Heat exchanger and air conditioner

Abstract

The invention discloses a heat exchanger and an air conditioner, relates to the technical field of air conditioners, and aims to solve the problem that a moisture absorption coating in an existing heat exchanger is easy to crack when absorbing water during working. The heat exchanger comprises a plurality of fins, a plurality of heat exchange tubes and a moisture absorption material. And the plurality of heat exchange tubes and the plurality of fins are mounted in a contact manner. The hygroscopic material is at least arranged on the surfaces of the fins. Wherein the moisture absorption material comprises a polymer moisture absorption material, an inorganic moisture absorption material and a binder. The inorganic moisture absorption material and the polymer moisture absorption material are mutually mixed. The binder is mixed with the polymer moisture absorption material and the inorganic moisture absorption material. The heat exchanger is used for conducting heat exchange and wet exchange on airflow passing through the heat exchanger.

Description

Technical Field

[0001] This application relates to the field of air conditioning technology, and more particularly to a heat exchanger and an air conditioner. Background Technology

[0002] As people's demands for home comfort increase, the need for dehumidification products is also growing. Current air conditioners primarily employ dehumidification technologies such as refrigeration dehumidification, rotary adsorption dehumidification, and heat exchanger coating dehumidification.

[0003] Heat exchanger coating technology refers to coating the surface of a heat exchanger with a layer of moisture-absorbing material, which works with the heat exchanger to absorb and release moisture to achieve humidity exchange.

[0004] However, the moisture-absorbing layer coated on the surface of the heat exchanger with moisture-absorbing material in related technologies is prone to cracking during operation. These problems limit the moisture absorption efficiency and service life of the moisture-absorbing heat exchanger. Summary of the Invention

[0005] This application provides a heat exchanger and an air conditioner to solve the problem that the moisture-absorbing coating in existing heat exchangers is prone to cracking when absorbing water during operation.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] On one hand, embodiments of this application provide a heat exchanger including multiple fins, multiple heat exchange tubes, and a moisture-absorbing material. The multiple heat exchange tubes are mounted in contact with the multiple fins. The moisture-absorbing material is disposed at least on the surface of the fins. The moisture-absorbing material includes a polymeric moisture-absorbing material, an inorganic moisture-absorbing material, and a binder. The inorganic moisture-absorbing material is mixed with the polymeric moisture-absorbing material. The binder is mixed with both the polymeric moisture-absorbing material and the inorganic moisture-absorbing material.

[0008] The heat exchanger provided in this application embodiment allows the heat exchange tubes to exchange heat with the airflow passing through them, thereby regulating the temperature. The hygroscopic material on the fin surface allows for the exchange of moisture with the airflow, thus regulating the humidity. Both polymeric and inorganic hygroscopic materials can absorb and release water molecules. Due to its porous structure, the inorganic hygroscopic material does not undergo a volume change after absorbing water. The adhesive ensures that it adheres firmly to the fin surface, achieving the function of humidity regulation. The resulting hygroscopic material retains good strength after absorbing moisture, preventing easy cracking and detachment from the fins, thus greatly extending the lifespan of the heat exchanger's hygroscopic function.

[0009] In some embodiments, the inorganic moisture-absorbing material includes molecular sieves, and / or activated alumina, and / or metal-organic framework materials. Molecular sieves have a porous structure to absorb moisture. Activated alumina has a porous structure to absorb moisture. Metal-organic framework materials have a porous structure to absorb moisture.

[0010] In some embodiments, the binder comprises an aqueous resin and / or an aqueous emulsion. The aqueous resin is bonded to the hygroscopic polymer. The aqueous emulsion is bonded to the hygroscopic polymer.

[0011] In some embodiments, the adhesive comprises one or more of waterborne acrylic emulsions, waterborne polyurethanes, waterborne epoxy resins, or styrene-butadiene latex. And / or, the polymeric moisture-absorbing material comprises one or more of polyvinyl alcohol, sodium polyacrylate, polyacrylic acid, polyethylene glycol, polyvinylamide, polyamide, polylactic acid, polyether polyol, povidone, and polymeric hydrogels.

[0012] In some embodiments, the mass ratio of the inorganic moisture-absorbing material to the polymeric moisture-absorbing material is greater than or equal to 1 / 20, and the mass ratio of the inorganic moisture-absorbing material to the polymeric moisture-absorbing material is less than or equal to 1.

[0013] In some embodiments, the inorganic moisture-absorbing material includes a molecular sieve. The mass ratio of the molecular sieve to the polymeric moisture-absorbing material is greater than or equal to 1 / 10, and the mass ratio of the inorganic moisture-absorbing material to the polymeric moisture-absorbing material is less than or equal to 4 / 10. Alternatively, the mass ratio of the molecular sieve material to the polymeric moisture-absorbing material is greater than or equal to 6 / 10, and the mass ratio of the inorganic moisture-absorbing material to the polymeric moisture-absorbing material is less than or equal to 9 / 10.

[0014] In some embodiments, the mass ratio of the adhesive to the polymeric moisture-absorbing material is greater than or equal to 1 / 5, and the mass ratio of the adhesive to the polymeric moisture-absorbing material is less than or equal to 1.

[0015] In some embodiments, the moisture-absorbing material is also disposed on the surface of the heat exchange tube. And / or, the amount of moisture-absorbing material coated per unit area is greater than or equal to 0.5 g / 100 cm². 2 Furthermore, the amount of moisture-absorbing material applied per unit area is less than or equal to 1.5 g / 100 cm². 2 .

[0016] In some embodiments, the viscosity of the hygroscopic material is greater than or equal to 200 mPa·s and less than or equal to 300 mPa·s.

[0017] On the other hand, embodiments of this application also provide an air conditioner, including a housing and any of the aforementioned heat exchangers. A receiving cavity is formed inside the housing. The housing also has an air inlet and an air outlet communicating with the receiving cavity. The heat exchanger is disposed within the receiving cavity.

[0018] The air conditioner provided in this application embodiment has any of the above-mentioned heat exchangers installed inside, which can achieve the same effect as the method of coating the heat exchanger with moisture-absorbing material in the previous aspect and solve the same technical problem, which will not be repeated here. Attached Figure Description

[0019] Figure 1 A schematic diagram of a centrifuge device provided for related technologies;

[0020] Figure 2 This is a schematic diagram of the structure of an air conditioner provided in an embodiment of this application;

[0021] Figure 3 This is a partial structural schematic diagram of a heat exchanger provided in an embodiment of this application;

[0022] Figure 4 This is one of the schematic diagrams illustrating the method steps for coating a heat exchanger with a moisture-absorbing material according to an embodiment of this application;

[0023] Figure 5 This is a schematic diagram of the structure of the vacuum coating equipment provided in the embodiments of this application;

[0024] Figure 6 A second schematic diagram illustrating the steps of coating a heat exchanger with a moisture-absorbing material according to an embodiment of this application;

[0025] Figure 7 This is one of the schematic diagrams illustrating the steps of a method for degreasing the surface of a heat exchanger to remove oil stains from the surface of the heat exchanger, as provided in an embodiment of this application.

[0026] Figure 8 This is a second schematic diagram illustrating the steps of a method for degreasing the surface of a heat exchanger to remove oil stains, as provided in an embodiment of this application.

[0027] Figure 9 This is one of the schematic diagrams illustrating the steps of a method for curing and drying a moisture-absorbing material on the surface of a heat exchanger, as provided in an embodiment of this application.

[0028] Figure 10 This is a second schematic diagram illustrating the steps of a method for curing and drying the moisture-absorbing material on the surface of a heat exchanger, as provided in an embodiment of this application.

[0029] Figure 11 This is one of the structural schematic diagrams of the moisture-absorbing layer provided in the embodiments of this application;

[0030] Figure 12 A schematic diagram of the chemical equation for the reaction between the polymeric moisture-absorbing material provided in the embodiments of this application and one of the adhesives;

[0031] Figure 13 A schematic diagram of the chemical equation for the reaction between the polymeric hygroscopic material and the crosslinking agent provided in the embodiments of this application;

[0032] Figure 14 A schematic diagram of the chemical equation for the reaction between the polymeric moisture-absorbing material provided in the embodiments of this application and another adhesive;

[0033] Figure 15 This is the second schematic diagram of the structure of the moisture-absorbing layer provided in the embodiments of this application;

[0034] Figure 16 A schematic diagram of the device structure for evaluating water resistance provided in the embodiments of this application;

[0035] Figure 17 The figure shows the results of evaluating the adhesion of the moisture-absorbing layer in the embodiments of this application.

[0036] Figure label:

[0037] 100-Air conditioner; 10-Shell; 101-Receiving cavity; 102-Air inlet; 103-Air outlet; 11-First receiving cavity; 12-Second receiving cavity; 13-Fresh air outlet; 14-First air inlet; 15-Return air outlet; 16-Second air inlet; 20-Heat exchanger; 21-First heat exchanger; 22-Second heat exchanger; 23-Fin; 24-Heat exchange tube; 25-Moisture-absorbing layer; 251-Moisture-absorbing material; 2511-Polymer moisture-absorbing material; 2512-Inorganic moisture-absorbing material; 2513-Adhesive; 2514-Crosslinking agent; 30-Glass water tank; 31-Water; 40-Vacuum coating equipment; 41-Vacuum buffer tank; 42-Water ring vacuum unit; 43-Coating main unit; 200-Centrifugal equipment. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0040] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0041] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this application have the meaning of establishing electrical connection. The specific meaning needs to be understood in conjunction with the context.

[0042] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0043] As people's demands for home comfort increase, many products capable of regulating indoor air humidity have appeared on the market. Among them, a regular air conditioner can improve and maintain indoor air temperature, and when the air conditioner's heat exchanger is equipped with moisture-exchanging components and materials, the air conditioner can also improve and maintain indoor air humidity.

[0044] Generally, a moisture-absorbing material is coated on the surface of the heat exchanger. The moisture-absorbing material, in conjunction with the heat exchanger's energy absorption and release, can absorb and release water molecules, thus enabling the heat exchanger to regulate the humidity in the air.

[0045] In related technologies, moisture-absorbing materials are applied to the surface of heat exchanger fins using methods such as impregnation, spraying, electrostatic spraying, and centrifugation to form a moisture-absorbing layer, thereby achieving the function of regulating humidity.

[0046] Among these methods, the impregnation method involves immersing the heat exchanger in a prepared moisture-absorbing material to form a moisture-absorbing layer of a certain thickness. However, the overall thickness and uniformity of the moisture-absorbing material formed by the impregnation method cannot be guaranteed. Due to gravity, the moisture-absorbing layer will be thicker on the side of the heat exchanger closest to the ground, thus clogging the fins and reducing the heat exchanger's moisture exchange efficiency.

[0047] The spraying method involves using specialized equipment such as spray guns or atomizers to disperse the hygroscopic material into uniform and fine droplets, which are then sprayed onto the surface of the fins. This method allows for a uniform coating of the diluted material without cracks, but it cannot be used on assembled heat exchangers.

[0048] Because the gaps between the fins of the assembled heat exchanger are small, the moisture-absorbing material cannot cover every corner. If the material is sprayed on the fins before assembly, it will change the fin thickness and make the fin dimensions incompatible with the original assembly tools, thus making assembly impossible.

[0049] Electrostatic spraying involves negatively charging a powder of a moisture-absorbing material and placing it in a high-intensity electrostatic field. Under the influence of electrostatic force and the propulsion of a carrier gas, the moisture-absorbing material powder is evenly propelled onto the surface of the heat exchanger, forming a thin, uniform powder layer. This powder layer is then heated to solidify and transform into a film.

[0050] The film layer coated by electrostatic spraying is uniform and crack-free, but the coating equipment is complex and the overall cost is high.

[0051] like Figure 1 As shown, Figure 1 This is a schematic diagram of a centrifugal device for related technologies. When using centrifugal coating, the heat exchanger is first impregnated in a prepared hygroscopic material, and then the impregnated heat exchanger is placed in a centrifugal device 200 to use centrifugal force to remove excess slurry.

[0052] This coating method can coat all angles of the heat exchanger, but it requires the fabrication of complex clamping fixtures. Furthermore, the centrifugal force varies at different distances from the centrifugal center, resulting in varying coating amounts at different locations and uneven distribution of the absorbent material.

[0053] Based on this, such as Figure 2 As shown, Figure 2 This is a schematic diagram of the structure of an air conditioner provided in an embodiment of this application. The application provides an air conditioner 100, which may include a housing 10 and a heat exchanger 20. The surface of the heat exchanger 20 is coated with a moisture-absorbing material 251. Figure 11 The moisture-absorbing material 251 is coated onto the surface of the heat exchanger 20 by a method for coating the heat exchanger 20 with moisture-absorbing material, forming a moisture-absorbing layer 25. Figure 11 ).

[0054] The heat exchanger 20 can be a finned heat exchanger 20.

[0055] Specifically, a receiving cavity 101 is formed inside the housing 10. The housing 10 is also provided with an air inlet 102 and an air outlet 103 communicating with the receiving cavity 101. The heat exchanger 20 is disposed inside the receiving cavity 101.

[0056] Specifically, the heat exchanger 20 may include a first heat exchanger 21 and a second heat exchanger 22. Meanwhile, the housing 10 may have a first receiving cavity 11, a second receiving cavity 12, a fresh air outlet 13, a first air inlet 14, a return air outlet 15, and a second air inlet 16. The first receiving cavity 11 is connected to the first air inlet 14 and the fresh air outlet 13, and the second receiving cavity 12 is connected to the second air inlet 16 and the return air outlet 15. The two receiving cavities may be two relatively isolated chambers. The first heat exchanger 21 may be installed in the first receiving cavity 11, and the second heat exchanger 22 may be installed in the second receiving cavity 12.

[0057] The air inlet 102 includes the first air inlet 14 and the second air inlet 16, and the air outlet includes the fresh air outlet 13 and the return air outlet 15. Thus, both the air inlet 102 and the air outlet 103 can be connected to the heat exchanger 20. When dehumidification and cooling of indoor air are required in summer, the air conditioner 100 can direct fresh air from the outside through the first air inlet 14, through the first heat exchanger 21, to the fresh air outlet 13, and into the room. At this time, the heat exchanger 20 can be in evaporator mode, with a moisture-absorbing layer 25 on its surface. Figure 15 The heat exchanger 20 can cool the fresh air flow and absorb moisture from it, thus pre-cooling and dehumidifying the fresh air. Meanwhile, the return air inside the room...

[0058] The return airflow inside the room can flow through the second air inlet 16, pass through the second heat exchanger 22, and be discharged outdoors from the return air outlet 15. At this time, the second heat exchanger 22 can be in condenser mode, and the heat exchanger 20 with a moisture-absorbing layer 25 on its surface can heat the return airflow and release moisture to increase the humidity of the return airflow.

[0059] Therefore, the heat exchanger 20 can independently control the temperature and humidity of the airflow passing through it, thereby achieving precise regulation of the indoor environment.

[0060] During the above process, since the first heat exchanger 21 is in the evaporator state, the heat released by the moisture-absorbing layer 25 on the surface of the first heat exchanger 21 when absorbing water vapor will be directly absorbed by the refrigerant in the first heat exchanger 21, thus not increasing the temperature of the fresh air flow.

[0061] Similarly, since the second heat exchanger 22 is in condenser mode, the moisture-absorbing layer 25 on the surface of the second heat exchanger 22 can directly absorb the heat released by the refrigerant in the second heat exchanger 22 when releasing water vapor, and will not lower the temperature of the return airflow. Therefore, the process of the heat exchanger 20 regulating humidity will not affect the indoor air temperature.

[0062] When indoor air needs to be humidified and heated in winter, fresh air enters the room through the first air inlet 14, the first heat exchanger 21, and the fresh air outlet 13. At this time, the first heat exchanger 21 can be in condenser mode. The first heat exchanger 21, which has a moisture-absorbing layer 25, can heat the fresh air and release moisture to increase the humidity of the fresh air.

[0063] The indoor return airflow can be discharged outdoors through the second air inlet 16, the second heat exchanger 22, and the return air outlet 15. At this time, the second heat exchanger 22 can be in evaporator mode. The second heat exchanger 22, which has a moisture-absorbing layer 25, can cool the return airflow and absorb moisture in the return airflow to achieve a dehumidification effect.

[0064] During the above process, since the second heat exchanger 22 is in the evaporator state, the heat released by the moisture-absorbing layer 25 on the surface of the second heat exchanger 22 when absorbing water vapor will be directly absorbed by the refrigerant in the second heat exchanger 22, thus not increasing the temperature of the fresh air flow.

[0065] Similarly, since the first heat exchanger 21 is in condenser mode, the moisture-absorbing layer 25 on the surface of the first heat exchanger 21 can directly absorb the heat released by the refrigerant in the first heat exchanger 21 when releasing water vapor, and will not lower the temperature of the return airflow. Therefore, the process of the heat exchanger 20 regulating humidity will not affect the indoor air temperature.

[0066] It is understood that the air conditioner 100 provided in the embodiments of this application may have different structures, and the structure of the air conditioner 100 may also be other types of combinations. The above-described structure of the air conditioner 100 is only an example.

[0067] In some embodiments, such as Figure 3 As shown, Figure 3 This is a partial structural diagram of the heat exchanger 20 provided in an embodiment of this application. The heat exchanger 20 may include multiple fins 23, multiple heat exchange tubes 24, and a moisture-absorbing layer 25. Figure 11 Multiple heat exchange tubes 24 are installed in contact with multiple fins 23. A moisture-absorbing layer 25 is provided at least on the surface of the fins 23.

[0068] The moisture-absorbing layer 25 can absorb water molecules in the airflow passing through it, and can also release water molecules from its own body into the airflow passing through it, so that the heat exchanger 20 coated with the moisture-absorbing layer 25 has the function of moisture exchange.

[0069] In some embodiments, a moisture-absorbing material may also be disposed on the surface of the heat exchange tube 24.

[0070] When the moisture-absorbing material is coated onto the fins 23 of the heat exchanger 20, the fins 23 and the heat exchange tubes 24 are already assembled. Therefore, the heat exchange tubes 24 are also coated with moisture-absorbing material, forming a moisture-absorbing layer 25 on the surface of the heat exchange tubes 24. This moisture-absorbing layer 25 covers a larger area, allowing it to absorb and release more water molecules, thus increasing the moisture absorption efficiency of the heat exchanger 20.

[0071] This application also provides a method for coating a heat exchanger with a moisture-absorbing material, used to coat the surface of the heat exchanger with a moisture-absorbing material to improve the moisture absorption performance of the heat exchanger. Figure 4 As shown, Figure 4 This is one of the schematic diagrams of the method steps for coating a heat exchanger with a moisture-absorbing material according to an embodiment of this application. The method for coating a heat exchanger with a moisture-absorbing material includes steps S100 to S300.

[0072] S100: A method for coating a heat exchanger with a moisture-absorbing material includes immersing the heat exchanger in the moisture-absorbing material solution and removing it after a preset time.

[0073] S200: The heat exchanger is placed in a vacuum environment for material extraction to remove excess moisture-absorbing material from the surface of the heat exchanger.

[0074] S300: Curing and drying the moisture-absorbing material on the surface of the heat exchanger.

[0075] The method for coating a heat exchanger with a moisture-absorbing material provided in this application involves first coating the surface of the heat exchanger fins with a sufficient amount of moisture-absorbing material through an impregnation method. Then, the heat exchanger is removed and vacuum-extracted to remove excess moisture-absorbing material, ensuring that the remaining moisture-absorbing material on the heat exchanger surface is of a suitable thickness. Finally, the heat exchanger is cured and dried, allowing the moisture-absorbing material to firmly adhere to the surface of the heat exchanger.

[0076] Placing the heat exchanger impregnated with moisture-absorbing material in a vacuum environment for material removal prevents impurities in the air from affecting the moisture-absorbing material and altering its properties. Simultaneously, the vacuum environment ensures consistent pressure throughout the heat exchanger, guaranteeing a uniform thickness of the moisture-absorbing material across the entire unit.

[0077] For example, the amount of moisture-absorbing material applied per unit area can be greater than or equal to 0.5 g / 100 cm². 2 Furthermore, the amount of moisture-absorbing material applied per unit area is less than or equal to 1.5 g / 100 cm². 2 .

[0078] Specifically, the coating amount of the moisture-absorbing material per unit area can be 0.5g / 100cm². 2 0.6g / 100cm 2 0.8g / 100cm 2 0.9g / 100cm2 1g / 100cm 2 1.2g / 100cm 2 1.4g / 100cm 2 Or 1.5g / 100cm 2 .

[0079] If the coating amount per unit area is too low, the amount of moisture-absorbing material coated on the fins will be insufficient, reducing the heat exchanger's moisture exchange capacity. If the coating amount per unit area is too high, the thickness of the moisture-absorbing material coated on the fins will be too high, affecting the space between adjacent fins and reducing the amount of airflow between the fins, thereby reducing the heat exchanger's heat exchange and moisture exchange efficiency.

[0080] For example, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the structure of the vacuum coating equipment 40 provided in this application embodiment. A heat exchanger impregnated with moisture-absorbing material can be placed into the vacuum coating equipment 40 for material extraction. The vacuum coating equipment 40 may include a vacuum buffer tank 41, a water ring vacuum unit 42, a coating host 43, and a storage tank (not shown in the figure).

[0081] The vacuum buffer tank 41 provides a vacuum volume, the water ring vacuum unit 42 can evacuate the vacuum buffer tank 41, and the coating host 43 is an operating table that carries the coating tooling and the device to be coated.

[0082] Specifically, when the vacuum coating equipment 40 is working, the water ring vacuum unit 42 pre-extracts a certain negative pressure vacuum into the vacuum buffer tank 41. When it is necessary to remove the vacuum, the control panel is operated to start the vacuuming action. The excess moisture-absorbing material on the heat exchanger is instantly evacuated. Under the action of the airflow, the extracted excess moisture-absorbing material is carried into the storage tank, realizing the recycling and reuse of the moisture-absorbing material.

[0083] In other embodiments, the heat exchanger impregnated with the moisture-absorbing material can also be placed in other equipment, as long as it can provide a vacuum environment and perform material extraction.

[0084] In some embodiments, in the step of placing the heat exchanger in a vacuum environment for material extraction to remove excess moisture-absorbing material from the surface of the heat exchanger, the vacuum level of the vacuum environment may be greater than or equal to -70 kPa, and the vacuum level of the vacuum environment may be less than or equal to -50 kPa.

[0085] Specifically, the vacuum level of the vacuum environment can be -70 kPa, -65 kPa, -60 kPa, -55 kPa, or -50 kPa.

[0086] If the vacuum level is too low, the interactions between molecules will be significantly reduced, thus affecting the effectiveness of practical applications. If the vacuum level is too high, it will not be able to reduce impurities and ensure equal pressure across the heat exchanger.

[0087] Specifically, when the vacuum level is greater than -50 kPa, the force required to draw the vacuum is relatively small, preventing the appropriate amount of moisture-absorbing material coated on the heat exchanger from being extracted, thus affecting the moisture absorption efficiency of the final product. When the vacuum level is less than -70 kPa, the force required to draw the vacuum is relatively large, causing more moisture-absorbing material to be removed, thus affecting the efficiency of the moisture-absorbing layer formation in the heat exchanger.

[0088] In some embodiments, such as Figure 6 As shown, Figure 6 The second schematic diagram of the method steps for coating a heat exchanger with a moisture-absorbing material according to the embodiments of this application further includes step S010 before immersing the heat exchanger in the moisture-absorbing material solution and removing it after a preset time.

[0089] S010: Perform degreasing treatment on the surface of the heat exchanger to remove oil stains from the surface of the heat exchanger.

[0090] During the stamping process of heat exchanger assembly, stamping oil is applied to the surface of the heat exchanger to prevent the components from cracking. The main components of stamping oil are low-boiling-point organic solvents with alkanes as the main component. The presence of these oils can prevent hygroscopic materials from adhering to the heat exchanger or result in uneven adhesion.

[0091] In some embodiments, such as Figure 7 As shown, Figure 7 This is one of the schematic diagrams of a method for degreasing the surface of a heat exchanger to remove oil stains from the surface of the heat exchanger, provided in an embodiment of this application. The method for degreasing the surface of a heat exchanger to remove oil stains from the surface of the heat exchanger includes step S011.

[0092] S011: Heat the heat exchanger at high temperature to evaporate the oil on the surface of the heat exchanger.

[0093] Because the main components of stamping oil are low-boiling-point organic solvents with alkanes as the main component, high-temperature heating will cause these organic solvents to evaporate, thereby achieving the purpose of degreasing.

[0094] In some embodiments, such as Figure 8 As shown, Figure 8 The second schematic diagram of the method steps for degreasing the surface of a heat exchanger to remove oil stains provided in the embodiments of this application includes step S012 after the heat exchanger is heated at a high temperature to evaporate the oil on the surface of the heat exchanger.

[0095] S012: Place the heat exchanger in an aqueous solution of alcohol or surfactant and treat it with ultrasound to further remove residual oil stains.

[0096] To prevent some oil from remaining and not completely evaporating under high temperatures, the heat exchanger, after high-temperature degreasing, can be soaked and rinsed in an alcohol or surfactant solution to further remove oil from its surface. Simultaneously, for more thorough degreasing, the alcohol or surfactant solution used to soak the heat exchanger can be subjected to ultrasonic treatment to accelerate the degreasing process.

[0097] In some embodiments, such as Figure 9 As shown, Figure 9 This is one of the schematic diagrams of a method for curing and drying the moisture-absorbing material on the surface of a heat exchanger, provided in an embodiment of this application. The method for curing and drying the moisture-absorbing material on the surface of a heat exchanger includes step S310.

[0098] S310: Dry the heat exchanger in an environment with a temperature greater than or equal to 20°C and less than or equal to 50°C.

[0099] Specifically, the heat exchanger can be dried at 20℃, 30℃, 33℃, 42℃ and 50℃.

[0100] Curing at low temperatures ensures that the material on the side of the moisture-absorbing layer closest to the heat exchanger also cures, preventing a decrease in the adhesion of the moisture-absorbing layer.

[0101] In some embodiments, such as Figure 10 As shown, Figure 10 This is a second schematic diagram of the method steps for curing and drying the moisture-absorbing material on the surface of a heat exchanger provided in this application embodiment. The curing and drying of the moisture-absorbing material on the surface of the heat exchanger also includes step S320.

[0102] S320: The dried heat exchanger is cured in an environment with a temperature greater than or equal to 100°C and less than or equal to 140°C.

[0103] Specifically, the heat exchanger can be cured at temperatures of 100℃, 110℃, 120℃, 130℃ or 140℃.

[0104] After the heat exchanger is cured at low temperature, it needs to be cured at high temperature. High-temperature curing can further enhance the curing degree of the moisture-absorbing layer, making the moisture-absorbing layer bond more firmly to the surface of the heat exchanger.

[0105] The moisture-absorbing layer 25 provided in this application embodiment can have different structures. The structure of the moisture-absorbing layer 25 provided in this application embodiment will be described in detail below.

[0106] like Figure 11As shown, Figure 11 This is one of the structural schematic diagrams of the moisture-absorbing layer 25 provided in the embodiments of this application. The moisture-absorbing layer 25 may include a moisture-absorbing material 251.

[0107] In some embodiments, the moisture-absorbing material 251 may include a polymeric moisture-absorbing material 2511 and an inorganic moisture-absorbing material 2512. The polymeric moisture-absorbing material 2511 is used to absorb water molecules. The inorganic moisture-absorbing material 2512 is used to enhance the strength of the moisture-absorbing material 251.

[0108] Both the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 are capable of absorbing and releasing water molecules.

[0109] In some embodiments, the polymeric moisture-absorbing material 2511 has hydrophilic groups; furthermore, the polymeric moisture-absorbing material 2511 can be a polymer with a three-dimensional cross-linked network structure.

[0110] The polymeric moisture-absorbing material 2511 has excellent moisture absorption properties and can quickly absorb moisture from the air, thereby improving the moisture absorption efficiency of the heat exchanger 20.

[0111] For example, the polymeric moisture-absorbing material 2511 may include one or more of polyvinyl alcohol, sodium polyacrylate, polyacrylic acid, polyethylene glycol, polyvinylamide, polyamide, polylactic acid, polyether polyol, povidone, and polymeric hydrogel.

[0112] During the water absorption process, the polymeric moisture-absorbing material 2511 undergoes molecular chain expansion, resulting in an increase in overall volume, which can cause cracking of the moisture-absorbing layer 25. Therefore, a material that does not undergo volume change upon water absorption can be added to the moisture-absorbing material 251 to mitigate this phenomenon.

[0113] Due to its porous structure, the inorganic moisture-absorbing material 2512 does not undergo volume change after absorbing water. Therefore, the moisture-absorbing material 251 needs to work together with the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 to ensure the moisture absorption performance and strength of the moisture-absorbing layer 25.

[0114] For example, the inorganic moisture-absorbing material 2512 may include one or more of molecular sieves, activated alumina and metal-organic framework materials.

[0115] In other embodiments, the inorganic moisture-absorbing material 2512 can also be other types of materials, as long as its volume does not change after absorbing moisture. The inorganic moisture-absorbing material 2512 may also include materials such as silica gel, bentonite, activated carbon, and calcium carbonate.

[0116] Inorganic moisture-absorbing material 2512, due to its inherent properties, can improve the overall hardness and wear resistance of the moisture-absorbing coating, thereby enhancing the scratch resistance and impact resistance of the moisture-absorbing coating. Some of the inorganic moisture-absorbing material 2512 can also enhance the adhesion between the moisture-absorbing material 251 and the fins 23, thereby enhancing the adhesion of the moisture-absorbing material 251.

[0117] In some embodiments, the mass ratio of inorganic moisture-absorbing material 2512 to polymeric moisture-absorbing material 2511 is greater than or equal to 1 / 20, and the mass ratio of inorganic moisture-absorbing material 2512 to polymeric moisture-absorbing material 2511 is less than or equal to 1.

[0118] Specifically, the mass ratio of inorganic moisture-absorbing material 2512 to polymeric moisture-absorbing material 2511 can be 1 / 20, 1 / 15, 1 / 10, 1 / 5, 1 / 3, 1 / 2 or 1.

[0119] When the proportion of inorganic moisture-absorbing material 2512 is low, the moisture-absorbing layer 25 formed by coating the surface of the fin 23 with moisture-absorbing material 251 will still undergo significant changes after absorbing water, resulting in cracking of the moisture-absorbing layer 25. Conversely, when the proportion of inorganic moisture-absorbing material 2512 is high, the overall moisture absorption performance of the moisture-absorbing layer 25 will decrease.

[0120] In some embodiments, the mass ratio of molecular sieve to polymeric moisture-absorbing material 2511 is greater than or equal to 1 / 10, and the mass ratio of inorganic moisture-absorbing material 2512 to polymeric moisture-absorbing material 2511 is less than or equal to 4 / 10.

[0121] Alternatively, the mass ratio of molecular sieve material to polymeric moisture-absorbing material 2511 is greater than or equal to 6 / 10, and the mass ratio of inorganic moisture-absorbing material 2512 to polymeric moisture-absorbing material 2511 is less than or equal to 9 / 10.

[0122] Specifically, the mass ratio of molecular sieve to polymer hygroscopic material 2511 can be 1 / 10, 2 / 10, 3 / 10 or 4 / 10.

[0123] When the mass ratio of molecular sieve to polymeric moisture-absorbing material 2511 is 1 / 10, the moisture absorption effect is relatively good.

[0124] Alternatively, the mass ratio of molecular sieve to polymeric moisture-absorbing material 2511 can be 6 / 10, 7 / 10, 8 / 10, and 9 / 10.

[0125] When the mass ratio of molecular sieve to polymeric moisture-absorbing material 2511 is 9 / 10, the moisture absorption effect is relatively good.

[0126] In some embodiments, such as Figure 11As shown, the moisture-absorbing material 251 may also include an adhesive 2513. The adhesive 2513 enables the polymer material and the inorganic moisture-absorbing material 2512 to adhere stably to the surface of the heat exchanger 20.

[0127] For example, adhesive 2513 may include an aqueous resin. The aqueous resin is bonded to the polymeric hygroscopic material 2511.

[0128] Water-based resins refer to polymer resins that can be dispersed or dissolved in water. They have a certain viscosity and can combine with the polymer hygroscopic material 2511, making the polymer dilution material adhere to the surface of the fin 23 and not easily fall off.

[0129] In some embodiments, the adhesive 2513 may further comprise an aqueous emulsion. The aqueous emulsion is bonded to the polymeric hygroscopic material 2511.

[0130] Aqueous emulsions are adhesives that use water as the primary dispersion medium. They exhibit good water resistance and are suitable for use in humid environments. This allows the moisture-absorbing material 251 to have better adaptability and a longer service life.

[0131] In some embodiments, the adhesive 2513 may further comprise an aqueous resin and an aqueous emulsion. The aqueous resin is bonded to the polymeric hygroscopic material 2511. The aqueous emulsion is bonded to the polymeric hygroscopic material 2511.

[0132] Meanwhile, to enable the moisture-absorbing layer 25 to adapt to a wider range of environments, water-based resin and water-based emulsion binders 2513 can be added to the moisture-absorbing material 251. Furthermore, since water-based resins and water-based emulsions use water as the dispersion medium, the use of organic solvents is reduced, thus lowering the emission of volatile organic compounds, meeting environmental protection requirements, and protecting the health of people indoors.

[0133] In some embodiments, the adhesive 2513 may include one or more of the following: aqueous acrylic emulsion, aqueous polyurethane, aqueous epoxy resin, styrene-butadiene latex, or aqueous polycarbonate emulsion.

[0134] In other embodiments, the adhesive 2513 may be made of other materials, as long as it can firmly fix the polymer material and the inorganic moisture-absorbing material 2512 to the surface of the fin 23.

[0135] In some embodiments, the mass ratio of the adhesive 2513 to the polymeric moisture-absorbing material 2511 is greater than or equal to 1 / 5, and the mass ratio of the adhesive 2513 to the polymeric moisture-absorbing material 2511 is less than or equal to 1.

[0136] Specifically, the mass ratio of adhesive 2513 to polymer moisture-absorbing material 2511 can be 1 / 5, 2 / 5, 3 / 5, 4 / 5 or 1.

[0137] If the proportion of adhesive 2513 is too low, the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 will not be able to be stably fixed on the surface of the fin 23. If the proportion of adhesive 2513 is too high, the moisture-absorbing layer 25 will be too dense, and the proportion of polymeric moisture-absorbing material 2511 and inorganic moisture-absorbing material 2512 will be too low, resulting in a decrease in moisture absorption efficiency.

[0138] In some embodiments, such as Figure 11 As shown, the moisture-absorbing material 251 may also include a crosslinking agent 2514. The crosslinking agent 2514 can crosslink with the binder 2513, the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512, and perform physical and chemical crosslinking with the substances in contact with it, so that they are combined with other substances to achieve the effect of not separating.

[0139] In some embodiments, crosslinking agent 2514 may include one or more of isocyanate crosslinking agents, aziridine crosslinking agents, carbodiimide, and epoxy silane compounds.

[0140] In other embodiments, the crosslinking agent 2514 may also include other materials, as long as they are capable of crosslinking with the binder 2513, the polymeric hygroscopic material 2511, and the inorganic hygroscopic material 2512.

[0141] In some embodiments, the mass ratio of adhesive 2513 to crosslinking agent 2514 is greater than or equal to 2, and the mass ratio of adhesive 2513 to crosslinking agent 2514 is less than or equal to 15.

[0142] Specifically, the mass ratio between binder 2513 and crosslinking agent 2514 can be 2, 5, 6, 8, 9, 10, 1 and 15.

[0143] If the proportion of crosslinking agent 2514 is too small, it will not provide a strong adhesive effect and will not be able to stably fix the moisture-absorbing material 251 to the surface of the fin 23. If the proportion of crosslinking agent 2514 is too large, it will result in a small proportion of adhesive 2513, making it unable to effectively perform both adhesive effects.

[0144] As described above, the polymeric moisture-absorbing material 2511 has hydrophilic groups. In some embodiments, the adhesive 2513 has active groups. The active groups react with the hydrophilic groups to form chemical bonds, thereby connecting the adhesive 2513 to the polymeric moisture-absorbing material 2511.

[0145] The hydrophilic groups can chemically react and connect with the active groups, making the polymeric moisture-absorbing material 2511 and the adhesive 2513 bonded together and not easily separated. The adhesive 2513 can adhere to the fins, and at the same time, it also adheres the polymeric moisture-absorbing material 2511 to the fins. This makes the moisture-absorbing layer 25 less likely to fall off the fins.

[0146] In some embodiments, the hydrophilic group includes one or more of carboxyl and hydroxyl groups. The active group includes one or more of isocyanate and epoxy groups.

[0147] Among them, such as Figure 12 , Figure 13 and Figure 14 As shown, Figure 12 This is a schematic diagram of the chemical equation for the reaction between the polymeric moisture-absorbing material provided in the embodiments of this application and one of the adhesives. Figure 13 This is a schematic diagram of the chemical equation for the reaction between the polymeric hygroscopic material and the crosslinking agent provided in the embodiments of this application. Figure 14 This is a schematic diagram of the chemical equation for the reaction between the polymeric moisture-absorbing material provided in the embodiments of this application and another adhesive.

[0148] The isocyanate groups and epoxy groups in the adhesive 2513 can react with carboxyl or hydroxyl groups to form chemical bonds, thereby connecting the adhesive 2513 and the polymer moisture-absorbing material 2511 molecules together.

[0149] In other embodiments, the active groups on the adhesive 2513 may also include other types of groups, as long as the groups can be chemically bonded to hydroxyl or carboxyl groups so that the adhesive 2513 and the polymeric moisture-absorbing material 2511 can be connected together.

[0150] For example, when the polymer moisture-absorbing material 2511 has a cross-linked network structure, the polymer inside the polymer moisture-absorbing material 2511 has a rich cross-linked network structure. When these cross-linked network structures come into contact with water, they can undergo capillary action, which promotes the rapid diffusion of water inside the polymer moisture-absorbing material 2511.

[0151] Furthermore, the polymer main chain or grafted side chain of the polymer moisture-absorbing material 2511 contains hydrophilic groups such as hydroxyl, carboxyl, and amide groups. These hydrophilic groups can react with polar water molecules to form hydrogen bonds, allowing water molecules to continuously penetrate into the cross-linked network structure of the polymer moisture-absorbing material 2511.

[0152] When the 2511 polymer moisture-absorbing material comes into contact with water, it generates a large number of ions, creating a certain ion concentration difference between the inside and outside of the polymer, and thus a potential difference in the solution. This potential difference promotes the accumulation of water from the outside to the inside of the polymer, thereby increasing the moisture absorption performance of the 2511 polymer moisture-absorbing material.

[0153] Structurally, the 2511 polymer moisture-absorbing material has a slightly modified spatial network structure, which is composed of chemical cross-linking and the entanglement and cross-linking between resin molecular chains. Before the polymer absorbs water, the long chains of adjacent polymers will come together and intertwine to form a network structure, achieving an overall tightness.

[0154] Specifically, before absorbing water, the hygroscopic polymer is a solid network and has not yet ionized into ion pairs. When the hygroscopic polymer encounters water, the hydration of the hydrophilic groups with water molecules causes the polymer network to unfold, and the ionized particles create osmotic pressure inside and outside the hygroscopic polymer. Water molecules move into the hygroscopic polymer under the influence of osmotic pressure.

[0155] Therefore, when the adsorbed solution contains salts, the osmotic pressure decreases, and the water absorption capacity decreases accordingly. It is evident that the hydrophilic groups in the hygroscopic polymer network structure are indispensable; they function to enable the hygroscopic polymer network structure to unfold and generate osmotic pressure.

[0156] Meanwhile, the pore size of the network structure of hygroscopic polymers is also related to water absorption efficiency. The larger the pore size, the higher the water absorption efficiency, and vice versa.

[0157] In some embodiments, such as Figure 15 As shown, Figure 15 This is a second schematic diagram of the structure of the moisture-absorbing layer 25 provided in this application embodiment. The moisture-absorbing layer 25 may include an adhesive layer 252 and a moisture-absorbing material layer 253. The adhesive layer 252 is disposed on the surface of the heat exchanger 20. A layer is stacked on the side of the adhesive layer 252 away from the heat exchanger 20 and is connected to the heat exchanger 20 through the adhesive layer 252.

[0158] The adhesive layer 252 may include an adhesive 2513 and a crosslinking agent 2514. The moisture-absorbing material layer 253 may include a polymeric moisture-absorbing material 2511 and an inorganic moisture-absorbing material 2512.

[0159] In some embodiments, the moisture-absorbing material layer 253 may further include an adhesive 2513 and a crosslinking agent 2514.

[0160] If the moisture-absorbing layer 25 only contains the moisture-absorbing material layer 253, the moisture-absorbing material 251 will affect the adhesive strength between the moisture-absorbing layer 25 and the fin 23, making the moisture-absorbing layer 25 easy to detach from the fin 23. Therefore, it is necessary to add an adhesive layer 252 without moisture-absorbing material 251 between the moisture-absorbing material layer 253 and the fin 23 to strengthen the adhesive strength between the moisture-absorbing layer 25 and the fin 23.

[0161] The adhesive 2513 in the adhesive layer 252 is used to bond the moisture-absorbing material layer 253 to the surface of the heat exchanger 20. The adhesive 2513 in the adhesive layer 252 can crosslink with the adhesive 2513 in the adhesive layer 252 and the moisture-absorbing material layer 253 to improve the bonding strength between the adhesive layer 252 and the moisture-absorbing material layer 253.

[0162] This ensures that the moisture-absorbing material layer 253 and the adhesive layer 252 can be tightly bonded together, thereby ensuring that the moisture-absorbing material layer 253 can be firmly bonded to the surface of the fin 23 through the adhesive layer 252.

[0163] In the adhesive layer 252, the adhesive 2513 and the crosslinking agent 2514 can crosslink to form a dense network structure, giving it excellent adhesion to the surface of the heat exchanger 20. At the same time, the adhesive layer 252 provides a certain number of anchor points for the moisture-absorbing material layer 253, which are functional groups that can react and bind with the substances in the moisture-absorbing material layer 253.

[0164] Through these anchor points, the moisture-absorbing material layer 253 can establish a precise and stable connection with the adhesive layer 252, preventing the moisture-absorbing material layer 253 from easily detaching. This forms a moisture-absorbing layer 25 that can be stably connected to the heat exchanger 20.

[0165] The adhesive layer 252 and the moisture-absorbing material layer 253 are connected by anchor points, forming cross-linked molecular bonds. Meanwhile, the locations on the heat exchanger 20 where the moisture-absorbing material 251 needs to be coated will have some active functional groups due to activation. Therefore, an adhesive 2513 capable of binding with these active functional groups can be selected, allowing the adhesive layer 252 to chemically bond with the surface of the heat exchanger 20, also forming cross-linked molecular bonds.

[0166] Meanwhile, the molecules of adhesive 2513 and the molecules on the surface of heat exchanger 20 have van der Waals forces and hydrogen bonds. Although these forces are smaller than the forces connecting functional groups, they still allow the adhesive layer 252 to adhere to the surface of heat exchanger 20, thereby enhancing the stability of the adhesion of the adhesive layer 252 on the surface of heat exchanger 20.

[0167] It is understandable that when the distance between the adhesive 2513 molecule and the molecule to be bonded is less than or equal to 10 angstroms, the two molecules can generate mutual attraction, which further shortens the distance between the molecules under the action of the attraction until the two molecules are in a state of maximum stability.

[0168] In related technologies, the absence of an adhesive layer 252 limits the number of anchor points that can connect the moisture-absorbing layer 25 to the surface of the heat exchanger 20, thus limiting the bonding force between the moisture-absorbing layer 25 and the surface of the heat exchanger 20.

[0169] Meanwhile, the presence of the moisture-absorbing material 251 increases the distance between the adhesive 2513 molecules and the surface molecules of the heat exchanger 20, thereby reducing the van der Waals forces and hydrogen bonds between the adhesive 2513 molecules and the surface molecules of the heat exchanger 20, resulting in insufficient bonding between the moisture-absorbing layer 25 and the heat exchange layer. Therefore, the moisture-absorbing layer 25 in the prior art is prone to detaching from the surface of the heat exchanger 20.

[0170] In some embodiments, in the moisture-absorbing material layer 253, the ratio of the sum of the mass of the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 to the mass of the adhesive 2513 can be greater than or equal to 1, and the ratio of the sum of the mass of the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 to the mass of the adhesive 2513 is less than or equal to 3.

[0171] Specifically, the ratio of the sum of the masses of the polymeric moisture-absorbing material 2511 and the inorganic moisture-absorbing material 2512 to the mass of the binder 2513 can be 1, 1.5, 1.7, 2, 2.3, 2.6, 2.8 or 3.

[0172] When the proportion of adhesive 2513 is low, the moisture-absorbing layer 25 is easily detached under external influences. When the proportion of adhesive 2513 is high, the moisture-absorbing layer 25 becomes too dense, and the proportion of polymeric moisture-absorbing material 2511 and inorganic moisture-absorbing material 2512 is too small, resulting in reduced moisture absorption efficiency.

[0173] When applying the adhesive layer 252 and the moisture-absorbing material layer 253 using the method of applying moisture-absorbing material 251 to the heat exchanger 20, the adhesive layer 252 is first applied to the heat exchanger 20. After the adhesive layer 252 is applied and dried, the moisture-absorbing material layer 253 is then applied to the adhesive layer 252.

[0174] The adhesive coating used to coat the adhesive layer 252 includes an adhesive 2513, a crosslinking agent 2514, and a solvent. The above components are added to a container while stirring until all components are dissolved in the solvent and the entire system reaches a stable state.

[0175] When applying the adhesive layer 252, the heat exchanger 20 is immersed in the adhesive coating for a period of 1 minute or more and 3 minutes or less. Then, the heat exchanger 20 is removed at an angle to the ground. When the adhesive coating on the heat exchanger 20 no longer flows, the heat exchanger 20 is placed on the coating fixture in a vacuum coating machine for vacuum extraction.

[0176] Specifically, the impregnation time can be 1 min, 1.2 min, 1.5 min, 2.8 min, or 3 min. If the impregnation time is too short, there will be less adhesive material adhering to the heat exchanger 20, making the moisture-absorbing layer 25 easy to detach from the heat exchanger 20. If the impregnation time is too long, there will be too much material adhering to the heat exchanger 20, making it difficult to control the thickness of the adhesive layer 252 within a suitable range.

[0177] After removing excess adhesive coating from heat exchanger 20, heat exchanger 20 is dried at low temperature to allow adhesive layer 252 to dry completely. Then, heat exchanger 20 is cured at high temperature to further strengthen the connection between adhesive layer 252 and heat exchanger 20.

[0178] Simultaneously, before immersing the heat exchanger 20 in the adhesive coating, the heat exchanger 20 needs to be weighed, and its weight before applying the adhesive coating should be recorded. After the adhesive material has dried and cured, the heat exchanger 20 should be weighed again to determine if the weight of the adhesive layer 252 is acceptable. If the weight of the adhesive layer 252 does not meet the standard, it can be coated multiple times until the weight of the adhesive layer 252 meets the standard.

[0179] The high-temperature curing temperature can be adjusted according to the properties of the selected materials, such as polymer moisture-absorbing material 2511, inorganic moisture-absorbing material 2512, adhesive 2513 and crosslinking agent 2514, to ensure that the curing process can stably adhere the adhesive layer 252 to the surface of the heat exchanger 20 without damaging the chemical structure of the adhesive 2513.

[0180] After the adhesive layer 252 is applied, the moisture-absorbing material layer 253 can be applied next. First, the polymer moisture-absorbing material 2511, inorganic moisture-absorbing material 2512, adhesive 2513, binder and solvent can be added to a container while stirring until all materials are dissolved in the solvent, so that the entire moisture-absorbing coating reaches a stable state.

[0181] Then, the heat exchanger 20 with the adhesive layer 252 formed is immersed in the moisture-absorbing coating for a time of 1 minute or more and less than or equal to 3 minutes. After this time, the heat exchanger 20 is removed at a certain angle to the ground. When the moisture-absorbing coating on the heat exchanger 20 no longer flows, the heat exchanger 20 is placed on the coating fixture in a vacuum coating machine for vacuum extraction.

[0182] Specifically, the impregnation time can be 1 min, 1.2 min, 1.5 min, 2.8 min, or 3 min. If the impregnation time is too short, less moisture-absorbing material 251 will adhere to the heat exchanger 20, reducing the moisture absorption effect of the heat exchanger 20. If the impregnation time is too long, the thickness of the moisture-absorbing material layer 253 will be too thick, and some of the moisture-absorbing material 251 will not adhere tightly to the heat exchanger 20, making it easy to fall off.

[0183] After removing excess moisture-absorbing coating from heat exchanger 20, heat exchanger 20 is dried at low temperature to ensure the moisture-absorbing material layer 253 is completely dry. Then, heat exchanger 20 is cured at high temperature to further strengthen the connection between the moisture-absorbing layer 25 and the adhesive layer 252.

[0184] In particular, the viscosity of the moisture-absorbing coating needs to be controlled when applying the moisture-absorbing material layer 253.

[0185] In some embodiments, the viscosity of the hygroscopic material 251 is greater than or equal to 200 mPa·s, and the viscosity of the wet material is less than or equal to 300 mPa·s.

[0186] Specifically, the viscosity of the hygroscopic material 251 can be 200 mPa·s, 220 mPa·s, 222 mPa·s, 260 mPa·s, 280 mPa·s, 290 mPa·s or 300 mPa·s.

[0187] If the viscosity of the moisture-absorbing material 251 is too high during the process of coating the heat exchanger 20, the flow rate of the moisture-absorbing material 251 on the surface of the heat exchanger 20 will be slow, and the excess moisture-absorbing material 251 will not be easily extracted.

[0188] If the viscosity of the moisture-absorbing material 251 is too low, the amount of moisture-absorbing material 251 applied to the heat exchanger 20 each time will be too low. In order to make the thickness of the moisture-absorbing layer 25 on the heat exchanger 20 meet the standard, it is necessary to increase the number of coatings, which will increase the manufacturing time and cost.

[0189] Furthermore, the vacuum level needs to be controlled during both the application of adhesive coatings and moisture-absorbing coatings. The vacuum level can be the same for both types of coatings, with the vacuum level of the vacuum environment being greater than or equal to -70 kPa and less than or equal to -50 kPa.

[0190] Specifically, the vacuum level of the vacuum environment can be -70 kPa, -65 kPa, -60 kPa, -55 kPa, or -50 kPa.

[0191] Weighing can be performed before and after applying the moisture-absorbing coating to the heat exchanger 20, or the thickness of the moisture-absorbing material layer 253 can be measured after the moisture-absorbing coating has been dried and cured. Experiments show that when the thickness of the moisture-absorbing material layer 253 is greater than or equal to 200 μm and less than or equal to 300 μm, the moisture-absorbing layer 25 can achieve a good humidity control effect. To achieve this effect, in actual operation, the process of applying the moisture-absorbing coating can be repeated more than or equal to 3 times and less than or equal to 5 times.

[0192] In some embodiments, the moisture-absorbing material 251 may further include a curing agent. The curing agent is used to accelerate the curing speed of the moisture-absorbing material 251.

[0193] If no curing agent is added to the moisture-absorbing material 251, the curing time of the moisture-absorbing material 251 on the surface of the fin 23 will be relatively long. During the long curing process, the moisture-absorbing material 251 may be affected by external factors, resulting in deformation or other issues of the moisture-absorbing layer 25.

[0194] After adding a curing agent to the moisture-absorbing material 251, the moisture-absorbing material 251 can be quickly cured after being coated onto the surface of the fin 23, making the moisture-absorbing layer 25 strong and stable. At the same time, the curing agent can also react with the adhesive 2513 to form a stronger and more stable polymer network, further enhancing the strength of the moisture-absorbing layer 25.

[0195] In some embodiments, the curing agent may include an epoxy curing agent. The mass ratio of the epoxy curing agent to the adhesive 2513 is greater than or equal to 2 / 5, and the mass ratio of the epoxy curing agent to the adhesive 2513 is less than or equal to 3 / 5.

[0196] For example, epoxy curing agents may include polyamine curing agents, polyamide curing agents, amine adduct curing agents, phenolic amine curing agents, and water-based curing agents. Among them, polyamide curing agents can be polyamide resins. Polyamide curing agents have good toughness and chemical resistance, and the cured coating has good mechanical properties.

[0197] Specifically, the ratio of the mass of epoxy curing agent to the mass of adhesive 2513 can be 2 / 5, 9 / 20, 1 / 2, 11 / 20, or 3 / 5.

[0198] If the curing agent content is low, the curing speed of the moisture-absorbing material 251 will still be slow, and it will be affected by external factors during curing, affecting the strength of the moisture-absorbing layer 25. If the curing agent content is high, the content of the adhesive 2513 will decrease, making it difficult for the polymer moisture-absorbing material 2511 to adhere to the fin 23, and causing the moisture-absorbing material 251 to easily fall off the surface of the fin 23.

[0199] To verify the performance of the heat exchanger 20 provided in this application embodiment, the performance of the coated heat exchanger 20 can be evaluated.

[0200] In some embodiments, the heat exchanger 20 can be tested for water resistance. Specific testing methods can refer to standard GB / T 1733-93, which involves immersing the sample in water for 48 hours and then observing the surface condition of the sample.

[0201] Specifically, such as Figure 16 As shown, Figure 16 The diagram below illustrates the structure of the device for testing water resistance provided in this embodiment. The method for testing the water resistance of the heat exchanger 20 can be to add distilled water or deionized water to the glass water bath 30. Unless otherwise specified, the temperature of the water 31 can be adjusted to 23±2℃ and maintained at this temperature throughout the testing process.

[0202] Then coat the three pieces with the moisture-absorbing layer 25 ( Figure 11 The heat exchangers 20 are placed in the glass water tank 30, such that 2 / 3 of the length of each heat exchanger 20 is immersed in water 31.

[0203] After the soaking time specified in the product standard is completed, remove the three heat exchangers 20 from the water tank 30 and use filter paper to absorb the excess water on the heat exchangers 20 for 31 minutes. Then, immediately adjust the condition according to the time specified in the product standard and visually inspect the three heat exchangers 20, and record any phenomena such as loss of luster, discoloration, blistering, wrinkling, peeling, and rust, as well as the recovery time.

[0204] Ultimately, if the test structure of at least two of the three heat exchangers 20 meets the product standard requirements, the water resistance of the heat exchanger 20 is considered qualified.

[0205] In some embodiments, the adhesion of the moisture-absorbing layer 25 on the heat exchanger 20 can also be evaluated. Specific evaluation methods can be found in standard GB / T 9286-2021.

[0206] Specifically, such as Figure 17 As shown, Figure 17 The reference diagram for evaluating the adhesion of the moisture-absorbing layer provided in this application embodiment shows that six parallel cuts can be made on the heat exchanger 20 coated with the moisture-absorbing coating, and another six parallel cuts can be made perpendicular to the first cut. Then, all loose coating fragments are removed. Finally, the cut area is visually inspected and compared with a 6-level grading standard to determine the adhesion level of the moisture-absorbing layer 25 on the heat exchanger 20.

[0207] Among them, such as Figure 17 As shown in a, if the cut edge is completely smooth and there is no peeling within the grid, the adhesion level of the moisture-absorbing layer 25 on the heat exchanger 20 is level 0.

[0208] like Figure 17 As shown in b, if a small amount of coating peels off at the intersection of the cuts, but the affected cross-cut area is no more than 5%, then the adhesion level of the moisture-absorbing layer 25 on the heat exchanger 20 is level 1.

[0209] like Figure 17 As shown in c, if the coating peels off at the intersection of the cuts and / or along the edge of the cuts, and the affected cross-cut area is greater than 5% and less than or equal to 15%, then the adhesion grade of the moisture-absorbing layer 25 on the heat exchanger 20 is grade 2.

[0210] like Figure 17 As shown in d, if the coating peels off in large fragments along the cut edge, and / or peels off in large fragments at different locations, with the affected cross-cut area being greater than 15% and less than or equal to 35%, then the adhesion grade of the moisture-absorbing layer 25 on the heat exchanger 20 is grade 3.

[0211] like Figure 17 As shown in e, if large fragments of the coating peel off along the cut edge, and / or some fragments peel off partially or completely, and the affected cross-cut area is greater than 35% and less than or equal to 65%, then the adhesion rating of the moisture-absorbing layer 25 on the heat exchanger 20 is level 4.

[0212] If the degree of detachment exceeds level 4, the adhesion level of the moisture-absorbing layer 25 on the heat exchanger 20 is level 5.

[0213] Understandably, when the adhesion rating is 0, the moisture-absorbing layer 25 has the best adhesion to the heat exchanger 20, and when the adhesion rating is 5, the moisture-absorbing layer 25 has the worst adhesion to the heat exchanger 20.

[0214] The percentages specified above are based on the visual impression given by the image, and the same percentage of affected cross-cutting area may not necessarily be reproduced with the digital image.

[0215] In some embodiments, the water permeability of the moisture-absorbing layer 25 on the heat exchanger 20 can also be evaluated. A 10 μl drop of water can be placed on the surface of the heat exchanger 20 coated with the moisture-absorbing layer 25, and the time required for the water droplet to completely penetrate is recorded.

[0216] Four control groups were set up. The first group involved coating an aluminum plate with a moisture-absorbing layer 25, which consisted of an adhesive layer 252 and a moisture-absorbing material layer 253. The adhesive layer 252 consisted of an adhesive 2513 and a crosslinking agent 2514. The adhesive was an aqueous acrylic emulsion, used at a dry weight of 1 unit. The crosslinking agent 2514 was an isocyanate, used at a dry weight of 0.2 units.

[0217] The moisture-absorbing material layer 253 includes an adhesive 2513, a crosslinking agent 2514, and a moisture-absorbing material 251. The adhesive 2513 is water-based polyurethane, used in an amount of 1 unit dry weight. The crosslinking agent 2514 is carbodiimide, used in an amount of 0.1 unit dry weight. The moisture-absorbing material 251 is inorganic silica gel, used in an amount of 0.5 units.

[0218] The second group specifically involves coating an aluminum plate with a moisture-absorbing layer 25, which comprises only a moisture-absorbing material layer 253. The moisture-absorbing material layer 253 includes an adhesive 2513, a crosslinking agent 2514, and a moisture-absorbing material 251. The adhesive 2513 is water-based polyurethane, used in an amount of 1 unit dry weight. The crosslinking agent 2514 is carbodiimide, used in an amount of 0.1 unit dry weight. The moisture-absorbing material 251 is inorganic silica gel, used in an amount of 0.5 units.

[0219] The third group specifically involves coating an aluminum plate with a moisture-absorbing layer 25, which consists of an adhesive layer 252 and a moisture-absorbing material layer 253. The adhesive layer 252 includes an adhesive 2513. The adhesive 2513 includes an aqueous acrylic emulsion, used in an amount of 1 unit dry weight.

[0220] The moisture-absorbing material layer 253 includes an adhesive 2513, a crosslinking agent 2514, and a moisture-absorbing material 251. The adhesive 2513 is water-based polyurethane, used in an amount of 1 unit dry weight. The crosslinking agent 2514 is carbodiimide, used in an amount of 0.1 unit dry weight. The moisture-absorbing material 251 is inorganic silica gel, used in an amount of 0.5 units.

[0221] The fourth group specifically involves coating a moisture-absorbing layer 25 onto an aluminum plate. This moisture-absorbing layer 25 comprises an adhesive layer 252 and a moisture-absorbing material layer 253. The adhesive layer 252 includes an adhesive 2513 and a crosslinking agent 2514. The adhesive is an aqueous acrylic emulsion, used in an amount of 1 unit dry weight. The crosslinking agent 2514 is isocyanate, used in an amount of 0.2 units dry weight. The moisture-absorbing material layer 253 includes an adhesive 2513 and a moisture-absorbing material 251. The adhesive 2513 is an aqueous polyurethane, used in an amount of 1 unit dry weight, and the moisture-absorbing material 251 is inorganic silicone, used in an amount of 0.5 units.

[0222] The test results of water resistance, adhesion and seepage time for the four control groups are shown in Table 1 below.

[0223] Table 1

[0224] Serial Number Water resistance Adhesion Infiltration time Group 1 qualified Level 0 3min Group 2 Bubbling and peeling Level 1 3min Group 3 bulge Level 1 1min Group 4 Shedding Level 2 1min

[0225] Three control groups can also be set up. The fifth group's moisture-absorbing layer 25 includes a moisture-absorbing polymer containing hydroxyl groups, waterborne polyurethane, isocyanate, molecular sieve, and water. The amount of moisture-absorbing polymer is 1 unit dry weight, the amount of waterborne polyurethane is 0.5 units dry weight, the amount of isocyanate is 0.05 units dry weight, the amount of molecular sieve is 0.1 units dry weight, and the amount of water is 2 units dry weight.

[0226] The sixth group's moisture-absorbing layer 25 includes a hygroscopic polymer containing hydroxyl groups, a waterborne epoxy resin, an epoxy curing agent, a molecular sieve, and water. The amount of the hygroscopic polymer is 1 unit dry weight, the amount of the waterborne epoxy resin is 0.5 units dry weight, the amount of the epoxy curing agent is 0.25 units dry weight, the amount of the molecular sieve is 0.1 units dry weight, and the amount of water is 2 units dry weight.

[0227] The seventh moisture-absorbing layer 25 includes a hygroscopic polymer containing hydroxyl groups, polyvinyl alcohol, molecular sieve, and ethanol. The amount of hygroscopic polymer is 1 unit dry weight, polyvinyl alcohol is 0.5 units dry weight, molecular sieve is 0.1 units dry weight, and ethanol is 2 units dry weight.

[0228] Finally, the test results of water resistance, adhesion and seepage time of the three control groups are shown in Table 2 below.

[0229] Table 2

[0230] Serial Number Water resistance Adhesion Permeability Group 5 qualified Level 0 3min Group 6 qualified Level 0 3min Group 7 peeling Level 1 More than 5 minutes

[0231] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A heat exchanger, characterized by, The heat exchanger comprises: a plurality of fins; a plurality of heat exchange tubes, the plurality of heat exchange tubes being installed in contact with the plurality of fins; and a moisture absorbing material provided at least on a surface of the fins, wherein the moisture absorbing material comprises: a high molecular moisture absorbing material; an inorganic moisture absorbing material mixed with the high molecular moisture absorbing material; and a binder mixed with the high molecular moisture absorbing material and the inorganic moisture absorbing material. The inorganic moisture absorbing material comprises:

2. The heat exchanger of claim 1, wherein a molecular sieve having a porous structure to absorb moisture; and / or an active alumina having a porous structure to absorb moisture; and / or a metal organic framework material having a porous structure to absorb moisture. The binder comprises:

3. The heat exchanger of claim 1, wherein an aqueous resin combined with the high molecular moisture absorbing material; and / or an aqueous emulsion combined with the high molecular moisture absorbing material. The binder comprises one or more of an aqueous acrylic emulsion, an aqueous polyurethane, an aqueous epoxy resin, or a styrene butadiene latex; and / or 4. The heat exchanger of claim 3, wherein The high molecular moisture absorbing material comprises one or more of polyvinyl alcohol, sodium polyacrylate, polyacrylic acid, polyethylene glycol, polyvinylamide, polyamide, polylactic acid, polyether polyol, povidone, and polymer hydrogel. The mass ratio of the inorganic moisture absorbing material to the high molecular moisture absorbing material is greater than or equal to 1 / 20, and the mass ratio of the inorganic moisture absorbing material to the high molecular moisture absorbing material is less than or equal to 1.

5. The heat exchanger according to any one of claims 1 to 4, characterized in that The inorganic moisture absorbing material comprises a molecular sieve; the mass ratio of the molecular sieve to the high molecular moisture absorbing material is greater than or equal to 1 / 10, and the mass ratio of the inorganic moisture absorbing material to the high molecular moisture absorbing material is less than or equal to 4 / 10; or 6. The heat exchanger of claim 5, wherein The mass ratio of the molecular sieve material to the high molecular moisture absorbing material is greater than or equal to 6 / 10, and the mass ratio of the inorganic moisture absorbing material to the high molecular moisture absorbing material is less than or equal to 9 / 10. The mass ratio of the binder to the high molecular moisture absorbing material is greater than or equal to 1 / 5, and the mass ratio of the binder to the high molecular moisture absorbing material is less than or equal to 1.

7. The heat exchanger according to any one of claims 1 to 4, characterized in that The moisture absorbing material is also provided on a surface of the heat exchange tube; and / or 8. The heat exchanger according to any one of claims 1 to 4, characterized in that The viscosity of the moisture absorbing material is greater than or equal to 200 mpa·s, and the viscosity of the moisture absorbing material is less than or equal to 300 mpa·s. The unit area application amount of the moisture absorbing material is greater than or equal to 0.5 g / 100 cm 2 , and the unit area application amount of the moisture absorbing material is less than or equal to 1.5 g / 100 cm 2 .

9. The heat exchanger according to any one of claims 1 to 4, characterized in that The heat exchanger comprises:

10. An air conditioner characterized by comprising: a housing, an accommodation cavity being formed inside the housing; the housing is further provided with an air inlet and an air outlet communicating with the accommodation cavity; and The heat exchanger according to any one of claims 1 to 9 is arranged in the accommodation cavity. ​

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