Helium compressor improved by using air conditioning scroll compression with enthalpy increasing function

Abstract

This invention discloses an improved helium compressor utilizing an air-conditioning scroll compressor with enthalpy-enhancing function. The compressor includes a heat exchanger and a scroll compressor with enthalpy-enhancing function. An oil drain port is located at the bottom of the scroll compressor. High-temperature lubricating oil separated by gravity at the bottom of the scroll compressor is discharged through the drain port to the heat exchanger for cooling. The cooled lubricating oil is divided into two paths: one path mixes with return gas and is sent to the suction port of the scroll compressor; the other path is sent to the intermediate-pressure chamber of the scroll disc inside the scroll compressor through an enthalpy-enhancing pipe. This invention diverts a portion of the cooled lubricating oil and sends it to the intermediate-pressure chamber of the scroll compressor through the enthalpy-enhancing pipe, where it mixes with helium at intermediate pressure before being compressed to high pressure. This reduces the motor power of the scroll compressor, lowers the heat generated by the scroll compressor, and improves system efficiency.

Description

Technical Field

[0001] This invention relates to a scroll helium compressor, specifically to a helium compressor improved using an air conditioning scroll compressor with enthalpy enhancement function, and more specifically, to modifying an air conditioning scroll compressor with liquid injection or vapor injection enthalpy enhancement function in the field of low-temperature heat pumps into a helium scroll compressor. Background Technology

[0002] Currently, there are no domestic manufacturers of helium scroll compressors in China; globally, only Hitachi and Emerson Copeland are capable of producing helium scroll compressors. Taking Hitachi as an example, its series of helium scroll compressors have an input power of 2-10kW. They feature a return gas flow that directly enters the scroll plate, allowing oil to enter the scroll plate compression chamber along with the helium, serving to cool, lubricate, and seal the scroll plate. After compression, the high-temperature, high-pressure oil and gas separate and accumulate at the bottom of the compressor. The high-temperature helium and high-temperature lubricating oil dissipate heat through an external heat exchanger under pressure differential.

[0003] Copeland Compressor Corporation has improved the scroll compressor for air conditioning equipment by adding a low-pressure oil-gas mixing channel at the scroll plate inlet. The oil-gas mixture is then fed into the scroll plate, and a high-pressure oil collection device is added to the high-pressure chamber. The high-temperature, high-pressure lubricating oil and helium are cooled in an external cooler. This provides a new approach to the production of helium scroll compressors. However, there are significant differences between scroll compression of helium and compression of air conditioning refrigerants. When compressing helium, due to its high adiabatic index, the temperature rise during compression is much greater than that of air conditioning refrigerants. High temperatures can cause lubricating oil deterioration, scroll plate and motor shutdown or damage.

[0004] Currently, the mature method to solve the problem of excessive compression heat generated during helium compression by the scroll compressor is to increase the oil injection volume in the compressor. This involves mixing helium with a large amount of lubricating oil and then sending the mixture into the low-pressure chamber of the scroll compressor in a standard air conditioner. The lubricating oil cools and lubricates the scroll compressor and helium, carrying away the compression heat and keeping the compression temperature within an acceptable range. The high-temperature lubricating oil and compressed helium are then extracted and cooled by an external cooler. However, the scroll compressor compresses the mixture of lubricating oil and helium from low pressure to high pressure. Because the compression chamber contains significantly more lubricating oil than in air conditioner operation, and liquids are difficult to compress, the power consumption of the motor driving the scroll compressor increases significantly, typically by 20%-40% compared to the rated output power of an air conditioner. This results in a significant increase in motor coil current and heat generation, causing the scroll compressor to deviate considerably from its air conditioner operating conditions during operation.

[0005] On the other hand, in order to improve the heating efficiency of ordinary scroll compressors, ordinary air conditioning scroll compressors have now been developed in the field of low-temperature heat pumps into high-efficiency scroll compressors that can increase enthalpy at the pressure chamber position in the scroll disk. Summary of the Invention

[0006] Purpose of the invention: The purpose of this invention is to provide an improved helium compressor that utilizes an air conditioning scroll compressor with enthalpy enhancement function, which can reduce power consumption and heat generation during the helium compression process of the air conditioning scroll compressor and improve the efficiency of the scroll compressor in compressing helium.

[0007] Technical solution: The helium compressor improved by using an air conditioning scroll compressor with enthalpy enhancement function as described in this invention includes a heat exchanger and a scroll compressor with enthalpy enhancement function. An oil drain port is provided at the bottom of the scroll compressor. The high-temperature lubricating oil separated by gravity at the bottom of the scroll compressor is discharged through the oil drain port to the heat exchanger for cooling. The cooled lubricating oil is divided into two paths. One path of lubricating oil is mixed with return gas and sent to the suction port of the scroll compressor. The other path of lubricating oil is sent to the medium-pressure chamber of the scroll plate inside the scroll compressor through the enthalpy enhancement pipe.

[0008] Furthermore, the return gas is pressure-stabilized by the buffer tank and then mixed with the aforementioned lubricating oil.

[0009] Furthermore, a third flow control device is provided on one of the lubricating oil pipelines, and a fourth flow control device is provided on the other lubricating oil pipeline.

[0010] Furthermore, a second solenoid valve is also provided on the lubricating oil pipeline. The second solenoid valve is normally closed and closes when the power is off to prevent the lubricating oil from flowing back into the buffer tank during compressor shutdown.

[0011] Furthermore, a third flow control device is provided on the pipeline of one lubricating oil, and a fourth flow control device is provided on the main pipeline of the two lubricating oil pipelines.

[0012] Furthermore, the flow control device employs a fixed-diameter throttling orifice, a variable-diameter throttling orifice, a capillary tube, or a combination of any type of throttling device.

[0013] Furthermore, the flow ratio of the one lubricating oil to the other lubricating oil is between 1:2 and 2:1.

[0014] Furthermore, the total oil circulation volume (L / min) controlled by the two-way lubricating oil flow control device is equal to the rated power (Q) of the vortex pressure tank.

[0015] Furthermore, the helium compressor also includes an oil-gas separator and an oil-gas adsorber. The high-temperature, high-pressure helium gas mixed with a large amount of lubricating oil, which is separated by gravity in the vortex compressor, is discharged from the exhaust port to the heat exchanger for cooling. Then, it is separated by the oil-gas separator. The separated helium gas is sent to the oil-gas adsorber to adsorb a very small amount of oil droplets and oil vapor, forming high-purity helium gas that is supplied to the cryogenic refrigerator for refrigeration expansion. The lubricating oil separated by the oil-gas separator is mixed with the return gas.

[0016] Furthermore, a high- and low-pressure bypass pipeline is provided between the buffer tank and the oil-gas separator. The high- and low-pressure bypass pipeline includes a check valve, a first solenoid valve and a second flow control device connected in parallel with the check valve, and the first solenoid valve and the second flow control device are connected in series.

[0017] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0018] This invention improves upon conventional air conditioning scroll compressors with enthalpy-increasing function in the field of low-temperature heat pumps. A portion of the cooled lubricating oil is diverted and sent into the intermediate-pressure chamber of the scroll compressor through an enthalpy-increasing pipe. It mixes with helium gas at intermediate pressure and then compresses it to high pressure. This reduces the motor power of the scroll compressor, lowers the heat generation of the scroll compressor, and makes the electrical parameters of the air conditioning scroll compressor when compressing helium gas closer to the air conditioning operating conditions, thereby improving system efficiency. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a helium compressor provided in an embodiment of this application;

[0020] Figure 2 This is a schematic diagram of the structure of another helium compressor provided in the embodiments of this application;

[0021] Figure 3 This is a schematic diagram of another helium compressor provided in the embodiments of this application. Detailed Implementation

[0022] The invention will now be further described with reference to the accompanying drawings.

[0023] Appendix Figures 1 to 3 The accompanying figure labels are as follows:

[0024] 1. Helium compressor; 2. Scroll compressor; 3. Suction port; 4. Enthalpy booster tube; 5. Shell; 6. Scroll disk; 7. Upper part of rotating shaft; 8. Motor rotor; 9. Motor stator coil; 10. Motor stator silicon steel sheet; 11. Oil level; 12. Rotating shaft; 13. Oil suction port; 14. Arrow; 15. Oil discharge port; 16. First pipeline; 17. Oil replenishment port; 18. Heat exchanger; 19. First temperature sensor; 20. Second temperature sensor; 21. Second pipeline; 22. Third pipeline; 23. Fourth pipeline; 24. First oil filter; 25. Fifth pipeline; 26. Third temperature sensor; 27. Sixth pipeline; 28. Oil-gas separator; 29, Seventh Pipeline; 30, Second Oil Filter; 31, First Flow Control Device; 32, Safety Valve; 33, Eighth Pipeline; 34, Oil-Gas Adsorber; 35, High and Low Pressure Bypass Pipelines; 36, Check Valve; 37, First Solenoid Valve; 38, Second Flow Control Device; 39, Pressure Sensor; 40, Ninth Pipeline; 41, Buffer Tank; 42, Tenth Pipeline; 43, Third Flow Control Device; 44, Fourth Flow Control Device; 45, Eleventh Pipeline; 46, Twelfth Pipeline; 47, Second Solenoid Valve; 48, First Pressure Gauge; 49, Second Pressure Gauge; 50, Low-Pressure Helium Inlet; 51, Gas Replenishment Port; 52, High-Pressure Helium Outlet.

[0025] Example 1

[0026] like Figure 1 As shown in the embodiment of this application, a helium compressor 1 is improved using an air conditioning scroll compressor with enthalpy-increasing function. The helium compressor 1 includes a scroll compressor 2, which is an improvement on a scroll compressor with enthalpy-increasing function from the field of low-temperature heat pumps. The main improvements include:

[0027] An oil drain port 15 is added to the bottom of the vortex pressure tank 2 to draw out the high-temperature lubricating oil separated by gravity from the bottom of the vortex pressure tank 2. The lubricating oil is cooled by heat exchange in the heat exchanger 18. After cooling, the lubricating oil is divided into two paths after passing through the first oil filter 24 and the fifth pipeline 25. One path of lubricating oil is mixed with the normal temperature low-pressure helium gas (return gas) in the eleventh pipeline 45 and the tenth pipeline 42 and then enters the suction port 3 of the vortex pressure tank 2. The other path of lubricating oil is sent to the medium pressure chamber of the vortex disk 6 through the twelfth pipeline 46 and the enthalpy increaser 4.

[0028] A third flow control device 43 is installed on the eleventh pipeline 45, and a fourth flow control device 44 is installed on the twelfth pipeline 46. The total oil circulation L / min controlled by the two flow control devices is equal to the rated power Q (W) of the vortex pressure tank. The flow ratio of lubricating oil in the eleventh pipe 45 and the twelfth pipe 46 is between 1:2 and 2:1.

[0029] More specifically, ambient temperature low-pressure helium gas enters helium compressor 1 through low-pressure helium inlet 50, and is sent to buffer tank 41 via ninth pipeline 40. After being pressurized in buffer tank 41, it enters tenth pipeline 42. The helium gas in tenth pipeline 42 mixes with cooled lubricating oil in eleventh pipeline 45 and enters suction port 3 of scroll compressor 2. The helium gas mixed with a large amount of lubricating oil is compressed in scroll plate 6 of scroll compressor 2. When compressed to intermediate pressure, another path sends cooled lubricating oil to the pressure chamber of scroll plate 6 via twelfth pipeline 46 and enthalpy increaser 4. This lubricating oil is then cooled and mixed with the helium gas containing a large amount of lubricating oil during the compression process. The mixed lubricating oil and helium gas are compressed from intermediate pressure to high pressure in scroll plate 6. Then, the mixture of helium gas and lubricating oil is discharged from the discharge port of scroll plate 6.

[0030] The discharged helium-lubricating oil mixture undergoes oil-gas separation under gravity within the high-pressure chamber of the scroll compressor 2. Lubricating oil droplets pass through the gaps between the motor rotor 8 and the motor stator coils 9, as well as the gap between the motor stator silicon steel sheet 10 and the casing 5 of the scroll compressor 2, ultimately depositing at the bottom of the scroll compressor 2 to form a relatively stable oil surface 11. As the lubricating oil passes through the motor in the scroll compressor 2, it absorbs some of the motor's heat, thus cooling the motor. The lubricating oil deposited at the bottom of the scroll compressor 2 is drawn in through the oil inlet 13 of the rotating shaft 12, and then travels along the direction of arrow 14 to the upper part 7 of the rotating shaft to lubricate the rotating mechanism of the scroll disk 6. The lubricating oil deposited at the bottom of the vortex pressure tank 2 is led out of the vortex pressure tank 2 through the oil drain port 15, and enters the heat exchanger 18 through the first pipeline 16 for heat exchange and cooling. The cooled lubricating oil is sent to the first oil filter 24 through the fourth pipeline 23 to filter out solid impurities in the lubricating oil. After filtration and cooling, the lubricating oil enters the fifth pipeline 25. Then the fifth pipeline 25 is divided into two paths. One path goes through the eleventh pipeline 45 and the third flow control device 43 to connect to the tenth pipeline 42. The other path goes through the twelfth pipeline 46 and the fourth flow control device 44 to connect to the enthalpy increaser 4 of the vortex pressure tank 2, completing the oil circulation.

[0031] The high-temperature, high-pressure helium gas separated by gravity in the vortex press 2 is discharged from the exhaust port of the vortex press 2 to the sixth pipe 27. A third temperature sensor 26 is installed on the sixth pipe 27 to detect whether the exhaust temperature of the vortex press 2 is normal. The high-temperature, high-pressure helium gas mixed with a large amount of lubricating oil is sent to the heat exchanger 18 through the sixth pipe 27 for heat exchange and further oil-gas separation. After being cooled by heat exchange, the room-temperature, high-pressure gas containing a large amount of lubricating oil enters the oil-gas separator 28 through the third pipe 22 for oil-gas separation. The separated pure helium gas enters the oil-gas adsorber 34 through the eighth pipe 33 to adsorb a very small amount of oil droplets and oil vapor, forming high-purity helium gas. The high-purity helium gas is discharged through the high-pressure helium gas outlet 52 and supplied to the cryogenic refrigerator for refrigeration expansion and work. The helium gas after work returns to the low-pressure helium gas inlet 50, completing the helium gas refrigeration cycle.

[0032] The lubricating oil separated by the oil-gas separator 28 is sent back to the tenth pipeline 42 through the seventh pipeline 29. The seventh pipeline 29 is equipped with a second oil filter 30 and a first flow control device 31.

[0033] A safety valve 32 and a second pressure gauge 49 are installed on the oil-gas separator 28. In addition, a high-low pressure bypass line 35 is provided between the buffer tank 41 and the oil-gas separator 28. The high-low pressure bypass line 35 includes a check valve 36, a first solenoid valve 37 connected in parallel with the check valve 36, and a second flow control device 38 connected in series with the first solenoid valve 37 and the second flow control device 38.

[0034] A pressure sensor 39, a gas supply port 51, and a first pressure gauge 48 are installed on the ninth pipeline 40. The pressure sensor 39 is used to monitor the return gas pressure value, and the gas supply port 51 is used to replenish helium.

[0035] The cooling medium of the heat exchanger 18 is sent into the heat exchanger 18 through the second pipeline 21. A second temperature sensor 20 is installed at the cooling inlet and a first temperature sensor 19 is installed at the cooling outlet.

[0036] An oil replenishment port 17 is installed on the first pipeline 16. Oil replenishment is performed on the system through the oil replenishment port 17 at the factory.

[0037] The flow control device described above uses a fixed-diameter throttling orifice, a variable-diameter throttling orifice, a capillary tube, or a combination of any type of throttling device.

[0038] Example 2

[0039] like Figure 2 As shown, the structure is basically the same as that of Example 1, except that:

[0040] The fourth flow control device 44 is installed on the fifth pipeline 25.

[0041] Example 3

[0042] like Figure 3 As shown, the structure is basically the same as that of Example 1, except that:

[0043] A second solenoid valve 47 is also installed on the eleventh pipeline 45. This second solenoid valve 47 is normally closed and closes when de-energized to prevent lubricating oil from flowing back into the buffer tank 41 through the tenth pipeline 42 during compressor shutdown.

[0044] To reduce power consumption and heat generation during the helium compression process of an air conditioning scroll compressor and improve the efficiency of helium compression, this invention utilizes an existing low-temperature heat pump scroll compressor with enthalpy enhancement function. A portion of the externally cooled lubricating oil is introduced into the intermediate-pressure chamber of the scroll plate via an enthalpy enhancer. This reduces the amount of lubricating oil compressed from the low-pressure chamber to the intermediate-pressure chamber, thereby reducing the power consumption of the scroll compressor. The function can meet the lubrication and cooling requirements of the scroll compressor.

Claims

1. A helium compressor improved using an air conditioning scroll compressor with enthalpy-increasing function, characterized in that, The system includes a heat exchanger (18) and a vortex pressure vessel (2) with enthalpy enhancement function. The vortex pressure vessel (2) has an oil drain port (15) at its bottom. High-temperature lubricating oil separated by gravity at the bottom of the vortex pressure vessel (2) is discharged through the oil drain port (15) to the heat exchanger (18) for cooling. The cooled lubricating oil is divided into two paths: one path mixes with return gas and is sent to the suction port (3) of the vortex pressure vessel (2); the other path is sent through the enthalpy enhancement pipe (4) to the medium-pressure chamber of the vortex disk (6) inside the vortex pressure vessel (2). The flow ratio of the first path to the second path of lubricating oil is... Between; helium mixed with lubricating oil is compressed in the vortex disk (6) of the vortex press (2). When compressed to the intermediate pressure, the cooled lubricating oil sent to the pressure chamber of the vortex disk (6) through the enthalpy increaser (4) is cooled and mixed with the helium containing a large amount of lubricating oil during the compression process. The mixed lubricating oil and helium are compressed from the intermediate pressure to the high pressure in the vortex disk (6).

2. The helium compressor according to claim 1, characterized in that, The return gas is stabilized by the buffer tank (41) and then mixed with the lubricating oil in the first channel.

3. The helium compressor according to claim 2, characterized in that, A third flow control device (43) is provided on one of the lubricating oil pipelines, and a fourth flow control device (44) is provided on the other lubricating oil pipeline.

4. The helium compressor according to claim 3, characterized in that, The pipeline of the lubricating oil is also equipped with a second solenoid valve (47). The second solenoid valve (47) is normally closed and closes when the power is off to prevent the lubricating oil from flowing back into the buffer tank (41) during the compressor shutdown process.

5. The helium compressor according to claim 2, characterized in that, A third flow control device (43) is provided on one of the lubricating oil pipelines, and a fourth flow control device (44) is provided on the main pipeline of the two lubricating oil pipelines.

6. The helium compressor according to any one of claims 3 to 5, characterized in that, The flow control device uses a fixed-diameter throttling orifice, a variable-diameter throttling orifice, a capillary tube, or a combination of any type of throttling device.

7. The helium compressor according to any one of claims 3 to 5, characterized in that, The total oil circulation volume (L / min) controlled by the two-way lubricating oil flow control device is equal to the rated power (Q) of the vortex pressure tank. .

8. The helium compressor according to claim 2, characterized in that, It also includes an oil-gas separator (28) and an oil-gas adsorber (34). The high-temperature and high-pressure helium gas mixed with a large amount of lubricating oil, which is separated by gravity in the vortex pressure pack (2), is discharged from the exhaust port to the heat exchanger (18) for cooling. Then it is separated by the oil-gas separator (28). The separated helium gas is sent to the oil-gas adsorber (34) to adsorb a very small amount of oil droplets and oil vapor, forming high-purity helium gas for the cryogenic refrigerator to perform refrigeration expansion work. The lubricating oil separated by the oil-gas separator (28) is mixed with the return gas.

9. The helium compressor according to claim 8, characterized in that, A high-low pressure bypass pipeline (35) is provided between the buffer tank (41) and the oil-gas separator (28). The high-low pressure bypass pipeline (35) includes a check valve (36), a first solenoid valve (37) connected in parallel with the check valve (36), and a second flow control device (38). The first solenoid valve (37) and the second flow control device (38) are connected in series.

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