A high-efficiency heat exchange air conditioning unit and method based on secondary utilization of low-temperature refrigerant

Abstract

The present invention relates to the technical field of air condensation heat exchange equipment, and specifically to a high-efficiency heat exchange air conditioning unit based on the secondary utilization of low-temperature refrigerant and a method thereof. The unit includes a compressor, a condenser, an evaporator and an expansion throttle valve, wherein a liquid storage tank is arranged between the evaporator and the expansion throttle valve, and a first return pipe is arranged on the evaporator; a cooling pipe is connected to the bottom of the condenser, one end of the cooling pipe is connected to the liquid storage tank, and the other end is connected to a fourth delivery pipe. By arranging a liquid storage tank and a first return pipe between the expansion throttle valve and the evaporator, it is possible to recover the unvaporized liquid refrigerant and avoid damage to the compressor caused by liquid hammer; at the same time, the low-temperature refrigerant in the liquid storage tank is used to exchange heat with the refrigerant at the bottom of the condenser, which effectively reduces the temperature of the condenser, reduces the burden on the compressor, and improves the operating efficiency and stability of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of air condensation exchange equipment, and in particular to a high-efficiency heat exchange air conditioning unit and method based on secondary utilization of low-temperature refrigerant. Background Art

[0002] Cabinet air conditioners are increasingly used in the fields of equipment heat dissipation and indoor cooling. However, traditional fan heat dissipation methods can no longer meet the needs of modern equipment. Existing cabinet air conditioning systems mainly use compressors to compress refrigerants, condense and release heat, and then absorb heat through evaporators to reduce the ambient temperature. From the refrigeration principle of existing cabinet air conditioners, the higher the ambient temperature around the air intake of the air conditioner, the greater the working pressure of the system and the energy consumption. Especially in the high temperature environment in summer, the operating frequency of the compressor increases, and the power consumption also increases, which increases the burden on the power system and is not conducive to the continuous and safe operation of the cabinet air conditioner. Therefore, improving the working environment of the condenser is crucial to improving the working efficiency of the cabinet air conditioner.

[0003] Chinese patent CN112268314B discloses a high-efficiency heat exchange air conditioning unit, which includes components such as a shell, a compressor, an internal circulation refrigeration device, and an external circulation heat dissipation device, and cooperates with a multi-layer parallel flow evaporator and a double-layer cooling structure condenser to adjust the refrigerant circulation route to achieve the secondary utilization of low-temperature refrigerant, thereby effectively reducing the ambient temperature around the condenser and preventing liquid refrigerant from mistakenly entering the compressor. However, after the refrigerant in this patent passes through the condenser, it is directly introduced into the condenser for heat dissipation. This method will cause the temperature of the condenser to fluctuate greatly. Due to changes in the external ambient temperature and the internal temperature of the condenser, the operating temperature range of the condenser will become unstable, which directly affects the heat exchange effect. The drastic fluctuations in the condenser temperature not only reduce the overall heat exchange efficiency of the system, but may also cause the system to have inconsistent cooling effects under different load conditions, thereby affecting the stability and efficiency of the cabinet air conditioner. Summary of the invention

[0004] In view of the above problems, a high-efficiency heat exchange air-conditioning unit and method based on the secondary utilization of low-temperature refrigerant are provided. The present invention realizes the recovery of unvaporized liquid refrigerant and avoids liquid hammer damage to the compressor by arranging a liquid storage tank and a first reflux pipe between the expansion throttle valve and the evaporator. At the same time, the low-temperature refrigerant in the liquid storage tank is used to exchange heat with the refrigerant at the bottom of the condenser to reduce the condenser temperature, reduce the compressor load, and improve the system operation efficiency and stability.

[0005] In order to solve the problems of the prior art, the present invention provides a high-efficiency heat exchange air-conditioning unit based on the secondary utilization of low-temperature refrigerant, comprising an external circulation cabinet and an internal circulation cabinet, wherein a compressor and a condenser are arranged in the external circulation cabinet, an evaporator is arranged in the internal circulation cabinet, an expansion throttle valve is arranged between the condenser and the evaporator, the condenser has a first delivery pipe connected to the compressor, and a second delivery pipe connected to the expansion throttle valve; the evaporator and the compressor are connected by a third delivery pipe, and the evaporator is connected to the expansion throttle valve by a fourth delivery pipe; a liquid storage tank connected to the fourth delivery pipe is arranged between the evaporator and the expansion throttle valve, and the liquid storage tank is used to store low-temperature and low-pressure liquid refrigerant; a first reflux pipe for conveying the unvaporized liquid refrigerant in the evaporator to the liquid storage tank is arranged on the evaporator; a cooling pipe is wound around the second delivery pipe, one end of the cooling pipe is connected to the liquid storage tank, and the other end of the cooling pipe is connected to the fourth delivery pipe, so that the low-temperature refrigerant in the liquid storage tank forms a circulation loop through the cooling pipe, thereby reducing the temperature of the liquid refrigerant at the bottom of the condenser.

[0006] Preferably, the second delivery pipe is arranged at the bottom of the condenser, and the second delivery pipe is a U-shaped structure, and the cooling pipe is spirally wound around the second delivery pipe.

[0007] Preferably, a distribution valve for distributing the liquid refrigerant and connected to the expansion throttle valve is also provided next to the expansion throttle valve, and a first branch is provided on the fourth delivery pipe, the first branch is used to direct the liquid refrigerant to the liquid storage tank, and a first solenoid valve is provided on the first branch.

[0008] Preferably, a capillary tube capable of cooling the refrigerant is provided between the cooling tube and the distribution valve, the capillary tube has a spiral structure, one end of the capillary tube is connected to the distribution valve, and the other end of the capillary tube is connected to the cooling tube.

[0009] Preferably, an annular cylinder with an opening on the top is provided in the liquid storage tank, and the annular cylinder divides the interior of the liquid storage tank into a liquid storage chamber and a liquid discharge chamber. The first return pipe extends to the bottom of the liquid storage tank and is connected with the interior of the liquid storage chamber, and the first return pipe of the evaporator is provided with a first one-way valve; a liquid delivery pump is provided on the liquid discharge chamber, and a second branch is also provided on the liquid delivery pump. The second branch is used to guide the refrigerant out of the liquid discharge chamber to the fourth delivery pipe, and a second solenoid valve is provided on the second branch.

[0010] Preferably, a gas-liquid separator is provided on the top of the liquid storage tank, an exhaust pipe is provided on the gas-liquid separator, the exhaust pipe is used to introduce the gaseous refrigerant in the liquid storage tank into the compression tank, and a second one-way valve is provided on the exhaust pipe.

[0011] Preferably, the liquid storage tank is also provided with a second reflux pipe connected to the second branch, the second reflux pipe extends to the top of the condenser, and the second reflux pipe is connected to the first delivery pipe, the second reflux pipe is provided with a third solenoid valve and a third one-way valve, the condenser is provided with a pressure sensor for monitoring the pressure in the condenser, the second branch is also provided with a third branch for introducing liquid refrigerant into the cooling pipe, and the third branch is provided with a fourth solenoid valve.

[0012] Preferably, a first fan for dissipating heat from the condenser is provided on the external circulation cabinet, a heat dissipation port for cooling the condenser is provided on the top of the external circulation cabinet, and a vent for dissipating heat from the compressor is provided on the bottom of the external circulation cabinet.

[0013] Preferably, an axial flow fan for blowing air to the evaporator is provided on the internal circulation cabinet, and an air inlet and an air outlet are respectively provided on the top and the bottom of the internal circulation cabinet.

[0014] A method for secondary utilization of low-temperature refrigerant is applied to the above-mentioned high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant, comprising the following steps:

[0015] S1: Start the compressor, which compresses the low-temperature and low-pressure gaseous refrigerant into high-temperature and high-pressure gas, and guides the compressed gaseous refrigerant to the condenser through the first delivery pipe. In the condenser, the high-temperature and high-pressure gaseous refrigerant is converted into liquid refrigerant through the heat dissipation process;

[0016] S2: Liquid refrigerant flows from the bottom of the condenser to the expansion throttle valve, which depressurizes and cools the liquid refrigerant to reduce its temperature and pressure, and then delivers the cooled liquid refrigerant to the evaporator;

[0017] S3: The depressurized liquid refrigerant enters the evaporator through the fourth delivery pipe. The evaporator further vaporizes the liquid refrigerant and absorbs the heat of the surrounding air in the process, thereby effectively reducing the air temperature. The liquid refrigerant that is not completely vaporized in the evaporator flows back to the liquid storage tank through the first return pipe. The liquid storage tank stores the liquid refrigerant and prepares for the next stage of circulation.

[0018] S4: The liquid refrigerant in the liquid storage tank is guided into the cooling pipe. The low-temperature refrigerant in the cooling pipe exchanges heat with the liquid refrigerant flowing out of the bottom of the condenser, thereby reducing the temperature of the refrigerant at the bottom of the condenser, allowing the condenser to maintain good heat dissipation performance and reducing the workload of the compressor.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention sets a liquid storage tank between the expansion throttle valve and the evaporator, and combines the first return pipe setting on the evaporator to recycle the unvaporized liquid refrigerant in the evaporator to the liquid storage tank, effectively preventing the liquid refrigerant from entering the compressor, thereby reducing the risk of liquid hammer, protecting the compressor from damage, and improving the safety and efficiency of system operation. The low-temperature refrigerant stored in the liquid storage tank exchanges heat with the medium-temperature and high-pressure liquid refrigerant at the bottom of the condenser through the cooling pipe to form a refrigerant circulation loop. This method reduces the refrigerant temperature at the bottom of the condenser while reducing the heat dissipation burden of the condenser, so that the condenser can maintain good heat dissipation performance in a high-temperature environment, thereby reducing the workload of the compressor and further improving the overall energy efficiency of the air-conditioning system;

[0021] 2. The present invention arranges the second delivery pipe at the bottom of the condenser in a U-shaped structure, and heat is exchanged between the cooling pipe and the liquid refrigerant in the second delivery pipe by winding the cooling pipe around the second delivery pipe. Since the cooling pipe fits tightly with the second delivery pipe and is arranged in a spiral shape, a larger heat exchange area can be achieved in a limited space, which is beneficial to the miniaturization and cost control of the air-conditioning unit. At the same time, the temperature difference between the refrigerants can be fully utilized for efficient heat exchange, thereby reducing the temperature of the medium-temperature and high-pressure liquid refrigerant in the second delivery pipe, thereby reducing the heat dissipation burden of the condenser and improving the heat dissipation efficiency of the condenser. At the same time, it can reduce the working pressure and power consumption of the compressor, extend the service life of the compressor, and make the entire air-conditioning system more energy-efficient and efficient.

[0022] 3. The present invention realizes flexible diversion of the refrigerant output by the expansion throttle valve through the setting of the distribution valve. Through the setting of the capillary tube, the throttling effect of the capillary tube is utilized to keep the refrigerant at a low and stable temperature in the process of flowing through the cooling pipe and returning to the liquid storage tank, thereby reducing the impact of temperature fluctuations on the refrigerant in the liquid storage tank. The stability of the refrigerant temperature in the liquid storage tank directly affects the operating efficiency of the entire air-conditioning system. Lowering the temperature of the refrigerant and alleviating temperature fluctuations in the liquid storage tank through the capillary tube helps the system maintain a stable working state under different load and environmental conditions, thereby improving the overall stability and reliability of the air-conditioning unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a three-dimensional structural diagram of a high-efficiency heat exchange air conditioning unit based on the secondary use of low-temperature refrigerant. Figure 1 ;

[0024] Figure 2 This is a three-dimensional structural diagram of a high-efficiency heat exchange air conditioning unit based on the secondary use of low-temperature refrigerant. Figure 2 ;

[0025] Figure 3 This is a cross-sectional diagram of a high-efficiency heat exchange air conditioning unit based on the secondary use of low-temperature refrigerant. Figure 1 ;

[0026] Figure 4 This is a cross-sectional diagram of a high-efficiency heat exchange air conditioning unit based on the secondary use of low-temperature refrigerant. Figure 2 ;

[0027] Figure 5 This is a three-dimensional structural diagram of the external circulation cabinet and the internal circulation cabinet in a high-efficiency heat exchange air-conditioning unit based on the secondary use of low-temperature refrigerant. Figure 1 ;

[0028] Figure 6 This is a three-dimensional structural diagram of the external circulation cabinet and the internal circulation cabinet in a high-efficiency heat exchange air-conditioning unit based on the secondary use of low-temperature refrigerant. Figure 2 ;

[0029] Figure 7 yes Figure 4 The enlarged view of point A in the middle;

[0030] Figure 8 It is a three-dimensional structural schematic diagram of a liquid storage tank, a second delivery pipe and a cooling pipe in a high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant;

[0031] Fig. 9 It is a three-dimensional structural schematic diagram of a liquid storage tank, a capillary tube and a fourth delivery pipe in a high-efficiency heat exchange air-conditioning unit based on secondary utilization of low-temperature refrigerant;

[0032] Fig.10 The present invention is a three-dimensional structural schematic diagram of a fourth delivery pipe and a first return pipe in a high-efficiency heat exchange air-conditioning unit based on secondary utilization of low-temperature refrigerant.

[0033] The numbers in the figure are: 1, external circulation cabinet; 11, compressor; 12, condenser; 121, first delivery pipe; 122, second delivery pipe; 13, first fan; 14, heat dissipation port; 15, vent; 2, internal circulation cabinet; 21, evaporator; 211, third delivery pipe; 212, fourth delivery pipe; 213, first return pipe; 22, expansion throttle valve; 221, distribution valve; 222, first branch; 223, first solenoid valve; 224, capillary; 225, first non-return valve; 23, liquid storage tank; 231 , cooling pipe; 232, annular cylinder; 2321, liquid storage chamber; 2322, liquid discharge chamber; 2323, liquid delivery pump; 23231, second solenoid valve; 23232, second branch; 233, gas-liquid separator; 2331, exhaust pipe; 2332, second one-way valve; 234, second return pipe; 2341, third one-way valve; 2342, pressure sensor; 235, third branch; 2351, third solenoid valve; 2352, fourth solenoid valve; 24, air inlet; 25, air outlet; 26, axial flow fan. DETAILED DESCRIPTION

[0034] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0035] like Figures 1 to 6 As shown: A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant, including an external circulation cabinet 1 and an internal circulation cabinet 2, wherein a compressor 11 and a condenser 12 are arranged in the external circulation cabinet 1, and an evaporator 21 is arranged in the internal circulation cabinet 2, and an expansion throttle valve 22 is arranged between the condenser 12 and the evaporator 21, and the condenser 12 has a first delivery pipe 121 connected to the compressor 11, and a second delivery pipe 122 connected to the expansion throttle valve 22; the evaporator 21 is connected to the compressor 11 through a third delivery pipe 211, and the evaporator 21 is connected to the expansion throttle valve 22 through a fourth delivery pipe 212; the evaporator 21 is connected to the compressor 11 through a third delivery pipe 211, and the evaporator 21 is connected to the expansion throttle valve 22 through a fourth delivery pipe 212; A liquid storage tank 23 connected to the fourth delivery pipe 212 is arranged between the evaporator 21 and the expansion throttle valve 22, and the liquid storage tank 23 is used to store low-temperature and low-pressure liquid refrigerant; a first reflux pipe 213 is arranged on the evaporator 21 for conveying the unvaporized liquid refrigerant in the evaporator 21 to the liquid storage tank 23; a cooling pipe 231 is wound around the outside of the second delivery pipe 122, one end of the cooling pipe 231 is connected to the liquid storage tank 23, and the other end of the cooling pipe 231 is connected to the fourth delivery pipe 212, so that the low-temperature refrigerant in the liquid storage tank 23 forms a circulation loop through the cooling pipe 231, thereby reducing the temperature of the liquid refrigerant at the bottom of the condenser 12.

[0036] By setting a liquid storage tank 23 between the expansion throttle valve 22 and the evaporator 21, and combining it with the first return pipe 213 connected to the evaporator 21, the unvaporized liquid refrigerant in the evaporator 21 can be recovered to the liquid storage tank 23, effectively preventing the liquid refrigerant from entering the compressor 11, thereby reducing the risk of liquid hammer, protecting the compressor 11 from damage, and improving the safety and efficiency of the system operation.

[0037] The low-temperature refrigerant stored in the liquid storage tank 23 exchanges heat with the medium-temperature and high-pressure liquid refrigerant at the bottom of the condenser 12 through the cooling pipe 231 to form a refrigerant circulation loop. This arrangement reduces the temperature of the refrigerant at the bottom of the condenser 12 while reducing the heat dissipation burden of the condenser 12, so that the condenser 12 can maintain good heat dissipation performance in a high-temperature environment, thereby reducing the workload of the compressor 11 and further improving the overall energy efficiency of the air-conditioning system.

[0038] Normally, the temperature of the liquid refrigerant flowing out of the expansion throttle valve 22 and the evaporator 21 is relatively low, about 10°C, while the temperature of the liquid refrigerant at the bottom of the condenser 12 is generally about 35°C after passing through the heat sink of the condenser 12. By setting the cooling pipe 231, the low-temperature and low-pressure refrigerant in the liquid storage tank 23 and the high-pressure liquid refrigerant flowing out of the bottom of the condenser 12 can exchange heat within an optimal temperature difference range (about 25°C), thereby improving the heat exchange efficiency and reducing the heat dissipation burden of the condenser 12.

[0039] It should be noted that in the heat exchange process, temperature difference is the main driving force of heat exchange, and too large or too small temperature difference will affect the heat exchange efficiency. Generally speaking, a temperature difference of about 25°C is considered to be a more suitable range in refrigerant heat exchange applications. If the low-temperature liquid refrigerant in the liquid storage tank 23 is directly heat exchanged with the high-temperature gaseous refrigerant (about 70°C) at the top of the condenser 12, although the temperature difference between the refrigerant in the cooling pipe 231 and the refrigerant in the condenser 12 is large, the excessive temperature difference may cause uneven temperature distribution on the heat transfer surface, causing the refrigerant temperature in the condenser 12 to fluctuate rapidly, thereby affecting the condensation effect of the condenser 12 and the stability of the overall system operation. The present invention uses the liquid storage tank 23 and the cooling pipe 231 to form a refrigerant circulation loop, so that the refrigerant can pass to the condenser 12 in a suitable heat exchange temperature range, making the refrigerant circulation more efficient and improving the overall refrigeration effect of the system.

[0040] Recycling and reusing the refrigerant through the liquid storage tank 23 not only effectively utilizes the ungasified liquid refrigerant, but also reduces the waste of refrigerant, further reflecting the environmental protection and high efficiency of the system. The liquid refrigerant in the liquid storage tank 23 participates in the heat exchange cycle according to actual needs, especially in a high temperature environment, effectively improving the cooling capacity of the condenser 12, ensuring the efficient operation of the system under extreme conditions, and further optimizing the refrigeration performance.

[0041] It should be noted that the external circulation cabinet 1 and the internal circulation cabinet 2 in the present invention are respectively arranged outdoors and indoors. The external circulation cabinet 1 mainly includes a compressor 11 and a condenser 12, and its main function is to complete the compression and condensation process of the refrigerant, because the condenser 12 needs to dissipate heat through the outdoor air. The internal circulation cabinet 2 includes an evaporator 21, which is responsible for absorbing heat by evaporating the refrigerant to achieve a cooling effect on the indoor air. Since the evaporator 21 needs to exchange heat with the indoor air, the internal circulation cabinet 2 is arranged indoors, which is convenient for directly regulating the temperature of the indoor environment. By separating the inside and the outside, not only can the condenser 12 dissipate heat efficiently, but also avoid the heat loss that may be caused by the direct contact between the evaporator 21 and the outdoor environment, thereby improving the cooling efficiency and operation stability of the entire air-conditioning system.

[0042] like Figures 3 to 6 and Figure 8As shown, the second delivery pipe 122 is disposed at the bottom of the condenser 12 , and the second delivery pipe 122 is a U-shaped structure, and the cooling pipe 231 is spirally wound around the second delivery pipe 122 .

[0043] In the present invention, the second delivery pipe 122 is arranged at the bottom of the condenser 12 in a U-shaped structure, and is used to deliver the liquefied medium-temperature and high-pressure refrigerant in the condenser 12 to the expansion throttle valve 22. Under the action of the cooling pipe 231, the low-temperature and low-pressure liquid refrigerant in the liquid storage tank 23 is introduced into the cooling pipe 231, and heat exchange is performed with the liquid refrigerant in the second delivery pipe 122 through the cooling pipe 231 wound on the second delivery pipe 122. Since the cooling pipe 231 is closely fitted with the second delivery pipe 122 and is arranged in a spiral shape, a larger heat exchange area can be achieved in a limited space, which is conducive to the miniaturization and cost control of the air-conditioning unit, and at the same time, the temperature difference between the refrigerants can be fully utilized for efficient heat exchange, thereby reducing the temperature of the medium-temperature and high-pressure liquid refrigerant in the second delivery pipe 122, thereby reducing the heat dissipation burden of the condenser 12, improving the heat dissipation efficiency of the condenser 12, and at the same time, it can reduce the working pressure and power consumption of the compressor 11, extend the service life of the compressor 11, and make the entire air-conditioning system more energy-saving and efficient.

[0044] It should be noted that, in addition to the above-mentioned arrangement, the second delivery pipe 122 can also be arranged inside the condenser 12, and heat exchange can be achieved at the bottom of the condenser 12 by winding the cooling pipe 231 around the outside of the second delivery pipe 122, or by winding the cooling pipe 231 around the heat sink of the condenser 12 (the second delivery pipe 122 is on the heat sink). However, compared with winding the cooling pipe 231 around the second delivery pipe 122, this method has a lower heat exchange efficiency due to the limited space inside the condenser 12 and the addition of a heat sink as an intermediate medium. However, it can still reduce the heat dissipation burden of the condenser 12 and reduce the working pressure and power consumption of the compressor 11.

[0045] like Figures 3 to 6 , Figures 8 to 10 As shown: a distribution valve 221 for distributing liquid refrigerant and connected to the expansion throttle valve 22 is also provided on the side of the expansion throttle valve 22, and a first branch 222 is provided on the fourth delivery pipe 212. The first branch 222 is used to pass the liquid refrigerant to the liquid storage tank 23, and a first solenoid valve 223 is provided on the first branch 222.

[0046] A distribution valve 221 is set beside the expansion throttle valve 22 to receive the low-temperature and low-pressure liquid refrigerant flowing out of the expansion throttle valve 22 and distribute it to two directions. A part of the refrigerant flows to the evaporator 21 through the fourth delivery pipe 212 to complete the refrigeration cycle; the other part of the refrigerant flows into the liquid storage tank 23 through the first branch 222. The first solenoid valve 223 on the first branch 222 is used to control whether the refrigerant enters the liquid storage tank 23, and automatically adjusts the opening and closing state according to the operation requirements of the system. It can accurately control the flow direction and flow rate of the refrigerant, avoid the refrigerant from entering the liquid storage tank 23 under inappropriate conditions, reduce the risk of liquid hammer, and extend the service life of the compressor 11. In a high temperature environment, by controlling the opening and closing state of the first solenoid valve 223, the excess refrigerant is transported to the liquid storage tank 23 for storage, avoiding excessive refrigerant from entering the evaporator 21 or the compressor 11, reducing the system operation load, and improving the stability and refrigeration performance of the system. Through the setting of the distribution valve 221, the flexible diversion of the refrigerant output by the expansion throttle valve 22 is realized. According to the refrigeration cycle requirements, the ratio of the refrigerant flowing to the evaporator 21 and the liquid storage tank 23 is dynamically adjusted to improve the utilization efficiency of the refrigerant and avoid waste. The recycling of the low-temperature refrigerant in the liquid storage tank 23 helps to reduce the refrigerant temperature at the bottom of the condenser 12 through the cooling pipe 231, reduce the heat dissipation burden of the condenser 12, and thus improve its operating efficiency. The distribution valve 221 works in conjunction with the liquid storage tank 23 to provide support for the continuous and stable operation of the condenser 12. The combination of the distribution valve 221 and the first solenoid valve 223 realizes the dynamic adjustment of the refrigerant flow direction, making the entire air-conditioning system more diversified in function and occupying less space, which is conducive to the miniaturization and cost control of the unit.

[0047] like Figures 4 to 6 , Figures 8 to 10 As shown: a capillary tube 224 capable of cooling the refrigerant is provided between the cooling tube 231 and the distribution valve 221 , the capillary tube 224 is in a spiral structure, one end of the capillary tube 224 is connected to the distribution valve 221 , and the other end of the capillary tube 224 is connected to the cooling tube 231 .

[0048] When the cooling tube 231 performs heat exchange with the liquid refrigerant flowing out of the condenser 12, it absorbs the heat of the refrigerant at the bottom of the condenser 12, thereby increasing the temperature of the refrigerant in the cooling tube 231. After the refrigerant in the cooling tube 231 flows through the second delivery pipe 122, the refrigerant will continue to flow and enter the capillary tube 224. The capillary tube 224 reduces the pressure of the liquid refrigerant through throttling, causing its temperature to further drop. The spiral structure of the capillary tube 224 helps to increase the contact area between the refrigerant and the inner wall of the capillary tube 224, improve the cooling efficiency of the refrigerant, and thus improve the heat exchange performance of the entire air conditioning system.

[0049] Keeping the refrigerant temperature of the condenser 12 within the ideal range helps reduce the workload of the compressor 11 and the condenser 12, prevents the system from overheating, and prolongs the service life of the equipment. At the same time, this setting reduces the demand for additional energy and improves the energy saving effect of the air conditioning system. The capillary tube 224 has a compact spiral structure, which can effectively utilize space and improve the cooling efficiency in a limited space.

[0050] The throttling effect of the capillary tube 224 allows the refrigerant to maintain a relatively low and stable temperature during the process of being introduced into the liquid storage tank 23 again through the distribution valve 221 after flowing through the cooling pipe 231, thereby reducing the impact of temperature fluctuations on the refrigerant in the liquid storage tank 23. The stability of the refrigerant temperature in the liquid storage tank 23 directly affects the operating efficiency of the entire air conditioning system. Lowering the temperature of the refrigerant and alleviating temperature fluctuations in the liquid storage tank 23 by the capillary tube 224 helps the system maintain a stable working state under different load and environmental conditions, thereby improving the overall stability and reliability of the air conditioning unit.

[0051] like Figures 4 to 10 As shown: an annular cylinder 232 with an opening on the top is provided in the liquid storage tank 23, the annular cylinder 232 divides the interior of the liquid storage tank 23 into a liquid storage chamber 2321 and a liquid discharge chamber 2322, the first reflux pipe 213 extends to the bottom of the liquid storage tank 23 and is connected with the interior of the liquid storage chamber 2321, and a first one-way valve 225 is provided on the first reflux pipe 213 of the evaporator 21; a liquid delivery pump 2323 is provided on the liquid discharge chamber 2322, and a second branch 23232 is also provided on the liquid delivery pump 2323, the second branch 23232 is used to lead the refrigerant from the liquid discharge chamber 2322 to the fourth delivery pipe 212, and a second solenoid valve 23231 is provided on the second branch 23232.

[0052] The liquid storage tank 23 can be divided into a liquid storage chamber 2321 and a liquid discharge chamber 2322 by the annular cylinder 232. The liquid storage chamber 2321 is used to collect liquid refrigerant. When the liquid refrigerant in the liquid storage chamber 2321 is full, it will overflow from the top of the liquid storage chamber 2321 and flow into the liquid discharge chamber 2322. Such a setting is to ensure the first-in-first-out (FIFO) flow of the refrigerant in the liquid storage tank 23 to avoid unstable operation caused by insufficient refrigerant or temperature fluctuations. Sufficient liquid refrigerant is always maintained in the liquid storage chamber 2321, which helps to maintain a stable temperature in the liquid storage tank 23 and ensure the efficient operation of the system. Through the setting of the first return pipe 213 and the first one-way valve 225, the refrigerant refluxed from the evaporator 21 can only flow into the liquid storage chamber 2321, and the setting of entering from the bottom of the liquid storage chamber 2321 can ensure that the refrigerant will not splash into the liquid discharge chamber 2322 when it is introduced.

[0053] The liquid delivery pump 2323 is provided on the liquid discharge chamber 2322, and the refrigerant is delivered to the fourth delivery pipe 212 through the second branch 23232 as needed. Then, by cooperating with the distribution valve 221, the liquid refrigerant can be accurately delivered to the evaporator 21. Through the setting of the second solenoid valve 23231, the flow direction of the refrigerant can be accurately controlled to ensure that the liquid refrigerant enters the fourth delivery pipe 212 from the liquid discharge chamber 2322, thereby realizing accurate regulation of the refrigerant flow.

[0054] like Figures 4 to 10 As shown: a gas-liquid separator 233 is arranged on the top of the liquid storage tank 23, and an exhaust pipe 2331 is arranged on the gas-liquid separator 233. The exhaust pipe 2331 is used to introduce the gaseous refrigerant in the liquid storage tank 23 into the compressor 11, and a second one-way valve 2332 is arranged on the exhaust pipe 2331.

[0055] When the air conditioning system is shut down, the refrigerant stored in the liquid storage tank 23 will change phase with the change of ambient temperature, and may be transformed from liquid refrigerant to gaseous refrigerant, and in the process of refrigerant recovery, part of the gaseous refrigerant may also be mixed into the liquid storage tank 23. In order to solve this problem, a gas-liquid separator 233 is set at the top of the liquid storage tank 23, and the function of the gas-liquid separator 233 is to effectively separate the liquid refrigerant from the gaseous refrigerant. Due to the effect of gravity, the liquid refrigerant will settle to the bottom of the liquid storage tank 23, while the gaseous refrigerant will rise and be collected by the gas-liquid separator 233. When enough gaseous refrigerant accumulates in the gas-liquid separator 233, the gaseous refrigerant will be discharged through the exhaust pipe 2331, and the exhaust pipe 2331 is provided with a second one-way valve 2332 to ensure that the gaseous refrigerant can only flow to the compressor 11 in one direction. The setting of the second one-way valve 2332 prevents the gaseous refrigerant from flowing back to the liquid storage tank 23, thereby ensuring the flow direction and discharge efficiency of the refrigerant. The effective separation function of the gas-liquid separator 233 can prevent liquid refrigerant from entering the compressor 11. The gas-liquid separator 233 can ensure that an appropriate amount of liquid refrigerant is always maintained in the liquid storage tank 23, thereby ensuring stable operation of the system, improving refrigeration efficiency, and avoiding liquid hammer. The separation effect of the gas-liquid separator 233 reduces unnecessary interference in the refrigerant flow, ensuring efficient and stable operation of the system, and optimizing the performance of the overall air-conditioning unit.

[0056] like Figures 4 to 10As shown: the liquid storage tank 23 is also provided with a second return pipe 234 connected with the second branch 23232, the second return pipe 234 extends to the top of the condenser 12, and the second return pipe 234 is connected with the first delivery pipe 121, the second return pipe 234 is provided with a third solenoid valve 2351 and a third one-way valve 2341, the condenser 12 is provided with a pressure sensor 2342 for monitoring the pressure in the condenser 12, the second branch 23232 is also provided with a third branch 235 for introducing liquid refrigerant into the cooling pipe 231, and the third branch 235 is provided with a fourth solenoid valve 2352.

[0057] After the air conditioning system is shut down, the refrigerant stored in the liquid storage tank 23 will change with the ambient temperature, especially in hot weather, the temperature of the refrigerant in the discharge chamber 2322 of the liquid storage tank 23 becomes higher. When the system is restarted, if this part of the refrigerant is led to the evaporator 21 through the second branch 23232 and the fourth delivery pipe 212, it will affect the use of the evaporator 21. Through the setting of the second return pipe 234, the heated refrigerant in the liquid storage tank 23 can be introduced into the top of the condenser 12. At this time, the refrigerant at the top of the condenser 12 is not heated because the air conditioning system is shut down. The refrigerant in the liquid storage tank 23 will also be close to the ambient temperature. Therefore, the refrigerant in the liquid storage tank 23 and the condenser 12 can be combined through the introduction of the second return pipe 234, so that the refrigerant in the liquid storage tank 23 can circulate with the pipeline of the condenser 12, ensuring that the refrigerant in the liquid storage tank 23 can quickly enter the circulation of the air-conditioning system when the air-conditioner is turned on again after a long period of non-use, avoiding the refrigerant in the liquid storage tank 23 from affecting the evaporator 21 due to the high temperature during use, and can reduce the running time of the air-conditioner when it is turned on, so that the air-conditioner can quickly cool down the room.

[0058] The third one-way valve 2341 on the second return pipe 234 ensures that the refrigerant can only flow in one direction to prevent unnecessary backflow. The third solenoid valve 2351 is set to accurately control the flow direction of the refrigerant. The pressure sensor 2342 monitors the refrigerant pressure changes in the condenser 12 in real time to ensure that the refrigerant in the liquid storage tank 23 is only introduced into the condenser 12 when the pressure of the condenser 12 is weakened (the refrigerant pressure in the condenser 12 will drop in the absence of the compressor 11 when it is not used for a long time), so as to avoid the liquid refrigerant in the liquid storage tank 23 that has not been heated too high to be introduced into the top of the condenser 12 after the air conditioner is shut down for a short time.

[0059] Through the combination of the third branch 235 and the liquid delivery pump 2323, the refrigerant can be delivered to the cooling pipe 231 according to demand, and the flow rate and flow direction of the refrigerant are controlled by the fourth solenoid valve 2352, and the supply of the refrigerant is accurately adjusted, so as to more accurately control the heat dissipation temperature of the condenser 12. Since the influence of the ambient temperature on the refrigerant in the liquid storage tank 23 is avoided, the burden on various components in the system can be effectively reduced, and the service life of the air conditioning system can be extended.

[0060] like Figures 1 to 4 As shown: a first fan 13 for dissipating heat from a condenser 12 is provided on the external circulation cabinet 1, a heat dissipation port 14 for cooling the condenser 12 is provided on the top of the external circulation cabinet 1, and a vent 15 for dissipating heat from a compressor 11 is provided on the bottom of the external circulation cabinet 1.

[0061] The first fan 13 provided on the external circulation cabinet 1 can effectively increase the air flow around the condenser 12, accelerate the heat dissipation of the condenser 12, and improve the heat exchange efficiency of the condenser 12, which can maintain the normal operating temperature of the condenser 12 under high load operation and avoid the reduction of efficiency or overheating of the equipment due to poor heat dissipation. The vents 15 provided at the bottom of the external circulation cabinet 1 can provide sufficient air flow for the compressor 11, effectively reduce the heat generated by the compressor 11 when it is working, and ensure its stable operation. This helps to extend the service life of the compressor 11 and prevent failures caused by overheating.

[0062] By optimizing the heat dissipation effect of the condenser 12 and the compressor 11, the air conditioning system can operate more efficiently at higher ambient temperatures. The heat dissipation capacity of the system is improved, which helps to reduce overall energy consumption, improve refrigeration efficiency, and achieve energy saving. The effective heat dissipation of the condenser 12 and the compressor 11 not only improves operating efficiency, but also effectively prevents equipment failures caused by overheating, and improves the reliability and stability of the system. It helps the air conditioner maintain stable performance during long-term operation or high-temperature environments.

[0063] like Figures 1 to 4 As shown, an axial flow fan 26 for blowing air to the evaporator 21 is arranged on the internal circulation cabinet 2, and an air inlet 24 and an air outlet 25 are respectively arranged on the top and the bottom of the internal circulation cabinet 2.

[0064] By equipping the internal circulation cabinet 2 with an axial flow fan 26, indoor air is sucked in through the air inlet 24. The air is pushed by the axial flow fan 26 and guided to the surface of the evaporator 21. On the evaporator 21, the air exchanges heat with the low-temperature refrigerant, the air is cooled and absorbs the cold in the evaporator 21, and then the cooled air is discharged through the air outlet 25 and enters the room, achieving a cooling effect. It ensures that the air can effectively contact the evaporator 21, improves the heat exchange efficiency of the evaporator 21, and thus improves the cooling effect of the entire air conditioning unit.

[0065] Through the action of the axial flow fan 26, the air conditioning unit can blow cold air out of the evaporator 21 more efficiently, increase the delivery volume of cold air, and thus improve the refrigeration performance of the entire air conditioning system. Reasonable arrangement of the fan and optimization of the air circulation path ensure that the indoor air circulates continuously, thereby reducing the load fluctuation of the air conditioning unit and improving the stability and long-term operation efficiency of the system.

[0066] like Figures 1 to 6 and Figure 8 As shown: A method for secondary utilization of low-temperature refrigerant is applied to the above-mentioned high-efficiency heat exchange air-conditioning unit based on secondary utilization of low-temperature refrigerant, comprising the following steps:

[0067] S1: Start the compressor 11, which compresses the low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gas, and guides the compressed gaseous refrigerant to the condenser 12 through the first delivery pipe 121. In the condenser 12, the high-temperature and high-pressure gaseous refrigerant is converted into liquid refrigerant through a heat dissipation process;

[0068] S2: The liquid refrigerant flows from the bottom of the condenser 12 to the expansion throttle valve 22. The expansion throttle valve 22 depressurizes and cools the liquid refrigerant to reduce its temperature and pressure, and transports the cooled liquid refrigerant to the evaporator 21.

[0069] S3: The depressurized liquid refrigerant enters the evaporator 21 through the fourth delivery pipe 212. The evaporator 21 further vaporizes the liquid refrigerant and absorbs the heat of the surrounding air in the process, thereby effectively reducing the air temperature. The liquid refrigerant that is not completely vaporized in the evaporator 21 flows back to the liquid storage tank 23 through the first return pipe 213. The liquid storage tank 23 stores the liquid refrigerant and prepares for the next stage of circulation.

[0070] S4: The liquid refrigerant in the liquid storage tank 23 is guided into the cooling pipe 231. The low-temperature refrigerant in the cooling pipe 231 exchanges heat with the liquid refrigerant flowing out of the bottom of the condenser 12, thereby reducing the temperature of the refrigerant at the bottom of the condenser 12, so that the condenser 12 maintains good heat dissipation performance and reduces the workload of the compressor 11.

[0071] The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the protection scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant, comprising an external circulation cabinet (1) and an internal circulation cabinet (2), wherein a compressor (11) and a condenser (12) are arranged in the external circulation cabinet (1), an evaporator (21) is arranged in the internal circulation cabinet (2), an expansion throttle valve (22) is arranged between the condenser (12) and the evaporator (21), the condenser (12) has a first delivery pipe (121) connected to the compressor (11) and a second delivery pipe (122) connected to the expansion throttle valve (22); the evaporator (21) and the compressor (11) are connected via a third delivery pipe (211), and the evaporator (21) is connected to the expansion throttle valve (22) via a fourth delivery pipe (212); characterized in that: A liquid storage tank (23) connected to a fourth delivery pipe (212) is provided between the evaporator (21) and the expansion throttle valve (22); a first branch (222) is provided on the fourth delivery pipe (212); the first branch (222) is used to pass liquid refrigerant to the liquid storage tank (23); the liquid storage tank (23) is used to store low-temperature and low-pressure liquid refrigerant; a first return pipe (213) is provided on the evaporator (21) for passing unvaporized liquid refrigerant in the evaporator (21) to the liquid storage tank (23); a second delivery pipe (122) is wound around the outside A cooling pipe (231), one end of which is connected to the liquid storage tank (23), and the other end of which is connected to the fourth delivery pipe (212), so that the low-temperature refrigerant in the liquid storage tank (23) forms a circulation loop through the cooling pipe (231), thereby reducing the temperature of the liquid refrigerant at the bottom of the condenser (12); the second delivery pipe (122) is arranged at the bottom of the condenser (12), and the second delivery pipe (122) is a U-shaped structure, and the cooling pipe (231) is spirally wound around the second delivery pipe (122).

2. According to claim 1, a high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant is characterized in that: A distribution valve (221) for distributing liquid refrigerant and in communication with the expansion throttle valve (22) is also provided on the side of the expansion throttle valve (22), and a first solenoid valve (223) is provided on the first branch (222).

3. A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 2, characterized in that: A capillary tube (224) capable of cooling the refrigerant is provided between the cooling tube (231) and the distribution valve (221); the capillary tube (224) has a spiral structure; one end of the capillary tube (224) is connected to the distribution valve (221); and the other end of the capillary tube (224) is connected to the cooling tube (231).

4. A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 2, characterized in that: An annular cylinder (232) having an opening at the top is arranged in the liquid storage tank (23), and the annular cylinder (232) divides the interior of the liquid storage tank (23) into a liquid storage chamber (2321) and a liquid discharge chamber (2322). The first return pipe (213) extends to the bottom of the liquid storage tank (23) and is in communication with the interior of the liquid storage chamber (2321), and a first one-way valve (225) is arranged on the first return pipe (213) of the evaporator (21); a liquid delivery pump (2323) is arranged on the liquid discharge chamber (2322), and a second branch (23232) is also arranged on the liquid delivery pump (2323), and the second branch (23232) is used to guide the refrigerant from the liquid discharge chamber (2322) to the fourth delivery pipe (212), and a second solenoid valve (23231) is arranged on the second branch (23232).

5. The high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 1, characterized in that: A gas-liquid separator (233) is provided on the top of the liquid storage tank (23); an exhaust pipe (2331) is provided on the gas-liquid separator (233); the exhaust pipe (2331) is used to guide the gaseous refrigerant in the liquid storage tank (23) into the compression tank; and a second one-way valve (2332) is provided on the exhaust pipe (2331).

6. A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 4, characterized in that: The liquid storage tank (23) is also provided with a second return pipe (234) connected to the second branch (23232), the second return pipe (234) extends to the top of the condenser (12), and the second return pipe (234) is connected to the first delivery pipe (121), the second return pipe (234) is provided with a third solenoid valve (2351) and a third one-way valve (2341), the condenser (12) is provided with a pressure sensor (2342) for monitoring the pressure in the condenser (12), the second branch (23232) is also provided with a third branch (235) for introducing liquid refrigerant into the cooling pipe (231), and the third branch (235) is provided with a fourth solenoid valve (2352).

7. A high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 6, characterized in that: The external circulation cabinet (1) is provided with a first fan (13) for dissipating heat from the condenser (12), the top of the external circulation cabinet (1) is provided with a heat dissipation port (14) for cooling the condenser (12), and the bottom of the external circulation cabinet (1) is provided with a vent (15) for dissipating heat from the compressor (11).

8. The high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to claim 7, characterized in that: An axial flow fan (26) for blowing air to the evaporator (21) is provided on the internal circulation cabinet (2), and an air inlet (24) and an air outlet (25) are respectively provided on the top and bottom of the internal circulation cabinet (2).

9. A method for secondary utilization of low-temperature refrigerant, applied to a high-efficiency heat exchange air conditioning unit based on secondary utilization of low-temperature refrigerant according to any one of claims 1 to 8, characterized in that: The following steps are included: S1: starting the compressor (11), the compressor (11) compressing the low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gas, and guiding the compressed gaseous refrigerant to the condenser (12) through the first delivery pipe (121), and in the condenser (12), the high-temperature and high-pressure gaseous refrigerant is converted into a liquid refrigerant through a heat dissipation process; S2: the liquid refrigerant flows from the bottom of the condenser (12) to the expansion throttle valve (22), the expansion throttle valve (22) depressurizes and cools the liquid refrigerant to reduce its temperature and pressure, and transports the cooled liquid refrigerant to the evaporator (21); S3: the depressurized liquid refrigerant enters the evaporator (21) through the fourth delivery pipe (212), the evaporator (21) further vaporizes the liquid refrigerant and absorbs heat from the surrounding air during the process, thereby effectively reducing the air temperature, the liquid refrigerant in the evaporator (21) that is not completely vaporized flows back to the liquid storage tank (23) through the first return pipe (213), the liquid storage tank (23) stores the liquid refrigerant and prepares for the next stage of circulation; S4: The liquid refrigerant in the liquid storage tank (23) is guided into the cooling pipe (231), and the low-temperature refrigerant in the cooling pipe (231) exchanges heat with the liquid refrigerant flowing out from the bottom of the condenser (12), thereby reducing the temperature of the refrigerant at the bottom of the condenser (12), allowing the condenser (12) to maintain good heat dissipation performance and reducing the workload of the compressor (11).

Images