An engine intermediate fulcrum inner ring support structure

Abstract

The present application belongs to the field of intermediate casing design, and is an intermediate fulcrum inner ring supporting structure of an engine, comprising a high-turbo disk, a second sealing grate ring, a bearing inner ring and a retaining frame; the axial compression between the support ring and the support member is achieved by tightening bolts, the high-turbo rear shaft neck is eliminated, the radial positioning between the support member and the support ring is achieved by stopper matching and the radial matching tightness is ensured, and the axial compression and radial positioning of the second sealing grate ring are jointly provided by the support ring and the support member; by making the minimum distance from the bearing inner ring to the axis of the low-pressure rotor the same as the minimum distance from the high-turbo disk to the axis of the low-pressure rotor, the structure of the high-pressure rotor is no longer arranged on the inner side of the bearing inner ring, so that the bearing inner ring, the retaining frame and the bearing outer ring are all closer to the axis position of the low-pressure rotor, the radial space of the intermediate fulcrum inner ring supporting structure is compressed, the diameter of the bearing inner ring is reduced, and the rotation speed of the bearing roller is reduced, providing space for reducing the heat generated by the bearing.

Description

Technical Field

[0001] The present application belongs to the field of intermediate fulcrum design, and in particular relates to an engine intermediate fulcrum inner ring support structure. Background Art

[0002] The intermediate pivot is a type of pivot commonly used in current twin-rotor aviation turbofan engines, including pivot bearings, oil supply and return structures for cooling and lubricating bearings, and bearing cavity sealing structures. The advantage of the intermediate pivot over the load-bearing frame between turbine stages is its compact structure. However, since the intermediate pivot is supported between the high- and low-pressure rotors, the intermediate pivot bearing has high requirements for the reliability of the supporting structure to prevent the inner and outer rings of the bearing from deflecting and causing coupled vibrations of the high- and low-pressure rotors; since the intermediate pivot is located between the high- and low-pressure rotors, the space for the intermediate pivot-related bearings, oil supply and return structures, and sealing structures is limited. Therefore, the design of the intermediate pivot support structure is relatively difficult.

[0003] The intermediate fulcrum can be divided into the following types according to the supporting method of the inner and outer rings of the bearing: the inner ring is supported on the high-pressure rotor, and the outer ring is supported on the low-pressure rotor; the outer ring is supported on the high-pressure rotor, and the inner ring is supported on the low-pressure rotor. The two supporting methods each have their advantages and disadvantages.

[0004] Traditional intermediate support inner ring support structure Figure 1 As shown, rollers 5 and retainers 7 are provided on the outer side of the bearing inner ring 4, and the bearing inner ring 4 is supported on the high-vortex rear journal 2, which is connected to the high-vortex disk 1 through the first bolt 8 and the first nut 9. The clamping nut 7 realizes the axial clamping of the bearing inner ring 4. In order to ensure the sealing of the bearing cavity, the first sealing grate ring 3 is assembled on the high-vortex rear journal 2.

[0005] The traditional solution of the intermediate pivot inner ring support structure is that the inner ring of the bearing is sleeved on the high-turbulence rear journal, and the inner ring is effectively positioned through the radial fit tightness of the bearing inner ring and the high-turbulence rear journal and the axial clamping force of the clamping nut. Due to the different materials of the bearing inner ring and the high-turbulence rear journal, the axial and radial thermal expansion at the same temperature are different; at the same time, the ambient temperature around the pivot and the heat generated by the bearing change with the engine working conditions during operation, especially under complex working conditions such as rapid push-up and pull-down, the ambient temperature and bearing heat generation change more. The above factors lead to different axial and radial deformations of the bearing inner ring and the high-turbulence rear journal, and the radial fit and axial clamping state of the bearing inner ring and the high-turbulence rear journal change. The bearing inner ring and the high-turbulence rear journal may separate, resulting in loosening of the bearing inner ring, which in turn brings about problems such as vibration of the entire machine and bearing damage, affecting the safe operation of the engine.

[0006] Since the grate ring is assembled on the high-turbulence rear journal, it is also positioned by radial tightness and axial compression. After the grate ring is assembled, the radial tightness will cause the high-turbulence rear journal to deform, affecting the matching state of the bearing inner ring. At the same time, the grate ring is also axially compressed by a compression nut on the axial compression path of the bearing inner ring. The axial deformation of the grate ring in the working state will also affect the axial compression of the bearing inner ring.

[0007] The intermediate bearing rollers rotate at high speeds, and the bearings generate a lot of heat, which has a certain impact on the bearing life. Due to the size restrictions of the high-turbulence rear journal structure, the size of the intermediate bearing cannot be reduced to reduce the bearing roller rotation speed and bearing heat.

[0008] The radial height of the high-vortex rear journal and the high-vortex disk connection installation edge is relatively high, the high-vortex rear journal is relatively rigid, and the intermediate bearing bears a relatively high fulcrum dynamic load; the high-vortex rear journal is relatively rigid, which will also cause the deformation of the high-vortex disk to have a greater impact on the intermediate bearing.

[0009] Therefore, how to improve the positioning accuracy and installation stability of the bearing inner ring is a problem that needs to be solved. Summary of the invention

[0010] The purpose of this application is to provide an engine intermediate fulcrum inner ring support structure to solve the problem in the prior art that the inner ring of the bearing is easy to loosen and the axial compression is difficult to stabilize due to the different axial and radial deformations of the inner ring of the bearing and the high-turbo rear journal.

[0011] The technical solution of the present application is: an engine intermediate fulcrum inner ring support structure, comprising a high scroll, a second sealing grate ring, a bearing inner ring and a retaining frame, the retaining frame is coaxially arranged on the outside of the bearing inner ring, the bearing inner ring extends to one side of the high scroll with an integrally arranged annular support member, the high scroll is provided with a support ring corresponding to the support member, the second sealing grate ring is arranged between the support ring and the support member of the bearing inner ring, the support ring, the second sealing grate ring and the support member are connected by fastening bolts along the axial direction, the support member cooperates with the radial stop of the support ring, the high scroll is integrally connected with an annular support frame, the bearing inner ring and the annular support frame are arranged side by side.

[0012] Preferably, the annular support frame comprises a support arm (5) and a rotating sleeve; the rotating sleeve is coaxially arranged on the outside of the low-pressure rotor, the support arm (5) is obliquely connected between the high scroll and the rotating sleeve, and the support ring is integrally coaxially connected to the outer ring surface of the rotating sleeve.

[0013] Preferably, the support member includes a transverse connecting ring and a longitudinal connecting ring, the cross-sections of the transverse connecting ring and the longitudinal connecting ring are L-shaped, the longitudinal connecting ring is connected to the support ring and the second sealing comb ring by bolts, and the transverse connecting ring cooperates with the radial stop of the rotating sleeve.

[0014] Preferably, the distance from the inner ring surface of the transverse connecting ring to the axis of the low-pressure rotor is greater than the distance from the inner ring surface of the axial inner ring to the axis of the low-pressure rotor, a stop boss is provided on the outer ring surface of the rotating sleeve, and one end of the transverse connecting ring close to the longitudinal connecting ring cooperates with the radial stop of the stop boss, and the radial stop of the transverse connecting ring and the rotating sleeve is an interference fit.

[0015] Preferably, an axial gap is provided between the rotating sleeve and an end of the bearing inner ring close to the high scroll.

[0016] Preferably, the second sealing grate ring includes a connecting portion and a sealing portion; the connecting portion is arranged along the radial direction of the low-pressure rotor and the connecting portion is tightly fitted between the support ring and the support member, the sealing portion is arranged on the outer side of the connecting portion, and sealing grate teeth are provided on the sealing portion, and the inner side of the sealing portion cooperates with the radial stop on the outer side of the support ring.

[0017] Preferably, the sealing comb teeth include first comb teeth and second comb teeth, the first comb teeth are used to seal the bearing cavity, and the second comb teeth are used to form a sealing cavity.

[0018] Preferably, there is a gap between the second comb teeth and the annular support frame, and the nut of the fastening bolt is arranged at the gap position between the second comb teeth and the annular support frame.

[0019] Preferably, a first annular boss and a second annular boss are provided on the inner ring surface of the bearing inner ring, the first boss and the second boss are respectively provided at two ends of the bearing inner ring, and a lubricating oil containing cavity is formed between the first boss and the second boss.

[0020] Preferably, a hook groove is provided on the outer ring surface of the end of the bearing inner ring away from the high scroll.

[0021] The present application discloses an intermediate fulcrum inner ring support structure for an engine, comprising a high-turbo disk, a second sealing grate ring, a bearing inner ring and a retaining frame; the axial compression between the support ring and the support member is achieved by tightening bolts, the high-turbo rear shaft neck is eliminated, the radial positioning between the support member and the support ring is achieved by stopper matching and the radial matching tightness is ensured, and since the second sealing grate ring is arranged between the support ring and the support member, the axial compression and radial positioning of the second sealing grate ring are jointly provided by the support ring and the support member; the structure of the high-pressure rotor is no longer arranged on the inner side of the bearing inner ring, but the high-pressure rotor and the bearing inner ring are axially arranged side by side, so that the bearing inner ring, the retaining frame and the bearing outer ring are all closer to the axial position of the low-pressure rotor, the radial space of the intermediate fulcrum inner ring support structure is compressed, the diameter of the bearing inner ring is reduced, and the rotation speed of the bearing roller is reduced, providing space for reducing the heat generated by the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0023] Figure 1 It is a schematic diagram of the cross-sectional structure of the intermediate fulcrum of the background technology;

[0024] Figure 2 This is a schematic diagram of the overall structure of the intermediate fulcrum support of this application;

[0025] Figure 3 This is a schematic cross-sectional view of the inner ring support of the intermediate fulcrum bearing in this application.

[0026] 1. High-pressure turbine disc; 2. High-pressure turbine rear journal; 3. First sealing grate ring; 4. Bearing inner ring; 5. Roller; 6. Cage; 7. Pressing nut; 8. First bolt; 9. First nut; 10. Annular support frame; 11. Second sealing grate ring; 12. Support ring; 13. Fastening bolt; 14. Hook groove; 15. Support arm; 16. Rotating sleeve; 17. Horizontal connecting ring; 18. Longitudinal connecting ring; 19. Low-pressure rotor; 20. Connecting part; 21. Sealing part; 22. First grate teeth; 23. Second grate teeth; 24. First boss; 25. Second boss. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0028] An engine intermediate support inner ring support structure, such as Figure 2 , Figure 3 As shown, it includes a high-pressure scroll 1, a second sealing grate ring 11, a bearing inner ring 4 and a retainer 6. The high-pressure scroll 1 is a high-pressure rotor component, connected to the high-pressure turbine, and the bearing is arranged between the high-pressure rotor component and the low-pressure rotor 19. The bearing is preferably a cylindrical roller bearing, including a bearing outer ring, a retainer 6 and a bearing inner ring 4. The retainer 6 is coaxially arranged between the bearing outer ring and the bearing inner ring 4, and the low-pressure rotor 19 is arranged on the inner side of the high-pressure rotor component and the bearing inner ring 4, and the three are coaxially arranged; the second sealing grate ring 11 is used for sealing the bearing on the one hand, and for forming a sealing cavity on the other hand.

[0029] Preferably, an annular support frame 10 is integrally connected to the high scroll 1, and the annular support frame 10 includes a support arm 15 and a rotating sleeve 16; the rotating sleeve 16 is a cylindrical structure and the rotating sleeve 16 is coaxially arranged on the outside of the low-pressure rotor 19, the support arm 15 is obliquely connected between the high scroll 1 and the rotating sleeve 16, and the support ring 12 is integrally coaxially connected to the outer ring surface of the rotating sleeve 16.

[0030] Preferably, the bearing inner ring 4 has an integrally arranged annular support extending toward one side of the high scroll 1, and the high scroll 1 is provided with a support ring 12 arranged corresponding to the support member, and the second sealing grate ring 11 is arranged between the support ring 12 and the support member, and the support ring 12, the second sealing grate ring 11 and the support member are threadedly connected with a fastening bolt 13 along the axial direction, and a nut is connected to the end of the fastening bolt 13, and the support member cooperates with the radial stop of the support ring 12, and the bearing inner ring 4 and the annular support frame (10) are arranged side by side.

[0031] Preferably, the support member includes a transverse connecting ring 17 and a longitudinal connecting ring 18, and the cross-sections of the transverse connecting ring 17 and the longitudinal connecting ring 18 are L-shaped. The distance from the inner ring surface of the transverse connecting ring 17 to the axis of the low-pressure rotor 19 is greater than the distance from the inner ring surface of the axial inner ring to the axis of the low-pressure rotor 19, so that the radial position of the transverse connecting ring 17 is higher than the bearing inner ring 4, and the rotating sleeve 16 can be inserted between the transverse connecting ring 17 and the bearing inner ring 4 for support and position limiting. A stop boss is provided on the outer ring surface of the rotating sleeve 16, and one end of the transverse connecting ring 17 close to the longitudinal connecting ring 18 is matched with the radial stop of the stop boss, and the stop fit is a tight fit.

[0032] The bearing inner ring 4 and the high scroll 1 are accurately and reliably centered by the stopper of the rotating sleeve 16 and the transverse connecting ring 17. On the one hand, the stopper length is short, and the interference fit of the stopper has little effect on the deformation of the bearing inner ring 4 and the rotating sleeve 16, and the reduced deformation of the bearing inner ring can effectively improve the working environment of the bearing; on the other hand, the stopper height is reduced, which reduces the influence of different radial deformation amounts caused by different materials and temperatures of the bearing inner ring 4 and the annular support frame (10) on the stopper fit, thereby improving the reliability of the bearing centering.

[0033] The axial compression between the support ring 12 and the longitudinal connecting ring 18 is achieved by tightening the bolts 13. The end friction caused by the axial compression force can effectively prevent the relative movement of the bearing inner ring 4 and the rotating sleeve 16. At the same time, the bolts also achieve physical anti-rotation of the bearing inner ring 4 and the rotating sleeve 16, further improving the reliability of the bearing centering. This structure eliminates the high-vortex rear journal 2 and the clamping nut 7, and the structure is more compact.

[0034] The structure of the high-pressure rotor is no longer arranged on the inner side of the bearing inner ring 4, but the high-pressure rotor and the bearing inner ring 4 are axially arranged side by side, so that the bearing inner ring 4, the retaining frame 6 and the bearing outer ring are all closer to the axial position of the low-pressure rotor 19, the radial space of the intermediate fulcrum inner ring support structure is compressed, the diameter of the bearing inner ring 4 is reduced, and the rotation speed of the bearing roller 5 is reduced, providing space for reducing the heat generated by the bearing.

[0035] The support ring 12 integrally provided with the high scroll disk 1 is directly connected to the support member. The radial height of the support arm 15 is lower than that of the high scroll rear journal 2, and the radial rigidity is weakened. The fulcrum dynamic load and deformation influence brought by the high scroll disk 1 to the intermediate bearing are reduced, and the working environment of the intermediate bearing is greatly improved at this time.

[0036] Preferably, there is a gap between the rotating sleeve 16 and the end of the bearing inner ring 4 close to the high scroll 1. When the rotating sleeve 16 undergoes thermal expansion, the existence of the gap can prevent the rotating sleeve 16 and the bearing inner ring 4 from influencing each other.

[0037] Preferably, the second sealing comb ring 11 includes a connecting portion 20 and a sealing portion 21; the connecting portion 20 is arranged along the radial direction of the low-pressure rotor 19 and the connecting portion 20 is tightly fitted between the support ring 12 and the support member, the sealing portion 21 is arranged on the outer side of the connecting portion 20, and the sealing portion 21 is provided with sealing comb teeth. The connecting portion 20 and the sealing portion 21 are combined to form a T-shaped structure, one side of which is convenient for bolt fixing, and the other side can perform stable sealing.

[0038] Preferably, the sealing grate teeth include a first grate teeth 22 and a second grate teeth 23. The first grate teeth 22 are used for sealing with the bearing, and the second grate teeth 23 are used for sealing the high scroll 1. The radial position of the second grate teeth 23 is higher than that of the first grate teeth 22. Since the first grate teeth 22 and the second grate teeth 23 are integrally arranged, the first grate teeth 22 and the second grate teeth 23 can be positioned relative to each other, and the position will not change, so as to ensure the stability of the seal.

[0039] Since the second sealing grate ring 11 is precisely positioned by the support ring 12 and the sealing grate teeth on the high-turbulence rear journal 2 are removed, the second sealing grate ring 11 is now used as a separate component to form a sealing cavity and provide sealing protection for the bearing cavity. While ensuring installation accuracy, disassembly and adjustment are more convenient. Compared with setting two groups of sealing grate teeth in different positions, it is more reasonable to design the spatial layout by using the second sealing grate ring 11 as a separate component, which provides space for the installation and tightening of the nuts of the fastening bolts 13.

[0040] Preferably, there is a sufficient interval between the second comb teeth 23 and the annular support frame 10, and the nut of the fastening bolt (13) is arranged at the interval position between the second comb teeth 23 and the annular support frame 10. The interval setting can ensure the installation and tightening of the connecting nut.

[0041] Preferably, an annular first boss 24 and a second boss 25 are provided on the inner ring surface of the bearing inner ring 4, and the first boss 24 and the second boss 25 are respectively provided at both ends of the bearing inner ring 4, and a lubricating oil receiving cavity is formed between the first boss 24 and the second boss 25. The lubricating oil receiving cavity makes use of the axial space as much as possible without increasing the depth and thus affecting the rigidity of the bearing inner ring 4, so as to achieve the largest lubricating oil receiving cavity. After the lubricating oil reaches the bearing inner ring 4, it can be temporarily stored in the lubricating oil receiving cavity between the first boss 24 and the second boss 25 to ensure the lubricating oil collection efficiency and meet the bearing lubrication and cooling requirements.

[0042] Preferably, a U-shaped hook groove 14 is provided on the outer ring surface of the end of the bearing inner ring away from the high scroll plate, which is used for applying force to the disassembly tooling installation of the bearing inner ring.

[0043] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. An engine intermediate fulcrum inner ring support structure, comprising a high scroll (1), a second sealing grate ring (11), a bearing inner ring (4) and a retainer (6), wherein the retainer (6) is coaxially arranged on the outer side of the bearing inner ring (4), Features: The bearing inner ring (4) is provided with an integrally arranged annular support member extending toward one side of the high scroll (1); the high scroll (1) is provided with a support ring (12) arranged corresponding to the support member; the second sealing grate ring (11) is arranged between the support ring (12) and the support member of the bearing inner ring (4); the support ring (12), the second sealing grate ring (11) and the support member are connected by fastening bolts (13) along the axial direction; the support member and the support ring (12) are matched with radial stoppers; the high scroll (1) is integrally connected with an annular support frame (10); the bearing inner ring (4) and the annular support frame (10) are arranged side by side; The annular support frame (10) comprises a support arm (15) and a rotating sleeve (16); the rotating sleeve (16) is coaxially arranged on the outside of the low-pressure rotor (19), the support arm (15) is obliquely connected between the high scroll (1) and the rotating sleeve (16), and the support ring (12) is coaxially connected to the outer ring surface of the rotating sleeve (16) in an integral manner.

2. The engine intermediate fulcrum inner ring support structure according to claim 1, Features: The support member comprises a transverse connecting ring (17) and a longitudinal connecting ring (18); the cross sections of the transverse connecting ring (17) and the longitudinal connecting ring (18) are L-shaped; the longitudinal connecting ring (18) is connected to the support ring (12) and the second sealing comb tooth ring (11) by bolts; and the transverse connecting ring (17) cooperates with the radial stop of the rotating sleeve (16).

3. The engine intermediate support inner ring support structure as claimed in claim 2, Features: The distance between the inner ring surface of the transverse connecting ring (17) and the axis of the low-pressure rotor (19) is greater than the distance between the inner ring surface of the axial inner ring and the axis of the low-pressure rotor (19). A stop boss is provided on the outer ring surface of the rotating sleeve (16). One end of the transverse connecting ring (17) close to the longitudinal connecting ring (18) cooperates with the radial stop of the stop boss. The radial stop of the transverse connecting ring (17) and the rotating sleeve (16) is an interference fit.

4. The engine intermediate support inner ring support structure according to claim 1, Features: An axial gap is formed between the rotating sleeve (16) and the end of the bearing inner ring (4) close to the high scroll (1).

5. The engine intermediate fulcrum inner ring support structure according to claim 1, Features: The second sealing grate ring (11) comprises a connecting portion (20) and a sealing portion (21); the connecting portion (20) is arranged along the radial direction of the low-pressure rotor (19) and the connecting portion (20) is tightly fitted between the support ring (12) and the support member, the sealing portion (21) is arranged on the outer side of the connecting portion (20), and the sealing grate is provided on the sealing portion (21), and the inner side of the sealing portion (21) cooperates with the radial stopper on the outer side of the support ring (12).

6. The engine intermediate support inner ring support structure as claimed in claim 5, Features: The sealing comb teeth include first comb teeth (22) and second comb teeth (23), wherein the first comb teeth (22) are used to seal the bearing cavity, and the second comb teeth (23) are used to form a sealing cavity.

7. The engine intermediate support inner ring support structure according to claim 6, Features: There is a gap between the second comb teeth (23) and the annular support frame (10), and the nut of the fastening bolt (13) is arranged at the gap position between the second comb teeth (23) and the annular support frame (10).

8. The engine intermediate support inner ring support structure according to claim 1, Features: An annular first boss (24) and a second boss (25) are provided on the inner ring surface of the bearing inner ring (4); the first boss (24) and the second boss (25) are respectively provided at two ends of the bearing inner ring (4); and a lubricating oil receiving cavity is formed between the first boss (24) and the second boss (25).

9. The engine intermediate support inner ring support structure according to claim 1, Features: The outer ring surface of the bearing inner ring (4) at one end away from the high scroll (1) is provided with a hook groove (14).

Images