Air conditioning unit

Abstract

The application discloses an air conditioner unit, which comprises a heat pump circulation loop and a defrosting circulation loop, wherein the heat pump circulation loop is provided with a first branch communicating with an inlet pipeline and an outlet pipeline of an indoor unit, the first branch is provided with a heat storage module and a heat storage throttling device, the air conditioner unit further comprises a second branch, one end of the second branch communicates with the inlet of the indoor unit, the other end of the second branch communicates with a suction port of a defrosting compressor, and a second control valve is arranged on the second branch; and a third branch, one end of the third branch communicates with a second end of a fourth pipeline of an outdoor heat exchanger, the other end of the third branch communicates with a first end of a third pipeline of the outdoor heat exchanger, and a third control valve is arranged on the third branch. The application can not only continuously supply heat to the indoor unit during heating to ensure the comfort, but also can improve the refrigeration efficiency of the whole machine when the defrosting circulation loop participates in the refrigeration operation during the indoor cooling.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of air conditioning technology, and in particular to a dual-system heat pump air conditioning unit. BACKGROUND

[0002] The existing heat pump air conditioning system unit is generally composed of a compressor, a four-way valve, a condenser, a throttling device, an evaporator and other functional components. The cooling or heating function of the air conditioner is realized by switching the four-way valve. When the air conditioning system operates in the heating mode, low-temperature refrigerant needs to absorb heat from the outdoor heat exchanger to vaporize. When the outdoor environment temperature is relatively low, the outdoor heat exchanger will frost, and as the thickness of the frost layer gradually increases, it will seriously affect the heat exchange effect of the outdoor heat exchanger, resulting in a rapid decline in indoor heating efficiency. At this time, defrosting of the outdoor heat exchanger is required. The defrosting method of the conventional air conditioner is to stop the indoor and outdoor fans when the defrosting condition is met, reverse the four-way valve, and flow the high-temperature and high-pressure refrigerant discharged by the compressor into the outdoor heat exchanger to release heat and melt the frost layer on the surface of the outdoor heat exchanger. During the defrosting operation, the indoor unit stops heating and switches to cooling, resulting in a significant drop in indoor temperature and affecting comfort.

[0003] To solve the contradiction between defrosting and comfort, one solution is to introduce a defrosting circulation loop and a heat storage module connecting the heat pump circulation loop and the defrosting circulation loop. When the air conditioning system operates in the heating mode, part of the high-temperature refrigerant flows into the heat storage module and releases heat, which is absorbed and stored by the heat storage medium in the heat storage module. When the outdoor heat exchanger needs to be defrosted, the refrigerant discharged by the defrosting compressor enters the heat storage module after passing through the outdoor heat exchanger and the defrosting throttling device, and vaporizes by absorbing heat from the heat storage medium, and then returns to the defrosting compressor for circulation. Since the heat pump air conditioning circuit and the defrosting circuit share the outdoor heat exchanger, continuous heating to the indoor can be achieved when the outdoor unit is defrosting, improving user comfort. However, this system, when the outdoor heat exchanger does not need to be defrosted, the defrosting circuit is idle, resulting in low utilization of this part of the equipment. SUMMARY

[0004] The present application proposes an air conditioning unit to solve the technical problem of long idle time and low utilization of part of the equipment in the unit with a defrosting circuit in the prior art.

[0005] The technical solution adopted by the present application is to design an air conditioning unit, comprising:

[0006] a heat pump circulation loop, comprising a heat pump compressor, an outdoor heat exchanger and an indoor unit, the outdoor heat exchanger is provided with a third pipeline, the first end of which is in communication with the outlet of the indoor unit in the heating state, and the second end is in communication with the suction port of the heat pump compressor;

[0007] The defrosting circulation loop comprises a defrosting compressor, the outdoor heat exchanger and a heat storage module, the outdoor heat exchanger is provided with a fourth pipeline, a first end of which is communicated with the defrosting compressor exhaust pipe, and a second end of which is communicated with the inlet end of the heat storage module;

[0008] The first branch is communicated at one end with the first end of the third pipeline of the outdoor heat exchanger, and at the other end with the heat pump compressor exhaust pipe, and the first branch is provided with a heat storage module and a heat storage throttling device;

[0009] The air conditioning unit further comprises a second branch communicated at one end with the inlet of the indoor unit in the heating state, and at the other end with the defrosting compressor suction port, and a third branch communicated at one end with the second end of the fourth pipeline of the outdoor heat exchanger, and at the other end with the first end of the third pipeline of the outdoor heat exchanger, and the third branch is provided with a third control valve.

[0010] The heat storage module comprises a heat storage medium, a first pipeline communicated with the heat pump circulation loop and a second pipeline communicated with the defrosting circulation loop.

[0011] Preferably, the heat storage medium is a mixture of graphite and paraffin.

[0012] Preferably, the first pipeline and the second pipeline are staggered.

[0013] Preferably, the third pipeline and the fourth pipeline in the outdoor heat exchanger are staggered.

[0014] In an embodiment, the heat storage module and the heat storage throttling device are integrally arranged and detachably connected with the outdoor unit.

[0015] In another embodiment, the heat storage module and the heat storage throttling device are arranged in the outdoor unit.

[0016] When the defrosting circulation loop participates in the refrigeration cycle, the second control valve on the second branch and the third control valve on the third branch are opened, and the first control valve connected with the heat storage module on the defrosting circulation loop is closed.

[0017] When the defrosting circulation loop defrosts, the second control valve on the second branch and the third control valve on the third branch are closed, and the heat storage throttling device on the first branch, the defrosting throttling device and the first control valve in front of the heat storage module on the defrosting circulation loop are opened.

[0018] In a preferred embodiment, the air conditioning unit provided by the present application comprises:

[0019] The heat pump circulation loop comprises a heat pump compressor, a four-way valve, an outdoor heat exchanger, a throttling device and an indoor unit, the outdoor heat exchanger is provided with a third pipeline, a first end of the third pipeline is communicated with an outlet of the indoor unit in a heating state, and a second end of the third pipeline is communicated with a suction port of the heat pump compressor;

[0020] The defrosting circulation loop comprises a defrosting compressor, the outdoor heat exchanger, a first control valve, a one-way valve, a defrosting throttling device and a heat storage module, the outdoor heat exchanger is provided with a fourth pipeline, a first end of the fourth pipeline is communicated with a discharge pipe of the defrosting compressor, and a second end of the fourth pipeline is communicated with an inlet end of the heat storage module;

[0021] A first branch is communicated at one end with the first end of the third pipeline of the outdoor heat exchanger and at the other end with a discharge pipe of the heat pump compressor, the first branch is provided with a heat storage module and a heat storage throttling device, the heat storage module is provided with a first pipeline and a second pipeline, the first pipeline is communicated with the heat pump circulation loop, and the second pipeline is communicated with the defrosting circulation loop;

[0022] The air conditioning unit further comprises a second branch communicated at one end with an inlet of the indoor unit in the heating state and at the other end with a suction port of the defrosting compressor, and a third branch communicated at one end with the second end of the fourth pipeline of the outdoor heat exchanger and at the other end with the first end of the third pipeline of the outdoor heat exchanger, the third branch is provided with a third control valve and a one-way valve.

[0023] Compared with the prior art, the present application has the following beneficial effects:

[0024] 1. When the air conditioning unit is in a refrigeration operation, the defrosting circulation loop participates in the refrigeration operation, thereby improving the utilization rate of the defrosting loop and the refrigeration efficiency of the unit.

[0025] 2. When the outdoor heat exchanger is defrosted, the heat pump circulation loop does not need to be reversed through the four-way valve to enter the refrigeration mode, and the high-temperature and high-pressure gas of the defrosting circulation loop enters the outdoor heat exchanger to defrost, thereby realizing continuous heating of the air conditioning unit, maintaining the stability of the indoor temperature and improving the air conditioning comfort. BRIEF DESCRIPTION OF DRAWINGS

[0026] The present application will be described in detail below in combination with the drawings and specific embodiments, in which:

[0027] Figure 1 It is a schematic diagram of the heat pump air conditioning system according to the present application, and the arrows show the refrigeration cycle;

[0028] Figure 2 It is a schematic diagram of another embodiment of the present application.

[0029] The components are as follows: 1. Heat pump compressor, 2. Four-way valve, 3. Outdoor heat exchanger, 4. Throttling device, 5. Indoor unit, 6. Shut-off valve, 7. Heat storage module, 8. First branch, 9. Heat storage throttling device, 10. Defrosting throttling pipe, 11. Defrosting compressor suction pipe, 12. Second control valve, 13. Defrosting throttling device, 14. Second branch, 15. Third branch, 16. Defrosting compressor, 19. Third control valve, 20. Check valve, 21. First control valve, 22. Outdoor unit, 51. Indoor unit throttling device, 52. Indoor heat exchanger, 53. Indoor unit fan. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and embodiments. The term "connection" as used herein refers to the ability of two components to communicate, but does not exclude the possibility of other components being provided between the two components. It should be understood that the following specific embodiments are only used to explain this invention and do not constitute a limitation thereof.

[0031] The heat pump air conditioning unit proposed in this invention includes two circulation loops: a heat pump circulation loop and a defrost circulation loop, both of which share an outdoor heat exchanger. The heat pump circulation loop includes a heat pump compressor 1, a four-way valve 2, an outdoor heat exchanger 3, a throttling device 4, and an indoor unit 5. The defrost circulation loop includes a defrost compressor 16, an outdoor heat exchanger 3, a first control valve 21, a one-way valve 20, a defrost throttling device 13, and a heat storage module 7.

[0032] The heat pump circulation loop also includes a first branch 8, which is equipped with a heat storage module. This heat storage module contains a first pipe and a second pipe. The first pipe is connected to the heat pump circulation loop, and the second pipe is connected to the defrost circulation loop. This heat storage module facilitates the transfer of heat energy between the heat pump circulation loop and the defrost circulation loop. Furthermore, two branches controlled by control valves are installed between the heat pump circulation loop and the defrost circulation loop. This allows the low-temperature, low-pressure liquid refrigerant from the defrost circulation loop to flow into the indoor unit for cooling during heat pump circulation loop operation, improving the overall cooling performance.

[0033] like Figure 1As shown, the heat pump air conditioning unit includes an indoor unit 5 and an outdoor unit 22. The heat pump compressor 1, four-way valve 2, outdoor heat exchanger 3, and throttling device 4 are located in the outdoor unit. The indoor unit 5 includes an indoor unit throttling device 51, an indoor heat exchanger 52, and an indoor unit fan 53. The inlet and outlet pipes of the indoor unit are connected to the outdoor unit through a shut-off valve 6. During heating operation, the high-temperature and high-pressure refrigerant discharged from the heat pump compressor 1 is introduced into the indoor unit 5 through the four-way valve 2 and the shut-off valve 6. After releasing heat in the indoor unit, the refrigerant flows sequentially through the indoor unit throttling device 51, the shut-off valve 6, the throttling device 4, the outdoor heat exchanger 3, and the four-way valve 2 before returning to the suction port of the heat pump compressor 1 for recirculation. During cooling operation, the high-temperature, high-pressure refrigerant discharged from the heat pump compressor 1 enters the four-way valve 2 for reversal, then passes through the outdoor heat exchanger 3, the throttling device 4, and the shut-off valve 6 before entering the indoor unit. After passing through the indoor unit's throttling device 51, the refrigerant absorbs heat and vaporizes in the indoor heat exchanger 52. It then returns to the suction port of the heat pump compressor 1 after passing through the shut-off valve 6 and the four-way valve 2, forming a cooling cycle. Both the outdoor heat exchanger 3 and the indoor heat exchanger 52 are equipped with fans to enhance airflow and improve heat exchange efficiency.

[0034] The dual-system heat pump circulation loop proposed in this invention also includes a first branch 8 connected to the indoor unit's inlet pipe and outlet pipe, with the heat storage module 7 and the heat storage throttling device 9 sequentially arranged on the first branch.

[0035] The heat storage module 7 includes a first pipe and a second pipe, adopting a two-inlet, two-outlet structure. The first pipe is connected to the heat pump circulation loop, and the second pipe is connected to the defrost circulation loop. The heat storage module contains a heat storage medium; in this embodiment, the heat storage medium is a mixture of graphite and paraffin. Preferably, the first and second pipes are arranged alternately to make heat exchange more uniform.

[0036] When the heat pump circulation loop is in heating mode, a portion of the high-temperature, high-pressure refrigerant flowing out of the four-way valve 2 is diverted to the first branch 8 and released heat in the heat storage module 7. The released heat is absorbed and stored by the heat storage medium in the heat storage module. After the refrigerant releases heat, it is depressurized through the heat storage throttling device 9 and then flows into the liquid outlet pipe of the indoor unit. When the heat pump circulation loop is in cooling mode, the heat storage throttling device 9 is closed, the first branch is in an open-circuit state, and does not participate in the refrigerant circulation.

[0037] When the unit control logic determines that defrosting is required, the defrosting loop starts the cooling operation mode. The high-temperature and high-pressure refrigerant discharged from the defrosting compressor 16 flows into the outdoor heat exchanger 3 and releases heat there, defrosting the frost layer on the surface of the outdoor heat exchanger fins. The refrigerant after releasing heat then flows through the first control valve 21, the one-way valve 20, and the defrosting throttling device 13 to the heat storage module 7, where it absorbs the heat stored in the heat storage medium and vaporizes. After that, it returns to the suction port of the defrosting compressor 16 for recirculation.

[0038] In the above embodiment, the heat pump circulation loop and the defrost circulation loop share the outdoor heat exchanger 3. The outdoor heat exchanger is a finned heat exchanger with a third pipe and a fourth pipe inside. The third pipe is connected to the heat pump circulation loop, and the fourth pipe is connected to the defrost circulation loop. Both the third and fourth pipes are composed of U-shaped pipes and elbows. The two pipes can be arranged in a concentrated area or staggered, the latter making the outdoor heat exchanger heatd more evenly during defrosting.

[0039] like Figure 1 As shown, the heat pump air conditioning unit proposed in this invention has a second branch 14 and a third branch 15 respectively between the heat pump circulation loop and the defrost circulation loop. One end of the second branch is connected to one end of the first branch 8 (the heat storage module's heat storage inlet pipe), and the other end is connected to the suction pipe 11 of the defrost compressor 16. A second control valve 12 and a one-way valve 20 are sequentially provided on the second branch. One end of the third branch 15 is located at the second end of the fourth pipe of the outdoor heat exchanger, and the other end is located at the first end of the third pipe of the outdoor heat exchanger, that is, on the pipe between the outdoor heat exchanger 3 and the throttling device 4. A third control valve 19 and a one-way valve 20 are provided on the third branch.

[0040] When the heat pump air conditioning unit is in heating mode, the heat pump circulation loop works. The first and second pipes in the heat storage module 7 exchange heat through the heat storage medium. The heat storage medium absorbs and stores the heat energy released by the refrigerant. The heat absorbed by the heat storage medium is absorbed by the low-temperature medium after throttling in the defrost circulation loop, realizing the transfer of heat energy between the heating circulation loop and the defrost circulation loop with the heat storage medium of the heat storage module as the medium.

[0041] The outdoor heat exchanger 3, which is shared by the heat pump circulation loop and the defrost circulation loop, has high-temperature and high-pressure gas discharged from the defrost compressor 16 flowing through the fourth pipe in the outdoor heat exchanger 3 during defrosting. This gas exchanges heat with the low-temperature refrigerant in the heat pump circulation loop in the third pipe, causing the frost layer in the low-temperature zone to melt and achieve the purpose of defrosting the outdoor heat exchanger.

[0042] Therefore, in the dual-system heat pump air conditioning unit with heat storage module proposed in this invention, the operation of the heating cycle loop and the defrosting cycle loop do not interfere with each other and can operate simultaneously. That is, the indoor unit can be heating while the outdoor heat exchanger is defrosting. This eliminates the need to switch to cooling operation mode via a four-way valve to defrost the outdoor heat exchanger when the air conditioner is heating. In other words, the low-temperature refrigerant in the defrosting loop will not flow into the indoor unit, thus achieving continuous heating of the indoor unit and improving the comfort of the indoor air conditioning.

[0043] When the heat pump air conditioning unit operates in cooling mode, the heat pump circulation loop works. The unit control unit controls the second control valve 12 on the second branch and the third control valve 19 on the third branch to open, while the first control valve 21 at the front end of the defrost throttling valve 13 is closed. The high-temperature, high-pressure refrigerant discharged from the defrost compressor 16 releases heat through the outdoor heat exchanger 3 and enters the first end of the third pipe of the outdoor heat exchanger through the third branch 15. Together with the refrigerant in the cooling circulation loop, it is sent to the indoor unit for cooling after passing through the throttling device 4. The refrigerant that has absorbed heat in the indoor unit is divided into two parts: one part returns to the heat pump compressor 1 for circulation after passing through the four-way valve, and the other part flows back to the defrost compressor 16 in the defrost circulation loop through the second branch 14 for recirculation. It can be seen that the dual-system air conditioning unit with heat storage module proposed in this invention also involves the defrost compressor 16 in cooling operation during cooling operation, which improves the overall efficiency of the unit's cooling operation.

[0044] Variable frequency compressors are preferred for defrosting to control the actual output power of the compressor, thus controlling the amount of heat generated during defrosting of the outdoor heat exchanger. When the outdoor heat exchanger does not require defrosting or the frost is very light, the operating output power of the defrosting compressor is close to zero, and it can be shut down. As the frost on the outdoor heat exchanger worsens, the operating output power of the defrosting compressor is gradually increased to achieve rapid defrosting. With proper control logic and parameter control, the outdoor heat exchanger fan and indoor unit fan can remain running during heating operation without stopping due to defrosting, achieving uninterrupted continuous heating for the indoor unit and greatly improving air conditioning comfort.

[0045] Figure 1 In the embodiment shown, the first branch 8, the heat storage module 7, and the defrosting throttling device 9 are installed outdoors as part of the outdoor unit, located between the gas pipe and the liquid pipe on the side of the shut-off valve 6. This has the advantage of a compact air conditioning unit structure and convenient installation.

[0046] As an alternative embodiment, the first branch 8 and its associated heat storage module 7 and defrosting throttling device 9 can be installed outdoors as independent components, connected to the outdoor unit via pipes. This configuration requires the addition of two more shut-off valves 6 for the connecting pipes; see details below. Figure 2 The reason for installing the first branch 8 and its heat storage module 7 and defrosting throttling device 9 as independent components is that sometimes the installation location of the outdoor unit is limited, and the installation location of independent components can be flexible.

[0047] The dual-system heat pump air conditioning unit with heat storage module proposed in this invention can be used in a single-unit system or in a multi-unit air conditioning system.

[0048] The above description is merely a specific embodiment of the present invention. It should be noted that any modifications, equivalent substitutions, and variations made within the spirit and framework of the present invention should be included within the protection scope of the present invention.

Claims

1. An air conditioning unit, comprising: The heat pump circulation loop includes a heat pump compressor, an outdoor heat exchanger, and an indoor unit. The outdoor heat exchanger is provided with a third pipeline, the first end of which is connected to the outlet of the indoor unit and the second end of which is connected to the suction port of the heat pump compressor. The defrosting circulation loop includes a defrosting compressor, the outdoor heat exchanger, a first control valve, and a heat storage module. The outdoor heat exchanger is provided with a fourth pipeline, the first end of which is connected to the exhaust pipe of the defrosting compressor, and the second end of which is connected to the inlet end of the heat storage module. The first branch has one end connected to the first end of the third pipeline of the outdoor heat exchanger, and the other end connected to the exhaust pipe of the heat pump compressor. The first branch is equipped with a heat storage module and a heat storage throttling device. The feature is that it further includes: a second branch, one end of which is connected to the inlet of the indoor unit and the other end of which is connected to the air intake of the defrosting compressor, and a second control valve is provided on the second branch; and a third branch, one end of which is connected to the second end of the fourth pipe of the outdoor heat exchanger and the other end of which is connected to the first end of the third pipe of the outdoor heat exchanger, and a third control valve is provided on the third branch. During the refrigeration cycle, the second control valve and the third control valve are open, and the first control valve is closed.

2. The air conditioning unit as described in claim 1, characterized in that, The heat storage module includes a heat storage medium, a first pipeline connected to the heat pump circulation loop, and a second pipeline connected to the defrost circulation loop.

3. The air conditioning unit as described in claim 2, characterized in that, The heat storage medium is a mixture of graphite and paraffin.

4. The air conditioning unit as described in claim 2, characterized in that, The first pipeline and the second pipeline are arranged in an alternating pattern.

5. The air conditioning unit as described in claim 1, characterized in that, The third and fourth pipes in the outdoor heat exchanger are arranged in an alternating manner.

6. The air conditioning unit as described in claim 1, characterized in that, The heat storage module and the heat storage throttling device are integrated and can be detachably connected to the outdoor unit.

7. The air conditioning unit as described in claim 1, characterized in that, The heat storage module and the heat storage throttling device are installed inside the outdoor unit of the air conditioning unit.

8. The air conditioning unit as described in claim 1, characterized in that, When the defrosting cycle is in operation, the second control valve on the second branch and the third control valve on the third branch are closed, while the heat storage throttling device on the first branch and the defrosting throttling device and the first control valve at the front end of the heat storage module on the defrosting cycle are all open.

9. An air conditioning unit, comprising: The heat pump circulation loop includes a heat pump compressor, a four-way valve, an outdoor heat exchanger, a throttling device, and an indoor unit. The outdoor heat exchanger is provided with a third pipeline, the first end of which is connected to the outlet of the indoor unit and the second end of which is connected to the suction port of the heat pump compressor. The defrosting circulation loop includes a defrosting compressor, the outdoor heat exchanger, a first control valve, a check valve, a defrosting throttling device, and a heat storage module. The outdoor heat exchanger is provided with a fourth pipeline, the first end of which is connected to the exhaust pipe of the defrosting compressor, and the second end of which is connected to the inlet end of the heat storage module. The first branch has one end connected to the first end of the third pipe of the outdoor heat exchanger and the other end connected to the exhaust pipe of the heat pump compressor. The first branch is equipped with a heat storage module and a heat storage throttling device. The heat storage module is equipped with a first pipe and a second pipe. The first pipe is connected to the heat pump circulation loop and the second pipe is connected to the defrost circulation loop. The feature is that it further includes: a second branch, one end of which is connected to the inlet of the indoor unit and the other end of which is connected to the air intake of the defrosting compressor, wherein a second control valve and a one-way valve are provided on the second branch; and a third branch, one end of which is connected to the second end of the fourth pipe of the outdoor heat exchanger and the other end of which is connected to the first end of the third pipe of the outdoor heat exchanger, wherein a third control valve and a one-way valve are provided on the third branch. During the refrigeration cycle, the second control valve and the third control valve are open, and the first control valve is closed.

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