Coater thermal management system and control method

Abstract

The application discloses a coating machine heat management system and control method, heat exchange finned tube is arranged between the tank and the first condenser for direct heat exchange, the waste hot water main pipe is provided with two three-way valves, and the waste hot water branch pipe is connected to the return water pipe and the water supply pipe near one end of the tank. The coating machine heat management system and control method provided by the application, the latent heat of the airflow in the exhaust pipe is transferred to the first condenser in the tank after being absorbed by the first evaporator, the heat storage water in the tank is heated, and the heat in the heat storage water in the tank is transferred to the second condenser and the third condenser through the second heat pump part and the third heat pump part. The heat obtained by the first heat pump part can be stored and managed through the circulating hot water system, thereby providing a basis for stable work of the whole system. Through the cooperation of the circulating hot water system and the heat management part, multiple working modes can be adjusted, the latent heat can be recycled and utilized, and the latent heat can be supplemented and stored.

Description

Technical Field

[0001] This invention relates to the field of thermal management of coating machines, and particularly to a thermal management system and control method for coating machines. Background Technology

[0002] In existing technologies, coating machines, as a type of industrial coating equipment, are mainly used to achieve high-precision and uniform coating coverage on the surfaces of various substrates. Common coating materials include adhesives, functional inks, protective coatings, and special chemical agents. This equipment plays a crucial role in many industrial fields such as printing and publishing, flexible packaging manufacturing, electronic component production, and new building material processing. Its basic structure typically includes an unwinding unit, a coating head (which can employ different coating processes such as doctor blade coating, roller coating, spray coating, or slot extrusion), a drying or curing system (such as infrared heating, hot air circulation, ultraviolet curing, or electron beam curing devices), and a high-precision winding section. During operation, the substrate (such as plastic film, paper, aluminum foil or composite material) is smoothly output by the unwinding mechanism and enters the coating area after tension control; the coating mechanism applies specific liquid or paste material evenly to the surface of the substrate according to the pre-set thickness and width; then, the coating material passes through the drying oven or curing area and forms a stable coating under controlled temperature, wind speed or light radiation conditions; finally, after cooling and quality inspection, it is wound up by the rewinding device into a finished product.

[0003] During the operation of a coating machine, the drying stage often generates a large amount of high-temperature exhaust gas. If this airflow is discharged directly without treatment, it will cause significant heat loss. A common waste heat recovery method is to use a gas-to-gas heat exchanger, utilizing the heat in the exhaust gas to preheat the fresh air, thereby reducing the energy consumption required to heat the fresh air. However, traditional heat exchange methods have significant limitations: their heat recovery efficiency is limited by the heat exchange area, airflow distribution, and the thermal conductivity of the materials, and it is usually difficult to achieve a high level; at the same time, when there is a large temperature difference between the exhaust air and the fresh air, the temperature of the preheated fresh air may still be low, which cannot fully meet the needs of subsequent heating processes, thus limiting the overall energy efficiency improvement. Waste hot water is often generated during factory production, but it is difficult to establish thermal management between it and the coating head. Summary of the Invention

[0004] The main objective of this invention is to provide a thermal management system and control method for a coating machine, which aims to solve the problems that traditional heat exchange methods have significant limitations, making it difficult to achieve high efficiency and unable to adjust the working mode.

[0005] To achieve the above objectives, the present invention provides a thermal management system for a coating machine, configured corresponding to the coating head, including: The exhaust pipe leads out of the coating head; A first heat exchanger is disposed on the exhaust pipe; The air intake pipe passes through the first heat exchanger and forms a heat exchange with the exhaust pipe, and is connected to the coating head; The first heat pump unit includes a tank and a first evaporator, a first condenser and a first compressor forming a cycle. The first condenser is disposed in the tank, and the first evaporator is disposed on the exhaust pipe and located downstream of the first heat exchanger. The second heat pump section includes a second condenser, a second compressor, and a second heat exchanger that form a cycle, with the second condenser located downstream of the first heat exchanger on the intake pipe. The third heat pump section includes a third condenser, a third compressor, and a third heat exchanger that form a cycle, wherein the third condenser is located downstream of the second condenser on the intake pipe; A circulating hot water system includes a return pipe, a water tank, and a supply pipe equipped with a first water pump. The supply pipe extends from the tank, connects the second heat exchanger and the third heat exchanger in parallel, and then returns to the water tank. The return pipe connects the water tank and the tank. The thermal management unit includes a waste hot water main pipe pair, a waste hot water bypass pipe pair, and a heat exchange finned tube. The waste hot water main pipe pair is circulatedly connected to the heat exchange finned tube and an external waste hot water tank and is equipped with a second water pump. The heat exchange finned tube is located inside the tank and directly exchanges heat with the first condenser. The waste hot water main pipe pair is equipped with two three-way valves to lead out the waste hot water bypass pipe pair and connect to the return water pipe and the supply water pipe near one end of the tank, respectively.

[0006] Furthermore, a first temperature sensor is installed downstream of the third condenser inside the air intake pipe, and a second temperature sensor is installed at one end of the return water pipe connected to the tank.

[0007] Furthermore, the water supply pipe branches into a first water supply pipe and a second water supply pipe, which are then connected to the second heat exchanger and the third heat exchanger, respectively. A first solenoid valve and a second solenoid valve are respectively installed on the first water supply pipe and the second water supply pipe.

[0008] Furthermore, the water supply pipe is connected to the first water supply pipe and the second water supply pipe via a diverter-type three-way valve.

[0009] Furthermore, the heat exchange finned tube and the first condenser are an integral structure.

[0010] Furthermore, the refrigerant used in the second heat pump section is R142b, and the refrigerant used in the third heat pump section is R1233zd.

[0011] Furthermore, the end of the exhaust pipe away from the coating head is connected to the end of the air inlet pipe away from the coating head.

[0012] The present invention also provides a control method applied to the above-mentioned thermal management system of the coating machine, comprising: S1. Based on the data from the first temperature sensor, control the operating intensity of the second compressor and the third compressor; S2. Real-time acquisition of data from the second temperature sensor to obtain the residual temperature of the stored hot water; S3. If the residual temperature of the stored hot water is between B and C degrees, the thermal management system of the coating machine is switched to the balanced working mode. In the balanced working mode, the three-way valve connects the waste hot water main pipe to the heat exchange finned tube, the second water pump stops working, and the first water pump starts working. S4. If the residual temperature of the stored hot water is between A and B degrees, the thermal management system of the coating machine is switched to the supplementary heating mode. In the supplementary heating mode, the three-way valve connects the waste hot water main pipe to the circulating hot water system, and the second water pump is activated. S5. If the residual temperature of the stored hot water is between C and D degrees, the thermal management system of the coating machine is switched to the heat recovery mode. In the heat recovery mode, the three-way valve connects the waste hot water main pipe to the heat exchange finned tube, the second water pump stops working, and the first water pump starts working. Among them, A <B<C<D。

[0013] Furthermore, in step S4, the operating intensity of the first and second water pumps is adjusted according to the residual temperature of the stored hot water.

[0014] Furthermore, the water supply pipe branches into a first water supply pipe and a second water supply pipe, which are then connected to the second heat exchanger and the third heat exchanger, respectively. A first solenoid valve and a second solenoid valve are respectively installed on the first water supply pipe and the second water supply pipe. A third temperature sensor is installed on the air inlet pipe before the third condenser and the second condenser. The control method includes: The opening degree of the first solenoid valve and the second solenoid valve is controlled based on the data from the third temperature sensor and the first temperature sensor.

[0015] The thermal management system and control method for a coating machine provided by this invention achieve direct heat exchange between the exhaust pipe and the intake pipe through the action of a first heat exchanger. The latent heat of the airflow in the exhaust pipe is absorbed by the first evaporator and transferred to the first condenser in the tank, thereby heating the stored hot water in the tank. The heat from the heated stored hot water in the tank is transferred to the second and third condensers through a second and a third heat pump section. Different types of coolants are used in the second and third heat pump sections to ensure operation at suitable temperatures. The circulating hot water system stores and manages the heat obtained by the first heat pump section, providing a foundation for the stable operation of the entire system. The coordinated operation of the circulating hot water system and the thermal management section enables the adjustment of various operating modes, realizing not only the recovery and utilization of latent heat but also the replenishment and storage of latent heat. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the thermal management system of the coating machine according to the first embodiment of the present invention; Figure 2 yes Figure 1 A partial magnification; Figure 3 This is a schematic diagram of the thermal management system of the coating machine according to the second embodiment of the present invention.

[0017] Reference numerals: 010-Coating head, 020-Waste hot water tank, 100-Exhaust pipe, 200-First heat exchanger, 300-Inlet pipe, 310-First temperature sensor, Third temperature sensor, 320-, 400-First heat pump section, 410-Tank body, 420-First evaporator, 430-First condenser, 440-First compressor, 500-Second heat pump section, 510-Second condenser, 520-Second compressor, 530-Second heat exchanger, 600-Third heat pump unit, 610-Third condenser, 620-Third compressor, 630-Third heat exchanger, 700-Circulating hot water system, 710-Return water pipe, 711-Second temperature sensor, 720-Water tank, 730-Water supply pipe, 731-First water pump, 800-Thermal management unit, 810-Waste hot water main pipe pair, 820-Waste hot water bypass pipe pair, 830-Heat exchange finned tube, 840-Second water pump, 850-Three-way valve, 900-Cooling box. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this specification means the presence of the stated features, integers, steps, operations, elements, units, modules, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, units, modules, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connection or wireless coupling. The term “and / or” as used herein includes all or any of the units and all combinations of one or more associated listed items.

[0020] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0021] Reference Figures 1 to 3 In one embodiment of the present invention, a thermal management system for a coating machine, corresponding to the coating head 010, includes: The exhaust pipe 100 leads out of the coating head 010; A first heat exchanger 200 is disposed on the exhaust pipe 100; The intake pipe 300 passes through the first heat exchanger 200 and the exhaust pipe 100 to form a heat exchange and is connected to the coating head 010; The first heat pump unit 400 includes a tank 410 and a first evaporator 420, a first condenser 430 and a first compressor 440 forming a cycle. The first condenser 430 is disposed inside the tank 410, and the first evaporator 420 is disposed on the exhaust pipe 100 and located downstream of the first heat exchanger 200. The second heat pump unit 500 includes a second condenser 510, a second compressor 520, and a second heat exchanger 530 forming a cycle. The second condenser 510 is disposed on the intake pipe 300 downstream of the first heat exchanger 200. The third heat pump unit 600 includes a third condenser 610, a third compressor 620 and a third heat exchanger 630 forming a cycle, wherein the third condenser 610 is disposed downstream of the second condenser 510 on the intake pipe 300. A circulating hot water system 700 includes a return water pipe 710, a water tank 720, and a supply water pipe 730 equipped with a first water pump 731. The supply water pipe 730 extends from the tank 410, connects the second heat exchanger 530 and the third heat exchanger 630 in parallel, and then returns to the water tank 720. The return water pipe 710 connects the water tank 720 and the tank 410. The thermal management unit 800 includes a waste hot water main pipe pair 810, a waste hot water bypass pipe pair 820, and a heat exchange finned tube 830. The waste hot water main pipe pair 810 is cyclically connected to the heat exchange finned tube 830 and an external waste hot water tank 020 and is equipped with a second water pump 840. The heat exchange finned tube 830 is disposed inside the tank body 410 and directly exchanges heat with the first condenser 430. The waste hot water main pipe pair 810 is equipped with two three-way valves 850 to lead out the waste hot water bypass pipe pair 820 and connect to the return water pipe 710 and the supply water pipe 730 near one end of the tank body 410, respectively.

[0022] In existing technologies, traditional heat exchange methods have significant limitations: their heat recovery efficiency is limited by the heat exchange area, airflow distribution, and thermal conductivity of the material, and it is usually difficult to achieve a high level; at the same time, when there is a large temperature difference between exhaust air and fresh air, the temperature of the preheated fresh air may still be low, which cannot fully meet the needs of subsequent heating processes, thus limiting the overall energy efficiency improvement; in the factory production process, waste hot water is often generated, but it is difficult to form a thermal management with the coating head.

[0023] The thermal management system for a coating machine provided by the present invention is configured corresponding to the coating head 010. The thermal management system for the coating machine includes an exhaust pipe 100, a first heat exchanger 200, an air inlet pipe 300, a first heat pump section 400, a second heat pump section 500, a third heat pump section 600, a circulating hot water system 700, and a thermal management section 800.

[0024] The exhaust pipe 100 leads out to the coating head 010, and exhausts the hot airflow inside the coating head 010.

[0025] The first heat exchanger 200 is disposed on the exhaust pipe 100. For example, the first heat exchanger 200 includes two interconnected passages, with the exhaust pipe 100 connected to one of the passages of the first heat exchanger 200.

[0026] The intake pipe 300 passes through the first heat exchanger 200 and forms a heat exchange with the exhaust pipe 100, and is connected to the coating head 010. For example, the intake pipe 300 is connected to another passage of the first heat exchanger 200. Through the action of the first heat exchanger 200, a direct heat exchange is formed between the exhaust pipe 100 and the intake pipe 300, and the temperature of the airflow in the exhaust pipe 100 is utilized to heat the airflow in the intake pipe 300.

[0027] The first heat pump unit 400 includes a tank 410. The first heat pump unit 400 also includes a first evaporator 420, a first condenser 430, and a first compressor 440 forming a circulation loop. To achieve heat pump operation, functional components such as expansion valves are added at appropriate locations. The first condenser 430 is disposed within the tank 410. During operation, the tank 410 contains stored hot water, which exchanges heat with the coolant in the first condenser 430. The first evaporator 420 is disposed on the exhaust pipe 100 and downstream of the first heat exchanger 200. The latent heat of the airflow in the exhaust pipe 100 is absorbed by the first evaporator 420.

[0028] The second heat pump unit 500 includes a second condenser 510, a second compressor 520, and a second heat exchanger 530 that form a circulation loop. To enable heat pump operation, functional components such as expansion valves are added at appropriate locations. The second condenser 510 is located downstream of the first heat exchanger 200 on the intake pipe 300. The second condenser 510 releases heat to heat the gas in the intake pipe 300.

[0029] The third heat pump section 600 includes a third condenser 610, a third compressor 620, and a third heat exchanger 630 forming a cycle. To enable heat pump operation, functional components such as expansion valves are added at appropriate locations. The third condenser 610 is located downstream of the second condenser 510 on the intake pipe 300. The third condenser 610 releases heat to further heat the gas in the intake pipe 300. Different types of coolants can be used in the second heat pump section 500 and the third heat pump section 600 to operate at suitable temperatures. The operating temperature of the coolant in the third heat pump section 600 is higher than that of the coolant in the second heat pump section 500, thus the third condenser 610 provides a higher heating temperature relative to the second condenser 510.

[0030] The circulating hot water system 700 includes a return pipe 710, a water tank 720, and a supply pipe 730 equipped with a first water pump 731. The type of the first water pump 731 is not limited; in some cases, the first water pump 731 may be a model that performs bidirectional pumping. The supply pipe 730 extends from the tank 410, connects the second heat exchanger 530 and the third heat exchanger 630 in parallel, and then returns to the water tank 720. The return pipe 710 connects the water tank 720 and the tank 410.

[0031] The thermal management unit 800 includes a waste hot water main pipe pair 810, a waste hot water bypass pipe pair 820, and a heat exchange finned tube 830. The waste hot water main pipe pair 810 is cyclically connected to the heat exchange finned tube 830 and an external waste hot water tank 020, and is equipped with a second water pump 840. For example, the heat exchange finned tube 830 includes a coil with fins, and the waste hot water main pipe pair 810 includes a waste hot water inlet main pipe and a waste hot water outlet main pipe. The waste hot water inlet main pipe and the waste hot water outlet main pipe are led out from the external waste hot water tank 020 and respectively connected to both ends of the coil on the heat exchange finned tube 830. The heat exchange finned tube 830 is disposed inside the tank 410 and directly exchanges heat with the first condenser 430; for example, the fin structure of the heat exchange finned tube 830 and the fin structure of the first condenser 430 are arranged in close contact. In some processes, the high temperature at the first condenser 430 can be transferred to the waste hot water in the waste hot water tank 020 through the heat exchange finned tube 830. Two three-way valves 850 are installed on the main wastewater hot water pipe 810 to lead to a wastewater hot water bypass pipe 820, which is connected to the return water pipe 710 and the supply water pipe 730 near one end of the tank 410, respectively. The three-way valves 850 are preferably electrically controlled, specifically controlling whether the wastewater hot water in the wastewater hot water tank 020 enters the heat exchange finned tube 830 or the circulating hot water system 700. In some processes, the wastewater hot water in the wastewater hot water tank 020 can enter the circulating hot water system 700 to provide an auxiliary latent heat source.

[0032] During operation, in a balanced mode, the heat obtained by the first heat exchanger 200 and the first heat pump section 400 is just right, so there is no need to use the waste hot water in the external waste hot water tank 020. The state of the three-way valve 850 is controlled, and the waste hot water bypass pipe 820 is not connected to the circulating hot water system 700. Simultaneously, the second water pump 840 is not working, and the waste hot water in the waste hot water tank 020 does not enter the heat exchange finned tube 830, thus not obtaining heat from the first condenser 430 in the first heat pump section 400. Through the action of the first heat exchanger 200, a direct heat exchange is formed between the exhaust pipe 100 and the intake pipe 300; the latent heat of the airflow in the exhaust pipe 100 is absorbed by the first evaporator 420 and transferred to the position of the first condenser 430 in the tank 410, thereby heating the stored hot water in the tank 410; the water supply pipe 730 of the circulating hot water system 700 leads out of the tank 410, connects the second heat exchanger 530 and the third heat exchanger 630 in parallel, and returns to the water tank 720, so that the heat in the heated stored hot water in the tank 410 is transferred to the second condenser 510 and the third condenser 610 through the second heat pump section 500 and the third heat pump section 600. The coolants in the second heat pump section 500 and the third heat pump section 600 are of different types, so that they can work at a suitable temperature.

[0033] Reheating Operation: If the heat obtained by the first heat exchanger 200 and the first heat pump unit 400 is insufficient, wastewater from the external wastewater tank 020 must be used. By controlling the state of the three-way valve 850, the wastewater bypass pipe 820 is connected to the circulating hot water system 700. Simultaneously, the second water pump 840 operates, allowing wastewater from the wastewater tank 020 to enter the circulating hot water system 700. Since the temperature of the wastewater is higher than that of the stored hot water, the participation rate of the wastewater can be adjusted by controlling the operating intensity of the second water pump 840 and the first water pump 731.

[0034] Heat recovery operation: When the first heat exchanger 200 and the first heat pump unit 400 receive excess heat, this excess heat can be transferred to the waste hot water in the waste hot water tank 020. The state of the three-way valve 850 is controlled, preventing the waste hot water bypass pipe 820 from connecting to the circulating hot water system 700. Simultaneously, the second water pump 840 operates, and the waste hot water in the waste hot water tank 020 enters the heat exchange finned tube 830, directly transferring heat from the coolant in the first condenser 430 to the waste hot water.

[0035] In summary, through the action of the first heat exchanger 200, direct heat exchange is formed between the exhaust pipe 100 and the intake pipe 300. The latent heat of the airflow in the exhaust pipe 100 is absorbed by the first evaporator 420 and transferred to the first condenser 430 in the tank 410, thereby heating the stored hot water in the tank 410. The heat from the heated stored hot water in the tank 410 is transferred to the second condenser 510 and the third condenser 610 through the second heat pump section 500 and the third heat pump section 600. Different types of coolants are used in the second heat pump section 500 and the third heat pump section 600, allowing them to operate at suitable temperatures. The circulating hot water system 700 stores and manages the heat obtained by the first heat pump section 400, providing a foundation for the stable operation of the entire system. Through the coordinated operation of the circulating hot water system 700 and the thermal management section 800, various operating modes are adjusted, realizing not only the recovery and utilization of latent heat but also the replenishment and storage of latent heat.

[0036] Reference Figures 1 to 2 In one embodiment, a first temperature sensor 310 is provided downstream of the third condenser 610 in the air inlet pipe 300, and a second temperature sensor 711 is provided in one end of the return water pipe 710 connected to the tank 410.

[0037] In this embodiment, the operating intensity of the second heat pump unit 500 is guided by the data from the first temperature sensor 310, and the switching of the operating mode is guided by the second temperature sensor 711. These details will be explained in detail in subsequent embodiments.

[0038] Reference Figures 1 to 2In one embodiment, the water supply pipe 730 branches into a first water supply pipe and a second water supply pipe, which are respectively connected to the second heat exchanger 530 and the third heat exchanger 630. A first solenoid valve and a second solenoid valve are respectively provided on the first water supply pipe and the second water supply pipe.

[0039] In this embodiment, controllability is improved by using a first solenoid valve and a second solenoid valve installed on the first and second water supply pipes. Specifically, adjusting the opening degree of the first and second solenoid valves can control the proportion of hot water entering the second heat exchanger 530. The first and second solenoid valves can have various structural types, such as solenoid gate valves or solenoid ball valves, performing valve functions while maintaining a simple and reliable structure.

[0040] Reference Figures 1 to 2 In one embodiment, the end of the exhaust pipe 100 away from the coating head 010 is connected to the end of the air intake pipe 300 away from the coating head 010.

[0041] In this embodiment, a portion of the gas discharged from the coating head 010 is recycled, specifically through the connection of the air inlet pipe 300 and the exhaust pipe 100. Depending on actual needs, the gas in the exhaust pipe 100 can be completely or partially recycled.

[0042] Reference Figures 1 to 2 In one embodiment, a cooling box 900 is connected between the exhaust pipe 100 and the intake pipe 300.

[0043] In this embodiment, considering that some coating heads 010 use organic solvents, the gas in the exhaust pipe 100 contains solvent vapors that cannot be directly recovered and reused. Therefore, a cooling box 900 is connected between the exhaust pipe 100 and the inlet pipe 300. The cooling box 900 cools the gas in the exhaust pipe 100, recovering the organic solvents in the gas. A surface cooler can be installed in the cooling box 900 to achieve the cooling effect, thereby collecting the condensed solvent.

[0044] In one embodiment, the water supply pipe 730 is connected to the first water supply pipe and the second water supply pipe via a diverter-type three-way valve.

[0045] In this embodiment, the flow ratio between the first water supply pipe and the second water supply pipe is achieved by adjusting a flow-dividing three-way valve.

[0046] Reference Figure 3 In one embodiment, the heat exchange finned tube 830 and the first condenser 430 are an integral structure.

[0047] In the aforementioned embodiments, the method of heat exchange between the heat exchange finned tube 830 and the first condenser 430 was not limited. In this embodiment, the heat exchange finned tube 830 and the first condenser 430 are configured as an integrated structure, which is simple and efficient. Generally, the structure of condensers and evaporators consists of coils with fins. The coils provide the basis for refrigerant conduction, while the fins increase the heat exchange area. One coil structure is provided for the heat exchange finned tube 830, and another coil structure is provided for the first condenser 430. The two coil structures share a set of fins, thus achieving more efficient heat conduction while simplifying the structure.

[0048] In one embodiment, the refrigerant used in the second heat pump unit 500 is R142b, and the refrigerant used in the third heat pump unit 600 is R1233zd.

[0049] In this embodiment, the second heat pump section 500 uses R142b as a coolant, with a boiling point of -9.25°C and a critical temperature of 106.8°C. The third heat pump section 600 uses R1233zd as a coolant, with a boiling point of 18.3°C and a critical temperature of 165.5°C.

[0050] The present invention also provides a control method applied to the above-mentioned thermal management system of the coating machine, comprising: S1. Based on the data from the first temperature sensor 310, control the operating intensity of the second compressor 520 and the third compressor 620; S2. Real-time acquisition of data from the second temperature sensor 711 to obtain the residual temperature of the stored hot water; S3. If the residual temperature of the stored hot water is between B and C degrees, the thermal management system of the coating machine is switched to the balanced working mode. In the balanced working mode, the three-way valve 850 connects the waste hot water main pipe 810 with the heat exchange finned tube 830, the second water pump 840 stops working, and the first water pump 731 starts working. S4. If the residual temperature of the stored hot water is between A and B degrees, the thermal management system of the coating machine is switched to the supplementary heating mode. In the supplementary heating mode, the three-way valve 850 connects the waste hot water main pipe 810 with the circulating hot water system 700, and the second water pump 840 is in operation. S5. If the residual temperature of the stored hot water is between C and D degrees, the thermal management system of the coating machine is switched to the heat recovery mode. In the heat recovery mode, the three-way valve 850 connects the waste hot water main pipe 810 with the heat exchange finned tube 830, the second water pump 840 stops working, and the first water pump 731 starts working. Among them, A <B<C<D。

[0051] In this embodiment, the balanced operation mode: when the heat obtained by the first heat exchanger 200 and the first heat pump unit 400 is just right, there is no need to use the waste hot water in the external waste hot water tank 020 at this time. Control the state of the three-way valve 850, and the waste hot water bypass pair 820 is not connected to the circulating hot water system 700. At the same time, the second water pump 840 does not work, and the waste hot water in the waste hot water tank 020 does not enter the heat exchange finned tube 830, and thus does not obtain the heat at the first condenser 430 in the first heat pump unit 400. Through the action of the first heat exchanger 200, a direct heat exchange is formed between the exhaust pipe 100 and the intake pipe 300; the latent heat of the air flow in the exhaust pipe 100 is absorbed by the first evaporator 420 and transferred to the position of the first condenser 430 in the tank body 410, and thus the stored hot water in the tank body 410 can be heated; the water supply pipe 730 of the circulating hot water system 700 leads out of the tank body 410, and the second heat exchanger 530 and the third heat exchanger 630 are connected in parallel and then return to the water tank 720, so that the heat in the heated stored hot water in the tank body 410 is transferred to the second condenser 510 and the third condenser 610 through the second heat pump unit 500 and the third heat pump unit 600. Different types of coolants are used in the second heat pump unit 500 and the third heat pump unit 600, so that they can work at appropriate temperatures.

[0052] Heat supplement operation mode: when the heat obtained by the first heat exchanger 200 and the first heat pump unit 400 is insufficient, the waste hot water in the external waste hot water tank 020 needs to be used at this time. Control the state of the three-way valve 850, and the waste hot water bypass pair 820 is connected to the circulating hot water system 700. At the same time, the second water pump 840 works, and the waste hot water in the waste hot water tank 020 enters the circulating hot water system 700. Since the temperature of the waste hot water is higher than that of the stored hot water, the participation degree of the waste hot water can also be adjusted by controlling the working intensity of the second water pump 840 and the first water pump 731.

[0053] Heat recovery operation mode: when the heat obtained by the first heat exchanger 200 and the first heat pump unit 400 is excessive, the excess heat can be transferred to the waste hot water in the waste hot water tank 020 at this time. Control the state of the three-way valve 850, and the waste hot water bypass pair 820 is not connected to the circulating hot water system 700. At the same time, the second water pump 840 works, and the waste hot water in the waste hot water tank 020 enters the heat exchange finned tube 830, and the heat of the coolant in the first condenser 430 is directly transmitted to the waste hot water.

[0054] The type of the three-way valve 850 is preferably a motor-driven ball valve type. In the numerical relationship, A < B < C < D. For example, A is 45 degrees, B is 50 degrees, C is 55 degrees, and D is 60 degrees. The above numerical relationship is designed and adjusted according to the working intensity of the coating head 010.

[0055] In one embodiment, in step S4, the operating intensity of the first water pump 731 and the second water pump 840 is adjusted according to the residual temperature of the stored hot water.

[0056] In this embodiment, considering that the working intensity of the first water pump 731 and the second water pump 840 affects the degree of waste hot water introduction into the waste hot water tank 020, the working intensity of the first water pump 731 and the second water pump 840 can be adjusted according to the residual temperature of the stored hot water to regulate the working state of the entire system and maximize its efficiency. For example, when the residual temperature of the stored hot water is close to B degrees, the working intensity of the second water pump 840 is reduced and the working intensity of the first water pump 731 is increased, thus reducing the participation of the stored hot water; when the residual temperature of the stored hot water is close to A degrees, the working intensity of the second water pump 840 is increased and the working intensity of the first water pump 731 is increased, thus increasing the participation of the stored hot water.

[0057] In one embodiment, the water supply pipe 730 branches into a first water supply pipe and a second water supply pipe, which are then connected to the second heat exchanger 530 and the third heat exchanger 630, respectively. A first solenoid valve and a second solenoid valve are respectively installed on the first water supply pipe and the second water supply pipe. A third temperature sensor 320 is installed on the air inlet pipe 300 before the third condenser 610 and the second condenser 510. The control method includes: The opening degree of the first solenoid valve and the second solenoid valve is controlled based on the data from the third temperature sensor 320 and the first temperature sensor 310.

[0058] In this embodiment, the airflow is used to determine the heating state of the second condenser 510 and the third heat pump unit 600 based on the data from the third temperature sensor 320 and the first temperature sensor 310. Then, the working state is adjusted by adjusting the first solenoid valve and the second solenoid valve.

[0059] In summary, the coating machine thermal management system and control method provided by this invention achieve direct heat exchange between the exhaust pipe 100 and the inlet pipe 300 through the action of the first heat exchanger 200. The latent heat of the airflow in the exhaust pipe 100 is absorbed by the first evaporator 420 and transferred to the first condenser 430 in the tank 410, thereby heating the stored hot water in the tank 410. The heat from the heated stored hot water in the tank 410 is transferred to the second condenser 510 and the third condenser 610 through the second heat pump unit 500 and the third heat pump unit 600. Different types of coolants are used in the second heat pump unit 500 and the third heat pump unit 600, allowing them to operate at suitable temperatures. The circulating hot water system 700 stores and manages the heat obtained by the first heat pump unit 400, providing a foundation for the stable operation of the entire system. The coordinated operation of the circulating hot water system 700 and the thermal management unit 800 enables the adjustment of various operating modes, realizing not only the recovery and utilization of latent heat but also the replenishment and storage of latent heat.

[0060] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A thermal management system for a coating machine, configured corresponding to the coating machine head, characterized in that, include: The exhaust pipe leads out of the coating head; A first heat exchanger is disposed on the exhaust pipe; The air intake pipe passes through the first heat exchanger and forms a heat exchange with the exhaust pipe, and is connected to the coating head; The first heat pump unit includes a tank and a first evaporator, a first condenser and a first compressor forming a cycle. The first condenser is disposed in the tank, and the first evaporator is disposed on the exhaust pipe and located downstream of the first heat exchanger. The second heat pump section includes a second condenser, a second compressor, and a second heat exchanger that form a cycle, with the second condenser located downstream of the first heat exchanger on the intake pipe. The third heat pump section includes a third condenser, a third compressor, and a third heat exchanger that form a cycle, wherein the third condenser is located downstream of the second condenser on the intake pipe; A circulating hot water system includes a return pipe, a water tank, and a supply pipe equipped with a first water pump. The supply pipe extends from the tank, connects the second heat exchanger and the third heat exchanger in parallel, and then returns to the water tank. The return pipe connects the water tank and the tank. The thermal management unit includes a waste hot water main pipe pair, a waste hot water bypass pipe pair, and a heat exchange finned tube. The waste hot water main pipe pair is circulatedly connected to the heat exchange finned tube and an external waste hot water tank and is equipped with a second water pump. The heat exchange finned tube is located inside the tank and directly exchanges heat with the first condenser. The waste hot water main pipe pair is equipped with two three-way valves to lead out the waste hot water bypass pipe pair and connect to the return water pipe and the supply water pipe near one end of the tank, respectively.

2. The thermal management system for the coating machine according to claim 1, characterized in that, A first temperature sensor is installed downstream of the third condenser inside the air intake pipe, and a second temperature sensor is installed at one end of the return water pipe connected to the tank.

3. The thermal management system for the coating machine according to claim 1, characterized in that, The water supply pipe branches into a first water supply pipe and a second water supply pipe, which are then connected to the second heat exchanger and the third heat exchanger, respectively. A first solenoid valve and a second solenoid valve are respectively installed on the first water supply pipe and the second water supply pipe.

4. The thermal management system for a coating machine according to claim 1, characterized in that, The water supply pipe is connected to the first water supply pipe and the second water supply pipe via a diverter-type three-way valve.

5. The thermal management system for a coating machine according to claim 1, characterized in that, The heat exchange finned tube is an integral structure with the first condenser.

6. The thermal management system for a coating machine according to claim 1, characterized in that, The refrigerant used in the second heat pump section is R142b, and the refrigerant used in the third heat pump section is R1233zd.

7. The thermal management system for a coating machine according to claim 1, characterized in that, The end of the exhaust pipe away from the coating head is connected to the end of the intake pipe away from the coating head.

8. A control method applied to the thermal management system of the coating machine as described in claim 2, characterized in that, include: S1. Based on the data from the first temperature sensor, control the operating intensity of the second compressor and the third compressor; S2. Real-time acquisition of data from the second temperature sensor to obtain the residual temperature of the stored hot water; S3. If the residual temperature of the stored hot water is between B and C degrees, the thermal management system of the coating machine is switched to the balanced working mode. In the balanced working mode, the three-way valve connects the waste hot water main pipe to the heat exchange finned tube, the second water pump stops working, and the first water pump starts working. S4. If the residual temperature of the stored hot water is between A and B degrees, the thermal management system of the coating machine is switched to the supplementary heating mode. In the supplementary heating mode, the three-way valve connects the waste hot water main pipe to the circulating hot water system, and the second water pump is activated. S5. If the residual temperature of the stored hot water is between C and D degrees, the thermal management system of the coating machine is switched to the heat recovery mode. In the heat recovery mode, the three-way valve connects the waste hot water main pipe to the heat exchange finned tube, the second water pump stops working, and the first water pump starts working. Among them, A <B<C<D。 9. The control method according to claim 8, characterized in that, In step S4, the operating intensity of the first and second water pumps is adjusted according to the residual temperature of the stored hot water.

10. The control method according to claim 8, characterized in that, The water supply pipe branches into a first water supply pipe and a second water supply pipe, which are then connected to the second heat exchanger and the third heat exchanger, respectively. A first solenoid valve and a second solenoid valve are respectively installed on the first water supply pipe and the second water supply pipe. A third temperature sensor is installed on the air inlet pipe before the third condenser and the second condenser. The control method includes: The opening degree of the first solenoid valve and the second solenoid valve is controlled based on the data from the third temperature sensor and the first temperature sensor.

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