A carbon dioxide heat pump system

Abstract

The present invention provides a carbon dioxide heat pump system, which relates to the technical field of heat pump systems and includes: an evaporator: The evaporator is the cold end of the carbon dioxide heat pump system, which absorbs heat to achieve the cooling of air; a gas-liquid separator: The function of the gas-liquid separator is to separate the gas and liquid in the refrigerant from the evaporator; a compressor: The compressor is the hot end of the carbon dioxide heat pump system. The present invention provides a carbon dioxide heat pump system. By arranging an evaporator, a gas-liquid separator, a compressor, an air cooler, a first fan, a second fan, a throttle and a regenerator, the high-pressure medium-temperature gas converted by the evaporator can be cooled and depressurized before being input into the compressor, reducing the damage caused by the high-pressure medium-temperature refrigerant to the compressor and also reducing the protection mechanism for the compressor to overheat and stop. The entire heat pump system can operate in a cycle. Moreover, the structure of this system is simple, the manufacturing is simple, and the cost is low, so it can be widely promoted and used.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pump systems, and in particular to a carbon dioxide heat pump system. Background Art

[0002] As a fourth-generation refrigerant, carbon dioxide refrigerant has the characteristics of environmental protection, non-toxicity, and non-flammability. Carbon dioxide heat pumps also have the characteristics of high-temperature water output and efficient heating at low ambient temperatures, and have good market prospects. Current carbon dioxide heat pump systems are usually applied in fields such as building heating and cooling, industrial heat pumps, geothermal energy, drying rooms, etc. However, when a carbon dioxide heat pump is applied in a drying room, compressor overheating shutdown is a common protective measure. The reasons for compressor overheating shutdown include excessive refrigerant filling, blockage in the system management, too high ambient temperature or the presence of a heat source, the evaporator or the dust collection structure of the filter screen, problems with the fan or air duct, poor heat dissipation, etc. Most of the main reasons are that the refrigerant temperature is too high, resulting in compressor overheating. Although overheating shutdown is a protective measure for the compressor, the overheating phenomenon may still cause damage to the compressor. For example, the metal components inside the compressor may deform or even be damaged at high temperatures, and the performance of the lubricating oil may decline and the service life may be shortened. Summary of the Invention

[0003] Based on the technical problems existing in the background art, the present invention proposes a carbon dioxide heat pump system.

[0004] A carbon dioxide heat pump system proposed by the present invention includes:

[0005] Evaporator: The evaporator is the cold end of the carbon dioxide heat pump system, which absorbs heat to achieve air cooling.

[0006] Gas-liquid separator: The function of the gas-liquid separator is to separate the gas and liquid in the refrigerant from the evaporator.

[0007] Compressor: The compressor is the hot end of the carbon dioxide heat pump system. It compresses the low-temperature and low-pressure refrigerant from the gas-liquid separator into a high-temperature and high-pressure refrigerant.

[0008] Gas cooler: The gas cooler is the hot end of the carbon dioxide heat pump system, which is used to release the heat of the high-temperature and high-pressure refrigerant compressed by the compressor.

[0009] First fan: The first fan provides air flow for the gas cooler to help the refrigerant release heat.

[0010] Second fan: It is used to accelerate the air flow speed on the surface of the evaporator and improve the heat exchange efficiency.

[0011] Regenerator: The regenerator can conduct heat exchange between the low-temperature and low-pressure liquid refrigerant passing through the gas cooler and the high-pressure and medium-temperature refrigerant passing through the evaporator. The regenerator can convert the high-pressure and medium-temperature refrigerant into a low-pressure and low-temperature refrigerant, and the regenerator can also adjust the pressure inside it to convert the high-pressure and medium-temperature refrigerant into a low-pressure and low-temperature refrigerant;

[0012] Throttle: Used to control the input of the low-temperature and low-pressure liquid refrigerant for heat exchange in the regenerator into the evaporator;

[0013] Wherein the throttle can also control the entry of the low-pressure and low-temperature liquid refrigerant converted by the gas cooler into the evaporator; the gas-liquid separator can also separate the low-pressure and low-temperature refrigerant converted by the regenerator into gas and liquid.

[0014] Preferably, the regenerator includes a heat exchange barrel, a first communication box, a second communication box, heat exchange tubes, a partition board, a low-pressure and low-temperature outlet pipe, a low-pressure and low-temperature inlet pipe, a high-pressure and medium-temperature inlet pipe, and a high-pressure and medium-temperature outlet pipe; a working chamber is provided in the heat exchange barrel, a first communication cavity is provided in the first communication box, a second communication cavity is provided in the second communication box, the first communication box and the second communication box are respectively fixedly installed at both ends of the heat exchange barrel, the number of the heat exchange tubes is multiple, and multiple heat exchange tubes are all located in the working chamber of the heat exchange barrel. The two ends of the heat exchange tube respectively penetrate through both ends of the heat exchange barrel, and the two ends of the heat exchange tube respectively extend into the first communication cavity and the second communication cavity. The partition board is fixedly installed in the second communication cavity, and the partition board can divide the second working chamber into two independent first chambers and second chambers. The partition board also divides the ends of multiple heat exchange tubes into the first chamber and the second chamber. The intake end of the low-pressure and low-temperature outlet pipe communicates with the first chamber, and the outlet end of the low-pressure and low-temperature outlet pipe communicates with the throttle;

[0015] The outlet end of the low-pressure and low-temperature inlet pipe communicates with the second chamber, and the intake end of the low-pressure and low-temperature inlet pipe communicates with the gas cooler;

[0016] A pressure control structure is slidably installed in the working chamber of the heat exchange barrel. The pressure control structure can divide the working chamber into two independent variable chambers and a pressure control chamber, and the pressure control structure can control the space size of the pressure control chamber;

[0017] The high-pressure and medium-temperature inlet pipe and the high-pressure and medium-temperature outlet pipe both communicate with the pressure control chamber. The high-pressure and medium-temperature inlet pipe also communicates with the evaporator, and the high-pressure and medium-temperature outlet pipe communicates with the gas-liquid separator.

[0018] Preferably, the pressure control structure includes a pressure control plate and an electric push rod; the pressure control plate is slidably installed in the working chamber of the heat exchange barrel, and a plurality of the heat exchange tubes all penetrate through the pressure control plate. The plurality of heat exchange tubes are arranged in parallel. The electric push rod is fixedly installed on the first communication box. The output shaft of the electric push rod slidably penetrates through the first communication box, the end of the heat exchange barrel and extends into the working chamber to be fixedly connected with the pressure control plate.

[0019] Preferably, a telescopic tube is installed through the pressure control plate. The telescopic tube is slidably inserted into the high-pressure medium-temperature inlet pipe, and the outer diameter of the telescopic tube is the same as the inner diameter of the high-pressure medium-temperature inlet pipe.

[0020] Preferably, the evaporator and the regenerator are connected through a first pipe, and a first one-way valve is installed on the first pipe. The regenerator and the gas-liquid separator are connected through a second pipe.

[0021] Preferably, the evaporator and the gas-liquid separator are connected through a third pipe, and a second one-way valve is installed on the third pipe.

[0022] Preferably, the air cooler and the regenerator are connected through a fourth pipe, and a third one-way valve is installed on the fourth pipe.

[0023] Preferably, the air cooler and the throttle are connected through a fifth pipe, and a fourth one-way valve is installed on the fifth pipe.

[0024] A carbon dioxide heat pump system proposed by the present invention has the following beneficial effects: by arranging an evaporator, a gas-liquid separator, a compressor, an air cooler, a first fan, a second fan, a throttle and a regenerator, the high-pressure medium-temperature gas converted by the evaporator can be cooled and depressurized and then input into the compressor, reducing the damage to the compressor caused by the high-pressure medium-temperature refrigerant, and also reducing the protection mechanism of the compressor from overheating and shutting down. The entire heat pump system can operate in a cycle, and the structure of this system is simple, the manufacturing is simple, and the cost is low, so it can be widely promoted and used. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of a carbon dioxide heat pump system proposed by the present invention;

[0026] Figure 2 is a side sectional view of the regenerator in a carbon dioxide heat pump system proposed by the present invention;

[0027] Figure 3 is an end sectional view of the second communication box in a carbon dioxide heat pump system proposed by the present invention;

[0028] Figure 4 is an end sectional view of the first communication box in a carbon dioxide heat pump system proposed by the present invention;

[0029] Figure 5 This is a schematic structural diagram of a control pressure plate, a telescopic tube, and a high-pressure medium-temperature inlet pipe in a carbon dioxide heat pump system proposed by the present invention.

[0030] In the figure: 1. Evaporator; 2. Gas-liquid separator; 3. Compressor; 4. Gas cooler; 5. First fan; 6. Second fan; 7. Regenerator; 701. Heat exchange barrel; 702. First communication box; 703. Second communication box; 704. Heat exchange tube; 705. Partition board; 706. Low-pressure low-temperature outlet pipe; 707. Low-pressure low-temperature inlet pipe; 708. High-pressure medium-temperature inlet pipe; 709. High-pressure medium-temperature outlet pipe; 710. Pressure control chamber; 711. Control pressure plate; 712. Electric push rod; 713. Telescopic tube; 8. Throttle; 9. First one-way valve; 10. Second one-way valve; 11. Third one-way valve; 12. Fourth one-way valve. Specific embodiments

[0031] Referring to Figures 1 - 5 , the present invention proposes a carbon dioxide heat pump system, including:

[0032] Evaporator 1: The evaporator 1 is the cold end of the carbon dioxide heat pump system, absorbing heat to achieve air cooling; Second fan 6: Used to accelerate the air flow speed on the surface of the evaporator 1 and improve the heat exchange efficiency; The evaporator 1 converts the low-pressure low-temperature liquid carbon dioxide refrigerant into a high-temperature high-pressure refrigerant. The low-pressure low-temperature liquid carbon dioxide refrigerant is converted by the gas cooler 4, or after being converted by the gas cooler 4 and then undergoing heat exchange in the regenerator 7. The evaporator 1 and the second fan 6 are used in combination. The second fan 6 forces air to flow. When the air flows, the refrigerant in the evaporator 1 absorbs the heat of the air, and the low-temperature low-pressure refrigerant evaporates and becomes gaseous due to heat. As the temperature rises, it also expands and contracts due to thermal expansion and contraction. The low-temperature low-pressure refrigerant is converted into a high-pressure medium-temperature refrigerant. In actual situations, the converted high-pressure medium-temperature refrigerant will enter the compressor 3 directly after being separated by the gas-liquid separator 2. The entry of high-pressure gas into the compressor 3 may cause damage to the compressor 3. For example:

[0033] 1. Mechanical shock: The sudden entry of high-pressure gas into the compressor 3 may generate a high mechanical shock. This shock may damage the internal components of the compressor 3, such as pistons, connecting rods, bearings, and seals.

[0034] 2. Lubrication problem: High-pressure gas may affect the lubrication system of the compressor 3. Due to the impact of high-pressure gas, the flow of lubricating oil in the system may be disturbed, thus affecting the normal lubrication of the compressor 3.

[0035] 3. Seal failure: High-pressure gas may exert excessive pressure on the sealing components of the compressor 3, resulting in seal failure or damage. This may lead to refrigerant leakage, affecting the efficiency and safety of the system.

[0036] 4. Overload of compressor 3: High-pressure gas may cause an increase in the load of the compressor 3, making it unable to operate normally. This may lead to overheating, overload, or other performance problems.

[0037] Similarly, the entry of high-temperature gas into the compressor 3 may also cause damage to the compressor 3, such as:

[0038] 1. Lubrication problems: High-temperature gas may cause the evaporation of the compressor lubricating oil, thereby reducing the amount of lubricating oil and affecting the lubrication effect of the compressor 3, increasing the risk of wear and damage.

[0039] 2. Material degradation: High temperature may accelerate the degradation and aging of the internal materials of the compressor 3, especially rubber, plastic, and sealing materials, etc., resulting in a decline in their performance and even failure.

[0040] 3. Overheating of compressor 3: High-temperature gas generates more heat during the compression process, which may cause the internal temperature of the compressor 3 to be too high, thus affecting the normal operation of the compressor 3 and even possibly causing the overheat protection device of the compressor 3 to start, stopping the compressor 3.

[0041] 4. Reduction in compression efficiency: High-temperature gas may reduce the compression efficiency of the compressor 3 because high temperature causes the viscosity of the refrigerant to decrease, increasing the flow resistance and thus reducing the overall efficiency of the system.

[0042] 5. Seal failure: High temperature may cause the rubber or seals inside the compressor 3 to soften or melt, resulting in seal failure, thereby causing refrigerant leakage and affecting the safety and efficiency of the system.

[0043] Due to the above various reasons, it may cause damage to the compressor 3, or it may also cause the heat pump system to be unable to circulate, resulting in damage to the compressor 3. Therefore, the regenerator 7 is designed. Through the design of the regenerator 7, the high-pressure medium-temperature refrigerant converted by the evaporator 1 is depressurized and cooled, and then the depressurized and cooled refrigerant is separated into gas and liquid and enters the compressor 3 for operation, thereby ensuring the normal operation of the compressor 3 and ensuring the circulation of the entire heat pump system.

[0044] Gas-liquid separator 2: The function of the gas-liquid separator 2 is to separate the gaseous and liquid states in the refrigerant from the evaporator 1; the high-pressure medium-temperature refrigerant converted by the evaporator 1 directly enters the gas-liquid separator 2, or the high-pressure medium-temperature refrigerant converted by the evaporator 1 first enters the regenerator 7 for heat exchange to reduce the temperature and pressure, and then the low-pressure low-temperature refrigerant after pressure and temperature reduction is subjected to gas-liquid separation, which can prevent liquid refrigerant from entering the compressor 3, because the liquid refrigerant will damage the compressor 3 due to liquid hammer in the compressor 3. The specific situation of the liquid hammer phenomenon: 1. Characteristics of liquid refrigerant: The density of liquid refrigerant is much greater than that of gaseous refrigerant and has a relatively high viscosity. When the liquid refrigerant is sucked into the compressor 3, it will quickly turn into a high-temperature and high-pressure gas due to compression; 2. Liquid hammer phenomenon: The liquid refrigerant evaporates rapidly in the compressor 3 due to sudden compression. This process will generate a very high local pressure peak. If this peak pressure is high enough, it may cause damage to the internal components of the compressor 3, such as valve plates, pistons, connecting rods, etc. This phenomenon is called liquid hammer, and it is one of the main reasons for compressor 3 damage.

[0045] Compressor 3: The compressor 3 is the hot end of the carbon dioxide heat pump system. It compresses the low-temperature and low-pressure refrigerant from the gas-liquid separator 2 into a high-temperature and high-pressure refrigerant; the compressor 3 compresses the low-pressure and low-temperature refrigerant separated by the gas-liquid separator 2 into a high-temperature and high-pressure gas.

[0046] Gas cooler 4: The gas cooler 4 is also called a condenser. In this solution, an air-cooled condenser is used. The gas cooler 4 is the hot end of the carbon dioxide heat pump system and is used to release the heat of the high-temperature and high-pressure refrigerant compressed by the compressor 3. First fan 5: The first fan 5 provides air flow for the gas cooler 4 to help the refrigerant release heat; in actual use, through the combined use of the first fan 5 and the gas cooler 4, the first fan 5 drives the air flow, thereby helping the refrigerant release heat and converting the high-temperature and high-pressure refrigerant into a low-temperature and low-pressure liquid refrigerant (by releasing the heat of the refrigerant, the temperature of the refrigerant becomes lower, but since the heat of the refrigerant decreases, the pressure also decreases, based on the principle of thermal expansion and contraction).

[0047] Regenerator 7: The regenerator 7 can perform heat exchange between the low-temperature and low-pressure liquid refrigerant passing through the gas cooler 4 and the high-pressure medium-temperature refrigerant passing through the evaporator 1. The regenerator 7 can convert the high-pressure medium-temperature refrigerant into a low-pressure low-temperature refrigerant; the regenerator 7 can also adjust the pressure inside it so that the high-pressure medium-temperature refrigerant is converted into a low-pressure low-temperature refrigerant. The regenerator 7 can perform heat exchange between the high-pressure medium-temperature refrigerant converted by the evaporator 1 and the low-pressure low-temperature refrigerant converted by the gas cooler 4, so that the heat in the high-pressure medium-temperature refrigerant is taken away by the low-pressure low-temperature refrigerant, thereby reducing the pressure and temperature of the refrigerant entering the compressor 3, reducing the occurrence of failures or damage to the compressor 3, and at the same time ensuring the long-term cyclic operation of the compressor 3.

[0048] Throttle 8: It is used to control the input of low-temperature and low-pressure liquid refrigerant for heat exchange in the regenerator 7 into the evaporator 1; the main function of the throttle 8 is to adjust the flow rate of the refrigerant to meet the requirements of the carbon dioxide heat pump system under different working conditions.

[0049] Among them, the throttle 8 can also control the low-pressure and low-temperature liquid refrigerant converted by the gas cooler 4 to enter the evaporator 1; the gas-liquid separator 2 can also separate the low-pressure and low-temperature refrigerant converted by the regenerator 7 into gas and liquid. The evaporator 1 and the regenerator 7 are connected through a first pipe, and a first one-way valve 9 is installed on the first pipe. The regenerator 7 and the gas-liquid separator 2 are connected through a second pipe, and the evaporator 1 and the gas-liquid separator 2 are connected through a third pipe. A second one-way valve 10 is installed on the third pipe. The gas cooler 4 and the regenerator 7 are connected through a fourth pipe, and a third one-way valve 11 is installed on the fourth pipe. The gas cooler 4 and the throttle 8 are connected through a fifth pipe, and a fourth one-way valve 12 is installed on the fifth pipe.

[0050] In actual operation, according to actual needs, the following three situations will occur:

[0051] 1. When the pressure and temperature of the refrigerant after passing through the evaporator 1 are within the set standard range, it can directly reach the gas-liquid separator 2 through the third pipe. At this time, both the first one-way valve 9 and the third one-way valve 11 are in the closed state, and the second one-way valve 10 and the fourth one-way valve 12 are open;

[0052] 2. When the pressure and temperature of the refrigerant after passing through the evaporator 1 exceed the set standard range by a small value, the medium-pressure and medium-temperature gas enters the regenerator 7, changing the pressure of the medium-pressure and medium-temperature refrigerant entering the regenerator 7. When the pressure in the regenerator 7 becomes smaller, the temperature of the medium-pressure and medium-temperature refrigerant will also decrease accordingly (in actual situations, each part in the carbon dioxide heat pump system can be regarded as a relatively independent space, but they are also connected in a cycle. According to the ideal gas state equation PV = nRT, where P is the pressure, V is the volume, n is the amount of substance, R is the ideal gas constant, and T is the temperature). Therefore, when the pressure in the regenerator 7 becomes smaller, the medium-pressure and medium-temperature refrigerant will be converted into low-pressure and low-temperature refrigerant, and then the converted low-pressure and low-temperature refrigerant will be compressed after gas-liquid separation. At this time, the first one-way valve 9 and the fourth one-way valve 12 are open, and the second one-way valve 10 and the third one-way valve 11 are closed;

[0053] 3. When the refrigerant after passing through the evaporator 1 far exceeds the designed standard value, open the first one-way valve 9 and the third one-way valve 11, close the second one-way valve 10 and the fourth one-way valve 12, and conduct heat exchange between the two refrigerant flows to reduce the pressure and temperature of the refrigerant entering the compressor 3.

[0054] It should be noted that the temperature, pressure, flow rate and other data of each part in the entire carbon dioxide heat pump system are all under monitoring and control. For example, temperature sensors, pressure sensors, flow rate, flow throttles, etc. are used for control. This is prior art and no redundant introduction will be made here.

[0055] Such as Figure 2 , Figure 3 , Figure 4 and Figure 5As shown in the figure, the regenerator 7 includes a heat exchange barrel 701, a first communication box 702, a second communication box 703, heat exchange tubes 704, a partition plate 705, a low-pressure and low-temperature outlet pipe 706, a low-pressure and low-temperature inlet pipe 707, a high-pressure and medium-temperature inlet pipe 708, and a high-pressure and medium-temperature outlet pipe 709. A working chamber is provided in the heat exchange barrel 701, a first communication cavity is provided in the first communication box 702, and a second communication cavity is provided in the second communication box 703. The first communication box 702 and the second communication box 703 are respectively fixedly installed at both ends of the heat exchange barrel 701. The number of heat exchange tubes 704 is multiple, and the multiple heat exchange tubes 704 are divided into a first batch and a second batch. The number of heat exchange tubes 704 in the first batch and the second batch is the same. The multiple heat exchange tubes 704 are all located in the working chamber of the heat exchange barrel 701. Both ends of the heat exchange tubes 704 respectively penetrate through both ends of the heat exchange barrel 701, and both ends of the heat exchange tubes 704 respectively extend into the first communication cavity and the second communication cavity. The partition plate 705 is fixedly installed in the second communication cavity, and the partition plate 705 can divide the second working chamber into an independent first chamber and a second chamber. The partition plate 705 also separates the end parts of the multiple heat exchange tubes 704 in the first chamber and the second chamber. Both ends of the heat exchange tubes 704 in the first batch are respectively communicated with the first communication cavity and the first chamber, and both ends of the heat exchange tubes 704 in the second batch are respectively communicated with the first communication cavity and the second chamber. The intake end of the low-pressure and low-temperature outlet pipe 706 is communicated with the first chamber, and the outlet end of the low-pressure and low-temperature outlet pipe 706 is communicated with the throttle 8. The outlet end of the low-pressure and low-temperature inlet pipe 707 is communicated with the second chamber, and the intake end of the low-pressure and low-temperature inlet pipe 707 is communicated with the air cooler 4. A pressure control structure is slidably installed in the working chamber of the heat exchange barrel 701. The pressure control structure can divide the working chamber into two independent variable chambers and a pressure control chamber 710, and the pressure control structure can control the space size of the pressure control chamber 710. Both the high-pressure and medium-temperature inlet pipe 708 and the high-pressure and medium-temperature outlet pipe 709 are communicated with the pressure control chamber 710. The high-pressure and medium-temperature inlet pipe 708 is also communicated with the evaporator 1, and the high-pressure and medium-temperature outlet pipe 709 is communicated with the gas-liquid separator. During actual use, when the refrigerant needs to be cooled and depressurized through heat exchange after being converted by the evaporator 1, the low-temperature and low-pressure refrigerant coming out of the air cooler 4 enters the second chamber through the low-pressure and low-temperature inlet pipe 707, then enters the first communication cavity through the heat exchange tubes 704 in the second batch, the refrigerant entering the first communication cavity then reaches the first chamber through the heat exchange tubes 704 in the first batch, and then reaches the throttle 8 through the low-pressure and low-temperature outlet pipe 706. The high-temperature and medium-pressure refrigerant converted by the evaporator 1 enters the pressure control chamber 710 through the high-pressure and medium-temperature inlet pipe 708, and exchanges heat with the low-temperature and low-pressure refrigerant in the heat exchange tubes 704 in the first batch and the second batch. The low-temperature and low-pressure refrigerant after heat exchange is transported to the gas-liquid separator 2 through the high-pressure and medium-temperature outlet pipe 709 and then transported to the compressor 3, thereby completing the pressure reduction and temperature reduction treatment of the refrigerant, ensuring that the compressor 3 can be used normally in a cycle, and reducing the protection mechanism for overheating shutdown.

[0056] AsFigure 2 , Figure 4 and Figure 5 As shown in Figure 2 , Figure 4 and Figure 5 , the pressure control structure includes a pressure control plate 711 and an electric push rod 712; the pressure control plate 711 is slidably installed in the working chamber of the heat exchange barrel 701, and a plurality of heat exchange tubes 704 all penetrate through the pressure control plate 711. The plurality of heat exchange tubes 704 are arranged in parallel. The electric push rod 712 is fixedly installed on the first communication box 702. The output shaft of the electric push rod 712 slidably penetrates through the end of the first communication box 702 and the heat exchange barrel 701 and extends into the working chamber to be fixedly connected with the pressure control plate 711. A telescopic tube 713 is installed through the pressure control plate 711. The telescopic tube 713 is slidably inserted into the high-pressure medium-temperature inlet pipe 708. The outer diameter of the telescopic tube 713 is the same as the inner diameter of the high-pressure medium-temperature inlet pipe 708. The refrigerant needs to pass through the entire pressure control chamber 710 from the high-pressure medium-temperature inlet pipe 708 to the high-pressure medium-temperature outlet pipe 709, which can ensure that the high-pressure medium-temperature refrigerant can fully exchange heat to achieve the effect of pressure reduction and temperature reduction. When the medium-pressure medium-temperature refrigerant needs to be depressurized and cooled, the medium-pressure medium-temperature refrigerant enters the pressure control chamber 710, and the electric push rod 712 drives the pressure control plate 711 to slide in the working chamber, so that the volume of the pressure control chamber 710 increases. However, the amount of refrigerant in the pressure control chamber 710 remains unchanged, so that the pressure in the pressure control chamber 710 becomes smaller, the pressure of the refrigerant becomes smaller, and its temperature also decreases accordingly, so that the refrigerant achieves the effect of temperature reduction and pressure reduction. The amount of refrigerant in the pressure control chamber 710 can be controlled by the control system; in addition, when adjusting the size of the pressure control chamber 710, the length of the heat exchange tube 704 located in the pressure control chamber 710 also changes accordingly, thereby changing the heat exchange time and controlling the heat exchange effect.

[0057] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A carbon dioxide heat pump system, characterized in that: include: Evaporator (1): The evaporator (1) is the cold end of the CO2 heat pump system, absorbing heat to cool the air; Gas-liquid separator (2): The gas-liquid separator (2) can separate the gaseous and liquid refrigerant from the evaporator (1); Compressor (3): The compressor (3) is the hot end of the CO2 heat pump system, which compresses the low-temperature and low-pressure refrigerant from the gas-liquid separator (2) into a high-temperature and high-pressure refrigerant; Air cooler (4): the air cooler (4) is the hot end of the carbon dioxide heat pump system and is used to release heat from the high-temperature and high-pressure refrigerant compressed by the compressor (3); No. 1 fan (5): No. 1 fan (5) provides air flow for the air cooler (4) to help the refrigerant release heat; No. 2 fan (6): used to increase the air flow speed on the surface of the evaporator (1) and improve the heat exchange efficiency; Regenerator (7): the regenerator (7) is capable of performing heat exchange between the low-temperature and low-pressure liquid refrigerant that has passed through the air cooler (4) and the high-pressure and medium-temperature refrigerant that has passed through the evaporator (1). The regenerator (7) is capable of converting the high-pressure and medium-temperature refrigerant into the low-pressure and low-temperature refrigerant. The regenerator (7) is also capable of adjusting the pressure inside the regenerator so that the high-pressure and medium-temperature refrigerant is converted into the low-pressure and low-temperature refrigerant. Throttle (8): used to control the low-temperature and low-pressure liquid refrigerant for heat exchange in the regenerator (7) to be input into the evaporator (1); The throttle (8) can also control the low-pressure and low-temperature liquid refrigerant converted by the air cooler (4) to enter the evaporator (1); and the gas-liquid separator (2) can also perform gas-liquid separation on the low-pressure and low-temperature refrigerant converted by the regenerator (7).

2. A carbon dioxide heat pump system according to claim 1, characterized in that: The regenerator (7) comprises a heat exchange barrel (701), a No. 1 connecting box (702), a No. 2 connecting box (703), a heat exchange tube (704), a partition (705), a low-pressure and low-temperature outlet tube (706), a low-pressure and low-temperature inlet tube (707), a high-pressure and medium-temperature inlet tube (708) and a high-pressure and medium-temperature outlet tube (709); a working chamber is provided in the heat exchange barrel (701), a No. 1 connecting chamber is provided in the No. 1 connecting box (702), a No. 2 connecting chamber is provided in the No. 2 connecting box (703), the No. 1 connecting box (702) and the No. 2 connecting box (703) are respectively fixedly mounted at two ends of the heat exchange barrel (701), and the number of the heat exchange tubes (704) is multiple, and the multiple The heat exchange tubes (704) are all located in the I-shaped cavity of the heat exchange barrel (701), the two ends of the heat exchange tubes (704) respectively pass through the two ends of the heat exchange barrel (701), and the two ends of the heat exchange tubes (704) respectively extend into the No. 1 connecting cavity and the No. 2 connecting cavity, the partition (705) is fixedly installed in the No. 2 connecting cavity, and the partition (705) can separate the No. 2 working cavity into a No. 1 cavity and a No. 2 cavity that are independent of each other, and the partition (705) also separates the ends of the plurality of heat exchange tubes (704) into the No. 1 cavity and the No. 2 cavity, the air inlet end of the low-pressure and low-temperature outlet tube (706) is in communication with the No. 1 cavity, and the air outlet end of the low-pressure and low-temperature outlet tube (706) is in communication with the No. 1 cavity, and the air outlet end of the low-pressure and low-temperature outlet tube (706) is in communication with the throttle (8); The air outlet end of the low-pressure and low-temperature inlet pipe (707) is in communication with the second chamber, and the air inlet end of the low-pressure and low-temperature inlet pipe (707) is in communication with the air cooler (4); A pressure control structure is slidably installed in the working chamber of the heat exchange barrel (701), the pressure control structure being capable of dividing the working chamber into two independent variable chambers and a pressure control chamber (710), and the pressure control structure being capable of controlling the spatial size of the pressure control chamber (710); The high-pressure medium-temperature inlet pipe (708) and the high-pressure medium-temperature outlet pipe (709) are both connected to the pressure control chamber (710); the high-pressure medium-temperature inlet pipe (708) is also connected to the evaporator (1); and the high-pressure medium-temperature outlet pipe (709) is connected to the gas-liquid separator.

3. A carbon dioxide heat pump system according to claim 2, characterized in that: The pressure control structure comprises a pressure control plate (711) and an electric push rod (712); the pressure control plate (711) is slidably mounted in the working chamber of the heat exchange barrel (701); the plurality of heat exchange tubes (704) all pass through the pressure control plate (711); the plurality of heat exchange tubes (704) are arranged in parallel with each other; the electric push rod (712) is fixedly mounted on a No. 1 connecting box (702); an output shaft of the electric push rod (712) slidably passes through the No. 1 connecting box (702) and the end of the heat exchange barrel (701) and extends into the working chamber to be fixedly connected to the pressure control plate (711).

4. A carbon dioxide heat pump system according to claim 3, characterized in that: A telescopic tube (713) is installed through the pressure control plate (711), and the telescopic tube (713) is slidably inserted into the high-pressure medium-temperature inlet pipe (708). The outer diameter of the telescopic tube (713) is the same as the inner diameter of the high-pressure medium-temperature inlet pipe (708).

5. The carbon dioxide heat pump system according to claim 1, characterized in that: The evaporator (1) and the regenerator (7) are connected via a No. 1 pipe, a No. 1 one-way valve (9) is installed on the No. 1 pipe, and the regenerator (7) and the gas-liquid separator (2) are connected via a No. 2 pipe.

6. A carbon dioxide heat pump system according to claim 5, characterized in that: The evaporator (1) and the gas-liquid separator (2) are connected via a No. 3 pipe, and a No. 2 check valve (10) is installed on the No. 3 pipe.

7. A carbon dioxide heat pump system according to claim 6, characterized in that: The air cooler (4) and the regenerator (7) are connected via a No. 4 pipe, and a No. 3 check valve (11) is installed on the No. 4 pipe.

8. A carbon dioxide heat pump system according to claim 7, characterized in that: The air cooler (4) and the throttle (8) are connected via a No. 5 pipe, and a No. 4 check valve (12) is installed on the No. 5 pipe.

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