Oil leakage prevention structure of bearing cavity

Abstract

The invention relates to the technical field of aero-engines or gas turbines, and discloses a bearing cavity oil leakage prevention structure which is installed on a bearing. The bearing is mounted on the rotating shaft; the bearing comprises an inner ring and an outer ring which are sleeved at an interval; according to the bearing cavity oil leakage prevention structure, a first runway is arranged on the front portion of a bearing; the second runway is arranged behind the bearing; the two squirrel-cage type elastic supports are respectively arranged at the front end and the rear end of the outer ring along the axial direction; a bearing cavity surrounds the outer part of the squirrel-cage type elastic support; according to the bearing cavity oil leakage prevention structure, when the rotating shaft drives the inner ring to rotate, oil thrown out of the inner ring passes through the first runway and the second runway and is thrown to the circumferential wall face of the bearing cavity through the squirrel-cage type elastic support. The oil throwing-out direction is changed, oil is thrown to the circumferential wall face of the bearing cavity through the first runway, the second runway and the squirrel-cage type elastic support, the oil thrown out of the front side wall face and the rear side wall face in the bearing cavity is reduced, the oil is prevented from being excessively gathered on the front side wall face and the rear side wall face of the bearing cavity, and then leakage of the oil in the bearing cavity is prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengines or gas turbines, and particularly relates to an oil leakage prevention structure for a bearing cavity. Background Art

[0002] In an aeroengine or a gas turbine, a rotor and a stator are generally connected by a bearing. During normal operation of the bearing, heat dissipation and lubrication are required through a fluid. To ensure the stable and reliable operation of the aeroengine or the gas turbine, oil leakage from the bearing cavity should be avoided. The oil in the bearing cavity generally flows into the bearing cavity through a nozzle or an under-ring oil supply passage; after heat exchange and temperature rise of the oil, it is thrown out by the bearing, and part of the oil forms an oil film on the inner wall surface of the bearing cavity. In the existing structural design, a sealing structure is provided between the rotor and the stator, and the effectiveness of the sealing is ensured by adjusting the sealing clearance, the pressure difference inside and outside the bearing cavity, and the oil return flow capacity; by controlling the pressure difference on both sides of the sealing structure, most of the oil flows into the oil return passage, and the remaining small part of the oil is discharged from the bearing cavity through the ventilation passage, thus avoiding oil leakage from the bearing cavity. The sealing gas pressure in the existing design is selected according to the oil and gas pressure in the bearing cavity. However, due to the unreasonable design of the existing bearing cavity structure, the oil is thrown out in the form of droplets through the bearing, and accumulates to form lubricating oil blocks and liquid films on the front and rear side walls in the bearing cavity; when there are too many lubricating oil blocks and liquid films on the front and rear side walls in the bearing cavity, the oil is easily flowed along the wall surface of the bearing cavity to gather at the sealing runway; since the sealing runway is located at the rotor, the oil is thrown out of the bearing cavity through the runway gap, resulting in oil leakage. Summary of the Invention

[0003] In view of this, the present invention provides an oil leakage prevention structure for a bearing cavity to solve the problem that in the existing bearing cavity structure, the design is unreasonable, the oil is thrown out in the form of droplets through the bearing, and accumulates to form lubricating oil blocks and liquid films on the front and rear side walls in the bearing cavity; when there are too many lubricating oil blocks and liquid films on the front and rear side walls in the bearing cavity, the oil is easily flowed along the wall surface of the bearing cavity to gather at the sealing runway; since the sealing runway is located at the rotor, the oil is thrown out of the bearing cavity through the runway gap, resulting in oil leakage.

[0004] The present invention provides an oil leakage prevention structure for a bearing cavity, which is suitable for being installed on a bearing, and the bearing is suitable for being installed on a rotating shaft; the bearing includes: an inner ring and an outer ring which are sleeved at intervals, and rolling elements are arranged in contact between the inner ring and the outer ring; the oil leakage prevention structure for the bearing cavity includes:

[0005] A first runway, which is arranged at the front part of the bearing along the axial direction;

[0006] A second runway, which is arranged at the rear part of the bearing along the axial direction;

[0007] Two squirrel-cage elastic supports are respectively arranged at the front end and the rear end of the outer ring along the axial direction; a bearing cavity is circumferentially arranged outside the squirrel-cage elastic support;

[0008] The oil leakage prevention structure of the bearing cavity is adapted such that when the inner ring is driven to rotate by the rotating shaft, the oil liquid thrown out by the inner ring passes through the first runway and the second runway, and is thrown to the circumferential wall surface of the bearing cavity through the squirrel-cage elastic support. Beneficial effects: By adopting the above technical solutions, the present application changes the direction of the thrown oil liquid, and throws the oil liquid to the circumferential wall surface of the bearing cavity through the first runway, the second runway and the squirrel-cage elastic support, reducing the oil liquid thrown out on the front and rear side walls of the bearing cavity, preventing the excessive accumulation of the oil liquid on the front and rear side walls of the bearing cavity, and further preventing the leakage of the oil liquid in the bearing cavity. Moreover, the squirrel-cage elastic support is integrated in a limited space, and by adjusting the runout quantity and size of the squirrel-cage elastic support, the function of adjusting the fulcrum stiffness is realized, and at the same time, the weight of the oil leakage prevention structure of the bearing cavity is reduced.

[0009] Optionally, the outer diameter of the outer circumference of the first runway is larger than the inner diameter of the outer ring; the outer diameter of the outer circumference of the second runway is larger than the inner diameter of the outer ring. Beneficial effects: By adopting the above technical solutions, the present application enables the thrown oil liquid to be thrown to the circumferential wall surface of the bearing cavity through the squirrel-cage elastic support, further ensuring the effect of preventing oil leakage.

[0010] Optionally, one end of the first runway is in contact seal with the end face of the inner ring; a first annular groove is arranged on the outer circumference of the first runway; a first chamfer is arranged at the end of the outer circumference of the first runway close to the first annular groove; the first chamfer inclines from the outer peripheral side end far from the bearing to the inner peripheral side end close to the bearing;

[0011] One end of the second runway is in contact seal with the end face of the inner ring; a second annular groove is arranged on the outer circumference of the second runway; a second chamfer is arranged at the end of the outer circumference of the second runway close to the second annular groove; the second chamfer inclines from the outer peripheral side end far from the bearing to the inner peripheral side end close to the bearing. Beneficial effects: By adopting the above technical solutions, the present application throws the thrown oil liquid from the squirrel-cage elastic support to the circumferential wall surface of the bearing cavity through the arranged first chamfer and second chamfer, preventing oil leakage.

[0012] Optionally, the outer peripheral side end of the first chamfer does not exceed the range covered by the squirrel-cage elastic support along the axial direction; the outer peripheral side end of the second chamfer does not exceed the range covered by the squirrel-cage elastic support along the axial direction. Beneficial effects: By adopting the above technical solutions, the present application enables the thrown oil liquid to be thrown to the circumferential wall surface of the bearing cavity through the squirrel-cage elastic support, further ensuring the effect of preventing oil leakage.

[0013] Optionally, it further includes:

[0014] The first sealing assembly is connected to the front squirrel-cage spring support to seal the front bearing cavity;

[0015] The second sealing assembly is connected to the rear squirrel-cage spring support to seal the rear bearing cavity.

[0016] Optionally, the first sealing assembly includes:

[0017] The first sealing housing is connected to the front squirrel-cage spring support at the rear end; a third annular groove is provided on the annular surface of the first sealing housing that contacts the circumferential wall surface of the front bearing cavity, and a sealing ring is provided in the third annular groove;

[0018] The second sealing assembly includes:

[0019] The second sealing housing is connected to the rear squirrel-cage spring support at the front end; the annular surface provided on the second sealing housing fits and seals with the circumferential wall surface of the rear bearing cavity. Beneficial effects: With the above technical solutions in this application, the sealing effects before and after the bearing cavity are ensured, and oil leakage is prevented.

[0020] Optionally, the first sealing assembly further includes:

[0021] The first graphite piece is arranged in the gap between the first sealing housing and the first raceway, and the inner side of the first graphite piece abuts against the annular flange of the first sealing housing; a first retaining ring is provided on the first sealing housing, and the first retaining ring fits and is arranged on the outer side of the first graphite piece;

[0022] The second sealing assembly further includes:

[0023] The second graphite piece is arranged in the gap between the second sealing housing and the second raceway, and the inner side of the second graphite piece abuts against the annular flange of the second sealing housing; a second retaining ring is provided on the second sealing housing, and the second retaining ring fits and is arranged on the outer side of the second graphite piece.

[0024] Optionally, a concave arc surface that transitions to the squirrel-cage spring support is provided on the inner side opposite to the annular flange of the first sealing housing. Beneficial effects: With the above technical solutions in this application, the flow of the oil fluid is adjusted through the concave arc surface, so that the oil fluid thrown to the front of the bearing cavity flows back into the first raceway along the concave arc surface through the squirrel-cage spring support, thereby preventing oil leakage.

[0025] Optionally, an extension ring extending in the entire width direction of the outer ring is provided between the squirrel-cage spring support at the rear and the outer ring. Beneficial effects: With the above technical solutions in this application, the flow trajectory of the oil fluid is adjusted through the extension ring to block the leakage of the oil fluid.

[0026] Optionally, both the first runway and the second runway are graphite runways. Description of the Drawings

[0027] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0028] Figure 1 It is a schematic semi-sectional structure diagram of the anti-oil leakage structure of the bearing cavity provided in the embodiment of the present invention;

[0029] Figure 2 It is a schematic partial sectional structure diagram of the anti-oil leakage structure of the bearing cavity provided in the embodiment of the present invention Figure 1 ;

[0030] Figure 3 It is a schematic partial sectional structure diagram of the anti-oil leakage structure of the bearing cavity provided in the embodiment of the present invention Figure 2 ;

[0031] Figure 4 It is a schematic sectional structure diagram of the first sealing housing provided in the embodiment of the present invention;

[0032] Figure 5 It is a schematic sectional structure diagram of the second sealing housing provided in the embodiment of the present invention.

[0033] Description of the Reference Numerals:

[0034] 1. First sealing housing; 2. Bearing cavity; 3. Squirrel cage spring support; 4. Outer ring; 5. First annular groove; 6. Second annular groove; 7. Sealing ring; 8. Circumferential wall surface; 9. Second sealing housing; 10. Extension ring; 11. First chamfer; 12. Second chamfer; 13. First retaining ring; 14. First graphite part; 15. First runway; 16. Cage; 17. Rolling element; 18. Inner ring; 19. Second runway; 20. Second graphite part; 21. Second retaining ring; 22. Third annular groove; 23. Concave arc surface. Detailed Embodiments

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0036] As Figures 1 to 5 shown, a specific implementation of the oil leakage prevention structure of the bearing cavity, the oil leakage prevention structure of the bearing cavity is adapted to be installed on a bearing, and the bearing is adapted to be installed on a rotating shaft; the bearing includes: an inner ring 18 and an outer ring 4 arranged at intervals, and rolling elements 17 are in contact between the inner ring 18 and the outer ring 4; the rolling range of the rolling elements 17 is restricted by a cage 16 between the inner ring 18 and the outer ring 4. The oil leakage prevention structure of the bearing cavity includes: a first raceway 15, a second raceway 19 and two cage-type elastic supports 3. Specifically, both the first raceway 15 and the second raceway 19 are graphite raceways. The cage-type elastic support is formed by a series of cylindrical ribs installed or welded at both end flange surfaces by threads, or by circumferentially grooving a hollow cylinder.

[0037] As Figure 1 shown, the first raceway 15 is arranged at the front part of the bearing along the axial direction. The second raceway 19 is arranged at the rear part of the bearing along the axial direction. The two cage-type elastic supports 3 are respectively arranged at the front end and the rear end of the outer ring 4 along the axial direction; a bearing cavity 2 is circumferentially arranged outside the cage-type elastic support 3. The oil leakage prevention structure of the bearing cavity is adapted to, when the rotating shaft drives the inner ring 18 to rotate, the oil discharged by the inner ring 18 passes through the first raceway 15 and the second raceway 19, and is thrown to the circumferential wall surface 8 of the bearing cavity 2 through the cage-type elastic support 3. The oil on the circumferential wall surface 8 flows into the oil return channel located at the bottom.

[0038] Further, as Figure 1 shown, the outer diameter of the outer circumference of the first raceway 15 is larger than the inner diameter of the inner wall of the outer ring 4; the outer diameter of the outer circumference of the second raceway 19 is larger than the inner diameter of the inner wall of the outer ring 4.

[0039] Further, as Figure 1 、 Figure 4 and Figure 5 shown, one end of the first raceway 15 is in contact and sealed with the end face of the inner ring 18; a first annular groove 5 is arranged on the outer circumference of the first raceway 15; a first chamfer 11 is arranged at the end of the outer circumference of the first raceway 15 close to the first annular groove 5; the first chamfer 11 slopes from the outer peripheral side end far from the bearing to the inner peripheral side end close to the bearing. One end of the second raceway 19 is in contact and sealed with the end face of the inner ring 18; a second annular groove 6 is arranged on the outer circumference of the second raceway 19; a second chamfer 12 is arranged at the end of the outer circumference of the second raceway 19 close to the second annular groove 6; the second chamfer 12 slopes from the outer peripheral side end far from the bearing to the inner peripheral side end close to the bearing. Further, the outer peripheral side end of the first chamfer 11 does not exceed the axially covered range of the cage-type elastic support 3; the outer peripheral side end of the second chamfer 12 does not exceed the axially covered range of the cage-type elastic support 3.

[0040] The oil leakage prevention structure of the bearing cavity described in this application further includes: a first sealing component and a second sealing component. The first sealing component is connected to the front squirrel cage spring support 3 to seal the front bearing cavity 2; the second sealing component is connected to the rear squirrel cage spring support 3 to seal the rear bearing cavity 2.

[0041] Specifically, as Figure 1 and Figure 2 shown, the first sealing component includes: a first sealing housing 1, the rear end of the first sealing housing 1 is connected to the front squirrel cage spring support 3; a third annular groove 22 is provided on the circumferential wall surface of the first sealing housing 1 in contact with the front bearing cavity 2, and a sealing ring 7 is provided in the third annular groove 22. The sealing ring 7 is a sealing rubber ring, and the sealing rubber ring is an O-ring.

[0042] Specifically, as Figure 1 and Figure 3 shown, the second sealing component includes: a second sealing housing 9, the front end of the second sealing housing 9 is connected to the rear squirrel cage spring support 3; the circumferential wall surface of the second sealing housing 9 is attached and sealed to the circumferential wall surface of the rear bearing cavity 2.

[0043] As Figure 1 shown, the first sealing component of this application further includes: a first graphite member 14, the first graphite member 14 is arranged in the gap between the first sealing housing 1 and the first raceway 15, and the inner side of the first graphite member 14 abuts against the annular flange of the first sealing housing 1; a first retaining ring 13 is provided on the first sealing housing 1, and the first retaining ring 13 is attached to the outer side of the first graphite member 14.

[0044] As Figure 1 shown, the second sealing component of this application further includes: a second graphite member 20, the second graphite member 20 is arranged in the gap between the second sealing housing 9 and the second raceway 19, and the inner side of the second graphite member 20 abuts against the annular flange of the second sealing housing 9; a second retaining ring 21 is provided on the second sealing housing 9, and the second retaining ring 21 is attached to the outer side of the second graphite member 20.

[0045] Furthermore, as Figure 1 and Figure 2 shown, a concave arc surface 23 leading to the squirrel cage spring support 3 is provided on the inner side opposite to the annular flange of the first sealing housing 1.

[0046] Furthermore, as Figure 1 and Figure 3 ​As shown, an extension ring 10 extending in the entire width direction of the outer ring 4 is provided between the squirrel-cage spring support 3 located at the rear and the outer ring 4.

[0047] The oil leakage prevention structure of the bearing cavity in this application has been numerically simulated, and the vortices induced in the bearing cavity can be adjusted, thereby changing the flow direction; and through the verification of actual experiments, the oil leakage prevention structure of the bearing cavity in this application has well solved the problem of oil leakage in the existing bearing cavity.

[0048] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. An oil leakage prevention structure for a bearing cavity, which is suitable for being installed on a bearing, and the bearing is suitable for being installed on a rotating shaft; the bearing includes: An inner ring (18) and an outer ring (4) are sleeved at intervals, and rolling elements (17) are arranged in contact between the inner ring (18) and the outer ring (4); the bearing cavity anti-oil leakage structure is characterized in that it includes: A first raceway (15), arranged at the front part of the bearing along the axial direction; A second raceway (19), arranged at the rear part of the bearing along the axial direction; Two squirrel-cage elastic supports (3), respectively arranged at the front end and the rear end of the outer ring (4) along the axial direction; a bearing cavity (2) is circumferentially arranged outside the squirrel-cage elastic support (3); The bearing cavity anti-oil leakage structure is adapted to enable the oil liquid thrown out by the inner ring (18) to pass through the first raceway (15) and the second raceway (19) and be thrown onto the circumferential wall surface (8) of the bearing cavity (2) via the squirrel-cage elastic support (3) when the rotating shaft drives the inner ring (18) to rotate.

2. The oil leakage prevention structure of the bearing cavity according to claim 1, wherein The outer diameter of the outer circumference of the first raceway (15) is larger than the inner diameter of the inner wall of the outer ring (4); the outer diameter of the outer circumference of the second raceway (19) is larger than the inner diameter of the inner wall of the outer ring (4).

3. The bearing cavity anti-oil leakage structure according to claim 1, characterized in that One end of the first raceway (15) is in contact sealing with the end face of the inner ring (18); a first annular groove (5) is arranged on the outer circumference of the first raceway (15); a first chamfer (11) is arranged at the end of the outer circumference of the first raceway (15) close to the first annular groove (5); the first chamfer (11) is inclined from the outer circumferential side end far from the bearing to the inner circumferential side end close to the bearing; One end of the second raceway (19) is in contact sealing with the end face of the inner ring (18); a second annular groove (6) is arranged on the outer circumference of the second raceway (19); a second chamfer (12) is arranged at the end of the outer circumference of the second raceway (19) close to the second annular groove (6); the second chamfer (12) is inclined from the outer circumferential side end far from the bearing to the inner circumferential side end close to the bearing.

4. The oil leakage prevention structure of the bearing cavity according to claim 3, wherein, The outer circumferential side end of the first chamfer (11) does not exceed the range covered by the squirrel-cage elastic support (3) along the axial direction; the outer circumferential side end of the second chamfer (12) does not exceed the range covered by the squirrel-cage elastic support (3) along the axial direction.

5. The oil leakage prevention structure for a bearing cavity according to any one of claims 1-4, characterized in that, It further includes: A first sealing assembly, connected to the squirrel-cage elastic support (3) at the front part to seal the bearing cavity (2) at the front part; A second sealing assembly, connected to the squirrel-cage elastic support (3) at the rear part to seal the bearing cavity (2) at the rear part.

6. The oil leakage prevention structure for the bearing cavity according to claim 5, wherein, The first sealing assembly includes: A first sealing housing (1), the rear end of which is connected to the squirrel-cage elastic support (3) at the front part; a third annular groove (22) is arranged on the circumferential surface of the first sealing housing (1) in contact with the circumferential wall surface of the bearing cavity (2) at the front part, and a sealing ring (7) is arranged in the third annular groove (22); The second sealing assembly includes: A second sealing housing (9), the front end of which is connected to the squirrel-cage elastic support (3) at the rear part; the circumferential surface of the second sealing housing (9) is in sealing fit with the circumferential wall surface of the bearing cavity (2) at the rear part.

7. The oil leakage prevention structure for the bearing cavity according to claim 6, characterized in that, The first sealing assembly further includes: The first graphite part (14) is arranged in the gap between the first sealing housing (1) and the first raceway (15), and the inner side of the first graphite part (14) abuts against the annular flange of the first sealing housing (1); a first retaining ring (13) is provided on the first sealing housing (1), and the first retaining ring (13) is arranged in contact with the outer side of the first graphite part (14). The second sealing assembly further includes: The second graphite part (20) is arranged in the gap between the second sealing housing (9) and the second raceway (19), and the inner side of the second graphite part (20) abuts against the annular flange of the second sealing housing (9); a second retaining ring (21) is provided on the second sealing housing (9), and the second retaining ring (21) is arranged in contact with the outer side of the second graphite part (20).

8. The oil leakage prevention structure of the bearing cavity according to claim 7, characterized in that, An arcuate concave surface (23) leading to the squirrel-cage spring support (3) is provided on the inner side opposite to the annular flange of the first sealing housing (1).

9. The oil leakage prevention structure of the bearing cavity according to any one of claims 1-4, characterized in that, An extension ring (10) extending in the entire width direction of the outer ring (4) is provided between the squirrel-cage spring support (3) at the rear and the outer ring (4).

10. The oil leakage prevention structure for the bearing cavity according to any one of claims 1-4, characterized in that, Both the first raceway (15) and the second raceway (19) are graphite raceways.

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