Magnetic suspension sealing structure of air compressor impeller

Abstract

The invention discloses a magnetic suspension sealing structure of an air compressor impeller, and belongs to the technical field of air compressor impeller sealing, the magnetic suspension sealing structure comprises a static pressure sealing mechanism in an inner cavity formed by a rotating shaft and a back plate, the static pressure sealing mechanism comprises a main static pressure sealing block and two auxiliary static pressure sealing blocks, an annular cavity and a plurality of guide holes are formed in the main static pressure sealing block; a plurality of air holes are formed in the inner wall of the annular cavity at equal intervals in a surrounding mode, a first annular leakage-proof groove and a second annular leakage-proof groove are formed in the two sides of each air hole correspondingly, and a third annular leakage-proof groove and a guide channel are formed in the inner wall of each auxiliary static pressure sealing block. The double-state problem of'running floating 'and'shutdown falling' of a rotating shaft of a traditional magnetic suspension air compressor is avoided, meanwhile, the design thought that drainage is better than blockage is adopted, leakage of high-pressure gas is completely eradicated, and sealing reliability and running stability are enhanced.

Description

Technical Field

[0001] This invention relates to pneumatic components, specifically to the technical field of air compressor impeller seals, and more specifically to a magnetic levitation sealing structure for an air compressor impeller. Background Technology

[0002] As a highly efficient and energy-saving power equipment, the magnetic levitation air compressor achieves non-contact levitation support of the rotating shaft with magnetic levitation bearings. It has significant advantages such as low operating friction, low energy consumption, low vibration, and long service life. Its design concept is to eliminate the need for additional maintenance, which can greatly reduce the user's operation and maintenance costs. It has been widely used in many fields such as industrial production and energy supply.

[0003] The operating principle is as follows: In operation, the magnetic levitation bearing precisely controls the suspension of the shaft through electromagnetic force, so that there is no mechanical contact between the shaft and the bearing. In the shutdown state, the electromagnetic force disappears, the shaft loses its suspension support and falls radially to the mechanical limit position. That is, the shaft of the magnetic levitation air compressor is always in two completely different position states of "floating during operation" and "falling during shutdown" throughout its entire life cycle. The radial displacement of the shaft is relatively large (therefore, a large sealing gap is required to meet the radial displacement of the shaft). As a key component of the magnetic levitation air compressor, the core function of the sealing system is to prevent the high-pressure gas in the compression chamber from leaking to the low-pressure side or the outside, so as to ensure compression efficiency and operational stability. Therefore, the sealing structure must be adapted to the special motion state of the shaft.

[0004] While traditional floating ring seals and dry gas seals have proven applications in some ordinary compressors, both rely on the stability of the shaft's operating position and require regular maintenance. Floating ring seals depend on a stable fluid film between the shaft and the floating ring for sealing, while dry gas seals rely on an extremely thin, stable gas film. The significant radial displacement of the magnetic levitation air compressor shaft during its "floating-falling" motion directly disrupts the stability of these fluid or gas films, leading to seal failure. Furthermore, the associated lubrication and auxiliary air circuit systems require regular maintenance and replacement of spare parts, completely undermining the inherent maintenance-free advantage of magnetic levitation air compressors and increasing manufacturing and maintenance costs. Currently, the mainstream magnetic levitation air compressor uses labyrinth seals, which, while possessing certain advantages... The advantages of magnetic levitation air compressors include low cost, no maintenance, and compatibility with both floating and falling shaft states. However, due to structural design limitations (the need to satisfy the radial offset of the shaft, i.e., "floating-falling"), the sealing gap is usually large. This leads to a higher leakage of high-pressure gas, which seriously weakens the energy-saving effect of magnetic levitation air compressors. This is especially true for multi-stage compression magnetic levitation air compressors, which have higher exhaust pressures and require labyrinth seals in each compression unit. The leakage will have a cumulative effect, which has a more significant negative impact on the specific power (energy consumption per unit exhaust volume). In extreme cases, the specific power of a small-flow magnetic levitation air compressor may even be higher than that of a traditional screw air compressor, which greatly restricts the full realization of the energy-saving advantages of magnetic levitation air compressors. Summary of the Invention

[0005] This invention addresses the problem of overly simplistic solutions in existing technologies by providing a significantly different approach. The air compressor impeller seal, a pneumatic component, primarily offers a magnetic levitation sealing structure for the air compressor impeller. This solves the problem mentioned in the background section where existing air compressors require a large sealing gap (the gap between the main shaft and the sealing structure) to accommodate the shaft's "floating-falling" motion. However, this large gap can lead to excessive leakage of high-pressure gas.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: A magnetic levitation sealing structure for an air compressor impeller includes a static pressure sealing mechanism formed by a rotating shaft and a back plate within an inner cavity. The static pressure sealing mechanism is sleeved on the rotating shaft, forming a sealing gap between them. The rotating shaft presses the impeller body against one side of the back plate via a nut at its end. The sealing gap between the static pressure sealing mechanism and the rotating shaft is 10-20 micrometers in size. The static pressure sealing mechanism includes a main static pressure sealing block and two auxiliary static pressure sealing blocks, located at the two end faces of the main static pressure sealing block. An annular cavity is provided within the main static pressure sealing block. Multiple air holes are evenly spaced around the inner wall of the cavity, and the cross-sectional radius at the middle of the air hole is smaller than that at both ends. The air holes are connected to the sealing gap. A guide hole is provided in the middle of each air hole, and a guide component is provided in each guide hole. A first annular anti-leakage groove and a second annular anti-leakage groove are respectively provided on both sides of the air hole. A third annular anti-leakage groove is provided on the inner wall of each auxiliary static pressure sealing block. The third annular anti-leakage groove has the same number of guide channels as the guide holes, and the guide channels are evenly spaced around the cavity.

[0007] Preferably, the guide is a sealing assembly, which includes a cylinder with openings at both ends, the cylinder being embedded in a guide hole, a plug being provided inside the cylinder, and a return spring located on the plug, with one end of the plug protruding and engaging with a groove on the inner wall of the cylinder.

[0008] Preferably, the guide is a guide cylinder, and the interior of the guide cylinder is a hollow frustum structure, with the upper bottom surface of the frustum structure facing the air hole and the lower bottom surface of the frustum structure facing the third annular anti-leakage groove.

[0009] Preferably, an interface is provided on one side of the outer wall of the main static pressure sealing block, and the lower end of the interface is connected to the annular cavity.

[0010] Preferably, the interface is provided with a bellows for connecting to external high-pressure gas, and the upper end of the bellows passes through a circular hole on the back plate.

[0011] Preferably, the main static pressure sealing block and the two auxiliary static pressure sealing blocks are connected by bolts.

[0012] Preferably, the two end faces of the main static pressure sealing block are respectively provided with a first annular mounting groove and a second annular mounting groove. The radius of the second annular mounting groove is larger than that of the first annular mounting groove, and the second annular mounting groove and the first annular mounting groove are respectively located on the inner and outer sides of the corresponding guide hole. A first sealing ring is provided in the first annular mounting groove, and a second sealing ring is provided in the second annular mounting groove.

[0013] Preferably, one of the auxiliary static pressure sealing blocks has a third annular mounting groove on one side of its outer wall, and a third sealing ring is provided in each of the third annular mounting grooves, with the third sealing ring tightly fitting against one side of the inner wall of the back plate.

[0014] Preferably, the cross-sectional radii of the first annular leak-proof groove, the second annular leak-proof groove, and the third annular leak-proof groove gradually increase.

[0015] Preferably, the spacing between each pair of the first annular leak-proof groove, the second annular leak-proof groove, and the third annular leak-proof groove located on the same side is the same.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) By setting a main static pressure sealing block, a secondary static pressure sealing block, a first sealing ring, a second sealing ring, an annular cavity, a vent, a third sealing ring, an interface, and a bellows, the present invention achieves the introduction of high-pressure gas through the bellows and the formation of impact reaction force through the vent, so that the static pressure sealing mechanism is suspended above the rotating shaft. This allows a stable non-contact support state to be formed before the rotating shaft rotates, avoiding the dual-state problem of "floating up during operation" and "falling down when stopped" of the rotating shaft in traditional magnetic levitation air compressors. It does not need to rely on the stability of the rotating shaft position like floating ring seals and dry gas seals. At the same time, it eliminates the maintenance links such as the lubrication system of floating ring seals and the auxiliary air circuit maintenance of dry gas seals, continuing the inherent advantage of magnetic levitation air compressors that do not require maintenance, and greatly reducing the manufacturing and subsequent operation and maintenance costs of the machine body. Furthermore, the sealing gap is controlled within an extremely small range of 10-20 micrometers (breaking through the limitation of existing technologies that require a gap of more than 20 micrometers to adapt to the dual state of the rotating shaft). Compared with traditional labyrinth seals, this significantly reduces the leakage channel, substantially reduces the leakage of high-pressure gas, improves sealing performance, improves the specific power index of the equipment, and ensures the energy-saving advantages of the magnetic levitation air compressor. Moreover, the structure is simple in design and highly adaptable, which can stably ensure the sealing reliability during the operation of the rotating shaft, further improving the overall operational stability and service life of the equipment.

[0017] (2) The present invention achieves gradient leakage prevention by setting a main static pressure sealing block, annular cavity, air hole, guide hole, first annular leak-proof groove, second annular leak-proof groove, auxiliary static pressure sealing block, third annular leak-proof groove, guide channel, guide component, bellows, first sealing ring, second sealing ring and third sealing ring, by using three annular leak-proof grooves with gradually increasing size. The three-stage annular leak-proof grooves perform step-by-step throttling, effectively weakening the kinetic energy of the airflow leakage, achieving efficient initial leakage prevention, and greatly improving sealing performance and operational stability. Simultaneously, the airflow is guided to converge in an orderly manner in the third annular anti-leakage groove, laying the foundation for subsequent stable return flow. Adopting the design concept of "preferring to dredge rather than block", a closed-loop high-pressure gas return channel is constructed. Driven by the pressure difference in the return channel, the high-pressure gas can smoothly return to the annular cavity to form a stable cycle, solving the problem of high-pressure gas leakage in traditional sealing. Compared with the traditional "hard block" type seal, it not only has stronger sealing reliability, but also has less airflow resistance, which will not interfere with the normal rotation of the shaft and ensure smooth operation of the equipment. In addition, the guide components can be flexibly selected from either sealing components or guide cylinders to adapt to different working conditions: selecting sealing components can achieve unidirectional discharge of high-pressure gas in the initial stage, ensuring rapid and stable suspension of the static pressure sealing mechanism; selecting guide cylinders can make the return gas flow more smoothly after the mechanism is stably suspended, reducing the strength and stability requirements of the external high-pressure gas, and having greater energy-saving advantages. The overall design not only achieves efficient leak prevention, but also takes into account operational stability and flexibility in adapting to working conditions, providing a reliable guarantee for the efficient and energy-saving operation of the magnetic levitation air compressor.

[0018] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is an exploded view of the overall structure of the present invention; Figure 3 This is a schematic cross-sectional view of the overall structure of the present invention; Figure 4 This is a schematic diagram of the rotating shaft structure of the present invention; Figure 5 This is a schematic diagram of the static pressure sealing mechanism of the present invention; Figure 6 This is an exploded view of the static pressure sealing mechanism of the present invention; Figure 7 This is a schematic cross-sectional view of the main static pressure sealing block of the present invention; Figure 8 This is a schematic diagram of the axial cross-section of the main static pressure sealing block of the present invention; Figure 9 This is a schematic cross-sectional view of the auxiliary static pressure sealing block with a third annular mounting groove according to the present invention. Figure 10 This is a schematic diagram of the axial cross-section of the auxiliary static pressure sealing block of the present invention; Figure 11 This is a schematic cross-sectional view of the sealing component of the present invention; Figure 12 This is a schematic diagram of the cross-section of the guide cylinder of the present invention; Figure 13 This is a schematic diagram of the overall structure of the present invention with an axial cross-section. Figure 14 For the present invention Figure 13 Enlarged schematic diagram of area A (or high-pressure gas reflux direction); Figure 15 This is a schematic diagram of the external high-pressure gas pipeline connection of the present invention.

[0020] In the diagram: 1. Shaft; 2. Back plate; 3. Impeller body; 4. Static pressure sealing mechanism; 41. Main static pressure sealing block; 411. Annular cavity; 412. Air hole; 413. Guide hole; 414. First annular anti-leakage groove; 415. Second annular anti-leakage groove; 416. Interface; 417. First annular mounting groove; 418. Second annular mounting groove; 42. Secondary static pressure sealing block; 421. Third annular anti-leakage groove; 422. Guide channel; 423. Third annular mounting groove; 43. Sealing assembly; 431. Cylinder; 432. Plug; 433. Return spring; 434. Guide cylinder; 44. Bellows; 45. First sealing ring; 46. Second sealing ring; 47. Third sealing ring; 5. Air compressor body; 6. Air tank; 7. Small air compressor; 8. Solenoid valve. Detailed Implementation

[0021] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] Example 1, please refer to the appendix for details. Figure 1-15 As shown, a magnetic levitation sealing structure for an air compressor impeller includes a static pressure sealing mechanism 4 formed by a rotating shaft 1 and a back plate 2 within an inner cavity. The static pressure sealing mechanism 4 is sleeved on the rotating shaft 1, forming a sealing gap between them. The rotating shaft 1 presses the impeller body 3 against one side of the back plate 2 through a nut at its end. The characteristic feature is that the sealing gap between the static pressure sealing mechanism 4 and the rotating shaft 1 is 10-20 micrometers (in the prior art, if the rotating shaft 1 is to be in both floating and falling states, the sealing gap must be larger than 20 micrometers). The use of 10-20 micrometers is to reduce the sealing gap size, reduce air leakage, and at the same time provide a structural basis for the static pressure sealing mechanism 4 to be suspended on the rotating shaft 1. If the gap is too large, it will not be conducive to suspension. The static pressure sealing mechanism 4 includes a main static pressure sealing block 41 and two auxiliary static pressure sealing blocks 42. The two auxiliary static pressure sealing blocks 42 are located on the two end faces of the main static pressure sealing block 41. The main static pressure sealing block 41 has an annular cavity 411. Multiple air holes 412 are evenly spaced around the inner wall of the annular cavity 411, and the cross-sectional radius of the air hole 412 at the middle is smaller than that at both ends. The air holes 412 communicate with the sealing gap. A guide hole 413 is provided at the middle position of each air hole 412. The cross-sectional radius of the guide hole 413 is larger than that at the middle position of the air hole 412. A guide element is provided in each guide hole 413. A first annular anti-leakage groove 414 and a second annular anti-leakage groove 415 are respectively provided on both sides of the air hole 412. Each of the secondary static pressure sealing blocks 42 has a third annular anti-leakage groove 421 on its inner wall. The third annular anti-leakage groove 421 has the same number of guide channels 422 as the guide holes 413. The guide channels 422 are evenly spaced and distributed around the main static pressure sealing block 413. The cross-sectional diameter of the guide channel 422 is smaller than the cross-sectional diameter of the guide hole 413. This is so that after the main static pressure sealing block 41 and the secondary static pressure sealing block 42 are assembled, one end of the guide channel 422 presses on the guide member and positions the guide member in the guide hole 413. The sealing gap and the air hole 412, the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, the third annular anti-leakage groove 421, the guide channel 422 and the guide hole 413 on the same side constitute multiple axial return channels that surround the rotating shaft 1 and are evenly distributed around it.

[0025] Please refer to the appendix carefully. Figure 6-11As shown, the guide component is a sealing assembly 43, which includes a cylinder 431 with openings at both ends. The cylinder 431 is embedded in the guide hole 413. A plug 432 is provided inside the cylinder 431, and a return spring 433 is located on the plug 432. One end of the plug 432 protrudes and engages with a groove on the inner wall of the cylinder 431. Through the sealing assembly 43, in the initial state (that is, during the process of introducing high-pressure gas into the sealing gap so that the static pressure sealing mechanism 4 floats above the rotating shaft 1), the high-pressure gas can only enter through the vent 412. The gas flows into the sealing gap and then into the third annular anti-leakage groove 421. When the internal air pressure of the third annular anti-leakage groove 421 reaches a certain level, the return spring 433 can be compressed to push open the plug 432, allowing the high-pressure gas to flow back from the third annular anti-leakage groove 421 into the air hole 412. This ensures that during the initial period, the high-pressure gas is only unidirectionally discharged from the air hole 412 into the sealing gap, so that the rotating shaft 1 is subjected to uniform force. This allows the static pressure sealing mechanism 4 to be quickly and stably suspended above the rotating shaft 1. However, it requires high strength and stability of the external high-pressure gas. An interface 416 is provided on one side of the outer wall of the main static pressure sealing block 41, and the lower end of the interface 416 communicates with the annular cavity 411. A bellows 44 for receiving high-pressure gas is provided inside the interface 416, and the upper end of the bellows 44 passes through a circular hole on the back plate 2. Through the bellows 44, high-pressure gas is introduced into the annular cavity 411, and the static pressure sealing mechanism 4 is suspended above the rotating shaft 1, ensuring the stability of the connection. The main static pressure sealing block 41 and the two auxiliary static pressure sealing blocks 42 are connected by bolts, which facilitates assembly and disassembly. To facilitate the installation of the guide component within the guide hole 413, the two end faces of the main static pressure sealing block 41 are respectively provided with a first annular mounting groove 417 and a second annular mounting groove 418. The radius of the second annular mounting groove 418 is larger than that of the first annular mounting groove 417, and the second annular mounting groove 418 and the first annular mounting groove 417 are respectively located on the inner and outer sides of the corresponding guide hole 413. A first sealing ring 45 is provided in the first annular mounting groove 417, and a second sealing ring 46 is provided in the second annular mounting groove 418. The first sealing ring 45... The interaction between the second sealing ring 46 and the guide ring 46 prevents high-pressure gas from escaping at the connection point during the process of entering the guide hole 413 from the guide channel 422. One of the auxiliary static pressure sealing blocks 42 has a third annular mounting groove 423 on one side of its outer wall. A third sealing ring 47 is installed within the third annular mounting groove 423. The third sealing ring 47 fits tightly against one side of the inner wall of the back plate 2, improving the sealing performance at the connection point. Furthermore, the third sealing ring 47 itself has a certain degree of flexibility, ensuring a tight fit at the connection point while maintaining static pressure sealing. The entire structure 4 can move slightly (10-20 micrometers) to suspend on the rotating shaft 1. The cross-sectional radii of the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, and the third annular anti-leakage groove 421 gradually increase. The spacing between each pair of the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, and the third annular anti-leakage groove 421 on the same side is the same. The design of gradually increasing cross-sectional radii of the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, and the third annular anti-leakage groove 421 prevents the leakage of high-pressure gas.

[0026] Example 2, please refer to the appendix for details. Figure 6-10 and attached Figure 12As shown, the guide component is a guide cylinder 434, and the interior of the guide cylinder 434 is a hollow frustum structure. The upper bottom surface of the frustum structure faces the air hole 412, and the lower bottom surface of the frustum structure faces the third annular anti-leakage groove 421. Through the guide cylinder 434, in the initial state (that is, during the process of introducing high-pressure gas into the sealing gap so that the static pressure sealing mechanism 4 floats above the rotating shaft 1), most of the high-pressure gas will enter the sealing gap from the air hole 412 and then flow into the third annular anti-leakage groove 421. A small amount of high-pressure gas will directly enter the third annular anti-leakage groove 421 through the guide cylinder 434 and the guide channel 422. Therefore, in the initial stage, it will affect the uniformity of the reaction force of the static pressure sealing mechanism 4. However, after the static pressure sealing mechanism 4 is stably suspended on the rotating shaft 1, due to the absence of the reaction force of the return spring 433, the high-pressure gas will flow more stably in the return channel. Therefore, the stability and strength requirements of the external high-pressure gas are lower, and it is more energy-efficient.

[0027] Source and maintenance of external high-pressure gas: Since the static pressure sealing mechanism 4 of this invention requires external high-pressure gas to maintain the overall suspension state of the static pressure sealing mechanism 4 (suspended on the rotating shaft 1), the magnetic levitation air compressor cannot provide high-pressure gas when the air compressor body 5 is started. In order to enable the static pressure sealing mechanism 4 to operate normally, the following is provided: Figure 15 The maintenance system shown; Before starting the magnetic levitation air compressor, turn on the small air compressor 7 first, and the small air compressor 7 will supply air to the static pressure sealing mechanism. When the magnetic levitation air compressor has been running for a period of time, and the air tank 6 reaches a certain pressure, the air compressor body 5 supplies air to the static pressure sealing mechanism 4 through the air tank 6, and at this time the small air compressor 7 is turned off. When the magnetic levitation air compressor stops for a short time, the solenoid valve 8 between the air tank 6 and the air compressor body 5 is closed before the shutdown. After the complete shutdown, the solenoid valve 8 between the air tank 6 and the static pressure sealing mechanism 4 is closed. At this time, there is still pressure in the air tank 6, which can supply air to the static pressure sealing mechanism 4 on the next startup.

[0028] The specific operation is as follows: First, the external high-pressure gas is introduced into the annular cavity 411 of the main static pressure sealing block 41 through the bellows 44. Then, through the air holes 412 evenly distributed around the annular cavity 411, the high-pressure gas impacts the rotating shaft 1. The reaction force of the gas impact makes the static pressure sealing mechanism 4 float above the rotating shaft 1, so that the rotating shaft 1 forms a non-contact support between the rotating shafts 1, avoiding the two states of floating and falling that occur in the traditional structure. Gas flow direction (attached) Figure 14As shown): As high-pressure gas impacts the surface of the rotating shaft 1, two airflows with opposite directions are formed. These airflows then flow in opposite directions along the axial direction of the rotating shaft 1 within the sealing gap. For example, the high-pressure gas flowing towards the impeller body 3 will successively pass through the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, and the third annular anti-leakage groove on that side. Since the dimensions of the three annular anti-leakage grooves gradually increase, the cyclones formed within them become progressively larger and gradually converge into the third annular anti-leakage groove 421, thus playing a preliminary role in throttling and preventing leakage. Subsequently, the high-pressure gas in the third annular anti-leakage groove 421 flows back into the air hole 412 through the guide channel 422, the guide member, and the guide hole 413 (according to...). The Bernoulli effect (forming a backflow) prevents high-pressure gas from leaking out from both ends of the sealing gap. The same applies to the airflow in the other direction. In summary, the airflow in both directions forms multiple axial backflow channels that are equally spaced and distributed around the surface of the rotating shaft 1 (the backflow channel is composed of the sealing gap and the air hole 412, the first annular anti-leakage groove 414, the second annular anti-leakage groove 415, the third annular anti-leakage groove 421, the guide channel 422 and the guide hole 413 located on the same side). As the high-pressure gas is stably input into the bellows 44, the gas in the backflow channel will also form a stable circulation. With the idea of ​​"it is better to dredge than to block", the problem of high-pressure gas leakage is avoided. Then the rotating shaft 1 in the magnetic levitation air compressor can be driven to rotate.

[0029] The present invention has been described by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A magnetic suspension sealing structure of an air compressor impeller, comprising a static pressure sealing mechanism (4) in an inner cavity formed by a rotating shaft (1) and a back plate (2), the static pressure sealing mechanism (4) being sleeved on the rotating shaft (1) and forming a sealing gap therebetween, and the rotating shaft (1) pressing an impeller body (3) on one side of the back plate (2) through a nut at an end portion, characterized in that The sealing gap between the static pressure sealing mechanism (4) and the rotating shaft (1) is 10-20 micrometers. The static pressure sealing mechanism (4) includes a main static pressure sealing block (41) and two auxiliary static pressure sealing blocks (42). The two auxiliary static pressure sealing blocks (42) are located on the two end faces of the main static pressure sealing block (41). An annular cavity (411) is provided inside the main static pressure sealing block (41). Multiple air holes (412) are arranged at equal intervals around the inner wall of the annular cavity (411). The cross-sectional radius of the air holes (412) in the middle is smaller than that at both ends. The air holes (412) and The sealing gap is connected, and a guide hole (413) is provided in the middle of each of the air holes (412). A guide member is provided in each of the guide holes (413). A first annular anti-leakage groove (414) and a second annular anti-leakage groove (415) are provided on both sides of the air hole (412). A third annular anti-leakage groove (421) is provided on the inner wall of each of the auxiliary static pressure sealing blocks (42). The third annular anti-leakage groove (421) is provided with the same number of guide channels (422) as the guide holes (413), and the guide channels (422) are distributed around the perimeter at equal intervals.

2. The magnetic levitation seal structure of the air compressor impeller according to claim 1, characterized in that, The guide is a sealing assembly (43), which includes a cylinder (431) with openings at both ends. The cylinder (431) is embedded in a guide hole (413). A plug (432) is provided inside the cylinder (431), and a return spring (433) is located on the plug (432). One end of the plug (432) protrudes and engages with a groove on the inner wall of the cylinder (431).

3. The magnetic levitation seal structure of the air compressor impeller according to claim 1, characterized in that, The guide component is a guide cylinder (434), and the interior of the guide cylinder (434) is a hollow frustum structure. The upper bottom surface of the frustum structure faces the air hole (412), and the lower bottom surface of the frustum structure faces the third annular anti-leakage groove (421).

4. The magnetic levitation seal structure of a compressor impeller according to claim 1, characterized in that, The main static pressure sealing block (41) has an interface (416) on one side of its outer wall, and the lower end of the interface (416) is connected to the annular cavity (411).

5. The magnetic levitation sealing structure for an air compressor impeller according to claim 4, characterized in that, The interface (416) is provided with a bellows (44) for connecting to external high-pressure gas, and the upper end of the bellows (44) passes through the round hole on the back plate (2).

6. The magnetic levitation sealing structure for an air compressor impeller according to claim 4, characterized in that, The main static pressure sealing block (41) and the two auxiliary static pressure sealing blocks (42) are connected by bolts.

7. The magnetic levitation sealing structure for an air compressor impeller according to claim 6, characterized in that, The main static pressure sealing block (41) has a first annular mounting groove (417) and a second annular mounting groove (418) on its two end faces respectively. The radius of the second annular mounting groove (418) is larger than that of the first annular mounting groove (417). The second annular mounting groove (418) and the first annular mounting groove (417) are located on the inner and outer sides of the corresponding guide hole (413) respectively. A first sealing ring (45) is provided in the first annular mounting groove (417), and a second sealing ring (46) is provided in the second annular mounting groove (418).

8. The magnetic levitation sealing structure for an air compressor impeller according to claim 6, characterized in that, One of the auxiliary static pressure sealing blocks (42) has a third annular mounting groove (423) on one side of its outer wall. A third sealing ring (47) is provided in the third annular mounting groove (423), and the third sealing ring (47) is tightly fitted with one side of the inner wall of the back plate (2).

9. The magnetic levitation sealing structure for an air compressor impeller according to claim 1, characterized in that, The cross-sectional radii of the first annular anti-leakage groove (414), the second annular anti-leakage groove (415), and the third annular anti-leakage groove (421) gradually increase.

10. The magnetic levitation sealing structure for an air compressor impeller according to claim 9, characterized in that, The first annular anti-leakage groove (414), the second annular anti-leakage groove (415) and the third annular anti-leakage groove (421) located on the same side are spaced at the same distance.

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