Refrigerating system and sorting tester

Abstract

The utility model relates to a refrigeration system and a sorting tester. The refrigerating system comprises a first compressor, a first condenser, a first throttling device and a first evaporator which are sequentially communicated to form a first closed loop; the refrigerating system further comprises an oil separator, a first pump and an oil return control flow path, the oil separator is located in the first closed loop, connected between the first compressor and the first condenser and used for separating refrigerants from oil, and an oil return opening of the oil separator communicates with the first compressor. The first pump is used for providing power for promoting a refrigerant of the first closed loop to flow to the first evaporator; and the oil return control flow path can be communicated with or disconnected from the first evaporator and the oil separator. The refrigerating system has an oil return mode, and when the refrigerating system is in the oil return mode, the oil return control flow path is in a communicated state, and the first pump is started. In the application, the deposited oil in the first evaporator is fed into the oil separator through the first pump and the oil return control flow path, and the oil is supplemented to the first compressor through the oil separator, so that the risk of oil shortage loss can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of two-stage refrigeration, and in particular to a refrigeration system and a sorting and testing machine. Background Art

[0002] Most of the sorting test machines use refrigeration system to adjust their test temperature. In the refrigeration process of the refrigeration system, the oil in the compressor is easily discharged with the refrigerant, and is easily deposited in the evaporator during the flow process.

[0003] Under low temperature conditions, the refrigeration demand of the sorting test machine is large, and the oil accumulated in the evaporator is easily carried away by the flowing refrigerant and returned to the compressor. Under high temperature test conditions, the refrigeration demand of the sorting test machine is small, and the refrigerant flow rate inside the evaporator is low. The refrigerant cannot effectively carry away the deposited oil in the evaporator, resulting in oil shortage and damage to the compressor. Utility Model Content

[0004] Based on this, it is necessary to provide a refrigeration system and a sorting test machine to address the problem that oil is easily deposited in the evaporator, causing the compressor to be damaged due to lack of oil.

[0005] In a first aspect, the present application provides a refrigeration system, the refrigeration system comprising:

[0006] A first compressor, a first condenser, a first throttling device and a first evaporator are sequentially connected to form a first closed loop;

[0007] an oil separator, located in the first closed loop and connected between the first compressor and the first condenser, for separating the refrigerant from the oil, the oil return port of the oil separator being connected to the first compressor;

[0008] a first pump, used for providing power to cause the refrigerant in the first closed loop to flow to the first evaporator;

[0009] an oil return control flow path capable of connecting or disconnecting the first evaporator and the oil separator;

[0010] The refrigeration system has an oil return mode. In the oil return mode, the oil return control flow path is in a connected state, and the first pump is turned on.

[0011] In some embodiments, the refrigeration system also includes a second pump and a first oil return pipeline, the first oil return pipeline connects the oil return port of the oil separator and the first compressor, and the second pump is arranged on the first oil return pipeline to provide power to cause the oil to flow back from the oil separator to the first compressor.

[0012] In some embodiments, the second pump is not turned on simultaneously with the first pump.

[0013] In some embodiments, the refrigeration system includes a cooling module for cooling the refrigerant flowing to the first evaporator; and / or,

[0014] The refrigeration system comprises a heating device, and the heating device is used to heat the oil separator to gasify the refrigerant in the oil separator.

[0015] In some embodiments, the cooling module includes a second compressor, a second condenser, a second throttling device and an evaporative condenser which are connected in sequence to form a second closed loop; on the first closed loop, the evaporative condenser serves as the first condenser, and the first closed loop and the second closed loop exchange heat via the evaporative condenser.

[0016] In some embodiments, the first pump is disposed in a flow path connected between the first throttling device and the first evaporator.

[0017] In some embodiments, the refrigeration system includes a bypass flow path, the first closed-loop circuit includes a first flow path connected between the first throttling device and the first evaporator, the bypass flow path is connected in parallel with the first flow path, and the first pump is arranged in the bypass flow path.

[0018] In some embodiments, a first circulation stop valve and a second circulation stop valve are provided on the bypass flow path, and the first pump is located between the first circulation stop valve and the second circulation stop valve.

[0019] In some embodiments, the oil return control flow path includes a second oil return pipeline and a second oil return stop valve, the first closed loop includes a second flow path between the first evaporator and the first compressor, and a gas return stop valve is provided on the second flow path;

[0020] The second flow path and the second oil return pipeline are independently arranged, and the air return stop valve and the second oil return stop valve are not opened at the same time.

[0021] In a second aspect, the present application provides a sorting test machine, comprising a test body and a refrigeration system as described in the above embodiment, wherein the refrigeration system is used to adjust the test temperature of the test body.

[0022] The above-mentioned refrigeration system and sorting test machine, when the refrigeration system is in the oil return mode, under the action of the first pump and the oil return control flow path, the deposited oil accumulated in the first evaporator can follow the high-speed flowing refrigerant to flow back to the oil separator and be stored, and can subsequently flow back to the first compressor through the oil separator to replenish oil for the first compressor, thereby reducing the risk of oil loss due to lack of oil in the first compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0024] Figure 1 A system schematic diagram of a refrigeration system according to some embodiments.

[0025] Figure 2 Schematic diagrams of refrigeration systems of other embodiments.

[0026] The reference numerals in the specific implementation manner are as follows:

[0027] 100. Refrigeration system; 10. Low-temperature refrigeration module; S1. First closed-loop circuit; S11. First flow path; S12. Second flow path; 11. First compressor; 12. First condenser; 13. First throttling device; 14. First evaporator; 15. Oil separator; 16. Heating device; 17. First pump; 18. Second pump; L. Oil return control flow path; M. Bypass flow path; G1. First oil return pipeline; G2. Second oil return pipeline; F1. First oil return stop valve; F2. Second oil return stop valve; F3. Return air stop valve; F4. First circulation stop valve; F5. Second circulation stop valve; 20. Cooling module; S2. Second closed-loop circuit; 21. Second compressor; 22. Second condenser; 23. Second throttling device; 24. Evaporative condenser. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0029] In the description of the present application, it should be understood that terms such as “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships, if any, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0030] In addition, if present, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In this application, unless otherwise clearly specified and limited, if any, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] In the present application, if it appears, unless otherwise clearly specified and limited, a first feature “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature “above”, “above” and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature “below”, “below” and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0033] It should be noted that, if present, when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0034] The present application proposes a refrigeration system to solve the problem mentioned in the background technology that oil is easily deposited in the evaporator of the refrigeration system, resulting in damage to the compressor due to lack of oil.

[0035] Please refer to Figure 1 The refrigeration system 100 in the embodiment of the present application includes a first compressor 11, a first condenser 12, a first throttling device 13 and a first evaporator 14 which are sequentially connected to form a first closed loop S1.

[0036] When the refrigeration system 100 is cooling, the flow process of the refrigerant in the first closed loop S1 is roughly as follows: the first compressor 11 discharges high-temperature and high-pressure gaseous refrigerant, and when the high-temperature and high-pressure gaseous refrigerant passes through the first condenser 12, it is condensed into medium-temperature and high-pressure liquid refrigerant by the first condenser 12, and is expanded and reduced in pressure by the first throttling device 13 to become low-temperature and low-pressure liquid refrigerant, and when the low-temperature and low-pressure liquid refrigerant passes through the first evaporator 14, it absorbs external heat to adjust the load temperature, and finally flows back to the first compressor 11, and the cycle repeats.

[0037] In addition, the refrigeration system 100 further includes an oil separator 15 , a first pump 17 and an oil return control flow path L.

[0038] The oil separator 15 is located in the first closed loop S1 and connected between the first compressor 11 and the first condenser 12 for separating the refrigerant from the oil. The oil return port of the oil separator 15 is connected to the first compressor 11 .

[0039] It is easy to understand that when the high-temperature and high-pressure gaseous refrigerant is discharged from the first compressor 11, it is easy to carry the oil in the first compressor 11 into the first closed loop S1. Before the mixture of refrigerant and oil discharged from the first compressor 11 flows to the first condenser 12, it first passes through the oil separator 15 to separate the gaseous refrigerant from the oil. The separated gaseous refrigerant continues to flow to the first condenser 12, and the separated oil remains in the oil separator 15 and can flow back to the first compressor 11 through the oil return port of the oil separator 15 to replenish the oil to the first compressor 11.

[0040] The first pump 17 is used to provide power to force the refrigerant in the first closed loop S1 to flow toward the first evaporator 14 .

[0041] The first pump 17 can be set on the first closed loop S1 or on a bypass connected in parallel with the first closed loop S1. It provides power to cause the refrigerant in the first closed loop S1 to flow to the first evaporator 14, so as to increase the flow speed of the refrigerant in the first evaporator 14, and use the high-speed flowing refrigerant to flush away the deposited oil in the first evaporator 14, thereby reducing the amount of oil deposited in the first evaporator 14.

[0042] In the flow path of the refrigerant, the first pump 17 is usually located upstream of the first evaporator 14. Specifically, the first pump 17 can be arranged on the first closed loop S1 between the first condenser 12 and the first evaporator 14, or the first pump 17 is arranged on a bypass arranged in parallel with the first closed loop S1 between the first condenser 12 and the first evaporator 14.

[0043] The oil return control flow path L can connect or disconnect the first evaporator 14 and the oil separator 15 .

[0044] The oil return control flow path L is connected between the outlet of the first evaporator 14 and the inlet of the oil separator 15 , and can control itself to connect or disconnect the first evaporator 14 and the oil separator 15 .

[0045] The refrigeration system 100 has an oil return mode. In the oil return mode, the oil return control flow path L is in a connected state, and the first pump 17 is turned on.

[0046] When the refrigeration system 100 stops refrigeration and the first compressor 11 stops, the refrigeration system 100 enters the oil return mode. In the oil return mode, the oil return control flow path L is switched to a connection state connecting the first evaporator 14 and the oil separator 15, and the first pump 17 is turned on.

[0047] After the first pump 17 is turned on, the power it provides causes the refrigerant on the first closed loop S1 to flow at high speed to flush the deposited oil in the first evaporator 14. The refrigerant carries the deposited oil out of the first evaporator 14 and then is discharged to the oil separator 15 through the oil return control flow path L.

[0048] When the above-mentioned refrigeration system 100 is in the oil return mode, under the action of the first pump 17 and the oil return control flow path L, the deposited oil accumulated in the first evaporator 14 can first flow back to the oil separator 15 and be stored along with the high-speed flowing refrigerant, and then flow back to the first compressor 11 through the oil separator 15 to replenish oil for the first compressor 11, thereby reducing the risk of oil loss of the first compressor 11.

[0049] In some embodiments, reference Figure 1 The refrigeration system 100 also includes a second pump 18 and a first oil return pipeline G1. The first oil return pipeline G1 connects the oil return port of the oil separator 15 and the first compressor 11. The second pump 18 is arranged on the first oil return pipeline G1 to provide power to cause the oil to flow back from the oil separator 15 to the first compressor 11.

[0050] The first oil return pipeline G1 is used to return the oil in the oil separator 15 to the first compressor 11. A second pump 18 is arranged on the first oil return pipeline G1. When the second pump 18 is started, the oil in the oil separator 15 can be returned to the first compressor 11 faster.

[0051] In actual application, when the refrigeration system 100 enters the early stage of the refrigeration phase, before starting the first compressor 11 for refrigeration, the second pump 18 can be controlled to start, so that the oil remaining in the oil separator 15 can quickly flow back to the first compressor 11, and the first compressor 11 can be replenished with oil. Of course, after the refrigeration system 100 stops refrigeration and the first compressor 11 stops, the second pump 18 can be controlled to start, so that the oil remaining in the oil separator 15 can quickly flow back to the first compressor 11, so as to facilitate the rapid entry of the next round of refrigeration.

[0052] At this time, a second pump 18 is provided on the first oil return pipeline G1 to accelerate the oil retained in the oil separator 15 to quickly return to the first compressor 11, replenish oil for the first compressor 11, and help accelerate the refrigeration system 100 to enter refrigeration operation.

[0053] In some embodiments, the second pump 18 is not turned on simultaneously with the first pump 17 .

[0054] When the second pump 18 is turned on, the oil separator 15 returns oil to the first compressor 11. When the first pump 17 is turned on, the first evaporator 14 returns oil to the oil separator 15. In actual application, in the oil return mode, the first compressor 11 is stopped, the first pump 17 is turned on, and the second pump 18 is not started. The oil returned from the first evaporator 14 to the oil separator 15 is first stored in the oil separator 15. After the subsequent oil return mode ends, the oil in the oil separator 15 is returned to the first compressor 11 by starting the second pump 18.

[0055] At this time, the two stages of oil return from the first evaporator 14 to the oil separator 15 and oil return from the oil separator 15 to the first compressor 11 are carried out separately, which can avoid that when the first evaporator 14 returns oil to the oil separator 15, the liquid refrigerant that has not had time to vaporize follows the oil and is pumped by the second pump 18 to flow to the first compressor 11, and liquid hits the first compressor 11.

[0056] In some embodiments, reference Figure 2 The refrigeration system 100 includes a cooling module 20 for cooling the refrigerant flowing to the first evaporator 14 .

[0057] Optionally, the cooling module 20 cools the first closed loop S1 between the first throttling device 13 and the first evaporator 14, or cools the first closed loop S1 between the first throttling device 13 and the first condenser 12, or directly cools the first condenser 12 (in this case, the cooling module 20 can be a cooling device carried by the first condenser 12 itself, such as a water cooling device, etc.).

[0058] When cooling the first closed loop S1, the cooling module 20 can liquefy the refrigerant in the first closed loop S1, so that a large amount of liquid refrigerant enters the first evaporator 14. The high-speed flowing liquid refrigerant has a better flushing effect on the oil deposited in the first evaporator 14, thereby increasing the oil return amount of the first evaporator 14.

[0059] Of course, in other embodiments, the refrigeration system 100 may not independently set up the cooling module 20. In the oil return mode when the refrigeration system 100 stops refrigeration, the high-speed gaseous refrigerant in the first closed loop S1 is used to flush the deposited oil in the first evaporator 14.

[0060] In some embodiments, reference Figure 1 and Figure 2 The refrigeration system 100 includes a heating device 16 , which is used to heat the oil separator 15 to gasify the refrigerant in the oil separator 15 .

[0061] The heating device 16 is usually arranged outside the oil separator 15, which is simple and convenient. Of course, the heating device 16 can also be arranged inside the oil separator 15. The heating device 16 can be a resistive heating device 16, an infrared heating device 16, a heating barrel, etc.

[0062] Understandably, when there is liquid refrigerant in the first closed loop S1, part of the refrigerant discharged from the first evaporator 14 is liquid, and after the liquid refrigerant enters the oil separator 15, it is easy to mix with the oil and remain in the oil separator 15, so that the amount of refrigerant participating in the circulation on the first closed loop S1 is reduced. At this time, a heating device 16 is provided at the oil separator 15, and the heating device 16 can gasify the liquid refrigerant in the oil separator, and the gaseous refrigerant flows out of the oil separator 15 and continues to circulate in the first closed loop S1.

[0063] In this way, in the oil return mode, under the impetus of the first pump 17, a certain flow rate of high-speed flowing refrigerant can continue to exist to participate in multiple flushing of the deposited oil in the first evaporator 14, thereby improving the flushing effect of the deposited oil in the first evaporator 14, which is beneficial to increasing the return oil volume of the first evaporator 14.

[0064] Moreover, when the refrigeration system 100 is provided with a cooling module 20, in the oil return mode, the cooling module 20 and the heating device 16 are both turned on. Under the action of the refrigerant module 20, the refrigerant flowing from the first evaporator 14 to the oil separator 15 is mainly liquid refrigerant, and the setting effect of the heating device 16 is more obvious. A large amount of liquid refrigerant can be fully gasified by the heating device 16 in the oil separator 15, and then can enter the first closed loop S1 for circulation, ensuring the circulating refrigerant content in the first closed loop S1 and increasing the oil return amount of the first evaporator 14.

[0065] It can be seen that in the oil return mode, the cooling module 20 and the heating device 16 are both turned on.

[0066] It is worth adding that the heating device 16 can be turned on not only in the oil return mode, but also when the second pump 18 is turned on, so that when the oil separator 15 returns oil to the first compressor 11, the liquid refrigerant will not be sent to the first compressor 11 through the first oil return pipeline.

[0067] It should be noted that the cooling module 20 may be a water cooling device for circulating cooling water, and may also be, but is not limited to, adopting the solutions in the following embodiments.

[0068] In some embodiments, reference Figure 2The cooling module 20 includes a second compressor 21, a second condenser 22, a second throttling device 23 and an evaporative condenser 24 which are connected in sequence to form a second closed loop S2; on the first closed loop S1, the evaporative condenser 24 serves as the first condenser 12, and the first closed loop S1 and the second closed loop S2 exchange heat via the evaporative condenser 24.

[0069] The first compressor 11, the first condenser 12, the first throttling device 13 and the first evaporator 14 are connected in sequence to form a first closed loop S1, and serve as a low-temperature refrigeration module 10. The second compressor 21, the second condenser 22, the second throttling device 23 and the evaporative condenser 24 are connected in sequence to form a second closed loop S2, and serve as a high-temperature refrigeration module (i.e., cooling module 20).

[0070] The second closed loop S2 of the high temperature refrigeration module and the first closed loop S1 of the low temperature refrigeration module 10 exchange heat through the evaporative condenser 24. The evaporative condenser 24 is used as the first evaporator of the high temperature refrigeration module and also as the first condenser 12 of the low temperature refrigeration module 10.

[0071] The high-temperature refrigeration module formed by the cooling module 20 exchanges heat with the low-temperature refrigeration module 10 where the first evaporator 14 is located through the evaporative condenser 24, so that the refrigeration system 100 becomes a cascade refrigeration system.

[0072] When the refrigeration system 100 is in the oil return mode, the cooling module 20 is turned on (i.e., the second compressor 21 is started), and the first compressor 11 is stopped. The low-temperature refrigerant generated by the high-temperature refrigeration module exchanges heat with the gaseous refrigerant flowing through the evaporative condenser 24 in the first closed loop S1, so that the refrigerant flowing out of the evaporative condenser 24 on the first closed loop S1 has a high degree of liquefaction, which increases the content of the liquid refrigerant flowing into the first evaporator 14, so that the flushing effect of the deposited oil in the first evaporator 14 is better, and the first evaporator 14 can return more oil to the oil separator 16.

[0073] Of course, by using a high-temperature refrigeration module as the cooling module 20, in addition to increasing the content of liquid refrigerant flowing to the first evaporator 14 on the first closed-loop circuit S1 in the oil return mode of the refrigeration system 100, it is also possible to reduce the refrigerant temperature on the first closed-loop circuit S1 when the refrigeration system 100 is in the refrigeration stage, thereby improving the refrigeration effect of the refrigeration system 100, thereby achieving multiple technical effects at one stroke.

[0074] In some embodiments, reference Figure 1, the first pump 17 is arranged on the flow path connected between the first throttling device 13 and the first evaporator 14. At this time, on the flow path of the refrigerant in the first closed loop S1, the first pump 17 is located upstream of the first evaporator 14, and the first pump 17 is arranged close to the first evaporator 14. The liquid refrigerant sent by the first pump 17 only needs to flow a short distance to enter the first evaporator 14, and the kinetic energy loss of the liquid refrigerant is less, and the flushing effect of the deposited oil in the first evaporator 14 is better.

[0075] In some embodiments, reference Figure 1 The refrigeration system 100 includes a bypass flow path M, the first closed loop S1 includes a first flow path S11 connected between the first throttling device 13 and the first evaporator 14, the bypass flow path M is connected in parallel with the first flow path S11, and the first pump 17 is arranged on the bypass flow path M.

[0076] When the refrigeration system 100 is refrigerating normally, the first pump 17 is not started. The refrigerant can flow to the first evaporator 14 through the first flow path S11. When the refrigeration system 100 is in the oil return mode, the first pump 17 is started, and the refrigerant can enter the first pump 17 through the bypass flow path M, and under the push of the first pump 17, quickly enter the first evaporator 14 to flush the deposited oil in the first evaporator 14.

[0077] At this time, the first pump 17 is set on the bypass flow path M. When the refrigeration system 100 is refrigerating normally, the failure of the first pump 17 to start will not affect the normal flow of the refrigerant to the first evaporator 14, and will not affect the normal operation of the refrigeration system 100.

[0078] Specifically in the embodiment, refer to Figure 1 A first circulation shutoff valve F4 and a second circulation shutoff valve F5 are provided on the bypass flow path M, and the first pump 17 is located between the first circulation shutoff valve F4 and the second circulation shutoff valve F5.

[0079] When the refrigeration system 100 is in the oil return mode, the first circulation stop valve F4 and the second circulation stop valve F5 are opened to allow the refrigerant to smoothly enter the bypass flow path M under the pumping of the first pump 17, and can smoothly flow to the first evaporator 14 through the bypass flow path M. When the refrigeration system 100 is refrigerating normally, the first circulation stop valve F4 and the second circulation stop valve F5 are both closed, so that the refrigerant can be prevented from flowing to the first pump 17 and affecting the total amount of refrigerant circulation on the first closed loop S1.

[0080] In some embodiments, reference Figure 1The oil return control flow path L includes a second oil return pipeline G2 and a second oil return stop valve F2, the first closed loop S1 includes a second flow path S12 located between the first evaporator 14 and the first compressor 11, and a gas return stop valve F3 is provided on the second flow path S12. The second flow path S12 is independently provided with the second oil return pipeline G2, and the gas return stop valve F3 and the second oil return stop valve F2 are not opened at the same time.

[0081] When the second oil return stop valve F2 is closed, the oil return control flow path L is disconnected from the first evaporator 14 and the oil separator 15. When the second oil return stop valve F2 is opened, the oil return control flow path L is connected to the first evaporator 14 and the oil separator 15.

[0082] When the refrigeration system 100 is refrigerating normally, the return air stop valve F3 is opened, the second return oil stop valve F2 is closed, and the refrigerant flowing out of the first evaporator 14 flows back to the first compressor 11 through the second flow path S12, so as to circulate in the first closed loop S1 under the action of the first compressor 11, and then continue to refrigerate. When the refrigeration system 100 is in the oil return mode, the first compressor 11 is turned off, the return air stop valve F3 is closed, and the second return oil stop valve F2 is opened. The mixture of refrigerant and oil flowing out of the first evaporator 14 cannot flow back to the first compressor 11 directly, but flows back to the oil separator 15 through the second return oil pipeline G2.

[0083] In this way, the second oil return pipeline G2 independently set from the second flow path S12 realizes the connection between the first evaporator 14 and the oil separator 15. The setting of the return air stop valve F3 and the second oil return stop valve F2 can prevent the first evaporator 14 from returning oil to the first compressor 11 in the oil return mode, thereby preventing liquid hammer.

[0084] Specifically in one embodiment, Figure 1 As shown, the first oil return pipeline G1 is connected to the second flow path S12, and is connected to the first compressor 11 through the second flow path S12. A first oil return stop valve F1 is provided on the first oil return pipeline G1, and the first oil return stop valve F1 is located between the second pump 18 and the second flow path S12. The first oil return stop valve F1 is started synchronously with the second pump 18. During normal refrigeration, the first oil return stop valve F1 can prevent the refrigerant on the second flow path S12 from flowing to the first oil return pipeline G1. Of course, in other embodiments, the first oil return pipeline G1 and the second flow path S12 can also be provided independently.

[0085] It can be understood that the refrigeration system 100 also includes a control system, which is connected to the first pump 17, the second pump 18, the first oil return stop valve F1, the second oil return stop valve F2, the first circulation stop valve F4, the second circulation stop valve F5, the return air stop valve F3 and other control devices mentioned above to control the operation of each component.

[0086] In addition, an embodiment of the present application further provides a sorting test machine, including a test body and the refrigeration system 100 described in the above embodiment, and the refrigeration system 100 is used to adjust the test temperature of the test body.

[0087] The sorting test machine is used to perform sorting tests on semiconductor devices such as chips. The test subject can be a test cavity, a test pressure head, etc. The test cavity is a cavity structure used to provide a test space, and a plurality of chips and test components can be stored in the test space. The first evaporator 14 of the refrigeration system 100 can be arranged in the test space to adjust the test temperature of the test space. The test pressure head refers to a pressure head structure that can be pressed down and abutted on the chip, which is in direct contact with the chip to regulate the temperature of the chip. The first evaporator 14 of the refrigeration system 100 can be directly set on the test pressure head, for example, a channel structure serving as the internal flow channel of the first evaporator 14 is formed on the test pressure head. In the embodiment of the present application, there is no limitation on the specific type of the test subject.

[0088] In one embodiment, referring to Figure 2 The refrigeration system 100 includes a low-temperature refrigeration module 10 and a high-temperature refrigeration module as a cooling module 20. The low-temperature refrigeration module includes a first compressor 11, a first condenser 12, a first throttling device 13, and a first evaporator 14 located in a first closed loop S1. The high-temperature refrigeration module includes a second compressor 21, a second condenser 22, a second throttling device 23, and an evaporative condenser 24 located in a second closed loop S2. The evaporative condenser 24 integrates the function of the first condenser 12 into one, and the first closed loop S1 and the second closed loop S2 exchange heat through the evaporative condenser 24.

[0089] The low temperature refrigeration module 10 further includes an oil separator 15, a heating device 16, a first pump 17, and a second pump 18. The oil separator 15 is arranged in the first closed loop S1 and connected between the first compressor 11 and the first condenser 12. The oil return port of the oil separator 15 is connected to the first compressor 11 through the first oil return pipeline G1. The second pump 18 and the first oil return stop valve F1 are arranged on the first oil return pipeline G1. The heating device 16 is used to heat the oil separator 15. The first pump 17 is arranged on the bypass flow path M arranged in parallel with the first flow path S11. The first circulation stop valve F4 and the second circulation stop valve F5 are also arranged on the bypass flow path M. The outlet of the first evaporator 14 is connected to the inlet of the oil separator 15 through the oil return control flow path L, and the oil return control flow path L includes a second oil return control valve.

[0090] In some application scenarios, the test sorting machine has a test condition and a non-test condition. Under the test condition, the refrigeration system 100 can also have a normal refrigeration mode and a temperature control cycle mode. In the normal refrigeration mode, the refrigeration system 100 can control the test subject to maintain the target test temperature for a long time. In the temperature control cycle mode, the refrigeration system 100 will frequently start and stop the first compressor and the second compressor to control the test subject to cycle between different test temperatures.

[0091] In one embodiment, the control process of the sorting test machine of the above embodiment is roughly as follows: under the test condition, the first circulation stop valve F4, the second circulation stop valve F5, and the second return oil stop valve F2 are controlled to be closed, and the first return oil stop valve F1 and the return air stop valve F3 are controlled to be opened.

[0092] When the refrigeration system 100 enters the initial stage of the normal refrigeration mode, the second pump 18 is first turned on to allow the oil in the oil separator 15 to flow back to the first compressor 11. After a preset time, the second pump 18 is turned off, and then the first compressor 11 and the second compressor 21 are started to enter the normal refrigeration stage. When the normal refrigeration mode ends, after the first compressor 11 and the second compressor 21 are stopped, the heating device 16 is started to liquefy the liquid refrigerant in the oil separator 15 to reduce the accumulation of the liquid refrigerant in the oil separator 15.

[0093] Under the test condition, when the refrigeration system 100 is in the temperature control circulation mode, after the first compressor 11 and the second compressor 21 are controlled to stop, the heating device 16 and the second pump 18 are turned on to pump the oil in the oil separator 15 into the first compressor 11. After maintaining the preset time, the heating device 16 and the second pump 18 are turned off.

[0094] Under non-test conditions, the first circulation stop valve F4, the second circulation stop valve F5, and the second oil return stop valve F2 are controlled to be opened, and the first oil return stop valve F1 and the gas return stop valve F3 are controlled to be closed. When entering the oil return mode, after the second compressor 21 is turned on for a preset time (so that a large amount of liquid refrigerant exists in the first closed loop S1), the first pump 17 and the heating device 16 are turned on (so that a large amount of high-speed liquid refrigerant flushes the first evaporator 14), and after maintaining the preset time, the first pump 17 and the heating device 16 are turned off.

[0095] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A refrigeration system, characterized in that: The refrigeration system comprises: A first compressor (11), a first condenser (12), a first throttling device (13) and a first evaporator (14) are sequentially connected to form a first closed loop (S1); an oil separator (15), located in the first closed loop (S1) and connected between the first compressor (11) and the first condenser (12), for separating the refrigerant from the oil, wherein the oil return port of the oil separator (15) is connected to the first compressor (11); a first pump (17) for providing power to cause the refrigerant in the first closed loop (S1) to flow toward the first evaporator (14); An oil return control flow path (L) capable of connecting or disconnecting the first evaporator (14) and the oil separator (15); The refrigeration system has an oil return mode. When in the oil return mode, the oil return control flow path (L) is in a connected state and the first pump (17) is turned on.

2. The refrigeration system according to claim 1, characterized in that: The refrigeration system further comprises a second pump (18) and a first oil return pipeline (G1); the first oil return pipeline (G1) is connected to the oil return port of the oil separator (15) and the first compressor (11); the second pump (18) is arranged on the first oil return pipeline (G1) to provide power to cause the oil to flow back from the oil separator (15) to the first compressor (11).

3. The refrigeration system according to claim 2, characterized in that: The second pump (18) and the first pump (17) are not started at the same time.

4. The refrigeration system according to claim 1, characterized in that: The refrigeration system comprises a cooling module (20) for cooling the refrigerant flowing to the first evaporator (14); and / or; The refrigeration system comprises a heating device (16), and the heating device (16) is used to heat the oil separator (15) to gasify the refrigerant in the oil separator (15).

5. The refrigeration system according to claim 4, characterized in that: The cooling module (20) comprises a second compressor (21), a second condenser (22), a second throttling device (23) and an evaporative condenser (24) which are sequentially connected to form a second closed loop (S2); on the first closed loop (S1), the evaporative condenser (24) serves as the first condenser (12), and the first closed loop (S1) and the second closed loop (S2) exchange heat via the evaporative condenser (24).

6. The refrigeration system according to any one of claims 1 to 4, characterized in that: The first pump (17) is arranged on a flow path connected between the first throttling device (13) and the first evaporator (14).

7. The refrigeration system according to claim 6, characterized in that: The refrigeration system comprises a bypass flow path (M), the first closed loop (S1) comprises a first flow path (S11) connected between the first throttling device (13) and the first evaporator (14); The bypass flow path (M) is connected in parallel with the first flow path (S11), and the first pump (17) is provided in the bypass flow path (M).

8. The refrigeration system according to claim 7, characterized in that: A first circulation stop valve (F4) and a second circulation stop valve (F5) are provided on the bypass flow path (M), and the first pump (17) is located between the first circulation stop valve (F4) and the second circulation stop valve (F5).

9. The refrigeration system according to any one of claims 1 to 4, characterized in that: The oil return control flow path (L) comprises a second oil return pipeline (G2) and a second oil return stop valve (F2); the first closed loop (S1) comprises a second flow path (S12) located between the first evaporator (14) and the first compressor (11); and a gas return stop valve (F3) is arranged on the second flow path (S12); The second flow path (S12) and the second oil return pipeline (G2) are independently arranged, and the air return stop valve (F3) and the second oil return stop valve (F2) are not opened at the same time.

10. A sorting and testing machine, characterized in that: It comprises a test body and a refrigeration system as claimed in any one of claims 1 to 9, wherein the refrigeration system is used to adjust the test temperature of the test body.

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