Dustproof and moistureproof flexible driving heat dissipation device

Abstract

The invention discloses a dustproof and moistureproof flexible driving heat dissipation device which comprises a mounting base, a heat dissipation cover plate, a driving arm and a driving connecting rod, heat dissipation holes are formed in the mounting base, the heat dissipation cover plate is used for covering or opening the heat dissipation holes, and the mounting base is rotationally connected with the heat dissipation cover plate through at least two rotary connecting structures to form a parallelogram structure. The mounting base is in transmission connection with the heat dissipation cover plate through a U-shaped driving arm, one end of the driving arm is fixedly connected with the mounting base, and the other end of the driving arm is fixedly connected with a driving connecting rod. According to the invention, illumination and heat can drive the CNT-Nafion / PE double-layer driver to deform and enable the heat dissipation holes to be opened or closed, and the projection of the heat dissipation cover plate on the mounting base when the heat dissipation cover plate is opened and the projection of the heat dissipation cover plate on the mounting base when the heat dissipation cover plate is closed can completely cover the heat dissipation holes. A macroscopic large-amplitude bending stroke can be generated by using extremely small temperature change, and the opening degree requirement of opening of a heat dissipation channel is met.

Description

Technical Field

[0001] This invention relates to the field of thermal management and flexible actuator technology, and more specifically to a dustproof and moisture-proof flexible actuator heat dissipation device. Background Technology

[0002] With the rapid development of electronic information technology, the integration and power density of electronic devices (such as outdoor communication cabinets, photovoltaic junction boxes, and high-power computing devices) are constantly increasing, and heat dissipation has become a key factor restricting their performance and lifespan. Currently, the most common heat dissipation method is to open ventilation holes or louvers on the device casing, utilizing natural convection or forced air cooling to remove heat. However, open heat dissipation structures present an inherent contradiction between "heat dissipation" and "protection": to improve heat dissipation efficiency, the opening area needs to be maximized; but long-term open holes are prone to dust accumulation, moisture intrusion, and even insect entry, which can lead to short circuits or corrosion, seriously affecting the reliability of the equipment.

[0003] To resolve the aforementioned contradictions, the following two solutions are typically adopted in existing technologies:

[0004] One approach is to use fixed dust filters or labyrinthine air ducts. While this method can block foreign objects to some extent, it greatly increases flow resistance, reduces heat dissipation efficiency, and cannot dynamically adjust according to equipment temperature. Secondly, an active opening and closing mechanism can be used, such as a motor, electromagnet, or shape memory alloy spring to drive the opening and closing of the louvers. When a temperature rise is detected, the controller drives the motor to open the louvers. However, this active system has a complex structure and requires additional temperature sensors, control circuits, and power supplies. This not only increases the cost and size of the system but also makes it susceptible to failure in the event of a power outage or sensor malfunction, resulting in high maintenance costs.

[0005] In recent years, flexible smart materials based on external stimuli (such as light, heat, and electricity) (such as electro-actuated polymers and photothermal responsive composite materials) have received widespread attention in the field of biomimetic actuation due to their advantages such as passive actuation, light weight, and fast response.

[0006] However, directly applying sheet-like smart materials to heat sinks still faces challenges: (1) Limited output displacement: The traditional cantilever beam drive structure has a small end displacement, which makes it difficult to drive a large-opening heat dissipation channel and results in insufficient ventilation. (2) Insufficient mechanical properties: Flexible materials have low stiffness under high temperature or large deformation, making it difficult to stably support heavy cover plates or resist external wind pressure; (3) Low structural integration: Existing designs often lack effective mechanical amplification mechanisms, resulting in low energy conversion efficiency and slow operation.

[0007] Therefore, there is an urgent need to develop an adaptive heat dissipation device that is simple in structure, requires no external sensors or complex circuits, can autonomously adjust the opening and closing angle according to environmental changes, and has a large driving stroke and structural stability. Summary of the Invention

[0008] The technical problem to be solved by the present invention is how to provide an adaptive heat dissipation device that is dustproof and moistureproof.

[0009] This invention solves the above-mentioned technical problems through the following technical means: a dustproof and moisture-proof flexible driven heat dissipation device, comprising a mounting base, a heat dissipation cover, a drive arm, and a drive connecting rod. The mounting base has heat dissipation holes, and the heat dissipation cover is used to cover or open the heat dissipation holes. The mounting base is rotatably connected to the heat dissipation cover through at least two rotating connection structures to form a parallelogram structure. The mounting base is driven by the U-shaped drive arm, which is connected to the heat dissipation cover. One end of the drive arm is fixedly connected to the mounting base, and the other end is fixedly connected to the drive connecting rod. The end of the heat dissipation cover facing the mounting base has a sliding fit that is adapted to and slidably engaged with the drive connecting rod. The limiting slide is positioned so that the PE side of the drive arm is away from the heat dissipation cover. When the set temperature is reached, it can drive the drive arm to deform and cause the heat dissipation holes to open or close. When the heat dissipation cover is open, the projection on the mounting base can completely cover the heat dissipation holes. The mounting base is also provided with a groove, in which there is a moisture-absorbing expansion block and a limiting lock tongue connected to the moisture-absorbing expansion block. When the set humidity is reached, the moisture-absorbing expansion block can expand and drive the limiting lock tongue to extend into the plane of the rotating connection structure and limit the rotating connection structure. The force of humidity on the drive arm is greater than the force of temperature on the drive arm.

[0010] As a preferred technical solution, the drive arm is a CNT-Nafion / PE dual-layer drive, an AB-Nafion / PE drive, or an MXene / PE drive.

[0011] As a preferred technical solution, the drive arm includes a first transverse connecting section, a second transverse connecting section, and at least one longitudinal connecting section. The first transverse connecting section is fixedly connected to the second transverse connecting section through the longitudinal connecting section. Both the first transverse connecting section and the second transverse connecting section are arranged along the length direction of the heat dissipation cover, and the longitudinal connecting section is arranged along the width direction of the heat dissipation cover.

[0012] As a preferred technical solution, the dustproof and heat dissipation device is located on the top of the electronic device housing, the top wall of the electronic device housing forms a mounting base, and the size of the heat dissipation cover is larger than the size of the heat dissipation holes.

[0013] As a preferred technical solution, the rotary connection structure includes a support rod, with two support rods respectively located on opposite sides of the heat dissipation hole. The bottom end of the support rod is rotatably connected to the mounting base via a rotating shaft, and the top end of the support rod is rotatably connected to the lower surface of the heat dissipation cover via an upper fixing block.

[0014] As a preferred technical solution, the dustproof and heat dissipation device is located around the periphery of the electronic device housing, and the side wall of the electronic device housing forms a mounting base.

[0015] As a preferred technical solution, the rotary connection structure includes hinges, with both hinges located above the mounting holes.

[0016] As a preferred technical solution, the CNT-Nafion / PE dual-layer actuator includes an active layer and a passive layer, wherein the active layer is a PE composite film and the passive layer is a CNT-Nafion film.

[0017] As a preferred technical solution, the heat dissipation holes are located at the center of the mounting base.

[0018] As a preferred technical solution, the heat dissipation cover has an elliptical streamlined structure, and a sealing ring or sealing gasket is provided at the end facing the mounting base.

[0019] As a preferred technical solution, two rectangular frames are fixedly connected to the bottom of the heat dissipation cover, and a limiting groove is formed at the center of each of the two rectangular frames.

[0020] As a preferred technical solution, the heat dissipation cover is partially opened when the internal temperature of the electronic device reaches 35°C to 40°C; when the internal temperature of the electronic device reaches 45°C or above, the heat dissipation cover is fully opened; and the humidity is set to an ambient relative humidity of 75%RH to 85%RH.

[0021] The beneficial effects of this invention are as follows: (1) In this invention, by setting the drive arm to a U-shaped structure, a more uniform driving force can be provided. Compared with the traditional single-piece cantilever beam structure, the output force is increased by more than 2 times while maintaining flexibility, which can effectively overcome the gravity of the heat dissipation cover and the external micro wind pressure; by the cooperation of the drive connecting rod and the limiting slide groove, the compound motion at the end of the driver is decomposed, and only the vertical thrust is transmitted, while the horizontal direction slides freely, which greatly reduces energy loss; by the parallelogram structure formed by the heat dissipation cover, the rotating connection structure and the mounting base, it is easy to deform, which effectively avoids the cover jamming or tilting, and ensures that a small driving force is used to drive the large opening of the heat dissipation cover; by The drive arm is configured as a CNT-Nafion / PE dual-layer actuator, requiring no external drive source, motor, or complex control circuitry. Utilizing the difference in thermal expansion coefficients of the dual-layer materials, the "planar expansion and contraction strain" at the microscopic level is transformed into "vertical bending displacement" at the macroscopic level. It can generate a large bending stroke visible to the naked eye with minimal temperature changes, meeting the opening requirements of the heat dissipation channel. At the same time, heat dissipation is only activated when the heat reaches a set value. Compared to a normally open filter structure, it can provide dust prevention when not in use. Through the setting of moisture-absorbing expansion blocks and limiting locking tongues, the heat dissipation cover can be closed under high humidity conditions, achieving moisture prevention.

[0022] (2) In this invention, the parallelogram structure design can present a large opening area, significantly reduce air flow resistance, and improve the heat dissipation efficiency of natural convection or forced air cooling. In the non-working state, the heat dissipation cover is tightly attached to the base to form a closed structure, which effectively prevents dust, rainwater, insects and other substances from entering the device and extends the service life of the electronic equipment. Attached Figure Description

[0023] Figure 1 This is an exploded structural diagram of the dustproof and heat dissipation device provided in Embodiment 1 of the present invention; Figure 2 This is a side view of the heat dissipation cover in the heat dissipation state provided in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the dustproof state of the heat dissipation cover provided in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the heat dissipation state of the heat dissipation cover provided in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the airflow direction of the dustproof heat dissipation device provided in Embodiment 1 of the present invention; Figure 6 This is a schematic diagram of the driving principle of the CNT-Nafion / PE dual-layer driver provided in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the CNT-Nafion / PE dual-layer driver structure provided in Embodiment 1 of the present invention; Figure 8 This is a schematic diagram showing the changes of the CNT-Nafion / PE dual-layer driver provided in Embodiment 1 of the present invention at different temperatures; Figure 9 This is a schematic diagram of the dustproof state of the heat dissipation cover provided in Embodiment 3 of the present invention; Figure 10 This is a schematic diagram of the heat dissipation state of the heat dissipation cover provided in Embodiment 3 of the present invention; Figure 11 This is a schematic diagram of the heat dissipation state of the heat dissipation cover provided in Embodiment 4 of the present invention; Figure 12 This is a three-dimensional structural diagram of the heat dissipation cover provided in Embodiment 4 of the present invention; Figure 13 This is a schematic diagram of the dustproof state of the heat dissipation cover provided in Embodiment 4 of the present invention; Figure 14 This is a schematic diagram of the moisture-absorbing expansion block and the limiting locking tongue provided in Embodiment 5 of the present invention; Reference numerals: 1. Heat dissipation cover; 2. Upper fixing block; 3. Support connecting rod; 4. Drive connecting rod; 5. Mounting base; 51. Heat dissipation hole; 6. Root fixing block; 7. Drive arm; 71. First transverse connecting section; 72. Second transverse connecting section; 73. Longitudinal connecting section; 8. Limiting slide groove; 9. Groove; 10. Moisture-absorbing expansion block; 11. Limiting locking tongue. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1 See Figure 1 A dustproof and moisture-proof flexible driven heat dissipation device includes a mounting base 5, a rotating connection structure, a heat dissipation cover 1, a drive arm 7, a drive connecting rod 4, and a limiting slide groove 8. The heat dissipation cover 1 is rotatably connected to the heat dissipation cover 1 through at least one rotating connection structure. The mounting base 5 is driven to the heat dissipation cover 1 through the drive arm 7. One end of the drive arm 7 is fixedly connected to the mounting base 5, and the other end of the drive arm 7 is fixedly connected to the drive connecting rod 4. The end of the heat dissipation cover 1 facing the mounting base 5 is provided with a limiting slide groove 8 that matches the drive connecting rod 4. The drive connecting rod 4 slides in cooperation with the limiting slide groove 8. The drive arm 7 is made of a flexible intelligent composite material that is sensitive to external stimuli, such as temperature or light.

[0026] See Figure 6 In this embodiment, the driving arm 7 is a CNT-Nafion / PE (carbon nanotube-Nafion / polyethylene composite material) double-layer actuator. The CNT-Nafion / PE double-layer actuator includes an active layer and a passive layer. The active layer is a PE (polyethylene) composite film with high photothermal conversion efficiency, and the passive layer is a CNT-Nafion film. The PE side of the active layer, i.e., the CNT-Nafion / PE double-layer actuator, is set away from the heat dissipation cover plate 1, and the CNT-Nafion side of the passive layer, i.e., the CNT-Nafion side of the CNT-Nafion / PE double-layer actuator, is set towards the heat dissipation cover plate 1. The active layer and the passive layer have different coefficients of thermal expansion or swelling coefficients. Depending on different temperatures or light irradiation, the driving arm 7 exhibits different degrees of bending, thereby achieving adaptive adjustment according to temperature.

[0027] In this embodiment, the drive arm 7 can also be an AB-Nafion / PE actuator, or an MXene / PE actuator, or a graphene / elastomer bilayer composite structure made of graphene. Using aniline black dye (AB) instead of CNT as a photothermal conversion agent can prepare AB-Nafion / PE actuators; MXene / PE actuators can be made using the excellent photothermal conversion efficiency and thermal conductivity of two-dimensional transition metal carbon / nitride (MXene); or bilayer composite structures such as graphene / elastomers can be made using graphene.

[0028] The active layer, i.e. the photothermal conversion layer, can be selected from aniline black-doped Nafion (AB-Nafion), MXene nanosheets, or reduced graphene oxide (rGO). The passive layer, i.e. the base layer, can be made of polyethylene (PE), polydimethylsiloxane (PDMS), or polyvinylidene fluoride (PVDF). During preparation, the active and passive layers are composited using processes such as solution casting, spin coating, or physical bonding, and then cut into a U-shaped structure along the direction of maximum thermal expansion of the material. All of the above materials work by utilizing the photothermal conversion effect and the principle of interlayer thermal expansion / contraction mismatch: among them, the AB-Nafion / PE system has both low cost and excellent humidity response characteristics, namely automatic closure in high humidity; the MXene / PE system has a photothermal response speed in the order of seconds; and the graphene / elastomer system has a large bending deformation range and weather resistance, which can be selected according to the actual application scenario's requirements for response speed or environmental adaptability.

[0029] See Figure 7 , Figure 8The length of the drive arm 7 is 40-80mm, the width is 5-10mm, and the overall thickness is about 50-200μm. The excellent photothermal conversion performance of the polyethylene (PE) composite film material enables the drive arm 7 to respond quickly within 5-10 seconds and generate a large bending curvature when exposed to simulated sunlight (100mW / cm²).

[0030] It should be noted that when the light intensity increases or the ambient temperature rises, the CNT-Nafion / PE dual-layer driver absorbs energy and generates non-uniform thermal expansion, causing the CNT-Nafion / PE dual-layer driver to bend towards the CNT-Nafion side. This drives the heat sink cover 1 to rotate relative to the mounting base 5, forming a heat dissipation channel between the heat sink cover 1 and the mounting base 5. Here, "increased light intensity" refers to the light intensity reaching a preset value, such as 50mW / cm², and "rising ambient temperature" refers to the temperature reaching a preset value, such as 30℃.

[0031] In this embodiment, the length of the drive arm 7 is 40-80mm, the width is 5-10mm, and the overall thickness is about 50-200μm. The driving force of the drive arm 7 is greater than the weight of the heat dissipation cover 1, thereby ensuring that the drive arm 7 can drive the heat dissipation cover 1 to open. In this embodiment, the length of the heat dissipation cover 1 is 120-140mm, the width is 50-80mm, and the weight is less than or equal to 40g.

[0032] See Figure 4 , Figure 5 The mounting base 5 has heat dissipation holes 51. In this embodiment, the heat dissipation holes 51 are located at the center of the mounting base 1, but they can also be located elsewhere. The heat dissipation cover 1 can completely cover the heat dissipation holes 51 in both the projected and closed states of the heat dissipation state. In the heat dissipation state, the projected size of the heat dissipation cover 1 completely covers the heat dissipation holes 51, which can prevent rainwater from entering the heat dissipation holes 51. In the dustproof state, the size of the heat dissipation cover 1 is larger than the heat dissipation holes 51, which can ensure that the heat dissipation cover 1 fits tightly with the mounting base 5. When the heat dissipation cover 1 is in contact with the mounting base 5, the heat dissipation cover 1 is in the closed state. When a heat dissipation channel is formed between the heat dissipation cover 1 and the mounting base 5, the heat dissipation cover 1 is in the heat dissipation state. See Figure 3 , Figure 4 The heat dissipation cover 1 is located above the mounting base 5, and the size of the heat dissipation cover 1 is larger than the size of the heat dissipation through hole to ensure that it completely covers the heat dissipation through hole in the closed state, so as to play a role in dust prevention and waterproofing. The heat dissipation cover 1 has an elliptical streamlined structure to reduce edge wind resistance. Of course, it can also be rectangular, circular or other shapes. The end of the heat dissipation cover 1 facing the mounting base 5 is provided with a sealing ring or sealing gasket. In this embodiment, taking two rotary connection structures as an example, the heat dissipation cover 1 can form a parallelogram structure with the mounting base 5 through the two rotary connection structures; increasing the number of rotary connection structures can increase the number of parallelograms formed, thereby improving the stability of the connection between the heat dissipation cover 1 and the mounting base 5.

[0033] See Figure 1 The drive arm 7 has a U-shaped structure and includes a first transverse connecting section 71, a second transverse connecting section 72, and at least one longitudinal connecting section 73. In this embodiment, the first transverse connecting section 71 and the second transverse connecting section 72 are both arranged along the length direction of the heat dissipation cover plate 1, and the longitudinal connecting section 73 is arranged along the width direction of the heat dissipation cover plate 1. The first transverse connecting section 71 and the second transverse connecting section 72 are arranged in parallel. In this embodiment, a longitudinal connecting section 73 is provided. The first transverse connecting section 71 is fixedly connected to the second transverse connecting section 72 through the longitudinal connecting section 73. After the first transverse connecting section 71, the second transverse connecting section 72, and the longitudinal connecting section 73 are fixedly connected, a U-shaped structure is formed. Of course, the first transverse connecting section 71, the second transverse connecting section 72, and the longitudinal connecting section 73 can also be prefabricated as an integral structure during manufacturing. By setting the drive arm 7 as a U-shaped structure, the design of the first transverse connecting section 71 and the second transverse connecting section 72 is equivalent to connecting two single-arm cantilever beam drivers in parallel, and the longitudinal driving force is improved through the longitudinal connecting section 73. Compared with the traditional single-strip driver, the U-shaped structure maintains flexibility while increasing the output force by more than 2 times, which can effectively overcome the gravity of the heat dissipation cover 1 and the external micro wind pressure. One end of the drive arm 7, i.e. the open end of the U-shaped structure, is fixedly connected to the mounting base 5. That is, the ends of the first transverse connecting section 71 and the second transverse connecting section 72 that are away from the longitudinal connecting section 73 are fixedly connected to the mounting base 5, providing a reaction force fulcrum for the bending deformation of the drive arm 7. One end of the drive arm 7 is pressed or directly glued to the preset groove of the mounting base 5 by the root fixing block 6. The other end of the drive arm 7, i.e. the closed end of the U-shaped structure, is fixedly connected to the drive connecting rod 4. The drive connecting rod 4 serves as the power output end and is slidably connected to the slide rail in the lower surface of the heat dissipation cover plate 1. In order to eliminate the horizontal displacement difference generated when the drive arm 7 is bent and deformed and to prevent the mechanism from jamming, the lower surface of the heat dissipation cover plate 1 is provided with a limiting slide groove 8 that is adapted to the drive connecting rod 4. The drive connecting rod 4 extends into the limiting slide groove 8 and can slide along the limiting slide groove 8. In this embodiment, two rectangular frames are fixedly connected to the bottom of the heat dissipation cover plate 1, and the center of the rectangular frames forms the limiting slide groove 8. By cooperating with the limiting slide groove 8 and the drive connecting rod 4, the compound motion at the end of the drive arm 7 is decomposed, and only the vertical thrust is transmitted, while the horizontal sliding is free. This greatly reduces energy loss and ensures that even a small driving force can smoothly lift the heat dissipation cover plate 1. The end of the drive connecting rod 4 that extends into the limiting slide groove 8 is redundant, thereby ensuring that the drive connecting rod will not come out of the limiting slide groove 4.

[0034] See Figure 1 , Figure 4 In this embodiment, the rotating connection structure takes the support rod 3 as an example. The support rod 3 is symmetrically arranged on the left and right edges of the heat dissipation hole 51 in the width direction. The mounting base 5 has a slot for the support rod 3 to be inserted. The bottom end of the support rod 3 is rotatably connected to the mounting base 5 through a rotating shaft, so that it can rotate around its axis. The top end of the support rod 3 is rotatably connected to the lower surface of the heat dissipation cover plate 1 through the upper fixing block 2. The upper fixing block 2 is a bearing seat. The two support rods 3, the heat dissipation cover plate 1, and the mounting base 5 form a parallelogram structure, thereby ensuring that the heat dissipation cover plate 1 always maintains a horizontal posture during the lifting and lowering process.

[0035] The dustproof and heat dissipation device in this embodiment can be installed on the electronic device housing. When installed on the electronic device housing, such as an indoor cabinet, for heat dissipation of the indoor cabinet, the dustproof and heat dissipation device is installed on the top of the cabinet, and the top wall of the cabinet forms an installation base 5. Of course, it can also be installed on other main bodies that need heat dissipation, such as outdoor cabinets, photovoltaic module junction boxes, automobiles, etc.

[0036] It should be noted that temperature has a stronger effect on the driver than light. The CNT-Nafion / PE bilayer actuator is essentially a thermally actuated material. The direct physical cause of its deformation is the temperature change inside the material. The mechanism of light irradiation is photothermal conversion. Light does not directly generate force, but rather the photothermal conversion effect occurs through the CNT (carbon nanotube) layer in the material. CNTs efficiently absorb photon energy and convert it into lattice vibration, i.e., heat energy, which causes the local temperature of the material to rise rapidly.

[0037] When sunlight shines on the black CNT layer through the gap between the heat dissipation cover 1 and the mounting base 5, the CNT-Nafion layer exhibits a unique deformation mechanism under light stimulation. The internal moisture evaporates due to the increase in temperature, resulting in volume shrinkage and deformation similar to pseudo-thermal shrinkage. This process is due to the excellent photothermal conversion ability of the CNT component, which converts light energy into heat energy, enabling the surface temperature of the film to rise rapidly within a few seconds, much higher than the ambient temperature. At the same time, the PE layer with a large coefficient of thermal expansion expands under the effect of temperature rise, resulting in a huge difference in interlayer thermal expansion. When the double-layer structure is exposed to light, the photothermal effect of the CNT layer causes the overall temperature to rise. The two material layers produce stress mismatch due to opposite volume changes, ultimately generating a strong driving force and driving the actuator to bend towards the CNT-Nafion side. It should be noted that the CNT-Nafion / PE dual-layer driver in this embodiment is prior art. It can be the CNT-Nafion / PE dual-layer driver in the patent document with patent publication number CN120174998A, or the CNT-Nafion / PE dual-layer driver in the patent document with patent publication number CN119418678A.

[0038] Compared to passive heat transfer that relies on a slow increase in ambient temperature, light radiation acts directly on the surface of the actuator, resulting in a faster response speed (second-level response) and a larger local temperature difference. Therefore, the thermal stress generated by light is stronger than that of passive heat transfer caused by an increase in ambient temperature. The PE (polyethylene) film has an anisotropic coefficient of thermal expansion, and the extension direction of the drive arm 7 is consistent with the direction in which the PE film has the maximum coefficient of thermal expansion.

[0039] Meanwhile, the CNT-Nafion / PE dual-layer driver selected in this embodiment also has excellent humidity response characteristics. When the ambient humidity increases significantly, the CNT-Nafion / PE dual-layer driver, i.e., the drive arm 7, can remain straight, thereby making the heat dissipation cover 1 tightly fit the mounting base 5, keeping the electronic device housing sealed, and preventing external humid air or water from flowing into the device, causing condensation or water accumulation.

[0040] The principle is that the Nafion matrix contains a large number of hydrophilic sulfonic acid groups and nano water channels. When the ambient humidity increases significantly (such as hot and humid weather after rain), the CNT-Nafion layer, i.e. the passive layer, will quickly absorb moisture and swell, while the hydrophobic PE layer, i.e. the active layer, will keep its volume unchanged. This difference in the moisture absorption and expansion coefficient between the layers will generate internal stress, which will cause the drive arm 7 to remain straight.

[0041] Working principle: In this embodiment, the degree of bending of the drive arm 7 and the degree of opening and closing of the heat dissipation cover 1 are positively correlated with the ambient light intensity / temperature, and have stepless adjustment characteristics. When there is low light or low temperature (such as in the early morning, on a cloudy day, or on a rainy day): When the ambient light intensity is below the threshold (e.g., <20mW / cm²) or the temperature is low, the CNT-Nafion / PE dual-layer actuator is in thermal equilibrium and does not generate sufficient thermal stress inside, thus maintaining its initial flat shape. Status: The heat dissipation cover 1 is in a fully closed state, i.e., a dustproof state, under the action of gravity or auxiliary elastic force, which serves to prevent dust and keep the heat out; the auxiliary elastic force here refers to the elastic force of the CNT-Nafion / PE dual-layer driver when it is in the straight state; When there is moderate sunlight (such as in the morning or on a cloudy day): As the light intensity increases, the CNT-Nafion / PE double-layer actuator absorbs light energy and converts it into heat energy, causing the temperature to rise and resulting in slight bending. The heat dissipation cover 1 is partially opened, and the heat dissipation cover 1 is at a small angle or low height to allow for appropriate ventilation and heat dissipation.

[0042] When exposed to strong sunlight or high temperatures (such as at noon): When the light intensity reaches its peak, such as when the light intensity is >80mW / cm²; The PE layer in the CNT-Nafion / PE dual-layer actuator expands to its maximum value when heated, while the CNT-Nafion layer shrinks due to water loss. The stress difference between the two is at its maximum, and the bending curvature of the actuator arm reaches its maximum.

[0043] When the heat dissipation cover 1 is pushed to its maximum opening height, the heat dissipation channel is fully opened, and the heat generated inside the device due to exposure to the sun is quickly removed through natural convection.

[0044] Example 2 The difference between this embodiment and Embodiment 1 is that it provides a method for fabricating a CNT-Nafion / PE dual-layer actuator, including the following steps: S1. Prepare a CNT-Nafion mixed dispersion; The raw materials were a perfluorosulfonic acid resin solution (Nafion, concentration approximately 5 wt.%), an organic solvent N,N-dimethylacetamide (DMAC), and carboxylated single-walled carbon nanotubes (SWCNTs). Nafion solution, DMAC and carboxylated SWCNTs were mixed at a mass ratio of 3:1:0.015 (corresponding to a CNT content of approximately 10 wt.% under dry conditions). The mixture was magnetically stirred (at a speed of about 500 r / min for 5 hours), and then ultrasonically treated in an ice-water bath (power 300 W, frequency 20 kHz for 1 hour) to ensure that the carbon nanotubes were uniformly dispersed in the matrix. Finally, the dispersion was vacuum degassed for about 20 minutes to remove internal bubbles and obtain a uniform CNT-Nafion casting solution. S2. Preparation of CNT-Nafion composite films: The casting solution prepared in step S1 is coated onto a clean glass substrate using either a drop-coating or a blade-coating method. The substrate coated with casting solution was placed on a heating stage at 50°C and heated at a constant temperature for about 5 hours to allow the solvent to evaporate and solidify. After naturally cooling to room temperature, the glass substrate was immersed in deionized water, and the film was automatically detached by the wetting effect of the water, resulting in a CNT-Nafion composite film with a thickness of approximately 20 μm. This film exhibits excellent photothermal conversion efficiency and moisture absorption and expansion characteristics. S3, Double-layer structure composite and molding: A commercial PE (polyethylene) tape with a thickness of approximately 30 μm was selected as the passive layer. Due to the anisotropic coefficient of thermal expansion of PE material (the longitudinal coefficient of thermal expansion is much greater than that of the transverse coefficient), in order to obtain the maximum bending driving force, it is necessary to identify the longitudinal direction (the direction of maximum thermal expansion) of the PE tape. The CNT-Nafion composite film obtained in step S2 is flatly adhered to the adhesive surface of the PE tape, air bubbles are removed and it is compacted to form a CNT-Nafion / PE double-layer driver blank. Using a laser cutter or precision mold, cut the double-layer driver blank into a U-shaped structure. Note: When cutting, the length direction of the two long arms of the U-shaped structure, i.e., the drive arm 7, should be consistent with the longitudinal direction (maximum thermal expansion direction) of the PE tape.

[0045] S4. Driver component assembly: The rigid drive connecting rod 4 is fixedly connected to the closed end (end) of the U-shaped structure; the root fixing block 6 is installed at the open end (root) of the U-shaped structure, thus completing the preparation of the smart material drive component.

[0046] It should be noted that, in this embodiment, in the above-mentioned CNT-Nafion / PE double-layer actuator manufacturing process, except for specific steps that need to be carried out at a set specific temperature, such as the constant temperature heating and curing at 50°C in S2, the remaining operations, such as liquid mixing, double-layer structure composite, cutting and assembly, are all carried out within an ambient temperature range of 18°C-30°C; of course, the operating ambient temperature can also be 18°C, 19°C, 20°C, 21°C, 23°C, 25°C, 28°C or 30°C or other temperature values.

[0047] Example 3 See Figure 9 , Figure 10 The difference between this embodiment and embodiment 1 is that, in this embodiment, the dustproof heat dissipation device is installed on the circumferential wall of the electronic device housing, such as the side wall. The side wall of the electronic device housing forms the mounting base 5. When the heat dissipation cover 1 is in dustproof mode, it is perpendicular to the ground. The length direction of the heat dissipation cover 1 is perpendicular or parallel to the ground.

[0048] Dustproof and heat dissipation devices can be symmetrically arranged on two symmetrical surfaces of the electronic device housing, which can form convection during heat dissipation and improve the heat dissipation effect.

[0049] Example 4 See Figure 11 , Figure 12 , Figure 13 The difference between this embodiment and embodiment 3 is that, in order to improve the rainproof effect when the heat dissipation cover 1 is opened, the rotating connection structure adopts a hinge. The hinge is set on the upper part of the heat dissipation cover 1, thereby realizing the structure of upper hinge and lower opening. When the drive arm 7 drives the heat dissipation cover 1 to rotate relative to the mounting base 5, rainwater will flow down along the cover and cannot flow back into the equipment, which is suitable for outdoor rainy environments.

[0050] Example 5 The difference between this embodiment and embodiment 1 is that the mounting base 5 in this embodiment is provided with a groove 9, and a moisture-absorbing expansion block 10 and a limiting lock tongue 11 are provided in the groove 9. The groove 9 is located at the edge of the slot, with one side open and communicating with the slot. The moisture-absorbing expansion block 10 is SAP (super absorbent polymer) or high-density compressed sponge. The end of the moisture-absorbing expansion block 10 facing the groove 9 is fixedly connected to the limiting lock tongue 11. The plane where the limiting lock tongue 11 is located is above the plane where the top of the support rod 3 is located. Here, the support rod 3 is in a flat state, that is, the heat dissipation cover 1 is in contact with the mounting base 5. The influence of humidity on the drive arm 7 is greater than the influence of temperature on the drive arm 7. Working principle: When in a dry or normal humidity environment: the moisture-absorbing expansion block 10 is in a contracted state and does not expand; the limiting lock tongue 11 is in the initial position and does not interfere with the movement space of the support link 3; at this time, if the outside temperature rises, the drive arm 7 bends, causing the drive connecting rod 4 to slide in the limiting slide groove 8, and the heat dissipation cover 1 opens and dissipates heat. In high humidity environments, such as relative humidity > 80%, water vapor in the air enters the groove 9, and the moisture-absorbing expansion block 10 quickly absorbs water, causing its volume to expand rapidly. Guided by the inner walls of the three sides of the groove 9, the expansion force pushes the limiting locking tongue 11 to pop out and extend above the plane where the support link 3 is located, directly blocking the movement path of the support link 3. At the same time, the humidity will cause the drive arm 7 to remain straight. Even though the internal temperature is high, although the drive arm 7 will bend and try to push the drive connecting rod 4 to slide, the support connecting rod 3 cannot move because its movement path is physically blocked. At the same time, the drive arm 7 will straighten under the influence of humidity, and the heat dissipation cover 1 will be forcibly locked in the closed state. This will ensure that the electronic components in the cabinet are not corroded by condensation or rainwater. When the temperature inside the cabinet reaches the set upper limit temperature value, an alarm can be triggered by the built-in alarm device of the cabinet, so as to allow manual intervention or shutdown.

[0051] In this embodiment, the thermal opening threshold of the drive arm 7 is set to 35℃-40℃. In this embodiment, it can be 35℃, 36℃, 36.5℃, 37℃, 38℃, 39℃, or 40℃. When the internal temperature of the electronic device is within this range and the humidity is normal, the drive arm 7 begins to bend slightly, causing the heat dissipation cover 1 to partially open. When the internal temperature of the electronic device reaches the full opening threshold range, i.e., 45℃-55℃, such as 45℃, 48℃, 50℃, 52℃, or 55℃, the bending curvature of the drive arm reaches its maximum, and the heat dissipation cover 1 is fully opened.

[0052] The high humidity lock threshold of the moisture-absorbing expansion block 10 is set to a relative humidity of 75%RH to 85%RH, such as 75%RH, 78%RH, 80%RH, 82%RH or 85%RH. When in this high humidity environment, regardless of whether the internal temperature of the electronic device reaches the above-mentioned thermal opening threshold, the limit lock tongue 11 remains extended, so that the priority of the moisture-proof lock command is higher than the temperature heat dissipation command, so as to prevent condensate or external rainwater from entering the device.

[0053] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dustproof and moisture-proof flexible driven heat dissipation device, characterized in that, The system includes a mounting base, a heat dissipation cover, a drive arm, and a drive connecting rod. The mounting base has heat dissipation holes, and the heat dissipation cover is used to cover or open these holes. The mounting base is rotatably connected to the heat dissipation cover via at least two rotating connection structures, forming a parallelogram structure. The mounting base is connected to the heat dissipation cover via a U-shaped drive arm. One end of the drive arm is fixedly connected to the mounting base, and the other end is fixedly connected to the drive connecting rod. The end of the heat dissipation cover facing the mounting base has a limiting groove that slidably engages with the drive connecting rod. The PE side of the drive arm is positioned away from the heat dissipation cover. When the set heat level is reached, the drive arm can be driven to deform, causing the heat dissipation holes to open or close. When the heat dissipation cover is open, the projection on the mounting base can completely cover the heat dissipation holes. The mounting base is also provided with a groove, in which a moisture-absorbing expansion block and a limiting lock tongue connected to the moisture-absorbing expansion block are provided. When the set humidity is reached, the moisture-absorbing expansion block can expand and drive the limiting lock tongue to extend into the plane of the rotating connection structure and limit the rotating connection structure. The force of humidity on the drive arm is greater than the force of temperature on the drive arm.

2. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, The drive arm is a CNT-Nafion / PE dual-layer drive, an AB-Nafion / PE drive, or an MXene / PE drive.

3. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, The drive arm includes a first transverse connecting section, a second transverse connecting section, and at least one longitudinal connecting section. The first transverse connecting section is fixedly connected to the second transverse connecting section through the longitudinal connecting section. Both the first transverse connecting section and the second transverse connecting section are arranged along the length direction of the heat dissipation cover, and the longitudinal connecting section is arranged along the width direction of the heat dissipation cover.

4. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, The dustproof and heat dissipation device is located on the top of the electronic device housing. The top wall of the electronic device housing forms a mounting base, and the size of the heat dissipation cover is larger than the size of the heat dissipation holes.

5. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 4, characterized in that, The rotating connection structure includes two support rods, which are respectively located on the opposite sides of the heat dissipation hole. The bottom end of the support rod is rotatably connected to the mounting base via a rotating shaft, and the top end of the support rod is rotatably connected to the lower surface of the heat dissipation cover via an upper fixing block.

6. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, Dustproof and heat dissipation devices are installed around the periphery of the electronic device housing or on the vehicle, with the side wall of the electronic device housing forming a mounting base.

7. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 6, characterized in that, The rotary connection structure includes hinges, with both hinges located above the mounting holes.

8. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 2, characterized in that, The CNT-Nafion / PE dual-layer actuator consists of an active layer and a passive layer. The active layer is a PE composite film, and the passive layer is a CNT-Nafion film.

9. The dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, The heat dissipation cover has an elliptical streamlined structure, and a sealing ring or sealing gasket is provided at the end facing the mounting base. The heat dissipation holes are located at the center of the mounting base. Two rectangular frames are fixedly connected to the bottom of the heat dissipation cover, and a limiting groove is formed at the center of each of the two rectangular frames.

10. A dustproof and moisture-proof flexible drive heat dissipation device according to claim 1, characterized in that, The set heat threshold for the heat dissipation is when the internal temperature of the electronic device reaches 35°C to 40°C, at which point the heat dissipation cover partially opens; when the internal temperature of the electronic device reaches 45°C or above, the heat dissipation cover fully opens; the set humidity is when the ambient relative humidity reaches 75%RH to 85%RH.

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