Follow-up micro-nano magnetic medium sealing device

Abstract

The invention provides a follow-up micro-nano magnetic medium sealing device, and relates to the technical field of sealing devices.The follow-up micro-nano magnetic medium sealing device comprises a shell, a rotating shaft, a floating sealing seat and a first sealing assembly; the rotating shaft, the first sealing assembly and the floating sealing seat are sequentially arranged in a sleeving mode from inside to outside, the floating sealing seat and the first sealing assembly are both matched with the cavity and movably connected with the cavity in the radial direction of the rotating shaft, the first sealing assembly comprises a first pole shoe, a first permanent magnet and a second pole shoe, and the magnetic pole direction of the first permanent magnet is consistent with the axial direction of the rotating shaft; a first gap is defined between the inner circumferential surface of each of the first pole shoe and the second pole shoe and the outer circumferential surface of the rotating shaft, a micro-nano magnetic medium is adsorbed in the first gap, and a second gap communicated with the outside is defined between the outer circumferential surface of the floating sealing seat and the inner circumferential surface of the cavity. The sealing assembly can run out in the radial direction along with the rotating shaft under the action of the hydrodynamic effect, so that the gap between the sealing assembly and the rotating shaft is changed, and the influence of radial run-out of the rotating shaft is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sealing devices, and in particular to a follow-up type micro-nano magnetic medium sealing device. Background Art

[0002] Micro-nano magnetic medium seals use magnetic fields to control micro-nano magnetic medium to form a continuous and stable liquid sealing ring in the sealing gap to achieve non-contact sealing. Therefore, micro-nano magnetic medium seals have the characteristic of "zero leakage", but radial vibration of the rotating shaft will cause the pressure resistance and service life of the micro-nano magnetic medium seal to decrease, and even cause friction and damage between the micro-nano magnetic medium seal pole teeth and the rotating shaft.

[0003] In order to reduce the influence of the radial runout of the rotating shaft on the sealing performance of the micro-nano magnetic medium, a floating micro-nano magnetic medium sealing structure is adopted in the related technology, which specifically includes the following two types:

[0004] 1. A magnetic floating ring is set between the housing and the rotating shaft, and a micro-nano magnetic medium is continuously circulated from the outside to form a liquid film between the magnetic floating ring and the rotating shaft, thereby sealing the leaked gas. However, in this method, the micro-nano magnetic medium is difficult to maintain its distribution state due to gravity, and the continuous external supply of micro-nano magnetic medium also increases the cost;

[0005] 2. A floating ring is set between the housing and the rotating shaft, and multiple springs are installed circumferentially between the floating ring and the housing to offset the eccentric force. However, the spring can easily reduce the reliability of the sealing device, and the structure is complex. It is difficult to ensure coaxiality during processing, and it is also easy to affect the sealing performance and life. Summary of the invention

[0006] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0007] To this end, an embodiment of the present invention proposes a follow-up micro-nano magnetic medium sealing device, which can make the sealing component radially jump with the rotating shaft under the action of the fluid dynamic pressure effect, so as to change the gap between the sealing component and the rotating shaft, reduce the influence of the radial jump of the rotating shaft, and improve the pressure resistance and service life.

[0008] According to an embodiment of the present invention, a follow-up micro-nano magnetic medium sealing device includes a shell, a rotating shaft, a floating seal seat and a first sealing component, wherein the shell has a chamber, the rotating shaft is pivotally connected to the chamber and at least one end is located outside the shell; the rotating shaft, the first sealing component and the floating seal seat are sequentially sleeved from the inside to the outside, the floating seal seat and the first sealing component are both matched with the chamber and movably connected to the chamber along the radial direction of the rotating shaft, the first sealing component includes a first pole shoe, a first permanent magnet and a second pole shoe arranged in sequence along the axial direction of the rotating shaft, the magnetic pole direction of the first permanent magnet is consistent with the axial direction of the rotating shaft; a first gap is defined between the inner circumference of each of the first pole shoe and the second pole shoe and the outer circumference of the rotating shaft, the first gap has micro-nano magnetic medium adsorbed in it, and a second gap connected to the outside is defined between the outer circumference of the floating seal seat and the inner circumference of the chamber.

[0009] According to the follow-up micro-nano magnetic medium sealing device of the embodiment of the present invention, a floating sealing structure is formed by the cooperation of a floating sealing seat and a first sealing component. Since the floating sealing structure is movably connected to the chamber along the radial direction of the rotating shaft, when the rotating shaft is in a radially beating state, that is, when the rotating shaft is eccentric relative to the first pole shoe and the second pole shoe, the first gap will be uneven in the circumferential direction, and there will be large gaps and small gaps in the circumferential direction. When the sealing device is installed on the sealed device, the high-pressure gas in the sealed device will enter the first gap. At this time, the fluid dynamic pressure effect generated by the high-pressure gas will make the small gap side pressure in the first gap very large, and with the first gap side pressure, the pressure on the small gap side will be very large. The low pressure in the two gaps forms a pressure difference. Under the action of the pressure difference, the first pole shoe and the second pole shoe are pushed to the side of the small gap, that is, the first pole shoe and the second pole shoe move in the direction of increasing the small gap side, so as to realize the following movement of the first pole shoe and the second pole shoe relative to the rotating shaft, thereby adaptively adjusting the concentricity between the rotating shaft and the first pole shoe and the second pole shoe, and reducing the influence of the radial runout of the rotating shaft on the sealing of the micro-nano magnetic medium. Compared with the related technology, the present invention can make the sealing component radially run out with the rotating shaft under the action of the fluid dynamic pressure effect, so as to change the gap between the sealing component and the rotating shaft, reduce the influence of the radial runout of the rotating shaft, and improve the pressure resistance and service life.

[0010] In some embodiments, each of the first pole shoe and the second pole shoe is provided with a first pole tooth, and the first pole teeth are multiple and arranged at intervals along the axial direction of the rotating shaft, and the first gap is defined between all the first pole teeth and the outer peripheral surface of the rotating shaft.

[0011] Furthermore, the first gap is smaller than the second gap.

[0012] Furthermore, a first sealing ring is sandwiched between the outer circumferential surface of at least one of the first pole shoe and the second pole shoe and the inner circumferential surface of the floating sealing seat.

[0013] In some embodiments, the sealing device also includes a first end cover and a magnetic ring, the first end cover and the magnetic ring are both sleeved on the rotating shaft and are arranged on both sides of the first sealing assembly along the axial direction of the rotating shaft, the first end cover is connected to the floating sealing seat, the end surface of the first pole shoe facing away from the first permanent magnet abuts against the first end cover, the inner circumferential surface of the floating sealing seat is provided with a first annular boss, and the magnetic ring is located between the second pole shoe and the first annular boss and abuts against the first annular boss.

[0014] In some embodiments, the sealing device also includes a first magnetic isolation ring, which is sleeved on the rotating shaft and located in the inner cavity of the floating sealing seat, and the two end surfaces of the first magnetic isolation ring along the axial direction of the rotating shaft are respectively abutted against the second pole shoe and the magnetic conductive ring.

[0015] In some embodiments, the sealing device also includes a second sealing component, which is matched with the chamber and is sleeved on the rotating shaft. The second sealing component and the first sealing component are arranged along the axial direction of the rotating shaft and are closer to the high-pressure side than the first sealing component, so that the first sealing component is separated from the high-pressure side by the second sealing component.

[0016] In some embodiments, the second sealing assembly and the second pole shoe are disposed on both sides of the magnetic conductive ring along the axial direction of the rotating shaft, and the floating sealing seat and the magnetic conductive ring are both movably connected to the second sealing assembly along the radial direction of the rotating shaft;

[0017] The second sealing assembly includes a third pole shoe, a second permanent magnet and a fourth pole shoe which are sequentially sleeved from the inside to the outside, each of the third pole shoe and the fourth pole shoe is provided with a second pole tooth adjacent to the end face of the magnetic conductive ring, a micro-nano magnetic medium is adsorbed between the second pole tooth and the magnetic conductive ring, and the magnetic pole direction of the second permanent magnet is perpendicular to the axial direction of the rotating shaft.

[0018] Further, the magnetic pole of the first permanent magnet adjacent to the second pole shoe is the same as the magnetic pole of the second permanent magnet adjacent to the fourth pole shoe.

[0019] Furthermore, a second sealing ring is sandwiched between the outer circumferential surface of the fourth pole shoe and the inner circumferential surface of the chamber.

[0020] In some embodiments, the end surface of the magnetic conductive ring adjacent to the second sealing assembly is provided with a boss, the boss is spaced apart from the first annular shoulder in the radial direction of the rotating shaft, and the second pole tooth is located between the boss and the first annular shoulder;

[0021] There are multiple second pole teeth and they are arranged at intervals along the radial direction of the rotating shaft. A third gap is defined between the second pole tooth closest to the boss and the boss. A fourth gap is defined between the second pole tooth closest to the first annular shoulder and the first annular shoulder. Both the third gap and the fourth gap are larger than the first gap.

[0022] In some embodiments, the sealing device also includes a labyrinth sealing ring, an air flow channel for accommodating the labyrinth sealing ring is defined between the inner circumference of the third pole shoe and the outer circumference of the rotating shaft, the labyrinth sealing ring is sleeved on the rotating shaft and connected to the third pole shoe, the inner circumference of the labyrinth sealing ring is provided with sealing teeth, a fifth gap is defined between the sealing teeth and the outer circumference of the rotating shaft, a sixth gap is defined between the inner circumference of the magnetic ring and the outer circumference of the rotating shaft, and the fifth gap is smaller than the sixth gap.

[0023] Furthermore, there are a plurality of sealing teeth which are arranged at intervals along the axial direction of the rotating shaft.

[0024] Furthermore, the sealing teeth are saw teeth, wherein the sealing teeth closest to the magnetic conductive ring are inclined in the direction from the second pole shoe toward the first pole shoe, and the remaining sealing teeth are inclined in the direction from the first pole shoe toward the second pole shoe.

[0025] In some embodiments, the sealing device further comprises a second end cover, wherein the second end cover is sleeved on the rotating shaft and connected to the outer shell, and the second end cover is suitable for sealing the chamber.

[0026] In some embodiments, the sealing device also includes a second magnetic isolation ring, which is matched with the chamber and sleeved on the rotating shaft. The second magnetic isolation ring is located between the second end cover and the floating seal seat, and the end surface of the second magnetic isolation ring facing away from the floating seal seat abuts against the second end cover.

[0027] In some embodiments, the floating seal seat has a first end face and a second end face that are opposite to each other along the axial direction of the rotating shaft, and a ball retainer is provided on the outer periphery of each of the first end face and the second end face of the floating seal seat, and the ball retainer and the floating seal seat form an annular groove;

[0028] A ball is arranged in the annular groove, at least part of which protrudes out of the annular groove along the axial direction of the rotating shaft and is in rolling contact with the second magnetic isolation ring or the fourth pole shoe, so as to facilitate the radial movement of the floating seal seat relative to the chamber along the rotating shaft.

[0029] Furthermore, there are a plurality of balls arranged along the circumference of the annular groove, and any two adjacent balls are in rolling contact.

[0030] In some embodiments, the sealing device further comprises a first bearing and a second bearing, wherein the first bearing and the second bearing are both matched with the chamber and sleeved on the rotating shaft, and each of the first bearing and the second bearing is closer to the high-pressure side than the second sealing assembly;

[0031] The rotating shaft is provided with a shoulder, and the inner circumferential surface of the outer shell is provided with a second annular boss. The two opposite end surfaces of the shoulder along the axial direction of the rotating shaft are respectively abutted against the first bearing and the second bearing. The end surface of the first bearing facing away from the shoulder is abutted against the fourth pole shoe through a third magnetic isolation ring. The third magnetic isolation ring is matched with the chamber and is sleeved on the rotating shaft. The end surface of the second bearing facing away from the shoulder is abutted against the second annular boss.

[0032] In some embodiments, the housing is suitable for being connected to a sealed device and is provided with a third sealing ring, wherein the third sealing ring is sandwiched between the housing and the sealed device.

[0033] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the structure of a follow-up micro-nano magnetic medium sealing device according to an embodiment of the present invention.

[0035] Figure 2 yes Figure 1 Schematic diagram of the local enlarged structure at point A in the middle.

[0036] Figure 3 yes Figure 1 Schematic diagram of the local enlarged structure at point B in the middle.

[0037] Figure 4 yes Figure 1 Schematic diagram of the local enlarged structure at point C in the middle.

[0038] Figure 5 It is a schematic diagram of the air flow force on the floating sealing structure of the follow-up micro-nano magnetic medium sealing device according to an embodiment of the present invention when the shaft is in radial runout state.

[0039] Reference numerals:

[0040] 1. housing; 11. chamber; 12. second end cover; 13. second magnetic isolation ring; 14. first bearing; 15. second bearing; 16. second annular boss; 17. third magnetic isolation ring; 18. third sealing ring;

[0041] 2. Rotating shaft; 21. First gap; 22. Shaft shoulder;

[0042] 3. Floating seal seat; 31. Second gap; 32. First annular shoulder; 33. Ball cage; 34. Ball;

[0043] 4. first sealing assembly; 41. first pole shoe; 42. first permanent magnet; 43. second pole shoe; 44. first pole tooth; 45. first sealing ring;

[0044] 5. First end cover;

[0045] 6. magnetic conductive ring; 61. boss; 62. sixth gap;

[0046] 7. The first magnetic isolation ring;

[0047] 8. second sealing assembly; 81. third pole shoe; 82. second permanent magnet; 83. fourth pole shoe; 84. second pole tooth; 85. second sealing ring; 86. third gap; 87. fourth gap;

[0048] 9. labyrinth sealing ring; 91. sealing teeth; 92. fifth gap. DETAILED DESCRIPTION

[0049] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0050] like Figures 1 to 5 As shown, a follow-up micro-nano magnetic medium sealing device according to an embodiment of the present invention comprises a housing 1, a rotating shaft 2, a floating sealing seat 3 and a first sealing component 4, wherein the housing 1 has a chamber 11, the rotating shaft 2 is pivotally connected to the chamber 11 and at least one end is located outside the housing 1; the rotating shaft 2, the first sealing component 4 and the floating sealing seat 3 are sequentially sleeved from the inside to the outside, the floating sealing seat 3 and the first sealing component 4 are both matched with the chamber 11 and are movably connected to the chamber 11 along the radial direction of the rotating shaft 2, and the first sealing component 4 comprises a first pole shoe 41, a first Permanent magnet 42 and second pole shoe 43, the magnetic pole direction of the first permanent magnet 42 is consistent with the axial direction of the rotating shaft 2; the inner circumference of each of the first pole shoe 41 and the second pole shoe 43 defines a first gap 21 with the outer circumference of the rotating shaft 2, and the first gap 21 is adsorbed with micro-nano magnetic medium; the outer circumference of the floating seal seat 3 and the inner circumference of the chamber 11 define a second gap 31 connected to the outside, and the pressure of the first gap 21 is higher than the pressure of the second gap 31, so that the floating seal seat 3 and the first sealing assembly 4 can adjust the radial position relative to the chamber 11 with the rotating shaft 2 under the action of the pressure difference.

[0051] According to the follow-up micro-nano magnetic medium sealing device of the embodiment of the present invention, a floating sealing structure is formed by the cooperation of a floating sealing seat 3 and a first sealing component 4. Since the floating sealing structure is movably connected to the chamber 11 along the radial direction of the rotating shaft 2, and the first gap 21 is smaller than the second gap 31, the pressure of the first gap 21 is higher than the pressure of the second gap 31. Therefore, when the rotating shaft 2 is in a radial beating state, that is, when the rotating shaft 2 is eccentric relative to the first pole shoe 41 and the second pole shoe 43, the first gap 21 will be uneven in the circumferential direction, and there will be large gaps and small gaps in the circumferential direction. When the sealing device is installed on the sealed device, the high-pressure gas in the sealed device will enter the first gap 21. At this time, the fluid dynamic pressure effect generated by the high-pressure gas will cause the small gap in the first gap 21 to The pressure on the gap side is very large, and forms a pressure difference with the low pressure of the second gap 31. Under the action of the pressure difference, the first pole shoe 41 and the second pole shoe 43 are pushed to the small gap side, that is, the first pole shoe 41 and the second pole shoe 43 move in the direction of increasing the small gap side, so as to realize the following movement of the first pole shoe 41 and the second pole shoe 43 relative to the rotating shaft 2, thereby adaptively adjusting the concentricity between the rotating shaft 2 and the first pole shoe 41 and the second pole shoe 43, and reducing the influence of the radial runout of the rotating shaft 2 on the sealing of the micro-nano magnetic medium. Compared with the related art, the present invention can make the sealing component (that is, the first sealing component 4) radially run out with the rotating shaft 2 under the action of the fluid dynamic pressure effect, so as to change the gap between the sealing component and the rotating shaft 2, reduce the influence of the radial runout of the rotating shaft 2, and improve the pressure resistance and service life.

[0052] Specifically, the chamber 11 may extend along the axial direction of the rotating shaft 2. The axial direction of the rotating shaft 2 may be the left-right direction in the figure. The rotating shaft 2, the first sealing assembly 4 and the floating sealing seat 3 may be arranged coaxially. The first pole shoe 41 and the second pole shoe 43 may have the same structure and specifications. The first permanent magnet 42 may be an annular permanent magnet. The magnetic pole direction of the first permanent magnet 42 is consistent with the axial direction of the rotating shaft 2, that is, the N pole and the S pole of the first permanent magnet 42 are arranged along the left-right direction in the figure. Taking the figure as an example, the first pole shoe 41 is located on the left side of the second pole shoe 43.

[0053] It can be understood that the first sealing component 4 forms an axial micro-nano magnetic medium seal in the sealing device. The "inner circumference of the chamber 11" is the inner circumference of the housing 1 used to surround the chamber 11. The magnetic circuit of the first sealing component 4 is: the magnetic field emitted from the N pole of the first permanent magnet 42 passes through the first pole shoe 41, the rotating shaft 2 and the second pole shoe 43 and returns to the S pole of the first permanent magnet 42.

[0054] The second gap 31 is connected to the outside world, so that the low-pressure gas outside the housing 1 can enter the second gap 31. Therefore, after the high-pressure gas in the sealed device enters the first gap 21, the pressure difference formed by the low pressure of the gas in the second gap 31 and the fluid dynamic pressure generated by the high-pressure gas in the first gap 21 can be used to stabilize the floating seal structure in the chamber 11. While ensuring the sealing performance, the floating seal structure can be actively aligned with the radial jump of the rotating shaft 2, so that the sealing device can adaptively adjust the concentricity between the floating seal structure and the rotating shaft 2. Therefore, compared with the related art, the present invention can ensure the sealing performance based on the existing conditions of the sealing device, the micro-nano magnetic medium has a good distribution state, low cost, simple overall structure and high reliability.

[0055] It should be noted that after the sealing device is installed on the sealed equipment, high-pressure gas needs to be filled into the sealed chamber of the sealed equipment before starting. Therefore, in the sealing device, a high-pressure side and a low-pressure side will be formed outside the shell 1, wherein the high-pressure gas on the high-pressure side will enter the first gap 21, and the low-pressure gas on the low-pressure side (it can also be said to be the outside atmosphere) can enter the second gap 31.

[0056] At this time, the fluid dynamic pressure effect generated by the high-pressure gas in the first gap 21 generates a force on the floating seal structure toward the outer peripheral surface of the first sealing component 4, while the gas pressure in the second gap 31 generates a force on the floating seal structure toward the inner peripheral surface of the first sealing component 4. However, since the former is the fluid dynamic pressure effect generated by high-pressure gas and the latter is low-pressure gas, the force generated by the former is much larger, so the overall resultant force is outward. Therefore, when the radial runout of the rotating shaft 2 causes a small gap side in the circumferential direction of the first gap 21, the first pole shoe 41 and the second pole shoe 43 will move in the direction of increasing the small gap side of the first gap 21, so as to adjust the concentricity of the floating seal structure relative to the rotating shaft 2 and improve the pressure resistance of the sealing device.

[0057] In addition, the present invention is not limited to application in, for example, a nuclear reactor main pump, but can also be applied to other sealing occasions where radial runout of the rotating shaft 2 exists.

[0058] Figure 5 Wherein O is the geometric center of the floating seal structure, O' is the geometric center of the shaft 2, ω is the rotational angular velocity of the shaft 2, p is the airflow pressure distribution in the gap between the floating seal structure and the shaft 2, and F is the airflow force on the floating seal structure.

[0059] Furthermore, the first pole shoe 41 and the second pole shoe 43 may be mirror-symmetrical with respect to a reference plane, the reference plane is perpendicular to the axial direction of the rotating shaft 2, and the center of the first permanent magnet 42 is coplanar with the reference plane, that is, the first permanent magnet 42 is mirror-symmetrical with respect to the reference plane.

[0060] like Figure 1As shown, in some embodiments, each of the first pole shoe 41 and the second pole shoe 43 is provided with a first pole tooth 44, and there are multiple first pole teeth 44 and they are arranged at intervals along the axial direction of the rotating shaft 2, and a first gap 21 is defined between all the first pole teeth 44 and the outer peripheral surface of the rotating shaft 2, wherein the multiple first pole teeth 44 are preferably arranged at equal intervals along the axial direction of the rotating shaft 2 to ensure uniform force on all the pole teeth in the first pole shoe 41 and the second pole shoe 43.

[0061] Furthermore, the first gap 21 is smaller than the second gap 31. In other words, the maximum distance from the inner circumference of each of the first pole shoe 41 and the second pole shoe 43 to the outer circumference of the rotating shaft 2 is smaller than the minimum distance from the outer circumference of the floating seal seat 3 to the inner circumference of the chamber 11. That is to say, the first gap 21 is smaller than the second gap 31 everywhere in the circumferential direction of the rotating shaft 2.

[0062] Furthermore, a first sealing ring 45 is sandwiched between the outer circumference of each of the first pole shoe 41 and the second pole shoe 43 and the inner circumference of the floating seal seat 3 to further ensure the sealing performance.

[0063] For example, taking the figure as an example, the outer circumference of the first pole shoe 41 and the outer circumference of the second pole shoe 43 can be provided with annular grooves, and the first sealing ring 45 can be fitted in the annular grooves and abut against the inner circumference of the floating sealing seat 3.

[0064] like Figure 1 As shown, in some embodiments, the sealing device also includes a first end cover 5 and a magnetic ring 6, which are both sleeved on the rotating shaft 2 and are arranged on both sides of the first sealing component 4 along the axial direction of the rotating shaft 2, the first end cover 5 is connected to the floating seal seat 3, the end face of the first pole shoe 41 facing away from the first permanent magnet 42 abuts against the first end cover 5, the inner circumferential surface of the floating seal seat 3 is provided with a first annular boss 32, the magnetic ring 6 is located between the second pole shoe 43 and the first annular boss 32 and abuts against the first annular boss 32, so that the first sealing component 4 is axially positioned by the first end cover 5 and the first annular boss 32, and the first sealing component 4 is limited in the inner cavity of the floating seal seat 3 along the axial direction of the rotating shaft 2.

[0065] Specifically, the first end cover 5 and the magnetic ring 6 can be located in the inner cavity of the floating seal seat 3. The first end cover 5 can be threadedly connected to the floating seal seat 3 to ensure the connection reliability between the two, and at the same time facilitate the disassembly and assembly of the floating seal structure, reducing the subsequent maintenance cost.

[0066] like Figure 1 As shown, in some embodiments, the sealing device also includes a first magnetic isolation ring 7, which is sleeved on the rotating shaft 2 and located in the inner cavity of the floating sealing seat 3, and the two end surfaces of the first magnetic isolation ring 7 opposite to each other along the axial direction of the rotating shaft 2 are respectively abutted against the second pole shoe 43 and the magnetic conductive ring 6. In other words, the first magnetic isolation ring 7 is clamped between the second pole shoe 43 and the magnetic conductive ring 6.

[0067] like Figure 1 As shown, in some embodiments, the sealing device also includes a second sealing component 8, which is matched with the chamber 11 and is sleeved on the rotating shaft 2. The second sealing component 8 and the first sealing component 4 are arranged along the axial direction of the rotating shaft 2 and are closer to the high-pressure side than the first sealing component 4, so that the second sealing component 8 separates the first sealing component 4 from the high-pressure side, reduces the influence of the high-pressure gas on the high-pressure side on the sealing performance of the first sealing component 4, and improves the sealing reliability of the sealing device.

[0068] For example, taking the figure as an example, the right side of the housing 1 in the sealing device can be the high-pressure side, and the left side of the housing 1 can be the low-pressure side.

[0069] like Figure 1 and Figure 3 As shown, in some embodiments, the second sealing assembly 8 and the second pole shoe 43 are arranged on both sides of the magnetic ring 6 along the axial direction of the rotating shaft 2. In other words, the second sealing assembly 8 is closer to the high-pressure side than the second pole shoe 43, and the floating sealing seat 3 and the magnetic ring 6 are both movably connected to the second sealing assembly 8 along the radial direction of the rotating shaft 2.

[0070] The second sealing assembly 8 includes a third pole shoe 81, a second permanent magnet 82 and a fourth pole shoe 83 which are sequentially arranged from the inside to the outside. Each of the third pole shoe 81 and the fourth pole shoe 83 is provided with a second pole tooth 84 on the end face adjacent to the magnetic conductive ring 6. A micro-nano magnetic medium is adsorbed between the second pole tooth 84 and the magnetic conductive ring 6. The magnetic pole direction of the second permanent magnet 82 is perpendicular to the axial direction of the rotating shaft 2.

[0071] It can be understood that the second sealing component 8 forms an end face micro-nano magnetic medium seal in the sealing device, and the first magnetic isolation ring 7 can separate the axial micro-nano magnetic medium seal and the end face micro-nano magnetic medium seal so that the two micro-nano magnetic medium sealing forms do not interfere with each other, thereby ensuring the working performance of both. The magnetic circuit of the second sealing component 8 is: the magnetic field emitted from the N pole of the second permanent magnet 82 passes through the third pole shoe 81, the magnetic conductive ring 6 and the fourth pole shoe 83 and returns to the S pole of the second permanent magnet 82.

[0072] Specifically, the second permanent magnet 82 may be an annular permanent magnet. The magnetic pole direction of the second permanent magnet 82 is perpendicular to the axial direction of the rotating shaft 2, that is, the N pole and the S pole of the second permanent magnet 82 are arranged along the radial direction of the rotating shaft 2, such as the S pole of the second permanent magnet 82 is located at the outer ring of the N pole, or the N pole of the second permanent magnet 82 is located at the outer ring of the S pole.

[0073] Furthermore, the magnetic pole of the first permanent magnet 42 adjacent to the second pole shoe 43 is the same as the magnetic pole of the second permanent magnet 82 adjacent to the fourth pole shoe 83. Since air will leak magnetic flux, the first permanent magnet 42 and the second permanent magnet 82 adopt the aforementioned layout structure, which will not weaken the magnetic properties of the magnets.

[0074] For example, the installation direction of the first permanent magnet 42 is left N pole and right S pole, and the corresponding installation direction of the second permanent magnet 82 is inner N pole and outer S pole; or, the installation direction of the first permanent magnet 42 is left S pole and right N pole, and the corresponding installation direction of the second permanent magnet 82 is inner S pole and outer N pole.

[0075] Furthermore, a second sealing ring 85 is sandwiched between the outer circumference of the fourth pole shoe 83 and the inner circumference of the chamber 11 to further ensure the sealing performance of the sealing device.

[0076] For example, taking the figure as an example, an annular groove may be provided on the outer circumferential surface of the fourth pole shoe 83 , and the second sealing ring 85 may be fitted in the annular groove and abut against the inner circumferential surface of the chamber 11 .

[0077] like Figure 1 and Figure 4 As shown, in some embodiments, a boss 61 is provided on the end surface of the magnetic ring 6 adjacent to the second sealing assembly 8 , the boss 61 is spaced apart from the first annular shoulder 32 in the radial direction of the rotating shaft 2 , and the second pole tooth 84 is located between the boss 61 and the first annular shoulder 32 .

[0078] There are a plurality of second pole teeth 84 arranged at intervals in the radial direction of the rotating shaft 2. A third gap 86 is defined between the second pole tooth 84 closest to the boss 61 and the boss 61, that is, the first second pole tooth 84 close to the inner circumference of the third pole shoe 81 is spaced apart from the magnetic conductive ring 6 in the radial direction of the rotating shaft 2. A fourth gap 87 is defined between the second pole tooth 84 closest to the first annular shoulder 32 and the first annular shoulder 32, that is, the first second pole tooth 84 close to the outer circumference of the fourth pole shoe 83 is spaced apart from the floating seal seat 3 in the radial direction of the rotating shaft 2. The third gap 86 and the fourth gap 87 are both larger than the first gap 21. In other words, each of the third gap 86 and the fourth gap 87 is larger than the first gap 21 everywhere in the circumferential direction of the rotating shaft 2.

[0079] It can be understood that when the floating sealing structure moves radially along the rotating shaft 2 (i.e. floats), based on the above conditions, the second pole tooth 84 in the third pole shoe 81 closest to the boss 61 will not collide with the boss 61, and the second pole tooth 84 in the fourth pole shoe 83 closest to the first annular shoulder 32 will not collide with the first annular shoulder 32.

[0080] Preferably, the plurality of second pole teeth 84 are arranged at equal intervals along the radial direction of the rotating shaft 2 to ensure uniform force on all the pole teeth in the third pole shoe 81 and the fourth pole shoe 83 .

[0081] like Figure 1 and Figure 4 As shown, in some embodiments, the sealing device also includes a labyrinth sealing ring 9, an air flow channel for accommodating the labyrinth sealing ring 9 is defined between the inner circumference of the third pole shoe 81 and the outer circumference of the rotating shaft 2, the labyrinth sealing ring 9 is sleeved on the rotating shaft 2 and connected to the third pole shoe 81, the inner circumference of the labyrinth sealing ring 9 is provided with sealing teeth 91, a fifth gap 92 is defined between the sealing teeth 91 and the outer circumference of the rotating shaft 2, a sixth gap 62 is defined between the inner circumference of the magnetic ring 6 and the outer circumference of the rotating shaft 2, the fifth gap 92 is smaller than the sixth gap 62, in other words, the maximum distance from the sealing teeth 91 to the outer circumference of the rotating shaft 2 is smaller than the minimum distance from the inner circumference of the magnetic ring 6 to the outer circumference of the rotating shaft 2, or in other words, the sealing teeth 91 are closer to the rotating shaft 2 than the magnetic ring 6.

[0082] It is understandable that the labyrinth seal ring 9 can effectively increase the flow resistance of the airflow by the seal teeth 91 during the non-steady-state flow process of the airflow during pressurization (i.e., filling the sealed chamber of the sealed device with high-pressure gas), reduce the pressure of the high-pressure gas, and make the micro-nano magnetic medium contact the airflow with lower energy, thereby effectively preventing the micro-nano magnetic medium film from being broken during the pressurization process. At the same time, because the fifth gap 92 is smaller than the sixth gap 62, when the shaft 2 undergoes radial runout, the labyrinth seal ring 9 will contact the shaft 2 before the magnetic ring 6, so that the second sealing component 8 (i.e., the end face micro-nano magnetic medium sealing structure) has good anti-collision and wear performance.

[0083] Furthermore, there are multiple sealing teeth 91 and they are arranged at intervals along the axial direction of the rotating shaft 2. Preferably, the multiple sealing teeth 91 are arranged at equal intervals along the axial direction of the rotating shaft 2 to ensure uniform force on all the sealing teeth 91 in the labyrinth sealing ring 9.

[0084] Furthermore, the sealing teeth 91 are sawtooth, wherein the sealing teeth 91 closest to the magnetic ring 6 are inclined in the direction from the second pole shoe 43 toward the first pole shoe 41, and the remaining sealing teeth 91 are inclined in the direction from the first pole shoe 41 toward the second pole shoe 43. In other words, taking the figure as an example, there are three sealing teeth 91, that is, the leftmost sealing tooth 91 is a conical bevel tooth inclined toward the left side, and the two sealing teeth 91 on the right are conical bevel teeth inclined toward the right side.

[0085] It can be understood that, with the above-mentioned structural design, in the non-steady-state process of airflow during pressurization, the two sealing teeth 91 on the right side of the labyrinth sealing ring 9 are used to increase the airflow resistance to reduce the pressure of the high-pressure gas, thereby protecting the micro-nano magnetic medium from being impacted by airflow with lower energy, that is, to prevent the micro-nano magnetic medium from being "blown away" by the high-energy airflow, thereby enabling artificial pressurization to increase the gas flow and reduce the artificial pressurization time, while the first sealing tooth 91 on the left side can guide more airflow into the axial micro-nano magnetic medium seal, so that less airflow enters the end face micro-nano magnetic medium seal. At the same time, the chamber 11 formed between the first sealing tooth 91 on the left side and the magnetic ring 6 can cause the airflow to form a vortex, so that the energy of the airflow entering the end face micro-nano magnetic medium seal is lower, thereby improving the pressure resistance of the end face micro-nano magnetic medium seal during the pressurization process, and then isolating the second gap 31 (that is, the chamber formed by the housing 1 and the floating seal seat 3) from the high-pressure side.

[0086] like Figure 1 and Figure 2 As shown, in some embodiments, the sealing device further includes a second end cover 12 , which is sleeved on the rotating shaft 2 and connected to the housing 1 , and the second end cover 12 is suitable for sealing the chamber 11 .

[0087] Specifically, the second end cover 12 may be located in the chamber 11. The second end cover 12 may be threadedly connected to the housing 1 to ensure the reliability of the connection between the two, and at the same time facilitate the disassembly and assembly of the sealing device, thereby reducing the subsequent maintenance cost.

[0088] like Figure 1 and Figure 2 As shown, in some embodiments, the sealing device also includes a second magnetic isolation ring 13, which is matched with the chamber 11 and is sleeved on the rotating shaft 2. The second magnetic isolation ring 13 is located between the second end cover 12 and the floating seal seat 3, and the end face of the second magnetic isolation ring 13 facing away from the floating seal seat 3 abuts against the second end cover 12.

[0089] like Figures 1 to 3 As shown, in some embodiments, the floating seal seat 3 has a first end face and a second end face opposite to each other along the axial direction of the rotating shaft 2, and the outer periphery of each of the first end face and the second end face of the floating seal seat 3 is provided with a ball retainer 33, and the ball retainer 33 and the floating seal seat 3 form an annular groove.

[0090] A ball 34 is provided in the annular groove, at least part of the ball 34 protrudes out of the annular groove along the axial direction of the rotating shaft 2 and is in rolling contact with the second magnetic isolation ring 13 or the fourth pole shoe 83, so as to facilitate the radial movement of the floating seal seat 3 relative to the chamber 11 along the rotating shaft 2.

[0091] It can be understood that by installing the ball retainer 33 and the ball 34 structure on the floating seal seat 3, the friction between the floating seal structure and the second magnetic isolation ring 13 and the fourth pole shoe 83 can be effectively reduced when the floating seal structure adaptively adjusts the concentricity with the radial runout of the rotating shaft 2, so that the floating seal structure is easier to move (i.e. float).

[0092] Furthermore, there are a plurality of balls 34 arranged along the circumference of the annular groove, and any two adjacent balls 34 are in rolling contact.

[0093] Specifically, the ball 34 may be made of a material having both self-lubricating properties and relatively high hardness.

[0094] like Figure 1 As shown, in some embodiments, the sealing device also includes a first bearing 14 and a second bearing 15, both of which are fitted in the chamber 11 and sleeved on the rotating shaft 2, and each of the first bearing 14 and the second bearing 15 is closer to the high-pressure side than the second sealing assembly 8.

[0095] The rotating shaft 2 is provided with a shoulder 22, and the inner circumferential surface of the outer shell 1 is provided with a second annular boss 16. The two opposite end surfaces of the shoulder 22 along the axial direction of the rotating shaft 2 are respectively abutted against the first bearing 14 and the second bearing 15. The end surface of the first bearing 14 facing away from the shoulder 22 is abutted against the fourth pole shoe 83 through the third magnetic isolation ring 17. The third magnetic isolation ring 17 is matched with the chamber 11 and is sleeved on the rotating shaft 2. The end surface of the second bearing 15 facing away from the shoulder 22 is abutted against the second annular boss 16.

[0096] It is understandable that the floating seal structure, the second seal assembly 8 , the labyrinth seal ring 9 , the first bearing 14 and the second bearing 15 can be axially positioned by the cooperation between the second end cover 12 and the second annular boss 16 to limit the aforementioned components in the chamber 11 .

[0097] Specifically, both the first bearing 14 and the second bearing 15 may be deep groove ball bearings.

[0098] like Figure 1 As shown, in some embodiments, the housing 1 is suitable for being connected to the sealed device and is provided with a third sealing ring 18. The third sealing ring 18 is clamped between the housing 1 and the sealed device to seal the connection gap between the two, further ensuring the sealing reliability of the sealing device.

[0099] For example, the housing 1 may be connected to the sealed device via a flange, an end surface of the flange may be provided with an annular groove, and the third sealing ring 18 may fit into the annular groove.

[0100] It should be noted that the floating seal seat 3, the first end cover 5, the first magnetic isolation ring 7, the ball retainer 33 and the ball 34 can all be made of lightweight non-magnetic materials; the outer shell 1, the labyrinth seal ring 9, the second end cover 12, the first bearing 14 and the second bearing 15 can all be made of non-magnetic materials, or the outer shell 1, the labyrinth seal ring 9, the second end cover 12, the first bearing 14 and the second bearing 15 can all be provided with a non-magnetic material coating; the first pole shoe 41, the second pole shoe 43 and the magnetic ring 6 can all be made of lightweight magnetic materials; the rotating shaft 2, the third pole shoe 81 and the fourth pole shoe 83 can all be made of magnetic materials; the first permanent magnet 42 and the second permanent magnet 82 can both be made of neodymium iron boron material.

[0101] Therefore, compared with the related art, the present invention has the following advantages:

[0102] 1) Under the action of fluid dynamic pressure effect, the axial micro-nano magnetic medium seal has follow-up property, and the gap between it and the rotating shaft 2 changes with the radial runout of the rotating shaft 2, thereby improving the concentricity of the rotating shaft 2 relative to the first sealing component 4, reducing the influence of the radial runout of the rotating shaft 2, and improving the pressure resistance and service life of the sealing device;

[0103] 2) The setting of the labyrinth seal ring 9 can protect the micro-nano magnetic medium from being impacted by airflow with relatively small energy during the pressurization process, thereby reducing the manual pressurization time and improving production efficiency.

[0104] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0105] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0106] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0107] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0108] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0109] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A follow-up micro-nano magnetic medium sealing device, characterized in that: include: A housing and a shaft, wherein the housing has a chamber, the shaft is pivotally connected to the chamber and at least one end of the shaft is located outside the housing; as well as A floating seal seat and a first seal assembly, wherein the rotating shaft, the first seal assembly and the floating seal seat are sequentially sleeved from the inside to the outside, the floating seal seat and the first seal assembly are both matched with the chamber and movably connected with the chamber along the radial direction of the rotating shaft, the first seal assembly comprises a first pole shoe, a first permanent magnet and a second pole shoe sequentially arranged along the axial direction of the rotating shaft, and the magnetic pole direction of the first permanent magnet is consistent with the axial direction of the rotating shaft; A first gap is defined between the inner circumference of each of the first pole shoe and the second pole shoe and the outer circumference of the rotating shaft, and a micro-nano magnetic medium is adsorbed in the first gap. A second gap connected to the outside is defined between the outer circumference of the floating seal seat and the inner circumference of the chamber.

2. The follow-up micro-nano magnetic medium sealing device according to claim 1, characterized in that: Each of the first pole shoe and the second pole shoe is provided with a first pole tooth, the first pole teeth are in plurality and are arranged at intervals along the axial direction of the rotating shaft, and the first gap is defined between all the first pole teeth and the outer peripheral surface of the rotating shaft; And / or, the first gap is smaller than the second gap.

3. The follow-up micro-nano magnetic medium sealing device according to claim 1, characterized in that: Also includes: A first end cover and a magnetic conductive ring, wherein the first end cover and the magnetic conductive ring are both sleeved on the rotating shaft and are arranged on both sides of the first sealing assembly along the axial direction of the rotating shaft, the first end cover is connected to the floating sealing seat, the end surface of the first pole shoe facing away from the first permanent magnet abuts against the first end cover, the inner circumference of the floating sealing seat is provided with a first annular convex shoulder, and the magnetic conductive ring is located between the second pole shoe and the first annular convex shoulder and abuts against the first annular convex shoulder; and / or The first magnetic isolation ring is sleeved on the rotating shaft and located in the inner cavity of the floating seal seat. The first magnetic isolation ring has two opposite end surfaces along the axial direction of the rotating shaft respectively abutting against the second pole shoe and the magnetic conductive ring.

4. The follow-up micro-nano magnetic medium sealing device according to claim 3 is characterized in that: It also includes a second sealing component, which is matched with the chamber and sleeved on the rotating shaft. The second sealing component and the first sealing component are arranged along the axial direction of the rotating shaft and are closer to the high-pressure side than the first sealing component.

5. The follow-up type micro-nano magnetic medium sealing device according to claim 4, characterized in that: The second sealing assembly and the second pole shoe are respectively arranged on both sides of the magnetic conductive ring along the axial direction of the rotating shaft, and the floating sealing seat and the magnetic conductive ring are both movably connected to the second sealing assembly along the radial direction of the rotating shaft; The second sealing assembly includes a third pole shoe, a second permanent magnet and a fourth pole shoe which are sequentially sleeved from the inside to the outside, each of the third pole shoe and the fourth pole shoe is provided with a second pole tooth adjacent to the end face of the magnetic conductive ring, a micro-nano magnetic medium is adsorbed between the second pole tooth and the magnetic conductive ring, and the magnetic pole direction of the second permanent magnet is perpendicular to the axial direction of the rotating shaft.

6. The follow-up micro-nano magnetic medium sealing device according to claim 5, characterized in that: The end surface of the magnetic conductive ring adjacent to the second sealing assembly is provided with a boss, the boss is spaced apart from the first annular shoulder in the radial direction of the rotating shaft, and the second pole tooth is located between the boss and the first annular shoulder; There are multiple second pole teeth and they are arranged at intervals along the radial direction of the rotating shaft. A third gap is defined between the second pole tooth closest to the boss and the boss. A fourth gap is defined between the second pole tooth closest to the first annular shoulder and the first annular shoulder. Both the third gap and the fourth gap are larger than the first gap.

7. The follow-up type micro-nano magnetic medium sealing device according to claim 5, characterized in that: It also includes a labyrinth sealing ring, an air flow channel for accommodating the labyrinth sealing ring is defined between the inner circumference of the third pole shoe and the outer circumference of the rotating shaft, the labyrinth sealing ring is sleeved on the rotating shaft and connected to the third pole shoe, the inner circumference of the labyrinth sealing ring is provided with sealing teeth, a fifth gap is defined between the sealing teeth and the outer circumference of the rotating shaft, a sixth gap is defined between the inner circumference of the magnetic ring and the outer circumference of the rotating shaft, and the fifth gap is smaller than the sixth gap.

8. The follow-up type micro-nano magnetic medium sealing device according to claim 7, characterized in that: The sealing teeth are in plurality and are arranged at intervals along the axial direction of the rotating shaft; And / or, the sealing teeth are saw teeth, wherein the sealing teeth closest to the magnetic conductive ring are inclined in the direction from the second pole shoe toward the first pole shoe, and the remaining sealing teeth are inclined in the direction from the first pole shoe toward the second pole shoe.

9. The follow-up type micro-nano magnetic medium sealing device according to claim 7, characterized in that: Also includes: a second end cover, the second end cover is sleeved on the rotating shaft and connected to the housing, and the second end cover is suitable for sealing the chamber; and / or The second magnetic isolation ring is matched with the chamber and sleeved on the rotating shaft. The second magnetic isolation ring is located between the second end cover and the floating seal seat. The end surface of the second magnetic isolation ring facing away from the floating seal seat abuts against the second end cover.

10. The follow-up type micro-nano magnetic medium sealing device according to claim 9, characterized in that: The floating seal seat has a first end face and a second end face opposite to each other along the axial direction of the rotating shaft, and a ball retainer is provided on the outer periphery of each of the first end face and the second end face of the floating seal seat, and the ball retainer and the floating seal seat form an annular groove; A ball is arranged in the annular groove, at least part of which protrudes out of the annular groove along the axial direction of the rotating shaft and is in rolling contact with the second magnetic isolation ring or the fourth pole shoe, so as to facilitate the radial movement of the floating seal seat relative to the chamber along the rotating shaft.

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