Refrigeration system

Abstract

The utility model discloses a refrigerating system, through connecting multiple parallel fluidic devices between pump body and compressor, pump body receives the liquid refrigerant and lubricating oil from evaporator and pumps it out from the export of pump body, enters the entrance of fluidic device through first pipeline, and refrigerant is gasified through fluidic device, thereby separating refrigerant and lubricating oil, and fluidic device can transport separated lubricating oil and refrigerant back to compressor. Electromagnetic valve is equipped on first pipeline, and detection module for detecting the oil volume of lubricating oil in compressor is arranged in compressor, and control device is electrically connected with electromagnetic valve and detection module, thereby controlling the number of electromagnetic valve starting according to the oil volume of lubricating oil in compressor detected by detection device. In this way, the oil volume condition of lubricating oil in compressor can be monitored through detection module, and the number of electromagnetic valve starting is dynamically adjusted according to the detection result of detection module by control device, thereby controlling the oil return volume of compressor and improving the flexibility of compressor oil return.

Description

Technical Field

[0001] This application relates to the field of refrigeration equipment technology, and more particularly to a refrigeration system. Background Technology

[0002] In refrigeration systems, lubricating oil plays a crucial role in ensuring the normal operation of the compressor and extending the service life of the equipment. Taking a household refrigerator as an example, in the high-temperature range of the refrigeration system, typically between 2-8°C, the refrigeration oil and refrigerant are miscible. However, at low temperatures, typically below -16°C, due to decreased solubility, the refrigeration oil precipitates from the refrigerant. If this precipitated oil cannot be returned to the compressor, over time it will lead to oil shortage in the compressor unit and oil accumulation in the evaporator, resulting in reduced refrigeration efficiency. Therefore, an oil return device is required in the refrigeration system.

[0003] In related technologies, oil return devices can only continuously return oil, making it difficult to control the amount of lubricating oil returning to the compressor. This makes it difficult to maintain the amount of lubricating oil inside the compressor within a stable and reasonable range. If too much oil is returned, the compressor will malfunction due to "liquid slugging" of the lubricating oil. If the oil return is insufficient, it will lead to a lack of oil inside the compressor, affecting its normal operation. Utility Model Content

[0004] This utility model discloses a refrigeration system that can control the amount of oil returned by the compressor.

[0005] To achieve the above objectives, the first aspect of this utility model discloses a refrigeration system, comprising:

[0006] Evaporator;

[0007] A pump body, with pipes connected to the evaporator, is configured to receive liquid refrigerant and lubricating oil from the evaporator and pump them out from the outlet of the pump body;

[0008] A compressor configured to compress the refrigerant in a low-pressure gaseous state into the refrigerant in a high-pressure gaseous state, the compressor having a detection module for detecting the amount of lubricating oil in the compressor;

[0009] Multiple ejectors are connected in parallel. The inlet of each ejector is connected to the outlet of the pump body via a first pipeline to deliver the liquid refrigerant and the lubricating oil to the ejector through the first pipeline. The ejector is configured to vaporize the refrigerant to separate the refrigerant and the lubricating oil. The outlet pipeline of the ejector is connected to the inlet of the compressor to return the separated lubricating oil and refrigerant to the compressor. A solenoid valve is provided on the first pipeline to control the opening and closing of the first pipeline and the inlet of the ejector.

[0010] A control device is electrically connected to the detection module and the solenoid valve. The control device is used to control the number of solenoid valves to be activated based on the amount of lubricating oil in the compressor detected by the detection device.

[0011] As an optional implementation, the ejector includes a nozzle, a suction chamber, and a diffuser. The suction chamber includes a first end and a second end along the flow direction, and the diffuser includes a third end and a fourth end along the flow direction. The second end and the third end are connected. The inlet of the nozzle is connected to the outlet of the compressor, and the outlet of the nozzle is located at the connection between the second end and the third end, so that the nozzle is connected to both the suction chamber and the diffuser. The nozzle is configured to inject high-pressure liquid refrigerant and lubricating oil into the connection between the second end and the third end to create a low-pressure zone in the suction chamber, thereby drawing the liquid refrigerant and lubricating oil in the first pipeline into the low-pressure zone. The cross-sectional area of ​​the suction chamber, perpendicular to the flow direction, gradually decreases from the first end to the second end to vaporize the refrigerant. The cross-sectional area of ​​the diffuser, perpendicular to the flow direction, gradually increases from the third end to the fourth end to reduce the flow rate of the refrigerant and the lubricating oil.

[0012] As an optional implementation, the refrigeration system further includes a heat exchanger having a first inlet and a first outlet disposed opposite to each other, the first inlet and the first outlet being connected by a second pipeline, the first inlet being configured to be connected to the outlet of the ejector, the first outlet being configured to be connected to the inlet of the compressor, the heat exchanger being configured to introduce a heat exchange medium to exchange heat with the refrigerant and the lubricating oil in the second pipeline to vaporize the refrigerant, and the heat exchanger being further configured to send the separated lubricating oil to the compressor.

[0013] As an optional implementation, the heat exchanger includes a fifth end and a sixth end opposite to each other along the flow direction, the first inlet is disposed at the fifth end and is disposed near the top of the fifth end, and the first outlet is disposed at the sixth end and is disposed near the bottom of the sixth end.

[0014] As an optional implementation, the first outlet of the heat exchanger is connected to an oil storage pipe, which is connected to the inlet of the compressor via the oil storage pipe. The oil storage pipe is configured to store the lubricating oil and allow the refrigerant to pass through to enter the compressor.

[0015] As an optional implementation, the oil storage pipe is a U-shaped pipe, including a third pipe, an oil storage section and a fourth pipe connected in sequence. The third pipe is connected to the first outlet, the fourth pipe is connected to the inlet of the compressor, and the oil storage section is configured to store the lubricating oil.

[0016] As an optional implementation, the refrigeration system further includes a liquid storage tank, and the heat exchanger further includes a second inlet and a second outlet disposed opposite to each other. The second inlet is disposed at the sixth end and is spaced apart from the first outlet. The second outlet is disposed at the fifth end and is spaced apart from the first inlet. The second inlet and the second outlet are connected through a fifth pipeline. The liquid storage tank is connected to both the outlet of the compressor and the second inlet. The liquid storage tank is configured to store the high-temperature liquid refrigerant and the lubricating oil delivered by the compressor, and to deliver the high-temperature liquid refrigerant and the lubricating oil to the fifth pipeline for heat exchange.

[0017] As an optional implementation, the second outlet is connected to the pump body via a pipeline, so that the heat exchanger can deliver the refrigerant and the lubricating oil after heat exchange in the fifth pipeline into the pump body.

[0018] As an optional implementation, the refrigeration system further includes a low-pressure circulation tank, which is connected by pipelines to the evaporator, the pump body, the second outlet, and the compressor. The low-pressure circulation tank is used to perform gas-liquid separation on the gas-liquid mixture of refrigerant and lubricating oil transported by the fifth pipeline and the evaporator, so that the separated gaseous refrigerant is transported to the compressor through the pipeline, and the separated liquid refrigerant and lubricating oil are transported to the pump body through the pipeline. The outlet of the pump body is connected to the inlet of the evaporator through a pipeline, so that the liquid refrigerant and lubricating oil are transported to the evaporator through the pipeline.

[0019] As an optional implementation, the first pipeline is further provided with a filter device, which is located near the pump body relative to the solenoid valve, and the filter device is configured to filter the refrigerant and the lubricating oil.

[0020] Compared with the prior art, the beneficial effects of this application are:

[0021] This utility model provides a refrigeration system that connects multiple parallel ejectors between a pump body and a compressor. The pump body receives liquid refrigerant and lubricating oil from the evaporator and pumps it out from the pump body outlet. The liquid refrigerant and lubricating oil enter the inlet of the ejector through a first pipeline. The ejector vaporizes the refrigerant, thus separating the refrigerant and lubricating oil. The ejector also returns the separated lubricating oil and refrigerant to the compressor. Simultaneously, a solenoid valve is installed on the first pipeline, and a detection module for detecting the amount of lubricating oil in the compressor is installed inside the compressor. A control device is electrically connected to both the solenoid valve and the detection module, thereby controlling the number of solenoid valves activated based on the amount of lubricating oil detected by the detection device. This allows the detection module to monitor the amount of lubricating oil in the compressor in real time, and the control device can dynamically adjust the number of activated solenoid valves based on the detection results, thereby controlling the flow rate of liquid refrigerant and lubricating oil entering the ejector, and ultimately controlling the amount of oil returned to the compressor, improving the flexibility of oil return and ensuring continuous operation of the compressor. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the refrigeration system disclosed in the embodiments of this application;

[0024] Figure 2 This is a schematic diagram of the jet ejector disclosed in the embodiments of this application;

[0025] Figure 3 yes Figure 1 A magnified view of a section at point A in the middle;

[0026] Figure 4 This is a schematic diagram of the lubricating oil not covering the oil reservoir as disclosed in the embodiments of this application;

[0027] Figure 5 This is a schematic diagram of lubricating oil covering the oil reservoir as disclosed in the embodiments of this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 100-Refrigeration system; 1-Evaporator; 2-Pump body; 3-Compressor; 4-Ejector; 41-Nozzle; 411-First pipeline; 411a-Solenoid valve; 411b-Filter device; 42-Suction chamber; 421-First end; 422-Second end; 423-Low-pressure zone; 43-Diffuser; 431-Third end; 432-Fourth end; 5-Heat exchanger; 51-Fifth end; 511-First inlet; 511a-Second pipeline; 512-Second outlet; 512a-Fifth pipeline; 52-Sixth end; 521-First outlet; 522-Second inlet; 522a-Liquid storage tank; 6-Oil storage pipe; 61-Third pipeline; 62-Oil storage section; 63-Fourth pipeline; 7-Low-pressure circulation tank; 8-Condenser. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] In this application, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated equipment, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0032] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0033] Furthermore, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection via an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0034] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0035] A refrigeration system is a thermodynamic system that transfers heat through the phase change cycle of a refrigerant. It mainly consists of four core components: a compressor, a condenser, a throttling valve, and an evaporator. The refrigeration cycle is completed through four basic processes: compression, condensation, throttling, and evaporation. The compressor primarily compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gas, providing the power for the refrigeration system's cycle. The condenser condenses the high-temperature, high-pressure gas into a high-pressure, room-temperature liquid through heat exchange. The throttling valve reduces the liquid pressure and temperature, controlling the refrigerant flow rate. The low-temperature, low-pressure liquid refrigerant absorbs heat and evaporates in the evaporator, thus lowering the ambient temperature.

[0036] The compressor is a crucial component of the refrigeration system, providing power for the refrigeration cycle. During compressor operation, lubricating oil plays multiple key roles. For example, it forms an oil film between moving parts such as the piston and cylinder, and the rotor meshing surfaces, reducing friction and wear and extending equipment life. It also absorbs heat generated during compression and friction, carrying it away through circulation to control the overall compressor temperature and prevent overheating and deformation of compressor components. Furthermore, it forms an oil film seal at locations such as the cylinder and piston, and the scroll plate clearance, reducing leakage of high-pressure refrigerant inside the compressor and thus improving compression efficiency. During compressor operation, refrigerant and lubricating oil become miscible at high temperatures, causing lubricating oil to flow out of the compressor along with the refrigerant gas. If this lost lubricating oil cannot be returned to the compressor, over time, this can lead to insufficient oil in the compressor and oil accumulation in the evaporator, resulting in reduced refrigeration efficiency. Therefore, an oil return device is necessary in the refrigeration system.

[0037] In related technologies, oil return devices can only continuously return oil, making it difficult to control the amount of lubricating oil returning to the compressor. This makes it difficult to maintain the amount of lubricating oil inside the compressor within a stable and reasonable range. If too much oil is returned, the compressor will malfunction due to "liquid slugging" of the lubricating oil. If the oil return is insufficient, it will lead to a lack of oil inside the compressor, affecting its normal operation.

[0038] In view of this, this application discloses a refrigeration system. A pump body pipe is connected to an evaporator to receive liquid refrigerant and lubricating oil from the evaporator and transport them to ejectors through a first pipeline. A compressor is used to compress low-pressure gaseous refrigerant into high-pressure gaseous refrigerant, and its internal component is equipped with a detection module for detecting the amount of lubricating oil inside the compressor. Multiple ejectors connected in parallel are used to vaporize the refrigerant to separate the refrigerant and lubricating oil. The ejector outlet is connected to the compressor inlet to return the separated lubricating oil and refrigerant to the compressor. A solenoid valve is installed on the first pipeline. A control device is electrically connected to both the detection module and the solenoid valve to control the number of solenoid valves activated based on the detection results of the detection device. This allows the detection module inside the compressor to detect the amount of lubricating oil, and the control device can control the number of solenoid valves activated based on the amount of oil. For example, when the amount of oil inside the compressor is low, multiple ejectors can be activated to increase the flow rate of refrigerant and lubricating oil entering the ejectors for gas-liquid separation, thereby increasing the amount of oil returned to the compressor. When there is a large amount of oil inside the compressor, the number of ejectors that can be opened can be reduced, thus decreasing the amount of oil returning to the compressor. This improves the flexibility of oil return in the compressor, preventing insufficient or excessive oil return, and ensuring the continuous operation of the compressor.

[0039] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.

[0040] Please see Figure 1 , Figure 1This is a schematic diagram of the refrigeration system disclosed in this application. Solid lines in the diagram represent pipes connecting various components, and arrows indicate the flow direction of refrigerant and lubricating oil. The refrigeration system 100 includes an evaporator 1, a pump body 2, a compressor 3, multiple ejectors 4, and a control device (not shown). The pump body 2 is piped to the evaporator 1 and is configured to receive liquid refrigerant and lubricating oil from the evaporator 1 and pump them out from the outlet of the pump body 2. The compressor 3 is configured to compress low-pressure gaseous refrigerant into high-pressure gaseous refrigerant. The compressor 3 includes a detection module (not shown) for detecting the amount of lubricating oil within the compressor 3. Multiple ejectors 4 are arranged in parallel. The inlet of each ejector 4 is connected to the outlet of the pump body 2 via a first pipe 411 to deliver liquid refrigerant and lubricating oil to the ejectors 4 through the first pipe 411. The ejectors 4 are configured to vaporize the refrigerant to separate the refrigerant and lubricating oil. The outlet pipe of the ejector 4 is connected to the inlet of the compressor 3 to return the separated lubricating oil and refrigerant to the compressor 3. A solenoid valve 411a is installed on the first pipe 411, which controls the opening and closing of the first pipe 411 and the inlet of the ejector 4. The control device is electrically connected to the detection module and the solenoid valve 411a. The control device controls the number of solenoid valves 411a activated based on the amount of lubricating oil detected by the detection device within the compressor 3.

[0041] The refrigeration system 100 disclosed in this application can detect the amount of lubricating oil in the compressor 3 in real time by installing a detection module inside the compressor 3. When the amount of oil in the compressor 3 is insufficient, the control device can control the opening degree of the solenoid valve 411a according to the detection result of the detection module, adjusting the amount of liquid refrigerant and lubricating oil delivered from the pump body 2 to the ejector 4, thereby controlling the amount of lubricating oil separated and returned to the compressor 3 by the ejector 4. This avoids problems such as compressor 3 wear due to insufficient lubricating oil or liquid slugging caused by excessive oil return, thus ensuring the stable operation of the compressor 3.

[0042] It is understood that the evaporator 1 mentioned above can be an air-cooled evaporator 1 or a water-cooled evaporator 1, etc., and this embodiment does not make specific limitations on this.

[0043] It is understood that the pump body 2 mentioned above can be a gear pump or a vane pump, etc., and this embodiment does not make specific limitations on it.

[0044] It is understood that the aforementioned detection module can be a liquid level sensor or a pressure sensor, etc., and this embodiment does not specifically limit it. The pressure sensor indirectly determines the amount of lubricating oil by utilizing the pressure change of the lubricating oil inside the compressor 3. For example, the lubricating oil creates a certain pressure inside the compressor 3; when the amount of oil inside the compressor 3 decreases, the pressure will decrease accordingly. The control device can determine whether the amount of lubricating oil is normal based on the magnitude of the pressure signal.

[0045] It is understood that the aforementioned control device may be a programmable logic controller, a microcontroller, or a microprocessor, etc., and this embodiment does not specifically limit it.

[0046] It is understood that the solenoid valve 411a mentioned above can be a ball valve type solenoid valve 411a or a piston type solenoid valve 411a, etc., and this embodiment does not make specific limitations on it.

[0047] It is understood that the refrigerant can be a Freon-like substance (such as R134a, R410A, R22, etc.) or ammonia, etc., and can be selected according to actual usage requirements. This embodiment does not make specific limitations in this regard.

[0048] It is understood that the lubricating oil can be mineral oil, synthetic oil, or alkylbenzene oil, etc., and the specific choice can be made according to actual usage requirements. This embodiment does not make any specific limitations on this.

[0049] It is understandable that the parallel arrangement of multiple ejectors 4 means that the inlet of each ejector 4 is connected to a first pipe 411, and the multiple first pipes 411 are connected to a main pipe and then to the outlet of the pump body 2. Each first pipe 411 is equipped with a solenoid valve 411a. The outlet of each ejector 4 is also connected to a pipe, and the multiple pipes are then connected to a main pipe and then to the inlet of the compressor 3.

[0050] For example, such as Figure 1 As shown, there are two ejectors 4 and two corresponding solenoid valves 411a. Each solenoid valve 411a controls the opening and closing of the inlet of the ejector 4 and the first pipeline 411, which are installed on the same pipeline.

[0051] Please see Figure 1 and Figure 2 , Figure 2 This is a schematic diagram of the jet ejector disclosed in an embodiment of this application. Figure 2The dashed box indicates the approximate location of the low-pressure zone 423. In some embodiments, the ejector 4 includes a nozzle 41, a suction chamber 42, and a diffuser 43. The suction chamber 42 includes a first end 421 and a second end 422 along the flow direction, and the diffuser 43 includes a third end 431 and a fourth end 432 along the flow direction. The second end 422 and the third end 431 are connected. The inlet of the nozzle 41 is connected to the outlet of the compressor 3, and the outlet of the nozzle 41 is located at the connection between the second end 422 and the third end 431, so that the nozzle 41 is connected to both the suction chamber 42 and the diffuser 43. The nozzle 41 is configured to inject high-pressure liquid refrigerant and lubricating oil into the connection between the second end 422 and the third end 431 to create a low-pressure zone 423 in the suction chamber 42, thereby drawing the liquid refrigerant and lubricating oil in the first pipeline 411 into the low-pressure zone 423. The cross-sectional area of ​​the suction chamber 42, perpendicular to the flow direction, gradually decreases from the first end 421 to the second end 422 to vaporize the refrigerant. The cross-sectional area of ​​the diffuser 43, perpendicular to the flow direction, gradually increases from the third end 431 to the fourth end 432 to reduce the flow rate of the refrigerant and lubricating oil.

[0052] High-pressure liquid refrigerant and lubricating oil from the compressor 3 outlet are injected at high speed through nozzle 41 of ejector 4 into the connection between suction chamber 42 and diffuser pipe 43. Utilizing the Venturi effect, a low-pressure zone 423 is formed, thereby drawing the refrigerant and lubricating oil from the first pipe into suction chamber 42. Simultaneously, the gradually decreasing cross-sectional area of ​​suction chamber 42 along the flow direction (i.e., gradually decreasing from the first end 421 to the second end 422) gradually reduces the pressure of the liquid refrigerant. This pressure reduction lowers the refrigerant's saturation temperature, making it easier for the refrigerant to reach saturation and vaporize. Since the boiling point of lubricating oil is much higher than that of refrigerant, the lubricating oil remains liquid during vaporization, thus achieving separation between the lubricating oil and refrigerant. The separated lubricating oil is decelerated and pressurized through diffuser pipe 43 before flowing back to compressor 3, effectively maintaining lubrication inside compressor 3 and ensuring its normal operation. The ejector 4 adopts an integrated design of nozzle 41, suction chamber 42 and diffuser 43, which eliminates the need for additional oil separators or complex piping, thereby simplifying the structure of the entire refrigeration system 100.

[0053] Furthermore, by connecting the inlet of nozzle 41 to the outlet of compressor 3, the high-pressure liquid refrigerant and lubricating oil discharged from compressor 3 can be sprayed through nozzle 41 into the connection between the second end 422 and the third end 431, creating a low-pressure zone 423. This allows the liquid refrigerant and lubricating oil in the first pipeline 411 to be drawn into the low-pressure zone 423. This effectively utilizes the high-pressure refrigerant and lubricating oil at the outlet of compressor 3, providing the power to draw the liquid refrigerant and lubricating oil in the first pipeline 411 into the ejector 4, eliminating the need for an additional power source.

[0054] Secondly, the cross-sectional area of ​​the suction chamber 42 along the direction perpendicular to the flow gradually decreases from the first end 421 to the second end 422, and the outlet of the nozzle 41 is located at the connection between the second end 422 and the third end 431, and is connected to both the suction chamber 42 and the diffuser pipe 43. In this way, when the liquid refrigerant and lubricating oil in the first pipeline 411 are drawn to the low-pressure zone 423, the refrigerant will rapidly vaporize due to the sudden drop in pressure during the process of flowing from the first end 421 to the second end 422, thereby achieving the separation of refrigerant and lubricating oil.

[0055] As can be seen, in the ejector 4 of this application, the nozzle 41 can integrate the functions of separation and oil return, thereby simplifying the structure of the entire refrigeration system 100.

[0056] It is understood that the nozzle 41 mentioned above can be a venturi nozzle or an axial flow nozzle, etc., and this embodiment does not specifically limit it.

[0057] It is understood that the aforementioned inhalation chamber 42 and diffuser tube 43 can be similar to a venturi tube, with a narrow throat in the middle and a converging tube and a diverging tube on both sides, respectively. Alternatively, the inhalation chamber 42 can be a converging conical tube and the diffuser tube 43 can be a diverging conical tube; this embodiment does not specifically limit this.

[0058] It is understood that the nozzle 41, suction chamber 42 and diffuser tube 43 may be integrally formed or manufactured separately and then connected together. This embodiment does not make specific limitations on this.

[0059] As the liquid refrigerant and lubricating oil first pass through the suction chamber 42, the cross-sectional area and pressure gradually decrease, resulting in a lower saturation temperature and causing the liquid refrigerant to vaporize. However, after the vaporized refrigerant enters the diffuser 43, the pressure gradually increases, causing the saturation temperature to rise, which in turn causes some of the vaporized refrigerant to re-liquefy. Therefore, to vaporize more liquid refrigerant and improve the separation effect between the refrigerant and lubricating oil, please refer to [the relevant documentation / reference needed]. Figure 1 and Figure 3 , Figure 3 yes Figure 1 A partial enlarged view at point A. In some embodiments, the refrigeration system 100 further includes a heat exchanger 5, which includes a first inlet 511 and a first outlet 521 disposed opposite to each other. The first inlet 511 and the first outlet 521 are connected by a second pipe 511a. The first inlet 511 is configured to communicate with the outlet of the ejector 4, and the first outlet 521 is configured to communicate with the inlet of the compressor 3. The heat exchanger 5 is configured to introduce a heat exchange medium to exchange heat with the refrigerant and lubricating oil in the second pipe 511a, so as to vaporize the refrigerant. The heat exchanger 5 is also configured to send the separated lubricating oil to the compressor 3.

[0060] By connecting the heat exchanger 5 to the outlet of the ejector 4, the heat exchange medium introduced into the heat exchanger 5 can exchange heat with the refrigerant and lubricating oil in the second pipeline 511a, so that the unvaporized refrigerant in the ejector 4 can be completely vaporized, thereby improving the separation efficiency of refrigerant and lubricating oil.

[0061] In addition, heat exchanger 5 heats the lubricating oil while vaporizing the refrigerant. The increased temperature of the lubricating oil reduces its viscosity, allowing it to flow more smoothly in the pipeline. This reduces flow resistance and the risk of pipeline blockage caused by excessively high lubricating oil viscosity, enabling the lubricating oil to return to compressor 3 in a timely and efficient manner.

[0062] It is understood that the heat exchanger 5 mentioned above can be a shell-and-tube heat exchanger or a plate heat exchanger, etc., and this embodiment does not make specific limitations on it.

[0063] Optionally, the heat exchanger 5 includes a fifth end 51 and a sixth end 52 opposite to each other along the flow direction. A first inlet 511 is disposed at the fifth end 51 and is disposed near the top of the fifth end 51. A first outlet 521 is disposed at the sixth end 52 and is disposed near the bottom of the sixth end 52.

[0064] By positioning the first inlet 511 near the top of the fifth end 51 and the first outlet 521 near the bottom of the sixth end 52, this top-in, bottom-out configuration allows the lubricating oil to sink to the bottom by gravity, eliminating the need for an additional power unit and simplifying the structure of the entire refrigeration system 100. Furthermore, this configuration lengthens the flow path of the refrigerant and lubricating oil within the heat exchanger 5, ensuring sufficient contact with the heat exchange medium and thus improving heat exchange efficiency.

[0065] It is understandable that the heat exchange medium mentioned above can be additionally provided media such as water or heat transfer oil, or it can be high-temperature liquid refrigerant and lubricating oil discharged from the outlet of compressor 3.

[0066] In some embodiments, the refrigeration system 100 further includes a liquid storage tank 522a. The heat exchanger 5 includes a second inlet 522 and a second outlet 512 disposed opposite to each other. The second inlet 522 is located at the sixth end 52 and is spaced apart from the first outlet 521. The second outlet 512 is located at the fifth end 51 and is spaced apart from the first inlet 511. The second inlet 522 and the second outlet 512 are connected by a fifth pipe 512a. The liquid storage tank 522a is configured to store high-temperature liquid refrigerant and lubricating oil supplied by the compressor 3, and to supply the high-temperature liquid refrigerant and lubricating oil to the fifth pipe 512a for heat exchange.

[0067] By setting up a liquid receiver 522a to store the high-temperature liquid refrigerant and lubricating oil discharged from the compressor 3, and by also delivering the high-temperature liquid refrigerant and lubricating oil to the fifth pipeline 512a for heat exchange, the refrigerant and lubricating oil in the second pipeline 511a can be heated without additional energy consumption.

[0068] It is understood that the above-mentioned liquid storage tank 522a can be a vertical liquid storage tank or a horizontal liquid storage tank, and this embodiment does not make specific limitations on this.

[0069] Optionally, the second outlet 512 is connected to the pump body 2 via a pipeline so that the heat exchanger 5 can send the refrigerant and lubricating oil after heat exchange in the fifth pipeline 512a into the pump body 2.

[0070] By connecting the second outlet 512 of the heat exchanger 5 to the pump body 2, the refrigerant and lubricating oil that have undergone heat exchange in the heat exchanger 5 can directly enter the pump body 2 to continue participating in the refrigeration cycle. In this process, the heat exchanger 5 can make full use of the heat or cold energy of the refrigerant and lubricating oil, thereby reducing ineffective heat exchange of the refrigerant in the system and improving the heat exchange efficiency of the entire refrigeration system 100.

[0071] In addition, the connection between the heat exchanger 5 and the pump body 2 allows the lubricating oil after heat exchange to be pumped back into components such as the ejector 4 for separation and circulation, which helps to maintain the stable circulation of lubricating oil within the refrigeration system 100.

[0072] In some embodiments, the first outlet 521 of the heat exchanger 5 is connected to an oil storage pipe 6, which is connected to the inlet of the compressor 3. The oil storage pipe 6 is configured to store lubricating oil and to allow refrigerant to pass through to the compressor 3.

[0073] After the refrigerant vaporizes in heat exchanger 5, it may still carry a small amount of liquid lubricating oil or incompletely vaporized refrigerant. By connecting an oil receiver pipe 6 downstream of heat exchanger 5, the gas and liquid phases can be further separated. The gaseous refrigerant can directly enter compressor 3 through oil receiver pipe 6, while the liquid lubricating oil is deposited in oil receiver pipe 6 due to gravity, preventing liquid refrigerant from entering compressor 3 and potentially causing "liquid slugging" (compression of liquid substances leading to damage to compressor 3).

[0074] In addition, the separated lubricating oil can be temporarily stored through the oil storage pipe 6. When the detection module detects that the amount of lubricating oil in the compressor 3 is insufficient, the lubricating oil stored in the oil storage pipe 6 is sent back to the compressor 3. When the amount of oil in the compressor 3 is sufficient, the return of oil to the compressor 3 can be temporarily suspended. This allows for flexible control of the return of oil to the compressor 3, preventing situations where there is too much or too little lubricating oil in the compressor 3, which could affect the normal operation of the compressor 3.

[0075] Please see Figure 1 , Figure 3 and Figure 4 , Figure 4 This is a schematic diagram of the lubricating oil not covering the oil reservoir as disclosed in the embodiments of this application; Figure 5 This is a schematic diagram of lubricating oil covering the oil storage section as disclosed in the embodiments of this application. Optionally, the oil storage pipe 6 is a U-shaped pipe, including a third pipe 61, an oil storage section 62 and a fourth pipe 63 connected in sequence. The third pipe 61 is connected to the first outlet 521, the fourth pipe 63 is connected to the inlet of the compressor 3, and the oil storage section 62 is configured to store lubricating oil.

[0076] The oil receiver pipe 6 is a U-shaped pipe, and the oil storage section 62 utilizes gravity separation to allow liquid lubricating oil to deposit in the oil storage section 62, while gaseous refrigerant can pass through the entire oil receiver pipe 6 and return to the compressor 3. This prevents excessive lubricating oil in the refrigerant gas from being carried back into the compressor 3, thereby improving the compressor 3's compression efficiency. Furthermore, the U-shaped pipe is a purely mechanical structure, requiring no electric components or complex control logic, resulting in low manufacturing costs, durability, and easy maintenance.

[0077] It is understandable that the oil reservoir 62 has a certain pipe width, and when the lubricating oil is not completely blocked along the pipe width (such as...). Figure 4 As shown), gaseous refrigerant can pass directly through the oil reservoir 62, while when the lubricating oil is completely blocked along the width of the pipeline (as shown), Figure 5 As shown, since gaseous refrigerant will still enter the third pipeline 61, a pressure difference will be formed on both sides of the lubricating oil, which will push the lubricating oil stored in the oil reservoir 62 back into the compressor 3.

[0078] In some embodiments, the refrigeration system 100 further includes a low-pressure circulation tank 7, which is connected to the evaporator 1, the pump body 2, the second outlet 512, and the compressor 3 via pipelines. The inlet of the low-pressure circulation tank 7 is configured to receive the gas-liquid mixture of refrigerant and lubricating oil delivered by the evaporator 1 and the fifth pipeline 512a. The low-pressure circulation tank 7 is used for gas-liquid separation. The separated gaseous refrigerant is delivered to the compressor 3 via pipelines, and the separated liquid refrigerant and lubricating oil are delivered to the pump body 2 via pipelines. The outlet of the pump body 2 is connected to the inlet of the evaporator 1 via a pipeline so that the liquid refrigerant and lubricating oil are delivered to the evaporator 1 via pipelines.

[0079] By setting up a low-pressure circulation tank 7 to receive the gas-liquid mixture of refrigerant and lubricating oil from the evaporator 1 and the fifth pipeline 512a, and performing gas-liquid separation, the separated gaseous refrigerant can be transported separately to the compressor 3 through the pipeline, while the liquid refrigerant and lubricating oil are transported to the pump body 2. This separation method prevents the liquid refrigerant from directly entering the compressor 3 and causing liquid slugging, thereby protecting the compressor 3 from damage and ensuring the stable and reliable operation of the entire refrigeration system 100.

[0080] In addition, the outlet of pump body 2 is connected to the inlet of evaporator 1 via a pipe, which allows the pump body 2 to return liquid refrigerant and lubricating oil to evaporator 1. The presence of pump body 2 ensures that the refrigerant can continuously circulate between evaporator 1 and other components of refrigeration system 100, thereby maintaining a continuous and stable cooling effect.

[0081] It is understood that the aforementioned low-pressure circulation tank 7 can be a carbon steel tank or a stainless steel tank, etc., and this embodiment does not make specific limitations on it.

[0082] Optionally, a filter device 411b is also provided on the first pipeline 411. The filter device 411b is located near the pump body 2 relative to the solenoid valve 411a. The filter device 411b is configured to filter refrigerant and lubricating oil.

[0083] During the operation of the refrigeration system 100, if these debris enters the compressor 3, pump body 2, or ejector 4, it may scratch the surface of the components, causing the compressor 3 and other components to malfunction. By installing a filter device 411b on the first pipeline 411, solid impurities such as metal debris, welding slag, and oxide scale in the refrigerant and lubricating oil can be effectively intercepted, thereby reducing the probability of malfunction of the refrigeration system 100.

[0084] It is understood that the above-mentioned filter device 411b can be a magnetic filter or a centrifugal filter, etc., and this embodiment does not specifically limit it.

[0085] Optionally, the refrigeration system 100 also includes a condenser 8, which is connected to the outlet of the compressor 3 and the inlet of the liquid storage tank 522a via pipelines. The condenser 8 is used to condense the high-temperature and high-pressure gaseous refrigerant discharged from the outlet of the compressor 3 into a high-temperature and high-pressure liquid refrigerant and then send it into the liquid storage tank 522a.

[0086] It is understood that the condenser 8 mentioned above can be a finned tube condenser 8 or a shell-and-tube condenser 8, etc., and this embodiment does not make specific limitations on it.

[0087] The following table shows the temperature and pressure parameters of each node in the refrigeration system of this application, using R410A as the refrigerant and polyester synthetic oil (POE, Polyolester) as the lubricant:

[0088]

[0089] The flow process of refrigerant and lubricating oil in the refrigeration system 100 disclosed in this application will be briefly described below:

[0090] First, the low-pressure circulating tank 7 separates the gas-liquid mixture of refrigerant and lubricating oil. The separated gaseous refrigerant returns to the compressor 3, while the separated liquid refrigerant and liquid lubricating oil enter the pump body 2. The pump body 2 pumps the liquid refrigerant into the first pipeline 411. The high-pressure liquid refrigerant and lubricating oil discharged from the compressor 3 outlet is sprayed into the ejector 4 through the nozzle 41, creating a low-pressure zone 423 at the connection between the suction chamber 42 and the diffuser 43. This zone draws the liquid refrigerant and lubricating oil from the first pipeline 411 into the suction chamber 42. As the liquid refrigerant flows through the suction chamber 42, its pressure gradually decreases, and it vaporizes below the saturated vapor pressure. It then flows through the diffuser 43 to slow down. Part of the vaporized refrigerant and liquid lubricating oil discharged from the ejector 4 enters the second pipeline 511a of the heat exchanger 5 through the first inlet 511. Simultaneously, the high-temperature, high-pressure gaseous refrigerant and liquid lubricating oil discharged from the compressor 3 outlet pass through the condenser 8, becoming high-temperature, high-pressure liquid refrigerant and lubricating oil, which are stored in the liquid storage tank 522a. The liquid storage tank 522a transports the high-temperature, high-pressure liquid refrigerant and lubricating oil to the fifth pipe 512a in the heat exchanger 5, where it exchanges heat with the partially vaporized refrigerant and liquid lubricating oil in the second pipe 511a, ensuring complete vaporization of the refrigerant in the second pipe 511a. The first outlet 521 sends the separated gaseous refrigerant and liquid lubricating oil into the oil storage pipe 6. The gaseous refrigerant returns to the compressor 3 through the oil storage pipe 6, while the liquid lubricating oil is stored in the oil storage section 62. When the detection module detects that the lubricating oil level in the compressor 3 is insufficient, the lubricating oil stored in the oil storage section 62 is sent back to the compressor 3. The partially vaporized refrigerant and liquid oil discharged from the second outlet 512 of the heat exchanger 5 are discharged into the evaporator 1. The liquid refrigerant absorbs heat and evaporates, thus becoming a gas-liquid mixture of refrigerant and liquid lubricating oil, which is discharged into the low-pressure circulation tank 7 to continue gas-liquid separation, thereby realizing the circulation of refrigerant and lubricating oil in the entire refrigeration system 100.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A refrigeration system, characterized in that, The refrigeration system includes: Evaporator; A pump body, with piping connected to the evaporator, is configured to receive liquid refrigerant and lubricating oil from the evaporator and pump them out from the outlet of the pump body; A compressor configured to compress the refrigerant in a low-pressure gaseous state into the refrigerant in a high-pressure gaseous state, the compressor having a detection module for detecting the amount of lubricating oil in the compressor; Multiple ejectors are connected in parallel. The inlet of each ejector is connected to the outlet of the pump body via a first pipeline to deliver the liquid refrigerant and the lubricating oil to the ejector through the first pipeline. The ejector is configured to vaporize the refrigerant to separate the refrigerant and the lubricating oil. The outlet pipeline of the ejector is connected to the inlet of the compressor to return the separated lubricating oil and refrigerant to the compressor. A solenoid valve is provided on the first pipeline to control the opening and closing of the first pipeline and the inlet of the ejector. A control device is electrically connected to the detection module and the solenoid valve. The control device is used to control the number of solenoid valves to be activated based on the amount of lubricating oil in the compressor detected by the detection module.

2. The refrigeration system according to claim 1, characterized in that, The ejector includes a nozzle, a suction chamber, and a diffuser. The suction chamber includes a first end and a second end along the flow direction. The diffuser includes a third end and a fourth end along the flow direction. The second end and the third end are connected. The inlet of the nozzle is connected to the outlet of the compressor. The outlet of the nozzle is located at the connection between the second end and the third end, so that the nozzle is connected to both the suction chamber and the diffuser. The nozzle is configured to inject high-pressure liquid refrigerant and lubricating oil into the connection between the second end and the third end to create a low-pressure zone in the suction chamber, thereby drawing the liquid refrigerant and lubricating oil in the first pipeline into the low-pressure zone. The cross-sectional area of ​​the suction chamber, perpendicular to the flow direction, gradually decreases from the first end to the second end to vaporize the refrigerant. The cross-sectional area of ​​the diffuser, perpendicular to the flow direction, gradually increases from the third end to the fourth end to reduce the flow rate of the refrigerant and the lubricating oil.

3. The refrigeration system according to claim 1, characterized in that, The refrigeration system further includes a heat exchanger, which includes a first inlet and a first outlet disposed opposite to each other, the first inlet and the first outlet being connected by a second pipeline, the first inlet being configured to be connected to the outlet of the ejector, the first outlet being configured to be connected to the inlet of the compressor, the heat exchanger being configured to introduce a heat exchange medium to exchange heat with the refrigerant and the lubricating oil in the second pipeline to vaporize the refrigerant, and the heat exchanger being further configured to send the separated lubricating oil into the compressor.

4. The refrigeration system according to claim 3, characterized in that, The heat exchanger includes a fifth end and a sixth end opposite to each other along the flow direction. The first inlet is disposed at the fifth end and is located near the top of the fifth end. The first outlet is disposed at the sixth end and is located near the bottom of the sixth end.

5. The refrigeration system according to claim 3, characterized in that, The first outlet of the heat exchanger is connected to an oil storage pipe, which is connected to the inlet of the compressor. The oil storage pipe is configured to store the lubricating oil and allow the refrigerant to pass through to enter the compressor.

6. The refrigeration system according to claim 5, characterized in that, The oil storage pipe is a U-shaped pipe, including a third pipe, an oil storage section and a fourth pipe connected in sequence. The third pipe is connected to the first outlet, the fourth pipe is connected to the inlet of the compressor, and the oil storage section is configured to store the lubricating oil.

7. The refrigeration system according to claim 4, characterized in that, The refrigeration system further includes a liquid storage tank, and the heat exchanger further includes a second inlet and a second outlet disposed opposite to each other. The second inlet is disposed at the sixth end and is spaced apart from the first outlet. The second outlet is disposed at the fifth end and is spaced apart from the first inlet. The second inlet and the second outlet are connected through a fifth pipeline. The liquid storage tank is connected to both the outlet of the compressor and the second inlet. The liquid storage tank is configured to store the high-temperature liquid refrigerant and the lubricating oil delivered by the compressor, and to deliver the high-temperature liquid refrigerant and the lubricating oil to the fifth pipeline for heat exchange.

8. The refrigeration system according to claim 7, characterized in that, The second outlet is connected to the pump body via a pipeline, so that the heat exchanger can deliver the refrigerant and the lubricating oil after heat exchange in the fifth pipeline into the pump body.

9. The refrigeration system according to claim 8, characterized in that, The refrigeration system also includes a low-pressure circulation tank, which is connected to the evaporator, the pump body, the second outlet, and the compressor via pipelines. The low-pressure circulation tank is used to separate the gas-liquid mixture of refrigerant and lubricating oil transported by the fifth pipeline and the evaporator, so that the separated gaseous refrigerant is transported to the compressor through the pipeline, and the separated liquid refrigerant and lubricating oil are transported to the pump body through the pipeline. The outlet of the pump body is connected to the inlet of the evaporator via a pipeline, so that the liquid refrigerant and lubricating oil are transported to the evaporator through the pipeline.

10. The refrigeration system according to any one of claims 1-9, characterized in that, The first pipeline is also equipped with a filter device, which is located near the pump body relative to the solenoid valve. The filter device is configured to filter the refrigerant and the lubricating oil.

Images