CN112431925A

CN112431925A - Magnetic liquid composite sealing device

Info

Publication number: CN112431925A
Application number: CN202011322506.6A
Authority: CN
Inventors: 李德才; 李艳文; 李泽鹏
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2020-11-23
Filing date: 2020-11-23
Publication date: 2021-03-02
Anticipated expiration: 2040-11-23
Also published as: CN112431925B

Abstract

The invention discloses a magnetic liquid composite sealing device which comprises a shell, a rotating shaft, a sealing assembly and an adsorption part, wherein a cavity is formed in the shell, the rotating shaft is rotatably arranged in the cavity, the sealing assembly is sleeved on the rotating shaft and is positioned in the cavity, the sealing assembly comprises a brush sealing part, a magnetic liquid sealing part and a labyrinth sealing part, the brush sealing part, the magnetic liquid sealing part and the labyrinth sealing part are respectively sleeved on the rotating shaft and are arranged at intervals in the axial direction of the rotating shaft, the brush sealing part is arranged adjacent to the sealing cavity, the magnetic liquid sealing part is arranged between the brush sealing part and the labyrinth sealing part, the adsorption part is arranged in the brush sealing part, and the adsorption part is used for adsorbing sealing media overflowing out of the sealing cavity. The magnetic liquid composite sealing device can improve the pressure resistance and the high and low temperature resistance, reduce the amount of dust entering the magnetic liquid and prolong the service life of the sealing device.

Description

Magnetic liquid composite sealing device

Technical Field

The invention belongs to the technical field of powder sealing, and particularly relates to a magnetic liquid composite sealing device.

Background

In mechanical devices, the seal is a critical component, and the loss caused by the failure of the seal due to the problem of the seal is not negligible. With the higher and higher sealing requirements of modern industries, a single sealing form is difficult to meet all requirements, especially under special working conditions such as high pressure difference and high temperature difference. The magnetic liquid seal has the advantages of zero leakage, no abrasion, simple structure, long service life, convenience in maintenance and the like, but the pressure resistance and the high and low temperature resistance of the magnetic liquid seal device are weaker, and when the magnetic liquid seal is in a dust environment, dust easily enters the seal device, so that the seal failure is caused, and the service life of the seal device is shortened.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, the embodiment of the invention provides a magnetic liquid composite sealing device, which can improve the pressure resistance and the high and low temperature resistance, reduce the amount of dust entering the magnetic liquid and prolong the service life of the magnetic liquid composite sealing device.

The magnetic liquid composite sealing device is used for sealing a sealing cavity and comprises a shell, wherein a cavity is formed in the shell; the rotating shaft is rotatably arranged in the cavity; a seal assembly fitted around the rotating shaft and located in the chamber, the seal assembly including a brush seal member, a magnetic liquid seal member, and a labyrinth seal member fitted around the rotating shaft, respectively, the brush seal member, the magnetic liquid seal member, and the labyrinth seal member being arranged at intervals in an axial direction of the rotating shaft and disposed adjacent to the seal chamber, the magnetic liquid seal member being disposed between the brush seal member and the labyrinth seal member; and the adsorption part is arranged in the brush type sealing part and is used for adsorbing the sealing medium overflowing from the sealing cavity.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the pressure resistance and the high and low temperature resistance can be improved, the amount of dust entering the magnetic liquid can be reduced, and the service life of the magnetic liquid composite sealing device is prolonged.

In some embodiments, an inner peripheral surface of the labyrinth seal member is provided with a plurality of projections arranged at intervals in an axial direction of the rotating shaft.

In some embodiments, the brush type sealing component includes a first baffle, a brush wire bundle, and a second baffle, the first baffle, the brush wire bundle, and the second baffle are respectively sleeved on the rotating shaft, the first baffle, the brush wire bundle, and the second baffle are arranged at intervals in the axial direction of the rotating shaft, the brush wire bundle is disposed between the first baffle and the second baffle, a first mounting hole penetrating through the first baffle in the axial direction of the rotating shaft is formed in the first baffle, the adsorption component is located in the first mounting hole, a second mounting hole penetrating through the second baffle in the axial direction of the rotating shaft is formed in the second baffle, and the adsorption component is located in the second mounting hole.

In some embodiments, the inner circumferential surfaces of the first baffle and the second baffle are respectively provided with a sealing tooth, and a preset gap is formed between the sealing tooth and the rotating shaft in the radial direction of the rotating shaft.

In some embodiments, the magnetic liquid sealing member includes a first pole piece, a second pole piece, and a permanent magnet, the first pole piece and the second pole piece are respectively sleeved on the rotating shaft, the first pole piece and the second pole piece are arranged in an axial direction of the rotating shaft at intervals, the permanent magnet is arranged between the first pole piece and the second pole piece, an inner circumference of the first pole piece is provided with a plurality of first pole teeth, the plurality of first pole teeth are arranged in an axial direction of the rotating shaft at intervals, a magnetic liquid is adsorbed between the plurality of first pole teeth and the rotating shaft, an inner circumference of the second pole piece is provided with a plurality of second pole teeth, the plurality of second pole teeth are arranged in an axial direction of the rotating shaft at intervals, and a magnetic liquid is adsorbed between the plurality of second pole teeth and the rotating shaft.

In some embodiments, grooves are formed in the outer peripheral surface of the first pole piece and the outer peripheral surface of the second pole piece, the magnetic liquid composite sealing device further includes a first sealing ring and a second sealing ring, the first sealing ring is arranged in the groove of the first pole piece, and the second sealing ring is arranged in the groove of the second pole piece.

In some embodiments, the magnetic liquid composite sealing device further includes an air supply assembly, the air supply assembly is located in the cavity, the air supply assembly is disposed on a side adjacent to the brush seal component, and the air supply assembly is located at an end far away from the magnetic liquid seal component, the air supply assembly includes a fixing plate and a plurality of air supply members, the fixing plate is sleeved on the rotating shaft, the plurality of air supply members are arranged at intervals in a circumferential direction of the fixing plate, and the air supply members supply air to the seal cavity.

In some embodiments, the magnetic-fluid composite sealing device further comprises an end cap disposed at one end of the housing, and the rotating shaft penetrates through the end cap.

In some embodiments, a groove is formed in an end of the housing opposite to the end cap, and the magnetic liquid composite sealing device further comprises a third sealing ring which is arranged in the groove of the housing.

Drawings

Fig. 1 is a schematic structural diagram of a magnetic fluid composite sealing device according to an embodiment of the present invention.

Fig. 2 is a schematic view of an installation manner of a brush wire bundle in the magnetic liquid composite sealing device according to the embodiment of the invention.

Reference numerals:

the housing 1, the chamber 101, the flange portion 102, the through hole 103,

the rotating shaft (2) is provided with a rotating shaft,

a sealing assembly 3, a brush sealing part 31, a first baffle 311, a first mounting hole 3111, a brush bundle 312, a second baffle 313, a second mounting hole 3131, a magnetic liquid sealing part 32, a first pole piece 321, a first pole tooth 3211, a second pole piece 322, a second pole tooth 3221, a permanent magnet 323, a labyrinth sealing part 33,

an adsorption part 4, a first sealing ring 5, a second sealing ring 6,

the air supply component 7, the fixing plate 71, the air supply piece 72, the end cover 8 and the third sealing ring 9.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

As shown in fig. 1 and fig. 2, the magnetic liquid composite sealing device according to the embodiment of the present invention is used for sealing a sealing cavity, where the sealing cavity is a sealing cavity provided in a device to be sealed or a device to be sealed, and the magnetic sealing device is provided outside the device to be sealed and connected to the device to be sealed, and is used for sealing the sealing cavity of the device to be sealed. The magnetic liquid composite sealing device comprises a shell 1, a rotating shaft 2, a sealing assembly 3 and an adsorption part 4.

The housing 1 has a chamber 101 therein. As shown in fig. 1, the left end of the housing 1 has a flange portion 102, the flange portion 102 is provided with a plurality of threaded holes, the flange portion 102 is suitable for being connected with a device to be sealed, and the flange portion 102 is disposed adjacent to the sealing cavity.

The shaft 2 is rotatably provided in the chamber 101. As shown in fig. 1, the rotating shaft 2 is rotatably disposed in the chamber 101, and the rotating shaft 2 extends in the left-right direction, and both left and right ends of the rotating shaft 2 extend out of the housing 1.

The seal assembly 3 is sleeved on the rotating shaft 2, the seal assembly 3 is located in the cavity 101, the seal assembly 3 comprises a brush seal part 31, a magnetic liquid seal part 32 and a labyrinth seal part 33, the brush seal part 31, the magnetic liquid seal part 32 and the labyrinth seal part 33 are respectively sleeved on the rotating shaft 2, the brush seal part 31, the magnetic liquid seal part 32 and the labyrinth seal part 33 are arranged at intervals in the axial direction (the left and right direction shown in fig. 1) of the rotating shaft 2, the brush seal part 31 is arranged adjacent to the seal cavity, and the magnetic liquid seal part 32 is arranged between the brush seal part 31 and the labyrinth seal part 33.

As shown in fig. 1, brush seal member 31 is located on the leftmost side of seal assembly 3, and labyrinth seal member 33 is located on the rightmost side of seal assembly 3. The magnetic liquid seal member 32 has a seal gap in the vertical direction with the rotating shaft 2, and magnetic liquid is adsorbed in the seal gap.

The suction member 4 is provided in the brush seal member 31, and the suction member 4 sucks the seal medium overflowing from the seal cavity. As shown in fig. 1, the number of the suction members 4 is plural, and the plural suction members 4 are arranged at intervals in the vertical direction. Specifically, the material of the adsorption member 4 is activated carbon, and it is understood that the material of the adsorption member 4 in the present application is not limited thereto, and may be, for example, activated alumina, molecular sieve, or the like.

According to the magnetic liquid composite sealing device of the embodiment of the invention, the brush type sealing part 31, the magnetic liquid sealing part 32 and the labyrinth sealing part 33 are arranged, the pressure resistance and the high and low temperature resistance can be improved by combining the brush type sealing part 31, the magnetic liquid sealing part 32 and the labyrinth sealing part 33, the amount of dust in a sealing cavity entering the magnetic liquid can be reduced by arranging the adsorption part 4, the amount of dust outside entering the magnetic liquid can be reduced by arranging the labyrinth sealing part 33, and the service life of the magnetic liquid composite sealing device is prolonged.

In some embodiments, the inner peripheral surface of the labyrinth seal member 33 is provided with a plurality of protrusions arranged at intervals in the axial direction of the rotating shaft 2. Preferably, the labyrinth seal part 33 is a filter plate, the inner circumference of the filter plate is provided with a plurality of protrusions arranged at intervals in the left and right directions to form labyrinth seals, the plurality of protrusions have a preset gap between the upper and lower directions and the rotating shaft 2, the size of the preset gap is 0.15mm to 0.3mm, and when the preset gap is 0.15mm to 0.3mm, the sealing performance can be improved, and the sealing medium is prevented from leaking to the outside. It is understood that the number of the protrusions in the present application is adapted to the size of the rotating shaft 2, and the present application is not particularly limited.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the labyrinth sealing part 33 is arranged, so that the pressure difference between the outside and the sealing cavity can be reduced, the sealing performance is improved, for example, when the sealing cavity needs vacuum sealing, such as metal powder sealing, the labyrinth sealing part 33 can reduce the pressure difference between the outside and the sealing cavity, so that the pressure born by the magnetic liquid sealing is reduced, the high-pressure resistance of the magnetic liquid composite sealing device is improved, and meanwhile, the magnetic liquid sealing can also meet the vacuum sealing requirement. And the labyrinth seal part 33 is a filter plate, so that external dust can be filtered, the external dust is reduced to enter the magnetic liquid, the cleanness of the magnetic liquid is kept, and the service life of the sealing device is prolonged.

In some embodiments, the brush seal member 31 includes a first blocking plate 311, a brush filament bundle 312, and a second blocking plate 313, the first blocking plate 311, the brush filament bundle 312, and the second blocking plate 313 are respectively sleeved on the rotating shaft 2, the first blocking plate 311, the brush filament bundle 312, and the second blocking plate 313 are spaced apart in the axial direction of the rotating shaft 2, and the brush filament bundle 312 is disposed between the first blocking plate 311 and the second blocking plate 313, a first mounting hole 3111 penetrating the first blocking plate 311 in the axial direction of the rotating shaft 2 is provided on the first blocking plate 311, the suction member 4 is located in the first mounting hole 3111, a second mounting hole 3131 penetrating the second blocking plate 313 in the axial direction of the rotating shaft 2 is provided on the second blocking plate 313, and the suction member 4 is located in the second mounting hole 3131.

As shown in fig. 1, the dimension of the first flapper 311 in the left-right direction and the dimension of the second flapper 313 in the left-right direction are substantially the same, and the outer peripheries of both the first flapper 311 and the second flapper 313 are in contact with the inner wall surface of the casing 1. The first mounting holes 3111 are plural, the plural first mounting holes 3111 are arranged at intervals in the vertical direction, the plural second mounting holes 3131 are plural, and the plural second mounting holes 3131 are arranged at intervals in the vertical direction. The number of the first mounting holes 3111 and the number of the second mounting holes 3131 are the same, and the sum of the number of the first mounting holes 3111 and the number of the second mounting holes 3131 is equal to the number of the suction members 4.

As shown in fig. 2, the installation angle of the brush filament bundle 312 is θ, θ is 40 ° to 60 °, and the installation angle θ of the brush filament bundle 312 in this application is α - β, where α is an angle between a tangent line (line B shown in fig. 2) of a contact point (point a shown in fig. 2) of the brush filament bundle 312 and the rotating shaft 2 and a line (line C shown in fig. 2) connecting the contact point and the center of the rotating shaft 2, and β is an angle between the brush filament bundle 312 and the tangent line.

In the magnetic liquid composite sealing device according to the embodiment of the invention, the first baffle 311, the second baffle 313 and the brush wire bundle 312 are respectively sleeved on the rotating shaft 2, so that the brush sealing part 31 can be conveniently mounted and dismounted, and when the brush sealing part 31 needs to be replaced and maintained, only the brush wire bundle 312 needs to be replaced, so that the maintenance cost is reduced. The brush wire bundle 312 is arranged along the inclination angle of 40-60 degrees, the radial displacement of the rotor can be absorbed, the free end of the brush wire bundle is ensured to be stressed the minimum when in contact, and the service life of the brush wire bundle 312 is prolonged. Moreover, the brush wire bundle 312 can prevent the sealing medium in the sealing cavity from entering the magnetic liquid, and the adsorption component 4 can adsorb the sealing medium, so that the amount of the sealing medium entering the magnetic liquid is reduced, and the service life of the magnetic liquid seal is prolonged.

In some embodiments, the inner circumferential surfaces of the first and

second baffles

311 and 313 are respectively provided with a sealing tooth having a predetermined gap from the rotating shaft 2 in the radial direction of the rotating shaft 2. The preset clearance between the seal teeth and the rotating shaft 2 is 0.5 mm-1 mm.

As shown in fig. 1, the right end surface of the first blocking plate 311 contacts the left end surface of the brush filament bundle 312, and the left end surface of the second blocking plate 313 contacts the right end surface of the brush filament bundle 312. The sealing teeth on the inner periphery of the first baffle 311 are single teeth, the cross section of the sealing teeth on the inner periphery of the first baffle 311 in the vertical direction is substantially in the shape of an isosceles triangle, the sealing teeth of the second baffle 313 are single teeth, the cross section of the sealing teeth on the inner periphery of the second baffle 313 in the vertical direction is substantially in the shape of a right-angled triangle, one right-angled side of the right-angled triangle is in contact with the right end face of the brush bristle bundle 312, and the other right-angled side of the right-angled triangle is in contact with the inner peripheral surface of the second baffle 313.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the single-tooth structure similar to labyrinth seal is formed by the sealing teeth, the range of the gap between the sealing teeth and the rotating shaft 2 is 0.5-1.0 mm, the impact of a sealed medium on the brush wire bundle 312 can be reduced, and the second baffle 313 can protect the brush wire bundle 312 from being deformed due to the impact of the sealed medium.

In some embodiments, the magnetic liquid sealing member 32 includes a first pole piece 321, a second pole piece 322, and a permanent magnet 323, the first pole piece 321 and the second pole piece 322 are respectively sleeved on the rotating shaft 2, the first pole piece 321 and the second pole piece 322 are arranged at intervals in the axial direction of the rotating shaft 2, the permanent magnet 323 is arranged between the first pole piece 321 and the second pole piece 322, an inner circumference of the first pole piece 321 is provided with a plurality of first pole teeth 3211, the plurality of first pole teeth 3211 are arranged at intervals in the axial direction of the rotating shaft 2, a magnetic liquid is adsorbed between the plurality of first pole teeth 3211 and the rotating shaft 2, an inner circumference of the second pole piece 322 is provided with a plurality of second pole teeth 3221, the plurality of second pole teeth 3221 are arranged at intervals in the axial direction of the rotating shaft 2, and a magnetic liquid is adsorbed between the plurality of second pole teeth 3221 and the rotating shaft 2.

As shown in fig. 1, the first pole piece 321 and the second pole piece 322 have the same size in the left-right direction, the left end of the first pole piece 321 is in contact with the right end surface of the second baffle 313, and the right end surface of the second pole piece 322 is in contact with the left end of the labyrinth seal member 33.

In some embodiments, grooves are formed on the outer peripheral surface of the first pole piece 321 and the outer peripheral surface of the second pole piece 322, the magnetic liquid sealing device further includes a first sealing ring 5 and a second sealing ring 6, the first sealing ring 5 is disposed in the groove of the first pole piece 321, and the second sealing ring 6 is disposed in the groove of the second pole piece 322.

According to the embodiment of the application, the first sealing ring 5 and the second sealing ring 6 are arranged, the sealing medium can be prevented from leaking between the outer circular surface of the pole shoe and the inner wall surface of the shell 1, and the sealing performance of magnetic liquid sealing is improved.

In some embodiments, the magnetic liquid composite sealing device further includes an air supply assembly 7, the air supply assembly 7 is located in the cavity 101, the air supply assembly 7 is disposed on a side adjacent to the brush seal component 31, the air supply assembly 7 is located at an end far away from the magnetic liquid seal component 32, the air supply assembly 7 includes a fixing plate 71 and a plurality of air supply members 72, the fixing plate 71 is sleeved on the rotating shaft 2, the plurality of air supply members 72 are spaced in a circumferential direction of the fixing plate 71, and the air supply members 72 supply air towards the seal cavity.

As shown in fig. 1, the air supply assembly 7 is located at the left side of the brush seal member 31, the plurality of air supply members 72 are connected to an external power source through wires, and the casing 1 is provided with a through hole 103 through which the wires pass through the through hole 103. The number of the air supply pieces 72 is 2-6, and specifically, the air supply pieces 72 are fans.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the air supply assembly 7 is arranged, so that air can be supplied into the sealing cavity, a sealing medium in the sealing cavity is not easy to enter the sealing device, and the service life of the sealing device is prolonged.

In some embodiments, the magnetic liquid composite sealing device further comprises an end cap 8, the end cap 8 is arranged at one end of the shell 1, and the rotating shaft 2 penetrates through the end cap 8. As shown in fig. 1, the end cap 8 is provided at the right end of the casing 1, the end cap 8 is connected to the casing 1 by a bolt, the rotating shaft 2 passes through the end cap 8, and the left end surface of the end cap 8 abuts against the right end surface of the labyrinth seal 33.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the end cover 8 is arranged, so that the sealing performance of the shell 1 is improved.

In some embodiments, the end of the housing 1 opposite to the end cap 8 is provided with a groove, and the magnetic liquid compound sealing device further comprises a third sealing ring 9, wherein the third sealing ring 9 is arranged in the groove of the housing 1. As shown in fig. 1, a groove is formed at the left end of the housing 1, and a third seal ring 9 is disposed in the groove at the left end of the housing 1.

According to the magnetic liquid composite sealing device provided by the embodiment of the invention, the third sealing ring is arranged, so that the sealing property between the shell 1 and the sealing cavity is improved.

The magnetic-fluid composite sealing device according to some specific examples of the present invention is described below with reference to fig. 1 and 2.

The magnetic liquid composite sealing device provided by the embodiment of the invention is used for sealing a sealing cavity and comprises a shell 1, a rotating shaft 2, a sealing assembly 3, an adsorption component 4, a first sealing ring 5, a second sealing ring 6, an air supply assembly 7, an end cover 8 and a third sealing ring 9.

The housing 1 has a chamber 101 therein.

The rotary shaft 2 is horizontally and rotatably provided in the chamber 101 in the left-right direction.

The seal assembly 3 is sleeved on the rotating shaft 2, the seal assembly 3 is located in the cavity 101, the seal assembly 3 comprises a brush seal part 31, a magnetic liquid seal part 32 and a labyrinth seal part 33, the brush seal part 31, the magnetic liquid seal part 32 and the labyrinth seal part 33 are respectively sleeved on the rotating shaft 2, the brush seal part 31, the magnetic liquid seal part 32 and the labyrinth seal part 33 are arranged at intervals in the left-right direction, the brush seal part 31 is located on the leftmost side of the seal assembly 3, the labyrinth seal part 33 is located on the rightmost side of the seal assembly 3, and the magnetic liquid seal part 32 is arranged between the brush seal part 31 and the labyrinth seal part 33. The magnetic liquid seal member 32 has a seal gap in the vertical direction with the rotating shaft 2, and magnetic liquid is adsorbed in the seal gap.

The inner peripheral surface of the labyrinth seal member 33 is provided with a plurality of projections arranged at intervals in the axial direction of the rotating shaft 2.

The brush seal member 31 includes a first barrier 311, a plurality of brush tufts 312, and a second barrier 313, the first barrier 311, the brush tufts 312, and the second barrier 313 are respectively fitted around the rotating shaft 2, the first barrier 311, the brush tufts 312, and the brush tufts 313 are spaced apart in the left-right direction, and the brush tufts 312 are disposed between the first barrier 311 and the second barrier 313, the first barrier 311 is provided with a plurality of first mounting holes 3111 penetrating the first barrier 311 in the left-right direction, the plurality of first mounting holes 3111 are spaced apart in the up-down direction, the second barrier 313 is provided with a plurality of second mounting holes 3131 penetrating the second barrier 313 in the left-right direction, the plurality of second mounting holes 3131 are spaced apart in the up-down direction, and the plurality of second mounting holes 3131 are disposed in the up-down direction. The number of the first mounting holes 3111 and the number of the second mounting holes 3131 are the same, and the sum of the number of the first mounting holes 3111 and the number of the second mounting holes 3131 is equal to the number of the suction members 4.

The inner peripheral surfaces of the first baffle 311 and the second baffle 313 are respectively provided with a seal tooth, and a preset gap is formed between the seal tooth and the rotating shaft 2 in the radial direction of the rotating shaft 2.

The right end surface of the first barrier 311 is in contact with the left end surface of the brush filament bundle 312, and the left end surface of the second barrier 313 is in contact with the right end surface of the brush filament bundle 312. The sealing teeth on the inner periphery of the first baffle 311 are single teeth, the cross section of the sealing teeth on the inner periphery of the first baffle 311 in the vertical direction is substantially in the shape of an isosceles triangle, the sealing teeth of the second baffle 313 are single teeth, the cross section of the sealing teeth on the inner periphery of the second baffle 313 in the vertical direction is substantially in the shape of a right-angled triangle, one right-angled side of the right-angled triangle is in contact with the right end face of the brush bristle bundle 312, and the other right-angled plate of the right-angled triangle is in contact with the inner peripheral surface of the second baffle 313.

The magnetic liquid sealing component 32 includes a first pole piece 321, a second pole piece 322 and a permanent magnet 323, the first pole piece 321 and the second pole piece 322 are respectively sleeved on the rotating shaft 2, the first pole piece 321 and the second pole piece 322 are arranged at intervals in the left-right direction, the permanent magnet 323 is arranged between the first pole piece 321 and the second pole piece 322, a plurality of first pole teeth 3211 are arranged on the inner circumference of the first pole piece 321, a plurality of first pole teeth 3211 are arranged at intervals in the left-right direction, magnetic liquid is adsorbed between the plurality of first pole teeth 3211 and the rotating shaft 2, a plurality of second pole teeth 3221 are arranged on the inner circumference of the second pole piece 322, a plurality of second pole teeth 3221 are arranged at intervals in the left-right direction, and magnetic liquid is adsorbed between the plurality of second pole teeth 3221 and the rotating shaft 2.

Grooves are formed in the outer peripheral surface of the first pole piece 321 and the outer peripheral surface of the second pole piece 322, the first sealing ring 5 is arranged in the groove of the first pole piece 321, and the second sealing ring 6 is arranged in the groove of the second pole piece 322.

The number of the suction members 4 is plural, and the plural suction members 4 are arranged at intervals in the vertical direction. A plurality of suction members 4 are respectively positioned in the first mounting hole 3111 and the second mounting hole 3131, and the sum of the number of the first mounting hole 3111 and the number of the second mounting hole 3131 is equal to the number of the suction members 4.

Air feed subassembly 7 is located cavity 101, air feed subassembly 7 is located brush seal part 31's left side, air feed subassembly 7 includes fixed plate 71 and a plurality of air feed spare 72, fixed plate 71 cover is established on pivot 2, a plurality of air feed spare 72 are at the interval arrangement in fixed plate 71's circumference, air feed spare 72 is towards sealed chamber air feed, a plurality of air feed spare 72 all link to each other with external power source through the wire, be equipped with through-hole 103 on the casing 1, the wire passes through-hole 103.

The end cover 8 is arranged at the right end of the shell 1, the end cover 8 is connected with the shell 1 through bolts, the rotating shaft 2 penetrates through the end cover 8, and the left end face of the end cover 8 is abutted to the right end face of the labyrinth seal part 33.

The left end of the shell 1 is provided with a groove, and the third sealing ring 9 is arranged in the groove at the left end of the shell 1.

The operation principle of the magnetic-fluid composite sealing device of the embodiment of the present invention is described below with reference to fig. 1 and 2.

After the magnetic liquid composite sealing device of the embodiment of the invention is connected with external equipment, the labyrinth sealing part 33 can reduce the pressure difference between the outside and the sealing cavity, thereby reducing the pressure born by the magnetic liquid seal, improving the high pressure resistance of the magnetic liquid composite sealing device, and simultaneously, the magnetic liquid seal can also meet the vacuum sealing requirement. And the labyrinth seal part 33 can also filter external dust, reduce the amount of the external dust entering the magnetic liquid, keep the magnetic liquid clean, and prolong the service life of the sealing device. The air supply member 72 can supply air to one side of the sealing cavity, so that the sealing medium is not easy to enter the sealing device, the brush type sealing part 31 can also prevent the sealing medium from entering the subsequent sealing device, and the adsorption part 4 can adsorb the sealing medium entering the sealing device.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A magnetic fluid composite seal for sealing a sealed cavity, the magnetic fluid composite seal comprising:

a housing having a chamber therein;

the rotating shaft is rotatably arranged in the cavity;

a seal assembly fitted around the rotating shaft and located in the chamber, the seal assembly including a brush seal member, a magnetic liquid seal member, and a labyrinth seal member fitted around the rotating shaft, respectively, the brush seal member, the magnetic liquid seal member, and the labyrinth seal member being arranged at intervals in an axial direction of the rotating shaft and disposed adjacent to the seal chamber, the magnetic liquid seal member being disposed between the brush seal member and the labyrinth seal member;

and the adsorption part is arranged in the brush type sealing part and is used for adsorbing the sealing medium overflowing from the sealing cavity.

2. The magnetic-fluid composite sealing device according to claim 1, wherein an inner peripheral surface of the labyrinth seal member is provided with a plurality of projections arranged at intervals in an axial direction of the rotating shaft.

3. The magnetic-liquid composite sealing device according to claim 1, wherein the brush type sealing member includes a first baffle, a brush wire bundle, and a second baffle, the first baffle, the brush wire bundle, and the second baffle are respectively fitted around the rotating shaft, the first baffle, the brush wire bundle, and the second baffle are arranged at intervals in the axial direction of the rotating shaft, the brush wire bundle is disposed between the first baffle and the second baffle, the first baffle is provided with a first mounting hole penetrating the first baffle in the axial direction of the rotating shaft, the adsorption member is located in the first mounting hole, the second baffle is provided with a second mounting hole penetrating the second baffle in the axial direction of the rotating shaft, and the adsorption member is located in the second mounting hole.

4. The magnetic-fluid composite sealing device of claim 3, wherein the inner circumferential surfaces of the first baffle and the second baffle are respectively provided with sealing teeth, and a preset gap is formed between the sealing teeth and the rotating shaft in the radial direction of the rotating shaft.

5. The magnetic-liquid composite sealing device according to claim 1, wherein the magnetic-liquid sealing member includes a first pole piece, a second pole piece, and a permanent magnet, the first pole piece and the second pole piece are respectively sleeved on the rotating shaft, the first pole piece and the second pole piece are arranged in an axial direction of the rotating shaft at intervals, the permanent magnet is arranged between the first pole piece and the second pole piece, an inner circumference of the first pole piece is provided with a plurality of first pole teeth, the plurality of first pole teeth are arranged in an axial direction of the rotating shaft at intervals, magnetic liquid is adsorbed between the plurality of first pole teeth and the rotating shaft, an inner circumference of the second pole piece is provided with a plurality of second pole teeth, the plurality of second pole teeth are arranged in an axial direction of the rotating shaft at intervals, and magnetic liquid is adsorbed between the plurality of second pole teeth and the rotating shaft.

6. The magnetic-fluid composite sealing device of claim 5, wherein grooves are formed on the outer peripheral surface of the first pole shoe and the outer peripheral surface of the second pole shoe,

the magnetic liquid composite sealing device further comprises a first sealing ring and a second sealing ring, the first sealing ring is arranged in the groove of the first pole shoe, and the second sealing ring is arranged in the groove of the second pole shoe.

7. The magnetic-fluid composite sealing device according to claim 1, further comprising an air supply assembly, wherein the air supply assembly is located in the chamber, the air supply assembly is disposed on a side adjacent to the brush seal member, and the air supply assembly is located at an end away from the magnetic-fluid seal member, the air supply assembly includes a fixing plate and a plurality of air supply members, the fixing plate is fitted around the rotating shaft, the plurality of air supply members are spaced apart from each other in a circumferential direction of the fixing plate, and the air supply members supply air to the seal chamber.

8. The magnetic-fluid composite sealing device of any one of claims 1-7, further comprising an end cap disposed at one end of the housing, the shaft passing through the end cap.

9. The magnetic fluid composite seal of claim 8, wherein an end of the housing opposite the end cap is provided with a groove, the magnetic fluid composite seal further comprising a third seal ring, the third seal ring being disposed within the groove of the housing.