Sealing structure suitable for low-altitude aircraft

Abstract

The sealing structure suitable for the low-altitude aircraft comprises a rotating shaft, the rotating shaft is coaxially sleeved with a sealing lining, the rotating shaft is provided with a plurality of sealing labyrinth teeth arranged in the axial direction, the outer circumferential faces of the sealing labyrinth teeth are in clearance fit with the inner ring face of the sealing lining, and the sealing lining is provided with a rotating piece and a protruding piece; the rotating part is located in front of a gap between the sealing labyrinth and the sealing lining, the rotating part can scatter water flowing to the gap between the sealing labyrinth and the sealing lining through rotation to enable the water to change the flowing direction, and the protruding part is located behind the rotating part and also located in front of the gap between the sealing labyrinth and the sealing lining. The protruding piece protrudes towards the gap between the sealing labyrinth and the sealing bush and is used for blocking water flow towards the gap between the sealing labyrinth and the sealing bush. The problem of absorbing liquid water and water vapor of the low-altitude aircraft can be effectively solved, the sealing effect of the labyrinth structure is kept, and the leakage amount of the structure is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of aeroengine seals, and particularly relates to a sealing structure suitable for low-altitude aircraft. Background Art

[0002] With the country's strong promotion of the development of the low-altitude economy, the downstream scenarios of unmanned aerial vehicles (UAVs) are constantly increasing, and the application environment of UAVs is diversified and complex. For aircraft below 1,000 meters, the key challenges for sealing change from air to water. In the low-altitude environment, the impact of liquid water and water vapor on the sealing structure becomes an important factor in leakage. Moreover, the efficiency of the aircraft highly depends on the leakage of gas through the radial clearance of the moving blades, the dovetail joints at the blade roots, and the labyrinth teeth at the roots of the stationary blades. Facing the requirements of the low-altitude economy for long endurance and low energy consumption of low-altitude aircraft, innovative designs targeted at the problems of liquid water and water vapor must be made on the original sealing structure.

[0003] Comparing many sealing structures, labyrinth sealing has the advantages of low cost, reliable structure, and simple maintenance, which are easy to promote and use, and is more suitable for mass production required by the development of the low-altitude economy. The performance of labyrinth sealing is limited by the radial clearance between the rotating parts and the stationary wall. Ideally, zero clearance of the labyrinth teeth can avoid performance loss. However, due to the vibration, thermal deformation, and creep occurring during the operation of the rotating parts and the stationary parts, as well as the manufacturing tolerance of the labyrinth sealing itself and the tolerance required during the assembly process, a certain clearance must be retained during use. How to improve the sealing performance of traditional sealing structures has become an important issue. One method is to change the flow path of the labyrinth tooth structure to improve leakage, such as the influence of the shape parameter variables of the curved flow path, staggered labyrinth sealing, and staggered labyrinth sealing on the leakage performance. The other is to set up a fluid barrier to reduce leakage with a small geometric change. However, there is still no sealing structure specifically for low-altitude aircraft. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a sealing structure suitable for low-altitude aircraft that can effectively disrupt the flow field and absorb water to address the problems of liquid water and water vapor absorption in low-altitude aircraft, aiming at the deficiencies of the above-mentioned prior art.

[0005] To achieve the above technical objectives, the technical solution adopted by the present invention is as follows:

[0006] A sealing structure applicable to low-altitude aircraft, including a rotating shaft, a sealing bushing coaxially sleeved outside the rotating shaft, a plurality of sealing labyrinth teeth arranged axially on the rotating shaft, the outer peripheral surface of the sealing labyrinth teeth is in clearance fit with the inner ring surface of the sealing bushing, a rotating member and a convex member are arranged on the sealing bushing, the rotating member is located in front of the gap between the sealing labyrinth teeth and the sealing bushing, the rotating member can disperse the water flowing into the gap between the sealing labyrinth teeth and the sealing bushing by rotation to change its flow direction, the convex member is located behind the rotating member and also in front of the gap between the sealing labyrinth teeth and the sealing bushing, and the convex member protrudes towards the gap between the sealing labyrinth teeth and the sealing bushing to block the water flow towards the gap between the sealing labyrinth teeth and the sealing bushing.

[0007] To optimize the above technical solution, the specific measures taken also include:

[0008] An absorbent material is arranged between the inner ring surface of the above-mentioned sealing bushing between the rotating member and the convex member, and the absorbent material is used to absorb the water sputtered onto the inner ring surface of the sealing bushing.

[0009] The above-mentioned convex member is an arc-shaped member, and the bending direction of the convex member is: the lower end of the convex member bends forward.

[0010] The above-mentioned rotating member includes a threaded tube, a fan surface, a chassis, a threaded post and a connecting rod. Among them, the fan surface and the chassis are located below the sealing bushing, the connecting rod is located above the sealing bushing, a through hole penetrating the sealing bushing up and down is opened on the sealing bushing, the threaded tube is fixed in the through hole, the fan surface is located in front of the gap between the sealing labyrinth teeth and the sealing bushing, the fan shaft of the fan surface is fixedly connected to the lower end of the threaded post, the threaded post is rotatably installed in the threaded tube, the upper end of the threaded post is circumferentially rotatable and axially positioned and connected to one end of the connecting rod, the other end of the connecting rod is connected to the chassis, the chassis is located below the absorbent material. When the fan surface is impacted by water flow from front to back, the rotation of the fan surface can make the threaded post rotate forward and move upward in the threaded tube, and the connecting rod moves upward to pull the chassis to squeeze the absorbent material, so that the absorbent material is dehydrated. When the impact of the water flow on the fan surface from front to back decreases, the self-weight of the fan surface, the chassis and the connecting rod makes the threaded post rotate reversely and move downward in the threaded tube, and the chassis relaxes the absorbent material.

[0011] The above-mentioned absorbent material is sponge.

[0012] The above-mentioned threaded tube is a double-threaded tube with threads arranged both inside and outside, the through hole is a threaded hole, and the outer thread of the threaded tube is matched with the thread of the through hole to make the threaded tube and the through hole be sealed and connected.

[0013] The above-mentioned chassis is made of a grid-shaped rigid material.

[0014] The above-mentioned fan surface is composed of a plurality of fan blades connected to the fan shaft at equal angles.

[0015] The above-mentioned convex member is a rigid material with a radial curvature between 45° and 50°.

[0016] A rotating part is provided between the gaps of the first two sealing labyrinth teeth and the sealing bushing described above. Among them, only the frontmost rotating part is provided with a threaded pipe, a fan surface, a chassis, a threaded post and a connecting rod, and the second rotating part is only provided with a fan surface, without a threaded pipe, a chassis, a threaded post and a connecting rod.

[0017] The beneficial effects of the present invention are as follows: The labyrinth tooth sealing structure containing the bushing installation structure in the present invention is used to absorb the moisture in the channel at low altitude. The rotating part breaks the water and disturbs the water flow at the channel entrance, and the convex part causes the disturbed water flow to flow back and be fully absorbed by the sponge absorbent material on the water permeable surface. To further absorb the moisture in the channel, the rotating part absorbs the kinetic energy of the water flow while breaking the water through the lower fan surface, causing the rotating part to rotate upward through the bidirectional threaded hole, causing the grid chassis to be lifted upward at the same time, squeezing the sponge absorbent material, and being able to restore the water absorption performance of the material. The lower fan surface of the rotating part, the water permeable surface and the convex part are installed between the inlet labyrinth tooth structure and the second labyrinth tooth, on the one hand, absorbing the moisture after the sponge absorbent material at the inlet is squeezed, and on the other hand, absorbing the remaining moisture in the channel. By repeatedly absorbing water, the sealing effect of the labyrinth tooth structure is maintained, and the leakage amount of the structure is reduced. Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of the present invention;

[0019] Among them, the reference numerals are: rotating shaft 1, sealing labyrinth tooth 2, sealing bushing 3, perforation 31, rotating part 4, threaded pipe 41, fan surface 42, chassis 43, threaded post 44, connecting rod 45, convex part 5, absorbent material 6, water permeable surface 7. Detailed Embodiments

[0020] In order to make the purpose, technical solution and advantages of the present application clearer, the following describes and explains the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0021] Obviously, the drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, the present application can also be applied to other similar scenarios based on these drawings. In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for those of ordinary skill in the art related to the content disclosed in the present application, some designs, manufacturing or production changes made on the basis of the technical content disclosed in the present application are only conventional technical means and should not be understood as the content disclosed in the present application being insufficient.

[0022] As used herein, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of the present application. The phrase appearing at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in the present application can be combined with other embodiments without conflict.

[0023] Unless otherwise defined, technical terms or scientific terms involved in the present application shall have the ordinary meanings understood by those of ordinary skill in the technical field to which the present application pertains. The words such as "a", "an", "one", "the", etc. involved in the present application do not indicate a limitation in quantity and can represent a singular or plural number. The terms "comprising", "including", "having" and any variations thereof involved in the present application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or device comprising a series of steps or units (units) is not limited to the listed steps or units, but may further include steps or units not listed, or may further include other steps or units inherent to these processes, methods, products or devices. The terms "connected", "coupled", etc. involved in the present application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The term "plurality" / "several" involved in the present application means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships can exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in the present application are only used to distinguish similar objects and do not represent a specific order for the objects.

[0024] A labyrinth seal structure with a bushing installation structure according to the present invention includes a rotating shaft 1. A seal bushing 3 is coaxially sleeved outside the rotating shaft 1. A plurality of axially arranged labyrinth teeth 2 are provided on the rotating shaft 1. The outer peripheral surface of the labyrinth teeth 2 is in clearance fit with the inner ring surface of the seal bushing 3. A rotating member 4 and a convex member 5 are provided on the seal bushing 3. The water-breaking effect of the rotating member 4 and the convex member 5 cooperates with a water-absorbing material 6 to maintain good sealing performance of the labyrinth seal structure.

[0025] In the embodiment, the lower end fan surface 42 of the sealing labyrinth rotating part 4 at the entrance slows down the water flow speed by breaking the water, disturbs the water flow impact, facilitates the water to be fully absorbed by the water absorption material 6 through the water permeable surface 7. The fan surface 42 simultaneously absorbs the water flow kinetic energy when breaking the water, enabling the rotating part to rotate upward through the perforation 31. The chassis 43 also rotates upward and rises with the rotating part 4, squeezing the water absorption material 6 with the sealing bushing 3, enabling the water absorption material 6 to resume its water absorption performance. After draining the water, it rotates downward under the action of gravity to continue absorbing water.

[0026] In the embodiment, the fan surface 42 is made of a rigid material to fully absorb the water flow kinetic energy. The chassis 43 is a grid-shaped rigid material to facilitate the absorption of water through the water permeable surface.

[0027] In the embodiment, the raised part 5 is made of a rigid material with a radial curvature between 45° and 50°, causing the water flow to flow back to the water permeable surface and be fully absorbed by the water absorption material 6.

[0028] In the embodiment, a fan surface 42, a water absorption material 6, and a rear raised part 5 are installed between the entrance sealing labyrinth 2 and the next sealing labyrinth 2. The fan surface 42 breaks the water and disturbs the flow field, and the raised part 5 blocks the water flow in the channel to facilitate the water absorption material 6 to absorb the remaining water in the channel.

[0029] The labyrinth sealing structure with the additional structure on the bushing of the present invention disturbs the water flow field in an environment with a large water flow impact during low-altitude flight, weakens the influence of the water flow impact on the leakage amount of the labyrinth sealing structure, and at the same time utilizes the water flow impact kinetic energy to repeatedly absorb the water in the channel, effectively maintaining the sealing performance of the labyrinth sealing structure, weakening the kinetic energy of the water flow field, and reducing the leakage amount of the labyrinth sealing structure.

[0030] It can be understood that the above specific description of the present invention is only for explaining the present invention and is not limited to the technical solutions described in the implementation of the calculation method of the present invention. Those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced to achieve the same technical effects; as long as it meets the requirements of the calculation method, it is within the protection scope of the present invention.

Claims

1. A sealing structure suitable for low-altitude aircraft, comprising a rotating shaft (1), a sealing bushing (3) is coaxially sleeved outside the rotating shaft (1), a plurality of axially arranged sealing grate teeth (2) are arranged on the rotating shaft (1), the outer peripheral surface of the sealing grate teeth (2) and the inner annular surface of the sealing bushing (3) are clearance-matched, and the characteristics are: A rotating member (4) and a protruding member (5) are provided on the sealing bushing (3). The rotating member (4) is located in front of the gap between the sealing grate teeth (2) and the sealing bushing (3). The rotating member (4) can disperse the water flowing into the gap between the sealing grate teeth (2) and the sealing bushing (3) by rotating, thereby changing the flow direction. The protruding member (5) is located behind the rotating member (4) and is also located in front of the gap between the sealing grate teeth (2) and the sealing bushing (3). The protruding member (5) protrudes toward the gap between the sealing grate teeth (2) and the sealing bushing (3) to block the water from flowing into the gap between the sealing grate teeth (2) and the sealing bushing (3).

2. The sealing structure suitable for low-altitude aircraft according to claim 1 is characterized in that: The inner ring surface of the sealing bushing (3) is provided with a water-absorbing material (6) between the rotating part (4) and the protruding part (5), and the water-absorbing material (6) is used to absorb water splashed onto the inner ring surface of the sealing bushing (3).

3. A sealing structure suitable for low-altitude aircraft according to claim 2, characterized in that: The protruding piece (5) is an arc-shaped piece, and the bending direction of the protruding piece (5) is: the lower end of the protruding piece (5) bends forward.

4. The sealing structure suitable for low-altitude aircraft according to claim 2 is characterized in that: The rotating member (4) comprises a threaded tube (41), a fan surface (42), a chassis (43), a threaded column (44) and a connecting rod (45), wherein the fan surface (42) and the chassis (43) are located below the sealing bushing (3), the connecting rod (45) is located above the sealing bushing (3), the sealing bushing (3) is provided with a through hole (31) which passes through the sealing bushing (3) from top to bottom, the threaded tube (41) is fixed in the through hole (31), the fan surface (42) is located in front of the gap between the sealing comb teeth (2) and the sealing bushing (3), the fan shaft of the fan surface (42) is fixedly connected to the lower end of the threaded column (44), the threaded column (44) can be rotatably installed in the threaded tube (41), and the upper end of the threaded column (44) is connected to the threaded tube (41). One end of the connecting rod (45) is rotatable in the circumferential direction and axially positioned, and the other end of the connecting rod (45) is connected to the chassis (43). The chassis (43) is located below the water-absorbing material (6). When the fan surface (42) is impacted by the water flow from front to back, the fan surface (42) rotates to enable the threaded column (44) to move forward in the threaded tube (41), and the connecting rod (45) moves upward to pull the chassis (43) to squeeze the water-absorbing material (6), so that the water-absorbing material (6) is dehydrated. When the water flow impacting the fan surface (42) from front to back decreases, the self-weight of the fan surface (42), the chassis (43) and the connecting rod (45) causes the threaded column (44) to reverse and move downward in the threaded tube (41), and the chassis (43) releases the water-absorbing material (6).

5. The sealing structure suitable for low-altitude aircraft according to claim 2 is characterized in that: The water absorbing material (6) is a sponge.

6. The sealing structure suitable for low-altitude aircraft according to claim 4 is characterized by: The threaded tube (41) is a bidirectional threaded tube with threads both inside and outside, the through hole (31) is a threaded hole, and the outer thread of the threaded tube (41) matches the thread of the through hole (31), so that the threaded tube (41) and the through hole (31) are sealed and connected.

7. The sealing structure suitable for low-altitude aircraft according to claim 4 is characterized by: The chassis (43) is made of grid-shaped rigid material.

8. The sealing structure suitable for low-altitude aircraft according to claim 4 is characterized by: The fan surface (42) is composed of a plurality of fan blades of equal curvature connected to a fan shaft.

9. The sealing structure suitable for low-altitude aircraft according to claim 4 is characterized by: The protrusion (5) is made of a rigid material with a radial curvature between 45° and 50°.

10. The sealing structure suitable for low-altitude aircraft according to claim 4, characterized in that: A rotating member (4) is arranged in front of the gap between the first two sealing comb teeth (2) and the sealing bushing (3), wherein only the first rotating member (4) is provided with a threaded tube (41), a sector (42), a chassis (43), a threaded column (44) and a connecting rod (45), and the second rotating member (4) is only provided with a sector (42) and is not provided with a threaded tube (41), a chassis (43), a threaded column (44) and a connecting rod (45).

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