Anti-collision micro-nano magnetic medium sealing device

Abstract

The invention provides an anti-collision and anti-abrasion micro-nano magnetic medium sealing device, and relates to the technical field of sealing devices, the anti-collision and anti-abrasion micro-nano magnetic medium sealing device comprises a shell, a rotating shaft and a sealing assembly, the shell is provided with a cavity, the rotating shaft is pivotally connected with the cavity, and at least one end is located outside the shell; the sealing assembly is matched with the cavity and arranged on the rotating shaft in a sleeving mode, the sealing assembly comprises a first pole shoe, a first labyrinth sealing ring and a second pole shoe which are sequentially arranged in the axial direction of the rotating shaft, an annular permanent magnet is arranged between the first pole shoe and the second pole shoe, and the annular permanent magnet is located in the cavity and arranged on the first labyrinth sealing ring in a sleeving mode. A first gap is defined between the inner circumferential surface of the first labyrinth sealing ring and the outer circumferential surface of the rotating shaft, a second 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 second gap, and the first gap is smaller than the second gap. According to the invention, the pressure resistance of the micro-nano magnetic medium seal can be ensured in a vibration environment, and the problem of collision and abrasion between radial run-out of the rotating shaft and the pole shoe is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of sealing devices, and in particular to an anti-collision and wear micro-nano magnetic medium sealing device. Background Art

[0002] Micro-nano magnetic medium sealing is a sealing method that uses magnetic field to bind micro-nano magnetic medium in the sealing gap to effectively prevent medium leakage and achieve sealing effect. It has the technical advantages of "zero leakage" and long service life.

[0003] In a vibrating environment, the high-frequency radial runout of the shaft is likely to damage the bearing, which reduces the reliability of the micro-nano magnetic medium seal and shortens its service life. After the bearing is removed, the high-frequency radial runout of the shaft may cause the pole teeth of the pole shoe to rub against the shaft. Therefore, when micro-nano magnetic medium seals are used in related technologies, rubbing is often avoided by increasing the sealing gap between the pole teeth and the shaft. However, the increase in the sealing gap will cause the pressure resistance of the micro-nano magnetic medium seal to decrease, making it impossible for the micro-nano magnetic medium seal to avoid rubbing between the pole teeth and the shaft while ensuring the pressure resistance. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes an anti-collision and wear micro-nano magnetic medium sealing device, which can ensure the pressure resistance of the micro-nano magnetic medium seal in a vibration environment and effectively avoid the collision and wear problem between the radial runout of the rotating shaft and the pole shoe.

[0006] According to an embodiment of the present invention, an anti-collision and wear micro-nano magnetic medium sealing device includes a shell, a rotating shaft and a sealing assembly, 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 sealing assembly is matched with the chamber and is sleeved on the rotating shaft, the sealing assembly includes a first pole shoe, a first labyrinth sealing ring and a second pole shoe arranged in sequence along the axial direction of the rotating shaft, an annular permanent magnet is provided between the first pole shoe and the second pole shoe, the annular permanent magnet is located in the chamber and is sleeved on the first labyrinth sealing ring, a first gap is defined between the inner circumference of the first labyrinth sealing ring and the outer circumference of the rotating shaft, a second 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, a micro-nano magnetic medium is adsorbed in the second gap, and the first gap is smaller than the second gap.

[0007] According to the anti-collision and wear micro-nano magnetic medium sealing device of the embodiment of the present invention, a micro-nano magnetic medium sealing structure is formed on the rotating shaft by the cooperation of the first pole shoe, the second pole shoe, the annular permanent magnet and the micro-nano magnetic medium, and the first labyrinth sealing ring constructs a labyrinth sealing structure. The combined sealing method of the two can ensure the sealing effect. At the same time, because the first gap is smaller than the second gap, that is, the inner circumference of the first labyrinth sealing ring is closer to the rotating shaft than the inner circumference of each of the first pole shoe and the second pole shoe, when the rotating shaft radially jumps out under a vibration environment, the first labyrinth sealing ring will contact the rotating shaft before the first pole shoe and the second pole shoe, so as to rub against the rotating shaft, which not only avoids magnetic leakage, but also effectively prevents the problem of damage of the pole teeth of each of the first pole shoe and the second pole shoe due to collision and wear. Compared with the related art, the present invention does not increase the sealing gap between the pole teeth of the pole shoe and the rotating shaft, and can ensure the pressure resistance of the micro-nano magnetic medium seal under a vibration environment, and effectively avoid the problem of radial jump of the rotating shaft and collision and wear between the pole shoes.

[0008] In some embodiments, the first labyrinth sealing ring is movably connected to the chamber along the radial direction of the rotating shaft, a third gap is defined between the outer circumference of the annular permanent magnet and the inner circumference of the chamber, and the sum of the first gap and the third gap is smaller than the second gap.

[0009] In some embodiments, the spacing between the first pole piece and the second pole piece is equal to the axial length of the first labyrinth sealing ring, and the axial length of the annular permanent magnet is equal to the axial length of the first labyrinth sealing ring.

[0010] In some embodiments, the first pole piece is closer to the high-pressure side of the sealed component than the second pole piece, and the sealing assembly further includes a second labyrinth sealing ring, wherein the second labyrinth sealing ring and the first labyrinth sealing ring are respectively arranged on both sides of the first pole piece along the axial direction of the rotating shaft;

[0011] A fourth gap is defined between the inner circumferential surface of the second labyrinth sealing ring and the outer circumferential surface of the rotating shaft, and the fourth gap is smaller than the second gap.

[0012] In some embodiments, the second labyrinth sealing ring is movably connected to the chamber along the radial direction of the rotating shaft, a fifth gap is defined between the outer circumference of the second labyrinth sealing ring and the inner circumference of the chamber, and the sum of the fourth gap and the fifth gap is smaller than the second gap.

[0013] Further, the fourth gap is equal to the first gap, and the third gap is equal to the fifth gap.

[0014] In some embodiments, a hardness of each of the first labyrinth seal ring and the second labyrinth seal ring is greater than a hardness of the rotating shaft.

[0015] In some embodiments, each of the first labyrinth sealing ring and the second labyrinth sealing ring is provided with sealing teeth on the wall surface adjacent to the rotating shaft, and the sealing teeth of at least one of the first labyrinth sealing ring and the second labyrinth sealing ring are serrated and inclined in a direction from the second pole shoe toward the first pole shoe.

[0016] Furthermore, there are multiple sealing teeth, and the multiple sealing teeth are arranged at intervals along the axial direction of the rotating shaft. The tooth tops of all the sealing teeth in the first labyrinth sealing ring construct the inner circumferential surface of the first labyrinth sealing ring, and the tooth tops of all the sealing teeth in the second labyrinth sealing ring construct the inner circumferential surface of the second labyrinth sealing ring.

[0017] In some embodiments, a first sealing ring is sandwiched between the outer circumference of each of the first pole piece, the annular permanent magnet, the second pole piece, and the second labyrinth sealing ring and the inner circumference of the chamber.

[0018] Furthermore, the first sealing ring may be one of an O-shaped sealing ring, a V-shaped sealing ring and a rectangular sealing ring.

[0019] In some embodiments, the housing includes a shell and an end cover sleeved on the rotating shaft, the shell and the end cover are connected along the axial direction of the rotating shaft and jointly define the chamber, the inner circumferential surface of the shell is provided with a first annular shoulder, the end surface of the second labyrinth sealing ring facing away from the first pole piece abuts against the first annular shoulder, the end surface of the end cover adjacent to the chamber is provided with a second annular shoulder, and the end surface of the second pole piece facing away from the first labyrinth sealing ring abuts against the second annular shoulder;

[0020] The sealing assembly further comprises a magnetic isolation ring, and two end surfaces of the magnetic isolation ring opposite to each other along the axial direction of the rotating shaft are respectively in contact with the second labyrinth sealing ring and the first pole shoe.

[0021] In some embodiments, the shell is suitable for being connected to the sealed component and is provided with a second sealing ring, and the second sealing ring is sandwiched between the shell and the sealed component.

[0022] 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

[0023] Figure 1 Schematic diagram of the structure of an anti-collision and wear micro-nano magnetic medium sealing device according to an embodiment of the present invention.

[0024] Figure 2 It is a schematic diagram of the state of the anti-collision and wear micro-nano magnetic medium sealing device according to an embodiment of the present invention when the rotating shaft vibrates slightly.

[0025] Figure 3 It is a schematic diagram of the state of the anti-collision and wear micro-nano magnetic medium sealing device according to an embodiment of the present invention when the rotating shaft vibrates at a medium amplitude.

[0026] Figure 4 It is a schematic diagram of the state of the anti-collision and wear micro-nano magnetic medium sealing device according to an embodiment of the present invention when the rotating shaft vibrates greatly.

[0027] Reference numerals:

[0028] 1. housing; 11. chamber; 12. shell; 121. first annular boss; 122. second sealing ring; 13. end cover; 131. second annular boss;

[0029] 2. Rotating shaft;

[0030] 3. Sealing assembly; 31. First pole shoe; 311. Second gap; 32. First labyrinth sealing ring; 321. First gap; 322. Sealing teeth; 33. Second pole shoe; 34. Annular permanent magnet; 341. Third gap; 35. Second labyrinth sealing ring; 351. Fourth gap; 352. Fifth gap; 36. First sealing ring; 37. Magnetic isolation ring. DETAILED DESCRIPTION

[0031] 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.

[0032] like Figures 1 to 4 As shown, an anti-collision and wear micro-nano magnetic medium sealing device according to an embodiment of the present invention includes a shell 1, a rotating shaft 2 and a sealing assembly 3, wherein the shell 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 shell 1; the sealing assembly 3 is matched with the chamber 11 and is sleeved on the rotating shaft 2, the sealing assembly 3 includes a first pole shoe 31, a first labyrinth sealing ring 32 and a second pole shoe 33 arranged in sequence along the axial direction of the rotating shaft 2, an annular permanent magnet 34 is provided between the first pole shoe 31 and the second pole shoe 33, the annular permanent magnet 34 is located in the chamber 11 and is sleeved on the first labyrinth sealing ring 32, a first gap 321 is defined between the inner circumference of the first labyrinth sealing ring 32 and the outer circumference of the rotating shaft 2, a second gap 311 is defined between the inner circumference of each of the first pole shoe 31 and the second pole shoe 33 and the outer circumference of the rotating shaft 2, a micro-nano magnetic medium is adsorbed in the second gap 311, and the first gap 321 is smaller than the second gap 311.

[0033] According to the anti-collision and wear micro-nano magnetic medium sealing device of the embodiment of the present invention, the first pole shoe 31, the second pole shoe 33, the annular permanent magnet 34 and the micro-nano magnetic medium cooperate to form a micro-nano magnetic medium sealing structure on the rotating shaft 2, and the first labyrinth sealing ring 32 constructs a labyrinth sealing structure. The combined sealing method of the two can ensure the sealing effect. At the same time, because the first gap 321 is smaller than the second gap 311, that is, the inner circumference of the first labyrinth sealing ring 32 is closer to the rotating shaft 2 than the inner circumference of each of the first pole shoe 31 and the second pole shoe 33. Therefore, when the shaft 2 undergoes radial runout under a vibration environment, the first labyrinth sealing ring 32 will contact the shaft 2 before the first pole shoe 31 and the second pole shoe 33, so as to rub against the shaft 2, thereby avoiding magnetic leakage and effectively preventing the pole teeth of each of the first pole shoe 31 and the second pole shoe 33 from being damaged due to rubbing. Compared with the related art, the present invention does not increase the sealing gap between the pole teeth of the pole shoe and the shaft 2, and can ensure the pressure resistance of the micro-nano magnetic medium seal under a vibration environment, effectively avoiding the radial runout of the shaft 2 and the rubbing problem between the pole shoes.

[0034] 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 sealing assembly 3 may be coaxially sleeved on the rotating shaft 2. The annular permanent magnet 34 may be coaxially sleeved on the first labyrinth sealing ring 32. The first pole shoe 31 and the second pole shoe 33 may have the same structure and specifications.

[0035] Taking the figure as an example, along the left and right direction, the part of the annular permanent magnet 34 adjacent to the first pole shoe 31 can be the N pole, and the part of the annular permanent magnet 34 adjacent to the second pole shoe 33 can be the S pole. At this time, the magnetic circuit of the micro-nano magnetic medium sealing structure is: the magnetic field emitted from the N pole of the annular permanent magnet 34 passes through the first pole shoe 31, the rotating shaft 2 and the second pole shoe 33 in sequence and then returns to the S pole of the annular permanent magnet 34 to form a magnetic circuit.

[0036] It is understandable that one end of the rotating shaft 2 is located outside the housing 1; or both ends of the rotating shaft 2 are located outside the housing 1. The sealing assembly 3 is located in the chamber 11. All the pole teeth in the first pole shoe 31 construct the inner circumference of the first pole shoe 31. All the pole teeth in the second pole shoe 33 construct the inner circumference of the second pole shoe 33. In addition, the present invention does not increase the sealing gap between the pole teeth of the pole shoe and the rotating shaft 2, so it will not cause a decrease in the pressure resistance of the micro-nano magnetic medium seal.

[0037] It should be noted that the present invention is not limited to application in the field of nuclear reactor main pump parts, but can also be applied to other sealing occasions where high-frequency radial runout of the rotating shaft 2 exists.

[0038] like Figure 1As shown, in some embodiments, the first labyrinth seal ring 32 is movably connected to the chamber 11 along the radial direction of the rotating shaft 2, wherein the radial direction of the rotating shaft 2 may be the up-down direction in the figure. A third gap 341 is defined between the outer circumference of the annular permanent magnet 34 and the inner circumference of the chamber 11, and the sum of the first gap 321 and the third gap 341 is smaller than the second gap 311, so that after the rotating shaft 2 radially jumps and contacts the first labyrinth seal ring 32, the annular permanent magnet 34 can move in the jumping direction of the rotating shaft 2, that is, the rotating shaft 2 pushes the first labyrinth seal ring 32 to move with the annular permanent magnet 34 in the jumping direction of the rotating shaft 2, thereby passively adjusting the magnetic field strength of the second gap 311 and reducing the influence of the radial jump of the rotating shaft 2 on the pressure resistance of the micro-nano magnetic medium.

[0039] It can be understood that the inner circumference of the chamber 11 is also the inner circumference of the housing 1. In addition, when the third gap 341 between the annular permanent magnet 34 and the housing 1 is reduced on one side, the gap between the annular permanent magnet 34 and the housing 1 in the opposite circumferential direction increases and a large gap is formed there. At this time, the radial distance between the annular permanent magnet 34 and the rotating shaft 2 on the large gap side is reduced, that is, the distance between the inner circumference of the annular permanent magnet 34 on the large gap side and the outer circumference of the rotating shaft 2 is reduced, so the magnetic field strength at the micro-nano magnetic medium on the large gap side can be increased to ensure the sealing pressure resistance of the micro-nano magnetic medium.

[0040] like Figure 1 As shown, in some embodiments, the spacing between the first pole piece 31 and the second pole piece 33 is equal to the axial length of the first labyrinth sealing ring 32 , so that the first pole piece 31 and the second pole piece 33 can realize axial positioning of the first labyrinth sealing ring 32 .

[0041] The axial length of the annular permanent magnet 34 is equal to the axial length of the first labyrinth seal ring 32 , that is, the axial length of the annular permanent magnet 34 is equal to the distance between the first pole shoe 31 and the second pole shoe 33 , so the axial positioning of the annular permanent magnet 34 can be guaranteed.

[0042] like Figure 1 As shown, in some embodiments, the first pole shoe 31 is closer to the high-pressure side of the sealed component than the second pole shoe 33, and the sealing assembly 3 also includes a second labyrinth sealing ring 35. The second labyrinth sealing ring 35 and the first labyrinth sealing ring 32 are respectively arranged on both sides of the first pole shoe 31 along the axial direction of the rotating shaft 2. In other words, the second labyrinth sealing ring 35 is closer to the high-pressure side of the sealed component than the first pole shoe 31.

[0043] A fourth gap 351 is defined between the inner circumference of the second labyrinth sealing ring 35 and the outer circumference of the rotating shaft 2 , and the fourth gap 351 is smaller than the second gap 311 , that is, the inner circumference of the second labyrinth sealing ring 35 is closer to the rotating shaft 2 than the inner circumference of each of the first pole shoe 31 and the second pole shoe 33 .

[0044] For example, taking the figure as an example, the second labyrinth seal ring 35 can be located on the left side of the first pole shoe 31, and the first labyrinth seal ring 32 can be located on the right side of the first pole shoe 31. At this time, the left side of the housing 1 in the sealing device can be the high-pressure side of the sealed component, and the right side of the housing 1 can be the low-pressure side of the sealed component.

[0045] It can be understood that after the sealing device is installed on the sealed component, in the process of filling the sealed chamber of the sealed component with high-pressure gas, the second labyrinth sealing ring 35 can reduce the energy of the high-pressure airflow to protect the micro-nano magnetic medium in the micro-nano magnetic medium sealing structure from being broken by the high-energy airflow. At the same time, because the fourth gap 351 is smaller than the second gap 311, when the shaft 2 undergoes radial runout, the second labyrinth sealing ring 35 will also contact the shaft 2 before the first pole shoe 31 and the second pole shoe 33, so as to rub against the shaft 2, further ensuring the reliability of the anti-collision and wear of the micro-nano magnetic medium sealing structure.

[0046] like Figure 1 As shown, in some embodiments, the second labyrinth sealing ring 35 is movably connected to the chamber 11 along the radial direction of the rotating shaft 2, and a fifth gap 352 is defined between the outer circumferential surface of the second labyrinth sealing ring 35 and the inner circumferential surface of the chamber 11, and the sum of the fourth gap 351 and the fifth gap 352 is smaller than the second gap 311, so that after the rotating shaft 2 radially jumps and contacts the second labyrinth sealing ring 35, the rotating shaft 2 can push the second labyrinth sealing ring 35 to move in the jumping direction of the rotating shaft 2, thereby cooperating with the first labyrinth sealing ring 32 to further improve the anti-collision and wear performance of the sealing device.

[0047] Furthermore, the fourth gap 351 is equal to the first gap 321, and the third gap 341 is equal to the fifth gap 352. In other words, the second labyrinth sealing ring 35 and the first labyrinth sealing ring 32 have the same radially variable range along the rotating shaft 2 in the chamber 11. Since the fourth gap 351 is equal to the first gap 321, when the rotating shaft 2 undergoes radial runout, the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 can basically move synchronously in the chamber 11.

[0048] It can be understood that the first gap 321 , the second gap 311 , the third gap 341 , the fourth gap 351 and the fifth gap 352 are all annular gaps.

[0049] like Figure 1 As shown, in some embodiments, the hardness of each of the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 is greater than the hardness of the rotating shaft 2, which can reduce the wear of the rotating shaft 2 on the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 and ensure the service life of the sealing device.

[0050] like Figure 1As shown, in some embodiments, each of the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 is provided with sealing teeth 322 on the wall surface adjacent to the rotating shaft 2, and the sealing teeth 322 of at least one of the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 are serrated and inclined in the direction from the second pole shoe 33 toward the first pole shoe 31. In other words, taking the figure as an example, the sealing teeth 322 are conical helical teeth inclined toward the left side.

[0051] Among them, the sealing teeth 322 of the first labyrinth sealing ring 32 are serrated and inclined in the direction from the second pole shoe 33 toward the first pole shoe 31; or, the sealing teeth 322 of the second labyrinth sealing ring 35 are serrated and inclined in the direction from the second pole shoe 33 toward the first pole shoe 31; or, the sealing teeth 322 of the first labyrinth sealing ring 32 and the sealing teeth 322 of the second labyrinth sealing ring 35 are both serrated and inclined in the direction from the second pole shoe 33 toward the first pole shoe 31.

[0052] It can be understood that, by adopting the above-mentioned structural design, during the non-steady-state flow process of pressurization (i.e., filling the sealed chamber of the sealed component with high-pressure gas), the sealing teeth 322 can effectively increase the flow resistance to the airflow, reduce the pressure of the high-pressure gas, and make the micro-nano magnetic medium contact with the airflow of lower energy, thereby effectively preventing the micro-nano magnetic medium film from being broken during the pressurization process.

[0053] Furthermore, there are multiple sealing teeth 322, and the multiple sealing teeth 322 are arranged at intervals along the axial direction of the rotating shaft 2. The tooth tops of all the sealing teeth 322 in the first labyrinth sealing ring 32 construct the inner circumferential surface of the first labyrinth sealing ring 32, and the tooth tops of all the sealing teeth 322 in the second labyrinth sealing ring 35 construct the inner circumferential surface of the second labyrinth sealing ring 35.

[0054] Preferably, the plurality of sealing teeth 322 are arranged at equal intervals along the axial direction of the rotating shaft 2 to ensure uniform force on all the sealing teeth 322 in the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 .

[0055] like Figure 1 As shown, in some embodiments, a first sealing ring 36 is sandwiched between the outer circumference of each of the first pole shoe 31, the annular permanent magnet 34, the second pole shoe 33 and the second labyrinth sealing ring 35 and the inner circumference of the chamber 11. The first sealing ring 36 can form a sealing structure between the aforementioned components and the inner circumference of the chamber 11. At the same time, when the rotating shaft 2 radially jumps, the friction loss between the aforementioned components and the inner circumference of the chamber 11 can be reduced.

[0056] For example, the outer circumference of at least one of the first pole shoe 31 , the annular permanent magnet 34 , the second pole shoe 33 and the second labyrinth seal ring 35 may be provided with an annular groove, and the first sealing ring 36 may be fitted in the annular groove and abut against the inner circumference of the chamber 11 .

[0057] Preferably, a first sealing ring 36 is sandwiched between the outer circumference of each of the first pole shoe 31, the annular permanent magnet 34, the second pole shoe 33 and the second labyrinth sealing ring 35 and the inner circumference of the chamber 11, and an annular groove may be opened on the outer circumference of each of the first pole shoe 31, the annular permanent magnet 34, the second pole shoe 33 and the second labyrinth sealing ring 35, and the first sealing ring 36 can be fitted in the annular groove and abut against the inner circumference of the chamber 11.

[0058] It should be noted that the specific specifications and shapes of the first pole shoe 31, the annular permanent magnet 34, the second pole shoe 33 and the first sealing ring 36 in the second labyrinth sealing ring 35 can be designed accordingly according to the requirements of the aforementioned components. In other words, the specific structures of the first sealing ring 36 on the aforementioned components are not necessarily the same.

[0059] like Figure 1 As shown, in some embodiments, the housing 1 includes a shell 12 and an end cover 13 which are sleeved on the rotating shaft 2. The shell 12 and the end cover 13 are connected along the axial direction of the rotating shaft 2 and jointly define a chamber 11. The inner circumferential surface of the shell 12 is provided with a first annular boss 121, and the end surface of the second labyrinth sealing ring 35 facing away from the first pole shoe 31 abuts against the first annular boss 121. The end surface of the end cover 13 adjacent to the chamber 11 is provided with a second annular boss 131, and the end surface of the second pole shoe 33 facing away from the first labyrinth sealing ring 32 abuts against the second annular boss 131.

[0060] The sealing assembly 3 also includes a magnetic isolation ring 37, and the two end faces of the magnetic isolation ring 37 opposite to each other along the axial direction of the rotating shaft 2 are respectively abutted against the second labyrinth sealing ring 35 and the first pole shoe 31. In other words, of the two end faces of the magnetic isolation ring 37 opposite to each other along the axial direction of the rotating shaft 2, one end face is abutted against the second labyrinth sealing ring 35, and the other end face is abutted against the first pole shoe 31.

[0061] It is understandable that the axial positioning of the second labyrinth sealing ring 35 can be achieved by cooperating with the first annular boss 121 and the magnetic isolation ring 37 , while the second annular boss 131 can limit the micro-nano magnetic medium sealing structure in the chamber 11 along the axial direction of the rotating shaft 2 .

[0062] Furthermore, the shell 12 is threadedly connected to the end cover 13, which ensures the reliability of the connection between the two, facilitates the disassembly and assembly of the sealing device, and reduces the subsequent maintenance cost.

[0063] like Figure 1 As shown, in some embodiments, the shell 12 is suitable for connecting with the sealed component and is provided with a second sealing ring 122. The second sealing ring 122 is clamped between the shell 12 and the sealed component to seal the connecting gap therebetween, further ensuring the sealing reliability of the sealing device in the sealed component.

[0064] For example, the housing 12 may be connected to the sealed component via a flange, an end surface of the flange may be provided with an annular groove, and the second sealing ring 122 may be fitted into the annular groove.

[0065] Furthermore, the first sealing ring 36 and the second sealing ring 122 can both be one of an O-shaped sealing ring, a V-shaped sealing ring and a rectangular sealing ring.

[0066] It should be noted that the outer shell 1, the first labyrinth sealing ring 32, the second labyrinth sealing ring 35 and the magnetic isolation ring 37 are all made of non-magnetic materials, or the outer shell 1, the first labyrinth sealing ring 32, the second labyrinth sealing ring 35 and the magnetic isolation ring 37 are all provided with a non-magnetic material coating; the rotating shaft 2, the first pole shoe 31 and the second pole shoe 33 are all made of magnetic materials, such as 2Cr13 material with good magnetic conductivity; the annular permanent magnet 34 can be a neodymium iron boron annular permanent magnet 34, and its magnetization direction is axial magnetization.

[0067] Therefore, compared with the related art, the present invention has the following advantages:

[0068] 1) When the rotating shaft 2 undergoes a small radial runout, the non-magnetic first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 contact the rotating shaft 2 before the first pole shoe 31 and the second pole shoe 33, thereby avoiding magnetic leakage;

[0069] 2) When the shaft 2 undergoes a moderate radial runout, the annular permanent magnet 34 moves in the direction of the runout of the shaft 2, passively adjusting the magnetic field strength of the sealing gap, thereby reducing the influence of the radial runout of the shaft 2 on the pressure resistance;

[0070] 3) When the shaft 2 undergoes a large radial runout, the first labyrinth seal ring 32 and the second labyrinth seal ring 35 collide with the shaft 2 before the first pole shoe 31 and the second pole shoe 33, thereby preventing the first pole shoe 31 and the second pole shoe 33 from being damaged due to collision and friction;

[0071] 4) The first sealing ring 36 (i.e., rubber ring) sandwiched between the annular permanent magnet 34 sleeved on the first labyrinth sealing ring 32 and the inner circumference of the chamber 11, and between the second labyrinth sealing ring 35 and the inner circumference of the chamber 11 can buffer the friction force and improve the reliability of the connection between the sealing element and the sealed element;

[0072] 5) The first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 can reduce the energy of the high-pressure airflow during the pressurization process, thereby protecting the micro-nano magnetic medium from being broken by the high-energy airflow.

[0073] Now, in combination with the amplitude of the radial runout of the rotating shaft 2, the working state of the sealing device is described, specifically:

[0074] like Figure 2As shown, when the rotating shaft 2 has a small radial runout, the first labyrinth sealing ring 32 and the second labyrinth sealing ring 35 contact the rotating shaft 2 before the first pole shoe 31 and the second pole shoe 33;

[0075] like Figure 3 As shown, when the shaft 2 undergoes a moderate radial runout, the shaft 2 pushes the first labyrinth seal ring 32 and the second labyrinth seal ring 35 to move radially along the shaft 2 until the first labyrinth seal ring 32 and the annular permanent magnet 34 are in contact with the inner circumference of the chamber 11, that is, the radial gap becomes 0. At this time, the first pole shoe 31 and the second pole shoe 33 are still not in contact with the outer circumference of the shaft 2.

[0076] like Figure 4 As shown, when the shaft 2 undergoes a large radial runout, the first labyrinth seal and the second labyrinth seal both rub against the outer peripheral surface of the shaft 2, thereby avoiding the problem of the first pole shoe 31 and the second pole shoe 33 being damaged by rubbing against the shaft 2.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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 micro-nano magnetic medium sealing device for preventing collision and wear, 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 sealing assembly, wherein the sealing assembly is matched with the chamber and is sleeved on the rotating shaft, the sealing assembly includes a first pole shoe, a first labyrinth sealing ring and a second pole shoe which are arranged in sequence along the axial direction of the rotating shaft, an annular permanent magnet is provided between the first pole shoe and the second pole shoe, the annular permanent magnet is located in the chamber and is sleeved on the first labyrinth sealing ring, a first gap is defined between the inner circumference of the first labyrinth sealing ring and the outer circumference of the rotating shaft, a second 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, a micro-nano magnetic medium is adsorbed in the second gap, and the first gap is smaller than the second gap.

2. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 1, characterized in that: The first labyrinth sealing ring is movably connected to the chamber along the radial direction of the rotating shaft, a third gap is defined between the outer circumference of the annular permanent magnet and the inner circumference of the chamber, and the sum of the first gap and the third gap is smaller than the second gap.

3. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 1, characterized in that: The distance between the first pole shoe and the second pole shoe is equal to the axial length of the first labyrinth seal ring, and the axial length of the annular permanent magnet is equal to the axial length of the first labyrinth seal ring.

4. The anti-collision and wear micro-nano magnetic medium sealing device according to any one of claims 1 to 3, characterized in that: The first pole shoe is closer to the high-pressure side of the sealed component than the second pole shoe, and the sealing assembly further includes a second labyrinth sealing ring, wherein the second labyrinth sealing ring and the first labyrinth sealing ring are respectively arranged on both sides of the first pole shoe along the axial direction of the rotating shaft; A fourth gap is defined between the inner circumferential surface of the second labyrinth sealing ring and the outer circumferential surface of the rotating shaft, and the fourth gap is smaller than the second gap.

5. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 4, characterized in that: The second labyrinth sealing ring is movably connected to the chamber along the radial direction of the rotating shaft, a fifth gap is defined between the outer circumference of the second labyrinth sealing ring and the inner circumference of the chamber, and the sum of the fourth gap and the fifth gap is smaller than the second gap.

6. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 4, characterized in that: The hardness of each of the first labyrinth seal ring and the second labyrinth seal ring is greater than the hardness of the rotating shaft.

7. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 4, characterized in that: Each of the first labyrinth seal ring and the second labyrinth seal ring is provided with sealing teeth on a wall surface adjacent to the rotating shaft, and the sealing teeth of at least one of the first labyrinth seal ring and the second labyrinth seal ring are saw teeth and are inclined in a direction from the second pole shoe toward the first pole shoe; And / or, there are a plurality of sealing teeth, and the plurality of sealing teeth are arranged at intervals along the axial direction of the rotating shaft.

8. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 4, characterized in that: A first sealing ring is sandwiched between the outer circumference of each of the first pole shoe, the annular permanent magnet, the second pole shoe and the second labyrinth sealing ring and the inner circumference of the chamber; And / or, the first sealing ring may be one of an O-shaped sealing ring, a V-shaped sealing ring and a rectangular sealing ring.

9. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 4, characterized in that: The housing comprises a shell and an end cover sleeved on the rotating shaft, the shell and the end cover are connected along the axial direction of the rotating shaft and define the chamber together, the inner circumferential surface of the shell is provided with a first annular convex shoulder, the end surface of the second labyrinth seal ring facing away from the first pole piece abuts against the first annular convex shoulder, the end surface of the end cover adjacent to the chamber is provided with a second annular convex shoulder, the end surface of the second pole piece facing away from the first labyrinth seal ring abuts against the second annular convex shoulder; The sealing assembly further comprises a magnetic isolation ring, and two end surfaces of the magnetic isolation ring opposite to each other along the axial direction of the rotating shaft are respectively in contact with the second labyrinth sealing ring and the first pole shoe.

10. The anti-collision and wear micro-nano magnetic medium sealing device according to claim 9, characterized in that: The housing is suitable for being connected to the sealed component and is provided with a second sealing ring, and the second sealing ring is sandwiched between the housing and the sealed component.

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