Gas flow path sealing device

Abstract

The present application relates to the technical field of gas sealing, and particularly relates to a gas flow path sealing device. The gas flow path sealing device comprises a comb seal structure, a brush seal structure arranged on one side of the comb seal structure and fixedly connected with the comb seal structure, and a fingertip seal structure arranged on the side of the brush seal structure away from the comb seal structure, wherein the fingertip seal structure comprises a plurality of fingertip foils, and the plurality of fingertip foils are coaxially arranged on a rotor together with the comb seal structure and the brush seal structure; wherein the comb seal structure is arranged on the high-pressure side of the rotor, and the fingertip seal structure is arranged on the low-pressure side of the rotor. By sequentially arranging the comb seal structure, the brush seal structure and the fingertip seal structure, and arranging the comb seal structure on the high-pressure side and the fingertip seal structure on the low-pressure side, the fluid pressure can be reduced by the comb seal structure, and then the fluid can pass through the brush seal structure and the fingertip seal structure in sequence, so that the sealing effect is improved.

Description

Technical Field

[0001] This invention relates to the field of gas sealing technology, and more specifically to a gas flow path sealing device. Background Technology

[0002] The function of an aircraft engine's air system is mainly regulated by the sealing devices within the system. Currently, the commonly used gas flow path sealing devices are toothed seals, brush seals, and fingertip seals.

[0003] Grate seals are a commonly used type of non-contact seal. When fluid enters the gap between the rotor and stator, a vortex flow is formed between the grates, causing the fluid to produce a self-sealing effect, thereby gradually reducing the fluid pressure between each tooth and achieving a sealing effect.

[0004] A brush seal consists of a front baffle, a rear baffle, and tens of thousands of fine metal wires arranged evenly and tightly between the two, all welded together. The brush wires contact the sealing raceway to form a sealing interface. As an interference-fit seal, compared to a toothed seal, the leakage of a brush seal is approximately 1 / 10 to 1 / 2 that of a toothed seal.

[0005] The fingertip seal is similar in structure to the brush seal, consisting of a front baffle, several layers of fingertip sheets, and a rear baffle, connected by riveting or welding. The several layers of fingertip sheets contact the runway to form a sealing interface. Due to the flexibility of the fingertip sheets, the fingertip seal can adapt to the relative displacement changes of the rotor caused by assembly, imbalance effects, and thermal effects, maintaining excellent sealing performance for a long time.

[0006] However, rotor vibration and misalignment cause wear on the grate teeth and coating, requiring a considerable gap between the rotor and stator. This results in a weaker gas flow path sealing effect compared to brush seals and fingertip seals. Under high pressure differential conditions, brush seals suffer from significant gaps at the sealing interface due to the large number of brush filaments deforming and deflecting within the gas flow path, leading to axial leakage and poor sealing. Fingert seals also have poor pressure resistance, and their sealing performance deteriorates under high pressure differential conditions. Therefore, a sealing device with superior sealing performance is urgently needed. Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defect of poor sealing effect of the sealing device in the prior art, thereby providing a gas flow path sealing device.

[0008] To address the above problems, the present invention provides a gas flow path sealing device, comprising:

[0009] Grate-shaped sealing structure;

[0010] A brush-type sealing structure is disposed on one side of the toothed sealing structure and is fixedly connected to the toothed sealing structure;

[0011] A fingertip sealing structure is disposed on the side of the brush-type sealing structure away from the comb-type sealing structure. The fingertip sealing structure includes a plurality of fingertip sheets, which are coaxially disposed on the rotor with the comb-type sealing structure and the brush-type sealing structure.

[0012] The comb-tooth sealing structure is located on the high-pressure side of the rotor, and the fingertip sealing structure is located on the low-pressure side of the rotor.

[0013] Furthermore, a balance ring is provided between the brush-type sealing structure and the fingertip sealing structure, and a first balance cavity is provided on the side of the balance ring facing the brush-type sealing structure.

[0014] Furthermore, a baffle is provided on the side of the fingertip sealing structure away from the balance ring, and a second balance chamber is provided on the side of the baffle facing the fingertip sealing structure.

[0015] Furthermore, the fingertip beams of two adjacent fingertip sheets are misaligned.

[0016] Furthermore, a first cavity exists between the comb-shaped sealing structure and the brush-type sealing structure, and a second cavity exists between the balance ring and the fingertip sealing structure.

[0017] Furthermore, the diameters of the first balancing chamber and the second balancing chamber are smaller than the lengths of the brush seal structure and the fingertip seal structure.

[0018] Furthermore, the first cavity and the second cavity have the same outer diameter as the first balancing cavity and the second balancing cavity.

[0019] Furthermore, the brush-type sealing structure is provided with a baffle plate, which is located inside the first cavity.

[0020] Furthermore, the outer diameter surfaces of the comb-shaped sealing structure, the baffle plate, the brush-type sealing structure, the balance ring, the fingertip sealing structure, and the baffle plate are fixedly connected by welding.

[0021] Furthermore, a retaining ring is provided on the side of the baffle away from the fingertip sealing structure, and the comb sealing structure, the brush sealing structure and the fingertip sealing structure are secured to the stator mounting base by the retaining ring.

[0022] The present invention has the following advantages:

[0023] 1. This invention discloses a gas flow path sealing device, comprising: a toothed sealing structure, a brush-type sealing structure, and multiple fingertip sealing structures. The brush-type sealing structure is disposed on one side of the toothed sealing structure and fixedly connected to it; the fingertip sealing structures are disposed on the side of the brush-type sealing structure away from the toothed sealing structure, each fingertip sealing structure comprising multiple fingertip sheets, and coaxially disposed on a rotor with the toothed sealing structure and the brush-type sealing structure; wherein the toothed sealing structure is disposed on the high-pressure side of the rotor, and the multiple fingertip sealing structures are disposed on the low-pressure side of the rotor.

[0024] This gas flow path sealing device, by sequentially arranging a grate seal structure, a brush seal structure, and a fingertip seal structure, with the grate seal structure positioned on the high-pressure side and the fingertip seal structure on the low-pressure side, allows the fluid pressure to decrease through the grate seal before passing through the brush seal structure and the fingertip seal structure. As the pressure decreases, the brush seal structure and the fingertip seal structure will not leak due to excessive gas pressure, further improving the sealing effect.

[0025] 2. In this gas flow path sealing device, a first balance chamber is provided on the side of the balance ring facing the brush seal structure. The first balance chamber can reduce the frictional force caused by the balance ring on the brush seal structure, thereby effectively alleviating the hysteresis effect of the brush seal structure. Furthermore, the air in the first balance chamber can provide resistance to the brush seal structure, preventing the brush seal structure from being blown up by the gas and causing leakage.

[0026] 3. In this gas flow path sealing device, a second balancing chamber is provided on the side of the baffle facing the fingertip sealing structure. The second balancing chamber can reduce the friction caused by the baffle on the fingertip sealing structure, thereby effectively alleviating the hysteresis effect of the fingertip sealing structure.

[0027] 4. The gas flow path sealing device of this structure, by setting a first cavity and a second cavity, the first cavity can reduce the friction of the comb seal structure on the brush seal structure, and the second cavity can reduce the friction of the balance ring on the fingertip seal structure, thereby further alleviating the hysteresis effect of the brush seal structure and the fingertip seal structure.

[0028] 5. The gas flow path sealing device of this structure, by setting a baffle plate on the brush seal structure, can effectively reduce the fluid pressure and rectify the flow. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is an exploded view of the gas flow path sealing device in an embodiment of the present invention;

[0031] Figure 2 This is a cross-sectional view of the gas flow path sealing device in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the structure of the balance ring in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the fingertip beam structure in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the gas flow path sealing device in an embodiment of the present invention;

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Grate seal structure; 2. Brush seal structure; 3. Finger tip seal structure; 4. Finger tip sheet; 5. Rotor; 6. Balance ring; 7. First balance chamber; 8. Baffle; 9. Second balance chamber; 10. Finger tip beam; 11. First cavity; 12. Second cavity; 13. Flow baffle; 14. Baffle ring; 15. Stator mounting base. Detailed Implementation

[0037] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] like Figures 1 to 5 As shown, this embodiment discloses a gas flow path sealing device, including a toothed sealing structure 1, a brush sealing structure 2, and multiple fingertip sealing structures 3. The brush sealing structure 2 is disposed on one side of the toothed sealing structure 1 and is fixedly connected to the toothed sealing structure 1; the fingertip sealing structure 3 is disposed on the side of the brush sealing structure 2 away from the toothed sealing structure 1, and the fingertip sealing structure 3 includes multiple fingertip sheets 4. The fingertip sealing structure 3 is coaxially disposed on a rotor 5 with the toothed sealing structure 1 and the brush sealing structure 2; wherein, the toothed sealing structure 1 is disposed on the high-pressure side of the rotor 5, and the multiple fingertip sealing structures 3 are disposed on the low-pressure side of the rotor 5.

[0042] Specifically, the comb-tooth sealing structure 1 is located on the left side of the brush-type sealing structure 2, and the fingertip sealing structure 3 is located on the right side of the brush-type sealing structure 2. The brush-type sealing structure 2 has multiple layers of brush filaments, which can block fluid and prevent fluid leakage. The fingertip sealing structure 3 includes multiple fingertip sheets 4, which are coaxially arranged. Each fingertip sheet 4 has a fingertip beam 10 arranged circumferentially, which can block fluid and prevent fluid leakage. The comb-tooth sealing structure 1, the brush-type sealing structure 2, and the multiple fingertip sheets 4 are coaxially arranged and sleeved on the rotor 5, with the comb-tooth sealing structure 1 located on the high-pressure side of the rotor 5 and the multiple fingertip sheets 4 located on the low-pressure side of the rotor 5. Fluid enters through the gap between the teeth of the comb seal structure 1 and the rotor 5, and forms a vortex flow between the teeth, which creates a self-sealing effect and reduces the pressure of the fluid. The fluid after pressure reduction is blocked by the brush seal structure 2 and depressurized again. The fluid flowing out of the brush seal structure 2 is blocked by multiple finger-tip thin plates 4 located on the low-pressure side, thus achieving a sealing effect.

[0043] Preferably, in this embodiment, the toothed sealing structure 1 has two teeth. In other alternative embodiments, the toothed sealing structure 1 may have three or other numbers of teeth.

[0044] Preferably, in this embodiment, the fingertip sealing structure 3 includes four fingertip sheets 4. In other alternative embodiments, the fingertip sealing structure 3 includes three or five fingertip sheets 4.

[0045] Preferably, the outer diameter surfaces of the plurality of fingertip sheets 4 are welded together. In other alternative embodiments, the plurality of fingertip sheets 4 may be fixedly connected by bolts or pins.

[0046] Furthermore, the fingertip beams 10 of the two adjacent fingertip sheets 4 are misaligned.

[0047] Specifically, such as Figure 2 As shown, the fingertip beams 10 are spaced apart circumferentially along the surface of the fingertip sheet 4, with a gap between adjacent fingertip beams 10. Adjacent fingertip sheets 4 are staggered, so that the fingertip beams 10 of the two fingertip sheets 4 are also staggered. The fingertip beam 10 of the latter fingertip sheet 4 can cover the gap of the fingertip beam 10 of the former fingertip sheet 4, preventing fluid from leaking from the gap of the fingertip beam 10, thereby effectively improving the sealing effect.

[0048] Furthermore, a balance ring 6 is provided between the brush seal structure 2 and the fingertip seal structure 3, and a first balance chamber 7 is provided on the side of the balance ring 6 facing the brush seal structure 2.

[0049] Furthermore, a baffle 8 is provided on the side of the fingertip sealing structure 3 away from the balance ring 6, and a second balance chamber 9 is provided on the side of the baffle 8 facing the fingertip sealing structure 3.

[0050] Specifically, such as Figure 2 As shown, the left side of the balance ring 6 is connected to the right side of the brush seal structure 2, the left side of the brush seal structure 2 is connected to the right side of the comb seal structure 1, the right side of the balance ring 6 is connected to the left side of the fingertip seal structure 3, and the right side of the fingertip seal structure 3 is connected to the left side of the baffle 8. The first balance chamber 7 is located on the left side of the balance ring 6, and the second balance chamber 9 is located on the left side of the baffle 8. The brush filament bundle and the fingertip beam 10 are made of flexible material. After the rotor 5 rotates, the brush filament bundle and the fingertip beam 10 will be displaced in the vertical direction under the force of the rotor 5 rotation. Due to the presence of the first balance chamber 7 and the second balance chamber 9, the friction between the brush filament bundle and the balance ring 6 and the friction between the fingertip beam 10 and the baffle 8 can be effectively reduced, allowing the brush filament bundle and the fingertip beam 10 to quickly reset, thereby reducing the hysteresis effect of the brush filament bundle and the fingertip beam 10.

[0051] Simultaneously, high-pressure gas is introduced into the first balance chamber 7 and gas that has been depressurized by the comb-tooth sealing structure 1 is introduced into the second balance chamber 9. Through the throttling effect, the gas in the balance chamber has an intermediate transition pressure that follows the change of fluid pressure, balancing the gas chamber pressure on both sides of the brush filament bundle and fingertip sheet 4, and reducing the load on the rear baffle 8 caused by the fluid pressure difference of the last stage brush filament bundle or fingertip sheet 4.

[0052] Furthermore, there is a first cavity 11 between the comb-shaped sealing structure 1 and the brush-type sealing structure 2, and a second cavity 12 between the balance ring 6 and the fingertip sealing structure 3.

[0053] Specifically, the right side of the comb-tooth sealing structure 1 has a groove, which, together with the brush-type sealing structure 2, forms a first cavity 11. The right side of the balance ring 6 also has a groove, which, together with the fingertip sealing structure 3, forms a second cavity 12. The first cavity 11 and the second cavity 12 can effectively reduce the friction between the brush filament bundle and the comb-tooth sealing structure 1, as well as the friction between the fingertip beam 10 and the balance ring 6, allowing the brush filament bundle and the fingertip beam 10 to quickly reset, further reducing the hysteresis effect of the brush filament bundle and the fingertip beam 10.

[0054] Furthermore, the diameters of the first balancing chamber 7 and the second balancing chamber 9 are smaller than the lengths of the brush seal structure 2 and the fingertip seal structure 3.

[0055] Furthermore, the outer diameters of the first cavity 11 and the second cavity 12 are the same as those of the first balancing cavity 7 and the second balancing cavity 9.

[0056] Furthermore, a baffle plate 13 is provided on the brush-type sealing structure 2, and the baffle plate 13 is located inside the first cavity 11.

[0057] Specifically, the baffle plate 13 is welded and fixed to the brush seal structure 2. The baffle plate 13 can reduce the pressure of the fluid in the first cavity 11 and rectify the flow.

[0058] Furthermore, the outer diameter surfaces of the comb sealing structure 1, the baffle plate 13, the brush sealing structure 2, the balance ring 6, the fingertip sealing structure 3, and the baffle plate 8 are welded and fixedly connected.

[0059] Furthermore, a retaining ring 14 is provided on the side of the baffle 8 away from the fingertip sealing structure 3, and the toothed sealing structure 1, the brush sealing structure 2 and the fingertip sealing structure 3 are secured to the stator mounting base 15 by the retaining ring 14.

[0060] Specifically, such as Figure 5 As shown, the toothed sealing structure 1, the brush sealing structure 2, and the fingertip sealing structure 3 are mounted on the engine stator mounting base 15 by an interference fit, and the axial position is restricted by the retaining ring 14.

[0061] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A gas flow path sealing device, characterized in that, include: Grate sealing structure (1); A brush-type sealing structure (2) is disposed on one side of the toothed sealing structure (1) and is fixedly connected to the toothed sealing structure (1); A fingertip sealing structure (3) is disposed on the side of the brush sealing structure (2) away from the toothed sealing structure (1). The fingertip sealing structure (3) includes a plurality of fingertip sheets (4). The plurality of fingertip sheets (4) are coaxially disposed on the rotor (5) with the toothed sealing structure (1) and the brush sealing structure (2). The comb-tooth sealing structure (1) is located on the high-pressure side of the rotor (5), and the fingertip sealing structure (3) is located on the low-pressure side of the rotor (5). A balance ring (6) is provided between the brush sealing structure (2) and the fingertip sealing structure (3), and a first balance cavity (7) is provided on the side of the balance ring (6) facing the brush sealing structure (2); A baffle (8) is provided on the side of the fingertip sealing structure (3) away from the balance ring (6), and a second balance cavity (9) is provided on the side of the baffle (8) facing the fingertip sealing structure (3).

2. The gas flow path sealing device according to claim 1, characterized in that: The fingertip beams (10) of two adjacent fingertip sheets (4) are misaligned.

3. The gas flow path sealing device according to claim 1, characterized in that: The toothed sealing structure (1) and the brush sealing structure (2) have a first cavity (11), and the balance ring (6) and the fingertip sealing structure (3) have a second cavity (12).

4. The gas flow path sealing device according to claim 1, characterized in that: The diameters of the first balancing chamber (7) and the second balancing chamber (9) are smaller than the lengths of the brush seal structure (2) and the fingertip seal structure (3).

5. The gas flow path sealing device according to claim 3, characterized in that: The first cavity (11) and the second cavity (12) have the same outer diameter as the first balancing cavity (7) and the second balancing cavity (9).

6. The gas flow path sealing device according to claim 5, characterized in that: The brush-type sealing structure (2) is provided with a baffle plate (13), which is located in the first cavity (11).

7. The gas flow path sealing device according to claim 6, characterized in that: The outer diameter surfaces of the comb-shaped sealing structure (1), the baffle plate (13), the brush-type sealing structure (2), the balance ring (6), the fingertip sealing structure (3), and the baffle plate (8) are fixedly connected by welding.

8. The gas flow path sealing device according to claim 1, characterized in that: A retaining ring (14) is provided on the side of the baffle (8) away from the fingertip sealing structure (3). The toothed sealing structure (1), the brush sealing structure (2) and the fingertip sealing structure (3) are secured to the stator mounting base (15) by the retaining ring (14).

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