Sealing structure of speed-increasing centrifugal air compressor

Abstract

The utility model relates to a kind of sealing structure of speed-increasing centrifugal air compressor, including the rotating shaft being equipped with sealing shoulder, the installation shell being located below sealing shoulder and being sleeved in rotating shaft outside, sealing ring is equipped in installation shell, the upper end surface of sealing ring is sealing surface and is contacted with sealing shoulder, sealing surface includes sealing surface outer ring, sealing surface inner ring being equipped in sealing surface outer ring inside, the upper end surface of sealing surface outer ring and sealing surface inner ring is equipped with sealing texture.Sealing texture of sealing surface outer ring is multiple T-shaped groove that is circumferentially distributed, the long side groove of T-shaped groove extends to the circumferential surface of sealing surface outer ring.Sealing texture of sealing surface inner ring is inverted rayleigh ladder groove.The utility model realizes stable sealing under rotation by sealing ring with sealing texture of sealing surface and sealing shoulder on rotating shaft, can be applied to high-speed rotating application occasion, ensure sealing under the condition of guaranteeing stability, meet the long-term stability requirement of speed-increasing centrifugal air compressor.

Description

Technical Field

[0001] This utility model relates to a sealing structure for a centrifugal air compressor with increased speed. Background Technology

[0002] In recent years, with economic development and societal progress, the demand for developing and using hydrogen fuel cell systems as a clean energy source has become increasingly strong. Air compressors are a crucial component in hydrogen fuel cell systems, their primary function being to provide the necessary and constant air pressure to the fuel system. Centrifugal air compressors offer advantages such as high speed, small size, and light weight. Speed-increasing centrifugal air compressors incorporate speed-increasing components within their overall structure, enabling the impeller to achieve higher speeds. This speed-increasing mechanism requires lubricating oil during operation to reduce friction and dissipate heat. To ensure continuous and stable operation of the equipment, suitable sealing elements are necessary to prevent oil leakage.

[0003] The conventional sealing solution involves machining a suitable seat hole on the housing corresponding to the rotating shaft, and then pressing in a lip seal ring with an interference fit. During rotation, the shaft generates a hydrodynamic film, which, under the influence of surface tension, prevents media leakage, achieving a dynamic seal. However, in centrifugal air compressors with speed-increasing mechanisms, the shaft speed may exceed the operating speed of the lip seal, leading to increased wear and premature hardening of the sealing lip. Contact mechanical seals also suffer from severe wear at high speeds, resulting in seal failure, while non-contact mechanical seals exhibit gaps that can cause leakage. Utility Model Content

[0004] This utility model addresses the problems existing in the prior art by providing a sealing structure for a centrifugal air compressor.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: a sealing structure for a centrifugal air compressor, including a rotating shaft with a sealing shoulder, an annular mounting housing sleeved on the outside of the rotating shaft and located below the sealing shoulder, a sealing ring being provided inside the mounting housing, the upper end surface of the sealing ring being a sealing surface and contacting the sealing shoulder, and the sealing surface being provided with sealing texture.

[0006] Furthermore, the sealing surface includes an outer sealing surface ring and an inner sealing surface ring disposed inside the outer sealing surface ring, and the upper end surfaces of both the outer sealing surface ring and the inner sealing surface ring are provided with sealing textures.

[0007] Furthermore, the sealing texture of the outer ring of the sealing surface consists of multiple T-shaped grooves evenly distributed around the circumference. The T-shaped grooves are arranged radially along the outer ring of the sealing surface, and the long side of the T-shaped grooves extends to the circumferential surface of the outer ring of the sealing surface.

[0008] Furthermore, the sealing texture of the inner ring of the sealing surface is an inverted Rayleigh stepped groove.

[0009] Furthermore, the mounting housing includes an annular inner wall, an annular outer wall, and an annular base plate disposed between the lower ends of the annular outer wall and the annular inner wall; the sealing ring is disposed between the annular outer wall and the annular inner wall.

[0010] Furthermore, an O-ring is provided between the inner circumferential side of the sealing ring and the inner wall of the ring.

[0011] Furthermore, a spring capable of vertical expansion and contraction is provided between the annular base plate and the lower end face of the sealing ring.

[0012] Furthermore, the inner circumferential side of the annular outer wall is evenly distributed with several limiting protrusions; the outer circumferential side of the sealing ring is evenly distributed with several limiting grooves, the positions of the limiting grooves and the limiting protrusions are corresponding, and the limiting protrusions extend into the limiting grooves to prevent the sealing ring from being rotated by the rotating shaft when it is started.

[0013] Furthermore, both the limiting protrusion and the limiting groove have rectangular cross-sections.

[0014] Furthermore, both the outer and inner rings of the sealing surface are provided with a notch on their peripheral sides, and the notch on the outer ring and the notch on the inner ring correspond to each other.

[0015] Compared with the prior art, the present invention has the following advantages: The present invention is reasonably designed and uses a sealing ring with sealing texture on the sealing surface and a sealing shoulder on the rotating shaft to achieve stable sealing under rotation. It can be applied to high-speed rotating applications, ensuring sealing performance while maintaining stability, and meeting the long-term stability requirements of speed-up centrifugal air compressors. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the front cross-sectional structure of an embodiment of the present utility model; Figure 2 Figure 1 A magnified view of a portion of the image; Figure 3 This is a three-dimensional structural diagram of the mounting housing in an embodiment of this utility model; Figure 4 This is a schematic diagram of the surface texture of the sealing ring in an embodiment of this utility model. Figure 1 ; Figure 5 This is a schematic diagram of the surface texture of the sealing ring in an embodiment of this utility model. Figure 2 ; Figure 6 yes Figure 4 Enlarged diagram of point A in the diagram.

[0017] In the picture: 1-Mounting housing; 2-Spring; 3-Sealing ring; 4-O-ring; 5-Rotating shaft; 6-Sealing surface outer ring; 7-Sealing surface inner ring; 8-T-slot; 9-Inverted Rayleigh step groove; 10-Limiting groove; 11-Limiting protrusion; 12-Annular inner wall; 13-Annular outer wall; 14-Annular base plate; 15-Sealing shoulder; 16-Notch; 17-Sealing surface. Detailed Implementation

[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 this utility model.

[0020] like Figures 1-6 As shown, the present invention discloses a sealing structure for a centrifugal air compressor, comprising a rotating shaft 5 with a sealing shoulder 15 on its outer surface, and an annular mounting housing 1 sleeved on the outside of the rotating shaft 5 and located below the sealing shoulder 15. A sealing ring 3 is provided inside the mounting housing 1, and the upper end face of the sealing ring 3 is a sealing surface 17 that contacts the end face of the sealing shoulder 15. The sealing surface is provided with a sealing texture.

[0021] In this embodiment, the sealing surface includes an outer sealing ring 6 and an inner sealing ring 7 coaxially disposed inside the outer sealing ring 6. Both the outer sealing ring 6 and the inner sealing ring 7 have sealing textures on their upper surfaces. Furthermore, both the outer and inner sealing rings have a notch 16 on their peripheral sides, with the notch in the outer sealing ring 6 and the notch in the inner sealing ring 7 corresponding in position.

[0022] In this embodiment, the sealing texture of the outer ring 6 of the sealing surface is a plurality of T-shaped grooves 8 evenly distributed in a circle. The T-shaped grooves 8 are arranged radially along the outer ring 6 of the sealing surface. The T-shaped grooves 8 are composed of short side grooves and long side grooves that are perpendicular to each other. The long side grooves of the T-shaped grooves 8 extend to the peripheral side surface of the outer ring 6 of the sealing surface.

[0023] In this embodiment, the sealing texture of the inner ring 7 of the sealing surface is an inverted Rayleigh stepped groove 9.

[0024] In this embodiment, the rotating shaft 5 rotates counterclockwise when viewed from the front of the sealing surface with the sealing texture. When the rotating shaft 5 rotates counterclockwise, the T-groove 8 of the outer ring 6 of the sealing surface generates a hydrodynamic pressure effect. The resulting positive pressure forms a film between the two contact surfaces, thus providing a non-contact seal and reducing friction. Simultaneously, the inverted Rayleigh stepped groove 9 of the inner ring 7 of the sealing surface continuously discharges sealing medium during rotation, creating a negative pressure. This negative pressure draws the leaked sealing medium back to the original medium side, reducing the leakage. The cooperation of the two rings reduces both friction and leakage.

[0025] In this embodiment, the mounting housing 1 includes a coaxially arranged annular inner wall 12, an annular outer wall 13, and an annular base plate 14 disposed between the lower ends of the annular outer wall 13 and the annular inner wall 12. That is, the upper end of the mounting housing is open, and the lower end is a closed structure. The rotation shaft passes through the inner side of the annular inner wall. The sealing ring 3 is disposed between the annular outer wall 13 and the annular inner wall 12, and the upper end of the sealing ring extends out of the upper opening of the mounting housing.

[0026] In this embodiment, an O-ring 4 is provided between the inner circumferential side of the sealing ring 3 and the annular inner wall 12. The main function of the O-ring is to prevent the sealing medium from leaking through the sealing surface.

[0027] In this embodiment, a spring 2 that can vertically expand and contract is provided between the annular base plate 14 and the lower end face of the sealing ring 3. The spring 2 is sleeved on the outer side of the annular inner wall 12, with the lower end of the spring 2 in contact with the annular base plate 14 and the upper end of the spring 2 in contact with the lower end face of the sealing ring 3. During operation, the equipment inevitably vibrates due to temperature changes and other reasons, which causes the position of the rotating shaft to be not absolutely fixed. The function of the spring is to absorb and compensate for this axial displacement and vibration.

[0028] In this embodiment, three limiting protrusions 11 are evenly distributed around the inner circumference of the annular outer wall 13. The limiting protrusions 11 are elongated and extend axially along the annular outer wall 13. Three limiting grooves 10 are evenly distributed around the outer circumference of the sealing ring 3. The limiting grooves 10 extend axially through the sealing ring 3, and their positions correspond to the three limiting protrusions 11. When the sealing ring 3 is installed inside the mounting housing 1, the limiting protrusions 11 extend into the limiting grooves 10. The function of the limiting protrusions and limiting grooves is to prevent the sealing ring from rotating due to the rotating shaft during startup.

[0029] In this embodiment, both the limiting protrusion 11 and the limiting groove 10 have rectangular cross-sections. Preferably, both sides of the limiting protrusion 11 and the limiting groove 10 have rounded corners.

[0030] In this embodiment, the sealing shoulder of the rotating shaft 5 contacts the sealing surface of the sealing ring 3, and the rotating shaft 5 body is fixed in place by other structures of the air compressor to prevent movement.

[0031] This sealing structure forms two seals through the sealing surface of the sealing ring and the O-ring, thereby increasing the speed of the impeller shaft, ensuring a tight fit and proper installation between the impeller shaft and the mechanical seal, and enabling stable installation and operation of the mechanical seal. This is beneficial for the stable operation of the impeller shaft under high-speed rotation conditions. The overall structure is stable and reliable, and can be applied to high-speed rotation applications.

[0032] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0033] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this utility model above include states or shapes that are similar to, close to, or approximate with them.

[0034] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A sealing structure for a speed-increasing centrifugal air compressor, characterized in that: The device includes a rotating shaft with a sealing shoulder, and an annular mounting housing fitted outside the rotating shaft and located below the sealing shoulder. A sealing ring is provided inside the mounting housing. The upper end face of the sealing ring is a sealing surface and contacts the sealing shoulder. The sealing surface is provided with a sealing texture.

2. The sealing structure for a centrifugal air compressor according to claim 1, characterized in that: The sealing surface includes an outer sealing surface ring and an inner sealing surface ring disposed inside the outer sealing surface ring. Both the upper end surfaces of the outer sealing surface ring and the inner sealing surface ring are provided with sealing textures.

3. The sealing structure for a speed-increasing centrifugal air compressor according to claim 2, characterized in that: The sealing texture of the outer ring of the sealing surface consists of multiple T-shaped grooves evenly distributed around the circumference. The T-shaped grooves are arranged radially along the outer ring of the sealing surface, and the long side of the T-shaped grooves extends to the circumferential surface of the outer ring of the sealing surface.

4. The sealing structure for a speed-increasing centrifugal air compressor according to claim 2, characterized in that: The sealing texture of the inner ring of the sealing surface is an inverted Rayleigh stepped groove.

5. The sealing structure for a speed-increasing centrifugal air compressor according to claim 1, characterized in that: The mounting housing includes an annular inner wall, an annular outer wall, and an annular base plate disposed between the lower ends of the annular outer wall and the annular inner wall; the sealing ring is disposed between the annular outer wall and the annular inner wall.

6. The sealing structure for a speed-increasing centrifugal air compressor according to claim 5, characterized in that: An O-ring is provided between the inner circumferential side of the sealing ring and the inner wall of the ring.

7. The sealing structure for a speed-increasing centrifugal air compressor according to claim 5, characterized in that: A spring capable of vertical expansion and contraction is provided between the annular base plate and the lower end face of the sealing ring.

8. The sealing structure for a speed-increasing centrifugal air compressor according to claim 5, characterized in that: The inner circumference of the outer annular wall has a number of limiting protrusions evenly distributed around its circumference; the outer circumference of the sealing ring has a number of limiting grooves evenly distributed around its circumference, the limiting grooves corresponding to the positions of the limiting protrusions, the limiting protrusions extending into the limiting grooves to prevent the sealing ring from being rotated by the rotating shaft when it is started.

9. The sealing structure for a speed-increasing centrifugal air compressor according to claim 8, characterized in that: Both the limiting protrusion and the limiting groove have rectangular cross-sections.

10. A sealing structure for a centrifugal air compressor according to claim 2, characterized in that: Both the outer and inner rings of the sealing surface have a notch on their circumference, and the notch on the outer ring and the notch on the inner ring correspond to each other.

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