Three-stage evaporator refrigerating system
By switching between solenoid valves controlled by a three-stage evaporator refrigeration system and a humidity sensor, the problems of evaporator frosting and condensation are solved, achieving efficient humidity control and reduced energy consumption, extending the defrosting interval, and improving heat exchange efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- AUCMA
- Filing Date
- 2025-06-27
- Publication Date
- 2026-05-01
AI Technical Summary
In traditional refrigeration systems, frost and condensation on the evaporator surface are serious problems, especially in high humidity environments, which affect heat exchange efficiency and increase energy consumption. Frequent defrosting also significantly increases energy consumption, and there is a lack of humidity control capabilities.
A three-stage evaporator refrigeration system is adopted, including a condensation evaporator, a frosting evaporator and a main evaporator. The refrigerant flow direction is switched by a solenoid valve controlled by a humidity sensor. Condensation evaporators and frosting evaporators are set at the air inlet and air outlet respectively. Combined with a four-way valve to switch the refrigerant flow direction, heat defrosting is achieved, reducing moisture condensation and energy consumption.
It significantly reduces water vapor condensation on the main evaporator, extends the defrosting interval, reduces energy consumption, reduces temperature fluctuations, and improves heat exchange efficiency.
Smart Images
Figure CN224188791U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of refrigeration system technology, and in particular to a three-stage evaporator refrigeration system and its refrigeration equipment. Background Technology
[0002] In traditional refrigeration systems, the problem of frost and condensation on the evaporator surface has long existed. Especially in high humidity environments, when a single evaporator cools the air, the moisture in the air will condense directly on the evaporator. Especially when the cabinet door is frequently opened and closed, the moisture in the air is prone to frost due to the low temperature, which will adhere to the evaporator and block the air duct, thereby affecting the heat exchange effect and causing the refrigeration equipment to consume more energy. Frequent defrosting will significantly increase energy consumption. A single evaporator lacks the ability to adjust according to humidity and can only maintain the heat exchange effect through frequent defrosting. Utility Model Content
[0003] To address the problem of existing technologies where a single evaporator lacks independent humidity control capabilities, this invention provides a three-stage evaporator refrigeration system, comprising a compressor, a condenser, a first refrigeration circuit, a second refrigeration circuit, and a humidity sensor. The first refrigeration circuit includes a first throttling device, a main evaporator, and a frosting evaporator arranged sequentially. The second refrigeration circuit includes a solenoid valve, a second throttling device, and a condensation evaporator arranged sequentially. The condensation evaporator, the frosting evaporator, and the main evaporator are sequentially arranged in an air duct. The humidity sensor and the solenoid valve are electrically connected to a controller, which opens and closes the solenoid valve based on the detection result of the humidity sensor.
[0004] Specifically, the first refrigeration circuit and the second refrigeration circuit are connected to the outlet of the condenser. The outlet of the compressor is provided with a return pipe, and the inlet of the return pipe is provided with a four-way valve. The four-way valve is electrically connected to the controller to switch the outlet of the compressor to connect with the inlet of the condenser or with the outlet of the first refrigeration circuit.
[0005] Specifically, the four-way valve has interface A1, interface A2, interface A3 and interface A4. Interface A1 is connected to the outlet of the compressor, interface A2 is connected to the inlet of the condenser, interface A3 is connected to the inlet of the return pipeline, and interface A4 is connected to the outlet of the first refrigeration circuit.
[0006] Specifically, during cooling, interface A1 is connected to interface A2, and interface A3 is connected to interface A4; during defrosting, interface A1 is connected to interface A4, and interface A2 is connected to interface A3.
[0007] Specifically, a gas-liquid separator is installed in the return pipeline, and the outlet of the gas-liquid separator is connected to the inlet of the compressor.
[0008] Specifically, the outlet of the second refrigeration circuit is connected to the return pipeline.
[0009] Specifically, a first three-way valve is provided between the first throttling device and the main evaporator, and a second three-way valve is provided between the second throttling device and the main evaporator. The first three-way valve and the second three-way valve are electrically connected to the controller.
[0010] Specifically, the first three-way valve has interfaces B1, B2, and B3. Interface B1 is connected to the outlet of the first throttling device, interface B2 is connected to the inlet of the first throttling device, and interface B3 is connected to the inlet of the main evaporator. The second three-way valve has interfaces C1, C2, and C3. Interface C1 is connected to the outlet of the main evaporator, interface C2 is connected to the inlet of the frosting evaporator, and interface C3 is connected to the outlet of the first throttling device.
[0011] Specifically, the pressure drop of the first throttling device is greater than the pressure drop of the second throttling device.
[0012] Specifically, the condensation evaporator and the frosting evaporator are arranged sequentially at the air inlet, and the main evaporator is arranged at the air outlet.
[0013] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0014] 1. This utility model sets up a condensation evaporator and a frosting evaporator at the air inlet and a main evaporator at the air outlet of the air duct. When the humidity in the air is high, the moisture in the air is separated and condensed through the condensation evaporator and the frosting evaporator, which effectively reduces the condensation of water vapor on the main evaporator, significantly reduces the impact of frost on the heat exchange effect of the main evaporator, and extends the defrosting interval of the main evaporator.
[0015] 2. This utility model uses a four-way valve to switch the refrigerant flow direction for thermal defrosting, which significantly reduces energy consumption compared with traditional electric heating defrosting. Moreover, the defrosting process mainly focuses on defrosting the frosted evaporator, reducing temperature fluctuations in the refrigeration equipment caused by the defrosting process. Attached Figure Description
[0016] Figure 1 This is a schematic diagram showing the location of the evaporator in this utility model.
[0017] Figure 2 This is a schematic diagram of the refrigeration system of this utility model;
[0018] Figure 3 This is a schematic diagram of the refrigeration system of this utility model.
[0019] Figure 4 This is a schematic diagram of the defrosting refrigeration system of this utility model.
[0020] Reference numerals: 1. Compressor; 2. Condenser; 3. First throttling device; 4. Main evaporator; 5. Frosting evaporator; 6. Solenoid valve; 7. Second throttling device; 8. Condensation evaporator; 9. Gas-liquid separator; 10. Air duct; 11. Air inlet; 12. Air outlet; A. Four-way valve; B. First three-way valve; C. Second three-way valve. Detailed Implementation
[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. The specific implementation of the present utility model will be described in detail below with reference to specific embodiments.
[0022] 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0023] As shown in the figure, this utility model provides a three-stage evaporator refrigeration system, including a compressor 1, a condenser 2, a first refrigeration circuit, a second refrigeration circuit, and a humidity sensor. The first refrigeration circuit includes a first throttling device 3, a main evaporator 4, and a frosting evaporator 5 arranged sequentially. The second refrigeration circuit includes a solenoid valve 6, a second throttling device 7, and a condensation evaporator 8 arranged sequentially. The condensation evaporator 8, the frosting evaporator 5, and the main evaporator 4 are arranged sequentially in an air duct 10. The humidity sensor and the solenoid valve 6 are electrically connected to a controller, which controls the opening and closing of the evaporator based on the detection result of the humidity sensor. This refrigeration system is applicable to refrigerators, freezers, cold storage, and constant temperature and humidity systems for precision instruments. By using the condensation evaporator 8 and the frosting evaporator 5 to condense and remove moisture from the air, water vapor is prevented from condensing into the main evaporator 4, significantly extending the defrosting interval of the main evaporator 4.
[0024] The condensation evaporator 8 and the frosting evaporator 5 are sequentially arranged at the air inlet 11 of the air duct 10, and the main evaporator 4 is arranged at the air outlet 12 of the air duct 10. Water collection boxes for collecting condensate are respectively installed below the condensation evaporator 8, the frosting evaporator 5, and the main evaporator 4. The condensation evaporator 8 is located at the air inlet 11 at the bottom of the refrigeration equipment, and its temperature is maintained at approximately 0℃-5℃. It precipitates moisture from the air through a low-temperature section. The frosting evaporator 5 is located behind the condensation evaporator 8 and is a small-sized evaporator connected in series with the main evaporator 4. Its temperature is close to that of the main evaporator 4, and it pre-cools the air entering the air duct 10, freezing the residual water vapor from the condensation evaporator 8 into a frost layer in the frosting evaporator 5. The main evaporator 4 bears the main cooling load of the refrigeration system. The condensation evaporator 8 and the frosting evaporator 5 significantly reduce the condensation of moisture on the main evaporator 4, significantly extending the defrosting interval of the main evaporator 4.
[0025] Specifically, such as Figure 2 The diagram shows the schematic of the refrigeration system of this utility model. A four-way valve A is provided at the outlet of the compressor 1. The four-way valve A has an interface A1, an interface A2, an interface A3 and an interface A4. Interface A1 of the four-way valve A is connected to the outlet of the compressor 1, interface A2 is connected to the condenser 2, the outlet of the first refrigeration circuit is connected to interface A4, and interface A3 is connected to the inlet of the return pipeline. The four-way valve A switches the flow direction of the refrigerant, so that the refrigerant is cooled or defrosted in the evaporator.
[0026] The outlet of condenser 2 is connected to a first refrigeration circuit and a second refrigeration circuit. The first refrigeration circuit includes a first throttling device 3, a main evaporator 4, and a frosting evaporator 5 arranged sequentially. The first throttling device 3 has a large pressure drop. During refrigeration, the medium-temperature, high-pressure liquid refrigerant expands into a low-temperature, low-pressure gas after the pressure drop, significantly cooling the refrigerant to the target temperature of the refrigeration equipment, such as -20℃ to -25℃. The refrigerant passes sequentially through the main evaporator 4 and the frosting evaporator 5 to provide refrigeration for the refrigeration equipment. A first three-way valve B is installed between the first throttling device 3 and the main evaporator 4, and a second three-way valve C is installed between the second throttling device 7 and the main evaporator 4. The first three-way valve B has ports B1, B2, and B3. Port B1 is connected to the outlet of the first throttling device 3, port B2 is connected to the inlet of the first throttling device 3, and port B3 is connected to the inlet of the main evaporator 4. The second three-way valve C has ports C1, C2, and C3. Port C1 is connected to the outlet of the main evaporator 4, port C2 is connected to the inlet of the frosting evaporator 5, and port C3 is connected to the outlet of the first throttling device 3. The refrigerant is connected to the return line through port A3 via the four-way valve A, allowing the refrigerant to circulate and be delivered to the compressor 1.
[0027] The second refrigeration circuit includes a solenoid valve 6, a second throttling device 7, and a condenser evaporator 8. The inlet of the solenoid valve 6 is connected to the outlet of the condenser 2, and the outlet of the solenoid valve 6 is connected to the inlet of the first throttling device 3. The opening degree of the solenoid valve 6 is controllable, allowing some refrigerant to enter the second refrigeration circuit. The second throttling device 7 has a small pressure drop, causing the medium-temperature, high-pressure liquid refrigerant to expand into a low-temperature, low-pressure gas, slightly cooling the refrigerant and maintaining the temperature of the condenser evaporator 8 within the range of 0℃-5℃, thus achieving the purpose of condensation. The outlet of the condenser evaporator 8 is connected to the return pipeline, allowing the refrigerant to be circulated back to the compressor 1.
[0028] A gas-liquid separator 9 is installed in the return pipeline. The outlet of the gas-liquid separator 9 is connected to the inlet of the compressor 1 to prevent liquid refrigerant from flowing into the compressor 1 and causing liquid slugging damage to the compressor 1.
[0029] A pipeline connected in parallel with the main evaporator 4 is installed between the second three-way valve C and the first throttling device 3. Since a large amount of moisture in the air has been precipitated after passing through the condensation evaporator 8 and the frosting evaporator 5, there is less frost adhering to the main evaporator 4. Only one defrosting of the main evaporator 4 is required over a long period of time. The joint defrosting of the main evaporator 4 and the frosting evaporator 5 is defined as large-cycle defrosting, and the process of defrosting only the frosting evaporator 5 is defined as small-cycle defrosting. During small-cycle defrosting, the entire air duct 10 is first preheated to prevent the water vapor generated during the defrosting process of the frosting evaporator 5 from re-condensing on the main evaporator 4. Then, the first three-way valve B and the second three-way valve C are adjusted so that the refrigerant bypasses the main evaporator 4 and only defrosts the frosting evaporator 5, reducing the temperature fluctuations caused by the hot defrosting process to the refrigeration equipment. After the C1 port of the second three-way valve C is closed, the B2 port of the first three-way valve B is opened to prevent the high-temperature liquid refrigerant remaining in the main evaporator 4 from vaporizing and causing excessive pressure inside the main evaporator 4.
[0030] The first three-way valve B, the second three-way valve C, the solenoid valve 6, and the four-way valve A are electrically connected to the controller. A humidity sensor, also electrically connected to the controller, is installed inside the refrigeration equipment to detect the humidity of the air entering the equipment. The controller has a preset humidity threshold for activating the condenser evaporator 8. When the humidity sensor detects that the humidity of the air entering the refrigeration equipment exceeds the preset threshold, the controller controls the solenoid valve 6 to open, allowing refrigerant to enter the condenser evaporator 8 through the second throttling device 7, thus reducing the humidity in the air. The defrosting process can be achieved by installing a temperature sensor on the evaporator surface, allowing the controller to defrost based on the evaporator temperature. Alternatively, the controller can periodically control the evaporator to defrost, enabling short-cycle or long-cycle defrosting.
[0031] During cooling, ports A1 and A2 of the four-way valve A are connected, and ports A3 and A4 are connected. The refrigerant flows in the forward direction, passing through compressor 1, condenser 2, the throttling device, and evaporator in sequence, finally returning to compressor 1. During defrosting, ports A1 and A4 of the four-way valve A are connected, and ports A2 and A3 are connected. The refrigerant flows in the reverse direction, passing through compressor 1, evaporator, throttling device, and condenser 2 in sequence, finally returning to compressor 1.
[0032] Based on external environmental factors and internal frost conditions, the refrigeration system divides refrigeration control into high humidity refrigeration control and low humidity refrigeration control, and defrosting control into short-cycle defrosting control and long-cycle defrosting control.
[0033] During the refrigeration process, four-way valve A allows the refrigerant to flow in the forward direction. When the humidity sensor detects high humidity, solenoid valve 6 controls its opening to allow some refrigerant to enter the second refrigeration circuit. Interface B2 closes, while interfaces B1 and B3 open. Interface C2 closes, while interfaces C1 and C3 open. The temperature of the condenser evaporator 8 is maintained within the range of 0℃-5℃, condensing moisture from the air. The main evaporator 4 and the frosting evaporator 5 cool the refrigeration equipment. When the humidity sensor inside the refrigeration equipment detects low humidity, solenoid valve 6 closes, interface B2 closes, while interfaces B1 and B3 open. Interface C2 closes, while interfaces C1 and C3 open. The refrigerant then passes sequentially through the main evaporator 4 and the frosting evaporator 5 to cool the refrigeration equipment.
[0034] During short-cycle defrosting, four-way valve A reverses the refrigerant flow, solenoid valve 6 is closed, and initially, port B2 is briefly closed while ports B1 and B3 are open, port C3 is closed, and ports C1 and C2 are open to preheat the entire air duct 10. Subsequently, port C1 is closed, and ports C2 and C3 are open, followed by port B1 being closed and ports B2 and B3 being open, until the frost on the surface of the frosted evaporator 5 is completely melted. During long-cycle defrosting, four-way valve A reverses the refrigerant flow, solenoid valve 6 is closed, port B2 is closed, and ports B1 and B3 are open, followed by port C3 being closed, and ports C1 and C2 are open, until the frost on the surfaces of the main evaporator 4 and the frosted evaporator 5 is completely melted.
[0035] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from its technical solution shall still fall within the protection scope of this utility model.
Claims
1. A three-stage evaporator refrigeration system, characterized in that, The system includes a compressor (1), a condenser (2), a first refrigeration circuit, a second refrigeration circuit, and a humidity sensor. The first refrigeration circuit includes a first throttling device (3), a main evaporator (4), and a frosting evaporator (5) arranged in sequence. The second refrigeration circuit includes a solenoid valve (6), a second throttling device (7), and a condensation evaporator (8) arranged in sequence. The condensation evaporator (8), the frosting evaporator (5), and the main evaporator (4) are arranged in sequence in the air duct (10). The humidity sensor and the solenoid valve (6) are electrically connected to the controller. The controller opens and closes the solenoid valve based on the detection result of the humidity sensor.
2. The three-stage evaporator refrigeration system according to claim 1, characterized in that, The first refrigeration circuit and the second refrigeration circuit are connected to the outlet of the condenser (2). The outlet of the compressor (1) is provided with a return pipe. The inlet of the return pipe is provided with a four-way valve (A). The four-way valve (A) is electrically connected to the controller to switch the outlet of the compressor (1) to be connected to the inlet of the condenser (2) or to the outlet of the first refrigeration circuit.
3. The three-stage evaporator refrigeration system according to claim 2, characterized in that, The four-way valve (A) has interface A1, interface A2, interface A3 and interface A4. Interface A1 is connected to the outlet of the compressor (1), interface A2 is connected to the inlet of the condenser (2), interface A3 is connected to the inlet of the return pipeline, and interface A4 is connected to the outlet of the first refrigeration circuit.
4. The three-stage evaporator refrigeration system according to claim 3, characterized in that, During cooling, interface A1 is connected to interface A2, and interface A3 is connected to interface A4; during defrosting, interface A1 is connected to interface A4, and interface A2 is connected to interface A3.
5. The three-stage evaporator refrigeration system according to claim 2, characterized in that, A gas-liquid separator (9) is provided in the return pipeline, and the outlet of the gas-liquid separator (9) is connected to the inlet of the compressor (1).
6. The three-stage evaporator refrigeration system according to claim 2, characterized in that, The outlet of the second refrigeration circuit is connected to the return pipeline.
7. The three-stage evaporator refrigeration system according to claim 1, characterized in that, A first three-way valve (B) is provided between the first throttling device (3) and the main evaporator (4), and a second three-way valve (C) is provided between the second throttling device (7) and the main evaporator (4). The first three-way valve (B) and the second three-way valve (C) are electrically connected to the controller.
8. The three-stage evaporator refrigeration system according to claim 7, characterized in that, The first three-way valve (B) has interfaces B1, B2 and B3. Interface B1 is connected to the outlet of the first throttling device (3), interface B2 is connected to the inlet of the first throttling device (3), and interface B3 is connected to the inlet of the main evaporator (4). The second three-way valve (C) has interfaces C1, C2 and C3. Interface C1 is connected to the outlet of the main evaporator (4), interface C2 is connected to the inlet of the frosting evaporator (5), and interface C3 is connected to the outlet of the first throttling device (3).
9. The three-stage evaporator refrigeration system according to claim 1, characterized in that, The pressure drop of the first throttling device (3) is greater than the pressure drop of the second throttling device (7).
10. The three-stage evaporator refrigeration system according to claim 1, characterized in that, The condensation evaporator (8) and the frosting evaporator (5) are arranged sequentially at the air inlet (11), and the main evaporator (4) is arranged at the air outlet (12).