Multi-connected variable-temperature air conditioning system

Abstract

The utility model belongs to the technical field of air conditioning, and particularly discloses a multi-connected variable-temperature air conditioning system which comprises an outdoor unit part and an indoor unit part which are connected through a connecting pipe, and further comprises more than two room tail end heat exchangers connected with the indoor unit part in parallel, and an indoor sub-control valve module is arranged between each room tail end heat exchanger and the indoor unit part. The air outlet temperature adjusting device is simple in structure and easy to achieve, the multiple branch control valves are correspondingly matched with the multiple tail end heat exchangers connected with the main machine, the air outlet temperatures of different tail ends are independently adjusted, and therefore the different requirements for the temperatures of multiple rooms corresponding to one main machine are met.

Description

Technical Field

[0001] This utility model belongs to the field of air conditioning technology, and specifically discloses a multi-split variable temperature air conditioning system. Background Technology

[0002] An air conditioner is a device used to regulate indoor air temperature and humidity. It can lower indoor temperature in summer and raise indoor temperature in winter, while also removing indoor moisture or increasing humidity to meet people's comfort needs.

[0003] An air conditioner typically consists of a refrigeration system, an air circulation system, and a control system. The refrigeration system is the core of the air conditioner, including components such as a compressor, condenser, expansion valve, and evaporator, used to achieve cooling and heat exchange functions. The air circulation system includes components such as a fan and air filter, used to draw air into the air conditioning system, process it, and then expel it. The control system includes a temperature controller and other control elements, used to regulate indoor temperature and humidity, and to control the operation of the air conditioning equipment.

[0004] Currently, common air conditioners mainly include wall-mounted air conditioners, floor-standing air conditioners, portable air conditioners, and central air conditioning. Different types of air conditioners also differ in terms of power, energy efficiency ratio, and usage scenarios. When choosing an air conditioner, you need to select one based on your own needs and actual situation.

[0005] Among various types of air conditioners, compared to wall-mounted and floor-standing units, central air conditioning does not affect room decoration and does not take up space, making it widely used in offices and large apartments. Existing central air conditioning systems consist of a chiller, cooling water circulation system, chilled water circulation system, fan coil unit system, and cooling tower. During operation, a single main unit connects to multiple terminal air outlets via ducts or hot / cold water pipes, delivering cool or warm air to different areas to regulate the temperature of multiple rooms. While existing central air conditioning systems are one-to-many and facilitate simultaneous temperature control over large areas, the temperature of each terminal air outlet is usually controlled by the main unit. This means that the temperature of each terminal air outlet cannot be adjusted independently, and it cannot meet the temperature requirements of different areas.

[0006] Therefore, there is an urgent need in this field to propose a multi-split variable temperature air conditioning system to address the shortcomings of existing technologies. Utility Model Content

[0007] The purpose of this invention is to propose a multi-split variable temperature air conditioning system with a simple structure and easy implementation. By connecting multiple control valves to multiple terminal heat exchangers connected to the same main unit, the individual temperature adjustment of the air outlet at different terminals can be achieved, thereby meeting the different temperature requirements of multiple rooms corresponding to one main unit.

[0008] The technical solution adopted to achieve the purpose of this utility model is:

[0009] A multi-split variable temperature air conditioning system includes an outdoor unit and an indoor unit, which are connected by a connecting pipe. It also includes two or more room terminal heat exchangers connected in parallel with the indoor unit, and each room terminal heat exchanger is equipped with an indoor control valve module between itself and the indoor unit.

[0010] Furthermore, the outdoor unit includes a compressor, a four-way valve, and an outdoor heat exchanger; the indoor unit includes an indoor heat exchanger and an indoor reheat condenser; wherein, the input end of the four-way valve is connected to the exhaust port of the compressor, the output end I of the four-way valve is connected to one end of the outdoor heat exchanger, the output end II is connected to the suction port of the compressor, and the output end III is connected to one end of the indoor heat exchanger; the two ends of the indoor reheat condenser are respectively connected to the other end of the outdoor heat exchanger and the other end of the indoor heat exchanger, and the end of the indoor reheat condenser connected to the indoor heat exchanger is also connected to the outdoor heat exchanger.

[0011] Furthermore, the indoor control valve module includes connection terminal I, connection terminal II, connection terminal III, and connection terminal IV; wherein, connection terminal I is connected to the pipe located between the outdoor heat exchanger and the indoor reheat condenser; connection terminal II is connected to both ends of the indoor heat exchanger; and connection terminals III and IV are respectively connected to both ends of the room terminal heat exchanger.

[0012] Furthermore, in the indoor control valve module, connection end I and connection end II are connected, and two pipelines are connected in parallel between connection end I and connection end II. One pipeline has control electric valve I and control electric valve II connected in series along the direction from connection end I to connection end II, and the other pipeline has control electric valve IV and control electric valve III connected in series along the direction from connection end I to connection end II.

[0013] Connection terminal III is connected to the pipeline located between the individual control electric valve IV and the individual control electric valve III;

[0014] Furthermore, it also includes a separately controlled expansion valve, one end of which is connected to connection terminal IV, and the other end is connected to the pipeline located between separately controlled electric valve I and separately controlled electric valve II.

[0015] Furthermore, a heating expansion valve and a reheat electric valve are installed on the pipe between the outdoor heat exchanger and the indoor reheat condenser. The heating expansion valve is located at the end closer to the outdoor heat exchanger, and the reheat electric valve is located at the end closer to the indoor reheat condenser. A connecting pipe is also connected in parallel at both ends of the heating expansion valve, and a refrigeration pressure regulating electric valve and a one-way valve I are connected in series along the direction from the outdoor heat exchanger to the indoor reheat condenser.

[0016] Furthermore, a one-way valve II and a refrigeration expansion valve are sequentially installed on the pipe along the direction from the indoor reheat condenser to the indoor heat exchanger.

[0017] It also includes a one-way valve III, one end of which is connected to the connecting pipe located between the four-way valve and the indoor heat exchanger, and the other end is connected to the connecting end II.

[0018] It also includes a refrigeration liquid inlet electric valve, one end of which is connected to a pipe located between the one-way valve II and the refrigeration expansion valve, and the other end is connected to a pipe located between the heating expansion valve and the reheat electric valve.

[0019] It also includes a terminal return gas electric valve, one end of which is connected to the pipe between the one-way valve III and the connection end II, and the other end is connected to the pipe between the refrigeration expansion valve and the indoor heat exchanger.

[0020] Furthermore, a refrigeration pressure regulating expansion valve is connected in parallel at both ends of the terminal return gas electric valve.

[0021] The advantages of this utility model are: it has a simple structure and is easy to implement. By connecting multiple control valves to multiple terminal heat exchangers connected to the same main unit, it enables individual adjustment of the outlet air temperature at different terminals, thereby meeting the different temperature requirements of multiple rooms corresponding to one main unit. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the utility model will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall connection relationship of the system of this utility model.

[0024] Figure 2 This is a partially enlarged schematic diagram of the indoor control valve module in this utility model.

[0025] Figure 3 This is a schematic diagram of the refrigerant flow direction in Embodiment 1 of this utility model.

[0026] Figure 4 This is a schematic diagram of the refrigerant flow direction in Embodiment 2 of this utility model.

[0027] Figure 5 This is a schematic diagram of the refrigerant flow direction in Embodiment 3 of this utility model.

[0028] Figure 6 This is a schematic diagram of the refrigerant flow direction in Embodiment 4 of this utility model.

[0029] In the diagram: 1. Room terminal heat exchanger; 2. Indoor control valve module; 3. Compressor; 4. Four-way valve; 5. Outdoor heat exchanger; 6. Indoor heat exchanger; 7. Indoor reheat condenser; 8. Exhaust port; 9. Suction port; 10. Controlled electric valve I; 11. Controlled electric valve II; 12. Controlled electric valve IV; 13. Controlled electric valve III; 14. Controlled expansion valve; 15. Heating expansion valve; 16. Reheat electric valve; 17. Refrigeration pressure regulating electric valve; 18. Check valve I; 19. Check valve II; 20. Check valve III; 21. Refrigeration expansion valve; 22. Refrigeration liquid inlet electric valve; 23. Terminal return gas electric valve; 24. Refrigeration pressure regulating expansion valve; 25. Outdoor unit; 26. Indoor unit; 27. Water-refrigerant heat exchanger;

[0030] 201. Connecting end I; 202. Connecting end II; 203. Connecting end III; 204. Connecting end IV;

[0031] 401. Input terminal; 402. Output terminal I; 403. Output terminal II; 404. Output terminal III. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, a clear and complete description will be provided below in conjunction with the technical solutions in the embodiments of this utility model. Obviously, the described embodiments are some, but not all, embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0033] like Figures 1 to 6 As shown, a multi-split variable temperature air conditioning system includes an outdoor unit 25 and an indoor unit 26, which are connected by a connecting pipe. It also includes two or more room terminal heat exchangers 1 connected in parallel with the indoor unit 26, and each room terminal heat exchanger 1 is provided with an indoor control valve module 2 between it and the indoor unit 26.

[0034] In this invention, the outdoor unit 25 primarily functions to compress the refrigerant and perform heat exchange, while the indoor unit 26 primarily functions to exchange heat. The multi-split variable temperature air conditioning system of this invention can refer to the design of existing central air conditioning systems. Specifically, in this invention, fresh outdoor air is introduced into the indoor unit. After initial heat exchange by the indoor unit, the fresh air is then delivered to the air inlet of each room's terminal heat exchanger 1 via an air distribution box. Each room's terminal heat exchanger 1 then exchanges heat with the fresh air, thereby achieving further temperature regulation of the fresh air in each room based on the heat exchange by the indoor unit. The indoor control valve module 2 controls the flow and direction of the refrigerant, thereby regulating the indoor temperature corresponding to each room's terminal heat exchanger 1. The number of room terminal heat exchangers 1 and indoor control valve modules 2 can be adjusted according to the specific apartment layout.

[0035] like Figure 1 , Figures 3 to 4 As shown, the outdoor unit 25 includes a compressor 3, a four-way valve 4, and an outdoor heat exchanger 5; the indoor unit 26 includes an indoor heat exchanger 6 and an indoor reheat condenser 7; wherein, the input end 401 of the four-way valve 4 is connected to the exhaust port 8 of the compressor 3, the output end I 402 of the four-way valve 4 is connected to one end of the outdoor heat exchanger 5, the output end II 403 is connected to the suction port 9 of the compressor 3, and the output end III 404 is connected to one end of the indoor heat exchanger 6; the two ends of the indoor reheat condenser 7 are connected to the other end of the outdoor heat exchanger 5 and the other end of the indoor heat exchanger 6, respectively, and the end of the indoor reheat condenser 7 connected to the indoor heat exchanger 6 is also connected to the outdoor heat exchanger 5.

[0036] In this invention, the compressor 3, four-way valve 4, outdoor heat exchanger 5, indoor heat exchanger 6, and indoor reheat condenser 7 are all common devices in the prior art. The compressor 3 functions to upgrade the low-temperature, low-pressure refrigerant gas to a high-temperature, high-pressure refrigerant gas, providing power for the cooling or heating cycle. The four-way valve 4 can switch between cooling and heating by changing the flow direction of the refrigerant in the system piping. The outdoor heat exchanger 5, indoor heat exchanger 6, and indoor reheat condenser 7 function to transfer heat from the hot fluid to the cold fluid, thus performing heat exchange. The connecting pipe is mainly used to transport the refrigerant and can be made of copper.

[0037] like Figure 1 , Figure 2 , Figure 4 and Figure 6 As shown, the indoor control valve module 2 includes connection terminal I 201, connection terminal II 202, connection terminal III 203 and connection terminal IV 204; wherein, connection terminal I 201 is connected to the pipe located between the outdoor heat exchanger 5 and the indoor reheat condenser 7; connection terminal II 202 is connected to both ends of the indoor heat exchanger 6; connection terminal III 203 and connection terminal IV 204 are respectively connected to both ends of the room terminal heat exchanger 1.

[0038] In the indoor control valve module 2, connection end I 201 and connection end II 202 are connected, and two pipelines are connected in parallel between connection end I 201 and connection end II 202. One pipeline has control electric valve I 10 and control electric valve II 11 connected in series along the direction from connection end I 201 to connection end II 202, and the other pipeline has control electric valve IV 13 and control electric valve III 12 connected in series along the direction from connection end I 201 to connection end II 202.

[0039] Connection terminal Ⅲ203 is connected to the pipeline located between the sub-control electric valve Ⅳ13 and the sub-control electric valve Ⅲ12;

[0040] It also includes a sub-controlled expansion valve 14, one end of which is connected to the connection terminal IV204, and the other end is connected to the pipeline located between the sub-controlled electric valve I10 and the sub-controlled electric valve II11.

[0041] The indoor control valve module 2 of this utility model adopts the above design and can arbitrarily adjust the on / off state of the control electric valve, thereby realizing the conversion between the liquid inlet port and the liquid outlet port of the refrigerant in the indoor control valve module 2, and further realizing the independent adjustment of the indoor temperature corresponding to each room terminal heat exchanger 1 in either cooling or heating mode.

[0042] like Figure 1 , Figures 3 to 6 As shown, a heating expansion valve 15 and a reheat electric valve 16 are also provided on the pipe between the outdoor heat exchanger 5 and the indoor reheat condenser 7. The heating expansion valve 15 is located at the end closer to the outdoor heat exchanger 5, and the reheat electric valve 16 is located at the end closer to the indoor reheat condenser 7. A connecting pipe is also connected in parallel at both ends of the heating expansion valve 15, and a refrigeration pressure regulating electric valve 17 and a one-way valve I 18 are connected in series along the direction from the outdoor heat exchanger 5 to the indoor reheat condenser 7.

[0043] The refrigeration pressure regulating electric valve 17 mainly regulates the pressure and flow rate of the refrigerant, while the one-way valve I 18 controls the unidirectional flow of the refrigerant. In this invention, the one-way valve I 18 controls the refrigerant to flow only in one direction from the outdoor heat exchanger 5 to the indoor heat exchanger 6, and the refrigeration pressure regulating electric valve 17 and the one-way valve I 18 are only used during the refrigeration process. The heating expansion valve 15 serves to throttle and reduce pressure and regulate flow rate, and it can be used in both refrigeration and heating processes.

[0044] like Figures 1 to 6 As shown, a one-way valve II 19 and a refrigeration expansion valve 21 are also installed sequentially on the pipe along the direction from the indoor reheat condenser 7 to the indoor heat exchanger 6.

[0045] It also includes a one-way valve Ⅲ20, one end of which is connected to the connecting pipe located between the four-way valve 4 and the indoor heat exchanger 6, and the other end is connected to the connecting end Ⅱ202;

[0046] It also includes a refrigeration liquid inlet electric valve 22, one end of which is connected to a pipe located between the one-way valve II 19 and the refrigeration expansion valve 21, and the other end is connected to a pipe located between the heating expansion valve 15 and the reheat electric valve 16.

[0047] It also includes a terminal return gas electric valve 23, one end of which is connected to the pipe between the one-way valve Ⅲ 20 and the connecting end Ⅱ 202, and the other end is connected to the pipe between the refrigeration expansion valve 21 and the indoor heat exchanger 6.

[0048] One-way valve II 19 controls the unidirectional flow of refrigerant, specifically, it controls the unidirectional flow of refrigerant along the pipe between the indoor reheat condenser 7 and the refrigeration expansion valve 21 and the refrigerant inlet electric valve 22. One-way valve III 20 is used only during heating, controlling the unidirectional flow of refrigerant along the four-way valve 4 towards the indoor sub-control module. The functions of the refrigerant inlet electric valve 22 and the terminal return electric valve 23 can both open or close different valves as needed, thereby controlling the flow of refrigerant. In actual use, the refrigerant inlet electric valve 22 can be used during either cooling or heating, while the terminal return electric valve 23 is only used during cooling.

[0049] like Figure 1 , Figure 4 and Figure 6 As shown, a refrigerant pressure regulating expansion valve 24 is connected in parallel at both ends of the terminal return gas electric valve 23. The purpose of the refrigerant pressure regulating expansion valve 24 is to cooperate with the terminal return gas electric valve 23 to control the refrigerant pressure and flow. The refrigerant pressure regulating expansion valve 24 cooperates with the corresponding sub-control pressure regulating electric valve of each room terminal heat exchanger 1 to further control the refrigerant flow in each indoor sub-control module, thereby realizing independent adjustment of the room temperature corresponding to different room terminal heat exchangers 1.

[0050] The following examples illustrate specific application scenarios of this invention, with reference to the refrigerant flow direction. Figures 3 to 6 In the diagram, solid arrows represent the direction of refrigerant flow. To facilitate observation of the refrigerant flow direction, valves and components not used in the diagram have been omitted.

[0051] Example 1

[0052] like Figure 3 As shown, this embodiment only implements the "cooling mode".

[0053] Refrigeration Process: In refrigeration mode, the four-way valve 4 connects the compressor 3's exhaust port 8 to the outdoor heat exchanger 5. The compressor 3 compresses the refrigerant into a high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas undergoes heat exchange and dissipation through the outdoor heat exchanger 5. Simultaneously, outdoor air drawn into the outdoor heat exchanger 5 by its axial fan flows through the outdoor heat exchanger 5, carrying away the heat released by the refrigerant. This causes the high-temperature, high-pressure refrigerant vapor to condense into a medium-temperature, high-pressure liquid refrigerant. At this point, the outdoor heat exchanger 5 acts as a condenser. The medium-temperature, high-pressure liquid refrigerant flows out of the outdoor condenser in the following direction during the refrigeration process: refrigerant pressure regulating electric valve → one-way valve I18 → refrigerant liquid inlet electric valve 22 → refrigerant expansion valve 21 → indoor heat exchanger 6. In the indoor heat exchanger 6, it absorbs heat from its surroundings and evaporates into a gaseous refrigerant. Simultaneously, the cross-flow fan of the indoor heat exchanger 6 continuously draws air into the fins of the indoor heat exchanger 6 for heat exchange, and sends the cooled air into the room. At this time, the indoor heat exchanger 6 acts as an evaporator. Then, the gaseous refrigerant flows out of the indoor heat exchanger 6 and returns to the compressor 3 through the suction port 9 to begin the next cycle. Through this process, cooling can be achieved in the indoor unit, and the cooled air can then be distributed to each room through the air distribution box. In implementing this embodiment, to avoid refrigerant flow disorder, unused valves should be closed.

[0054] Example 2

[0055] like Figure 4 As shown, this embodiment mainly aims to achieve "independent temperature control for different rooms in cooling + dehumidification mode".

[0056] Refrigeration + Dehumidification Process: In refrigeration + dehumidification mode, the four-way valve 4 connects the compressor 3's exhaust port 8 to the outdoor heat exchanger 5. The compressor 3 compresses the refrigerant into a high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas undergoes heat exchange and dissipation through the outdoor heat exchanger 5. Simultaneously, outdoor air drawn into the outdoor heat exchanger 5 by its axial fan flows through the outdoor heat exchanger 5, carrying away the heat released by the refrigerant. This causes the high-temperature, high-pressure refrigerant vapor to condense into a medium-temperature, high-pressure liquid refrigerant. At this point, the outdoor heat exchanger 5 acts as a condenser. The flow direction of the medium-temperature, high-pressure liquid refrigerant after exiting the outdoor condenser in the refrigeration process is as follows: refrigerant pressure regulating electric valve → one-way valve I 18 → reheat electric valve 16 → indoor reheat condenser 7 → one-way valve II 19 → refrigeration expansion valve 21 → indoor heat exchanger 6. In this process, the refrigerant absorbs heat from the surrounding air in the indoor reheat condenser 7 and evaporates into a high-temperature gaseous refrigerant. Then, in the indoor heat exchanger 6, the refrigerant releases heat to the surrounding air and becomes a low-temperature gaseous refrigerant. In actual installation, the air outlet of the indoor reheat condenser 7 can be aligned with the air inlet of the indoor heat exchanger 6. After the indoor fan draws in air, it first passes through the reheat condenser for cooling, and then through the indoor heat exchanger 6 for heating. During the cooling and dehumidification process, cooling the air first liquefies the gaseous water in the air, forming dry, cold air, which is then discharged through corresponding pipes. The dry, cold air is heated after passing through the indoor heat exchanger 6, ensuring that the air blown into the room is not too cold while still achieving dehumidification. The degree of dehumidification can be adjusted by regulating the opening and closing of the reheat solenoid valve and the refrigeration expansion valve 21. The two valves working together can also achieve constant-temperature dehumidification. After flowing out of the indoor heat exchanger 6, the gaseous refrigerant returns to the compressor 3 through the suction port 9 to begin the next cycle. Through the above process, air cooling and dehumidification can be achieved in the indoor unit. When implementing this embodiment, to avoid disrupting the refrigerant flow, all unused valves should be closed.

[0057] like Figure 4 As shown, in this embodiment, taking three room terminal heat exchangers 1 as an example, the first and third room terminal heat exchangers 1 from left to right are in cooling mode and are cooling again; the second room terminal heat exchanger 1 is in cooling mode and is heating up. The specific temperature adjustment process of each heat exchanger is as follows:

[0058] The first and third independent temperature control processes: Based on the above-mentioned refrigeration and dehumidification processes, the refrigerant is split after flowing out of one-way valve I18. One part flows to the refrigerant inlet electric valve 22, and the other part flows to the indoor control valve module 2. In the indoor control valve module 2, the control electric valves II11 and IV13 are opened. After the refrigerant branches out from one-way valve I18, the flow sequence of the refrigerant in the direction of the indoor control valve module 2 is as follows: one-way valve I18 → connection end I201 → control electric valve IV13 → connection end III203 → room terminal heat exchanger 1 → connection end IV204 → control expansion valve 14 → control electric valve II11 → connection end II202 → terminal return gas electric valve 23 → indoor heat exchanger 6. Then, the refrigerant returning from the indoor control valve module 2 merges with the gaseous refrigerant in the indoor heat exchanger 6 and flows out of the indoor heat exchanger 6, and returns to the compressor 3 through the suction port 9 of the compressor 3 to enter the next cycle. During this process, the flow and pressure of refrigerant in the room terminal heat exchanger 1 can be controlled by the refrigeration pressure regulating expansion valve 24 and the separate control expansion valve 14, thereby achieving the re-cooling of the room terminal temperature. Each room terminal heat exchanger 1 can be independently adjusted.

[0059] The second independent temperature control process: Based on the above refrigeration and dehumidification process, the refrigerant is split after flowing out of the one-way valve I18. One part flows to the refrigerant inlet electric valve 22, and the other part flows to the indoor control valve module 2. In the indoor control valve module 2, the control electric valves I10 and III12 are opened. After the refrigerant branches out from the one-way valve I18, the flow sequence of the refrigerant in the direction of the indoor control valve module 2 is as follows: one-way valve I18 → connection end I201 → control electric valve I10 → control expansion valve 14 → room terminal heat exchanger 1 → connection end III203 → room terminal heat exchanger III12 → connection end II202 → terminal return gas electric valve 23 → indoor heat exchanger 6. Then, the refrigerant returning from the indoor control valve module 2 merges with the gaseous refrigerant in the indoor heat exchanger 6 and flows out of the indoor heat exchanger 6, and returns to the compressor 3 through the suction port 9 of the compressor 3 to enter the next cycle. During this process, the flow and pressure of refrigerant in the room terminal heat exchanger 1 can be controlled by the refrigeration pressure regulating expansion valve 24 and the separate control expansion valve 14, thereby achieving reheating of the room terminal temperature. Each room terminal heat exchanger 1 can be independently adjusted.

[0060] The solution in this embodiment is mainly applied in spring and autumn. After the air is initially cooled and dehumidified in the indoor unit 26, if each room needs further cooling or heating, the temperature can be readjusted through the indoor control module.

[0061] Example 3

[0062] like Figure 5 As shown, this embodiment only implements the "heating mode".

[0063] Heating Process: In heating mode, the four-way valve 4 connects the compressor 3's exhaust port 8 to the indoor heat exchanger 6. The compressor 3 compresses the refrigerant into a high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas undergoes heat exchange and dissipation through the indoor heat exchanger 6. Simultaneously, the cross-flow fan of the indoor heat exchanger 6 continuously draws air into the fins of the indoor heat exchanger for heat exchange, and sends the heated air back into the room, causing the high-temperature, high-pressure refrigerant vapor to condense into a medium-temperature, high-pressure liquid. At this time, the indoor heat exchanger 6 acts as a condenser. The medium-temperature, high-pressure liquid refrigerant flows from the indoor heat exchanger 6 in the following direction during the cooling process: refrigeration expansion valve 21 → refrigeration liquid inlet electric valve 22 → heating expansion valve 15 → outdoor heat exchanger 5. In the outdoor heat exchanger 5, it absorbs heat from its surroundings and evaporates into a gaseous refrigerant. Simultaneously, the cross-flow fan of the outdoor heat exchanger 5 continuously draws air into the fins of the outdoor heat exchanger 5 for heat exchange. At this time, the indoor heat exchanger 6 acts as an evaporator. Then, the gaseous refrigerant flows out of the outdoor heat exchanger 5 and returns to the compressor 3 through the suction port 9 to begin the next cycle. Through this process, heating can be achieved in the indoor unit, and the heated air is then distributed to each room via the air distribution box. In implementing this embodiment, to avoid disrupting the refrigerant flow, any unused valves should be closed.

[0064] Example 4

[0065] like Figure 6 As shown, this embodiment mainly aims to achieve "independent temperature control of different rooms in heating mode".

[0066] Heating Process: The basic heating mode in this embodiment is the same as that in Embodiment 3. In heating mode, the four-way valve 4 connects the compressor 3 exhaust port 8 to the indoor heat exchanger 6. The compressor 3 compresses the refrigerant into a high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas undergoes heat exchange and dissipation through the indoor heat exchanger 6. Simultaneously, the cross-flow fan of the indoor heat exchanger 6 continuously draws air into the fins of the indoor heat exchanger for heat exchange, and sends the heated air back into the room. The high-temperature, high-pressure refrigerant vapor condenses into a medium-temperature, high-pressure liquid. At this time, the indoor heat exchanger 6 acts as a condenser. The medium-temperature, high-pressure liquid refrigerant flows from the indoor heat exchanger 6 in the following direction during the cooling process: refrigeration expansion valve 21 → refrigeration liquid inlet electric valve 22 → heating expansion valve 15 → outdoor heat exchanger 5. In the outdoor heat exchanger 5, it absorbs heat from its surroundings and evaporates into a gaseous refrigerant. Meanwhile, the cross-flow fan of the outdoor heat exchanger 5 continuously draws air into the fins of the outdoor heat exchanger 5 for heat exchange. At this time, the indoor heat exchanger 6 acts as an evaporator. Then, the gaseous refrigerant flows out of the outdoor heat exchanger 5 and returns to the compressor 3 through the suction port 9 to begin the next cycle. Through the above process, air heating can be achieved in the indoor unit. In implementing this embodiment, to avoid refrigerant flow disorder, unused valves should be closed.

[0067] Independent temperature control process: Based on the above heating process, open the one-way valve Ⅲ20. The refrigerant flows out from the four-way valve 4 and branches, with part flowing to the indoor heat exchanger 6 and part flowing to the one-way valve Ⅲ20. After the refrigerant flows out of the one-way valve Ⅲ20, the flow sequence of the refrigerant in the direction of the indoor control valve module 2 is as follows: one-way valve Ⅲ20 → connection end Ⅱ202 → control electric valve Ⅲ12 → connection end Ⅲ203 → room terminal heat exchanger 1 → connection end Ⅳ204 → control expansion valve 14 → control electric valve Ⅰ10 → connection end Ⅰ201 → heating expansion valve 15 → outdoor heat exchanger 5.

[0068] Then, the refrigerant returning from the indoor control valve module 2 merges with the gaseous refrigerant in the outdoor heat exchanger 5 and flows out of the outdoor heat exchanger 5, then returns to the compressor 3 through the suction port 9 to enter the next cycle. During this process, the flow rate and pressure of the refrigerant in the room terminal heat exchanger 1 can be controlled by the refrigeration pressure regulating expansion valve 24 and the control pressure regulating valve, thereby achieving independent adjustment of the room terminal temperature.

[0069] The solution in this embodiment is mainly applied in winter. After the air is initially heated by the indoor unit 26, if each room needs further heating, the temperature can be readjusted through the indoor control module.

[0070] In this utility model, the room terminal heat exchanger 1 can be an air-cooled heat exchanger or a water-fluorine heat exchanger 27, specifically as follows: Figure 1 , Figure 4 and Figure 6 As shown. Both the air-cooled heat exchanger and the water-fluorine heat exchanger 27 are common heat exchangers in the prior art, such as the heat exchanger disclosed in patent publication number CN217559952U. The room terminal heat exchanger 1 can be wall-mounted or ceiling-mounted.

[0071] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific implementation method of this utility model and is not intended to limit this utility model. Any modifications, equivalent substitutions, and improvements made within the scope of the spirit of this utility model should be included within the protection scope of this utility model.

Claims

1. A multi-split variable temperature air conditioning system, comprising an outdoor unit (25) and an indoor unit (26), wherein the outdoor unit (25) and the indoor unit (26) are connected by a connecting pipe, characterized in that, It also includes two or more room terminal heat exchangers (1) connected in parallel with the indoor unit (26), and each room terminal heat exchanger (1) is also provided with an indoor control valve module (2) between it and the indoor unit (26).

2. The multi-split variable temperature air conditioning system according to claim 1, characterized in that, The outdoor unit (25) includes a compressor (3), a four-way valve (4), and an outdoor heat exchanger (5); the indoor unit (26) includes an indoor heat exchanger (6) and an indoor reheat condenser (7); wherein, the input end (401) of the four-way valve (4) is connected to the exhaust port (8) of the compressor (3), the output end I (402) of the four-way valve (4) is connected to one end of the outdoor heat exchanger (5), the output end II (403) is connected to the suction port (9) of the compressor (3), and the output end III (404) is connected to one end of the indoor heat exchanger (6); the two ends of the indoor reheat condenser (7) are connected to the other end of the outdoor heat exchanger (5) and the other end of the indoor heat exchanger (6), respectively, and the end of the indoor reheat condenser (7) connected to the indoor heat exchanger (6) is also connected to the outdoor heat exchanger (5).

3. The multi-split variable temperature air conditioning system according to claim 2, characterized in that, The indoor control valve module (2) includes connection end I (201), connection end II (202), connection end III (203) and connection end IV (204); wherein, connection end I (201) is connected to the pipe located between the outdoor heat exchanger (5) and the indoor reheat condenser (7); connection end II (202) is connected to both ends of the indoor heat exchanger (6); connection end III (203) and connection end IV (204) are respectively connected to both ends of the room terminal heat exchanger (1).

4. The multi-split variable temperature air conditioning system according to claim 3, characterized in that, In the indoor control valve module (2), connection end I (201) and connection end II (202) are connected, and two pipelines are connected in parallel between connection end I (201) and connection end II (202). One pipeline is connected in series with control electric valve I (10) and control electric valve II (11) along the direction from connection end I (201) to connection end II (202). The other pipeline is connected in series with control electric valve IV (13) and control electric valve III (12) along the direction from connection end I (201) to connection end II (202). Connection terminal Ⅲ (203) is connected to the pipeline located between the sub-control electric valve Ⅳ (13) and the sub-control electric valve Ⅲ (12).

5. The multi-split variable temperature air conditioning system according to claim 4, characterized in that, It also includes a sub-control expansion valve (14), one end of which is connected to the connection end IV (204), and the other end is connected to the pipeline located between the sub-control electric valve I (10) and the sub-control electric valve II (11).

6. The multi-split variable temperature air conditioning system according to claim 2, 3, 4 or 5, characterized in that, A heating expansion valve (15) and a reheat electric valve (16) are also provided on the pipe between the outdoor heat exchanger (5) and the indoor reheat condenser (7). The heating expansion valve (15) is located at the end closer to the outdoor heat exchanger (5), and the reheat electric valve (16) is located at the end closer to the indoor reheat condenser (7). A connecting pipe is also connected in parallel at both ends of the heating expansion valve (15), and a refrigeration pressure regulating electric valve (17) and a one-way valve I (18) are connected in series along the direction from the outdoor heat exchanger (5) to the indoor reheat condenser (7).

7. The multi-split variable temperature air conditioning system according to claim 6, characterized in that, A one-way valve II (19) and a refrigeration expansion valve (21) are also installed in sequence on the pipe from the indoor reheat condenser (7) to the indoor heat exchanger (6); It also includes a one-way valve III (20), one end of which is connected to the connecting pipe between the four-way valve (4) and the indoor heat exchanger (6), and the other end is connected to the connecting end II (202); It also includes a refrigeration liquid inlet electric valve (22), one end of which is connected to a pipe between the one-way valve II (19) and the refrigeration expansion valve (21), and the other end is connected to a pipe between the heating expansion valve (15) and the reheat electric valve (16). It also includes a terminal return gas electric valve (23), one end of which is connected to a pipe between the one-way valve III (20) and the connecting end II (202), and the other end is connected to a pipe between the refrigeration expansion valve (21) and the indoor heat exchanger (6).

8. The multi-split variable temperature air conditioning system according to claim 7, characterized in that, The end return gas electric valve (23) is also connected in parallel with a refrigeration pressure regulating expansion valve (24).

Images