Air bearing device capable of preventing axial movement

Abstract

The invention relates to the technical field of air bearings, and discloses an air bearing device capable of preventing axial movement, the air bearing device comprises an air supply system, a bearing base body and a rotating roller, a permanent magnet pre-tightening structure and an electromagnetic fine tuning structure are embedded on the inner wall of the bearing base body, and the outer surfaces of the permanent magnet pre-tightening structure and the electromagnetic fine tuning structure are coplanar with the inner wall of the bearing base body; the permanent magnet pre-tightening structure at least comprises two sets of permanent magnets arranged at intervals, the electromagnetic fine tuning structure at least comprises two sets of electromagnetic modules, the electromagnetic modules are located on the outer sides of the corresponding permanent magnets and tightly attached to the corresponding permanent magnets, and the magnetic direction of the electromagnetic modules is opposite to that of the permanent magnets. The thrust disc adopts a gas-magnetic division design, prevents axial movement by utilizing magnetic force, adopts a design of taking permanent magnet as a main part and taking electromagnetism as an auxiliary part, is highly integrated, does not need to occupy additional axial space, is more compact in structure, adapts to small and high-speed main shaft scenes, and is controllable in electromagnetic heating defect compared with a traditional thrust disc structure.

Description

Technical Field

[0001] This invention relates to the field of air bearing technology, and in particular to an air bearing device for preventing axial movement. Background Technology

[0002] Air bearings, as a type of non-contact bearing, rely on an air film formed by gas pressure to support moving parts. They have advantages such as low frictional resistance, low wear, high rotational accuracy, and smooth operation, and have been widely used in high-end fields such as high-speed precision machining, aerospace, and precision measurement. During the operation of air bearings, axial runout is one of the core issues affecting their positioning accuracy and operational stability. Axial runout refers to the reciprocating offset of rotating parts along the axial direction. Once axial runout occurs, it will not only reduce the machining and measurement accuracy of the equipment, but may also lead to air film rupture, component wear, and even equipment failure, thus shortening the service life of the air bearing.

[0003] Existing solutions for axial movement of air bearings mainly focus on the following aspects: First, adopting an external bidirectional opposing thrust air bearing structure, where thrust discs and thrust bearings are arranged at both ends of the rotating components or on the flange face, and forming an opposing air film through bidirectional air supply to achieve axial limiting; Second, using small-orifice throttling or porous graphite throttling methods to improve the axial air film stiffness and reduce the amount of axial movement; Third, adopting a gas static pressure pre-tightening structure, achieving non-contact pre-tightening through the air pressure difference of the bidirectional thrust surfaces to improve axial positioning accuracy; Fourth, reducing movement caused by assembly gaps by strictly controlling the parallelism and flatness of the thrust disc and thrust bearing, and adopting an axial zero-clearance grinding process; Fifth, using air film displacement sensors combined with active control circuits in high-end equipment to adjust the air supply pressure and flow rate in real time to suppress axial movement.

[0004] However, the aforementioned existing technical solutions still have many defects and shortcomings in practical applications, making it difficult to meet the usage requirements of small and micro high-speed spindles and other scenarios with limited axial space. This is because the traditional external bidirectional thrust air bearing structure requires additional thrust discs and thrust bearings to be arranged at both ends of the rotating parts, occupying a large amount of axial space and resulting in a large structural volume. This makes it unsuitable for small and micro high-speed spindles and other equipment with limited axial space. Furthermore, the processing and assembly precision requirements of the thrust disc are extremely high. If the assembly deviation is too large, it will exacerbate axial movement and increase the overall weight and manufacturing cost of the device. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing an air bearing device to prevent axial movement.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An air bearing device for preventing axial movement includes: an air supply system, a bearing base, and a rotating roller. The air supply system provides clean, stable-pressure compressed air to provide the power source for the formation of the air film gap, ensuring the core requirement of non-contact operation of the bearing. The bearing base, as the mounting carrier and support foundation of the entire device, is made of high-strength alloy through precision machining, possessing good rigidity and dimensional stability, and can effectively avoid its own deformation from affecting the axial positioning accuracy. The rotating roller, as a moving part, has a polished surface to reduce airflow disturbance within the air film gap, and its two ends are connected to an external transmission mechanism to achieve high-speed and stable rotation. The inner wall of the bearing base is embedded with a permanent magnet pre-tightening structure and an electromagnetic fine-tuning structure. Both are fixed by an embedded snap-fit ​​method to ensure that the outer surface of the permanent magnet pre-tightening structure and the electromagnetic fine-tuning structure is completely flush with the inner wall of the bearing base, without any protrusions or depressions, so as to avoid interfering with the uniformity of the air film and prevent contact friction with the rotating roller during rotation. The permanent magnet preload structure includes at least two sets of spaced permanent magnets. The permanent magnets are preferably made of neodymium iron boron permanent magnet material, which has high magnetic energy product and strong attraction force. The two sets of permanent magnets are arranged axially along the bearing base, and the spacing is adapted to the length of the male centering part on the rotating roller. The spaced part forms a female centering part, which is a smooth planar structure used to cooperate with the male centering part on the rotating roller to achieve initial axial centering. The magnetic pole directions of the two sets of permanent magnets facing the inner wall of the bearing base are the same, for example, both with the N pole facing outward, to ensure that the two sets of permanent magnets generate a uniform and unidirectional attraction force on the magnetic ring on the rotating roller, providing a stable preload force for the rotating roller and limiting its initial axial displacement. The electromagnetic fine-tuning structure includes at least two sets of electromagnetic modules, each corresponding to a permanent magnet. The electromagnetic modules are located outside the corresponding permanent magnet and are arranged close to the end face of the corresponding permanent magnet. The electromagnetic modules adjust the magnitude of the current through an external control circuit, thereby changing the magnetic strength of the electromagnetic modules. The magnetic direction of the electromagnetic modules is always opposite to that of the permanent magnets. That is, when the permanent magnets face outward as the N pole, the electromagnetic modules face outward as the S pole. By utilizing the attraction force between the permanent magnets and the magnetic ring and the repulsion force between the electromagnetic modules and the magnetic ring to form a balance, precise fine-tuning of the axial position of the rotating roller is achieved. Two magnetic rings are nested at intervals on the rotating roller. The magnetic rings are made of magnetic materials that match the permanent magnets and are nested on the outer wall of the rotating roller by an interference fit. The interval between them forms a male centering part. The length of the male centering part is exactly the same as the length of the female centering part, and the position corresponds one-to-one with the female centering part. A stable magnetic attraction force is generated between the magnetic rings and the permanent magnets to achieve the initial axial positioning of the rotating roller. At the same time, a repulsive force is generated between the magnetic rings and the electromagnetic module, which forms an opposite balance with the magnetic attraction force. When the rotating roller deviates axially, the magnitude of the repulsive force is changed by adjusting the current of the electromagnetic module, and the rotating roller is reset to the preset axial position. The outer surface of the magnetic rings is precision machined to be completely flush with the outer wall of the rotating roller, ensuring that the overall outer wall of the rotating roller is smooth and flat, and ensuring the uniformity of the air film gap. The rotating roller is set inside the bearing base and the two are arranged coaxially. The gap between the rotating roller and the bearing base is the air film gap. After the compressed air supplied by the air supply system enters the air film gap, a uniform and stable high-pressure air film is formed, which realizes non-contact support for the rotating roller.

[0007] As a further embodiment of the present invention, the bearing base is composed of multiple sets of identical bearing blocks spliced ​​together. Each set of bearing blocks is a fan-shaped structure. Each set of permanent magnets and each set of electromagnetic modules contains multiple individual parts. The number of individual parts matches the number of bearing blocks, and the individual parts are staggered with the bearing blocks. That is, each permanent magnet individual and each electromagnetic module individual is connected across the splice of two adjacent bearing blocks.

[0008] As a further aspect of the present invention, each individual component of the permanent magnet and the electromagnetic module is fixedly mounted on the corresponding bearing block. One end of the permanent magnet and the electromagnetic module are designed as a boss structure, which is embedded in the corresponding groove of the adjacent bearing block. This not only enables the permanent magnet and the electromagnetic module to be firmly fixed, but also serves as a positioning reference for the splicing of bearing blocks, assisting in the precise splicing of multiple sets of bearing blocks. This ensures that the inner wall of the bearing base is smooth and the coaxiality meets the standard after splicing, avoiding uneven air film gap due to splicing errors, and thus preventing axial movement of the rotating roller.

[0009] As a further aspect of the present invention, a connecting air passage is provided in the bearing block. The connecting air passage is processed by precision drilling and penetrates the inner wall and both ends of the bearing block. Its inner wall is polished to reduce airflow resistance. The connecting air passage forms a network in the bearing block, and its orientation is evenly distributed along multiple outlets on the inner wall of the bearing block to ensure that compressed air can be evenly delivered to each area of ​​the air film gap, thus providing a guarantee for the stable formation of the air film.

[0010] As a further aspect of the present invention, the permanent magnet pre-tightening structure and the electromagnetic fine-tuning structure are provided with a receiving air passage that matches the connecting air passage. The receiving air passage is coaxially aligned with the connecting air passage to ensure smooth airflow. The outlet of the receiving air passage is set towards the air film gap so that air can enter the receiving air passage through the connecting air passage and then be evenly discharged to the air film gap by the receiving air passage, thus ensuring the uniformity of air supply to the air film.

[0011] As a further aspect of the present invention, the air supply system includes at least an air supply sleeve, which is an overall annular structure and tightly fitted onto the outside of the bearing base. The air supply sleeve is provided with multiple air supply ports, the number of which corresponds one-to-one with the number of bearing blocks. Each air supply port is connected to an independent air supply branch, and a pressure reducing valve and a flow meter are provided on the branch for individually supplying air to multiple bearing blocks. The air supply pressure and flow rate can be precisely adjusted according to the air film gap requirements of different bearing blocks to compensate for the differences in air film thickness caused by splicing errors and ensure that the overall air film is uniform and stable.

[0012] As a further embodiment of the present invention, air guide covers are installed at both ends of the air supply sleeve. The air guide covers are arranged coaxially with the rotating roller. The air guide covers are provided with spiral grooves. The spiral direction of the spiral grooves is consistent with the rotation direction of the rotating roller. They are used to guide the air ejected from the end of the bearing block and the air ejected from the outlet of the air film gap. Through the guiding effect of the spiral grooves, a spiral airflow concave towards the center is formed on the outside of the rotating roller. This airflow can generate centripetal suction, which helps to stabilize the axial position of the rotating roller. At the same time, it carries away the heat generated during the rotation, prevents the bearing base and the rotating roller from axial movement due to thermal deformation, and can also block external dust and other impurities from entering the air film gap, thus protecting the bearing structure.

[0013] As a further aspect of the present invention, the permanent magnet, electromagnetic module, and magnetic ring all adopt a Hellbeck array structure. The Hellbeck array is composed of multiple magnets with different magnetic pole directions. By optimizing the magnetic pole arrangement, the magnetic field strength on one side of the array is significantly enhanced, while the magnetic field strength on the other side is significantly weakened. With this structure, the attraction force of the permanent magnet to the magnetic ring and the repulsion force of the electromagnetic module to the magnetic ring are both improved, and the magnetic field distribution is more uniform. This reduces magnetic field leakage and minimizes interference with the air film airflow and surrounding components. At the same time, the structural characteristics of the Hellbeck array make the axial force on the rotating roller more stable and the fine-tuning response speed faster. This effectively suppresses the axial movement of the rotating roller during high-speed operation and improves the overall operational stability of the bearing device.

[0014] Compared with the prior art, the beneficial effects of the present invention are: This invention employs a pneumatic-magnetic separation design, utilizing magnetic force to prevent axial movement. It uses a permanent magnet as the primary magnet and electromagnetic as a secondary magnet, resulting in a highly integrated device. Compared to traditional thrust plate structures, it requires no additional axial space, making it more compact and suitable for small, high-speed spindle applications. The drawback of electromagnetic heating is also controllable. Specifically, this application uses a dual magnetic positioning structure of permanent magnet pre-tensioning and electromagnetic fine-tuning to achieve dual protection of the axial position of the rotating roller. The permanent magnet pre-tensioning structure provides a stable initial pre-tension force, limiting the initial axial movement of the rotating roller, while the electromagnetic fine-tuning structure can accurately correct axial deviation in real time, ensuring that the rotating roller is always in the preset axial position. Positioning accuracy is significantly improved compared to traditional thrust plate structures. It requires additional axial space, resulting in a more compact structure suitable for small, high-speed spindle applications. The permanent magnet preload structure and electromagnetic fine-tuning structure adopt an embedded snap-fit ​​design, flush with the inner wall of the bearing base. This avoids interference with the uniformity of the air film and prevents contact friction during rotation, reducing component wear and extending the service life of the device. It also avoids the problem of the traditional inner anti-movement structure disrupting the air film flow field, ensuring air film stability. Furthermore, the magnetic ring is flush with the outer wall of the rotating roller, and the permanent magnet and electromagnetic structures are flush with the inner wall of the bearing base, ensuring uniform air film gaps, avoiding airflow turbulence, further improving air film stiffness and stability, and reducing the impact of airflow disturbance on the magnetic field, ensuring the working reliability of the magnetic positioning structure. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of an air bearing device for preventing axial movement proposed in this invention. Figure 2 This is a schematic cross-sectional view of the air supply sleeve of an air bearing device for preventing axial movement proposed in this invention. Figure 3 This is a schematic diagram of the air film gap position of an air bearing device for preventing axial movement proposed in this invention; Figure 4 This is a schematic diagram of the air guide cover of an air bearing device for preventing axial movement proposed in this invention; Figure 5 This is a schematic diagram of the bearing base of an air-bearing device for preventing axial movement proposed in this invention. Figure 6 This is a schematic diagram showing the positions of the permanent magnet preload structure and the electromagnetic fine-tuning structure of an air bearing device for preventing axial movement, as proposed in this invention. Figure 7 This is a schematic diagram of the rotating roller of an air bearing device for preventing axial movement proposed in this invention.

[0016] In the diagram: 100, air supply system; 110, air supply sleeve; 120, air guide hood; 121, spiral groove; 200, bearing base; 210, bearing block; 211, connecting air passage; 220, permanent magnet pre-tightening structure; 221, permanent magnet; 230, electromagnetic fine-tuning structure; 231, electromagnetic module; 240, negative centering part; 250, receiving air passage; 300, rotating roller; 310, magnetic ring; 320, positive centering part; 400, air film gap. Detailed Implementation

[0017] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0018] like Figure 1 and Figure 2 As shown, an air bearing device for preventing axial movement includes: an air supply system 100, a bearing base 200, and a rotating roller 300. The air supply system 100 provides clean, stable-pressure compressed air to provide the power source for the formation of the air film gap 400, ensuring the core requirement of non-contact operation of the bearing. The bearing base 200, as the installation carrier and support foundation of the entire device, is made of high-strength alloy through precision machining, possessing good rigidity and dimensional stability, and can effectively avoid its own deformation from affecting the axial positioning accuracy. The rotating roller 300, as a moving part, has a polished surface to reduce airflow disturbance within the air film gap 400, and its two ends are connected to an external transmission mechanism to achieve high-speed and stable rotation. like Figure 5 As shown, a permanent magnet preload structure 220 and an electromagnetic fine-tuning structure 230 are embedded in the inner wall of the bearing base 200. Both are fixed by an embedded snap-fit ​​method to ensure that the outer surfaces of the permanent magnet preload structure 220 and the electromagnetic fine-tuning structure 230 are completely flush with the inner wall of the bearing base 200, without any protrusions or depressions, so as to avoid interfering with the uniformity of the air film and prevent contact friction with the rotating roller 300 during rotation. like Figure 6 and Figure 7As shown, the permanent magnet preload structure 220 includes at least two sets of spaced permanent magnets 221. The permanent magnets 221 are preferably made of neodymium iron boron permanent magnet material, which has high magnetic energy product and strong attraction force. The two sets of permanent magnets 221 are arranged axially along the bearing base 200, and the spacing is adapted to the length of the male centering part 320 on the rotating roller 300. The spaced part forms a female centering part 240, which is a smooth planar structure and is used to cooperate with the male centering part 320 on the rotating roller 300 to achieve initial axial centering. The magnetic pole directions of the two sets of permanent magnets 221 facing the inner wall of the bearing base 200 are the same, for example, both with the N pole facing outward, to ensure that the two sets of permanent magnets 221 generate a uniform and unidirectional attraction force on the magnetic ring 310 on the rotating roller 300, providing a stable preload force for the rotating roller 300 and limiting its initial axial displacement. like Figure 6 and Figure 7 As shown, the electromagnetic fine-tuning structure 230 includes at least two sets of electromagnetic modules 231, which are arranged one-to-one with the permanent magnets 221. The electromagnetic modules 231 are located on the outside of the corresponding permanent magnets 221 and are arranged close to the end face of the corresponding permanent magnets 221. The electromagnetic modules 231 adjust the magnitude of the current through an external control circuit, thereby changing the magnetic strength of the electromagnetic modules 231. The magnetic direction of the electromagnetic modules 231 is always opposite to the magnetic direction of the permanent magnets 221. That is, when the permanent magnets 221 face outward as the N pole, the electromagnetic modules 231 face outward as the S pole. The attraction force between the permanent magnets 221 and the magnetic rings 310 and the repulsion force between the electromagnetic modules 231 and the magnetic rings 310 are balanced to achieve precise fine-tuning of the axial position of the rotating rollers 300. like Figure 7 As shown, two magnetic rings 310 are nested at intervals on the rotating roller 300. The magnetic rings 310 are made of magnetic material that matches the permanent magnet 221 and are nested on the outer wall of the rotating roller 300 by interference fit. The interval between them forms a male centering part 320. The length of the male centering part 320 is exactly the same as the length of the female centering part 240, and their positions correspond one-to-one with the female centering part 240. A stable magnetic attraction force is generated between the magnetic rings 310 and the permanent magnet 221 to achieve the initial axial positioning of the rotating roller 300. At the same time, a repulsive force is generated between the magnetic rings 310 and the electromagnetic module 231, which forms an opposite balance with the magnetic attraction force. When the rotating roller 300 is axially offset, the magnitude of the repulsive force is changed by adjusting the current of the electromagnetic module 231, and the rotating roller 300 is reset to the preset axial position. The outer surface of the magnetic rings 310 is precision machined and is completely flush with the outer wall of the rotating roller 300 to ensure that the overall outer wall of the rotating roller 300 is smooth and flat, and to ensure the uniformity of the air film gap 400. like Figure 3As shown, the rotating roller 300 is disposed inside the bearing base 200, and the two are arranged coaxially. The gap between the rotating roller 300 and the bearing base 200 is the air film gap 400. After the compressed air supplied by the air supply system 100 enters the air film gap 400, a uniform and stable high-pressure air film is formed, which realizes non-contact support for the rotating roller 300. The beneficial effects of the present invention include at least the following: The dual magnetic positioning structure, which combines permanent magnet pre-tensioning and electromagnetic fine-tuning, provides dual protection for the axial position of the rotating roller 300. The permanent magnet pre-tensioning structure 220 provides a stable initial pre-tensioning force to limit the initial axial movement of the rotating roller 300, while the electromagnetic fine-tuning structure 230 can accurately correct axial offset in real time, ensuring that the rotating roller 300 is always in the preset axial position. The positioning accuracy is significantly improved. Compared with the traditional thrust plate structure, it does not require additional axial space, making the structure more compact and suitable for small, high-speed spindle scenarios. The permanent magnet pre-tightening structure 220 and the electromagnetic fine-tuning structure 230 adopt an embedded snap-fit ​​design, which is flush with the inner wall of the bearing base 200. This avoids interference with the uniformity of the air film and prevents contact friction during rotation, reducing component wear and extending the service life of the device. At the same time, it avoids the problem of the traditional inner anti-movement structure destroying the air film flow field, ensuring the stability of the air film. Furthermore, the magnetic ring 310 is flush with the outer wall of the rotating roller 300, and the permanent magnet and electromagnetic structure are flush with the inner wall of the bearing base 200, ensuring the uniformity of the air film gap 400, avoiding airflow turbulence, further improving the stiffness and stability of the air film, and reducing the impact of airflow disturbance on the magnetic field, ensuring the working reliability of the magnetic positioning structure.

[0019] It is worth noting that in this invention, the rotating shaft is still supported by an air film rather than by magnetic force. The air and magnetic forces are separated, with the magnetic force only used to prevent axial movement. Specifically, a design is adopted with permanent magnets as the main component and electromagnetic forces as the auxiliary component. The permanent magnet pre-tightening structure 220 provides basic centering and passive operation, while the electromagnetic fine-tuning structure 230 only performs damping and fine-tuning. Therefore, overall, this device is neither a fully electromagnetic bearing nor a high-power magnetic bearing, and the heat generation is controllable.

[0020] like Figure 5 and Figure 6 As shown, the bearing base 200 is assembled from multiple sets of identical bearing blocks 210. Each set of bearing blocks 210 has a fan-shaped structure. Each set of permanent magnets 221 and each set of electromagnetic modules 231 contains multiple individual parts. The number of individual parts matches the number of bearing blocks 210, and the individual parts are staggered with the bearing blocks 210. That is, each permanent magnet 221 and each electromagnetic module 231 is connected across the splicing point of two adjacent bearing blocks 210. In this embodiment, the spliced ​​bearing base 200 has a significantly reduced processing difficulty compared to the integral structure. It can effectively control deformation during processing, improve the dimensional accuracy of the bearing base 200, and facilitate assembly and subsequent maintenance, thereby reducing production and maintenance costs. It solves the problems of high processing difficulty and inconvenient maintenance of the integral bearing base 200.

[0021] like Figure 5 and Figure 6 As shown, each individual part of the permanent magnet 221 and the electromagnetic module 231 is fixedly installed on the corresponding bearing block 210. One end of the permanent magnet 221 and the electromagnetic module 231 are designed as a boss structure and are embedded in the corresponding groove of the adjacent bearing block 210. This not only enables the permanent magnet 221 and the electromagnetic module 231 to be firmly fixed, but also serves as a positioning reference for the splicing of the bearing blocks 210. This assists in the precise splicing of multiple sets of bearing blocks 210, ensuring that the inner wall of the bearing base 200 is smooth and the coaxiality meets the standard after splicing. This avoids uneven air film gap 400 due to splicing errors, thereby preventing axial movement of the rotating roller 300. In this embodiment, the permanent magnet 221 and the electromagnetic module 231 can themselves serve as positioning components, so there is no need to add additional positioning components. While fixing the permanent magnet and electromagnetic units, the bearing block 210 is accurately positioned, which simplifies the assembly process, improves assembly efficiency, and reduces assembly costs.

[0022] like Figure 6 As shown, the bearing block 210 is provided with a connecting air passage 211. The connecting air passage 211 is machined by precision drilling and runs through the inner wall and both ends of the bearing block 210. Its inner wall is polished to reduce airflow resistance. The connecting air passage 211 forms a network in the bearing block 210. Its orientation is evenly distributed along multiple outlets on the inner wall of the bearing block 210 to ensure that compressed air can be evenly delivered to each area of ​​the air film gap 400, thus providing a guarantee for the stable formation of the air film. like Figure 6 As shown, the permanent magnet pre-tightening structure 220 and the electromagnetic fine-tuning structure 230 are provided with receiving air passages 250 that match the connecting air passages 211. The receiving air passages 250 and the connecting air passages 211 are coaxially aligned to ensure smooth airflow. The outlet of the receiving air passages 250 is set towards the air film gap 400 so that air can enter the receiving air passages 250 through the connecting air passages 211 and then be evenly discharged from the receiving air passages 250 to the air film gap 400, thus ensuring the uniformity of air film supply. In this embodiment, the receiving air passage 250 and the connecting air passage 211 are coaxially aligned and tightly fitted to ensure smooth airflow and avoid air leakage and airflow turbulence. At the same time, the receiving air passage 250 is evenly distributed, which can evenly deliver compressed air to the air film gap 400, further improving the uniformity and stability of the air film, enhancing the buffering and supporting role of the air film, suppressing the axial movement of the rotating roller 300, and also preventing airflow from accumulating at the joint between the magnet and the bearing base 200, reducing the axial force generated by the pressure difference, and preventing the rotating roller 300 from axially shifting due to the pressure difference.

[0023] like Figure 1 and Figure 2 As shown, the air supply system 100 includes at least an air supply sleeve 110. The air supply sleeve 110 has an overall annular structure and is tightly fitted onto the outside of the bearing base 200. The air supply sleeve 110 is provided with multiple air supply ports, the number of which corresponds one-to-one with the number of bearing blocks 210. Each air supply port is connected to an independent air supply branch, and a pressure reducing valve and a flow meter are provided on the branch for individually supplying air to multiple bearing blocks 210. The air supply pressure and flow rate can be precisely adjusted according to the air film gap 400 requirements of different bearing blocks 210 to compensate for the differences in air film thickness caused by splicing errors and ensure that the overall air film is uniform and stable.

[0024] like Figure 4 As shown, air guide covers 120 are installed at both ends of the air supply sleeve 110. The air guide covers 120 are coaxially arranged with the rotating roller 300. The air guide covers 120 are provided with spiral grooves 121. The spiral direction of the spiral grooves 121 is consistent with the rotation direction of the rotating roller 300. They are used to guide the air ejected from the end of the bearing block 210 and the air ejected from the outlet of the air film gap 400. Through the guiding effect of the spiral grooves 121, a spiral airflow concave towards the center is formed on the outside of the rotating roller 300. This airflow can generate centripetal suction, which helps to stabilize the axial position of the rotating roller 300. At the same time, it carries away the heat generated during the rotation, preventing the bearing base 200 and the rotating roller 300 from axial movement due to thermal deformation. It can also block external dust and other impurities from entering the air film gap 400 and protect the bearing structure.

[0025] The permanent magnet 221, electromagnetic module 231, and magnetic ring 310 all adopt a Hellbeck array structure. The Hellbeck array is composed of multiple magnets with different magnetic pole directions. By optimizing the magnetic pole arrangement, the magnetic field strength on one side of the array is greatly enhanced, while the magnetic field strength on the other side is significantly weakened. With this structure, the attraction force of the permanent magnet 221 to the magnetic ring 310 and the repulsion force of the electromagnetic module 231 to the magnetic ring 310 are both improved, and the magnetic field distribution is more uniform. This can reduce magnetic field leakage and reduce interference to the air film airflow and surrounding components. At the same time, the structural characteristics of the Hellbeck array can make the axial force on the rotating roller 300 more stable and the fine-tuning response speed faster. It can effectively suppress the axial movement of the rotating roller 300 during high-speed operation and improve the overall operating stability of the bearing device.

[0026] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An air bearing device for preventing axial movement, characterized in that, include: Air supply system (100), bearing base (200) and rotating roller (300); The bearing base (200) has a permanent magnet preload structure (220) and an electromagnetic fine-tuning structure (230) embedded on its inner wall. The outer surfaces of the permanent magnet preload structure (220) and the electromagnetic fine-tuning structure (230) are flush with the inner wall of the bearing base (200). The permanent magnet preload structure (220) includes at least two sets of spaced permanent magnets (221), the spaced portion of which is a cathode centering portion (240), and the magnetic poles of the two sets of permanent magnets (221) facing the inner wall of the bearing base (200) are in the same direction. The electromagnetic fine-tuning structure (230) includes at least two sets of electromagnetic modules (231). The electromagnetic modules (231) are located outside the corresponding permanent magnet (221) and are in close contact with the corresponding permanent magnet (221). The magnetic direction of the electromagnetic modules (231) is opposite to the magnetic direction of the permanent magnet (221). The rotating roller (300) has two magnetic rings (310) nested at intervals, with the spacer portion being a male centering part (320). The length and position of the male centering part (320) and the female centering part (240) are corresponding. The magnetic ring (310) is attracted to the permanent magnet (221) and repelled by the electromagnetic module (231). The outer surface of the magnetic ring (310) is flush with the outer wall of the rotating roller (300). The rotating roller (300) is disposed inside the bearing base (200), and the gap between the rotating roller (300) and the bearing base (200) is the air film gap (400).

2. The air bearing device for preventing axial movement according to claim 1, characterized in that, The bearing base (200) is assembled from multiple sets of identical bearing blocks (210). Each set of permanent magnets (221) and each set of electromagnetic modules (231) contains multiple individual parts, which are offset from the bearing blocks (210).

3. The air bearing device for preventing axial movement according to claim 2, characterized in that, Each individual component of the permanent magnet (221) and the electromagnetic module (231) is installed on the corresponding bearing block (210), with one end embedded in the adjacent bearing block (210) to assist in the precise splicing of multiple sets of bearing blocks (210).

4. The air bearing device for preventing axial movement according to claim 2, characterized in that, The bearing block (210) is provided with a connecting air passage (211), which penetrates the inner wall and both ends of the bearing block (210).

5. The air bearing device for preventing axial movement according to claim 4, characterized in that, The permanent magnet pre-tightening structure (220) and the electromagnetic fine-tuning structure (230) are provided with receiving air passages (250) that match the connecting air passages (211), so that air can enter the receiving air passages (250) through the connecting air passages (211) and be discharged.

6. The air bearing device for preventing axial movement according to claim 2, characterized in that, The air supply system (100) includes at least an air supply sleeve (110), which is fitted onto the outside of the bearing base (200) and has multiple air supply ports for individually supplying air to multiple bearing blocks (210).

7. The air bearing device for preventing axial movement according to claim 6, characterized in that, Both ends of the air supply sleeve (110) are equipped with air guide covers (120), and the air guide covers (120) are provided with spiral grooves (121) to guide the air ejected from the end of the bearing block (210) and the air ejected from the outlet of the air film gap (400) to form a spiral airflow that is concave towards the center on the outside of the rotating roller (300) through the spiral grooves (121).

8. The air bearing device for preventing axial movement according to claim 1, characterized in that, The permanent magnet (221), electromagnetic module (231) and magnetic ring (310) all adopt the structure of Heilbeck array.

Images