Outdoor unit and air conditioning system

Abstract

The utility model provides an outdoor unit and an air conditioning system, the outdoor unit is provided with three multi-way reversing valves arranged in parallel, namely a first multi-way reversing valve, a second multi-way reversing valve and a third multi-way reversing valve, and the three multi-way reversing valves respectively and independently control a heat storage module, an outdoor heat exchanger and an indoor unit; when the indoor unit conducts heating, the first multi-way reversing valve is powered on, and the second multi-way reversing valve and the third multi-way reversing valve are powered off, so that a part of refrigerant flowing out of a liquid pipe of the indoor unit sequentially passes through the outdoor heat exchanger and the second multi-way reversing valve to flow to an air suction port of the compressor. And the other part of the refrigerant sequentially passes through the heat storage module and the third multi-way reversing valve to flow to an air suction port of the compressor, in the process, the outdoor heat exchanger and the heat storage module are both used as evaporators, the heating capacity can be effectively improved, and particularly in the environment with the low outdoor temperature, attenuation of the heating capacity of the whole machine is reduced or delayed.

Description

Technical Field

[0001] The utility model belongs to the technical field of air-conditioning equipment, and more specifically, relates to an outdoor unit and an air-conditioning system. Background Art

[0002] With the gradual improvement of living needs and global climate anomalies, people's demand for low-temperature heating is increasing. Under the condition of heat pump air conditioning heating, the outdoor heat exchanger is used as an evaporator, and the surface temperature is lower than the ambient temperature. After running for a period of time, frost will appear on the surface. After the frost layer is formed, the heat transfer resistance of the heat exchanger will increase, resulting in a decrease in the heat exchange efficiency of the outdoor heat exchanger. The attenuation is more serious in low temperature and high humidity environments, and it is often difficult to meet the heating demand.

[0003] In order not to affect the heating effect, a solution that can provide continuous heating has emerged in the prior art. Specifically, a heat storage module is connected to the refrigerant circulation loop through multiple branches, and the heat storage and heat release of the heat storage module are flexibly realized by switching the on and off states of each branch, and the heating state of the indoor unit is ensured. However, this design makes the overall structure of the system more complicated, requiring the design of more pipes connected to the heat storage module and more valves and pipes connected to the outdoor heat exchanger, while increasing the system's failure points and reducing the system's reliability. Utility Model Content

[0004] The utility model aims to provide an outdoor unit and an air conditioning system, which can more reliably solve the problem of large heating attenuation during low-temperature heating.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] The utility model provides an outdoor unit, comprising a heat storage module and an outdoor heat exchanger, and a compressor, which are respectively connected to the liquid pipe of the indoor unit. The utility model is characterized in that the outdoor unit also comprises: a first multi-way reversing valve, a second multi-way reversing valve and a third multi-way reversing valve arranged in parallel, the first multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the air pipe of the indoor unit, the second multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the outdoor heat exchanger, and the third multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the heat storage module.

[0007] Further, the first multi-way reversing valve, the second multi-way reversing valve and the third multi-way reversing valve are four-way reversing valves.

[0008] Furthermore, it also includes a subcooler, which is provided with a first branch and a second branch, the first end of the first branch is connected to the indoor unit liquid pipe, the second end of the first branch is respectively connected to the heat storage module and the outdoor heat exchanger, the first end of the second branch is connected in series with a subcooling throttle valve and the second end of the first branch, and the second end of the second branch is connected in series with a subcooling control valve and the suction port of the compressor.

[0009] Furthermore, the compressor is also provided with an enthalpy increase port, and the outdoor unit also includes an enthalpy increase branch, the first end of the enthalpy increase branch is connected between the second end of the second branch and the subcooling control valve, and the second end of the enthalpy increase branch is connected to the enthalpy increase port of the compressor.

[0010] Furthermore, a muffler is provided on the enthalpy increase branch.

[0011] Furthermore, a heat storage throttle valve is provided between the heat storage module and the supercooler.

[0012] Furthermore, a heating throttle valve is provided between the outdoor heat exchanger and the subcooler.

[0013] Furthermore, the exhaust port of the compressor is connected to an oil separator, and the refrigerant delivered from the exhaust port of the compressor passes through the oil separator.

[0014] Furthermore, the air intake port of the compressor is connected to a gas-liquid separator, and all refrigerants sent to the air intake port of the compressor pass through the gas-liquid separator.

[0015] The utility model also provides an air conditioning system, comprising the outdoor unit and the indoor unit as described above, wherein the indoor unit is connected to the outdoor unit through an indoor unit air pipe and an indoor unit liquid pipe.

[0016] The beneficial effects of the outdoor unit and air-conditioning system provided by the utility model are as follows: compared with the prior art, the outdoor unit provided by the utility model has three multi-way reversing valves arranged in parallel, namely a first multi-way reversing valve, a second multi-way reversing valve and a third multi-way reversing valve, and the three multi-way reversing valves independently control the heat storage module, the outdoor heat exchanger and the indoor unit, respectively, with complementary interference, and can flexibly switch the flow direction of the refrigerant, so that the system can respond quickly in different working modes (such as heating, heat storage, defrosting, etc.), and at the same time, such a design can reduce additional pipes or valves connected to the heat storage module and the outdoor heat exchanger, making the system structure more compact and simplified, which not only reduces the manufacturing and installation costs, but also improves the reliability of the system. Furthermore, when the indoor unit is heating, the first multi-way reversing valve is energized and the second and third multi-way reversing valves are de-energized, allowing a portion of the refrigerant flowing out of the indoor unit liquid pipe to pass through the outdoor heat exchanger and the second multi-way reversing valve in sequence to flow to the suction port of the compressor, and another portion of the refrigerant to pass through the heat storage module and the third multi-way reversing valve in sequence to flow to the suction port of the compressor. In this process, both the outdoor heat exchanger and the heat storage module are used as evaporators, which can effectively increase the heating capacity, especially in an environment with low outdoor temperature, reducing or delaying the attenuation of the overall heating capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 A schematic diagram of an air conditioning system provided by a preferred embodiment of the utility model when in cooling mode;

[0019] Figure 2 A schematic diagram of an air conditioning system provided by a preferred embodiment of the utility model when in a heating and heat storage mode;

[0020] Figure 3 A schematic diagram of an air conditioning system provided by a preferred embodiment of the utility model when in a heating and defrosting mode;

[0021] Figure 4 A schematic diagram of an air conditioning system provided by a preferred embodiment of the utility model in the first stage of a low-temperature heating enthalpy spraying mode;

[0022] Among them, the main marks of the drawings in the figure are:

[0023] 11. Liquid pipe; 12. Gas pipe; 21. Heat storage module; 22. Outdoor heat exchanger; 23. Compressor; 24. Subcooler;

[0024] 121, first valve; 122, second valve;

[0025] 211, heat storage throttle valve; 221, heating throttle valve;

[0026] 251, a first multi-way reversing valve; 252, a second multi-way reversing valve; 253, a third multi-way reversing valve;

[0027] 261, subcooling throttle valve; 262, subcooling control valve;

[0028] 27. Enthalpy increase branch; 271. Muffler;

[0029] 28. Oil separator; 29. ​​Gas-liquid separator. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] With the gradual improvement of living needs and global climate anomalies, people's demand for low-temperature heating is increasing. Under the heating condition of heat pump air conditioning, the outdoor heat exchanger is used as an evaporator, and the surface temperature is lower than the ambient temperature. After running for a period of time, frost will appear on the surface. After the frost layer is formed, the heat transfer thermal resistance of the heat exchanger will increase, resulting in a decrease in the heat exchange efficiency of the outdoor heat exchanger. The attenuation is more serious in low temperature and high humidity environments, and it is often difficult to meet the heating demand. Therefore, when the heat pump system is running in heating mode, it is necessary to defrost in time according to the temperature of the outdoor coil sensor to detect the frost layer. The defrosting process will be converted to cooling mode. The indoor unit can no longer output heat, but will absorb the indoor ambient temperature, which seriously affects the customer experience. The existing patent document CN111322784A proposes that a double four-way valve controls two outdoor heat exchangers respectively, and defrosts in turn during defrosting, but this will also reduce the heating effect.

[0032] In this regard, the utility model provides an outdoor unit and an air-conditioning system, which can solve the problem of large attenuation of low-temperature heating and the effect of defrosting on the heating effect of the heat pump.

[0033] See also Figures 1 to 4As shown, the outdoor unit provided by the preferred embodiment of the utility model includes: a heat storage module 21 and an outdoor heat exchanger 22 connected to the liquid pipe 11 of the indoor unit, and a compressor 23 provided with an exhaust port and an air intake port, and also includes: a first multi-way reversing valve 251, a second multi-way reversing valve 252 and a third multi-way reversing valve 253 arranged in parallel, the first multi-way reversing valve 251 is respectively connected to the exhaust port of the compressor 23, the air intake port of the compressor 23 and the air pipe 12 of the indoor unit, the second multi-way reversing valve 252 is respectively connected to the exhaust port of the compressor 23, the air intake port of the compressor 23 and the outdoor heat exchanger 22, and the third multi-way reversing valve 253 is respectively connected to the exhaust port of the compressor 23, the air intake port of the compressor 23 and the heat storage module 21.

[0034] The outdoor unit provided by the utility model has three multi-way reversing valves arranged in parallel, namely the first multi-way reversing valve 251, the second multi-way reversing valve 252 and the third multi-way reversing valve 253. The three multi-way reversing valves independently control the heat storage module 21, the outdoor heat exchanger 22 and the indoor unit, respectively, and complement each other. The flow direction of the refrigerant can be flexibly switched, so that the system can respond quickly in different working modes (such as heating, heat storage, defrosting, etc.). At the same time, such a design can reduce additional pipes or valves connected to the heat storage module 21 and the outdoor heat exchanger 22, making the system structure more compact and simplified, which not only reduces the manufacturing and installation costs, but also improves the reliability of the system. Furthermore, when the indoor unit is heating, the first multi-way reversing valve 251 is energized and the second multi-way reversing valve 252 and the third multi-way reversing valve 253 are de-energized, allowing a portion of the refrigerant flowing out of the liquid pipe 11 of the indoor unit to pass through the outdoor heat exchanger 22 and the second multi-way reversing valve 252 in sequence to flow to the suction port of the compressor 23, and another portion of the refrigerant to pass through the heat storage module 21 and the third multi-way reversing valve 253 in sequence to flow to the suction port of the compressor 23. In this process, the outdoor heat exchanger 22 and the heat storage module 21 are both used as evaporators, which can effectively increase the heating amount, especially in an environment with low outdoor temperature, reducing or delaying the attenuation of the entire heating amount.

[0035] In a preferred embodiment of the utility model, the first multi-way reversing valve 251, the second multi-way reversing valve 252 and the third multi-way reversing valve 253 are four-way reversing valves.

[0036] like Figure 1 As shown, the first multi-way reversing valve 251, the second multi-way reversing valve 252 and the third multi-way reversing valve 253 are all four-way reversing valves, that is, they all include four interfaces (a first interface D, a second interface E, a third interface S and a fourth interface C).

[0037] The first interface D of the first multi-way reversing valve 251 is connected to the exhaust port of the compressor 23, the second interface E of the first multi-way reversing valve 251 is connected to the liquid pipe 11 of the indoor unit, the third interface S of the first multi-way reversing valve 251 is connected to the suction port of the compressor 23, and the fourth interface C of the first multi-way reversing valve 251 is connected to the third interface S of the first multi-way reversing valve 251 through a capillary.

[0038] The first interface D of the second multi-way reversing valve 252 is connected to the exhaust port of the compressor 23, the second interface E of the second multi-way reversing valve 252 is connected to the third interface S of the second multi-way reversing valve 252 through a capillary, the third interface S of the second multi-way reversing valve 252 is connected to the intake port of the compressor 23, and the fourth interface C of the second multi-way reversing valve 252 is connected to the outdoor heat exchanger 22.

[0039] The first interface D of the third multi-way reversing valve 253 is connected to the exhaust port of the compressor 23, the second interface E of the third multi-way reversing valve 253 is connected to the heat storage module 21, the third interface S of the third multi-way reversing valve 253 is connected to the intake port of the compressor 23, and the fourth interface C of the third multi-way reversing valve 253 is connected to the third interface S of the third multi-way reversing valve 253 through a capillary.

[0040] In the outdoor unit provided in the preferred embodiment of the utility model, the three multi-way reversing valves arranged in parallel (the first multi-way reversing valve 251, the second multi-way reversing valve 252 and the third multi-way reversing valve 253) are all four-way reversing valves, which are used to change the flow direction of the refrigerant in the heat pump system, so that the heat storage module 21 is switched to evaporator or condenser operation, and the outdoor heat exchanger 22 is switched to evaporator or condenser operation, thereby realizing cooling, heating, heat storage and defrosting operations.

[0041] Of course, in other embodiments, at least one of the first multi-way reversing valve 251 , the second multi-way reversing valve 252 and the third multi-way reversing valve 253 may be a two-way reversing valve.

[0042] In a preferred embodiment of the utility model, the outdoor unit also includes a subcooler 24, the subcooler 24 is provided with a first branch and a second branch, the first end of the first branch is connected to the liquid pipe 11 of the indoor unit, the second end of the first branch is respectively connected to the heat storage module 21 and the outdoor heat exchanger 22, the first end of the second branch is connected in series with the subcooling throttle valve 261 and the second end of the first branch, and the second end of the second branch is connected in series with the subcooling control valve 262 and the suction port of the compressor 23.

[0043] The subcooling throttle valve 261 may be an electronic expansion valve, and the subcooling control valve 262 may be a one-way valve or a solenoid valve. In other embodiments, the subcooling throttle valve 261 may be replaced by an electronic expansion valve, and valve controls such as the subcooling control valve 262 may be eliminated.

[0044] In the outdoor unit provided in the preferred embodiment of the utility model, a subcooler 24 is provided to play a role of secondary condensation, thereby improving the subcooling degree of the air-conditioning system, and is particularly suitable for air-conditioning systems with relatively long connecting pipes between the indoor unit and the outdoor unit.

[0045] In a preferred embodiment of the utility model, the compressor 23 is also provided with an enthalpy increase port, and the outdoor unit also includes an enthalpy increase branch 27, the first end of the enthalpy increase branch 27 is connected between the second end of the second branch and the subcooling control valve 262, and the second end of the enthalpy increase branch 27 is connected to the enthalpy increase port of the compressor 23.

[0046] In the outdoor unit provided in the preferred embodiment of the utility model, the compressor 23 has an enthalpy increase port and an enthalpy increase branch 27, which allows the refrigerant to supplement the compressor 23 with air injection enthalpy through the enthalpy increase branch 27, thereby increasing the heating amount.

[0047] In a preferred embodiment of the utility model, a muffler 271 is provided on the enthalpy increase branch 27 .

[0048] In the outdoor unit provided in the preferred embodiment of the utility model, a muffler 271 is provided on the enthalpy increase branch 27 to reduce noise.

[0049] In a preferred embodiment of the utility model, a heat storage throttle valve 211 is provided between the heat storage module 21 and the supercooler 24. The heat storage throttle valve 211 can be an electronic expansion valve.

[0050] In the outdoor unit provided in the preferred embodiment of the utility model, the heat storage throttle valve 211 can be used to control the flow of the refrigerant flowing to the heat storage module 21 or the subcooler 24, which can optimize the heat storage and heat release process and improve the heat exchange efficiency of the refrigerant.

[0051] In a preferred embodiment of the utility model, a heating throttle valve 221 is provided between the outdoor heat exchanger 22 and the subcooler 24 .

[0052] In the outdoor unit provided in the preferred embodiment of the utility model, the heating throttle valve 221 can be used to control the flow of the refrigerant flowing to the outdoor heat exchanger 22 or the subcooler 24, which can be adapted to different heating requirements and help improve the stability of the air-conditioning system.

[0053] In the preferred embodiment of the utility model, the exhaust port of the compressor 23 is connected to an oil separator 28, and the refrigerant sent out from the exhaust port of the compressor 23 passes through the oil separator 28. At the same time, the oil return port of the oil separator 28 is connected to the air intake port of the compressor 23 through a reflux branch, and an oil return capillary is provided on the oil return branch, and the lubricating oil in the oil separator 28 is sent back to the compressor 23 through the oil return branch.

[0054] In the outdoor unit provided in the preferred embodiment of the utility model, the oil droplets in the gaseous refrigerant discharged from the compressor 23 are separated by the oil separator 28, thereby reducing the deposition of oil on the surface of the outdoor heat exchanger 22 and ensuring the cooling or heating effect of the air-conditioning system.

[0055] In a preferred embodiment of the utility model, the air intake port of the compressor 23 is connected to a gas-liquid separator 29 , and all refrigerants sent to the air intake port of the compressor 23 pass through the gas-liquid separator 29 .

[0056] In the outdoor unit provided in the preferred embodiment of the utility model, the liquid refrigerant and the gaseous refrigerant are separated by the gas-liquid separator 29 to ensure that only the gaseous refrigerant enters the compressor 23, while the liquid refrigerant is separated out, which helps to protect the compressor 23 from damage and extend the service life of the compressor 23.

[0057] The air conditioning system provided by the preferred embodiment of the utility model includes an outdoor unit and an indoor unit. The indoor unit is connected to the outdoor unit through an air pipe 12 and a liquid pipe 11 to form a refrigerant circulation loop.

[0058] The structure of the outdoor unit has been described in detail above and will not be repeated here. The indoor unit includes at least one indoor heat exchanger. When there are multiple indoor heat exchangers, multiple indoor heat exchangers are arranged in parallel. A first valve 121 is provided on the gas pipe 12 of the indoor unit, and a second valve 122 is provided on the liquid pipe 11 of the indoor unit. When the first valve 121 and the second valve 122 are closed, the entire indoor unit does not participate in the refrigerant circulation.

[0059] In the air-conditioning system provided by the preferred embodiment of the utility model, an outdoor unit is provided with three multi-way reversing valves arranged in parallel, namely, a first multi-way reversing valve 251, a second multi-way reversing valve 252 and a third multi-way reversing valve 253. The three multi-way reversing valves independently control the heat storage module 21, the outdoor heat exchanger 22 and the indoor heat exchanger, respectively, to achieve cooling, heating, heat storage and defrosting operations, while being able to solve the problems of large attenuation of low-temperature heating and the influence of defrosting on the heating effect of the heat pump.

[0060] For ease of understanding, the following Figures 1 to 4 The air conditioning system and different working modes provided by the preferred embodiment of the utility model are described in detail.

[0061] like Figure 1 As shown, the air conditioning system includes an indoor unit and an outdoor unit, and the outdoor unit is respectively connected to the gas pipe 12 of the indoor unit and the liquid pipe 11 of the indoor unit to form a refrigerant circulation loop.

[0062] The indoor unit mainly includes an indoor heat exchanger.

[0063] The outdoor unit mainly includes a compressor 23 with an enthalpy increase port, a heat storage module 21, an outdoor heat exchanger 22, a subcooler 24, three four-way reversing valves, an oil separator 28, and a gas-liquid separator 29. Among them, the three four-way reversing valves (the first multi-way reversing valve 251, the second multi-way reversing valve 252, and the third multi-way reversing valve 253) each include four interfaces (a first interface D, a second interface E, a third interface S, and a fourth interface C).

[0064] The oil separator 28 is connected to the exhaust port of the compressor 23 , and the gas-liquid separator 29 is connected to the intake port of the compressor 23 .

[0065] The subcooler 24 includes a first branch and a second branch, wherein the first end of the first branch is connected to the liquid pipe 11 of the indoor unit, the second end of the first branch is connected in series with the subcooling throttle valve 261 and the first end of the second branch, the second end of the first branch is also connected to the heat storage module 21 and the outdoor heat exchanger 22 respectively, and the second end of the second branch is connected in series with the subcooling control valve 262 and the air intake port of the compressor 23. The subcooling throttle valve 261 is an electronic expansion valve, and the subcooling control valve 262 is a solenoid valve.

[0066] The first interface D of the first multi-way reversing valve 251 is connected to the oil separator 28, the second interface E of the first multi-way reversing valve 251 is connected to the liquid pipe 11 of the indoor unit, the third interface S of the first multi-way reversing valve 251 is connected to the gas-liquid separator 29, and the fourth interface C of the first multi-way reversing valve 251 is connected to the third interface S of the first multi-way reversing valve 251 through a capillary.

[0067] The first interface D of the second multi-way reversing valve 252 is connected to the oil separator 28, the second interface E of the second multi-way reversing valve 252 is connected to the third interface S of the second multi-way reversing valve 252 through a capillary, the third interface S of the second multi-way reversing valve 252 is connected to the gas-liquid separator 29, and the fourth interface C of the second multi-way reversing valve 252 is connected to the outdoor heat exchanger 22.

[0068] The first interface D of the third multi-way reversing valve 253 is connected to the oil separator 28, the second interface E of the third multi-way reversing valve 253 is connected to the heat storage module 21, the third interface S of the third multi-way reversing valve 253 is connected to the gas-liquid separator 29, and the fourth interface C of the third multi-way reversing valve 253 is connected to the third interface S of the third multi-way reversing valve 253 through a capillary.

[0069] One end of the heat storage module 21 is connected to the third multi-way reversing valve 253 , and the other end is connected in series with the heat storage throttle valve 211 and the subcooler 24 , wherein the heat storage throttle valve 211 is an electronic expansion valve.

[0070] One end of the outdoor heat exchanger 22 is connected to the second multi-way reversing valve 252, and the other end is connected in series with the heating throttle valve 221 and the subcooler 24, wherein the heating throttle valve 221 is an electronic expansion valve.

[0071] One end of the enthalpy increase branch 27 is connected between the subcooler 24 and the subcooling control valve 262 , and the other end is connected to the enthalpy increase port of the compressor 23 . A muffler 271 is provided on the enthalpy increase branch 27 .

[0072] After the refrigerant flowing out of the heat storage module 21 merges with the refrigerant flowing out of the outdoor heat exchanger 22, the main path is connected to the liquid pipe 11 of the indoor unit through the first branch of the subcooler 24. The branch passes through the subcooling throttle valve 261 and the second branch of the subcooler 24 in turn and then is divided into two. One path passes through the enthalpy increase branch 27 and flows into the compressor 23 for enthalpy injection, and the other path passes through the subcooling control valve 262 and flows into the gas-liquid separator 29.

[0073] like Figure 1 As shown, when the air-conditioning system is in cooling mode, the first multi-way reversing valve 251 is powered off, so that the first interface D of the first multi-way reversing valve 251 is connected to its fourth interface C, and the second interface E of the first multi-way reversing valve 251 is connected to its third interface S; the second multi-way reversing valve 252 is powered off, so that the first interface D of the second multi-way reversing valve 252 is connected to its fourth interface C, and the second interface E of the second multi-way reversing valve 252 is connected to its third interface S; the third multi-way reversing valve 253 is powered off, so that the first interface D of the third multi-way reversing valve 253 is connected to its fourth interface C, and the second interface E of the third multi-way reversing valve 253 is connected to its third interface S.

[0074] The indoor heat exchanger is switched to an evaporator, and the outdoor heat exchanger 22 is switched to a condenser.

[0075] The refrigerant discharged from the exhaust port of the compressor 23 flows into the indoor heat exchanger through the oil separator 28, the second multi-way reversing valve 252, the outdoor heat exchanger 22, the heating throttle valve 221, the subcooler 24 and the liquid pipe 11 of the indoor unit. The refrigerant discharged from the indoor heat exchanger returns to the air intake port of the compressor 23 through the air pipe 12 of the indoor unit, the first multi-way reversing valve 251 and the gas-liquid separator 29.

[0076] like Figure 2As shown, when the air-conditioning system is in the heating and heat storage mode, the first multi-way reversing valve 251 is energized, so that the first interface D of the first multi-way reversing valve 251 is connected to its second interface E, and the third interface S of the first multi-way reversing valve 251 is connected to its fourth interface C; the second multi-way reversing valve 252 is energized, so that the first interface D of the second multi-way reversing valve 252 is connected to its second interface E, and the third interface S of the second multi-way reversing valve 252 is connected to its fourth interface C; the third multi-way reversing valve 253 is energized, so that the first interface D of the third multi-way reversing valve 253 is connected to its second interface E, and the third interface S of the third multi-way reversing valve 253 is connected to its fourth interface C.

[0077] The refrigerant discharged from the exhaust port of the compressor 23 is divided into two parts through the oil separator 28. One path passes through the first multi-way reversing valve 251 and the air pipe 12 of the indoor unit in turn and flows into the indoor heat exchanger. The refrigerant discharged from the indoor heat exchanger passes through the liquid pipe 11 of the indoor unit and the subcooler 24 in turn and then merges with the heat storage branch; the other path passes through the third multi-way reversing valve 253 in turn and flows into the heat storage module 21 for heat storage. After the heat storage is completed, it passes through the heat storage throttle valve 211 and merges with the main path, and then enters the outdoor heat exchanger 22 after throttling by the heating throttle valve 221 to evaporate and absorb heat. Then the low-temperature and low-pressure refrigerant passes through the second multi-way reversing valve 252 and the gas-liquid separator 29 in turn and returns to the air intake of the compressor 23.

[0078] like Figure 3 As shown, when the air-conditioning system is in the heating and defrosting mode, the first multi-way reversing valve 251 is energized, so that the first interface D of the first multi-way reversing valve 251 is connected to its second interface E, and the third interface S of the first multi-way reversing valve 251 is connected to its fourth interface C; the second multi-way reversing valve 252 is de-energized, so that the first interface D of the second multi-way reversing valve 252 is connected to its fourth interface C, and the second interface E of the second multi-way reversing valve 252 is connected to its third interface S; the third multi-way reversing valve 253 is de-energized, so that the first interface D of the third multi-way reversing valve 253 is connected to its fourth interface C, and the second interface E of the third multi-way reversing valve 253 is connected to its third interface S.

[0079] The refrigerant discharged from the exhaust port of the compressor 23 is divided into two parts through the oil separator 28. One part passes through the first multi-way reversing valve 251 and the gas pipe 12 of the indoor unit in sequence and flows into the indoor heat exchanger. The refrigerant discharged from the indoor heat exchanger passes through the liquid pipe 11 of the indoor unit and the subcooler 24 in sequence and then merges with the heat storage branch. The other part passes through the second multi-way reversing valve 252 in sequence and flows into the indoor heat exchanger for heat exchange and defrosting, and then passes through the heating throttle valve 221 and merges with the main road, and then passes through the heat storage throttle valve 211 in sequence to throttle and reduce the pressure and then enter the heat storage module 21 for heat absorption. Finally, the low-temperature and low-pressure refrigerant passes through the third multi-way reversing valve 253 and the gas-liquid separator 29 in sequence and returns to the air intake of the compressor 23. In this way, the indoor unit continues to heat during the defrosting process, ensuring the stability of the indoor environment temperature, avoiding uncomfortable experience for users, and solving the problem that defrosting affects the heating effect of the heat pump.

[0080] When the air conditioning system is in the low-temperature heating spray enthalpy mode, it is divided into the following two stages:

[0081] like Figure 4 As shown, in the first stage: the first multi-way reversing valve 251 is energized, so that the first interface D of the first multi-way reversing valve 251 is connected to the second interface E thereof, and the third interface S of the first multi-way reversing valve 251 is connected to the fourth interface C thereof; the second multi-way reversing valve 252 is deenergized, so that the first interface D of the second multi-way reversing valve 252 is connected to the fourth interface C thereof, and the second interface E of the second multi-way reversing valve 252 is connected to the third interface S thereof; the third multi-way reversing valve 253 is energized, so that the first interface D of the third multi-way reversing valve 253 is connected to the second interface E thereof, and the third interface S of the third multi-way reversing valve 253 is connected to the fourth interface C thereof.

[0082] The indoor heat exchanger is switched to a condenser, the outdoor heat exchanger 22 is switched to an evaporator, and the heat storage module 21 is switched to a condenser.

[0083] Part of the refrigerant discharged from the exhaust port of the compressor 23 flows into the indoor heat exchanger through the oil separator 28, the first multi-way reversing valve 251 and the air pipe 12 of the indoor unit in sequence. At this time, the indoor heat exchanger switches to the condenser for heating. The cooled refrigerant flows into the subcooler 24 through the liquid pipe 11 of the indoor unit. The refrigerant passing through the subcooler 24 is divided into two parts. One part flows into the outdoor heat exchanger 22 through the heating throttle valve 221 for evaporation and heat absorption, and then returns to the air intake of the compressor 23 through the second multi-way reversing valve 252 and the gas-liquid separator 29 in sequence. The other part passes through the subcooling throttle valve 261 (the subcooling control valve 262 is closed at this time) and the muffler 271 in sequence to enter the enthalpy increase port of the compressor 23 to supplement the compressor 23 with air and spray enthalpy, thereby increasing the heating capacity. Part of the refrigerant discharged from the exhaust port of the compressor 23 flows into the heat storage module 21 through the third multi-way reversing valve 253 for heat storage.

[0084] Phase 2: After the heating has been running for a period of time (which can be set as time constant A), when it is detected that the heating amount decays greatly or the low pressure is particularly low (heating amount < Q or low pressure < Pd), the third multi-way reversing valve 253 is powered off, so that the first interface D of the third multi-way reversing valve 253 is connected to its fourth interface C, and the second interface E of the third multi-way reversing valve 253 is connected to its third interface S. The heat storage module 21 is switched to an evaporator.

[0085] The refrigerant passing through the subcooler 24 is divided into two parts. One part flows into the outdoor heat exchanger 22 through the heating throttle valve 221 for evaporation and heat absorption, and then passes through the second multi-way reversing valve 252 and the gas-liquid separator 29 in sequence to return to the air intake of the compressor 23; the other part flows into the heat storage module 21 through the heat storage throttle valve 211 for evaporation and heat absorption, and then passes through the third multi-way reversing valve 253 and the gas-liquid separator 29 in sequence to return to the air intake of the compressor 23. This is equivalent to having two evaporators (outdoor heat exchanger 22 + heat storage module 21) in the outdoor unit, which greatly improves the heating capacity, reduces or delays the attenuation of the heating capacity of the whole unit, and effectively solves the problem of large attenuation of low-temperature heating.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An outdoor unit, comprising a heat storage module and an outdoor heat exchanger respectively connected to the liquid pipes of the indoor unit, and a compressor, characterized in that: Also includes: A first multi-way reversing valve, a second multi-way reversing valve and a third multi-way reversing valve are arranged in parallel, the first multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the air pipe of the indoor unit, the second multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the outdoor heat exchanger, and the third multi-way reversing valve is respectively connected to the exhaust port of the compressor, the air intake port of the compressor and the heat storage module.

2. The outdoor unit according to claim 1, characterized in that: The first multi-way reversing valve, the second multi-way reversing valve and the third multi-way reversing valve are four-way reversing valves.

3. The outdoor unit according to claim 1, characterized in that: It also includes a subcooler, which is provided with a first branch and a second branch, the first end of the first branch is connected to the indoor unit liquid pipe, the second end of the first branch is respectively connected to the heat storage module and the outdoor heat exchanger, the first end of the second branch is connected in series with a subcooling throttle valve and the second end of the first branch, and the second end of the second branch is connected in series with a subcooling control valve and the suction port of the compressor.

4. The outdoor unit according to claim 3, characterized in that: The compressor is also provided with an enthalpy increase port, and the outdoor unit also includes an enthalpy increase branch, the first end of the enthalpy increase branch is connected between the second end of the second branch and the subcooling control valve, and the second end of the enthalpy increase branch is connected to the enthalpy increase port of the compressor.

5. The outdoor unit according to claim 4, characterized in that: The enthalpy increase branch is provided with a muffler.

6. The outdoor unit according to claim 3, characterized in that: A heat storage throttle valve is arranged between the heat storage module and the supercooler.

7. The outdoor unit according to claim 3, characterized in that: A heating throttle valve is arranged between the outdoor heat exchanger and the supercooler.

8. The outdoor unit according to claim 1, characterized in that: The exhaust port of the compressor is connected to an oil separator, and the refrigerant delivered from the exhaust port of the compressor passes through the oil separator.

9. The outdoor unit according to claim 1, wherein: The air intake port of the compressor is connected to a gas-liquid separator, and all refrigerants sent to the air intake port of the compressor pass through the gas-liquid separator.

10. An air conditioning system, characterized in that It comprises an outdoor unit and an indoor unit as described in any one of claims 1 to 9, wherein the indoor unit is connected to the outdoor unit via an air pipe and a liquid pipe.

Images