A method and structure for identifying and judging the oil injection amount of a compressor

Abstract

The present invention discloses a method and a recognition structure for identifying and judging the oil injection amount of a compressor. The method includes obtaining the oil storage amount at the bottom of the lower housing of the compressor, denoted as V1; obtaining the oil amounts contained in each moving pair of the pump body and the motor stator winding in the compressor, denoted as V2; obtaining the oil amount discharged from the compressor into the refrigeration cycle system, denoted as V3; and the total oil injection amount of the compressor is V, then V = V1 + V2 + V3. The method for identifying and judging the oil injection amount of this compressor can accurately judge the oil injection amount, fully consider the oil consumption problems of each part and each link during the operation of the compressor, enable the oil amount of each part to be precisely controllable, not only meet the full lubrication requirements of the compressor, but also establish the optimal filling amount of the compressor's refrigerant oil through this method, greatly improving the operation reliability of the compressor and the economy of oil filling.

Description

Technical Field

[0001] The invention relates to the technical field of compressor production, and in particular to a method and structure for identifying and judging the oil injection amount of a compressor. Background Art

[0002] At present, during the production process of reciprocating piston compressors, there are often abnormalities such as difficulty in starting the compressor or excessive shell temperature or even machine tripping. In addition, during the operation of the compressor, customers sometimes report abnormal mechanical sounds and the compressor's low-temperature time becomes significantly longer. After checking the compressor and checking the parts accuracy, assembly clearance and motor overload capacity, no faults such as parts accuracy, assembly clearance and motor were found. Finally, after analysis, it was found that the compressor refrigeration oil was insufficient. The compressor refrigeration oil plays a role in cooling and lubrication during the operation of the machine. As a result, the compressor refrigeration oil is insufficient, resulting in poor cooling and lubrication. The compressor has problems such as difficulty in starting, high shell temperature, and even tripping; and sometimes customers report abnormal mechanical sounds, and the compressor has significantly longer low-temperature time. There is no problem with the precision assembly clearance of parts. Finally, it is found that the compressor has too much refrigeration oil, which causes the motor rotor to contact the oil and mechanical oil stirring sound. At the same time, due to the large amount of oil filling, part of the oil is discharged to the customer's refrigeration system through the exhaust pipe, which not only occupies the heat exchange area, but also because the refrigerant dissolved in the oil increases, the mass flow of the refrigerant participating in the evaporation process decreases, affecting the heat exchange and cooling capacity, causing the customer's low-temperature time to be significantly longer. Sometimes, due to the failure of the oil filling equipment at the production site, the amount of refrigeration oil filling is too little or too much, resulting in similar problems with customers.

[0003] In addition, there is a situation where the compressor has been filled with the correct amount of oil. However, shortly after the compressor is put on the market, customers have successively reported difficulties in starting the compressor. There are even abnormal situations such as low refrigerating capacity and significantly increased power consumption. After dissecting the compressor shell for analysis, scratches or scoring are found on each moving pair of the compressor, and even abnormal situations such as high-temperature carbon deposition appear in the valve group part. By strengthening the control of part precision and assembly process requirements, customers still report abnormal situations such as difficult starting and low refrigerating capacity after using it for a period of time. After further investigation, it is found that the compressor has poor lubrication and leakage risks due to high temperature. The reason for the high temperature is that the refrigeration oil foams when the compressor is working. The generated bubbles of a certain volume will cause the refrigeration oil not to be evenly distributed on the surface of the moving friction pairs of the compressor. Some friction pair surfaces will have no refrigeration oil, resulting in insufficient lubrication of some areas of the friction pair surface, thereby increasing the wear and jamming risks between moving parts. When key components such as the crankshaft, piston, and connecting rod do not receive good lubrication when the refrigeration oil foams, excessive wear will occur, shortening the service life of the compressor. At the same time, due to the intensification of frictional heat, resulting in insufficient lubrication, the heat generated by friction cannot be carried away by the refrigeration oil, leading to a local temperature rise. Further reducing the performance of the refrigeration oil will also cause serious failures such as compressor jamming. Refrigeration oil bubbles may generate air gaps at sealing parts such as mating gaps, reducing the sealing effect. Poor oil seal will cause refrigerant leakage and reduce the efficiency of the refrigeration system. Summary of the Invention

[0004] The object of the present invention is to provide a method and structure for identifying and judging the oil injection amount of a compressor in view of the problems existing in the prior art.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for identifying and judging the oil injection amount of a compressor, the identification and judgment method comprising the following steps:

[0007] Obtain the oil storage amount at the bottom of the lower housing of the compressor, denoted as V1;

[0008] Obtain the oil amount contained in each moving pair of the inner pump body of the compressor and the motor stator winding, etc., denoted as V2;

[0009] Obtain the oil amount discharged from the compressor into the refrigeration cycle system, denoted as V3;

[0010] The total oil injection amount of the compressor is V, then V = V1 + V2 + V3.

[0011] Since the refrigerant is completely miscible with the refrigeration oil, when the compressor operates, a part of the refrigerant will be carried into the system, and at the same time, a part of the oil will infiltrate into the compressor moving pairs including the motor. Through experiments, the working oil amounts in three parts of the refrigeration cycle system during the operation of the compressor are determined. After the compressor operates in the refrigeration cycle system for a period of time, the refrigeration oil will adsorb on the surfaces of various moving pairs of the pump body, inside the motor stator winding, etc., and in the two heat exchangers of the refrigeration system. A part of the oil cannot return to the compressor. After the compressor stops, this method can identify the oil inlet depth of the oil suction pipe, and through the relationship between the filling amount and the oil inlet depth of the oil suction pipe, determine the optimal filling amount and the position of the optimal filling amount scale line. If too much refrigeration oil is filled, the refrigeration oil will enter the evaporator and condenser, occupying the heat exchange channels, reducing the thermal efficiency. At the same time, more refrigeration oil will dissolve more refrigerant, further reducing the amount of refrigerant participating in the refrigeration cycle, and also eliminating the influence of unnecessary overfilling of refrigeration oil on the refrigeration capacity.

[0012] Further, the method for obtaining the oil storage amount V1 is as follows: fabricate a visual lower housing assembly, install the pump body and the motor in the lower housing assembly, and keep the pump body horizontal;

[0013] Pour the refrigeration oil into the lower housing assembly, observe the oil level height and the gradually increasing oil inlet depth of the oil suction pipe of the crankshaft in the pump body until the oil level has immersed 1 / 2 - 2 / 3 of the lower winding of the motor stator;

[0014] Pick up the pump body and observe whether the lower end ring of the rotor on the pump body is oil-stained, and ensure that there is no oil stain on the lower end ring of the rotor. Record the poured oil amount, and this oil amount is the oil storage amount V1 at the bottom of the lower housing.

[0015] Further, the lower housing assembly is made of transparent tempered glass, or the lower housing assembly is fabricated according to the following method:

[0016] Select a compressor lower housing, cut it downward from the mating surface of the lower housing, cut off 2 / 3 - 3 / 4 to form a lower housing cutting assembly with a height of 1 / 4 - 1 / 3 of the original lower housing height.

[0017] Further, the method for obtaining the oil amount V2 is as follows: fabricate a visual upper housing assembly and a lower housing assembly, install the pump body and the motor in the upper housing assembly and the lower housing assembly according to the assembly requirements to obtain an assembled compressor;

[0018] Inject oil into the compressor through the process pipe on the lower housing assembly, and observe the oil level height in real time until the oil level has immersed 2 / 3 - 3 / 4 of the height of the lower winding of the motor stator. Pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, and ensure that the lower end ring of the rotor does not contact the oil surface. Record the oil amount V A ;

[0019] Seal the process pipe. Connect the air intake pipe on the lower housing assembly to the air hose, and connect the exhaust pipe to the oil guiding pipe. The oil guiding pipe is connected to the graduated cylinder.

[0020] Power on the compressor, introduce dry air or nitrogen through the air intake pipe, and record the volume V of the oil in the graduated cylinder after a period of testing. b ; At the same time, let the compressor stand still for 6 - 10 minutes after being powered on and running, and pour out the remaining oil volume V in the compressor. c Then the oil volume V2 = V A - V b - V c .

[0021] Furthermore, the method for obtaining the oil volume V3 is as follows: Manufacture a visual upper housing assembly and lower housing assembly, install the pump body and the motor in the upper housing assembly and the lower housing assembly according to the assembly requirements to obtain an assembled compressor.

[0022] Inject oil into the compressor through the process pipe on the lower housing assembly, observe the oil level height in real time until the oil level submerges 2 / 3 - 3 / 4 of the height of the lower wire package of the motor stator. Pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, ensure that the lower end ring of the rotor does not contact the oil surface, and record the oil volume V added to the compressor. A ;

[0023] Connect the compressor to the refrigeration cycle system, and an oil separator and an oil storage tank are provided in the refrigeration cycle system.

[0024] Vacuum the compressor and charge an appropriate amount of refrigerant. Power on the compressor and let the refrigeration system run stably for several hours. After the operation is completed, pour the oil in the oil separator into the graduated cylinder and record the oil volume V of the oil separator. d ;

[0025] Obtain the oil volume V e in the oil storage tank, then the oil volume V3 = V d +V e .

[0026] Furthermore, the method for obtaining the oil volume V e in the oil storage tank is as follows: Open the stop valve on the oil storage tank, and use nitrogen to blow the remaining oil in the high - pressure end of the refrigeration cycle system into the oil storage tank; Heat it at a temperature of 40 - 50 °C for several minutes, and record the oil volume V e in the oil storage tank after heating.

[0027] Further, the refrigeration cycle system includes a compressor, a first oil separator, a condenser, a filter, a throttling device, an evaporator and a second oil separator connected in sequence; a first oil storage tank with a stop valve is provided between the first oil separator and the condenser, and a second oil storage tank with a stop valve is provided between the second oil separator and the evaporator; a first gas charging valve is provided between the filter and the condenser, and a second gas charging valve is provided between the throttling device and the evaporator.

[0028] Further, after connecting the compressor to the refrigeration cycle system and placing the refrigeration cycle system in a constant temperature environment, evacuate the compressor. After the evacuation of the compressor is completed, charge an appropriate amount of refrigerant, and then power on the compressor to observe the oil stirring situation of the crankshaft in the pump body; if bubbles continuously emerge from the oil surface and do not disappear or even the volume of the bubbles becomes larger, it indicates that the anti-foaming performance of the compressor oil is unqualified, and there is a risk of difficult lubrication and poor sealing in the compressor; if no bubbles appear or the volume of the bubbles is small and the bubbles burst after foaming, it indicates that the anti-foaming performance of the compressor is qualified, and the oil injection volume of the compressor is also qualified, meeting the lubrication and sealing requirements of the compressor.

[0029] When the compressor is working, if the anti-foaming performance of the oil is poor after being stirred by the crankshaft, a certain volume of bubbles will cause the refrigeration oil not to be evenly distributed on the surface of the moving friction pairs of the compressor. There will be no refrigeration oil on the surface of some friction pairs, resulting in insufficient lubrication of some areas on the surface of the friction pairs, thereby increasing the risk of wear and jamming between the moving parts; when the key components such as the crankshaft, piston, and connecting rod are not well lubricated when the refrigeration oil foams, excessive wear will occur, shortening the service life of the compressor; at the same time, due to the intensification of frictional heat, resulting in insufficient lubrication, the heat generated by friction cannot be carried away by the refrigeration oil, leading to a local temperature rise, further reducing the performance of the refrigeration oil, and also causing serious failures such as compressor jamming; the bubbles in the refrigeration oil may also generate air gaps at the sealing parts such as the mating gaps, reducing the sealing effect. Poor oil seal will cause refrigerant leakage and reduce the efficiency of the refrigeration system. And through the above method, the working state of the oil during the operation of the compressor can be clearly seen. Once foaming occurs, the volume of the foam can be accurately identified through the scale line, and it can be determined whether the foaming performance is qualified. If the volume of the foam becomes larger and does not break, it indicates that the anti-foaming property of the refrigeration oil is unqualified, and an anti-foaming agent needs to be added. The added anti-foaming agent for the refrigeration oil can be verified for feasibility again through this device and method, greatly improving the reliability of the compressor.

[0030] An identification structure for the oil injection volume of a compressor is provided with a visual part on the compressor housing. There is a pump body and a motor inside the compressor housing. The lower end of the crankshaft in the pump body is provided with an oil suction pipe, and the oil suction pipe is connected to the refrigeration oil. The visual part can observe the depth of the oil suction pipe inserted into the refrigeration oil and the oil level height.

[0031] Further, the compressor housing includes an upper housing assembly and a lower housing assembly assembled together. The visualization part is a transparent glass provided in the lower half of the lower housing assembly, or both the upper housing assembly and the lower housing assembly are made of transparent materials; scale marks are also provided on the visualization part.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Through the setting of the visualization part, the oil quantity in the compressor housing and the depth of the oil suction pipe of the crankshaft inserted into the refrigeration oil can be directly and accurately observed, so as to identify the refrigeration oil filling quantity and the oil suction condition, which is convenient for the staff to timely discover the problems of the refrigeration oil and is conducive to the progress of the oil filling quantity identification test; 2. The method for identifying and judging the oil filling quantity of this compressor can accurately judge the oil filling quantity, fully consider the oil consumption problems of various parts and links during the operation of the compressor, enable the oil quantity of each part to be accurately controllable, not only meet the full lubrication requirements of the compressor, but also establish the optimal filling quantity of the compressor refrigeration oil through this method, greatly improving the operation reliability of the compressor and the economy of oil filling; 3. Through this method, abnormal conditions such as difficult starting of the compressor, too high housing temperature or even tripping caused by less oil in the compressor can be identified, abnormal mechanical dry friction sounds between parts caused by less oil or lack of oil in the compressor and increased power caused by poor motor cooling effect can be identified. At the same time, when the compressor oil is less, the temperature of the housing and the pump body becomes significantly higher. The high-temperature pump body heats the refrigerant, increasing the suction specific volume and reducing the suction volume. Through this method, abnormal conditions such as significantly longer low-temperature pulling time of the compressor and increased power consumption caused by less oil can be avoided, greatly reducing various abnormalities such as difficult starting, high housing temperature, and even increased power consumption of the compressor caused by lack of oil for cooling and lubrication; at the same time, once it is found that the compressor oil is less, the correct oil quantity can be supplemented in time through this structure, further improving the stability and reliability during the operation of the compressor; 4. Through this method, the oil quantity in the pump body with different cooling capacities can be obtained, generally about 40 - 50 ml, and the volume ratio of the different circulating oil quantities to the total oil quantity can also be obtained. Generally, the circulating oil quantity accounts for 14.4% - 15.7% of the total oil quantity; if the filling quantity of V3 is relatively large, after calculation, when the circulating oil quantity of the refrigeration oil exceeds 15.7%, the circulating oil quantity volume can be re-tested and established to make the circulating oil quantity return to 14.4% - 15.7% of the total oil quantity, or when the filling quantity is on the high side, at this time, the oil inlet depth of the oil suction pipe exceeds the optimal filling quantity scale line position, and the oil quantity can be continuously poured out to make the oil quantity return to the optimal filling quantity scale line position; 5. Through this method, the working state of the oil product during the operation of the compressor can be clearly seen. Once foaming occurs, the volume of the foam can be accurately identified through the scale line, and it can be determined whether the foaming performance is qualified. If the volume of the foam becomes larger and does not break, it indicates that the anti-foaming property of the refrigeration oil is unqualified, and an anti-foaming agent needs to be added. The feasibility of the added anti-foaming agent refrigeration oil can be verified again through this device and method, greatly improving the reliability of the compressor. Description of the Drawings

[0033] Figure 1 Structural schematic of the visualized compressor of the present invention Figure 1 ;

[0034] Figure 2 Structural schematic of the visualized compressor of the present invention Figure 2 ;

[0035] Figure 3 Structural schematic diagram of the bottom of the lower housing of the compressor of the present invention;

[0036] Figure 4 Internal schematic of the visualized compressor (cut lower housing assembly) of the present invention Figure 1 ;

[0037] Figure 5 Internal schematic of the visualized compressor (cut lower housing assembly) of the present invention Figure 2 ;

[0038] Figure 6 Schematic diagram of the compressor of the present invention connected to the refrigeration cycle system;

[0039] Figure 7 Another structural schematic diagram of the visualized compressor of the present invention;

[0040] Figure 8 is Figure 7 Structural schematic diagram of the lower housing of the compressor in

[0041] Figure 9 Another structural schematic diagram of the lower housing of the visualized compressor of the present invention;

[0042] Figure 10 is Figure 9 Cross-sectional structural schematic diagram of the lower housing of the compressor in

[0043] In the figure: 1. Compressor; 2. Upper housing assembly; 3. Lower housing assembly; 301. Lower housing cutting assembly; 4. Cylinder block; 5. Cylinder head assembly; 6. Connecting rod; 7. Crankshaft; 8. Motor; 801. Motor stator winding; 9. Compression spring; 10. Process pipe; 11. Suction pipe; 12. Exhaust pipe; 13. Oil guiding pipe; 14. Blowing pipe; 15. Power cord; 16. Sealed inflation joint; 17. Refrigeration oil; 18. Scale mark; 19. Sealing joint; 20. Inflation pipe; 21. Support pin; 22. Oil suction pipe; 23. First oil separator; 24. First oil storage tank; 25. Condenser; 26. Filter; 27. Throttling device; 28. Evaporator; 29. Second oil storage tank; 30. Second oil separator; 31. Cut-off valve; 32. First inflation valve; 33. Second inflation valve; 34. Transparent glass; 35. Window; 36. Positioning extension part. Detailed implementation mode

[0044] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the scope of protection of the present invention.

[0045] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 construed as a limitation of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0046] Combined Figures 1 to 5 As shown, the basic structure of the compressor is as follows: it includes an upper housing assembly 2 and a lower housing assembly 3. The pump body includes a cylinder block 4, a crankshaft 7, a connecting rod 6, a piston, and a cylinder head assembly 5, etc. The crankshaft 7 is installed in the shaft hole of the cylinder block 4. An oil suction pipe 22 is provided at the lower end of the crankshaft 7. A piston is installed in the cylinder hole of the cylinder block 4. The piston has a piston pin hole, and the piston pin is installed in the piston pin hole. The small hole of the connecting rod 6 is connected to the piston pin, and the large hole of the connecting rod 6 is connected to the eccentric shaft of the crankshaft 7; A motor is installed on the long shaft of the crankshaft 7. The motor rotor is sleeved on the crankshaft 7. The stator of the motor is installed on the stator surface of the cylinder block 4 and forms an installation gap with the rotor of the motor; A support pin 21 is arranged in the lower housing assembly 3. The pump body is connected to the support pin 21 through a compression spring 9. A process pipe 10, an exhaust pipe 12, and an intake pipe 11 are also connected to the outer periphery of the lower housing assembly.

[0047] A method for identifying and judging the oil injection amount of a compressor, the identification and judgment method includes the following steps:

[0048] Obtain the oil storage amount at the bottom of the lower housing of the compressor, denoted as V1;

[0049] Obtain the oil amounts contained in each moving pair of the pump body in the compressor and the motor stator winding (the motor stator winding generally includes an upper winding, a lower winding, and internal coils, etc.), denoted as V2;

[0050] Obtain the oil amount discharged from the compressor into the refrigeration cycle system, denoted as V3;

[0051] The total oil injection amount of the compressor is V, then V = V1 + V2 + V3.

[0052] The identification and judgment method for the oil injection amount of this compressor can accurately judge the oil injection amount, fully consider the oil consumption problems of various parts and links during the operation of the compressor, enable the oil amount of each part to be accurately controlled, not only meet the full lubrication requirements of the compressor, but also establish the optimal filling amount of the refrigeration oil of the compressor through this method, greatly improving the operation reliability of the compressor and the economy of oil filling.

[0053] Further, the method for obtaining the oil storage amount V1 is as follows: fabricate a visual lower housing assembly 3, install the pump body and the motor in the lower housing assembly 3, keep the pump body horizontal, and through the visual lower housing assembly 3, the oil suction pipe of the crankshaft in the pump body and the lower winding package of the motor stator can be observed;

[0054] Directly pour the refrigeration oil into the lower housing assembly 3, observe the oil level height and the depth of the oil suction pipe 22 of the crankshaft 7 in the pump body gradually entering the oil until the oil level has immersed 1 / 2 - 2 / 3 of the lower winding package 801 of the motor stator;

[0055] Gently pick up the pump body and observe whether the lower end ring of the rotor on the pump body is stained with oil, and ensure that there is no oil stain on the lower end ring of the rotor. Record the poured oil amount through a measuring cylinder. At this time, the oil amount can be approximately regarded as the oil storage amount V1 at the bottom of the lower housing.

[0056] Further, the lower housing assembly 3 is made of transparent tempered glass, or the lower housing assembly 3 is fabricated according to the following method:

[0057] Select a compressor lower housing, cut downward from the mating surface of the lower housing, cut off 2 / 3 - 3 / 4 to form a lower housing cutting assembly 301 with a height of 1 / 4 - 1 / 3 of the original lower housing height, so as to obtain an open - type compressor lower housing that can store oil at the bottom, and the situation of pouring the refrigeration oil into it can be observed. In this way, the oil inlet situation of the oil suction pipe and the motor lower winding package can be visually seen. Further, the lower winding package of the stator is completely removed (as Figure 5 shown) to more clearly test the oil inlet depth of the oil suction pipe and the distance between the lower end ring of the rotor and the oil level of the refrigeration oil.

[0058] Further, the method for obtaining the oil amount V2 is as follows: fabricate a visual upper housing assembly 2 and a lower housing assembly 3 (which can be made of transparent tempered glass), install the pump body and the motor in the upper housing assembly 2 and the lower housing assembly 3 according to the assembly requirements, and other required parts will also be assembled together to obtain an assembled compressor 1. That is to say, except that the housing of this compressor 1 is transparent, other parts are basically the same as those of a normal compressor, so as to more accurately reflect the actual oil amount of the compressor.

[0059] Lubricate the compressor through the process pipe 10 on the lower housing assembly 3, and observe the oil level height in real time through the transparent tempered glass until the oil level submerges 2 / 3 to 3 / 4 of the height of the lower winding package of the motor stator. Gently pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, and ensure that the lower end ring of the rotor does not touch the oil surface. Record the amount of oil V added to the compressor. A 。

[0060] Seal and block the process pipe 10 with the sealed inflation joint 16. Connect the suction pipe 11 on the lower housing assembly to the air hose, and connect the exhaust pipe 12 to the oil guiding pipe 13. The oil guiding pipe 13 is connected to a graduated cylinder; and connect a starter and a protector to the compressor's sealed terminal block, and connect the power cord 15 to the inserts of the protector and the starter.

[0061] Energize the compressor, and introduce dry air or nitrogen through the suction pipe 11. The pressure of the introduced gas is 0.04 - 0.08 MPa (shown by the pressure gauge). Energize for 2.5 hours, and record the volume of oil V in the graduated cylinder after the 2.5-hour test. b ; At the same time, let the compressor after energized operation stand still for 6 - 10 minutes, and pour out the remaining oil volume V in the compressor. c Then, for each moving pair of the pump body, such as the clearance between the piston and the cylinder bore, the clearance between the big and small holes of the connecting rod, etc., and for the motor stator winding package, the oil volume V2 = V A -V b -V c 。

[0062] Furthermore, the method for obtaining the oil volume V3 is as follows: fabricate a visual upper housing assembly 2 and lower housing assembly 3, and install the pump body and the motor into the upper housing assembly and the lower housing assembly according to the assembly requirements to obtain an assembled compressor. This step is basically the same as the above fabrication method;

[0063] Lubricate the compressor through the process pipe 10 on the lower housing assembly 3, and observe the oil level height in real time until the oil level submerges 2 / 3 to 3 / 4 of the height of the lower winding package of the motor stator. Pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, and ensure that the lower end ring of the rotor does not touch the oil surface. Record the amount of oil V added to the compressor. A ;

[0064] Connect the compressor 1 to the refrigeration cycle system, and an oil separator and an oil storage tank are provided in the refrigeration cycle system;

[0065] Vacuum the compressor, and charge an appropriate amount of refrigerant. Energize and run the compressor to let the refrigeration system operate stably for several hours. After the operation ends, pour the oil in the oil separator into the graduated cylinder, and record the oil volume V of the oil separator. d ;

[0066] Obtain the oil volume V in the oil storage tank.e , then the oil volume V3 = V d + V e .

[0067] Combined with Figure 6 As shown, the refrigeration cycle system includes a compressor 1, a first oil separator 23, a condenser 25, a filter 26, a throttling device 27, an evaporator 28, and a second oil separator 30 connected in sequence; a first oil storage tank 24 with a stop valve is provided between the first oil separator 23 and the condenser 25, and a second oil storage tank 29 with a stop valve is provided between the second oil separator 30 and the evaporator 28; a first charging valve 32 is provided between the filter 26 and the condenser 25, and a second charging valve 33 is provided between the throttling device 27 and the evaporator 28.

[0068] Specifically, the first oil separator 23 is connected at a distance of 30 cm from the exhaust pipe of the compressor 1, and the second oil separator 30 is connected at a distance of 20 cm from the suction pipe of the compressor. A first oil storage tank 24 is provided at the front end of the first oil separator 23, and a stop valve 31 is provided on the first oil storage tank 24. A first charging valve 32 is provided at a distance of 20 cm from the end of the condenser 25 at the end of the condenser. The first charging valve is located between the filter and the condenser and is connected by a thread. A second oil separator 30 is provided at a distance of 20 cm from the end of the evaporator 28 at the end of the evaporator. A second oil storage tank 29 is provided in front of the second oil separator 30, and a stop valve 31 is also provided on the second oil storage tank 29. A second charging valve 33 is provided at a distance of 10 cm from the end of the throttling device (such as a capillary tube) at the end of the throttling device. The second charging valve 33 is located between the throttling device 27 and the evaporator 28 and is connected by a thread.

[0069] Vacuum the compressor and charge an appropriate amount of refrigerant such as R600a. After the vacuuming of the compressor 1 is completed, the compressor is powered on and run. Open the first charging valve 32 and the second charging valve 33, and close the two stop valves 31. Let the refrigeration cycle system run stably for 3 - 3.5 hours. After the test, pour the oil in the first oil separator 23 and the second oil separator 30 into a graduated cylinder, and record the total oil volume V of the two oil separators d ;

[0070] Unscrew the thread at one end of the first inflation valve 32, open the stop valve on the first oil storage tank 24, connect nitrogen gas with a pressure of 0.8 - 1.0 MPa from the threaded end unscrewed from the first inflation valve 32, and use the high pressure of the nitrogen gas to blow the remaining oil in the high-pressure end of the refrigeration cycle system into the first oil storage tank 24; unscrew the thread at one end of the second inflation valve 33, open the stop valve on the second oil storage tank 29, connect nitrogen gas with a pressure of 0.8 - 1.0 MPa from the threaded end unscrewed from the second inflation valve 33, and use the high pressure of the nitrogen gas to blow the remaining oil in the low-pressure end of the refrigeration system into the second oil storage tank 29, and mix the oils in the first oil storage tank 24 and the second oil storage tank 29, heat them at a temperature of 40 - 50 °C for 5 minutes, and after heating, record the total oil volume V of the first oil storage tank 24 and the second oil storage tank 29 with a high-precision small measuring cylinder e ; then the oil volume V3 discharged from the compressor into the refrigeration cycle system is V d + V e , and in this way, the oil volume brought into the refrigeration cycle system can be obtained relatively accurately.

[0071] Furthermore, after connecting the compressor to the refrigeration cycle system and placing the refrigeration cycle system in a constant-temperature environment of 24 °C, evacuate the compressor. After the evacuation of the compressor is completed, fill it with an appropriate amount of refrigerant, and then power on the compressor to operate. Observe the oil stirring situation of the crankshaft in the pump body; if bubbles continuously emerge from the oil surface and do not disappear or even the volume of the bubbles becomes larger, it indicates that the anti-foaming performance of the compressor oil is unqualified, and there is a risk of difficult lubrication and poor sealing of the compressor; if no bubbles appear or the volume of the bubbles is small and the bubbles burst after foaming, it indicates that the anti-foaming performance of the compressor is qualified and the oil injection volume of the compressor is also qualified, meeting the lubrication and sealing requirements of the compressor.

[0072] Specifically, there is a blow hole at the bottom of the lower housing assembly 2 made of fully transparent toughened glass, and the blow hole is connected to a blow pipe 14 (such as Figure 2As shown, the process pipe 10 and the suction pipe 11 of the compressor are connected to the sealed inflation joint 16, the exhaust pipe 12 is connected to the sealed joint 19. The sealed inflation joint of the suction pipe 11 is connected to the external exhaust pipe, and the compressor is placed in a constant temperature environment of 24°C for 2 hours. After 2 hours of constant temperature, dry air is blown in from the blow pipe 14 for 5 minutes, and the air flow rate is 70 - 80 ml / min. It stagnates for 5 minutes, and the foaming volume is observed. The minute foaming is quantified through the scale line. After stabilizing for 10 minutes, the foaming amount is observed again. At this time, there are no bubbles, indicating that the foaming amount of the refrigerant oil at 24°C is qualified; then the compressor is placed in a constant temperature state of 94°C (it can also be placed in a constant temperature water bath environment), and dry air is blown in from the blow pipe 14 for 5 minutes, and the air flow rate is 70 - 80 ml / min. It stagnates for 5 minutes, and the foaming volume is observed. The foaming height is quantified through the scale line to obtain the foam volume. If the foam volume ≤ 30 ml, after stabilizing for 10 minutes, the foaming volume is observed again through the scale line. At this time, there are no bubbles or the bubbles have disappeared, indicating that the foaming amount of the refrigerant oil at 94°C is qualified, indicating that the anti-foaming performance of the compressor refrigerant oil is qualified. The compressor not only has a qualified oil volume and can meet the lubrication and sealing requirements of the compressor. Otherwise, it indicates that the anti-foaming performance of the compressor oil product is unqualified, and there is a risk of difficult lubrication and poor sealing of the compressor; if there are no bubbles or the bubble volume is very small, and the bubbles burst after foaming, it indicates that the anti-foaming performance of the compressor is qualified. See Table 1 below for details:

[0073] Table 1: Compressor Oil Foaming Test Table

[0074]

[0075] On the other hand, the present invention also provides an identification structure for the oil injection amount of the compressor. A visualization part is provided on the compressor housing. A pump body and a motor are provided inside the compressor housing. The lower end of the crankshaft in the pump body is provided with an oil suction pipe, and the oil suction pipe is connected to the refrigerant oil. The visualization part can observe the depth of the oil suction pipe inserted into the refrigerant oil and the oil level height.

[0076] Through the setting of the visualization part, the oil amount inside the compressor housing and the depth of the oil suction pipe of the crankshaft inserted into the refrigerant oil can be observed intuitively and accurately, so as to identify the refrigerant oil filling amount and the oil suction situation, which is convenient for the staff to timely discover problems with the refrigerant oil and is conducive to the progress of the oil injection amount identification test.

[0077] In some embodiments, as Figure 7 and Figure 8 shown, the visualization part is a window 35 provided in the lower half of the lower housing assembly 3. A transparent glass 34 is provided at the window 35, and the scale mark 18 is provided on the transparent glass 43. The lower housing assembly is provided with a positioning extension part 36 at the window 35, and the side of the transparent glass 34 is mounted on the positioning extension part 36 and sealed and fixed.

[0078] In some embodiments, as Figure 9 and Figure 10 shown, the lower housing assembly 3 includes an upper half of the lower housing and a lower half of the lower housing. The lower half of the lower housing is a transparent housing to form the visualization part, and the scale markings 18 are provided on the lower half of the lower housing. There is a concave-convex plug-in structure between the lower end surface of the upper half of the lower housing and the upper end surface of the lower half of the lower housing, and they are fixedly connected in a sealed manner.

[0079] To further elaborate on this identification and judgment method, a certain model of compressor is taken as an example for detailed description.

[0080] By determining the compressor displacement through the compressor cylinder bore diameter and the crankshaft eccentric position, a compressor with an R600a refrigerating capacity of 95W is obtained. As shown in the figure, starting from the lower housing stop surface of the compressor, 2 / 3 to 3 / 4 is cut off to form a lower housing cutting assembly with a height of 1 / 4 to 1 / 3 of the height of the main body lower housing. A support pin is welded at the bottom of the lower housing cutting assembly, and a spring support block is installed on the support pin. The spring support block is equipped with a compression spring. The pump body is placed on the compression spring and kept horizontal.

[0081] Alternatively, the pump body is placed on the lower housing assembly composed of fully transparent tempered glass, and the crankshaft oil suction pipe and the motor stator lower wire package in the pump body can be observed through the transparent tempered glass.

[0082] Pour the refrigeration oil directly into the lower housing assembly, observe the oil level height and the depth at which the crankshaft oil suction pipe in the pump body gradually enters the oil until the oil level has immersed 1 / 2 to 2 / 3 of the motor stator lower wire package; gently pick up the pump body and observe whether the lower end ring of the rotor on the pump body is oil-stained, and ensure that there is no oil stain on the lower end ring of the rotor. Record the amount of oil poured through a measuring cylinder. At this time, the amount of oil can be approximated as the oil storage volume V1 at the bottom of the lower housing, V1 = 55 ml.

[0083] Pour the oil of V1 back into the lower housing assembly, close the upper housing assembly, inject oil into the compressor through the process pipe, observe the oil level height through the transparent tempered glass until the oil level has immersed 2 / 3 to 3 / 4 of the height of the motor lower wire package. At the same time, pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, ensure that the lower end ring of the rotor does not contact the oil surface, and record the amount of oil poured into the inner housing of the compressor as V A = 95 ml.

[0084] Seal the process pipe with a sealing joint. Connect the suction pipe on the lower housing assembly to an air hose, connect the exhaust pipe to an oil guiding pipe, and the oil guiding pipe is connected to a measuring cylinder; and connect a starter and a protector to the compressor sealing terminal block, and connect the power supply wire to the protector and the starter inserts.

[0085] Energize the compressor and introduce dry air or nitrogen through the suction pipe. The pressure of the introduced gas is 0.04 - 0.08 MPa. Energize for 2.5 hours and record the volume V of the oil in the graduated cylinder after the 2.5-hour test. b = 5 ml; At the same time, let the compressor stand still for 6 - 10 minutes after energized operation, and pour out the remaining oil volume V in the compressor. c = 50 ml, then the oil volume V2 of each moving pair of the pump body, such as the clearance between the piston and the cylinder bore, the clearance between the big and small holes of the connecting rod, etc., and the stator winding of the motor is:

[0086] V2 = V A - V b - V c = 95 - 5 - 50 = 40 ml.

[0087] Furthermore, reselect a compressor with a cooling capacity of 95 W. After installing the same pump body and motor in place, place the pump body with the motor into a transparent housing and seal the upper and lower housings. Inject oil into the compressor through the process pipe. Observe the oil level height through the transparent tempered glass until the oil level submerges 2 / 3 - 3 / 4 of the height of the lower winding of the motor. At the same time, pick up the pump body to ensure whether the lower end ring of the rotor is immersed in oil or wetted by oil, and ensure that the lower end ring of the rotor does not touch the oil surface, and record the oil volume V poured into the inner housing of the compressor. A = 105 ml.

[0088] Connect the compressor to the refrigeration cycle system, evacuate the compressor, and charge an appropriate amount of refrigerant such as R600a. After the evacuation of the compressor is completed, energize the compressor to run. Open the first charging valve 1 and the second charging valve, and close the two stop valves to allow the refrigeration cycle system to run stably for 3 - 3.5 hours. After the test is completed, pour the oil in the first oil separator and the second oil separator into a graduated cylinder, and record the total oil volume V of the two oil separators. d = 14 ml.

[0089] Unscrew the thread at one end of the first charging valve, open the stop valve on the first oil storage tank, and introduce nitrogen at 0.8 - 1.0 MPa through the unscrewed thread end of the first charging valve. Use the high pressure of nitrogen to blow the remaining oil at the high-pressure end of the refrigeration cycle system into the first oil storage tank; Unscrew the thread at one end of the second charging valve, open the stop valve on the second oil storage tank, and introduce nitrogen at 0.8 - 1.0 MPa through the unscrewed thread end of the second charging valve. Use the high pressure of nitrogen to blow the remaining oil at the low-pressure end of the refrigeration system into the second oil storage tank, and mix the oils in the first oil storage tank and the second oil storage tank. Heat at a temperature of 40 - 50 °C for 5 minutes. After heating, record the total oil volume V of the first oil storage tank and the second oil storage tank with a high-precision small graduated cylinder. e ≈ 2 ml; Then the oil volume V3 discharged from the compressor into the refrigeration cycle system = V d +V e= 14 + 2 = 16 ml.

[0090] Then the total oil injection volume V of the compressor is V = V1 + V2 + V3 = 55 + 40 + 16 = 111 ml. Among them, the ratio of the circulating oil volume V3 discharged from the compressor into the refrigeration cycle system to the total oil volume is 14.4%.

[0091] Furthermore, select a compressor with an R600a refrigerating capacity of 165 W. According to the same method above, V1 = 112 ml, V2 = 45 ml, and V3 = 27 ml can be obtained for this compressor. Then the total oil volume V of this 165 - W compressor is V = 112 + 45 + 27 = 184 ml, and the V3 circulating oil volume accounts for 14.6% of the total oil volume.

[0092] Furthermore, select a compressor with an R600a refrigerating capacity of 200 W. According to the same method above, V1 = 116 ml, V2 = 50 ml, and V3 = 31 ml can be obtained for this compressor. Then the total oil volume V of this 200 - W compressor is V = 116 + 50 + 31 = 197 ml, and the V3 circulating oil volume accounts for 15.7% of the total oil volume.

[0093] It can be determined therefrom that the normal commercial refrigeration compressor's various moving pairs, such as the clearance between the piston and the cylinder bore, the clearance between the big and small holes of the connecting rod, etc., and the motor stator winding, etc., contain about 40 - 50 ml of oil. The circulating oil volume discharged from the compressor into the refrigeration cycle system accounts for 14.4% - 15.7% of the total oil volume. If it exceeds 15.7% through experiments, it indicates that the V3 of the compressor increases, which may warn that the oil filling volume becomes larger. Then, adjust the oil injection volume by obtaining data through this method to make the circulating oil volume of the oil return to the normal value. At the same time, through this device and method, it can also be visually found that the oil becomes abnormally more. After the oil becomes more, once the oil exceeds the lower end ring surface of the rotor, when the compressor starts and runs, there will be an obvious oil churning sound, and it can also be found through the transparent housing of this device that the rotor generates oil churning foam. Therefore, through this device and method, when the filling volume of the refrigeration oil is on the high side, at this time, the oil inlet depth of the oil suction pipe exceeds the best filling volume scale line position, and the oil volume is continuously poured out to make the oil volume return to the best filling volume scale line position.

[0094] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for identifying and judging the oil filling amount of a compressor, characterized in that: The identification and judgment method comprises the following steps: Obtain the oil volume at the bottom of the compressor lower shell, recorded as V1; Obtain the amount of oil contained in each moving pair of the pump body in the compressor and the stator winding of the motor, recorded as V2; The method for obtaining the oil volume V2 is as follows: making a visualized upper housing assembly and a lower housing assembly, installing a pump body and a motor in the upper housing assembly and the lower housing assembly according to assembly requirements, and obtaining an assembled compressor; Fill the compressor with oil through the process pipe on the lower housing assembly, and observe the oil level in real time until the oil level is 2 / 3 to 3 / 4 of the height of the lower stator winding of the motor. Pick up the pump body to ensure that the lower end ring of the rotor is immersed in oil or soaked in oil, and ensure that the lower end ring of the rotor does not touch the oil surface. Record the amount of oil added to the compressor V A ; The process pipe is blocked, the air intake pipe on the lower shell assembly is connected to the ventilation hose, the air exhaust pipe is connected to the oil introduction pipe, and the oil introduction pipe is connected to the measuring cylinder; Power on the compressor, introduce dry air or nitrogen from the suction pipe, and record the volume V of the oil in the measuring cylinder after a period of testing. b At the same time, let the compressor stand for 6 to 10 minutes after power-on, and pour out the remaining oil V in the compressor. c , then the oil volume V2=V A -V b -V c ; Obtain the amount of oil discharged from the compressor into the refrigeration cycle system, recorded as V3; The total oil injection volume of the compressor is V, then V=V1+V2+V3.

2. The method for identifying and judging the oil injection amount of a compressor according to claim 1, characterized in that: The method for obtaining the oil storage volume V1 is as follows: make a visualized lower housing assembly, install the pump body and the motor in the lower housing assembly, and keep the pump body level; Pour the refrigeration oil into the lower housing assembly, and observe the oil level and the depth of the oil suction pipe of the crankshaft in the pump body until the oil level has penetrated 1 / 2 to 2 / 3 of the lower winding package of the motor stator; Pick up the pump body and observe whether the lower end ring of the rotor on the pump body is stained with oil, and ensure that there is no oil stain on the lower end ring of the rotor. Record the amount of oil poured in. The amount of oil at this time is the oil storage volume V1 at the bottom of the lower shell.

3. The method for identifying and judging the oil injection amount of a compressor according to claim 2, characterized in that: The lower shell component is made of transparent tempered glass, or the lower shell component is made according to the following method: Select a compressor lower shell, cut downward from the stop plane of the lower shell, cut off 2 / 3~3 / 4 and form a lower shell cutting component with a height of 1 / 4~1 / 3 of the original lower shell height.

4. The method for identifying and judging the oil injection amount of a compressor according to claim 1, characterized in that: The method for obtaining the oil volume V3 is as follows: making a visualized upper housing assembly and a lower housing assembly, installing a pump body and a motor in the upper housing assembly and the lower housing assembly according to assembly requirements, and obtaining an assembled compressor; Fill the compressor with oil through the process pipe on the lower housing assembly, and observe the oil level in real time until the oil level is 2 / 3 to 3 / 4 of the height of the lower stator winding of the motor. Pick up the pump body to ensure that the lower end ring of the rotor is immersed in oil or soaked in oil, and ensure that the lower end ring of the rotor does not touch the oil surface. Record the amount of oil added to the compressor V A ; Connecting the compressor to a refrigeration cycle system, wherein the refrigeration cycle system is provided with an oil separator and an oil storage tank; The compressor is evacuated and filled with an appropriate amount of refrigerant. The compressor is powered on and the refrigeration system is allowed to run stably for several hours. After the operation is completed, the oil in the oil separator is poured into a measuring cylinder and the oil volume V in the oil separator is recorded. d ; Get the oil volume V in the oil reservoir e , then the oil volume V3=V d +V e .

5. The method for identifying and judging the oil injection amount of a compressor according to claim 4, characterized in that: The oil volume V in the oil reservoir e The method for obtaining is as follows: open the stop valve on the oil reservoir, use nitrogen to blow the oil remaining at the high-pressure end of the refrigeration cycle system into the oil reservoir; heat it at 40-50°C for several minutes, and after heating, record the oil volume V in the oil reservoir. e .

6. The method for identifying and judging the oil injection amount of a compressor according to claim 1, characterized in that: The refrigeration cycle system includes a compressor, a first oil separator, a condenser, a filter, a throttling device, an evaporator and a second oil separator which are connected in sequence; a first oil reservoir with a shut-off valve is provided between the first oil separator and the condenser, and a second oil reservoir with a shut-off valve is provided between the second oil separator and the evaporator; a first charging valve is provided between the filter and the condenser, and a second charging valve is provided between the throttling device and the evaporator.

7. The method for identifying and judging the oil injection amount of a compressor according to claim 1, characterized in that: After the compressor is connected to the refrigeration cycle system, the refrigeration cycle system is placed in a constant temperature environment, and the compressor is evacuated. After the evacuation is completed, the compressor is filled with a proper amount of refrigerant, the compressor is powered on and the crankshaft stirring oil in the pump body is observed; if bubbles continue to emerge from the oil surface, and the bubbles do not disappear or even become larger in size, it means that the anti-foaming performance of the compressor oil is unqualified, and the compressor is at risk of difficulty in lubrication and poor sealing; If no bubbles appear or the volume of the bubbles becomes smaller, and the bubbles burst after bubbling, it means that the anti-bubble performance of the compressor is qualified, the oil filling amount of the compressor is also qualified, and the lubrication and sealing requirements of the compressor are met.

8. The identification structure of the method for identifying and judging the compressor oil injection amount according to any one of claims 1 to 7, characterized in that: A visualization part is provided on the compressor housing, and a pump body and a motor are provided in the compressor housing. An oil suction pipe is provided at the lower end of the crankshaft in the pump body, and the oil suction pipe is connected to the refrigeration oil. The visualization part can observe the depth of the oil suction pipe inserted into the refrigeration oil and the oil level height.

9. The identification structure of the method for identifying and judging the compressor oil injection amount according to claim 8, characterized in that: The compressor housing includes an upper housing component and a lower housing component assembled together, the visualization part is a transparent glass arranged on the lower half of the lower housing component, or the upper housing component and the lower housing component are both made of transparent materials; the visualization part is also provided with a scale mark.

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