Air conditioning unit

Abstract

The utility model discloses an air conditioning unit. The air conditioning unit comprises a compressor, an oil tank, an evaporator and a cooling separator. The oil tank is connected with the compressor and used for receiving high-temperature lubricating oil output by the compressor. The cooling separator is connected with the oil groove and the evaporator and used for separating the mixture of the low-temperature lubricating oil and the liquid refrigerant output by the evaporator and receiving the high-temperature lubricating oil, so that the mixture of the low-temperature lubricating oil and the liquid refrigerant exchanges heat with the high-temperature lubricating oil, and medium-temperature lubricating oil is obtained. The cooling separator is further connected with an air suction port of the compressor so that the liquid refrigerant can be gasified into a gaseous refrigerant. The oil groove is further used for receiving medium-temperature lubricating oil. The compressor is used for receiving and compressing a gaseous refrigerant. The liquid refrigerant is gasified in the cooling separator instead of being gasified in the oil tank, and the low-temperature lubricating oil is kept at a higher temperature after heat exchange, so that the problem of lower oil temperature of the lubricating oil caused by the gasification of the liquid refrigerant in the oil tank is avoided, and the air conditioning unit is prevented from alarming and stopping caused by unstable oil supply.

Description

TECHNICAL FIELD

[0001] The utility model relates to air conditioning technical field especially relates to a kind of air conditioning units. BACKGROUND

[0002] To ensure the stable operation of the compressor of air conditioning unit, the lubrication of mechanical bearing in the compressor is very important. In the related art, the air conditioning unit is provided with an oil sump connected with the compressor, and the oil sump stores lubricating oil used for lubricating the mechanical bearing. During the operation of the air conditioning unit, the mutual solubility of the lubricating oil and the liquid refrigerant will inevitably occur. In order to ensure the reliability of the air conditioning unit, the mixture of the lubricating oil and the liquid refrigerant in the evaporator is injected into the oil sump. However, the gasification of the liquid refrigerant in the oil sump will reduce the oil temperature of the lubricating oil, which will increase the solubility of the liquid refrigerant in the lubricating oil, thereby reducing the viscosity of the lubricating oil, and the flashing of the liquid refrigerant at the pump inlet of the lubricating oil will cause unstable oil supply, thereby causing the air conditioning unit to stop working and alarm. SUMMARY

[0003] The utility model provides a kind of air conditioning unit to solve at least one technical problem existing in the above.

[0004] The air conditioning unit of the utility model embodiment comprises a compressor, an oil sump, an evaporator and a cooling separator. The oil sump is connected with the compressor and is used for receiving high-temperature lubricating oil output by the compressor. The cooling separator is connected with the oil sump and the evaporator and is used for separating the mixture of low-temperature lubricating oil and liquid refrigerant output by the evaporator and receiving the high-temperature lubricating oil, so that the mixture of the low-temperature lubricating oil and the liquid refrigerant exchanges heat with the high-temperature lubricating oil to obtain medium-temperature lubricating oil. The cooling separator is also connected with the suction port of the compressor to make the liquid refrigerant gasify into gaseous refrigerant. The oil sump is also used for receiving the medium-temperature lubricating oil. The compressor is used for receiving and compressing the gaseous refrigerant.

[0005] In the air conditioning unit of the utility model embodiment, the cooling separator receives high-temperature lubricating oil and makes the mixture of low-temperature lubricating oil and liquid refrigerant exchange heat with the high-temperature lubricating oil to obtain medium-temperature lubricating oil. In this process, the liquid refrigerant gasifies in the cooling separator instead of the oil sump, and the low-temperature lubricating oil maintains a relatively high temperature after heat exchange, thereby avoiding the problem that the oil temperature of the lubricating oil is relatively low due to the gasification of the liquid refrigerant in the oil sump, avoiding the problem that the viscosity of the lubricating oil is reduced, ensuring the good lubricating performance of the lubricating oil, and avoiding the flashing of the liquid refrigerant at the pump inlet of the lubricating oil, ensuring the stability of oil supply and preventing the air conditioning unit from stopping working and alarming due to unstable oil supply.

[0006] In addition, the gaseous refrigerant can be received and compressed by the compressor, improving the utilization rate of the gaseous refrigerant, reducing the waste of the refrigerant, and reducing the operation cost of the system.

[0007] In some embodiments, the compressor comprises a compressor oil outlet, the compressor is configured to output the high-temperature lubricating oil through the compressor oil outlet, and the oil groove comprises an oil groove oil inlet, the oil groove oil inlet being in communication with the compressor oil outlet.

[0008] In some embodiments, the air conditioning unit further comprises a condenser, the condenser comprises a first gas outlet, the evaporator comprises a first fluid outlet, the cooling separator further comprises a fluid inlet, and the air conditioning unit further comprises a first ejector, the first ejector comprises a first ejector inlet, a second ejector inlet, and a first ejector outlet, the first ejector is configured to inject the mixture of the low-temperature lubricating oil and the liquid refrigerant output by the evaporator into the cooling separator, the first ejector inlet is in communication with the first gas outlet, the first fluid outlet is in communication with the second ejector inlet, and the first ejector outlet is in communication with the fluid inlet.

[0009] In some embodiments, the air conditioning unit further comprises a first regulating valve, the first regulating valve comprises a first valve inlet and a first valve outlet, the first valve inlet is in communication with the first ejector outlet, and the first valve outlet is in communication with the fluid inlet.

[0010] In some embodiments, the cooling separator comprises a second gas outlet, the second gas outlet is in communication with the suction port of the compressor.

[0011] In some embodiments, the cooling separator is provided with a first filter connected with two opposite side walls in the cooling separator, the first filter is arranged between the second gas outlet and the fluid inlet, and the first filter is configured to separate the medium-temperature lubricating oil and the gaseous refrigerant flowing from the fluid inlet to the second gas outlet.

[0012] In some embodiments, the air conditioning unit comprises an oil pump and a heat exchanger, the oil pump is arranged in the oil groove, the heat exchanger is arranged in the cooling separator, the oil pump comprises a pump outlet, the oil pump is configured to pump the high-temperature lubricating oil into the heat exchanger through the pump outlet, and the heat exchanger comprises an exchanger oil inlet, the exchanger oil inlet being in communication with the pump outlet.

[0013] In some embodiments, the heat exchanger further comprises an exchanger oil outlet, the compressor comprises a compressor oil inlet, the compressor oil inlet is configured to receive the high-temperature lubricating oil after heat exchange with the low-temperature lubricating oil and the liquid refrigerant, and the exchanger oil outlet is in communication with the compressor oil inlet.

[0014] In some embodiments, the air conditioning unit further comprises a condenser and a second ejector, the second ejector comprising a third ejector inlet, a fourth ejector inlet and a second ejector outlet, the second ejector being configured to draw the medium temperature lubricating oil and the partial gaseous refrigerant in the cooling separator into the oil tank under the action of high pressure gas outputted by the condenser, the condenser comprising a second gas outlet, the cooling separator comprising a second fluid outlet, the oil tank comprising an oil tank fluid inlet, the second gas outlet being in communication with the third ejector inlet, the second fluid outlet being in communication with the fourth ejector inlet, and the second ejector outlet being in communication with the oil tank fluid inlet.

[0015] In some embodiments, the oil tank comprises an oil tank gas outlet, the oil tank being configured to supply the gaseous refrigerant to the compressor through the oil tank gas outlet, the oil tank gas outlet being in communication with the suction port of the compressor.

[0016] In some embodiments, the oil tank is provided with a second filter connected with two opposite side walls of the oil tank, the second filter being arranged between the oil tank gas outlet and the oil tank fluid inlet, and the second filter being configured to separate the lubricating oil and the gaseous refrigerant flowing from the oil tank fluid inlet to the oil tank gas outlet.

[0017] In some embodiments, the air conditioning unit further comprises a second regulating valve, the second regulating valve comprising a second valve inlet and a second valve outlet, the second valve inlet being in communication with the second ejector outlet, and the second valve outlet being in communication with the oil tank fluid inlet.

[0018] Additional aspects and advantages of the present application will be made apparent from the following description of embodiments of the present application, given by way of example only, and from the appended claims. BRIEF DESCRIPTION OF DRAWINGS

[0019] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description of embodiments of the present application, given by way of example only, and from the appended claims.

[0020] Figure 1 is a structural diagram of an air conditioning unit according to an embodiment of the present application.

[0021] BRIEF DESCRIPTION OF DRAWINGS

[0022] Air conditioning unit 100; compressor 10; oil tank 20; evaporator 30; cooling separator 40; suction port 11 of compressor; condenser 50; throttle valve 60; refrigerant pipe 70; oil outlet 12 of compressor; oil inlet 21 of oil tank; first gas outlet 51; first fluid outlet 31; fluid inlet 41; first ejector 80; first ejector inlet 81; second ejector inlet 82; first ejector outlet 83; first regulating valve 90; first valve inlet 91; first valve outlet 92; second gas outlet 42; first filter 101; oil pump 102; heat exchanger 103; pump outlet 1020; exchanger oil inlet 1030; exchanger oil outlet 1031; compressor oil inlet 13; second ejector 104; third ejector inlet 1040; fourth ejector inlet 1041; second ejector outlet 1042; second gas outlet 52; second fluid outlet 43; oil tank fluid inlet 22; oil tank gas outlet 23; second filter 105; second regulating valve 106; second valve inlet 1060; second valve outlet 1061; oil heater 107. DETAILED DESCRIPTION

[0023] Embodiments of the present application will be described in detail below with reference to the drawings, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, and should not be understood as limiting the present application.

[0024] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0025] In the description of the utility model, it needs to explain, unless another explicit provision and limitation, the term "installation", "link", "connection" should do the broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected;Can be mechanical connection, also can be electrical connection or can communicate with each other;It can be directly connected, also can be indirectly connected through intermediate medium, can be the communication or the interaction of two elements of two elements inside.For ordinary skilled in the art, the above-mentioned terms can be understood according to the specific meaning in the utility model.

[0026] In the utility model, unless another explicit provision and limitation, the first feature is "on" or "under" the second feature can include the first and second features direct contact, also can include the first and second features are not direct contact but contact through the additional features between them.Moreover, the first feature is "on", "above" and "on" the second feature includes the first feature is directly above and obliquely above the second feature, or just indicates that the first feature is higher than the second feature in horizontal height.The first feature is "under", "below" and "under" the second feature includes the first feature is directly below and obliquely below the second feature, or just indicates that the first feature is less than the second feature in horizontal height.

[0027] The following disclosure provides many different embodiments or examples for implementing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the utility model. In addition, the utility model can refer to the same reference numerals and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides examples of various specific processes and materials, but those skilled in the art can realize the application of other processes and / or the use of other materials.

[0028] During the operation of the air conditioning unit, the mutual solubility of lubricating oil and refrigerant will inevitably occur. And with the circulation of the refrigerant, a large amount of lubricating oil and refrigerant exists in the evaporator of the air conditioning unit. The mixture of lubricating oil and refrigerant will reduce the heat transfer efficiency, and in severe cases, will cause liquid suction and damage the compressor.

[0029] The cooling of lubricating oil can be divided into two kinds. One of the cooling methods is water cooling, which is to realize the cooling of lubricating oil by heat exchange between cooling water and lubricating oil. However, this way has low heat exchange efficiency, needs to consume additional power, and reduces the efficiency of the air conditioning unit. In addition, the water cooling method is easy to scale and block, has low reliability, and has high maintenance cost.

[0030] Another cooling method is refrigerant cooling, specifically, a part of subcooled liquid refrigerant is drawn from the bottom of the condenser using system pressure difference as driving force, and after throttling by an electronic expansion valve, the liquid refrigerant enters a plate heat exchanger and high-temperature lubricating oil to exchange heat, thereby achieving cooling of the lubricating oil. However, this cooling method requires a high-efficiency plate heat exchanger and an electronic expansion valve, and the cost is high. When the system operates at partial load or small pressure difference, the system pressure difference becomes small, and the driving force is insufficient, which easily causes insufficient cooling of the lubricating oil. In addition, the gaseous refrigerant generated in the process of cooling the lubricating oil is sucked into the compressor after entering the evaporator and is discharged to the condenser after being compressed, and the compressor needs to consume additional power when compressing the part of gaseous refrigerant, which reduces the system efficiency.

[0031] Meanwhile, the mixture of the lubricating oil and the liquid refrigerant is injected back to the oil sump through the ejector, which causes a large amount of liquid refrigerant to evaporate into gas in the oil sump. The liquid refrigerant absorbs heat during evaporation, thereby causing the temperature of the lubricating oil to drop. This increases the solubility of the liquid refrigerant in the lubricating oil, thereby causing the viscosity of the lubricating oil to decrease, and at the same time, the liquid refrigerant flashes at the pump inlet of the lubricating oil, causing unstable oil supply, and further causing the air conditioning unit to stop running.

[0032] In addition, a large amount of gaseous refrigerant in the oil sump entrains oil droplets to flow at a high flow rate to the pipeline connecting the oil sump and the suction port of the compressor and escapes, which reduces the separation efficiency of the filter screen in the oil sump, causing the air conditioning unit to run out of oil, thereby affecting the heat exchange efficiency and reducing the performance of the air conditioning unit, and even causing the air conditioning unit to be unable to run due to lack of oil.

[0033] The air conditioning unit 100 of the embodiment of the present application comprises a compressor 10, an oil sump 20, an evaporator 30 and a cooling separator 40. The oil sump 20 is connected with the compressor 10 and is used to receive high-temperature lubricating oil output by the compressor 10. The cooling separator 40 is connected with the oil sump 20 and the evaporator 30 and is used to separate the mixture of low-temperature lubricating oil and liquid refrigerant output by the evaporator 30 and receive high-temperature lubricating oil, so that the mixture of low-temperature lubricating oil and liquid refrigerant exchanges heat with the high-temperature lubricating oil to obtain medium-temperature lubricating oil. The cooling separator 40 is also connected with a suction port 11 of the compressor 10, so that the liquid refrigerant is gasified into gaseous refrigerant. The oil sump 20 is also used to receive medium-temperature lubricating oil. The compressor 10 is used to receive and compress gaseous refrigerant.

[0034] In the air conditioning unit 100 of the embodiment of the present application, the cooling separator 40 receives high-temperature lubricating oil, and exchanges heat between the mixture of low-temperature lubricating oil and liquid refrigerant and the high-temperature lubricating oil, to obtain medium-temperature lubricating oil. In this process, the liquid refrigerant is vaporized in the cooling separator 40 instead of being vaporized in the oil tank 20, and the low-temperature lubricating oil maintains a high temperature after heat exchange, thereby avoiding the problem of low oil temperature of the lubricating oil caused by vaporization of the liquid refrigerant in the oil tank 20, avoiding the problem of reduced viscosity of the lubricating oil, ensuring good lubricating performance of the lubricating oil, and avoiding flash vaporization of the liquid refrigerant at the inlet of the lubricating oil pump, ensuring the stability of oil supply, and preventing the air conditioning unit 100 from alarming and stopping due to unstable oil supply.

[0035] In addition, the gaseous refrigerant can be received and compressed by the compressor 10, improving the utilization rate of the gaseous refrigerant, reducing the waste of the refrigerant, and reducing the operating cost of the system. Since the high-cost plate heat exchanger and electronic expansion valve are not used, the cost of the air conditioning unit 100 is reduced.

[0036] In addition, since heat exchange can be achieved without the help of additional liquid refrigerant and cooling water, additional power consumption is not required, which helps to improve the operating efficiency of the air conditioning unit 100. Since cooling water is not used, the abnormal stop of the air conditioning unit 100 caused by fouling and clogging of the cooling water is avoided.

[0037] Specifically, the air conditioning unit 100 can further include a condenser 50 and a throttling valve 60. The compressor 10, the condenser 50, the throttling valve 60, and the evaporator 30 are connected by a refrigerant pipeline 70. In the working process, the compressor 10 inhales the gaseous refrigerant evaporated by heat absorption from the evaporator 30, and discharges the gaseous refrigerant into the condenser 50 after compression. The gaseous refrigerant is cooled to high-temperature and high-pressure liquid refrigerant in the condenser 50. The liquid refrigerant becomes a low-temperature and low-pressure gas-liquid mixture after the throttling valve 60, and enters the evaporator 30 to continue to be heated to become a gas, and so on.

[0038] It should be noted that, Figure 1 The arrows on the refrigerant pipeline 70 indicate the flow direction of the refrigerant or the lubricating oil, but this is only a schematic for easy understanding, and cannot be regarded as a limitation on the embodiment of the present application.

[0039] The compressor 10 can be a reciprocating compressor 10, a screw compressor 10, a scroll compressor 10, etc. In the operating process of the air conditioning unit 100, in order to maintain the stable operation of the compressor 10, lubricating oil with appropriate flow and temperature is required to continuously cool and lubricate the bearings in the compressor 10.

[0040] The oil tank 20 receives the high-temperature lubricating oil output by the compressor 10 and stores it for subsequent use. The oil tank 20 can be a container of a circular, square or other shape and can be made of metal, plastic or the like.

[0041] The high-temperature lubricating oil is lubricating oil of a relatively high temperature due to the temperature of the bearings in the compressor 10. During the lubrication of the bearings in the compressor 10, the temperature generated when the bearings are in operation is transferred to the lubricating oil, thereby generating high-temperature lubricating oil of a relatively high temperature. Subsequently, the high-temperature lubricating oil is transported into the oil tank 20 for recovery.

[0042] The evaporator 30 absorbs the heat of indoor air through the evaporation process of the refrigerant, thereby reducing the temperature of the air. The evaporator 30 can be a direct expansion evaporator 30, a water-cooled evaporator 30 or the like.

[0043] The condenser 50 condenses the gaseous refrigerant into liquid refrigerant through heat dissipation and releases heat. The condenser 50 can be a shell-and-tube condenser 50, a plate condenser 50 or the like.

[0044] The cooling separator 40 is a component for separating the mixture of low-temperature lubricating oil and liquid refrigerant and performing heat exchange. The cooling separator 40 can be a box, a tank or the like. The cooling separator 40 can receive the high-temperature lubricating oil from the oil tank 20. The high-temperature lubricating oil can perform heat exchange with the mixture of low-temperature lubricating oil and liquid refrigerant output by the evaporator 30. Among them, the temperature of the low-temperature lubricating oil rises after heat exchange, and the temperature of the high-temperature lubricating oil drops after heat exchange. Moreover, since the cooling separator 40 is connected to the suction port 11 of the compressor 10, a low-pressure environment is formed in the cooling separator 40. At this time, under the joint action of the high-temperature lubricating oil and the low-pressure environment, the liquid refrigerant in the mixture is gasified into gaseous refrigerant in the cooling separator 40.

[0045] The medium-temperature lubricating oil separated in the cooling separator 40 is transported to the oil tank 20 for recovery. The medium-temperature lubricating oil can be transported to the oil tank 20 by an ejector, a pump or the like. Most of the gaseous refrigerant generated in the process of separating the mixture is transported to the suction port 11 of the compressor 10, and a small part of it enters the oil tank 20 along with the medium-temperature lubricating oil.

[0046] In some embodiments, the compressor 10 includes a compressor oil outlet 12, and the compressor 10 is configured to output the high-temperature lubricating oil through the compressor oil outlet 12. The oil tank 20 includes an oil tank oil inlet 21, and the oil tank oil inlet 21 is in communication with the compressor oil outlet 12.

[0047] In this way, the high-temperature lubricating oil after the bearing in the compressor 10 is output to the oil sump 20. Furthermore, the high-temperature lubricating oil can enter the cooling separator 40 to exchange heat with the mixture of low-temperature lubricating oil and liquid refrigerant. This not only ensures the lubricating effect of the lubricating oil on the bearing, but also recycles the high-temperature lubricating oil, thereby reducing costs.

[0048] Specifically, the compressor oil outlet 12 can be an interface on the compressor 10 for discharging high-temperature lubricating oil. The oil tank inlet 21 can be an interface on the oil tank 20 for receiving high-temperature lubricating oil. The compressor oil outlet 12 and the oil tank inlet 21 can be connected by pipes, hoses or other connectors to ensure smooth fluid flow.

[0049] In some embodiments, the condenser 50 includes a first gas outlet 51, the evaporator 30 includes a first fluid outlet 31, the cooling separator 40 includes a fluid inlet 41, and the air conditioning unit 100 includes a first ejector 80, which includes a first ejector inlet 81, a second ejector inlet 82, and a first ejector outlet 83. The first ejector 80 is used to eject the mixture of low-temperature lubricating oil and liquid refrigerant output from the evaporator 30 into the cooling separator 40. The first ejector inlet 81 is connected to the first gas outlet 51, the first fluid outlet 31 is connected to the second ejector inlet 82, and the first ejector outlet 83 is connected to the fluid inlet 41.

[0050] In this way, the high-pressure gas inside the condenser 50 can serve as the power source for the first ejector 80, causing the mixture of low-temperature lubricating oil and liquid refrigerant inside the evaporator 30 to be ejected into the cooling separator 40. This reduces the need for additional drive components, thereby lowering costs. Furthermore, the use of the first ejector 80 increases the flow rate of the mixture, thus improving the overall operating efficiency of the air conditioning unit 100.

[0051] During the operation of the air conditioning unit 100, most of the liquid refrigerant evaporates in the evaporator 30, but a small portion of the liquid refrigerant still mixes with the lubricating oil. In the condenser 50, most of the liquid refrigerant mixes with the lubricating oil. Therefore, connecting the first fluid outlet 31 to the second ejector inlet 82 can eject most of the lubricating oil mixed in the liquid refrigerant during the operation of the air conditioning unit 100, and can avoid ejecting excessive amounts of liquid refrigerant.

[0052] Specifically, the first gas outlet 51 is an interface on the condenser 50 for outputting high-pressure gas. The first ejector inlet 81 can be an interface on the first ejector 80 for receiving high-pressure gas output from the condenser 50. The first ejector inlet 81 and the first gas outlet 51 can be connected by a pipe, hose, or other connector.

[0053] The first fluid outlet 31 may be an interface on the evaporator 30 for discharging a mixture of cryogenic lubricating oil and liquid refrigerant. The second ejector inlet 82 may be an interface on the first ejector 80 for receiving the mixture of cryogenic lubricating oil and liquid refrigerant. The first fluid outlet 31 and the second ejector inlet 82 may be connected by a pipe, hose or other connector.

[0054] The first ejector outlet 83 is an interface on the condenser 50 used for outputting high-pressure gas. The first ejector outlet 83 can be connected to the fluid inlet 41 via a pipe, hose, or other connector.

[0055] During the operation of the air conditioning unit 100, a mixture of low-temperature lubricating oil and liquid refrigerant accumulates in the evaporator 30. The first ejector 80 is a device that uses a high-speed, high-energy flow (liquid flow, gas flow, or other material flow) to eject another low-speed, low-energy flow. By setting the first ejector 80, the low-temperature lubricating oil and liquid refrigerant can be ejected into the cooling separator 40. During the ejection process, the high-pressure gas output from the condenser 50 can serve as a power source. Under the action of the high-pressure gas output from the condenser 50, the mixture of low-temperature lubricating oil and liquid refrigerant in the evaporator 30 passes through the first ejector 80 and enters the cooling separator 40 through the fluid inlet 41.

[0056] In some embodiments, the air conditioning unit 100 further includes a first regulating valve 90, which includes a first valve inlet 91 and a first valve outlet 92. The first valve inlet 91 is connected to a first ejector outlet 83, and the first valve outlet 92 is connected to a fluid inlet 41.

[0057] Thus, the flow rate of the lubricating oil and liquid refrigerant mixture entering the cooling separator 40 can be precisely adjusted through the first regulating valve 90, thereby achieving precise control over the cooling of the high-temperature lubricating oil to the target temperature.

[0058] Specifically, the first regulating valve 90 is a control device used to regulate the fluid flow rate. By adjusting the valve opening, the first regulating valve 90 precisely controls the flow rate of the mixture of low-temperature lubricating oil and liquid refrigerant entering the cooling separator 40, thereby achieving precise regulation of the target temperature. The first regulating valve 90 can be an electric regulating valve, a pneumatic regulating valve, etc.

[0059] The first valve inlet 91 is an interface on the first regulating valve 90 for receiving fluid. The first valve inlet 91 is connected to the first ejector outlet 83 of the first ejector 80, receiving a mixture of cryogenic lubricating oil and liquid refrigerant output from the first ejector 80. The first valve inlet 91 and the first ejector outlet 83 of the first ejector 80 can be connected by a pipe, hose or other connector.

[0060] The first valve outlet 92 is the interface on the first regulating valve 90 used for discharging fluid. The first valve outlet 92 is connected to the fluid inlet 41 of the cooling separator 40, discharging the regulated mixture of low-temperature lubricating oil and liquid refrigerant to the cooling separator 40. The first valve outlet 92 and the fluid inlet 41 of the cooling separator 40 can be connected by pipes, hoses or other fittings.

[0061] In some embodiments, the cooling separator 40 includes a second gas outlet 42, which is connected to the suction port 11 of the compressor 10.

[0062] In this way, the gaseous refrigerant formed inside the cooling separator 40 can enter the compressor 10 through the second gas outlet 42 and the suction port 11 of the compressor 10, thereby realizing the circulation of refrigerant, improving the utilization rate of gaseous refrigerant, reducing refrigerant waste, and lowering the operating cost of the system.

[0063] Specifically, the second gas outlet 42 is an interface on the cooling separator 40 used for outputting gaseous refrigerant. The second gas outlet 42 and the suction port 11 of the compressor 10 can be connected via pipes, hoses or other connectors.

[0064] In some embodiments, the cooling separator 40 is provided with a first filter element 101 connected to two opposite sidewalls of the cooling separator 40. The first filter element 101 is disposed between the second gas outlet 42 and the fluid inlet 41. The first filter element 101 is used to separate the medium-temperature lubricating oil and gaseous refrigerant flowing from the fluid inlet 41 to the second gas outlet 42.

[0065] In this way, the first filter can filter the oil droplets and oil mist contained in the gaseous refrigerant, so that the filtered lubricating oil remains in the cooling separator 40 instead of entering the compressor 10 with the gaseous refrigerant. This enables efficient recovery of lubricating oil, prevents lubricating oil from entering the compressor 10 through the suction port 11 and affecting the heat exchange efficiency, and allows the compressor 10 to draw in the relatively pure gaseous refrigerant after separation.

[0066] Specifically, the first filter element 101 can be a filter screen, filter element, filter plate, etc. The cooling separator 40 can have a chamber. The first filter element 101 can isolate the chamber into two parts. The second gas outlet 42 can be located on one side of the first filter element 101, and the fluid inlet 41 can be located on the side of the first filter element 101 opposite to the second gas outlet 42. The first filter element 101 separates the medium-temperature lubricating oil and the gaseous refrigerant through filtration, ensuring the purity of the gaseous refrigerant and preventing lubricating oil from entering the compressor 10 and affecting the heat exchange efficiency.

[0067] In some embodiments, the air conditioning unit 100 includes an oil pump 102 and a heat exchanger 103. The oil pump 102 is disposed in an oil tank 20, and the heat exchanger 103 is disposed in a cooling separator 40. The oil pump 102 includes a pump outlet 1020 and is used to pump high-temperature lubricating oil into the heat exchanger 103 through the pump outlet 1020. The heat exchanger 103 includes an oil inlet 1030, which is connected to the pump outlet 1020.

[0068] Thus, the oil pump 102 allows the high-temperature lubricating oil in the oil tank 20 to be pumped into the heat exchanger 103 installed in the cooling separator 40, thereby enabling the low-temperature lubricating oil and liquid refrigerant entering the cooling separator 40 to be separated.

[0069] Specifically, oil pump 102 is a device used to transport liquid from one place to another. Oil pump 102 is installed in oil tank 20 and is used to pump high-temperature lubricating oil from oil tank 20 into heat exchanger 103. Oil pump 102 can be a centrifugal pump, gear pump, screw pump, etc.

[0070] Heat exchanger 103 is a device for exchanging heat between two fluids. Heat exchanger 103 is located within cooling separator 40 and is used to exchange heat between high-temperature lubricating oil and a mixture of low-temperature lubricating oil and liquid refrigerant within cooling separator 40. Heat exchanger 103 can be a shell-and-tube heat exchanger, which is less expensive and helps reduce the manufacturing cost of air conditioning unit 100.

[0071] The heat exchanger inlet 1030 can be an interface on the heat exchanger 103 for receiving high-temperature lubricating oil. The pump outlet 1020 can be an interface on the oil pump 102 for discharging high-temperature lubricating oil. The heat exchanger inlet 1030 and the pump outlet 1020 can be connected by pipes, hoses or other connectors.

[0072] The high-temperature lubricating oil exchanges heat with a mixture of low-temperature lubricating oil and liquid refrigerant located in the cooling separator 40 within the heat exchanger 103. The heat from the high-temperature lubricating oil is transferred to the mixture, causing the liquid refrigerant in the mixture to vaporize into gaseous refrigerant. Simultaneously, the temperature of the high-temperature lubricating oil decreases, while the temperature of the low-temperature lubricating oil increases, becoming medium-temperature lubricating oil. Since the low-temperature lubricating oil and liquid refrigerant are not separated within the oil tank 20, the lubricating oil in the oil tank 20 will not experience an increase in refrigerant solubility due to a temperature drop. This prevents a decrease in lubricating oil viscosity, thus avoiding flashing of liquid refrigerant at the lubricating oil pump inlet and causing unstable oil supply, thereby preventing the air conditioning unit 100 from triggering an alarm and shutting down.

[0073] In some embodiments, the heat exchanger 103 further includes an exchanger oil outlet 1031, and the compressor 10 includes a compressor oil inlet 13, which is used to receive high-temperature lubricating oil after heat exchange with low-temperature lubricating oil and liquid refrigerant. The exchanger oil outlet 1031 is connected to the compressor oil inlet 13.

[0074] In this way, the temperature of the high-temperature lubricating oil after heat exchange is lower. The lower-temperature lubricating oil is output to the compressor 10 through the heat exchanger 103, which can lubricate the bearings inside the compressor 10 and ensure the stable operation of the compressor 10.

[0075] Specifically, the compressor oil inlet 13 is the interface on the compressor 10 for receiving high-temperature lubricating oil after heat exchange with low-temperature lubricating oil and liquid refrigerant. The heat exchanger oil outlet 1031 is the interface on the heat exchanger 103 for discharging high-temperature lubricating oil after heat exchange with low-temperature lubricating oil and liquid refrigerant. After heat exchange, the high-temperature lubricating oil cools down and enters the compressor 10 through the compressor oil inlet 13, effectively lubricating the bearings inside the compressor 10. The compressor oil inlet 13 and the heat exchanger oil outlet 1031 can be connected by pipes, hoses, or other connectors.

[0076] In some embodiments, the air conditioning unit 100 further includes a second ejector 104, which includes a third ejector inlet 1040, a fourth ejector inlet 1041, and a second ejector outlet 1042. The second ejector 104 is used to eject the medium-temperature lubricating oil and part of the gaseous refrigerant in the cooling separator 40 into the oil tank 20 under the action of the high-pressure gas output from the condenser 50. The condenser 50 includes a second gas outlet 52, the cooling separator 40 includes a second fluid outlet 43, and the oil tank 20 includes an oil tank fluid inlet 22. The second gas outlet 52 is connected to the third ejector inlet 1040, the second fluid outlet 43 is connected to the fourth ejector inlet 1041, and the second ejector outlet 1042 is connected to the oil tank fluid inlet 22.

[0077] In this way, the high-pressure gas inside the condenser 50 can serve as the power source for the second ejector 104, allowing the medium-temperature lubricating oil and a portion of the gaseous refrigerant to be ejected into the oil tank 20. This reduces the need for additional drive components, thereby lowering costs. Furthermore, the use of the second ejector 104 increases the flow velocity of the mixture, thus improving the overall operating efficiency of the air conditioning unit 100.

[0078] Specifically, the third ejector inlet 1040 is the interface on the second ejector 104 for receiving the high-pressure gas output from the condenser 50. The fourth ejector inlet 1041 is the interface on the second ejector 104 for receiving the medium-temperature lubricating oil and part of the gaseous refrigerant inside the cooling separator 40. The second ejector outlet 1042 is the interface on the second ejector 104 for outputting the ejected medium-temperature lubricating oil and part of the gaseous refrigerant. The second gas outlet 52 is the interface on the condenser 50 for outputting the high-pressure gas. The second fluid outlet 43 is the interface on the cooling separator 40 for outputting the medium-temperature lubricating oil and part of the gaseous refrigerant.

[0079] The third ejector inlet 1040 and the second gas outlet 52 can be connected by a pipe, hose, or other connector. The fourth ejector inlet 1041 and the second fluid outlet 43 can be connected by a pipe, hose, or other connector. The oil tank fluid inlet 22 and the second ejector outlet 1042 can be connected by a pipe, hose, or other connector.

[0080] After the gaseous refrigerant separates from the low-temperature lubricating oil, most of the gaseous refrigerant flows through the second gas outlet 42 of the cooling separator 40 to the suction port 11 of the compressor 10, where it is received and compressed. The remaining gaseous refrigerant follows the medium-temperature lubricating oil into the second ejector 104 and further into the oil sump 20.

[0081] The second ejector 104 is a device that uses a high-speed, high-energy flow (liquid flow, gas flow, or other material flow) to eject another low-speed, low-energy flow. The second fluid outlet 43 can be located at the bottom of the cooling separator 40 to completely drain the lubricating oil accumulated within it. By installing the second ejector 104, medium-temperature lubricating oil and a portion of the gaseous refrigerant can be ejected into the oil tank 20. During the ejection process, the high-pressure gas output from the condenser 50 can serve as a power source. Under the influence of the high-pressure gas output from the condenser 50, the medium-temperature lubricating oil and a portion of the gaseous refrigerant pass through the second ejector 104 and enter the oil tank 20 through the oil tank fluid inlet 22.

[0082] In some embodiments, the oil tank 20 includes an oil tank outlet 23, through which the oil tank 20 supplies gaseous refrigerant to the compressor 10, and the oil tank outlet 23 is connected to the suction port 11 of the compressor 10.

[0083] In this way, the gaseous refrigerant that follows the medium-temperature lubricating oil from the cooling separator 40 into the oil tank 20 can enter the compression molding machine through the oil tank outlet 23 and the compressor 10 suction port 11, thereby realizing the circulation of refrigerant, improving the utilization rate of gaseous refrigerant, reducing refrigerant waste, and lowering the operating cost of the system.

[0084] Specifically, the oil tank outlet 23 is an interface on the oil tank 20 for outputting gaseous refrigerant. Through the oil tank outlet 23, a small portion of the gaseous refrigerant ejected into the oil tank 20 via the second ejector 104 can enter the suction port 11 of the compressor 10. The oil tank outlet 23 and the suction port 11 of the compressor 10 can be connected via pipes, hoses, or other connectors.

[0085] In some embodiments, the oil tank 20 is provided with a second filter element 105 connected to two opposite side walls of the oil tank 20. The second filter element 105 is disposed between the oil tank outlet 23 and the oil tank fluid inlet 22. The second filter element 105 is used to separate the lubricating oil and gaseous refrigerant flowing from the oil tank fluid inlet 22 to the oil tank outlet 23.

[0086] In this way, the second filter can filter the oil droplets and oil mist contained in the gaseous refrigerant, so that the filtered lubricating oil remains in the oil tank 20 instead of entering the compressor 10 with the gaseous refrigerant. This enables efficient recovery of lubricating oil, prevents lubricating oil from entering the compressor 10 through the suction port 11 and affecting the heat exchange efficiency, and allows the compressor 10 to draw in the relatively pure gaseous refrigerant after separation.

[0087] Specifically, the second filter element 105 can be a filter screen, filter element, filter plate, etc. The oil tank 20 can have a chamber. The second filter element 105 can divide the chamber into two parts. The oil tank fluid inlet 22 can be located on one side of the second filter element 105, and the oil tank outlet 23 can be located on the side of the second filter element 105 away from the oil tank fluid inlet 22. Through filtration, the second filter element 105 separates the lubricating oil and gaseous refrigerant in the oil tank 20, ensuring the purity of the gaseous refrigerant and preventing lubricating oil from entering the compressor 10 and affecting the heat exchange efficiency.

[0088] In some embodiments, the air conditioning unit 100 further includes a second regulating valve 106, which includes a second valve inlet 1060 and a second valve outlet 1061. The second valve inlet 1060 is connected to the second ejector outlet 1042, and the second valve outlet 1061 is connected to the oil tank fluid inlet 22.

[0089] Thus, the flow rate of medium-temperature lubricating oil and gaseous refrigerant entering the oil tank 20 can be precisely adjusted through the second regulating valve 106, thereby maintaining the temperature of the lubricating oil in the oil tank 20.

[0090] Specifically, the second regulating valve 106 is a control device used to regulate fluid flow. By adjusting the valve opening, the second regulating valve 106 precisely controls the flow rate of the medium-temperature lubricating oil and gaseous refrigerant entering the oil tank 20, thereby achieving precise regulation of the target temperature. The second regulating valve 106 can be an electric regulating valve, a pneumatic regulating valve, etc.

[0091] The second valve inlet 1060 is an interface on the second regulating valve 106 used to receive fluid. The second valve inlet 1060 is connected to the second ejector outlet 1042 of the second ejector 104, receiving the medium-temperature lubricating oil and gaseous refrigerant output from the second ejector 104. The second valve inlet 1060 and the second ejector outlet 1042 of the second ejector 104 can be connected by a pipe, hose or other connector.

[0092] The second valve outlet 1061 is the interface on the second regulating valve 106 used for fluid output. The second valve outlet 1061 is connected to the oil tank fluid inlet 22 of the oil tank 20, outputting the regulated medium-temperature lubricating oil and gaseous refrigerant to the oil tank 20 to complete lubricating oil recovery. The second valve outlet 1061 and the oil tank fluid inlet 22 of the oil tank 20 can be connected via pipes, hoses, or other connectors.

[0093] In some embodiments, the air conditioning unit 100 further includes an oil heater 107 disposed in the oil tank 20 for heating the lubricating oil in the oil tank 20. By providing the oil heater 107, the medium-temperature lubricating oil entering the oil tank 20 from the cooling separator 40 can be heated to prevent the oil temperature in the oil tank 20 from being too low.

[0094] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0095] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An air conditioning unit, characterized in that, The air conditioning unit includes: compressor; An oil tank, which is connected to the compressor, is used to receive high-temperature lubricating oil output by the compressor; Evaporator; A cooling separator is connected to both the oil tank and the evaporator. It is used to separate the mixture of low-temperature lubricating oil and liquid refrigerant output from the evaporator and to receive the high-temperature lubricating oil, so that the mixture of low-temperature lubricating oil and liquid refrigerant can exchange heat with the high-temperature lubricating oil to obtain medium-temperature lubricating oil. The cooling separator is also connected to the suction port of the compressor to vaporize the liquid refrigerant into gaseous refrigerant. The oil tank is also used to receive the medium-temperature lubricating oil; The compressor is used to receive and compress the gaseous refrigerant.

2. The air conditioning unit according to claim 1, characterized in that, The compressor includes a compressor oil outlet, which is used to output the high-temperature lubricating oil. The oil tank includes an oil tank inlet, which is connected to the compressor oil outlet.

3. The air conditioning unit according to claim 1, characterized in that, The air conditioning unit further includes a condenser, which includes a first gas outlet; an evaporator, which includes a first fluid outlet; a cooling separator, which includes a fluid inlet; and a first ejector, which includes a first ejector inlet, a second ejector inlet, and a first ejector outlet. The first ejector is used to eject a mixture of low-temperature lubricating oil and liquid refrigerant output from the evaporator into the cooling separator. The first ejector inlet is connected to the first gas outlet, the first fluid outlet is connected to the second ejector inlet, and the first ejector outlet is connected to the fluid inlet.

4. The air conditioning unit according to claim 3, characterized in that, The air conditioning unit further includes a first regulating valve, which includes a first valve inlet and a first valve outlet. The first valve inlet is connected to the first ejector outlet, and the first valve outlet is connected to the fluid inlet.

5. The air conditioning unit according to claim 3, characterized in that, The cooling separator includes a second gas outlet, which is connected to the suction port of the compressor.

6. The air conditioning unit according to claim 5, characterized in that, The cooling separator is provided with a first filter element connected to two opposite side walls of the cooling separator. The first filter element is disposed between the second gas outlet and the fluid inlet. The first filter element is used to separate the medium-temperature lubricating oil and gaseous refrigerant flowing from the fluid inlet to the second gas outlet.

7. The air conditioning unit according to claim 1, characterized in that, The air conditioning unit includes an oil pump and a heat exchanger. The oil pump is disposed in the oil tank, and the heat exchanger is disposed in the cooling separator. The oil pump includes a pump outlet and is used to pump the high-temperature lubricating oil into the heat exchanger through the pump outlet. The heat exchanger includes an oil inlet and the oil inlet is connected to the pump outlet.

8. The air conditioning unit according to claim 7, characterized in that, The heat exchanger also includes an oil outlet, and the compressor includes an oil inlet. The oil inlet is used to receive the high-temperature lubricating oil after heat exchange with the low-temperature lubricating oil and the liquid refrigerant. The oil outlet is connected to the oil inlet.

9. The air conditioning unit according to claim 1, characterized in that, The air conditioning unit further includes a condenser and a second ejector. The second ejector includes a third ejector inlet, a fourth ejector inlet, and a second ejector outlet. The second ejector is used to eject the medium-temperature lubricating oil and part of the gaseous refrigerant in the cooling separator into the oil tank under the action of the high-pressure gas output from the condenser. The condenser includes a second gas outlet, the cooling separator includes a second fluid outlet, and the oil tank includes an oil tank fluid inlet. The second gas outlet is connected to the third ejector inlet, the second fluid outlet is connected to the fourth ejector inlet, and the second ejector outlet is connected to the oil tank fluid inlet.

10. The air conditioning unit according to claim 9, characterized in that, The oil tank includes an oil tank outlet, through which the oil tank supplies the gaseous refrigerant to the compressor, and the oil tank outlet is connected to the compressor's suction port.

11. The air conditioning unit according to claim 10, characterized in that, The oil tank is provided with a second filter element connected to two opposite side walls of the oil tank. The second filter element is located between the air outlet of the oil tank and the fluid inlet of the oil tank. The second filter element is used to separate the lubricating oil and gaseous refrigerant flowing from the fluid inlet of the oil tank to the air outlet of the oil tank.

12. The air conditioning unit according to claim 9, characterized in that, The air conditioning unit also includes a second regulating valve, which includes a second valve inlet and a second valve outlet. The second valve inlet is connected to the second ejector outlet, and the second valve outlet is connected to the oil tank fluid inlet.

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