A magnetic fluid sealing device

Abstract

The present invention discloses a magnetic fluid sealing device, comprising a transmission shaft, a magnetic fluid sealing module and a motor module that are separately arranged and plug-in connected, the magnetic fluid sealing module comprising a magnetic fluid fixing seat and a magnetic fluid sealing assembly installed inside the magnetic fluid fixing seat, a buffer member being provided between the magnetic fluid sealing assembly and the magnetic fluid fixing seat, a dust removal sealing buffer space being formed between the buffer member and the magnetic fluid fixing seat, and an inflation assembly being provided on the magnetic fluid fixing seat that is connected to the dust removal sealing buffer space. The magnetic fluid sealing device has a modular design, and the magnetic fluid sealing module and the motor module can be tested and maintained separately, thus avoiding the problem of low overall disassembly and maintenance efficiency. The design of the dustproof sealing buffer space effectively prevents the influence of external dust on the magnetic fluid assembly, greatly improving the performance of the magnetic fluid sealing assembly and extending the service life of the magnetic fluid sealing device.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic fluid sealing, in particular to a magnetic fluid sealing device. Background Art

[0002] The function of a magnetic fluid seal is to transmit rotational motion to a vacuum-sealed container. When magnetic fluid is injected into the gap in the magnetic field, it fills the entire gap, forming a "liquid O-ring seal." Stability is a prerequisite for the various properties of magnetic fluid. In addition to the inherent factors affecting magnetic fluid stability, such as particle strength, surfactants, carrier fluid, and their proper proportions, the operating environment is also a key external factor influencing magnetic fluid seals. The presence of dust in magnetic fluid seal components can affect their sealing performance, thereby reducing the performance and service life of the magnetic fluid seal.

[0003] Existing magnetic fluid sealing devices typically use oil seals for dust protection, which are particularly susceptible to aging and wear when used on high-temperature, high-speed equipment. Because the oil seal is located on the vacuum side, the entire magnetic fluid sealing device must be disassembled from the equipment for replacement, which is inconvenient to shut down for maintenance. As a result, the performance and service life of most current magnetic fluid sealing devices cannot be improved. Therefore, to address these issues, there is an urgent need to design a magnetic fluid sealing device with dustproof sealing functions. While improving its performance and service life, it is also necessary to facilitate maintenance of the magnetic fluid sealing device and ensure that the strong and weak currents of the magnetic fluid sealing device do not interfere with each other, thereby extending its service life. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems that the existing magnetic fluid sealing devices have limited sealing performance and service life due to the lack of dustproof sealing function, and the overall structure of the equipment brings great inconvenience to maintenance and low maintenance efficiency. The present invention provides a magnetic fluid sealing device with good dustproof sealing function, good performance, reasonable overall structural design, easy maintenance and long service life.

[0005] The technical solution adopted by the present invention to achieve its first invention object is: a magnetic fluid sealing device, including a transmission shaft, and also including a magnetic fluid sealing module and a motor module that are separately arranged and plug-in connected, the magnetic fluid sealing module including a magnetic fluid fixing seat and a magnetic fluid sealing assembly installed inside the magnetic fluid fixing seat, a buffer member is provided between the magnetic fluid sealing assembly and the magnetic fluid fixing seat, a dust removal sealing buffer space is formed between the buffer member and the magnetic fluid fixing seat, and an inflation assembly connected to the dust removal sealing buffer space is provided on the magnetic fluid fixing seat. The magnetic fluid sealing device is modularized by designing the magnetic fluid sealing assembly and the motor. When in use, it only needs to plug-in connect and fix the magnetic fluid sealing module and the motor module through a plug-in connection to be quickly assembled. During on-site installation, they can be installed separately, which is flexible and convenient. Moreover, when the magnetic fluid sealing device subsequently fails and needs maintenance, the magnetic fluid sealing module and the motor module can be tested and maintained separately, avoiding the problem of low overall disassembly and maintenance efficiency. In order to achieve dust-proof sealing of the magnetic fluid sealing device itself, a buffer part is provided between the magnetic fluid component and the magnetic fluid fixing seat, and a dust removal sealing buffer space is formed between the buffer part and the magnetic fluid fixing seat. The dust removal buffer space is used to achieve dust-proof sealing of the magnetic fluid component. Specifically, air is blown into the dust-proof sealing buffer space through the inflation component, and impurities and dust in the dust-proof sealing buffer space are discharged by the action of air pressure. After the internal impurities are removed, a clean protective space is formed inside the dust-proof sealing buffer space. Since the magnetic fluid fixing seat is sealed and connected to the vacuum cavity on the vacuum side, and since the inflation component is closed, the dust-proof sealing buffer space and the vacuum environment inside the vacuum cavity form a relatively sealed space. During the operation of the magnetic fluid sealing device, dust will not enter the dust-proof sealing buffer space during the operation of the device, thereby effectively preventing the influence of external dust on the magnetic fluid component, greatly improving the performance of the magnetic fluid sealing component, improving the overall dust-proof sealing performance of the magnetic fluid sealing device, and having a longer service life.

[0006] Preferably, the dust removal seal buffer space includes a radial buffer space and an axial buffer space, wherein the radial buffer space is arranged in a multi-channel labyrinth structure, and the axial buffer space is arranged in a labyrinth structure. In order to achieve dustproof sealing of the magnetic fluid sealing device in both radial and axial directions, the dustproof seal buffer space is provided with a radial buffer space and an axial buffer space, wherein the radial buffer space is arranged in a multi-channel labyrinth structure, and the axial buffer space is arranged in a labyrinth structure. Such a structure is designed to effectively block dust, thereby ensuring the sealing performance and sealing effect of the magnetic fluid.

[0007] Preferably, the radial buffer space and the transmission shaft cooperate, and the axial buffer space and the inner wall of the magnetic fluid fixing seat cooperate, respectively, with protective gas to form a positive pressure ring to prevent dust from the vacuum side from entering the sealing area. In order to further enhance the dustproof sealing effect and prevent dust particles generated on the vacuum side from entering the magnetic fluid sealing component and affecting its sealing effect during the operation of the equipment, a certain amount of protective gas, such as nitrogen, is continuously blown into the dustproof sealing buffer space through the inflation component, and a positive pressure ring is formed at the radial buffer space and the transmission shaft cooperate, and at the axial buffer space and the inner wall of the magnetic fluid fixing seat cooperate, thereby blocking dust particles on the vacuum side from entering the magnetic fluid sealing component and improving the sealing effect of the magnetic fluid.

[0008] Preferably, the radial buffer space is formed by a labyrinth-like annular groove on the inner wall of the magnetic fluid retainer, a buffer structure provided axially along the buffer element, and a multi-step boss structure on the drive shaft. The design of the radial buffer space structure can form a multi-channel labyrinthine structure, thereby enhancing the dustproof sealing effect.

[0009] Preferably, the axial buffer space is formed by the radial inner wall of the magnetic fluid holder and a plurality of buffer grooves arranged radially along the buffer element. The design of the axial buffer space structure also enhances the dustproof sealing effect of the magnetic fluid seal, effectively blocking dust from entering the magnetic fluid assembly and improving the performance of the magnetic fluid seal.

[0010] Preferably, the magnetic fluid fixing seat is provided with a buffer chamber, a magnetic fluid sealing chamber and a bearing mounting chamber in sequence from the vacuum side to the atmosphere side, the diameter of the buffer chamber is smaller than the diameter of the magnetic fluid sealing chamber, a magnetic fluid positioning convex ring is formed between the buffer chamber and the magnetic fluid sealing chamber, and the magnetic fluid sealing chamber and the bearing mounting chamber are provided with the same diameter. The magnetic fluid fixing seat is mainly used to form a dustproof buffer sealing space, fix the magnetic fluid assembly, the transmission shaft and other components, therefore, the buffer chamber, the magnetic fluid sealing chamber and the bearing mounting chamber are provided in sequence on the magnetic fluid fixing seat, and a magnetic fluid positioning convex ring is formed between the buffer chamber and the magnetic fluid waist belt sealing chamber to realize the positioning of the magnetic fluid assembly at one end on the vacuum side, while the magnetic fluid assembly is limited by the transmission bearing at one end on the atmosphere side, the magnetic fluid sealing chamber and the bearing mounting chamber are provided with the same diameter to facilitate installation and positioning, and also facilitate the coaxiality with the transmission seal of the transmission shaft, thereby realizing the sealing between the magnetic fluid assembly and the transmission shaft, and realizing the transmission connection between the transmission bearing and the transmission shaft.

[0011] Preferably, the labyrinth groove is disposed on the inner wall of the end portion of the buffer chamber facing the vacuum side; the buffer member is disposed within the buffer chamber, comprising an integral axial buffer ring and a radial buffer ring, the axial buffer ring being mated with the labyrinth groove; and the buffer grooves being uniformly distributed on the outer annular surface of the radial buffer ring. The buffer member is structurally configured to, firstly, provide protection and shielding for the magnetic fluid assembly, and secondly, to form a dust-proof, sealed buffer space with the magnetic fluid holder. Therefore, the buffer member is provided with an axial buffer ring and a radial buffer ring, respectively forming an axial buffer space and a radial buffer space.

[0012] Preferably, the multi-step boss structure is provided on the outer circumference of the end of the transmission shaft facing the vacuum side. To form a radial buffer space of a multi-channel labyrinth structure and enhance the dustproof sealing effect, while the radial buffer space is formed by the cooperation between the buffer member and the magnetic fluid holder, the multi-step boss structure is also provided on the transmission shaft to form a radial buffer space between the multi-step boss structure and the magnetic fluid holder, thereby forming a multi-channel labyrinth structure as a whole.

[0013] Preferably, an air inlet channel connected to the dust-proof seal buffer space is provided on the magnetic fluid fixing seat where the dust-proof seal buffer space is located, and the inflation component is sealed and connected to the air inlet of the air inlet channel. In order to achieve air blowing into the dust-proof seal buffer space, an air inlet channel is provided on the magnetic fluid fixing seat where the dust-proof seal buffer space is located, and the inflation component is arranged at the air inlet of the air inlet channel. When air needs to be blown into the dust-proof seal buffer space, the inflation component is opened, and the gas enters the dust-proof seal buffer space through the air inlet channel, and the internal dust is discharged outward through the channel between the dust-proof seal buffer space and the transmission shaft, thereby maintaining a high cleanliness level inside the dust-proof seal buffer space and preventing dust from entering the magnetic fluid component, thereby affecting the sealing performance of the magnetic fluid component.

[0014] Preferably, a plurality of heat dissipation fins are evenly distributed axially on the outer circumference of the magnetic fluid fixing seat, an annular plug-in protrusion is provided at one end of the magnetic fluid fixing seat connected to the motor module, and a corresponding plug-in groove is provided at one end of the motor module connected to the magnetic fluid fixing seat. Since the magnetic fluid sealing device generates a certain amount of heat during operation, which will affect the sealing performance of the magnetic fluid component under high temperature conditions, a plurality of heat dissipation fins are provided on the magnetic fluid fixing seat to achieve rapid heat dissipation and improve the magnetic fluid sealing performance. The annular plug-in protrusion is provided on the magnetic fluid fixing seat, and the plug-in groove is provided on the motor module to facilitate the plug-in connection between the magnetic fluid sealing module and the motor module, and to ensure the coaxiality and verticality between the two modules installed separately, thereby ensuring the stability of the magnetic fluid sealing device during operation.

[0015] Preferably, the motor module includes a motor mounting base, a motor assembly, an encoder assembly and a frequency converter execution unit, wherein the motor mounting base is internally provided with a motor assembly mounting cavity and an encoder assembly mounting cavity, the motor assembly mounting cavity is arranged toward one end of the vacuum side, and the encoder assembly mounting cavity is arranged toward one end of the atmosphere side, the motor assembly is arranged inside the motor assembly mounting cavity, the encoder assembly is arranged inside the encoder assembly mounting cavity, and the frequency converter execution unit is used to compare the speed data of the motor assembly with a set value and adjust the speed of the motor based on the comparison value. The above structure of the motor module is to provide power to the magnetic fluid sealing module. Based on this, this combined modular motor setting can meet the design requirements of motors of different sizes and models, and thus meet the assembly needs of magnetic fluid sealing devices of different specifications and models, thereby improving the application range and versatility of the magnetic fluid sealing device.

[0016] Preferably, the motor mounting base is provided with a strong current line slot and a weak current line slot, and the motor assembly includes a frameless direct drive motor, a motor rotor positioning sleeve, and a motor stator positioning gland; the motor rotor positioning sleeve is sleeved on the drive shaft, the frameless direct drive motor is arranged on the outer circumference of the motor rotor positioning sleeve, and cooperates with the motor assembly mounting cavity, and the motor stator positioning gland is pressed on one end of the motor stator facing the magnetic fluid sealing module. Since the magnetic fluid sealing device is used to transmit the rotational motion of the atmospheric side to the vacuum side, it is generally required to have good performance, especially to avoid mutual interference between strong and weak currents, so as to ensure the overall performance of the motor is good. Therefore, in order to avoid mutual interference between strong and weak currents, a strong current line slot and a weak current line slot are respectively provided on the motor mounting base, so that the strong and weak wires are arranged separately, and the strong and weak currents do not interfere with each other.

[0017] Preferably, the encoder assembly includes an encoder disc locator, an encoder, and an encoder static and dynamic locator. The encoder disc locator is mounted on the drive shaft where the encoder mounting cavity is located, and the encoder static and dynamic locator is connected to the motor mounting base via locking screws. The encoder is mounted on the encoder disc locator and connected to the static and dynamic locator. A gap adjustment piece is provided between the static and dynamic locator and the motor mounting base. The encoder is used to detect the speed data of the drive shaft and transmit the speed data to the inverter actuator. The inverter actuator compares the speed data with a set value and adjusts the motor speed based on the comparison value to meet the requirements of different speed transmissions.

[0018] The beneficial effects of the present invention are as follows: the magnetic fluid sealing device, through the modular design of the magnetic fluid sealing assembly and the motor, can be installed separately, providing a flexible and convenient installation method. The magnetic fluid sealing module and the motor module can be tested and maintained separately, avoiding the problem of inefficient overall disassembly and maintenance. The design of the dustproof seal buffer space effectively prevents the influence of external dust on the magnetic fluid assembly, greatly improving the performance of the magnetic fluid sealing assembly and extending the service life of the magnetic fluid sealing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural schematic diagram of the magnetic fluid sealing device of the present invention;

[0020] Figure 2 yes Figure 1 Enlarged view of point A in the middle;

[0021] Figure 3 This is a structural diagram of a magnetic fluid fixing seat in the present invention;

[0022] Figure 4 This is a structural diagram of the magnetic fluid sealing module of the present invention;

[0023] Figure 5 yes Figure 4 Enlarged view of point B in the middle;

[0024] Figure 6 This is a structural diagram of the motor module in the present invention;

[0025] Figure 7 This is a structural diagram of the motor fixing base in the present invention;

[0026] Figure 8 yes Figure 7 Left side view of the middle motor mounting base;

[0027] Figure 9 This is a structural diagram of Example 3 of the present invention;

[0028] In the figure: 1, transmission shaft, 100, multi-step boss structure;

[0029] 2. Magnetic fluid sealing module;

[0030] 3. Motor module, 31. Motor fixing seat, 310. Motor assembly installation cavity, 311. Encoder assembly installation cavity, 312. Strong wire trough, 313. Weak wire trough, 32. Motor assembly, 320. Frameless direct drive motor, 321. Motor rotor positioning sleeve, 322. Motor stator positioning cover, 33. Encoder assembly, 330. Encoder dynamic disk positioning seat, 331. Encoder, 332. Encoder dynamic and static positioning seats, 333. Gap adjustment piece;

[0031] 4. Card insertion protrusion, 5. Card insertion groove;

[0032] 6. Magnetic fluid fixing seat, 60. Labyrinth ring groove, 61. Buffer chamber, 62. Magnetic fluid sealing chamber, 63. Bearing mounting chamber, 64. Magnetic fluid positioning convex ring, 65. Fixing seat body, 66. Vacuum connector, 67. Motor connector, 68. Heat dissipation fins;

[0033] 7. Magnetic fluid sealing assembly, 71. Magnetic fluid, 72. Magnetic block, 73. Magnetic fluid, 74. Magnetic teeth;

[0034] 8. Buffer member, 80. Buffer structure, 81. Buffer groove, 82. Axial buffer ring, 83. Radial buffer ring;

[0035] 9. Dust removal and sealing buffer space, 10. Inflatable components;

[0036] 11. Bearing assembly, 110. Bearing, 111. Locking ring;

[0037] 12. Radial buffer space, 121. First channel, 122. Second channel, 123. Third channel, 124. Fourth channel, 125. Fifth channel;

[0038] 13. Axial buffer space, 14. Sealing protective grease, 15. Air intake channel, 16. Spacer ring, 17. Bearing cover. DETAILED DESCRIPTION

[0039] The various aspects of the present invention are described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0040] Example 1:

[0041] exist Figure 1 、 Figure 2 In the embodiment shown, a magnetic fluid sealing device includes a transmission shaft 1, a magnetic fluid sealing module 2 and a motor module 3 which are arranged separately. The magnetic fluid sealing module 2 and the motor module 3 are fixedly connected by an inserting card structure and can be disassembled; the magnetic fluid sealing module 2 is arranged toward the vacuum side, and the motor module 3 is arranged toward the atmosphere side. The inserting card structure includes an inserting card protrusion 4 arranged on the magnetic fluid sealing module and an inserting card groove 5 arranged on the motor module. The magnetic fluid sealing module and the motor module are both arranged in a split type and can be installed separately, making the installation method more flexible and convenient; and when a problem occurs in the device and needs to be repaired, they can be tested and repaired separately, without the need to disassemble the entire device, thereby improving the maintenance efficiency. The inserting card protrusion 4 and the inserting card groove 5 cooperate to ensure the coaxiality and verticality of the device, thereby ensuring the stability of the product during operation.

[0042] like Figure 4As shown, the magnetic fluid sealing module 2 includes a magnetic fluid fixing seat 6 and a magnetic fluid sealing component 7 installed inside the magnetic fluid fixing seat 6. A buffer member 8 is provided between the magnetic fluid sealing component 7 and the magnetic fluid fixing seat 6. A dust removal sealing buffer space 9 is formed between the buffer member 8 and the magnetic fluid fixing seat 6. An inflation component 10 connected to the dust removal sealing buffer space 9 is provided on the magnetic fluid fixing seat 6. An air inlet channel 15 connected to the dust removal sealing buffer space 9 is opened on the magnetic fluid fixing seat 6 where the dust removal sealing buffer space 9 is located. The inflation component 10 is sealed and connected to the air inlet of the air inlet channel 15.

[0043] The dust removal seal buffer space 9 includes a radial buffer space 12 and an axial buffer space 13. The radial buffer space 12 is arranged in a multi-channel labyrinth structure, and the axial buffer space 13 is arranged in a labyrinth structure. The magnetic fluid seal module 2 also includes a bearing assembly 11.

[0044] The radial buffer space 12 is formed by the labyrinthine annular groove 60 arranged on the inner wall of the end of the magnetic fluid fixing seat 6, the buffer structure 80 arranged in the axial direction of the buffer member 8, and the multi-step boss structure 100 on the transmission shaft 1; the axial buffer space 13 is formed by the radial inner wall of the magnetic fluid fixing seat 6 and a plurality of buffer grooves 81 arranged in the radial direction of the buffer member 8.

[0045] like Figure 3 As shown, a buffer chamber 61, a magnetic fluid sealing chamber 62 and a bearing mounting chamber 63 are sequentially provided inside the magnetic fluid fixing seat 6 from the vacuum side to the atmosphere side. The cavity diameter of the buffer chamber 61 is smaller than the cavity diameter of the magnetic fluid sealing chamber 62. A magnetic fluid positioning convex ring 64 is formed between the buffer chamber 61 and the magnetic fluid sealing chamber 62 to limit the magnetic fluid sealing assembly 7 in the axial direction and toward one end of the vacuum side. The magnetic fluid sealing chamber 62 and the bearing mounting chamber 63 are set with the same cavity diameter.

[0046] The labyrinth ring groove 60 is arranged on the inner wall of the end of the buffer cavity 61 facing the vacuum side; the buffer part 8 is arranged inside the buffer cavity 61, and the buffer part 8 includes an axial buffer ring 82 and a radial buffer ring 83 arranged in an integrated manner. The end face of the axial buffer ring 82 forms a buffer structure 80, and is arranged in a plug-in manner with the labyrinth ring groove 60; the buffer grooves 81 are evenly distributed on the outer ring surface of the radial buffer ring 83, and the buffer grooves are arranged in a serrated structure; the multi-step boss structure 100 is arranged on the outer circumference of the end of the transmission shaft 1 facing the vacuum side.

[0047] The multi-stepped boss structure 100, the axial buffer ring 82, and the labyrinth groove 60 cooperate to form a radial buffer space 83 having a multi-channel labyrinth structure. In this embodiment, the multi-channel labyrinth structure is provided with a first channel 121, a second channel 122, a third channel 123, a fourth channel 124, and a fifth channel 125, which are interconnected from the outside to the inside in radial direction.

[0048] The magnetic fluid fixing seat 6 includes an integrally arranged fixing seat body 65, a vacuum connecting body 66 and a motor connecting body 67. The vacuum connecting body 65 is used to realize the connection positioning with the vacuum side equipment, and the motor connecting body 67 is used to realize the plug-in connection positioning with the motor module 3. Therefore, the annular plug-in protrusion 4 is set on the motor connecting body.

[0049] The air inlet channel 15 is formed on the radial wall of the buffer chamber 61. The inlet of the air inlet channel 15 is located at the transition between the vacuum connector 66 and the fixed seat 65. The inflation assembly 10 is disposed at the inlet of the air inlet channel. In this embodiment, the inflation assembly 10 utilizes an air inlet connector, which is threadedly connected to the inlet of the air inlet channel. The air inlet connector is provided with an air inlet port, which is connected to an external air supply device. The air inlet port is connected to the dust-proof inflation chamber and the multi-channel dust-proof inflation structure through the air inlet channel.

[0050] A plurality of heat dissipation fins 68 are evenly distributed along the axial direction on the outer circumference of the fixing seat body 65. The heat dissipation fins 68 are made of aluminum alloy. The heat dissipation fins 68 are provided to dissipate heat from the magnetic fluid fixing seat 6, thereby increasing the service life of the entire magnetic fluid sealing module.

[0051] The magnetic fluid seal assembly 7 is disposed within the magnetic fluid seal cavity 62 and is end-face-bonded with the magnetic fluid positioning convex ring 64. The bearing assembly 11 is mounted within the bearing mounting cavity 63, and a spacer ring 16 is provided between the bearing assembly 11 and the magnetic fluid seal assembly 7 for position limiting. The end of the bearing assembly 11 facing the atmosphere is locked and fixed by a bearing gland 17 and a locking nut 18. Specifically, a gland mounting groove is recessed in the motor connector 67. The bearing gland is pressed into the gland mounting groove and fixed by bolts. At the same time, a locking nut cooperates with the bearing gland to achieve axial limit fixation of the atmospheric end of the bearing.

[0052] like Figure 5As shown, the magnetic fluid seal assembly 7 includes a magnetic fluid 71 and several magnetic blocks 72 disposed within the magnetic fluid 71. A magnetic fluid 73 is disposed at the end of the magnetic fluid 71 that mates with the drive shaft 1. The magnetic fluid 71 and the magnetic fluid seal chamber 62 are sealed by a seal 73. Several magnetic teeth 74 are disposed on the end surface of the magnetic fluid 71 that mates with the drive shaft 1. Alternatively, several magnetic teeth can be disposed on the drive shaft 1 corresponding to the magnetic fluid 71, and the magnetic fluid 3 is coated on the magnetic teeth 74. In this embodiment, the magnetic teeth 74 are disposed on the drive shaft 1.

[0053] The bearing assembly 11 includes two sets of bearings 110 and a locking ring 111 disposed between the two sets of bearings. The locking ring 111 realizes axial limiting and locking of the inner and outer rings of the two sets of bearings 110 .

[0054] like Figure 6 As shown, the motor module 3 includes a motor mount 31, a motor assembly 32, an encoder assembly 33, and an inverter actuator unit. A card insertion groove 5 is provided on the end surface of the motor mount 31 that mates with the magnetic fluid seal module. This groove 5 engages with the card insertion protrusion 4 on the magnetic fluid mount to achieve a card insertion connection. The magnetic fluid mount 6 is connected to the motor mount 31 via a locking screw.

[0055] By separating the motor mount 31 and the magnetic fluid mount 6, the device can be divided into a magnetic fluid module and a motor module, which can be installed separately, making installation more flexible and convenient. Furthermore, if a problem with the device requires maintenance, each module can be tested and repaired separately, eliminating the need to disassemble the entire device, improving maintenance efficiency. The card insertion protrusion and card insertion groove ensure both coaxiality and verticality of the device and stability during operation.

[0056] like Figure 7 As shown, the motor mounting base 31 is provided with a motor assembly mounting cavity 310 and an encoder assembly mounting cavity 311. The motor assembly mounting cavity 310 is provided toward the vacuum side, and the encoder assembly mounting cavity 311 is provided toward the atmosphere side. Figure 8 As shown, a strong wire trough 312 and a weak wire trough 313 are provided on the motor fixing seat 31. The strong wire trough 312 and the weak wire trough 313 are used to separate strong electricity and weak electricity to avoid interference between strong and weak electricity.

[0057] The motor assembly 32 includes a frameless direct-drive motor 320, a motor rotor positioning sleeve 321, and a motor stator positioning gland 322. The motor rotor positioning sleeve 321 is mounted on the drive shaft 1 and positioned using a key. The motor rotor positioning sleeve 321 can be used to adjust the inner diameter of the motor rotor, thereby accommodating motors of different sizes and models, and has a wide range of applications.

[0058] The frameless direct-drive motor 320 is arranged on the outer circumference of the motor rotor positioning sleeve 321 and cooperates with the motor assembly mounting cavity 311. The motor stator positioning cover 322 is pressed on one end of the motor stator facing the magnetic fluid sealing module. The motor stator positioning cover 322 is used to lock the frameless direct-drive motor 320. The motor stator positioning cover 322 is connected to the motor fixing seat 31 through a locking screw.

[0059] The encoder assembly 33 includes an encoder disc locating seat 330, an encoder 331, an encoder static and dynamic locating seat 332, and a gap adjustment plate 333. The encoder disc locating seat 330 is mounted on the drive shaft 1, where the encoder assembly mounting cavity 311 is located. The encoder static and dynamic locating seat 332 is connected to the motor mounting seat 31 via locking screws. The encoder 331 is mounted on the encoder disc locating seat 330 and connected to the encoder static and dynamic locating seat 332. A gap adjustment plate 333 is provided between the encoder static and dynamic locating seat 332 and the motor mounting seat 31. The encoder assembly 33 is secured and sealed by a cover mounted on the atmospheric side of the motor mounting seat 31. The encoder 31 is used to detect the speed data of the drive shaft 1 and transmit the speed data of the motor assembly to the inverter actuator. The inverter actuator compares the speed data with a set value and adjusts the motor speed based on the comparison value.

[0060] Example 2:

[0061] like Figure 2 、 Figure 5 As shown, the technical solution in this embodiment is basically the same as that in Example 1, except that: the radial buffer space 12 and the transmission shaft 1, and the axial buffer space 13 and the inner wall of the magnetic fluid fixing seat 6 are respectively filled with protective gas to form a positive pressure air ring 14 to prevent dust from the vacuum side from entering the sealing area. In order to further increase the dustproof sealing effect and prevent the dust particles generated on the vacuum side from entering the magnetic fluid sealing component and affecting its sealing effect during the operation of the equipment, a certain amount of protective gas, such as nitrogen, is continuously blown into the dustproof sealing buffer space through the inflation component, and a positive air pressure ring is formed at the radial buffer space and the transmission shaft, and at the axial buffer space and the inner wall of the magnetic fluid fixing seat, thereby blocking dust particles on the vacuum side from entering the magnetic fluid sealing component to enhance the sealing effect of the magnetic fluid. In order to ensure the normal operation of the equipment, the protective gas filled into the dust removal sealing buffer space 9 through the inflation component is generally the same as the gas used on the vacuum side of the equipment according to the production process requirements.

[0062] When the equipment is installed, first blow a certain amount of pressurized gas into the air inlet through the external gas supply equipment. The pressurized gas enters the dust removal seal buffer space through the air inlet channel, and the impurities and dust in the dust removal seal buffer space are discharged by the action of air pressure. After the dust removal is completed, a certain amount of protective gas is continuously filled into the dust removal seal buffer space through the inflation component, and a positive pressure air ring is formed inside the dust removal seal buffer space. The pressure of the protective gas is limited to the formation of the positive pressure air ring. Due to the formation of the positive pressure air ring, during the operation of the magnetic fluid sealing device, the pressure in the dustproof seal buffer space is greater than the internal pressure of the vacuum chamber, so that dust will not enter the dustproof seal buffer space through the vacuum side during the operation of the device, thereby effectively preventing the influence of external dust on the magnetic fluid assembly, greatly improving the performance of the magnetic fluid sealing assembly, improving the overall dustproof sealing performance of the magnetic fluid sealing device, and extending the service life.

[0063] Example 3:

[0064] like Figure 9 As shown, the technical solution of this embodiment is basically the same as that of Example 1, except that: the magnetic fluid sealing assembly 7 includes a magnetic fluid 71 and a plurality of magnetic blocks 72 arranged between the magnetic fluid 71, a magnetic fluid 73 is provided at the end of the magnetic fluid 71 that cooperates with the transmission shaft 1, and the magnetic fluid 71 and the magnetic fluid sealing cavity 62 are sealed by a seal 73. A plurality of magnetic teeth 74 are provided on the end surface of the end of the magnetic fluid 71 that cooperates with the transmission shaft 1.

[0065] The above-mentioned magnetic fluid sealing device is designed as a module by combining the magnetic fluid sealing component and the motor. When in use, it is only necessary to connect and fix the magnetic fluid sealing module and the motor module through a plug-in card connection for rapid assembly. During on-site installation, they can be installed separately, and the installation method is flexible and convenient. Moreover, when the magnetic fluid sealing device subsequently fails and requires maintenance, the magnetic fluid sealing module and the motor module can be tested and maintained separately, thus avoiding the problem of low overall disassembly and maintenance efficiency. The dustproof sealing of the magnetic fluid sealing device itself is achieved. A buffer is provided between the magnetic fluid component and the magnetic fluid fixing seat. A dust-removal sealing buffer space is formed between the buffer and the magnetic fluid fixing seat. The dust-removal buffer space is used to achieve dustproof sealing of the magnetic fluid component, greatly improving the performance of the magnetic fluid sealing component, improving the overall dustproof sealing performance of the magnetic fluid sealing device, and improving the service life.

[0066] It should be noted that the above embodiments are merely illustrative of the principles of the present invention. Various variations and improvements are possible without departing from the scope of the present invention, and all such variations and improvements fall within the scope of the claimed invention. Based on the embodiments described herein, all other embodiments derived by persons of ordinary skill in the art on the basis of the technical solutions of this application without inventive effort shall fall within the scope of protection of the present invention.

Claims

1. A magnetic fluid sealing device, comprising a transmission shaft (1), characterized in that: It also includes a magnetic fluid sealing module (2) and a motor module (3) that are separately arranged and connected by plug-in cards, the magnetic fluid sealing module (2) including a magnetic fluid fixing seat (6) and a magnetic fluid sealing component (7) installed inside the magnetic fluid fixing seat (6), a buffer member (8) is provided between the magnetic fluid sealing component (7) and the magnetic fluid fixing seat (6), a dust removal sealing buffer space (9) is formed between the buffer member (8) and the magnetic fluid fixing seat (6), and an inflation component (10) that is connected to the dust removal sealing buffer space (9) is provided on the magnetic fluid fixing seat (6); The dust removal sealing buffer space includes a radial buffer space and an axial buffer space; the radial buffer space and the transmission shaft cooperate, and the axial buffer space and the inner wall of the magnetic fluid fixing seat cooperate, respectively, and are filled with protective gas to form a positive pressure gas ring; the inside of the magnetic fluid fixing seat is provided with a buffer cavity, a magnetic fluid sealing cavity and a bearing mounting cavity in sequence from the vacuum side to the atmosphere side; the buffer part is provided inside the buffer cavity, and the buffer part includes an axial buffer ring and a radial buffer ring which are integrally provided.

2. The magnetic fluid sealing device according to claim 1, characterized in that: The radial buffer space (12) is arranged in a multi-channel labyrinth structure, and the axial buffer space (13) is arranged in a labyrinth structure.

3. The magnetic fluid sealing device according to claim 2, characterized in that: The radial buffer space (12) is formed by the cooperation of a labyrinth-type annular groove (60) provided on the inner wall of the end of the magnetic fluid fixing seat (6), a buffer structure (80) provided in the axial direction of the buffer member (8), and a multi-step boss structure (100) on the transmission shaft (1); the axial buffer space (13) is formed by the cooperation of the radial inner wall of the magnetic fluid fixing seat (6) and a plurality of buffer grooves (81) provided in the radial direction of the buffer member (8).

4. The magnetic fluid sealing device according to claim 3, characterized in that: The diameter of the buffer cavity (61) is smaller than the diameter of the magnetic fluid sealing cavity (62), a magnetic fluid positioning convex ring (64) is formed between the buffer cavity (61) and the magnetic fluid sealing cavity (62), and the magnetic fluid sealing cavity (62) and the bearing mounting cavity (63) are arranged with the same cavity diameter; the labyrinth annular groove (60) is arranged on the inner wall of the end of the buffer cavity (61) facing the vacuum side; the axial buffer ring (82) and the labyrinth annular groove (60) are arranged in a plug-in manner; the buffer grooves (81) are evenly distributed on the outer ring surface of the radial buffer ring (83); the multi-step boss structure (100) is arranged on the outer circumference of the end of the transmission shaft (1) facing the vacuum side.

5. The magnetic fluid sealing device according to claim 1, characterized in that: An air inlet channel (15) communicating with the dust removal sealing buffer space (9) is provided on the magnetic fluid fixing seat (6) where the dust removal sealing buffer space (9) is located, and the inflation component (10) is sealed and connected to the air inlet of the air inlet channel (15).

6. The magnetic fluid sealing device according to any one of claims 1 to 5, characterized in that: A plurality of heat dissipation fins (68) are evenly distributed along the axial direction on the outer circumference of the magnetic fluid fixing seat (6); an annular plug-in protrusion (4) is provided at one end of the magnetic fluid fixing seat (6) connected to the motor module (3); and a corresponding plug-in groove (5) is provided at one end of the motor module (3) connected to the magnetic fluid fixing seat (6).

7. The magnetic fluid sealing device according to any one of claims 1 to 5, characterized in that: The motor module (3) includes a motor fixing seat (31), a motor assembly (32), an encoder assembly (33) and a frequency converter execution unit. The motor fixing seat (31) is provided with a motor assembly installation cavity (310) and an encoder assembly installation cavity (311). The motor assembly installation cavity (310) is provided toward one end of the vacuum side, and the encoder assembly installation cavity (311) is provided toward one end of the atmosphere side. The motor assembly (32) is provided inside the motor assembly installation cavity (310), and the encoder assembly (33) is provided inside the encoder assembly installation cavity (311). The frequency converter execution unit is used to compare the speed data of the motor assembly (32) with a set value and adjust the speed of the motor based on the comparison value.

8. The magnetic fluid sealing device according to claim 7, characterized in that: The motor fixing seat (31) is provided with a strong wire groove (312) and a weak wire groove (313), and the motor assembly (32) includes a frameless direct drive motor (320), a motor rotor positioning sleeve (321) and a motor stator positioning cover (322); the motor rotor positioning sleeve (321) is sleeved on the transmission shaft (1), the frameless direct drive motor (320) is arranged on the outer circumference of the motor rotor positioning sleeve (321) and matched with the motor assembly installation cavity (310), and the motor stator positioning cover (322) is pressed on one end of the motor stator facing the magnetic fluid sealing module (2).

9. The magnetic fluid sealing device according to claim 7, characterized in that: The encoder assembly (33) comprises an encoder moving disc positioning seat (330), an encoder (331) and an encoder dynamic and static positioning seat (332), wherein the encoder moving disc positioning seat (330) is sleeved on the transmission shaft (1) where the encoder assembly mounting cavity (311) is located, and the encoder dynamic and static positioning seat (332) is connected to the motor fixing seat (31) via a locking screw; the encoder (331) is mounted on the encoder moving disc positioning seat (330) and connected to the encoder dynamic and static positioning seat (332), and a gap adjustment piece (333) is provided between the encoder dynamic and static positioning seat (332) and the motor fixing seat (31).

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