and storage according to claim 7, characterized in that: The solid heat capacity block (5) is a compressible solid phase-change heat sink material.

9. The electronic equipment heat sink structure with integrated insulation and storage according to claim 8, characterized in that: The heat insulation cover (2) is made of quartz fiber reinforced ceramics and is used to improve thermal resistance and temperature resistance.

10. The electronic equipment storage integrated heat sink structure according to claim 9, characterized in that: The thermally conductive insulating pad (6) has a certain toughness and can be compressed.

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