Device for preventing oil from being emulsified in oil cavity of screw pump
By introducing an oil blowing and scraping mechanism into the screw pump, the problems of decreased lubrication performance and difficult maintenance caused by lubricating oil emulsification are solved, achieving efficient cleaning and sealing, and reducing equipment maintenance costs.
Patent Information
- Application Number
- CN202511480832.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-16
- Publication Date
- 2025-12-19
AI Technical Summary
The oil chamber of a screw pump is prone to lubricating oil emulsification, which leads to decreased lubrication performance, increased wear on bearings and rotors, and clogging of oil passages by emulsified sludge, affecting heat dissipation, causing equipment overheating, high maintenance costs and low efficiency. Ordinary oil discharge ports cannot completely remove residues from the chamber walls.
An oil emulsification device for an oil chamber of a screw pump was designed, comprising an oil blowing mechanism and an oil scraping mechanism. The device uses a pneumatic cylinder to drive a lifting plate to move a spray nozzle to remove residual oil film and impurities from the inner wall of the oil chamber. Combined with the rotation of the scraper, it achieves rapid oil discharge. A sealed chamber is added to isolate the vacuum chamber from the oil chamber, preventing the medium from contaminating the lubricating oil.
It effectively prevents lubricating oil emulsification, improves cleaning efficiency, reduces the difficulty of manual cleaning, ensures lubrication performance, avoids equipment overheating, and reduces maintenance costs.
Smart Images
Figure CN121162518A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of screw pump processing technology, and in particular to a screw pump oil emulsification device for preventing oil from entering the oil chamber. Background Technology
[0002] Screw pumps, as a type of positive displacement pump, are widely used in industries such as petroleum, chemical, food, and shipbuilding to transport high-viscosity media containing solid particles or easily emulsified media. Their core component, the helical rotor, relies on lubricating oil for lubrication and cooling when rotating at high speed to reduce friction and wear and ensure long-term stable operation.
[0003] Screw pumps often face the problem of lubricating oil emulsification in their oil chambers. The medium being pumped may seep into the oil chamber through mechanical seals or bearing clearances, mixing with the lubricating oil to form an emulsion. This reduces the viscosity of the lubricating oil, degrades its lubrication performance, and exacerbates wear on the bearings and rotor. Emulsified sludge can clog the oil passages, affecting heat dissipation and leading to overheating or even seizure of the equipment. Frequent lubricating oil replacements increase maintenance costs, and waste oil disposal is difficult. Furthermore, the oil chamber lacks an active cleaning function, requiring manual disassembly and cleaning of deposited emulsified sludge, resulting in low maintenance efficiency. Ordinary unloading ports cannot completely remove residual oil and impurities adhering to the chamber walls, easily leading to residual pollution. Summary of the Invention
[0004] The problem solved by this invention is to provide a screw pump oil chamber emulsification prevention device, which addresses the common problem of lubricating oil emulsification in screw pump oil chambers. The medium being pumped may seep into the oil chamber through mechanical seals or bearing clearances, mixing with the lubricating oil to form an emulsion. This leads to a decrease in lubricating oil viscosity, deterioration of lubrication performance, and accelerated wear of bearings and rotors. Emulsified sludge can clog oil passages, affecting heat dissipation and causing overheating or even seizure of the equipment. Frequent lubricating oil replacement increases maintenance costs, and waste oil disposal is difficult. Furthermore, the oil chamber lacks an active cleaning function, requiring manual disassembly and cleaning of deposited emulsified sludge, resulting in low maintenance efficiency. Ordinary unloading ports cannot completely remove residual oil and impurities adhering to the chamber walls, easily leading to residual pollution.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] An oil emulsification device for an oil-proof chamber of a screw pump includes a base, a pump body, a first housing, and a second housing. The pump body, the first housing, and the second housing are sequentially connected by bolts. Two helical rotors are rotatably mounted inside the pump body. A sealing cavity is formed between the first housing and the second housing. An oil cavity is formed inside the second housing. Two meshing rotating teeth are installed in the oil cavity of the two helical rotors. A first motor is mounted on the base, and the first motor is connected to the end of one of the helical rotors via a coupling. An oil blowing mechanism and an oil scraping mechanism are installed in the oil cavity.
[0007] Preferably, a pump cover is installed at the end of the pump body, one end of the spiral rotor is connected to the pump body through a first mechanical seal and a first sealed bearing, and the other end of the spiral rotor is connected to the first housing through a second mechanical seal and a second sealed bearing.
[0008] Preferably, the spiral rotor and the second housing are connected by an oil seal and a third sealed bearing, the second housing has a lubricating oil inlet, and the bottom of the second housing has an oil discharge port.
[0009] Preferably, the oil blowing mechanism includes a lifting plate installed on the first housing, a pneumatic cylinder is installed on the lifting plate, and the telescopic end of the pneumatic cylinder is connected to the top side of the first housing. An air passage is installed inside the lifting plate, which communicates with the first lifting pipe and the second lifting pipe, and the air passage is connected to an air pump through an air pipe.
[0010] Preferably, a first lifting pipe is installed on both sides of the middle part of the lifting plate, and a straight nozzle is installed at the bottom of the first lifting pipe inside the oil cavity, and the length of the straight nozzle is adapted to the distance between the two spiral rotors.
[0011] Preferably, a second lifting pipe is installed on both sides of the lifting plate, the bottom end of the second lifting pipe is connected to the sleeve, and the sleeve is elastically connected to both ends of the U-shaped nozzle. Several spray holes are opened on the outside of the straight nozzle, the sleeve and the U-shaped nozzle.
[0012] A wheel seat is installed in the middle of the U-shaped nozzle, and a guide wheel is installed on the wheel seat.
[0013] Preferably, a pipe ring is installed at the end of the U-shaped nozzle, an air inlet groove is opened at the end of the U-shaped nozzle, and a spring is fitted at the end of the U-shaped nozzle, with the spring connected to the pipe ring and the inner wall of the sleeve.
[0014] Preferably, the oil scraping mechanism includes a transmission box installed on the bottom side of the second housing, and a central oil hole is provided in the middle of the transmission box. An oil drain valve is installed at the bottom of the central oil hole and is connected to an oil drain pipe. An installation shaft is installed on the top side of the transmission box, and a rotating seat is installed at the top of the installation shaft inside the oil cavity. Several arc-shaped scrapers are installed at equal angles on the outer side of the rotating seat, and the bottom side of the arc-shaped scrapers contacts the bottom wall of the oil cavity.
[0015] Preferably, a synchronous pulley is installed at the bottom of the mounting shaft, and the two synchronous pulleys are connected by a synchronous belt. The output end of the second motor at the bottom of the transmission box is connected to one of the synchronous pulleys.
[0016] Preferably, the specific steps for using this device are as follows:
[0017] Step 1: Assemble the device. The first motor drives one of the screw rotors to rotate. The two screw rotors rotate through the gear transmission, so that the screw pump can work normally. The mechanical seal and oil seal are used to achieve the sealing of the device.
[0018] Step 2: Inject lubricating oil into the oil chamber. When the device is working, it will lubricate the rotating gear. The lubricating oil needs to be replaced regularly. Open the oil drain valve to drain the lubricating oil. At the same time, the second motor works, and the synchronous pulley and synchronous belt drive the rotating seat and the arc-shaped scraper to rotate. This can scrape the oil in the oil chamber towards the oil discharge port, and also scrape the impurities settled at the bottom of the oil chamber towards the oil discharge port.
[0019] Step 3: The lifting plate is lowered by the pneumatic cylinder. At this time, the air pump works, blowing high-pressure airflow obliquely downward from the nozzles of the straight nozzle, sleeve, and U-shaped nozzle towards the inner wall of the oil chamber. As the straight nozzle, sleeve, and U-shaped nozzle move downward, the lubricating oil and impurities adhering to the inner wall of the oil chamber move downward along the inner wall of the oil chamber. The guide wheel of the U-shaped nozzle moves along the arc-shaped inner wall at the end of the oil chamber. When the U-shaped nozzle moves down from the top of the oil chamber to the middle of the oil chamber, with the cooperation of the guide wheel, the stretched spring gradually contracts, driving the U-shaped nozzle to move closer to the end of the oil chamber in the sleeve. When the U-shaped nozzle moves down from the middle of the oil chamber to the bottom of the oil chamber, with the cooperation of the guide wheel, the spring is stretched again, driving the U-shaped nozzle to move closer to the middle of the oil chamber in the sleeve. During the horizontal descent of the U-shaped nozzle, the gap between the end of the U-shaped nozzle and the straight nozzle allows the spiral rotor to pass through. After the straight nozzle, sleeve, and U-shaped nozzle have completed the downward movement and oil blowing, they move back up to the initial position.
[0020] The beneficial effects of this invention are: by adding a sealed cavity between the oil cavity and the vacuum cavity of the pump body, the two cavities are isolated, preventing material from entering the oil cavity when the working medium in the vacuum cavity leaks out, thereby ensuring that the bearings and gears are not contaminated or damaged, and reducing the risk of the working medium contaminating the lubricating oil;
[0021] The pneumatic cylinder drives the lifting plate to move the straight nozzle and the U-shaped nozzle up and down. High-pressure airflow is sprayed through the nozzle to remove residual oil film and impurities from the inner wall of the oil chamber and prevent the accumulation of deposits. The guide wheel and spring work together to make the U-shaped nozzle automatically adjust its position on the arc-shaped inner wall of the oil chamber to ensure that the airflow covers the entire area and avoids the spiral rotor, thereby improving cleaning efficiency. The downward airflow pushes the oil and impurities to the unloading port for centralized discharge.
[0022] The second motor drives the arc-shaped scraper to rotate via a synchronous belt, simultaneously scraping away the oil and impurities deposited at the bottom of the oil chamber. Combined with the drain valve, this enables rapid oil drainage, reducing the difficulty of manual cleaning. The central oil hole and the drain pipe form a low-resistance oil drainage channel, which, together with the arc-shaped scraper action, enhances the thoroughness of oil drainage. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;
[0024] Figure 2 This is an overall sectional view of the present invention;
[0025] Figure 3 This is a schematic diagram of the oil blowing device of the present invention;
[0026] Figure 4 This is a schematic diagram of the first structure for installing the straight nozzle and U-shaped nozzle of the present invention;
[0027] Figure 5 This is a schematic diagram of the second structure for installing the straight nozzle and U-shaped nozzle of the present invention;
[0028] Figure 6 This is a schematic diagram of the mounting structure of the rotary seat and the arc-shaped scraper of the present invention;
[0029] Figure 7 This is a schematic diagram of the oil scraping mechanism of the present invention;
[0030] Figure 8 This is a schematic diagram of the internal structure of the transmission box of the present invention.
[0031] Legend:
[0032] 1. Base; 2. Pump body; 3. First housing; 4. Second housing; 5. First motor; 6. Helical rotor; 7. First mechanical seal; 8. First sealed bearing; 9. Second mechanical seal; 10. Second sealed bearing; 11. Sealing cavity; 12. Oil cavity; 13. Oil seal; 14. Third sealed bearing; 15. Rotary gear; 16. Lifting plate; 17. Pneumatic cylinder; 18. First lifting pipe; 19. Linear nozzle; 20. Second lifting pipe; 21. Sleeve; 22. U-shaped nozzle; 23. Wheel seat; 24. Guide wheel; 25. Nozzle; 26. Air inlet groove; 27. Pipe ring; 28. Spring; 29. Rotary seat; 30. Arc-shaped scraper; 31. Oil discharge port; 32. Transmission box; 33. Central oil hole; 34. Oil drain valve; 35. Oil drain pipe; 36. Mounting shaft; 37. Synchronous pulley; 38. Synchronous belt; 39. Second motor. Detailed Implementation
[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0034] Specific implementation examples are given below.
[0035] See Figures 1 to 8An oil emulsification device for an oil-proof chamber of a screw pump includes a base 1, a pump body 2, a first housing 3, and a second housing 4. The pump body 2, the first housing 3, and the second housing 4 are sequentially connected by bolts. Two helical rotors 6 are rotatably mounted inside the pump body 2. A sealing cavity 11 is formed between the first housing 3 and the second housing 4. An oil cavity 12 is formed inside the second housing 4. Two meshing rotating teeth 15 are installed in the oil cavity 12 on the two helical rotors 6. A first motor 5 is mounted on the base 1, and the first motor 5 is connected to the end of one of the helical rotors 6 by a coupling. A pump cover is installed at the end of the pump body 2. One end of the helical rotor 6 is connected to the pump... The body 2 is connected by a first mechanical seal 7 and a first sealed bearing 8, and the other end of the spiral rotor 6 is connected to the first housing 3 by a second mechanical seal 9 and a second sealed bearing 10. The spiral rotor 6 and the second housing 4 are connected by an oil seal 13 and a third sealed bearing 14. The second housing 4 has a lubricating oil inlet and an oil discharge port 31 at the bottom. A sealing cavity 11 is added between the oil cavity 12 and the vacuum cavity of the pump body 2 to isolate the two cavities and prevent the material from entering the oil cavity 12 when the working medium in the vacuum cavity leaks out, thereby ensuring that the bearings and gears are not contaminated and damaged, and reducing the risk of the working medium contaminating the lubricating oil.
[0036] An oil blowing mechanism and an oil scraping mechanism are installed inside the oil chamber 12.
[0037] The oil blowing mechanism includes a lifting plate 16 mounted on the first housing 3. A pneumatic cylinder 17 is mounted on the lifting plate 16, and the telescopic end of the pneumatic cylinder 17 is connected to the top side of the first housing 3. An air passage communicating with the first lifting pipe 18 and the second lifting pipe 20 is installed inside the lifting plate 16, and the air passage is connected to an air pump through an air pipe. The first lifting pipe 18 is installed on both sides of the middle part of the lifting plate 16, and a straight nozzle 19 is installed at the bottom end of the first lifting pipe 18 in the oil chamber 12. The length of the straight nozzle 19 is adapted to the distance between the two spiral rotors 6. The second lifting pipe 20 is installed on both sides of both ends of the lifting plate 16. The bottom end of the second lifting pipe 20 is connected to the sleeve 21, and the sleeve 21 is elastically connected to both ends of the U-shaped nozzle 22. Several openings are provided on the outer sides of the straight nozzle 19, the sleeve 21, and the U-shaped nozzle 22. The nozzle 25 has a wheel seat 23 installed in the middle of the U-shaped nozzle 22, and a guide wheel 24 is installed on the wheel seat 23. A pipe ring 27 is installed at the end of the U-shaped nozzle 22, and an air inlet groove 26 is opened at the end of the U-shaped nozzle 22. A spring 28 is fitted at the end of the U-shaped nozzle 22, and the spring 28 is connected to the pipe ring 27 and the inner wall of the sleeve 21. The pneumatic cylinder 17 drives the lifting plate 16 to move the straight nozzle 19 and the U-shaped nozzle 22 up and down. High-pressure airflow is sprayed through the nozzle 25 to remove residual oil film and impurities from the inner wall of the oil chamber 12 and avoid the accumulation of deposits. The guide wheel 24 and the spring 28 cooperate to make the U-shaped nozzle 22 automatically adjust its position on the arc-shaped inner wall of the oil chamber 12 to ensure that the airflow fully covers the oil and avoids the spiral rotor 6, thereby improving the cleaning efficiency. The downward airflow pushes the oil and impurities to the unloading port 31 for centralized discharge.
[0038] The oil scraping mechanism includes a transmission box 32 mounted on the bottom side of the second housing 4, with a central oil hole 33 in the middle of the transmission box 32. An oil drain valve 34 is installed at the bottom of the central oil hole 33 and is connected to an oil drain pipe 35. A mounting shaft 36 is mounted on the top side of the transmission box 32, and a rotating seat 29 is mounted at the top of the mounting shaft 36 inside the oil cavity 12. Several arc-shaped scrapers 30 are mounted at equal angles on the outer side of the rotating seat 29, with the bottom sides of the arc-shaped scrapers 30 contacting the bottom wall of the oil cavity 12. The bottom end of the mounting shaft 36... A synchronous pulley 37 is installed, and the two synchronous pulleys 37 are connected by a synchronous belt 38. The output end of the second motor 39 at the bottom of the transmission box 32 is connected to one of the synchronous pulleys 37. The second motor 39 drives the arc-shaped scraper 30 to rotate through the synchronous belt 38, and simultaneously scrapes away the oil and impurities deposited at the bottom of the oil chamber 12. Combined with the oil drain valve 34, it can quickly drain oil and reduce the difficulty of manual cleaning. The central oil hole 33 and the oil drain pipe 35 form a low-resistance oil drain channel, which, together with the action of the arc-shaped scraper 30, improves the thoroughness of oil draining.
[0039] Working principle: The device is assembled, and the first motor 5 drives one of the spiral rotors 6 to rotate. The rotation of both spiral rotors 6 is achieved through the transmission of the rotating gear 15, enabling the screw pump to operate normally. Mechanical seals and oil seals 13 ensure the sealing of the device. Lubricating oil is injected into the oil chamber 12, which lubricates the rotating gear 15 during operation. The lubricating oil needs to be replaced periodically. The oil drain valve 34 is opened to drain the lubricating oil. Simultaneously, the second motor 39 operates, and the synchronous pulley 37 and synchronous belt 38 drive the rotation of the rotating base 29 and the arc-shaped scraper 30. This scrapes the oil in the oil chamber 12 towards the discharge port 31 and also scrapes impurities settled at the bottom of the oil chamber 12 towards the discharge port 31. The pneumatic cylinder 17 drives the lifting plate 16 to descend. At this time, the air pump operates, blowing a high-pressure airflow obliquely downwards from the nozzles 25 of the straight nozzle 19, sleeve 21, and U-shaped nozzle 22 towards the inner wall of the oil chamber 12. As the straight nozzle 19, sleeve 21, and U-shaped nozzle 22 move downwards, the lubricating oil and impurities adhering to the inner wall of the oil chamber 12 move downwards along the inner wall of the oil chamber 12. The guide wheel 24 of the U-shaped nozzle 22 moves along the arc-shaped inner wall at the end of the oil chamber 12. When the U-shaped nozzle 22 moves from the top of the oil chamber 12 to the middle of the oil chamber 12, with the cooperation of the guide wheel 24, the stretched spring 28 gradually contracts, driving the U-shaped nozzle 22 to move closer to the end of the oil chamber 12 within the sleeve 21. When the U-shaped nozzle 22 moves down from the middle of the oil chamber 12 to the bottom of the oil chamber 12, with the cooperation of the guide wheel 24, the spring 28 is stretched again, which drives the U-shaped nozzle 22 to move closer to the middle of the oil chamber 12 within the sleeve 21. During the translational descent of the U-shaped nozzle 22, the gap between the end of the U-shaped nozzle 22 and the straight nozzle 19 facilitates the passage of the spiral rotor 6. After the straight nozzle 19, sleeve 21 and U-shaped nozzle 22 have completed the downward movement of oil blowing, they move up again to the initial position.
[0040] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A screw pump oil emulsification device for preventing oil condensation in the oil chamber, characterized in that, The pump body includes a base (1), a pump body (2), a first housing (3), and a second housing (4). The pump body (2), the first housing (3), and the second housing (4) are connected in sequence by bolts. Two spiral rotors (6) are rotatably installed inside the pump body (2). A sealing cavity (11) is provided between the first housing (3) and the second housing (4). An oil cavity (12) is provided inside the second housing (4). Two meshing rotating teeth (15) are installed in the oil cavity (12) of the two spiral rotors (6). A first motor (5) is installed on the base (1), and the first motor (5) is connected to the end of one of the spiral rotors (6) by a coupling. An oil blowing mechanism and an oil scraping mechanism are installed in the oil cavity (12).
2. The oil emulsification device for the oil chamber of a screw pump according to claim 1, characterized in that, The pump body (2) is equipped with a pump cover at one end. One end of the spiral rotor (6) is connected to the pump body (2) through a first mechanical seal (7) and a first sealed bearing (8), and the other end of the spiral rotor (6) is connected to the first housing (3) through a second mechanical seal (9) and a second sealed bearing (10).
3. The oil emulsification device for the oil chamber of a screw pump according to claim 2, characterized in that, The spiral rotor (6) and the second housing (4) are connected by an oil seal (13) and a third sealed bearing (14). The second housing (4) has a lubricating oil inlet and an oil discharge port (31) at the bottom.
4. The oil emulsification device for the oil chamber of a screw pump according to claim 3, characterized in that, The oil blowing mechanism includes a lifting plate (16) installed on the first housing (3), a pneumatic cylinder (17) is installed on the lifting plate (16), and the telescopic end of the pneumatic cylinder (17) is connected to the top side of the first housing (3). An air passage is installed inside the lifting plate (16) that communicates with the first lifting pipe (18) and the second lifting pipe (20), and the air passage is connected to the air pump through an air pipe.
5. The oil emulsification device for the oil chamber of a screw pump according to claim 4, characterized in that, The lifting plate (16) has a first lifting pipe (18) installed on both sides of the middle part, and the bottom end of the first lifting pipe (18) is located in the oil chamber (12) and a straight nozzle (19) is installed thereon, and the length of the straight nozzle (19) is adapted to the distance between the two spiral rotors (6).
6. The oil emulsification device for the oil chamber of a screw pump according to claim 5, characterized in that, The lifting plate (16) is equipped with a second lifting pipe (20) on both sides. The bottom end of the second lifting pipe (20) is connected to the sleeve (21), and the sleeve (21) is elastically connected to both ends of the U-shaped nozzle (22). Several spray holes (25) are opened on the outside of the straight nozzle (19), the sleeve (21) and the U-shaped nozzle (22). A wheel seat (23) is installed in the middle of the U-shaped nozzle (22), and a guide wheel (24) is installed on the wheel seat (23).
7. The oil emulsification device for the oil chamber of a screw pump according to claim 6, characterized in that, The U-shaped nozzle (22) is equipped with a pipe ring (27) at its end, and an air inlet groove (26) is opened at the end of the U-shaped nozzle (22). A spring (28) is fitted at the end of the U-shaped nozzle (22), and the spring (28) is connected to the pipe ring (27) and the inner wall of the sleeve (21).
8. The oil emulsification device for the oil chamber of a screw pump according to claim 7, characterized in that, The oil scraping mechanism includes a transmission box (32) installed on the bottom side of the second housing (4), and a central oil hole (33) is provided in the middle of the transmission box (32). An oil drain valve (34) is installed at the bottom of the central oil hole (33), and the oil drain valve (34) is connected to the oil drain pipe (35). An installation shaft (36) is installed on the top side of the transmission box (32), and a rotating seat (29) is installed at the top of the installation shaft (36) inside the oil cavity (12). Several arc-shaped scrapers (30) are installed at equal angles on the outer side of the rotating seat (29), and the bottom side of the arc-shaped scrapers (30) is in contact with the bottom wall of the oil cavity (12).
9. The oil emulsification device for the oil chamber of a screw pump according to claim 8, characterized in that, The mounting shaft (36) is equipped with a synchronous pulley (37) at its bottom end, and the two synchronous pulleys (37) are connected by a synchronous belt (38). The output end of the second motor (39) at the bottom of the transmission box (32) is connected to one of the synchronous pulleys (37).
10. The oil emulsification device for the oil chamber of a screw pump according to claim 9, characterized in that, The specific steps for using this device are as follows: Step 1: Assemble the device. Drive one of the spiral rotors (6) to rotate through the first motor (5). The two spiral rotors (6) rotate through the transmission of the rotating gear (15) to achieve normal operation of the screw pump. The device is sealed through the mechanical seal and oil seal (13). Step 2: Lubricating oil is injected into the oil chamber (12). When the device is working, it lubricates the rotating gear (15). The lubricating oil needs to be replaced regularly. Open the drain valve (34) to drain the lubricating oil. At the same time, the second motor (39) works, and the synchronous pulley (37) and synchronous belt (38) drive the rotating seat (29) and the arc-shaped scraper (30) to rotate. This can scrape the oil in the oil chamber (12) toward the oil discharge port (31) and scrape the impurities settled at the bottom of the oil chamber (12) toward the oil discharge port (31). Step 3: The lifting plate (16) is lowered by the pneumatic cylinder (17). At this time, the air pump works, blowing a high-pressure airflow obliquely downward from the nozzles (25) of the straight nozzle (19), sleeve (21) and U-shaped nozzle (22) to the inner wall of the oil chamber (12). As the straight nozzle (19), sleeve (21) and U-shaped nozzle (22) move downward, the lubricating oil and impurities adhering to the inner wall of the oil chamber (12) move downward along the inner wall of the oil chamber (12). The guide wheel (24) of the U-shaped nozzle (22) moves along the arc-shaped inner wall at the end of the oil chamber (12). When the U-shaped nozzle (22) moves from the top of the oil chamber (12) to the middle of the oil chamber (12), with the cooperation of the guide wheel (24), The stretched spring (28) gradually contracts, causing the U-shaped nozzle (22) to move closer to the end of the oil chamber (12) within the sleeve (21). When the U-shaped nozzle (22) moves down from the middle of the oil chamber (12) to the bottom of the oil chamber (12), with the cooperation of the guide wheel (24), the spring (28) is stretched again, causing the U-shaped nozzle (22) to move closer to the middle of the oil chamber (12) within the sleeve (21). During the translational descent of the U-shaped nozzle (22), the gap between the end of the U-shaped nozzle (22) and the straight nozzle (19) facilitates the passage of the spiral rotor (6). After the straight nozzle (19), sleeve (21) and U-shaped nozzle (22) have completed the oil blowing process, they move up again to the initial position.