High positive drop air conditioner active oil return system and air conditioner

Abstract

The embodiment of the application discloses a high positive drop air conditioner active oil return system and an air conditioner, and is used for solving the technical problem that the compressor is easy to be short of oil due to long-time operation of the air conditioner in a high positive drop application scene. The compressor is connected with an air outlet pipe and an air suction pipe for connecting an indoor unit of the air conditioner; the oil return device comprises an oil storage tank, an air inlet pipe, an oil return pipe and an air outlet pipe for connecting an outdoor unit of the air conditioner, and the air inlet pipe is connected with the air outlet pipe, the oil return pipe is connected with a liquid pipe, and an oil pump is arranged on the oil return pipe. In the design, the weight difference between the gaseous refrigerant and the liquid lubricating oil is utilized, so that the liquid lubricating oil from the air outlet pipe is deposited into the oil storage tank due to the weight, the liquid lubricating oil in the oil storage tank is pumped into the liquid pipe by the oil pump, the refrigerant and the liquid lubricating oil can be recycled into the compressor through the indoor unit and the air suction pipe, and thus the oil return of the compressor is completed, and the above technical problem is effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioner oil return systems, and in particular to a high positive drop air conditioner active oil return system and an air conditioner. BACKGROUND

[0002] A large number of high positive drop application scenarios are encountered by a computer room precision air conditioner, that is, a compressor is installed in an indoor unit, the indoor unit is installed below, an outdoor unit is installed above, and the height difference is large (more than 30 m). When the air conditioner is running, lubricating oil in the system circulates with refrigerant. The refrigerant is gaseous in the gas pipe, and the lubricating oil is liquid. The two are in an incompatible state. When the positive drop of the connecting pipe between the indoor unit and the outdoor unit is too large, the liquid lubricating oil is difficult to circulate back into the compressor along with the refrigerant, resulting in damage to the compressor due to lack of oil.

[0003] Currently, air conditioner equipment manufacturers usually have two common processing methods:

[0004] 1. An oil separator is arranged at the outlet of the compressor to minimize the discharge of lubricating oil from the compressor, but the oil separator has efficiency problems, that is, it cannot separate 100% of the oil and refrigerant, and part of the lubricating oil will circulate out of the compressor along with the refrigerant, which will still cause the compressor to lack oil after a long period of operation.

[0005] 2. An oil return bend is arranged at intervals on the gas pipe. When the positive drop is large, there are many oil return bends. At this time, the engineering installation cost is greatly increased, and too high a drop and too many oil return bends will cause too much pressure loss to the system operation, resulting in the pressure on the high pressure side of the compressor exceeding the limit. At this time, the specification of the outdoor unit often needs to be configured to be larger, and the equipment cost is greatly increased. Increasing the oil return bend can only solve the oil return problem to a certain extent. Under a long period of operation of the air conditioner, the compressor is still prone to lack of oil. Moreover, when the positive drop exceeds a certain limit, increasing the oil return bend cannot achieve the purpose of improving the oil return effect.

[0006] Therefore, finding a high positive drop air conditioner active oil return system and an air conditioner that can solve the above technical problems has become an important topic for researchers in the field. SUMMARY

[0007] The embodiments of the present application disclose a high positive drop air conditioner active oil return system and an air conditioner, which are used to solve the technical problem that the compressor is prone to lack of oil under a long period of operation of the air conditioner in a high positive drop application scenario.

[0008] The embodiments of the present application provide a high positive drop air conditioner active oil return system, which comprises an oil return device, a compressor, and a liquid pipe for connecting an outdoor unit of the air conditioner and an indoor unit of the air conditioner.

[0009] The compressor is connected with an air outlet pipe and an air suction pipe for connecting an indoor unit of an air conditioner;

[0010] The oil return device comprises an oil tank, an air inlet pipe, an oil return pipe and an air outlet pipe for connecting an outdoor unit of an air conditioner;

[0011] The air inlet pipe is connected with the air outlet pipe, the oil return pipe is connected with the liquid pipe, and the oil pump is arranged on the oil return pipe.

[0012] Optionally, the oil tank is provided with a first liquid level sensor and a second liquid level sensor electrically connected with the oil pump, wherein the first liquid level sensor is higher than the second liquid level sensor.

[0013] Optionally, the system further comprises a first bypass pipe and a second bypass pipe;

[0014] The first bypass pipe is connected in parallel with the oil return pipe, the first bypass pipe is provided with a first control valve electrically connected with the first liquid level sensor and the second liquid level sensor, and the oil pump is located between two connection positions of the first bypass pipe and the oil return pipe.

[0015] The second bypass pipe is connected in parallel with the air outlet pipe, the air outlet pipe is provided with a second control valve electrically connected with the first liquid level sensor and the second liquid level sensor, and the second control valve is located between two connection positions of the second bypass pipe and the air outlet pipe.

[0016] Optionally, the diameter of the second bypass pipe is smaller than that of the air outlet pipe.

[0017] Optionally, the air inlet pipe is provided with a one-way valve.

[0018] Optionally, the air outlet pipe is connected to the top of the oil tank, and the oil return pipe and the air inlet pipe are connected to the bottom of the oil tank.

[0019] Optionally, the port of the air outlet pipe in the oil tank and the port of the air inlet pipe in the oil tank are arranged staggeredly.

[0020] Optionally, the port of the air outlet pipe in the oil tank is bent towards the inner side wall of the oil tank.

[0021] Alternatively, the port of the air inlet pipe in the oil tank is bent towards the inner side wall of the oil tank.

[0022] The embodiment of the application discloses an air conditioner, comprising an indoor unit and an outdoor unit, wherein the outdoor unit is located above the indoor unit, and the air conditioner further comprises the high positive drop active oil return system.

[0023] The high positive drop air conditioner active oil return system comprises an oil return device, a compressor and a liquid pipe connecting the outdoor unit and the indoor unit;

[0024] The compressor is installed in the indoor unit, and the compressor is connected with an air outlet pipe and an air inlet pipe connected with the indoor unit;

[0025] The oil return device comprises an oil tank and an air inlet pipe, an oil return pipe and an air outlet pipe connected with the oil tank;

[0026] The air outlet pipe is connected with the outdoor unit, the air inlet pipe is connected with the air outlet pipe, the oil return pipe is connected with the liquid pipe, and an oil pump is arranged on the oil return pipe.

[0027] Optionally, the indoor unit comprises an evaporator assembly, and the outdoor unit comprises a condenser assembly.

[0028] From the above technical solution, it can be seen that the embodiment of the present application has the following advantages:

[0029] In the embodiment, gaseous refrigerant and liquid lubricating oil enter the oil tank from the air outlet pipe through the air inlet pipe. Due to the different weights of gaseous refrigerant and liquid lubricating oil, the liquid lubricating oil from the air outlet pipe deposits into the oil tank due to the weight, and the liquid lubricating oil in the oil tank is then pumped into the liquid pipe by the oil pump, so that the refrigerant and the liquid lubricating oil can be recycled together through the indoor unit, the air inlet pipe and then back to the compressor, thereby completing the oil return of the compressor, and the gaseous refrigerant enters the outdoor unit from the air outlet pipe of the oil tank to continue the refrigeration cycle. Through the above design, the technical problem that the air conditioner is prone to oil shortage of the compressor during long-time operation in the high positive drop application scenario is effectively solved, and the reliability of the air conditioner in the high positive drop application scenario is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0031] Fig. 1 It is a structural schematic diagram of an air conditioner provided in the embodiment of the present application;

[0032] Fig. 2 It is a structural schematic diagram of a high positive drop air conditioner active oil return system provided in the embodiment of the present application;

[0033] Compressor 1; oil return device 2; oil tank 201; oil return pipe 202; oil pump 203; air inlet pipe 204; air outlet pipe 205; first bypass pipe 206; first control valve 207; second bypass pipe 208; second control valve 209; first liquid level sensor 210; second liquid level sensor 211; one-way valve 212; air outlet pipe 3; air inlet pipe 4; liquid pipe 5; indoor unit 6; outdoor unit 7. DETAILED DESCRIPTION

[0034] The embodiment of the application discloses a high positive drop air conditioner active oil return system and an air conditioner, and aims to solve the technical problem that the compressor is prone to oil shortage after long-time operation in a high positive drop application scenario.

[0035] In order to enable the personnel in the technical field to better understand the application scheme, the application is further described in detail below in combination with the drawings and specific embodiments. Obviously, the described embodiments are only some of the embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by the person skilled in the art without creative labor fall within the protection scope of the application.

[0036] Embodiment one

[0037] Please refer to Figs. 1-2 The high positive drop air conditioner active oil return system provided in the embodiment of the application comprises:

[0038] an oil return device 2, a compressor 1, and a liquid pipe 5 for connecting an outdoor unit 7 of the air conditioner and an indoor unit 6 of the air conditioner;

[0039] The compressor 1 is connected with an air outlet pipe 3 and an air inlet pipe 4 for connecting the indoor unit 6 of the air conditioner;

[0040] The oil return device 2 comprises an oil tank 201, an air inlet pipe 204, an oil return pipe 202 and an air outlet pipe 205 connected with the oil tank 201 and used for connecting the outdoor unit 7 of the air conditioner;

[0041] The air inlet pipe 204 is connected with the air outlet pipe 3, the oil return pipe 202 is connected with the liquid pipe 5, and the oil pump 203 is arranged on the oil return pipe 202.

[0042] In this embodiment, gaseous refrigerant and liquid lubricating oil enter the oil tank 201 from the gas outlet pipe 3 through the gas inlet pipe 204. Due to the different weights of gaseous refrigerant and liquid lubricating oil, the liquid lubricating oil from the gas outlet pipe 3 deposits into the oil tank 201 due to the weight. The liquid lubricating oil in the oil tank 201 is then pumped into the liquid pipe 5 by the oil pump 203, so that the refrigerant and the liquid lubricating oil can be recycled together through the indoor unit 6, the suction pipe 4, and then back to the compressor 1, thereby completing the oil return of the compressor 1. The gaseous refrigerant enters the outdoor unit 7 from the exhaust pipe 205 of the oil tank 201 to continue the refrigeration cycle. Through the above design, the technical problem that the compressor 1 is prone to oil shortage due to long-time operation of the air conditioner in a high positive drop application scenario is effectively solved, and the reliability of the air conditioner in a high positive drop application scenario is greatly improved. In addition, compared with the current method of setting an oil return bend to achieve oil return, the above design can greatly reduce the engineering installation amount and installation cost.

[0043] Further, the oil tank 201 in the embodiment is provided with a first liquid level sensor 210 and a second liquid level sensor 211 electrically connected with the oil pump 203, wherein the first liquid level sensor 210 is higher than the second liquid level sensor 211.

[0044] It should be noted that the heights of the first liquid level sensor 210 and the second liquid level sensor 211 are set differently, which are mainly used for detecting the high liquid level and the low liquid level of the liquid lubricating oil in the oil tank 201. It can be simply understood that the designer can select appropriate heights as the high liquid level and the low liquid level according to actual design requirements.

[0045] When the first liquid level sensor 210 detects the liquid level of the liquid lubricating oil, the oil pump 203 is started, and the oil pump 203 pumps the liquid lubricating oil in the oil tank 201 into the liquid pipe 5 to realize the oil return of the compressor 1.

[0046] When the second liquid level sensor 211 detects the liquid level of the liquid lubricating oil, the oil pump 203 stops.

[0047] Further, in order to enable the oil return system to still realize oil return when the oil pump 203 fails, the embodiment further includes a first bypass pipe 206 and a second bypass pipe 208.

[0048] The first bypass pipe 206 is connected in parallel with the oil return pipe 202, the first bypass pipe 206 is provided with a first control valve 207 electrically connected with the first liquid level sensor 210 and the second liquid level sensor 211, and the oil pump 203 is located between two connection positions of the first bypass pipe 206 and the oil return pipe 202.

[0049] The second bypass pipe 208 is connected in parallel to the exhaust pipe 205, and a second control valve 209 electrically connected to the first liquid level sensor 210 and the second liquid level sensor 211 is arranged on the exhaust pipe 205, and the second control valve 209 is located between the two connection positions of the second bypass pipe 208 and the exhaust pipe 205.

[0050] It should be noted that when the oil pump 203 in the embodiment is normally working, the second control valve 209 is opened, the first control valve 207 is closed, and the oil pump 203 pumps the lubricating oil in the oil tank 201 into the liquid pipe 5 to realize the oil return of the compressor 1.

[0051] When the oil pump 203 in the embodiment fails to work normally, the second control valve 209 is closed, and the first control valve 207 is opened. At this time, the gaseous refrigerant in the oil tank 201 is discharged at a low rate, and therefore, the pressure in the oil tank 201 is increased, and the liquid lubricating oil in the oil tank 201 flows into the liquid pipe 5 from the oil return pipe 202 through the first bypass pipe 206 to realize the oil return of the compressor 1.

[0052] The first control valve 207 and the second control valve 209 are preferably electromagnetic valves.

[0053] Preferably, the diameter of the second bypass pipe 208 is smaller than the diameter of the exhaust pipe 205. It should be noted that through the above design, the discharge rate of the gaseous refrigerant can be slowed down as much as possible to realize that the internal pressure of the oil tank 201 can be increased faster when the oil pump 203 fails, thereby automatically making the compressor 1 return oil.

[0054] Further, the inlet pipe 204 in the embodiment is provided with a one-way valve 212.

[0055] It should be noted that through the above design, the lubricating oil and the refrigerant can be prevented from flowing back into the compressor 1, thereby causing liquid impact on the compressor 1.

[0056] Further, the exhaust pipe 205 in the embodiment is connected to the top of the oil tank 201, and the oil return pipe 202 and the inlet pipe 204 are connected to the bottom of the oil tank 201.

[0057] It should be noted that after the liquid lubricating oil and the gaseous refrigerant enter the oil tank 201, the liquid lubricating oil will deposit in the oil tank 201, and the gaseous refrigerant will flow to the top of the oil tank 201. Therefore, through the above design, the lubricating oil in the oil tank 201 can better enter the oil return pipe 202, and the gaseous refrigerant can better flow out of the exhaust pipe 205 of the oil tank 201.

[0058] Further, in one specific embodiment, the exhaust pipe 205 in the embodiment is arranged at a port in the oil tank 201 offset from a port in the oil tank 201 where the air inlet pipe 204 is arranged.

[0059] It should be noted that, through the above design, the exhaust pipe 205 and the air inlet pipe 204 are not arranged in the same line, which effectively prevents the lubricating oil from directly entering the exhaust pipe 205 from the air inlet pipe 204, hinders the lubricating oil from remaining in the oil tank 201, and also prevents the lubricating oil deposited from the exhaust pipe 205 from re-entering the air inlet pipe 204.

[0060] In another specific embodiment, the exhaust pipe 205 in the embodiment is arranged at a port in the oil tank 201 bent towards the inner side wall of the oil tank 201.

[0061] Alternatively, the air inlet pipe 204 is arranged at a port in the oil tank 201 bent towards the inner side wall of the oil tank 201.

[0062] It should be noted that, through the above design, the exhaust pipe 205 and the air inlet pipe 204 are not arranged in the same line, which effectively prevents the lubricating oil from directly entering the exhaust pipe 205 from the air inlet pipe 204, hinders the lubricating oil from remaining in the oil tank 201, and also prevents the lubricating oil deposited from the exhaust pipe 205 from re-entering the air inlet pipe 204.

[0063] Further, the oil tank 201 in the embodiment is preferably in a long strip structure, which is more conducive to the installation of the oil tank 201 together with the pipeline through the above design, and the long strip structure occupies less space.

[0064] Based on the high positive drop air conditioning active oil return system according to the above structure, the embodiment also provides a specific working mode of the oil return system:

[0065] Pump oil return mode:

[0066] The gaseous refrigerant and liquid lubricating oil from the compressor 1 through the air outlet pipe 3 enter the oil tank 201 through the air inlet pipe 204 and the one-way valve 212. The liquid lubricating oil will be deposited in the oil tank 201 due to the action of gravity, and the gaseous refrigerant will enter the outdoor unit 7 to perform a refrigeration cycle. When the liquid level of the lubricating oil reaches the position of the first liquid level sensor 210, the oil pump 203 will start to operate, and when the liquid level of the lubricating oil drops to the position of the second liquid level sensor 211, the oil pump 203 will stop operating.

[0067] Pressure oil return mode:

[0068] When the oil pump 203 fails, the liquid level of the liquid lubricating oil reaches the position of the first liquid level sensor 210, the second control valve 209 is closed, and the first control valve 207 is opened. At this time, the pressure in the oil tank 201 will rise, so that the pressure in the oil tank 201 is greater than the pressure in the liquid pipe 5. The liquid lubricating oil enters the liquid pipe 5 through the oil return pipe 202 due to the pressure difference, and circulates back to the compressor 1 along with the liquid refrigerant. When the liquid level of the lubricating oil is detected to reach the position of the second liquid sensor 211, the second control valve 209 is opened, the first control valve 207 is closed, and the oil return operation is ended.

[0069] In addition, when it is detected that the first liquid level sensor 210 fails, a fixed time interval oil return control is adopted, that is, the compressor 1 is continuously operated for 6h for oil return once;

[0070] When it is detected that the second liquid level sensor 211 fails, a fixed time interval oil return control is adopted, that is, oil return starts when the liquid level of the lubricating oil reaches the position of the first liquid level sensor 210, and oil return ends after 1min (the duration is determined by the volume of the oil tank 201 and the flow rate of the oil pump 203);

[0071] When it is detected that the first liquid level sensor 210 and the second liquid level sensor 211 both fail, a fixed time interval and fixed time length oil return control is adopted, that is, the compressor 1 is continuously operated for 6h for oil return once, and the oil return duration is 1min;

[0072] Embodiment two

[0073] Please refer to Fig. 1 River Fig. 2 , the air conditioner provided in the embodiment of the application, which is specifically an air conditioner used in a high positive drop application scenario, specifically comprises an indoor unit 6 and an outdoor unit 7, wherein the outdoor unit 7 is located above the indoor unit 6, and further comprises the high positive drop air conditioner active oil return system as described in embodiment one;

[0074] The high positive drop air conditioner active oil return system comprises an oil return device 2, a compressor 1, and a liquid pipe 5 connecting the outdoor unit 7 and the indoor unit 6.

[0075] The compressor 1 is installed in the indoor unit 6, and the compressor 1 is connected with an air outlet pipe 3 and an air inlet pipe 4 connected with the indoor unit 6.

[0076] The oil return device 2 comprises an oil tank 201, an air inlet pipe 204, an oil return pipe 202, and an air outlet pipe 205 connected with the oil tank 201.

[0077] The air outlet pipe 205 is connected with the outdoor unit 7, the air inlet pipe 204 is connected with the air outlet pipe 3, the oil return pipe 202 is connected with the liquid pipe 5, and the oil pump 203 is arranged on the oil return pipe 202.

[0078] In the embodiment, the gaseous refrigerant and the liquid lubricating oil enter the oil storage tank 201 from the gas outlet pipe 3 through the gas inlet pipe 204. Due to the different weights of the gaseous refrigerant and the liquid lubricating oil, the liquid lubricating oil from the gas outlet pipe 3 deposits into the oil storage tank 201 due to the weight. The liquid lubricating oil in the oil storage tank 201 is then pumped into the liquid pipe 5 by the oil pump 203, so that the refrigerant and the liquid lubricating oil can be recycled together through the indoor unit 6, the suction pipe 4, and then back to the compressor 1, thereby completing the oil return of the compressor 1. The gaseous refrigerant enters the outdoor unit 7 from the gas outlet pipe 205 of the oil storage tank 201 to continue the refrigeration cycle. Through the above design, the technical problem that the compressor 1 is prone to lack of oil due to long-time operation of the air conditioner in the high positive drop application scenario is effectively solved, and the reliability of the air conditioner in the high positive drop application scenario is greatly improved.

[0079] Further, the indoor unit 6 in the embodiment includes an evaporator assembly, and the outdoor unit 7 in the embodiment includes a condenser assembly.

[0080] It should be noted that the indoor unit 6 described above includes an evaporator assembly, which is mainly used to make the refrigerant complete the transformation from liquid state to gaseous state in the evaporator assembly. The outdoor unit 7 includes a condenser assembly, which is mainly used to make the refrigerant complete the transformation from gaseous state to liquid state in the condenser assembly. The liquid refrigerant returns to the evaporator assembly through the liquid pipe 5, and the refrigeration cycle is thus performed.

[0081] The evaporator assembly and the condenser assembly described above are both known in the art, and therefore, the specific structures of the two are not further described in the embodiment, and the specific structures of the evaporator assembly and the condenser assembly are not limited in the embodiment. Designers can select appropriate evaporator assemblies and condenser assemblies according to actual needs.

[0082] The high positive drop air conditioner active oil return system and the air conditioner provided by the application are described in detail above. For those skilled in the art, the specific implementation and application range can be changed according to the idea of the embodiment of the application. In view of the above, the content of the specification should not be understood as a limitation of the application.

Claims

1. A high positive drop air conditioning active oil return system, characterized in that, Includes an oil return device (2), a compressor (1), and a liquid pipe (5) for connecting the outdoor unit (7) of the air conditioner to the indoor unit (6) of the air conditioner. The compressor (1) is connected to an outlet pipe (3) and an intake pipe (4) for connecting to the indoor unit (6) of the air conditioner. The oil return device (2) includes an oil storage tank (201), an air inlet pipe (204), an oil return pipe (202), and an exhaust pipe (205) for connecting the oil storage tank (201) to the outdoor unit (7) of the air conditioner. The air inlet pipe (204) is connected to the air outlet pipe (3), the oil return pipe (202) is connected to the liquid pipe (5), and an oil pump (203) is installed on the oil return pipe (202). The oil storage tank (201) is equipped with a first liquid level sensor (210) and a second liquid level sensor (211) that are electrically connected to the oil pump (203), wherein the first liquid level sensor (210) is higher than the second liquid level sensor (211). The liquid lubricating oil in the oil storage tank (201) is then pumped into the liquid pipe (5) by the oil pump (203), so that the refrigerant and liquid lubricating oil can be recycled back into the compressor (1) through the indoor unit (6) and the suction pipe (4), thereby completing the oil return of the compressor (1).

2. The high positive drop air conditioning active oil return system according to claim 1, characterized in that, It also includes a first bypass pipe (206) and a second bypass pipe (208); The first bypass pipe (206) is connected in parallel to the return oil pipe (202). The first bypass pipe (206) is provided with a first control valve (207) that is electrically connected to the first liquid level sensor (210) and the second liquid level sensor (211). The oil pump (203) is located between the two connection points of the first bypass pipe (206) and the return oil pipe (202). The second bypass pipe (208) is connected in parallel to the exhaust pipe (205). The exhaust pipe (205) is provided with a second control valve (209) that is electrically connected to the first liquid level sensor (210) and the second liquid level sensor (211). The second control valve (209) is located between the two connection points of the second bypass pipe (208) and the exhaust pipe (205).

3. The high positive drop air conditioning active oil return system according to claim 2, characterized in that, The diameter of the second bypass pipe (208) is smaller than the diameter of the exhaust pipe (205).

4. The high positive drop air conditioning active oil return system according to claim 1, characterized in that, A one-way valve (212) is provided on the air intake pipe (204).

5. The high positive drop air conditioning active oil return system according to claim 1, characterized in that, The exhaust pipe (205) is connected to the top of the oil storage tank (201), and the return oil pipe (202) and the air inlet pipe (204) are both connected to the bottom of the oil storage tank (201).

6. The high positive drop air conditioning active oil return system according to claim 5, characterized in that, The port of the exhaust pipe (205) located inside the oil storage tank (201) is offset from the port of the air intake pipe (204) located inside the oil storage tank (201).

7. The high positive drop air conditioning active oil return system according to claim 5, characterized in that, The port of the exhaust pipe (205) located inside the oil storage tank (201) is bent toward the inner wall of the oil storage tank (201); Alternatively, the port of the air inlet pipe (204) located inside the oil storage tank (201) is bent toward the inner wall of the oil storage tank (201).

8. An air conditioner comprising an indoor unit (6) and an outdoor unit (7), wherein the outdoor unit (7) is located above the indoor unit (6), characterized in that, It also includes the high positive drop air conditioning active oil return system as described in any one of claims 1 to 7; The high positive drop air conditioning active oil return system includes an oil return device (2), a compressor (1), and a liquid pipe (5) connecting the outdoor unit (7) and the indoor unit (6). The compressor (1) is installed inside the indoor unit (6), and the compressor (1) is connected to an air outlet pipe (3) and an air intake pipe (4) connected to the indoor unit (6). The oil return device (2) includes an oil storage tank (201) and an air inlet pipe (204), an oil return pipe (202) and an exhaust pipe (205) connected to the oil storage tank (201). The exhaust pipe (205) is connected to the outdoor unit (7), the air inlet pipe (204) is connected to the air outlet pipe (3), the oil return pipe (202) is connected to the liquid pipe (5), and an oil pump (203) is installed on the oil return pipe (202).

9. The air conditioner according to claim 8, characterized in that, The indoor unit (6) includes an evaporator assembly, and the outdoor unit (7) includes a condenser assembly.

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