Vacuum pump seal structure

Abstract

The utility model discloses a vacuum pump sealing structure, aims at solving the deficiency that particulate matter enters the sealing surface when vacuum pump is running, influences the sealing effect. The utility model discloses one side of vacuum pump sets up side cover and back cover, and the oil cavity is formed between side cover and back cover, installs the shaft and bearing seat on the side cover, installs the bearing between bearing seat and the shaft, installs the labyrinth seal ring and the shaft sleeve on the shaft, and the shaft sleeve is on the labyrinth seal ring and the bearing inner race between, installs the sealing lip between the shaft sleeve and bearing seat, sets up a plurality of circles of the labyrinth ring groove on the side of labyrinth seal ring, sets up a plurality of circles of the labyrinth convex ring on the side cover, and the labyrinth convex ring is inserted with the labyrinth ring groove. The vacuum pump sealing structure can block the particulate matter, avoid the sealing lip and the contact of particulate matter, improve the sealing effect, and be favorable to prolonging the service life of sealing element.

Description

Technical Field

[0001] This utility model relates to the field of vacuum pump technology, and more specifically, to a vacuum pump sealing structure. Background Technology

[0002] Sealing technology is widely used in mechanical equipment such as vacuum pumps, especially in chemical industries where there are particulate materials, liquids, or corrosive media. Sealing technology directly affects the service life of mechanical equipment. Currently, ordinary oil seals have the following shortcomings: 1. Particulate media can enter the friction surface, quickly damaging the seal; 2. The sublimated gelatinous substance from solvent-containing media can accumulate on the shaft and creep axially to the sealing surface, damaging the seal; 3. Sometimes, instantaneous high pressure and liquid media impact the seal, causing seal damage and allowing liquid to enter the oil chamber, emulsifying the lubricating oil and causing bearing failure; 4. Leaking lubricating oil can contaminate materials. Chinese patent application number 2024223899302 discloses an oil-sealed vacuum pump with leak-proof design. By setting up an oil return structure, oil leaking from the pump chamber returns to the pump chamber under negative pressure through the oil return channel, thereby avoiding or reducing the flow of leaked oil from the pump chamber to the external environment. However, the oil seal effect is not ideal; the gelatinous substance from the sublimation of solvent-containing media can accumulate on the shaft and creep axially to the sealing surface, damaging the seal. Utility Model Content

[0003] To overcome the above shortcomings, this utility model provides a vacuum pump sealing structure that can block particulate matter, improve the sealing effect, and help extend the service life of the sealing components.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a vacuum pump sealing structure, wherein a side cover and a rear cover are provided on one side of the vacuum pump, forming an oil cavity between the side cover and the rear cover, a rotating shaft and a bearing seat are installed on the side cover, a bearing is installed between the bearing seat and the rotating shaft, a labyrinth sealing ring and a bushing are installed on the rotating shaft, the bushing is positioned between the labyrinth sealing ring and the inner ring of the bearing, a sealing lip is installed between the bushing and the bearing seat, a number of labyrinth ring grooves are provided on the side of the labyrinth sealing ring, a number of labyrinth ring protrusions are provided on the side cover, and the labyrinth ring protrusions are inserted into the labyrinth ring grooves.

[0005] The labyrinth seal ring and side cover form a non-contact labyrinth-shaped cavity through the cooperation of the labyrinth ring groove and the labyrinth convex ring. This blocks the path of harmful media, especially particulate contaminants, from entering along the axial direction of the shaft. Harmful media diffuse radially, making it difficult for them to accumulate on the shaft. This effectively protects the sealing lip, which serves as the main seal, improving sealing performance and extending its service life. The bearing housing facilitates bearing installation and sealing lip installation. The bushing provides positioning for the bearing.

[0006] Preferably, the bearing housing is provided with a mounting groove, and a raised ring is provided at the bottom of the mounting groove. The bearing is fitted into the mounting groove, and the outer ring of the bearing rests on the raised ring.

[0007] The mounting slot facilitates bearing installation, and the convex ring provides excellent positioning for the bearing's outer ring.

[0008] Preferably, a cooling channel is provided inside the side cover.

[0009] Coolant is introduced into the cooling channel to cool the side cover, thereby quickly removing the frictional heat of the sealing and lubrication system, improving the operating conditions, and thus increasing the service life of the sealing system, which can generally be extended by 10-12 months.

[0010] Preferably, a bearing cap is fastened to the outer end of the bearing housing, and the bearing cap presses onto the outer ring of the bearing.

[0011] The bearing cap provides axial positioning for the bearing.

[0012] Preferably, the sealing lip includes an annular body, an annular front lip, and an annular rear lip. The annular front lip bends forward and fits tightly against the bushing, and the annular rear lip bends backward and fits tightly against the bushing.

[0013] The sealing performance of the sealing lip is greatly improved by setting an annular front lip and an annular rear lip.

[0014] Preferably, a bearing washer is installed between the bushing and the inner ring of the bearing.

[0015] Bearing washers provide axial positioning for bearings.

[0016] Preferably, a sealing ring is installed between the bearing washer and the bushing.

[0017] The sealing ring improves the sealing performance of the connection.

[0018] Preferably, the radial clearance between the labyrinth groove and the labyrinth convex ring is 0.15-0.25 mm.

[0019] The radial clearance is set in the range of 0.15-0.25mm, which can block most of the dirt, especially crystalline particles, making it difficult for harmful media to come into contact with the sealing lip.

[0020] Preferably, a pressure ring and a limiting ring are installed at the end of the shaft. The pressure ring is pressed between the inner ring of the bearing and the limiting ring, and the limiting ring is fixedly connected to the shaft.

[0021] The pressure ring and the limiting ring provide axial positioning for the inner ring of the bearing.

[0022] Preferably, the bushing is provided with a radially outward extending barrier disk, the barrier disk is provided with several barrier protrusions, and the bearing housing is provided with several barrier ring grooves, with the barrier protrusions and barrier ring grooves being inserted into each other.

[0023] The baffle plate on the bushing blocks impurities in the oil on the other side of the sealing lip, preventing residual impurities in the oil from contacting the sealing lip.

[0024] Compared with the prior art, the beneficial effects of this utility model are: (1) the vacuum pump sealing structure can block particulate matter, avoid contact between the sealing lip and particulate matter, improve the sealing effect, and help extend the service life of the sealing component; (2) coolant is introduced into the cooling channel to cool the side cover, so that the frictional heat of the sealing and lubrication system is quickly carried away, improve the working conditions, and thus improve the service life of the sealing system. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the present invention.

[0026] Figure 2 This is a partial enlarged view of the bearing seat position in Embodiment 1 of this utility model.

[0027] Figure 3 This is a partial enlarged view of the bearing seat position in Embodiment 2 of this utility model.

[0028] In the diagram: 1. Side cover, 2. Rear cover, 3. Oil chamber, 4. Pump housing, 5. Pump cavity, 6. End cover, 7. Vacuum pump, 8. Shaft, 9. Bearing housing, 10. Bearing, 11. Labyrinth seal ring, 12. Shaft sleeve, 13. Shaft shoulder, 14. Sealing lip, 15. Labyrinth ring groove, 16. Labyrinth ring convex ring, 17. Connecting hole, 18. Mounting groove, 19. convex ring, 20. Bearing gland, 21. Elastic pad 22. Plate, 23. Slot, 24. Mounting hole, 25. Flange, 26. Extension ring, 27. Labyrinth disc, 28. Bearing washer, 29. Sealing ring, 30. Recessed groove, 31. Pressure ring, 32. Limiting ring, 33. Annular body, 34. Annular front lip, 35. Annular rear lip, 36. Annular rib, 37. Cooling channel, 38. Barrier disc, 39. Barrier ring groove. Detailed Implementation

[0029] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings: Example 1: A vacuum pump sealing structure (see...) Figure 1 , Figure 2A side cover 1 and a rear cover 2 are provided on one side of the vacuum pump 7, forming an oil chamber 3 between the side cover 1 and the rear cover 2. The vacuum pump 7 includes a pump housing 4, within which a pump chamber 5 is provided. An end cover 6 is connected to the front end of the pump housing 4, and the side cover 1 is connected to the rear end of the pump housing 4. The rear cover 2 is securely connected to the side cover 1. A rotating shaft 8 and a bearing seat 9 are installed on the side cover 1. A bearing 10 is installed between the bearing seat 9 and the rotating shaft 8. One end of the rotating shaft 8 is connected to the end cover 6, and the other end of the rotating shaft 8 is connected to the side cover 1.

[0030] A labyrinth seal ring 11 and a bushing 12 are installed on the rotating shaft 8. The bushing 12 rests between the labyrinth seal ring 11 and the inner ring of the bearing 10. A shoulder 13 is provided on the rotating shaft 8. One end of the labyrinth seal ring 11 rests on the shoulder 13, and the other end rests on the end of the bushing 12. A sealing lip 14 is installed between the bushing 12 and the bearing housing 9. The sealing lip 14 is made of polytetrafluoroethylene (PTFE), which is resistant to high temperatures and corrosion and has a long service life. Several labyrinth seal ring grooves 15 are provided on the side of the labyrinth seal ring 11, and several labyrinth convex rings 16 are provided on the side cover 1. The labyrinth convex rings 16 are inserted into the labyrinth seal ring grooves 15. The radial clearance between the labyrinth seal ring grooves 15 and the labyrinth convex rings 16 is 0.15-0.25 mm. The radial clearance is set within the range of 0.15-0.25 mm, which can block most of the dirt, especially crystalline particles, making it difficult for harmful media to come into contact with the sealing lip 14.

[0031] A mounting groove 18 is provided on the bearing housing 9, and a raised ring 19 is provided at the bottom of the mounting groove 18. The bearing 10 is fitted into the mounting groove 18, with the outer ring of the bearing 10 resting on the raised ring 19. A bearing cap 20 is fastened to the outer end of the bearing housing 9, and the bearing cap 20 presses against the outer ring of the bearing 10. An elastic washer 21 is installed between the bearing cap 20 and the outer ring of the bearing 10. The axial positioning of the outer ring of the bearing 10 is achieved through the setting of the raised ring 19 and the bearing cap 20, ensuring the stability and reliability of the bearing 10 installation.

[0032] Two shafts 8 are provided. Two grooves 22 corresponding to the shafts 8 are provided on the side cover 1. Mounting holes 23 are provided at the bottom of the grooves 22. The bearing seat 9 is fastened to the open end of the groove 22. The end of the bearing seat 9 is provided with a flange 24, which presses against the end face of the side cover 1 for positioning. A gap is provided between the bearing seat 9 and the bottom of the groove 22.

[0033] An extension ring 25 is provided on the labyrinth sealing ring 11. The extension ring 25 is installed between the inner wall of the mounting hole 23 and the outer wall of the rotating shaft 8, with the end of the extension ring 25 abutting against the shoulder 13 of the rotating shaft 8. The shoulder 13 of the rotating shaft 8 is close to the end face of the side cover 1. A labyrinth disk 26 extending radially outward is provided on the labyrinth sealing ring 11, and a labyrinth ring groove 15 is provided on the side of the labyrinth disk 26. A labyrinth convex ring 16 is provided on the bottom surface of the recess 22.

[0034] A bearing washer 27 is installed between the bushing 12 and the inner ring of the bearing 10, and a sealing ring 28 is installed between the bearing washer 27 and the bushing 12. The bearing washer 27 provides axial positioning for the bearing 10. The sealing ring 28 improves the sealing performance of the connection. The inner wall of the bushing 12 is higher at both ends and lower in the middle, thus forming a recessed groove 29 on the inner wall of the bushing 12, reducing the contact area between the bushing 12 and the rotating shaft 8, and facilitating assembly. A pressure ring 30 and a limiting ring 31 are installed at the end of the rotating shaft 8. The pressure ring 30 is pressed between the inner ring of the bearing 10 and the limiting ring 31, and the limiting ring 31 is fixedly connected to the rotating shaft 8. An elastic washer 21 is installed between the limiting ring 31 and the pressure ring 30. The pressure ring 30 and the limiting ring 31 provide axial positioning for the inner ring of the bearing 10.

[0035] The sealing lip 14 includes an annular body 32, an annular front lip 33, and an annular rear lip 34. The annular front lip 33 bends forward and fits tightly against the bushing 12, while the annular rear lip 34 bends backward and fits tightly against the bushing 12. A connecting hole 17 is provided at the bottom of the mounting groove 18 of the bearing housing 9. The annular body 32 is tightly installed in the connecting hole 17, and an annular rib 35 is provided on the inner wall of the connecting hole 17. The end of the annular body 32 rests against the annular rib 35 for axial positioning. The sealing performance of the sealing lip 14 is greatly improved by the annular front lip 33 and the annular rear lip 34.

[0036] A cooling channel 36 is provided inside the side cover 1. The cooling channel 36 is arranged circumferentially along the edge of the side cover 1. Coolant is introduced into the cooling channel 36 to cool the side cover 1, so that the frictional heat of the sealing and lubrication system is quickly removed, improving the operating conditions and thus increasing the service life of the sealing system, which can generally be extended by 10-12 months.

[0037] The labyrinth sealing ring 11, bushing 12, bearing washer 27, inner ring of bearing 10, pressure ring 30, and limiting ring 31 are all connected and fastened to the rotating shaft 8 and rotate together with the rotating shaft 8. Lubricating oil is filled in the oil cavity 3 to lubricate the rotating parts and also remove frictional heat, improving operating conditions and extending the service life of the sealing lip 14. The sealing lip 14 acts as a seal, blocking the flow of lubricating oil. The labyrinth sealing ring 11 and the sealing lip 14 together form a combined sealing structure, improving the sealing effect. The labyrinth sealing ring 11 and the side cover 1 form a non-contact labyrinth-shaped cavity through the cooperation of the labyrinth ring groove 15 and the labyrinth convex ring 16, blocking the path of harmful media, especially particulate pollutants, to enter along the axial direction of the rotating shaft 8. Harmful media diffuse radially, making it difficult for them to accumulate on the rotating shaft 8, preventing contact between harmful media and the sealing lip 14, effectively protecting the sealing lip 14 as the main seal, improving sealing performance, and extending the service life of the sealing lip 14. The bearing housing 9 facilitates the installation of the bearing 10 and the sealing lip 14. The bushing 12 positions the bearing 10. During the operation of the vacuum pump 7, coolant flows into the cooling channel 36 to cool the side cover 1, rapidly removing the frictional heat from the sealing and lubrication system, improving operating conditions, and thus extending the service life of the sealing system.

[0038] Example 2: A vacuum pump sealing structure (see...) Figure 3 A side cover 1 and a rear cover 2 are provided on one side of the vacuum pump 7, forming an oil chamber 3 between the side cover 1 and the rear cover 2. The vacuum pump 7 includes a pump housing 4, within which a pump chamber 5 is provided. An end cover 6 is connected to the front end of the pump housing 4, and the side cover 1 is connected to the rear end of the pump housing 4. The rear cover 2 is securely connected to the side cover 1. A rotating shaft 8 and a bearing seat 9 are installed on the side cover 1. A bearing 10 is installed between the bearing seat 9 and the rotating shaft 8. One end of the rotating shaft 8 is connected to the end cover 6, and the other end of the rotating shaft 8 is connected to the side cover 1.

[0039] A labyrinth seal ring 11 and a bushing 12 are installed on the rotating shaft 8. The bushing 12 rests between the labyrinth seal ring 11 and the inner ring of the bearing 10. A shoulder 13 is provided on the rotating shaft 8. One end of the labyrinth seal ring 11 rests on the shoulder 13, and the other end rests on the end of the bushing 12. A sealing lip 14 is installed between the bushing 12 and the bearing housing 9. The sealing lip 14 is made of polytetrafluoroethylene (PTFE), which is resistant to high temperatures and corrosion and has a long service life. Several labyrinth seal ring grooves 15 are provided on the side of the labyrinth seal ring 11, and several labyrinth convex rings 16 are provided on the side cover 1. The labyrinth convex rings 16 are inserted into the labyrinth seal ring grooves 15. The radial clearance between the labyrinth seal ring grooves 15 and the labyrinth convex rings 16 is 0.15-0.25 mm. The radial clearance is set within the range of 0.15-0.25 mm, which can block most of the dirt, especially crystalline particles, making it difficult for harmful media to come into contact with the sealing lip 14.

[0040] A mounting groove 18 is provided on the bearing housing 9, and a raised ring 19 is provided at the bottom of the mounting groove 18. The bearing 10 is fitted into the mounting groove 18, with the outer ring of the bearing 10 resting on the raised ring 19. A bearing cap 20 is fastened to the outer end of the bearing housing 9, and the bearing cap 20 presses against the outer ring of the bearing 10. An elastic washer 21 is installed between the bearing cap 20 and the outer ring of the bearing 10. The axial positioning of the outer ring of the bearing 10 is achieved through the setting of the raised ring 19 and the bearing cap 20, ensuring the stability and reliability of the bearing 10 installation.

[0041] Two shafts 8 are provided. Two grooves 22 corresponding to the shafts 8 are provided on the side cover 1. Mounting holes 23 are provided at the bottom of the grooves 22. The bearing seat 9 is fastened to the open end of the groove 22. The end of the bearing seat 9 is provided with a flange 24, which presses against the end face of the side cover 1 for positioning. A gap is provided between the bearing seat 9 and the bottom of the groove 22.

[0042] An extension ring 25 is provided on the labyrinth sealing ring 11. The extension ring 25 is installed between the inner wall of the mounting hole 23 and the outer wall of the rotating shaft 8, with the end of the extension ring 25 abutting against the shoulder 13 of the rotating shaft 8. The shoulder 13 of the rotating shaft 8 is close to the end face of the side cover 1. A labyrinth disk 26 extending radially outward is provided on the labyrinth sealing ring 11, and a labyrinth ring groove 15 is provided on the side of the labyrinth disk 26. A labyrinth convex ring 16 is provided on the bottom surface of the recess 22.

[0043] A bearing washer 27 is installed between the bushing 12 and the inner ring of the bearing 10, and a sealing ring 28 is installed between the bearing washer 27 and the bushing 12. The bearing washer 27 provides axial positioning for the bearing 10. The sealing ring 28 improves the sealing performance of the connection. The inner wall of the bushing 12 is higher at both ends and lower in the middle, thus forming a recessed groove 29 on the inner wall of the bushing 12, reducing the contact area between the bushing 12 and the rotating shaft 8, and facilitating assembly. A pressure ring 30 and a limiting ring 31 are installed at the end of the rotating shaft 8. The pressure ring 30 is pressed between the inner ring of the bearing 10 and the limiting ring 31, and the limiting ring 31 is fixedly connected to the rotating shaft 8. An elastic washer 21 is installed between the limiting ring 31 and the pressure ring 30. The pressure ring 30 and the limiting ring 31 provide axial positioning for the inner ring of the bearing 10.

[0044] The sealing lip 14 includes an annular body 32, an annular front lip 33, and an annular rear lip 34. The annular front lip 33 bends forward and fits tightly against the bushing 12, while the annular rear lip 34 bends backward and fits tightly against the bushing 12. A connecting hole 17 is provided at the bottom of the mounting groove 18 of the bearing housing 9. The annular body 32 is tightly installed in the connecting hole 17, and an annular rib 35 is provided on the inner wall of the connecting hole 17. The end of the annular body 32 rests against the annular rib 35 for axial positioning. The sealing performance of the sealing lip 14 is greatly improved by the annular front lip 33 and the annular rear lip 34.

[0045] A cooling channel 36 is provided inside the side cover 1. The cooling channel 36 is arranged circumferentially along the edge of the side cover 1. Coolant is introduced into the cooling channel 36 to cool the side cover 1, so that the frictional heat of the sealing and lubrication system is quickly removed, improving the operating conditions and thus increasing the service life of the sealing system, which can generally be extended by 10-12 months.

[0046] A radially outwardly extending baffle 37 is provided on the bushing 12, and several baffle protrusions 38 are provided on the baffle 37. Several baffle ring grooves 39 are provided on the bearing housing 9, and the baffle ring grooves 39 are located at the bottom of the mounting groove 18 of the bearing housing 9. The baffle protrusions 38 are inserted into the baffle ring grooves 39. The radial clearance between the baffle protrusions 38 and the baffle ring grooves 39 is 0.1-0.3mm. The baffle 37 provided on the bushing 12 blocks impurities in the oil on the other side of the sealing lip 14, preventing residual impurities in the oil from contacting the sealing lip 14.

[0047] The front and rear sides of the sealing lip 14 form a labyrinth-like cavity, which effectively prevents impurities from flowing to the sealing lip 14 and coming into contact with it. This helps to improve the sealing effect of the sealing lip 14 and extend its service life.

[0048] The labyrinth sealing ring 11, bushing 12, bearing washer 27, inner ring of bearing 10, pressure ring 30, and limiting ring 31 are all connected and fastened to the rotating shaft 8 and rotate together with the rotating shaft 8. Lubricating oil is filled in the oil cavity 3 to lubricate the rotating parts and also remove frictional heat, improving operating conditions and extending the service life of the sealing lip 14. The sealing lip 14 acts as a seal, blocking the flow of lubricating oil. The labyrinth sealing ring 11 and the sealing lip 14 together form a combined sealing structure, improving the sealing effect. The labyrinth sealing ring 11 and the side cover 1 form a non-contact labyrinth-shaped cavity through the cooperation of the labyrinth ring groove 15 and the labyrinth convex ring 16, blocking the path of harmful media, especially particulate pollutants, to enter along the axial direction of the rotating shaft 8. Harmful media diffuse radially, making it difficult for them to accumulate on the rotating shaft 8, preventing contact between harmful media and the sealing lip 14, effectively protecting the sealing lip 14 as the main seal, improving sealing performance, and extending the service life of the sealing lip 14. The bearing housing 9 facilitates the installation of the bearing 10 and the sealing lip 14. The bushing 12 positions the bearing 10. During the operation of the vacuum pump 7, coolant flows into the cooling channel 36 to cool the side cover 1, rapidly removing the frictional heat from the sealing and lubrication system, improving operating conditions, and thus extending the service life of the sealing system.

[0049] The embodiments described above are merely preferred solutions of this utility model and are not intended to limit this utility model in any way. Other variations and modifications are possible without departing from the technical solutions described in the claims.

Claims

1. A vacuum pump sealing structure, wherein a side cover and a rear cover are provided on one side of the vacuum pump, and an oil cavity is formed between the side cover and the rear cover, characterized in that, A rotating shaft and bearing housing are installed on the side cover. A bearing is installed between the bearing housing and the rotating shaft. A labyrinth seal ring and a bushing are installed on the rotating shaft. The bushing is positioned between the labyrinth seal ring and the inner ring of the bearing. A sealing lip is installed between the bushing and the bearing housing. Several labyrinth ring grooves are provided on the side of the labyrinth seal ring. Several labyrinth convex rings are provided on the side cover. The labyrinth convex rings are inserted into the labyrinth ring grooves.

2. The vacuum pump sealing structure according to claim 1, characterized in that, The bearing housing is provided with a mounting groove, and a raised ring is provided at the bottom of the mounting groove. The bearing is fitted into the mounting groove, and the outer ring of the bearing rests on the raised ring.

3. The vacuum pump sealing structure according to claim 1, characterized in that, A cooling channel is provided inside the side cover.

4. The vacuum pump sealing structure according to claim 1, characterized in that, The bearing housing is fastened to the outer end of the bearing cap, which presses against the outer ring of the bearing.

5. The vacuum pump sealing structure according to claim 1, characterized in that, The sealing lip includes an annular body, an annular front lip, and an annular rear lip. The annular front lip bends forward and fits tightly against the bushing, while the annular rear lip bends backward and fits tightly against the bushing.

6. The vacuum pump sealing structure according to claim 1, characterized in that, A bearing washer is installed between the bushing and the inner ring of the bearing.

7. A vacuum pump sealing structure according to claim 6, characterized in that, A sealing ring is installed between the bearing washer and the bushing.

8. The vacuum pump sealing structure according to claim 1, characterized in that, The radial clearance between the labyrinth annular groove and the labyrinth convex ring is 0.15-0.25 mm.

9. A vacuum pump sealing structure according to claim 1, characterized in that, A pressure ring and a limiting ring are installed at the end of the shaft. The pressure ring is pressed between the inner ring of the bearing and the limiting ring, and the limiting ring is fixedly connected to the shaft.

10. A vacuum pump sealing structure according to any one of claims 1 to 9, characterized in that, The bushing is provided with a radially outward extending barrier disc, and the barrier disc is provided with several rings of barrier protrusions. The bearing housing is provided with several rings of barrier ring grooves, and the barrier protrusions are inserted into the barrier ring grooves.

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