Bearing cavity sealing structure and aero-engine

Abstract

This application discloses a bearing cavity sealing structure and an aero-engine, belonging to the field of aero-engine bearing cavity sealing. The bearing cavity sealing structure includes a rotor and a stator. A journal is formed on the rotor, and a bearing housing is provided on the stator. A bearing cavity is formed between the bearing housing and the journal, and a bearing is installed in the bearing cavity. A sealing ring is provided on the stator, and a grating tooth that cooperates with the sealing ring is provided on the rotor. Air holes are opened on the grating tooth, and a gas flow channel is formed between the sealing ring and the grating tooth. The gas flow channel includes a bearing sealing flow channel from the air hole to the side closer to the bearing cavity and a return flow channel from the air hole to the side away from the bearing cavity. A first air guiding unit is provided at the end of the sealing ring near the bearing cavity. The first air guiding unit includes a support part connected to the sealing ring and an air guiding part connected to the support part. A guide hole perpendicular to the rotor axis is opened on the support part. The guide hole communicates with the bearing cavity, and one end of the air guiding part extends into the bearing sealing flow channel to guide the airflow in the bearing sealing flow channel into the guide hole. This application effectively solves the technical problem of balancing the size of the sealing gap and the lubrication effect of the bearing cavity.

Description

Technical Field

[0001] This invention relates to the field of bearing cavity sealing for aero-engines, and more particularly to a bearing cavity sealing structure and an aero-engine. Background Technology

[0002] The bearing housing is a critical component of an aero-engine, its main structure including the bearing housing, bearing, sealing elements, and lubrication system. The bearing housing provides robust support, ensuring precise alignment and stability of the bearing during high-speed rotation. The bearing itself is designed to withstand and reduce friction between the shaft and the housing, supporting the rotating components of the engine and enabling efficient and smooth operation. Sealing elements, such as O-rings and lip seals, prevent lubricant leakage and block external contaminants from entering. The lubrication system provides the necessary lubrication and cooling for the bearing, ensuring its normal operation under high-temperature, high-speed, and high-load conditions. Overall, the design of the bearing housing is crucial to ensuring the reliability, efficiency, and lifespan of the aero-engine.

[0003] When an aircraft engine is operating, the lubrication system lubricates and cools bearings, gears, and other components. However, oil vapor fills the bearing cavity. To prevent this oil vapor from overflowing into the flow channels and increasing oil consumption, the bearing cavity is typically sealed during component design. Common sealing structures include grate seals and graphite seals. However, sealing vapors can directly blow onto the bearing. If the grate seal clearance in the engine bearing cavity is too large, it can cause instability in the bearing cage and accelerate the loss of oil mist from the bearing cavity. Conversely, if the grate seal clearance is too small, it may cause the grate teeth to scrape during engine operation, affecting the normal operation of the rotor. Therefore, it is difficult to balance the seal clearance size with the lubrication effect of the bearing cavity. Summary of the Invention

[0004] This invention provides a bearing cavity sealing structure and an aero-engine to solve the technical problem of balancing the sealing gap size and the lubrication effect of the bearing cavity.

[0005] According to one aspect of the present invention, a bearing cavity sealing structure is provided, comprising a rotor and a stator. A journal is formed on the rotor, and a bearing housing is provided on the stator. A bearing cavity is formed between the bearing housing and the journal, and a bearing is installed within the bearing cavity. A sealing ring is provided on the stator, and grating teeth that cooperate with the sealing ring are provided on the rotor. Air holes are formed on the grating teeth, and a gas flow channel is formed between the sealing ring and the grating teeth. The gas flow channel includes a bearing sealing flow channel from the air holes towards the side near the bearing cavity and a return flow channel from the air holes away from the bearing cavity. A first air guiding unit is provided at one end of the sealing ring near the bearing cavity. The first air guiding unit includes a support portion connected to the sealing ring and an air guiding portion connected to the support portion. A guide hole perpendicular to the rotor axis is formed on the support portion, and the guide hole communicates with the bearing cavity. One end of the air guiding portion extends into the bearing sealing flow channel to guide the airflow within the bearing sealing flow channel into the guide hole.

[0006] Optionally, multiple first air guiding units are provided along the axial direction of the rotor, and air guiding cavities are formed between the air guiding parts of adjacent first guiding units, with the guide holes communicating with the air guiding cavities.

[0007] Optionally, the grating teeth are provided with air guiding protrusions that extend into the air guiding cavity, and a guiding channel is formed between the guiding protrusions and the first air guiding unit.

[0008] Optionally, the position of the top of the guide protrusion is adapted to the position of the guide hole.

[0009] Optionally, the bearing includes an outer ring, rolling elements, and an inner ring. The outer ring is connected to the bearing housing, and the inner ring is connected to the rotor. A second air guide unit is provided on the side of the inner ring near the grate teeth. The second air guide unit is located between the bearing sealing flow channel outlet and the rolling elements.

[0010] Optionally, the sealing ring has a cavity that communicates with the gas flow channel, and the opening of the cavity is opposite to the position of the vent.

[0011] Optionally, the comb teeth include a first tooth portion, a second tooth portion, and a connecting portion connecting the first tooth portion and the second tooth portion. The inner diameter of the first tooth portion is smaller than the inner diameter of the second tooth portion. The air hole is located on the connecting portion. The sealing ring includes a first sealing portion that mates with the first tooth portion and a second sealing portion that mates with the second tooth portion. The bearing sealing flow channel is located between the first tooth portion and the first sealing portion. The return flow channel is located between the second tooth portion and the second sealing portion.

[0012] Optionally, the comb teeth include a first tooth portion, a second tooth portion, and a connecting portion connecting the first tooth portion and the second tooth portion. The inner diameter of the first tooth portion is smaller than the inner diameter of the second tooth portion. The air hole is located on the connecting portion. The sealing ring includes a first sealing portion that mates with the first tooth portion and a second sealing portion that mates with the second tooth portion. The bearing sealing flow channel is located between the first tooth portion and the first sealing portion. The return flow channel is located between the second tooth portion and the second sealing portion. A cavity communicating with the gas flow channel is formed on the sealing ring. The cavity is located between the first sealing portion and the second sealing portion. The opening position of the cavity is opposite to the position of the air hole.

[0013] Optionally, a guide slope is provided at one end of the first sealing part near the second sealing part, and the guide slope is inclined from the air hole toward the concave cavity toward the bearing cavity.

[0014] According to another aspect of the present invention, an aircraft engine is also provided, which includes the above-described bearing cavity sealing structure.

[0015] In summary, this application includes at least one of the following beneficial technical effects:

[0016] 1. By setting up a bearing sealing flow channel and a return flow channel, the bearing cavity is sealed by the grate teeth. The sealing air passes through the gap between the grate teeth. Part of the sealing air returns to the flow channel through the return flow channel, and the other part of the sealing air enters the bearing cavity through the bearing sealing flow channel, which can maintain the balance of the ventilation system.

[0017] 2. By setting up the first air guide unit, on the one hand, the airflow resistance near the bearing side can be increased, reducing the gas flow velocity from the bearing sealing channel into the bearing cavity. On the other hand, the airflow direction is changed so that the airflow no longer blows directly onto the bearing. Even if the sealing gap is large, the lubricating oil mist in the bearing cavity will not be lost too quickly due to the sealing airflow. When the lubricating oil in the bearing cavity is interrupted, the oil mist in the bearing cavity can be maintained for a longer time, which is beneficial to the bearing cavity's resistance to oil cut-off.

[0018] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0020] Figure 1 This is a schematic diagram of the structure of a preferred embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of a preferred embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of a preferred embodiment three of the present invention.

[0023] Legend:

[0024] 1. Journal; 2. Bearing housing; 3. Bearing cavity; 4. Sealing ring; 41. First sealing part; 42. Second sealing part; 5. Grate teeth; 51. First tooth part; 52. Second tooth part; 6. Air hole; 7. Guide slope; 8. Second air guiding unit; 9. First air guiding unit; 91. Support part; 92. Air guiding part; 93. Guide hole; 94. Air guiding protrusion; 10. Cavity. Detailed Implementation

[0025] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0026] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0027] This application discloses a bearing cavity sealing structure and an aero-engine.

[0028] Example 1, refer to Figure 1 The bearing cavity sealing structure includes a rotor and a stator. A journal 1 is formed on the rotor, and a bearing housing 2 is provided on the stator. A bearing cavity 3 is formed between the bearing housing 2 and the journal 1, and a bearing is installed in the bearing cavity 3. A sealing ring 4 is provided on the stator, and a grate 5 that cooperates with the sealing ring 4 is provided on the rotor. The grate 5 has air holes 6. A gas flow channel is formed between the sealing ring 4 and the grate 5. The gas flow channel includes a bearing sealing flow channel from the air holes 6 to the side closer to the bearing cavity 3 and a return flow channel from the air holes 6 to the side away from the bearing cavity 3.

[0029] In this embodiment, the vent 6 is connected to the sealing airflow drawn from the engine flow channel. Part of the gas enters the bearing cavity 3 through the bearing sealing channel, and the other part returns to the main flow channel through the return flow channel. The airflow generated by the vent 6 effectively separates the bearing cavity 3 from the external environment through the gas flow channel formed between the grates 5 on the rotor and the sealing rings 4 on the stator. The airflow guided by the vent 6 flows towards the bearing sealing channel, blocking dust and impurities from entering the bearing cavity 3, protecting the cleanliness and operational efficiency of the bearing; on the other hand, it flows towards the return flow channel, helping to dissipate heat and pressure within the bearing cavity 3, thereby enhancing the bearing's heat dissipation and overall sealing performance, extending bearing life, and improving the reliability and stability of the equipment.

[0030] A first air guiding unit 9 is provided at one end of the sealing ring 4 near the bearing cavity 3. The first air guiding unit 9 includes a support part 91 connected to the sealing ring 4 and an air guiding part 92 connected to the support part 91. A guide hole 93 perpendicular to the rotor axis is provided on the support part 91. The guide hole 93 communicates with the bearing cavity 3. One end of the air guiding part 92 extends into the bearing sealing flow channel to guide the airflow in the bearing sealing flow channel into the guide hole 93.

[0031] In this embodiment, after the airflow from the bearing sealing channel enters the first air guiding unit 9, part of the airflow is blocked by the air guiding part 92 and enters the guide hole 93, and then enters the bearing cavity 3 through the air guiding hole 6. This slows down the gas flow rate and prevents the airflow from directly blowing onto the bearing. The first air guiding unit 9 achieves efficient airflow management through the combination of the support part 91 and the air guiding part 92. The air guiding part 92 extends into the bearing sealing channel, effectively capturing and guiding the airflow in the channel into the guide hole 93. In this way, the airflow is directly guided from the bearing sealing channel to the bearing cavity 3, helping to dissipate heat and pressure from the bearing cavity 3, while preventing dust and impurities from entering the bearing cavity 3. This not only improves the heat dissipation efficiency of the bearing, but also enhances the sealing performance of the bearing cavity 3, thereby effectively extending the service life of the bearing.

[0032] Multiple first air guiding units 9 are arranged along the axial direction of the rotor. Air guiding chambers are formed between the air guiding sections 92 of adjacent first guiding units, and guide holes 93 communicate with the air guiding chambers. It is understood that two, three, or more first guiding units can be provided. By setting multiple first guiding units, the airflow within the bearing sealing channel is guided step-by-step, allowing the airflow within the bearing sealing channel to gradually enter the bearing cavity 3 through the guide holes 93, effectively guiding the airflow and improving its uniformity. The communication between the guide holes 93 and the air guiding chambers further ensures smooth airflow. Optionally, the transition between the air guiding section 92 and the support section 91 is an arc to improve the smoothness of the airflow.

[0033] The grate teeth 5 are provided with air-guiding protrusions 94, which extend into the air-guiding cavity, forming a guiding channel between the protrusions and the first air-guiding unit 9. The top of the protrusions is matched with the position of the guide holes 93. This design is mainly aimed at further optimizing the guidance and control of airflow. By providing air-guiding protrusions 94 on the grate teeth 5 and extending them into the air-guiding cavity to form a guiding channel, airflow can be effectively guided and the stability of the flow can be enhanced. The guiding channel between the protrusions and the first air-guiding unit 9 helps to more accurately control the direction and speed of the airflow, thereby maximizing the efficiency of the power system.

[0034] The comb 5 includes a first tooth portion 51, a second tooth portion 52, and a connecting portion connecting the first tooth portion 51 and the second tooth portion 52. The inner diameter of the first tooth portion 51 is smaller than the inner diameter of the second tooth portion 52. An air hole 6 is located on the connecting portion. The sealing ring 4 includes a first sealing portion 41 that mates with the first tooth portion 51 and a second sealing portion 42 that mates with the second tooth portion 52. The bearing sealing flow channel is located between the first tooth portion 51 and the first sealing portion 41, and the return flow channel is located between the second tooth portion 52 and the second sealing portion 42. By dividing the comb 5 into a first tooth portion 51, a second tooth portion 52, and a connecting portion, and by providing an air hole 6 on the connecting portion, a design is implemented that allows for the control of airtightness of the first tooth portion 51 and the second tooth portion 52 with different inner diameters. This configuration allows for control of airtightness at the connecting portion through the air hole 6, which helps maintain a stable air pressure environment for the bearing system. The first sealing portion 41 of the sealing ring 4 mates with the first toothed portion 51, and the second sealing portion 42 mates with the second toothed portion 52, ensuring a tight seal and effectively preventing external impurities from entering the bearing system, reducing wear and increasing bearing life. The bearing sealing flow channel is located between the first toothed portion 51 and the first sealing portion 41, while the return flow channel is located between the second toothed portion 52 and the second sealing portion 42. This helps guide and control the flow of lubricating oil, improving the bearing's lubrication effect.

[0035] Example 2, refer to Figure 2The bearing cavity sealing structure includes a rotor and a stator. A journal 1 is formed on the rotor, and a bearing housing 2 is provided on the stator. A bearing cavity 3 is formed between the bearing housing 2 and the journal 1, and a bearing is installed in the bearing cavity 3. A sealing ring 4 is provided on the stator, and a grate 5 that cooperates with the sealing ring 4 is provided on the rotor. The grate 5 has air holes 6. A gas flow channel is formed between the sealing ring 4 and the grate 5. The gas flow channel includes a bearing sealing flow channel from the air holes 6 to the side closer to the bearing cavity 3 and a return flow channel from the air holes 6 to the side away from the bearing cavity 3.

[0036] In this embodiment, the vent 6 is connected to the sealing airflow drawn from the engine flow channel. Part of the gas enters the bearing cavity 3 through the bearing sealing channel, and the other part returns to the main flow channel through the return flow channel. The airflow generated by the vent 6 effectively separates the bearing cavity 3 from the external environment through the gas flow channel formed between the grates 5 on the rotor and the sealing rings 4 on the stator. The airflow guided by the vent 6 flows towards the bearing sealing channel, blocking dust and impurities from entering the bearing cavity 3, protecting the cleanliness and operational efficiency of the bearing; on the other hand, it flows towards the return flow channel, helping to dissipate heat and pressure within the bearing cavity 3, thereby enhancing the bearing's heat dissipation and overall sealing performance, extending bearing life, and improving the reliability and stability of the equipment.

[0037] A first air guiding unit 9 is provided at one end of the sealing ring 4 near the bearing cavity 3. The first air guiding unit 9 includes a support part 91 connected to the sealing ring 4 and an air guiding part 92 connected to the support part 91. A guide hole 93 perpendicular to the rotor axis is provided on the support part 91. The guide hole 93 communicates with the bearing cavity 3. One end of the air guiding part 92 extends into the bearing sealing flow channel to guide the airflow in the bearing sealing flow channel into the guide hole 93.

[0038] In this embodiment, after the airflow from the bearing sealing channel enters the first air guiding unit 9, part of the airflow is blocked by the air guiding part 92 and enters the guide hole 93, and then enters the bearing cavity 3 through the air guiding hole 6. This slows down the gas flow rate and prevents the airflow from directly blowing onto the bearing. The first air guiding unit 9 achieves efficient airflow management through the combination of the support part 91 and the air guiding part 92. The air guiding part 92 extends into the bearing sealing channel, effectively capturing and guiding the airflow in the channel into the guide hole 93. In this way, the airflow is directly guided from the bearing sealing channel to the bearing cavity 3, helping to dissipate heat and pressure from the bearing cavity 3, while preventing dust and impurities from entering the bearing cavity 3. This not only improves the heat dissipation efficiency of the bearing, but also enhances the sealing performance of the bearing cavity 3, thereby effectively extending the service life of the bearing.

[0039] Multiple first air guiding units 9 are arranged along the axial direction of the rotor. Air guiding chambers are formed between the air guiding sections 92 of adjacent first guiding units, and guide holes 93 communicate with the air guiding chambers. It is understood that two, three, or more first guiding units can be provided. By setting multiple first guiding units, the airflow within the bearing sealing channel is guided step-by-step, allowing the airflow within the bearing sealing channel to gradually enter the bearing cavity 3 through the guide holes 93, effectively guiding the airflow and improving its uniformity. The communication between the guide holes 93 and the air guiding chambers further ensures smooth airflow. Optionally, the transition between the air guiding section 92 and the support section 91 is an arc to improve the smoothness of the airflow.

[0040] The grate teeth 5 are provided with air-guiding protrusions 94, which extend into the air-guiding cavity, forming a guiding channel between the protrusions and the first air-guiding unit 9. The top of the protrusions is matched with the position of the guide holes 93. This design is mainly aimed at further optimizing the guidance and control of airflow. By providing air-guiding protrusions 94 on the grate teeth 5 and extending them into the air-guiding cavity to form a guiding channel, airflow can be effectively guided and the stability of the flow can be enhanced. The guiding channel between the protrusions and the first air-guiding unit 9 helps to more accurately control the direction and speed of the airflow, thereby maximizing the efficiency of the power system.

[0041] The comb 5 includes a first tooth portion 51, a second tooth portion 52, and a connecting portion connecting the first tooth portion 51 and the second tooth portion 52. The inner diameter of the first tooth portion 51 is smaller than the inner diameter of the second tooth portion 52. An air hole 6 is located on the connecting portion. The sealing ring 4 includes a first sealing portion 41 that mates with the first tooth portion 51 and a second sealing portion 42 that mates with the second tooth portion 52. The bearing sealing flow channel is located between the first tooth portion 51 and the first sealing portion 41, and the return flow channel is located between the second tooth portion 52 and the second sealing portion 42. By dividing the comb 5 into a first tooth portion 51, a second tooth portion 52, and a connecting portion, and by providing an air hole 6 on the connecting portion, a design is implemented that allows for the control of airtightness of the first tooth portion 51 and the second tooth portion 52 with different inner diameters. This configuration allows for control of airtightness at the connecting portion through the air hole 6, which helps maintain a stable air pressure environment for the bearing system. The first sealing portion 41 of the sealing ring 4 mates with the first toothed portion 51, and the second sealing portion 42 mates with the second toothed portion 52, ensuring a tight seal and effectively preventing external impurities from entering the bearing system, reducing wear and increasing bearing life. The bearing sealing flow channel is located between the first toothed portion 51 and the first sealing portion 41, while the return flow channel is located between the second toothed portion 52 and the second sealing portion 42. This helps guide and control the flow of lubricating oil, improving the bearing's lubrication effect.

[0042] A cavity 10 communicating with the gas flow channel is formed on the sealing ring 4, and the opening of the cavity 10 is opposite to the position of the vent 6. A guide slope 7 is provided at one end of the first sealing part 41 near the second sealing part 42, and the guide slope 7 is inclined from the vent 6 toward the cavity 10 toward the bearing cavity 3.

[0043] After the gas enters from the vent 6 between the grate 5 and the sealing ring 4, it directly enters the cavity 10, and then flows through the cavity 10 into the bearing sealing channel and the return channel, thus acting as a buffer. Its function is to optimize the guidance and control of gas flow. The connectivity between the cavity 10 and the gas channel helps guide the gas flow in a specific direction, while the guide ramp 7 further guides the gas flow into the cavity 10. In this way, the design achieves effective control of gas flow, ensuring normal gas flow between the sealing ring 4 and the bearing cavity 3, improving airtightness and sealing effect.

[0044] The comb 5 includes a first tooth 51, a second tooth 52, and a connecting portion connecting the first tooth 51 and the second tooth 52. The inner diameter of the first tooth 51 is smaller than the inner diameter of the second tooth 52. The air hole 6 is located on the connecting portion. The sealing ring 4 includes a first sealing portion 41 that mates with the first tooth 51 and a second sealing portion 42 that mates with the second tooth 52. The bearing sealing flow channel is located between the first tooth 51 and the first sealing portion 41. The return flow channel is located between the second tooth 52 and the second sealing portion 42. A cavity 10 communicating with the gas flow channel is formed on the sealing ring 4. The cavity 10 is located between the first sealing portion 41 and the second sealing portion 42. The opening position of the cavity 10 is opposite to the position of the air hole 6.

[0045] Example 3, refer to Figure 3 The difference between this embodiment and embodiment two is that the bearing includes an outer ring, rolling elements and an inner ring. The outer ring is connected to the bearing housing 2, and the inner ring is connected to the rotor. A second air guide unit 8 is provided on the side of the inner ring near the grate 5. The second air guide unit 8 is located between the bearing sealing flow channel outlet and the rolling elements.

[0046] The second air guide unit 8 is located between the bearing sealing flow channel outlet and the rolling element, and can block the airflow to prevent the airflow from blowing directly onto the rolling element, thereby preventing the bearing cage from becoming unstable under the action of the airflow. It can be understood that the second air guide unit 8 is a ring structure surrounding the rotor, and the cross-section of the second air guide unit 8 can be rectangular, trapezoidal, or triangular.

[0047] According to another aspect of the present invention, an aircraft engine is also provided, which includes the above-described bearing cavity sealing structure.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A bearing cavity sealing structure, characterized in that: It includes a rotor and a stator. A journal (1) is formed on the rotor, and a bearing housing (2) is provided on the stator. A bearing cavity (3) is formed between the bearing housing (2) and the journal (1), and a bearing is installed in the bearing cavity (3). A sealing ring (4) is provided on the stator, and a grating tooth (5) that cooperates with the sealing ring (4) is provided on the rotor. A vent hole (6) is provided on the grating tooth (5). A gas flow channel is formed between the sealing ring (4) and the grating tooth (5). The gas flow channel includes a bearing sealing flow channel from the vent hole (6) to the side close to the bearing cavity (3) and a return flow channel from the vent hole (6) to the side away from the bearing cavity (3). A first air guiding unit (9) is provided at one end of the sealing ring (4) near the bearing cavity (3). The first air guiding unit (9) includes a support part (91) connected to the sealing ring (4) and an air guiding part (92) connected to the support part (91). A guide hole (93) perpendicular to the rotor axis is provided on the support part (91). The guide hole (93) communicates with the bearing cavity (3). One end of the air guiding part (92) extends into the bearing sealing flow channel to guide the airflow in the bearing sealing flow channel into the guide hole (93).

2. The bearing cavity sealing structure according to claim 1, characterized in that, The first air guiding unit (9) is provided with multiple units along the axial direction of the rotor. An air guiding cavity is formed between the air guiding parts (92) of adjacent first guiding units, and the guide hole (93) is connected to the air guiding cavity.

3. The bearing cavity sealing structure according to claim 2, characterized in that, The grating teeth (5) are provided with air guide protrusions (94), which extend into the air guide cavity, and a guide channel is formed between the guide protrusions and the first air guide unit (9).

4. The bearing cavity sealing structure according to claim 3, characterized in that, The top of the guide protrusion is positioned to match the position of the guide hole (93).

5. The bearing cavity sealing structure according to claim 4, characterized in that, The bearing includes an outer ring, rolling elements and an inner ring. The outer ring is connected to the bearing housing (2) and the inner ring is connected to the rotor. A second air guide unit (8) is provided on the side of the inner ring near the grate (5). The second air guide unit (8) is located between the bearing sealing flow channel outlet and the rolling elements.

6. The bearing cavity sealing structure according to claim 1, characterized in that, The sealing ring (4) has a cavity (10) that communicates with the gas flow channel, and the opening of the cavity (10) is opposite to the position of the vent (6).

7. The bearing cavity sealing structure according to claim 1, characterized in that, The comb teeth (5) include a first tooth (51), a second tooth (52), and a connecting part connecting the first tooth (51) and the second tooth (52). The inner diameter of the first tooth (51) is smaller than the inner diameter of the second tooth (52). The air hole (6) is located on the connecting part. The sealing ring (4) includes a first sealing part (41) that mates with the first tooth (51) and a second sealing part (42) that mates with the second tooth (52). The bearing sealing flow channel is located between the first tooth (51) and the first sealing part (41), and the return flow channel is located between the second tooth (52) and the second sealing part (42).

8. The bearing cavity sealing structure according to claim 7, characterized in that, The comb (5) includes a first tooth (51), a second tooth (52), and a connecting part connecting the first tooth (51) and the second tooth (52). The inner diameter of the first tooth (51) is smaller than the inner diameter of the second tooth (52). The air hole (6) is located on the connecting part. The sealing ring (4) includes a first sealing part (41) that cooperates with the first tooth (51) and a second sealing part (42) that cooperates with the second tooth (52). The bearing sealing flow channel is located between the first tooth (51) and the first sealing part (41). The return flow channel is located between the second tooth (52) and the second sealing part (42). A cavity (10) communicating with the gas flow channel is formed on the sealing ring (4). The cavity (10) is located between the first sealing part (41) and the second sealing part (42). The opening position of the cavity (10) is opposite to the position of the air hole (6).

9. The bearing cavity sealing structure according to claim 8, characterized in that, The first sealing part (41) is provided with a guide slope (7) at one end near the second sealing part (42). The guide slope (7) is inclined from the air hole (6) toward the cavity (10) toward the bearing cavity (3).

10. An aircraft engine, characterized in that, Includes the bearing cavity sealing structure as described in any one of claims 1-9.

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