Magnetic suspension device and magnetic suspension turntable

Abstract

Disclosed in the present invention are a magnetic suspension device and a magnetic suspension turntable. The magnetic suspension device comprises a stator and a rotor, wherein the stator comprises a permanent magnet device and a first suspension control assembly, the first suspension control assembly comprising a first control assembly and a second control assembly, the first control assembly being configured to apply an axial upward suspension force to the rotor, the second control assembly being configured to apply an axial downward suspension force to the rotor, the first control assembly comprising a plurality of first stator magnetic poles, and the second control assembly comprising a plurality of second stator magnetic poles; and the permanent magnet device comprises a plurality of permanent magnet assemblies, wherein the plurality of permanent magnet assemblies are uniformly arranged in a circumferential direction, an equal or nearly equal magnetic flux is generated at a first air gap of two radially symmetrical first stator magnetic poles in each pair or at a first air gap of each first stator magnetic pole, and an equal or nearly equal magnetic flux is generated at a second air gap of two radially symmetrical second stator magnetic poles in each pair or at a second air gap of each second stator magnetic pole. The present invention can improve the stability of rotation of the magnetic suspension turntable.

Description

Magnetic levitation device and magnetic levitation turntable Technical Field

[0001] The present invention relates to the field of magnetic levitation technology, in particular to a magnetic levitation device and a magnetic levitation turntable. Background Art

[0002] A magnetic levitation device is a type of rotary drive that utilizes magnetic field forces to levitate the rotor, eliminating any mechanical contact between the rotor and stator. Magnetic levitation devices, or rotary drives, offer high cleanliness, no precipitation, no particles, and no dynamic seals, resulting in superior performance. These devices hold promising applications in ultra-pure drive applications such as biochemistry, medicine, and semiconductor manufacturing.

[0003] In semiconductor manufacturing, wafer cleanliness is crucial, as wafer surface cleanliness impacts subsequent semiconductor processing and product yield. To achieve ultra-clean wafers, silicon or other semiconductor materials must be processed in a controlled, ultra-clean atmosphere. For example, one manufacturing step in wafer fabrication is annealing the wafer after ion implantation. Doping imposes strain on the crystal structure. If this stress is not rapidly released, it can lead to undesirable changes in the resistivity of the ion implant. Currently, rapid thermal processing (RT) is commonly used for annealing. Furthermore, wafer processing uniformity is crucial. To achieve this uniformity, wafers are typically rotated around a vertical axis (or z-axis) around their center during processing. Rotation is also used in other wafer processing techniques, such as chemical vapor deposition, thermal treatment, ion implantation, and other doping techniques. To meet the stringent requirements for ultra-cleanliness and processing uniformity in semiconductor manufacturing, semiconductor thermal processing equipment optimally utilizes a magnetically levitated turntable with a contactless rotational drive. A magnetic levitation turntable consists of a stator and rotor, the components of the magnetic levitation mechanism, as well as a wafer carrier. The stator generates a magnetic field to drive the rotor and carrier for rotation and levitation. Depending on the relative position of the stator and rotor, magnetic levitation turntables can be categorized as either inner-rotor or outer-rotor magnetic levitation turntables.

[0004] For example, a magnetic levitation device includes a rotor and a stator. The stator includes a first suspension control assembly (corresponding to the first layer of the rotor) and a second suspension control assembly (corresponding to the second layer of the rotor). The first suspension control assembly includes a first control assembly and a second control assembly. The stator magnetic poles are equally divided in the circumferential direction. For example, the first control assembly includes three first stator magnetic poles equidistantly spaced around the circumference, with winding slots formed between the three first stator magnetic poles. Each first stator magnetic pole is provided with a first electromagnetic winding. The stator also includes a permanent magnet that provides a permanent magnetic bias magnetic field. The permanent magnet is annular and applies a permanent magnetic bias magnetic field to the rotor through the first and second layers of stator magnetic poles. However, for magnetic levitation devices with larger diameters, such as inner rotor magnetic levitation devices, the process for manufacturing large-diameter annular permanent magnets is very difficult and the processing and manufacturing costs are high. In addition, due to the strong permanent magnetic bias magnetic field provided by the permanent magnets, the monolithic structure is difficult to assemble. Therefore, it is necessary to consider using discrete permanent magnets, for example, placing permanent magnets at four equidistant locations (X+, X-, Y+, and Y-) on the circumference. This structure results in the permanent magnetic bias magnetic field (magnetic flux) generated by the multiple permanent magnets being unequal (unbalanced) at the air gaps of the multiple first stator poles of the first suspension control assembly, and also unequal (unbalanced) at the air gaps of the multiple second stator poles. This results in unequal forces exerted by the stator on the rotor at each air gap of the multiple first stator poles, resulting in non-zero combined forces on the x- and y-axes, and unequal z-axis forces at each air gap. Similarly, unequal forces exerted by the stator on the rotor at each air gap of the multiple second stator poles, resulting in non-zero combined forces on the x- and y-axes, and unequal z-axis forces at each air gap. Consequently, even when the rotor rotates in its equilibrium position, it will be subject to unbalanced forces exerted by the permanent magnetic bias magnetic field, causing radial and axial fluctuations in the rotor's operation, affecting the stability of the motor.

[0005] Summary of the Invention

[0006] In order to overcome the defects in the prior art, an embodiment of the present invention provides a magnetic levitation device and a magnetic levitation turntable, which are used to solve at least one of the above problems.

[0007] An embodiment of the present disclosure discloses a magnetic levitation device, including a stator and a rotor, wherein the stator includes a permanent magnet device and a first suspension control component, wherein the first suspension control component includes a first control component and a second control component arranged in an axially staggered manner, wherein the first control component is configured to apply an axially upward suspension force to the rotor, and the second control component is configured to apply an axially downward suspension force to the rotor, characterized in that the first control component includes a plurality of first stator poles, which are uniformly arranged in the circumferential direction, and the second control component includes a plurality of second stator poles, which are uniformly arranged in the circumferential direction; the permanent magnet device includes a plurality of permanent magnet components, which are uniformly arranged in the circumferential direction and generate equal or nearly equal magnetic flux at the first air gap of each pair of radially symmetrical two first stator poles or the first air gap of each first stator pole, and generate equal or nearly equal magnetic flux at the second air gap of each pair of radially symmetrical two second stator poles or the second air gap of each second stator pole.

[0008] Furthermore, the number of the multiple first stator poles, the number of the multiple second stator poles, and the number of the multiple permanent magnet components are all even numbers greater than or equal to 2, or the number of the multiple first stator poles, the number of the multiple second stator poles, and the number of the multiple permanent magnet components are all the same and not an even number.

[0009] Furthermore, the number of the plurality of first stator poles is the same as the number of the plurality of second stator poles and both are even numbers.

[0010] Furthermore, in the circumferential direction, a second stator magnetic pole is arranged between two adjacent first stator magnetic poles, and a first stator magnetic pole is arranged between two adjacent second stator magnetic poles.

[0011] Furthermore, the number of the multiple first stator poles, the number of the multiple second stator poles and the number of the multiple permanent magnet assemblies are all 4, and each permanent magnet assembly is opposite to a first stator pole in the circumferential direction; or, each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

[0012] Furthermore, the number of the multiple first stator poles and the number of the multiple second stator poles are both 4, the number of the multiple permanent magnet assemblies is 8, each permanent magnet assembly is opposite to a first stator pole in the circumferential direction, and each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

[0013] Furthermore, the number of the multiple first stator poles and the number of the multiple second stator poles are both 8, the number of the multiple permanent magnet assemblies is 4, each permanent magnet assembly is opposite to a first stator pole in the circumferential direction, or each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

[0014] Furthermore, each first stator magnetic pole is arranged corresponding to a second stator magnetic pole and at least partially overlaps in the axial direction.

[0015] Furthermore, the stator also includes a second suspension control component, which is configured to apply a radial suspension force to the rotor. The second suspension control component includes a plurality of third stator poles, which are evenly arranged in the circumferential direction. The plurality of permanent magnet components are clamped between the first suspension control component and the second suspension control component, and generate equal or nearly equal magnetic flux at the third air gap of each pair of radially symmetrical two third stator poles or the third air gap of each third stator pole.

[0016] Furthermore, the number of the multiple third stator poles and the number of the multiple permanent magnet assemblies are both 4, and each permanent magnet assembly is opposite to a third stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between two adjacent third stator poles.

[0017] Furthermore, a first electromagnetic winding is provided on the first stator magnetic pole, a second electromagnetic winding is provided on the second stator magnetic pole, and a third electromagnetic winding is provided on the third stator magnetic pole.

[0018] Furthermore, a plurality of motor slots are formed on the side of each third stator pole facing the rotor, motor teeth are formed between two adjacent motor slots, and a motor slot gap is formed between two adjacent third stator poles, and the motor slot gap is configured as a motor slot.

[0019] Furthermore, the rotor includes a rotor body, a first ring edge and a second ring edge extending from the rotor body toward the stator, the first air gap is formed between the first stator pole and the first ring edge, and the second air gap is formed between the second stator pole and the first ring edge; the second ring edge is hollowed out at equal intervals to form a plurality of rotor poles, and the third air gap is formed between the rotor pole and the third stator pole.

[0020] Furthermore, the number of the rotor poles is an even number greater than or equal to 2, or the number of the rotor poles is the same as the number of the third stator poles and is not an even number.

[0021] Furthermore, the number of the rotor magnetic poles is 8, and the number of the third stator magnetic poles is 4.

[0022] Furthermore, the first control component also includes an annular first magnetic conductive substrate, the multiple first stator magnetic poles are formed on the first magnetic conductive substrate and protrude toward the rotor; the second control component also includes an annular second magnetic conductive substrate, the multiple second stator magnetic poles are formed on the second magnetic conductive substrate and protrude toward the rotor, and the second suspension control component also includes an annular third magnetic conductive substrate, the multiple third stator magnetic poles are formed on the third magnetic conductive substrate and protrude toward the rotor, and the third magnetic conductive substrate, the permanent magnet component, the first magnetic conductive substrate and the second magnetic conductive substrate are stacked together in sequence along the axial direction.

[0023] Furthermore, the permanent magnet assembly includes at least one axially magnetized permanent magnet.

[0024] Furthermore, each permanent magnet assembly includes multiple permanent magnets, which are arranged in the same radial plane, and the distance between two adjacent permanent magnets is the same or nearly the same. The multiple permanent magnets are arranged in a straight line in the radial plane, and the line between the center of the permanent magnet assembly and the projection point of the rotation axis of the rotor in the radial plane is perpendicular or nearly perpendicular to the straight line.

[0025] Furthermore, each permanent magnet assembly includes multiple permanent magnets, which are arranged in the same radial plane, and the distance between two adjacent permanent magnets is the same or nearly the same. The multiple permanent magnets are arranged in a circular arc in the radial plane, and the projection point of the rotation axis of the rotor in the radial plane is the same or nearly the same distance from each of the permanent magnets.

[0026] Furthermore, in the circumferential direction, the distance between the outermost permanent magnets of two adjacent permanent magnet assemblies is the same as or nearly the same as the distance between two adjacent permanent magnets of the permanent magnet assembly.

[0027] Furthermore, the permanent magnet assembly includes a bearing block, on which a fixing groove corresponding to each permanent magnet is formed, and the permanent magnet is positioned in the corresponding fixing groove.

[0028] Furthermore, the stator also includes multiple first pressure plates and multiple second pressure plates, the first pressure plates are arranged on the outside of the third magnetic conductive substrate, the second pressure plates are arranged on the outside of the second magnetic conductive substrate, and the first pressure plates and the second pressure plates are locked together by fasteners.

[0029] The embodiment of the present disclosure further provides a magnetic levitation turntable, comprising a carrier and the magnetic levitation device, wherein the rotor positions the carrier via a plurality of support columns.

[0030] The beneficial effects of the present invention are as follows: In one case, the magnetic levitation device of the present invention can make the forces generated by the stator on the rotor at each air gap of the multiple first stator poles equal by evenly arranging multiple permanent magnet components in the circumferential direction and making the multiple permanent magnet components generate equal or nearly equal magnetic fluxes at the first air gap of each pair of radially symmetrical first stator poles of the first control component of the first levitation control component (axial levitation control) and the second air gap of each pair of radially symmetrical second stator poles of the second control component, thereby improving the radial fluctuation of the rotor when rotating at the equilibrium position. In another case, by evenly arranging multiple permanent magnet assemblies on the circumference and making the multiple permanent magnet assemblies generate equal or nearly equal magnetic flux at the first air gap of each first stator pole of the first control assembly of the first suspension control assembly (axial suspension control) and the second air gap of each second stator pole of the second control assembly, the force generated by the stator on the rotor at each air gap of the multiple first stator poles can be made equal. At the same time, the force generated by the stator on the rotor at each air gap of the multiple second stator poles can be made equal. That is, regardless of the first stator pole or the second stator pole, the net force on the x-axis and y-axis is zero, and the z-axis force component at each air gap is also equal. When the rotor rotates at the equilibrium position, the force applied by the permanent magnet bias magnetic field will be balanced, and the z-axis force component at different positions on the circumference will also be balanced. Therefore, while improving the radial fluctuation of the rotor when rotating at the equilibrium position, it can also improve the axial fluctuation of the rotor when rotating at the equilibrium position, thereby improving the rotation stability of the magnetic suspension turntable, ensuring the stable position of the load (wafer) on the turntable, and ensuring high reliability of the process. The magnetic levitation device of the present invention is designed for discrete permanent magnet components. Compared with integral annular permanent magnets, the manufacturing process is less difficult and the processing and manufacturing cost is lower. In addition, when assembling the magnetic levitation device, the permanent magnet bias magnetic field of the discrete permanent magnet components is weaker, which is convenient for assembly.

[0031] In order to make the above and other objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] FIG1 is a structural schematic diagram 1 (stereoscopic view) of an embodiment of a stator according to an embodiment of the present invention;

[0034] FIG2 is a second structural schematic diagram (stereoscopic view) of a stator according to an embodiment of the present invention;

[0035] FIG3 is a structural schematic diagram 1 (front view) of the first suspension control assembly in an embodiment of the present invention;

[0036] FIG4 is a second structural schematic diagram (stereoscopic view) of the first suspension control assembly in an embodiment of the present invention;

[0037] FIG5 is a second structural schematic diagram (stereoscopic view) of the second suspension control assembly in an embodiment of the present invention;

[0038] FIG6 is a third structural diagram (axial cross-sectional view) of a stator according to an embodiment of the present invention;

[0039] 7 is a fourth structural diagram (radial cross-sectional view) of a stator according to an embodiment of the present invention;

[0040] FIG8 is a schematic structural diagram (radial cross-sectional view) of another embodiment of the stator according to the present invention;

[0041] 9 is a schematic structural diagram (radial cross-sectional view) of another embodiment of the stator according to the present invention;

[0042] 10 is a schematic structural diagram (stereoscopic view) of an embodiment of a rotor according to an embodiment of the present invention;

[0043] FIG11 is a structural schematic diagram (stereoscopic view) of an embodiment of a magnetic levitation device according to an embodiment of the present invention;

[0044] FIG12 is a second structural schematic diagram (axial cross-sectional view) of an embodiment of a magnetic levitation device according to an embodiment of the present invention;

[0045] FIG13 is a schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles and the number of the permanent magnet assembly are both 4;

[0046] FIG14 is a second schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles and the number of the permanent magnet assembly are both 4;

[0047] FIG15 is a third schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles and the number of the permanent magnet assembly are both 4;

[0048] FIG16 is a fourth schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles and the number of the permanent magnet assembly are both 3;

[0049] FIG17 is a fourth schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles is 4 and the number of the permanent magnet assembly is 8;

[0050] FIG18 is a fifth schematic diagram of the relative position arrangement of the first and second stator magnetic poles and the permanent magnet assembly in an embodiment of the present invention, wherein the number of the first and second stator magnetic poles is 8 and the number of the permanent magnet assembly is 4;

[0051] FIG19 is a first schematic diagram illustrating the relative positional arrangement of the rotor, the third stator magnetic poles, and the permanent magnet assembly in an embodiment of the present invention, wherein the number of rotor magnetic poles is 8, and the number of third stator magnetic poles and the number of permanent magnet assemblies are both 4;

[0052] FIG20 is a schematic diagram showing the relative position arrangement of the third stator magnetic poles and the permanent magnet assemblies according to an embodiment of the present invention, wherein the number of the third stator magnetic poles is 8 and the number of the permanent magnet assemblies is 4;

[0053] FIG21 is a schematic diagram of the relative position arrangement of the third stator magnetic poles and the permanent magnet components in an embodiment of the present invention, wherein the number of the third stator magnetic poles is 4 and the number of the permanent magnet components is 8.

[0054] FIG22 is a schematic structural diagram (axial cross-sectional view) of an embodiment of a magnetic levitation turntable according to an embodiment of the present invention;

[0055] FIG23 is a structural schematic diagram (axial cross-sectional view) of yet another embodiment of the stator in the embodiment of the present invention. DETAILED DESCRIPTION

[0056] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0057] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention. The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a system, product or device comprising a series of units is not necessarily limited to those units explicitly listed, but may include other units that are not explicitly listed or are inherent to these products or devices.

[0058] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more, unless otherwise explicitly specified.

[0059] The drawings in this disclosure are not drawn strictly to scale, and the specific size and quantity of each structure can be determined according to actual needs. The drawings described in this disclosure are only schematic diagrams.

[0060] In the prior art, a magnetic levitation device includes a rotor and a stator. The stator includes a first suspension control assembly and a second suspension control assembly. The first suspension control assembly includes a first control assembly and a second control assembly. The stator magnetic poles are equally spaced in the circumferential direction. For example, the first control assembly includes three first stator magnetic poles equidistantly spaced around the circumference, with winding slots formed between the three first stator magnetic poles. Each first stator magnetic pole is provided with a first electromagnetic winding. The stator also includes a permanent magnet that provides a permanent magnetic bias magnetic field. The permanent magnet is annular and applies a permanent magnetic bias magnetic field to the rotor through the first and second layers of stator magnetic poles. However, for magnetic levitation devices with larger diameters, such as inner rotor magnetic levitation devices, the manufacturing process for large-diameter annular permanent magnet assemblies is very difficult and the processing and manufacturing costs are high. In addition, due to the strong permanent magnetic bias magnetic field provided by the permanent magnets, the monolithic structure is difficult to assemble. Therefore, it is necessary to consider using discrete permanent magnets, for example, placing permanent magnets at four equidistant locations (X+, X-, Y+, and Y-) on the circumference. This structure results in the permanent magnetic bias magnetic field (magnetic flux) generated by the multiple permanent magnets being unequal (unbalanced) at the air gaps of the multiple first stator poles of the first suspension control assembly, and also unequal (unbalanced) at the air gaps of the multiple second stator poles. This results in unequal forces exerted by the stator on the rotor at each air gap of the multiple first stator poles, resulting in non-zero combined forces on the x- and y-axes, and unequal z-axis forces at each air gap. Similarly, unequal forces exerted by the stator on the rotor at each air gap of the multiple second stator poles, resulting in non-zero combined forces on the x- and y-axes, and unequal z-axis forces at each air gap. Consequently, even when the rotor rotates in its equilibrium position, it will be subject to unbalanced forces exerted by the permanent magnetic bias magnetic field, causing radial and axial fluctuations in the rotor's operation, affecting the stability of the motor.

[0061] In order to solve the above problems, the present invention provides a magnetic levitation device. By designing the magnetic flux at the air gap of each pair of radially symmetrical stator poles in the same group or the air gap of multiple stator poles in the same group to be equal or nearly equal, the resultant force exerted by the permanent magnetic bias magnetic fields of multiple permanent magnetic components on the first circumference of the rotor can be zero, and the force exerted by the permanent magnetic bias magnetic field on the rotor when rotating in the equilibrium position is balanced, thereby improving the rotation stability of the magnetic levitation turntable, ensuring the stable position of the carrier (wafer) on the turntable, and ensuring the high reliability of the process.

[0062] In order to enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to Figures 1-21 and specific implementation methods.

[0063] FIG1 is a first structural schematic diagram (perspective view) of an embodiment of a stator according to an embodiment of the present invention; FIG2 is a second structural schematic diagram (perspective view) of an embodiment of a stator according to an embodiment of the present invention; FIG3 is a first structural schematic diagram (front view) of a first suspension control assembly according to an embodiment of the present invention; FIG4 is a second structural schematic diagram (perspective view) of the first suspension control assembly according to an embodiment of the present invention; FIG5 is a second structural schematic diagram (perspective view) of a second suspension control assembly according to an embodiment of the present invention; FIG6 is a fourth structural schematic diagram (axial cross-sectional view) of an embodiment of a stator according to an embodiment of the present invention; FIG7 is a fifth structural schematic diagram (radial cross-sectional view) of an embodiment of a stator according to an embodiment of the present invention; FIG8 is a structural schematic diagram (radial cross-sectional view) of another embodiment of a stator according to an embodiment of the present invention; FIG9 is a structural schematic diagram (radial cross-sectional view) of yet another embodiment of a stator according to an embodiment of the present invention; FIG10 is a first structural schematic diagram (perspective view) of an embodiment of a rotor according to an embodiment of the present invention; FIG11 is a first structural schematic diagram (perspective view) of an embodiment of a magnetic levitation device according to an embodiment of the present invention; and FIG12 is a second structural schematic diagram (axial cross-sectional view) of an embodiment of a magnetic levitation device according to an embodiment of the present invention.

[0064] According to an embodiment of the present disclosure, referring to Figures 1, 2, 3, 4 and 5, a magnetic levitation device includes a stator 1 and a rotor 2, the stator 1 includes a permanent magnet device 11 and a first levitation control component 12, the first levitation control component 12 includes a first control component 121 and a second control component 122 arranged in an axially staggered manner, the first control component 121 is configured to apply an axially upward levitation force to the rotor, and the second control component 122 is configured to apply an axially downward levitation force to the rotor. The first control component 121 includes a plurality of first stator poles 1211, which are evenly arranged in the circumferential direction; the second control component includes a plurality of second stator poles 1221, which are evenly arranged in the circumferential direction; the permanent magnet device 11 includes a plurality of permanent magnet components 111, which are evenly arranged in the circumferential direction and generate equal or nearly equal magnetic flux at the first air gap of each pair of radially symmetrical first stator poles 1211 or the first air gap of each first stator pole 1211, and generate equal or nearly equal magnetic flux at the second air gap of each pair of radially symmetrical second stator poles 1221 or the second air gap of each second stator pole 1221. Thus, in one case, by evenly arranging multiple permanent magnet assemblies in the circumferential direction and enabling the multiple permanent magnet assemblies to generate equal or nearly equal magnetic fluxes at the first air gap of each pair of radially symmetrical first stator poles of the first control assembly of the first suspension control assembly (axial suspension control) and at the second air gap of each pair of radially symmetrical second stator poles of the second control assembly, the forces generated by the stator on the rotor at each air gap of the multiple first stator poles can be made equal. At the same time, the forces generated by the stator on the rotor at each air gap of the multiple first stator poles can be made equal, that is, regardless of the first stator pole or the second stator pole, the resultant force on the x-axis and the y-axis is zero, and when the rotor rotates at the equilibrium position, a balanced force is exerted on it by the permanent magnet bias magnetic field, thereby improving the radial fluctuation of the rotor when rotating at the equilibrium position.In another case, by evenly arranging multiple permanent magnet assemblies on the circumference and making the multiple permanent magnet assemblies generate equal or nearly equal magnetic flux at the first air gap of each first stator pole of the first control assembly of the first suspension control assembly (axial suspension control) and the second air gap of each second stator pole of the second control assembly, the force generated by the stator on the rotor at each air gap of the multiple first stator poles can be made equal. At the same time, the force generated by the stator on the rotor at each air gap of the multiple second stator poles can be made equal. That is, regardless of the first stator pole or the second stator pole, the net force on the x-axis and y-axis is zero, and the z-axis force component at each air gap is also equal. When the rotor rotates at the equilibrium position, the force applied by the permanent magnet bias magnetic field will be balanced, and the z-axis force component at different positions on the circumference will also be balanced. While improving the radial fluctuation of the rotor when rotating at the equilibrium position, the axial fluctuation of the rotor when rotating at the equilibrium position can also be improved, thereby improving the rotation stability of the magnetic suspension turntable, ensuring the stable position of the carrier (wafer) on the turntable, and ensuring high reliability of the process.

[0065] In the above structure, the first suspension control assembly 12 is used to actively adjust the rotor's axial (z-axis) height. It primarily consists of a first control assembly 121 and a second control assembly 122, staggered along the axial direction. The first control assembly 121 is configured to apply an axially upward suspension force to the rotor, while the second control assembly 122 is configured to apply an axially downward suspension force to the rotor. By adjusting the upward and downward suspension forces applied to the rotor 2 by the first and second control assemblies, the rotor's axial height can be adjusted.

[0066] For example, referring to Figures 2, 3, and 4, the first control assembly 121 includes a plurality of first stator poles 1211, which are evenly arranged in the circumferential direction. A first electromagnetic winding 1212 is disposed on each of the first stator poles 1211. The second control assembly 122 includes a plurality of second stator poles 1221, which are evenly arranged in the circumferential direction. A second electromagnetic winding 1222 is disposed on each of the second stator poles 1221. In one embodiment, both the first and second electromagnetic windings are centralized windings, with a first current flowing through the first electromagnetic winding and a second current flowing through the second electromagnetic winding. For example, increasing the first current and / or decreasing the second current can cause the axially upward force applied by the first stator pole 1211 and the first electromagnetic winding 1212 to the rotor 2 to be greater than the axially downward force applied by the second stator pole 1221 and the second electromagnetic winding 1222 to the rotor 2, causing the rotor 2 to move axially upward along the stator 1, with the distance of movement depending on the magnitude of the increase in the first current and / or the magnitude of the decrease in the second current. The greater the magnitude of the increase in the first current and / or the magnitude of the decrease in the second current, the greater the distance of the upward movement. For example, decreasing the first current and / or increasing the second current can cause the axially upward force applied by the first stator pole 1211 and the first electromagnetic winding 1212 to be less than the axially downward force applied by the second stator pole 1221 and the second electromagnetic winding 1222 to the rotor 2, causing the rotor 2 to move axially downward along the stator 1, with the distance of movement depending on the magnitude of the decrease in the first current and / or the magnitude of the increase in the second current. The greater the magnitude of the decrease in the first current and / or the magnitude of the increase in the second current, the greater the distance of the downward movement. Therefore, in the magnetic levitation device according to the embodiment of the present disclosure, the position of the rotor 2 can be simply, flexibly and accurately adjusted in the axial direction of the stator 1 according to actual needs, thereby improving the controllability of the magnetic levitation device and making the magnetic levitation device have a broader application prospect.

[0067] In the above structure, the first stator pole 1211 and the second stator pole 1221 are uniformly arranged in the circumferential direction, which means that the distance between two adjacent stator poles is equal or nearly equal in the circumferential direction, but the distance between the two stator poles is not limited. For example, preferably, referring to Figures 3 and 4, the distance between two adjacent stator poles in the circumferential direction is designed to be as small as possible so that the length of the stator pole is extended as much as possible in the circumferential direction, so that when the permanent magnetic bias magnetic field generated by the permanent magnet and the electromagnetic field generated by the electromagnetic winding act on the corresponding air gap through the stator pole, a relatively uniform magnetic field can be obtained in the circumferential direction. Among them, the two adjacent stator poles can be the first stator pole and the second stator pole, or can be two adjacent first stator poles or two adjacent second stator poles. For example, in a preferred embodiment, referring to Figures 3 and 4, in the circumferential direction, a second stator pole 1221 is arranged between two adjacent first stator poles 1211, and a first stator pole 1211 is arranged between two adjacent second stator poles 1221, that is, multiple first stator poles and multiple second stator poles are arranged alternately, but not limited to this. In other embodiments, two or more second stator poles can be arranged between two adjacent first stator poles, or two or more first stator poles can be arranged between two adjacent second stator poles.

[0068] In the above structure, the multiple permanent magnet assemblies 111 are evenly arranged in the circumferential direction, which means that the multiple permanent magnet assemblies are equidistantly arranged at multiple positions in the circumferential direction. For example, referring to FIG2 , a commonly used configuration structure is: permanent magnet assemblies 111 are respectively arranged at four equidistant positions (X+, X-, Y+, Y-) on the circumference. There is a preset distance between two adjacent permanent magnet assemblies 111 in the circumferential direction, wherein a preset distance can be configured as the lead-out position of a cable. The cable here can be, for example, a lead-out cable of an electromagnetic winding, or a lead-out cable of a sensor in a magnetic levitation system.

[0069] In the above structure, each pair of radially symmetrical two first stator poles or each pair of radially symmetrical two second stator poles, and each pair of radially symmetrical two third stator poles mentioned below means that the two stator poles are equally spaced 180 degrees in the circumferential direction, that is, one stator pole coincides with the other stator pole after rotating 180 degrees.

[0070] In order to achieve equality or near equality of the magnetic flux generated by the multiple permanent magnet assemblies at the first air gap of each pair of radially symmetrical first stator poles 1211 of the first control assembly and at the second air gap of each pair of radially symmetrical second stator poles 1221 of the second control assembly, in one embodiment, the number of the multiple first stator poles, the number of the multiple second stator poles, and the number of the multiple permanent magnet assemblies are all designed to be an even number greater than or equal to 2. Since the multiple first stator poles and the multiple second stator poles are evenly arranged in the circumferential direction, and the multiple permanent magnet assemblies are also evenly arranged in the circumferential direction, as long as the number of the first and second stator poles and the permanent magnet assemblies are all designed to be an even number greater than or equal to 2, the same magnetic flux can be generated at the air gap of each pair of radially symmetrical stator poles. As a result, the magnetic flux generated by the multiple permanent magnet assemblies at the air gaps of the multiple pairs of radially symmetrical stator poles (first and second stator poles) can achieve a balanced effect in the radial plane. That is, the resultant force of the first and second stator magnetic poles on the x-axis and y-axis is zero, and the rotor is subjected to a balanced force by the permanent magnetic bias magnetic field when rotating in the equilibrium position. In another embodiment, the number of the plurality of first stator magnetic poles, the number of the plurality of second stator magnetic poles, and the number of the plurality of permanent magnetic assemblies can also be designed to be the same and not an even number. Among them, when the number of the first stator magnetic poles is the same as the number of the second stator magnetic poles, it is convenient to alternately arrange them in the circumferential direction, reduce the axial size of the product, and the permanent magnetic bias magnetic field provided by the plurality of permanent magnetic assemblies is equal at the air gap of each stator magnetic pole in the same group. When the number of the first stator magnetic poles, the number of the second stator magnetic poles, and the number of permanent magnetic assemblies are all the same, there is no need to limit the relative azimuth angle, and the magnetic flux generated by the plurality of permanent magnetic assemblies will be balanced on each stator magnetic pole, so the force applied to the rotor by the plurality of stator magnetic poles evenly distributed in the circumferential direction must be balanced. Referring to FIG. 16 , in one specific embodiment, the number of first stator magnetic poles, the number of second stator magnetic poles, and the number of permanent magnet assemblies are all designed to be three. The three first stator magnetic poles and the three second stator magnetic poles are arranged alternately, and each permanent magnet assembly is equidistantly positioned between an adjacent first stator magnetic pole and a second stator magnetic pole. However, this is not limiting. In other embodiments, the permanent magnet assembly may also be designed to oppose one of the first and second stator magnetic poles.

[0071] Since the permanent magnet assembly provides a permanent magnet bias magnetic field for the first suspension control assembly mentioned above, it also provides a permanent magnet bias magnetic field for the second suspension control assembly described below, and the permanent magnet assembly is usually arranged in four orientations of two perpendicular degrees of freedom, it is preferred that the number of the plurality of first stator poles and the number of the plurality of second stator poles are designed to be the same and both are even numbers. More preferably, the number of the plurality of first stator poles, the number of the plurality of second stator poles, and the number of the plurality of permanent magnet assemblies are all designed to be 4. Referring to Figure 13, in one embodiment, the four first stator poles 1211 and the four second stator poles 1221 are alternately arranged, and each permanent magnet assembly 111 is opposite to a first stator pole 1211 in the circumferential direction. Referring to Figure 14, in another embodiment, the four first stator poles 1211 and the four second stator poles 1221 are alternately arranged, and each permanent magnet component 111 is opposite to a second stator pole 1221 in the circumferential direction; referring to Figure 15, in yet another embodiment, in the circumferential direction, each permanent magnet component 111 is equidistantly arranged between an adjacent first stator pole 1211 and a second stator pole 1221.

[0072] In one embodiment, referring to FIG17 , the number of the plurality of first stator poles 1211 and the number of the plurality of second stator poles 1221 are both four, the number of the plurality of permanent magnet assemblies 111 is eight, each permanent magnet assembly 111 is circumferentially opposite to a first stator pole 1211, and each permanent magnet assembly 111 is circumferentially opposite to a second stator pole 1221. The number of first and second stator poles is the same, facilitating alternating arrangement in the circumferential direction. The number of stator poles is 1 / 2 of the number of permanent magnet assemblies, facilitating that each permanent magnet assembly corresponds to a first or second stator pole. Thus, the magnetic flux in the air gap of the same or different groups of stator poles is equal. In another embodiment, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole in the circumferential direction. In this embodiment, the number of permanent magnet assemblies is twice the number of stator poles, but is not limited thereto. In other embodiments, for example, the number of stator poles may be twice the number of permanent magnet assemblies, and a permanent magnet assembly may also correspond to a first or second stator pole. Referring to FIG. 18 , the number of the plurality of first stator poles 1211 and the number of the plurality of second stator poles 1221 are both 8, the number of the plurality of permanent magnet assemblies 111 is 4, and each permanent magnet assembly 111 is circumferentially opposite to a first stator pole 1211, or each permanent magnet assembly is circumferentially opposite to a second stator pole; or each permanent magnet assembly is equidistantly disposed between adjacent first and second stator poles in the circumferential direction.

[0073] According to an embodiment of the present disclosure, referring to Figures 1, 2, 5 and 6, the stator 1 further includes a second suspension control component 13, which is configured to apply a radial suspension force to the rotor. The second suspension control component 13 includes a plurality of third stator poles 131, which are evenly arranged in the circumferential direction. A plurality of permanent magnet components 111 are clamped between the first suspension control component 12 and the second suspension control component 13, and generate equal or nearly equal magnetic flux at the third air gap of each pair of radially symmetrical third stator poles 131 or at the third air gap of each third stator pole 131. In this way, in one case, the multiple permanent magnet assemblies 111 generate equal or nearly equal magnetic fluxes at the third air gaps of each pair of radially symmetrical third stator poles 131 of the second suspension control assembly 13 (radial suspension control), so that the forces generated by the stator 1 on the rotor 2 at each air gap of the multiple third stator poles 131 are equal, that is, the net force of the third stator poles 131 on the x-axis and y-axis is zero, and the rotor 2 is subjected to a balanced force from the permanent magnet bias magnetic field when rotating at the equilibrium position, thereby improving the radial fluctuation of the rotor when rotating at the equilibrium position. In another case, by making multiple permanent magnet components 111 generate equal or nearly equal magnetic flux at the third air gap of each third stator pole 131 of the second suspension control component 13 (radial suspension control), the force generated by the stator 1 on the rotor 2 at each air gap of the multiple third stator poles 131 can be equal, and the z-axis component force at each air gap is also equal. When the rotor rotates at the equilibrium position, it is subjected to a balanced force exerted by the permanent magnet bias magnetic field, and the z-axis component force at different positions in the circumferential direction is also balanced. In this way, while improving the radial fluctuation of the rotor when rotating at the equilibrium position, the axial fluctuation of the rotor when rotating at the equilibrium position can also be improved, thereby improving the stability of the rotation of the magnetic suspension turntable, ensuring the stability of the position of the carrier (wafer) on the turntable, and ensuring that the process has high reliability.

[0074] In this embodiment, referring to Figures 1 and 2 , the stator 1 is primarily composed of a first suspension control assembly 12 and a second suspension control assembly 13. The first suspension control assembly 12 is primarily used for active axial control of the rotor, while the second magnetic suspension control assembly 13 is primarily used for active radial control of the rotor 2. This allows for stable radial suspension of the rotor 2 while simultaneously controlling the axial suspension height of the rotor 2. The second suspension control assembly 13 includes a plurality of third stator magnetic poles 131, which are evenly arranged in the circumferential direction and are provided with third electromagnetic windings 132. In one embodiment, the third electromagnetic winding 132 is a concentrated winding. The plurality of third stator magnetic poles 131 and the third electromagnetic winding 132 include a +X winding coil and magnetic pole, a -X winding coil and magnetic pole, a +Y winding coil and magnetic pole, and a -Y winding coil and magnetic pole. Increasing the current in the +X winding coil and / or decreasing the current in the -X winding coil can cause the force exerted by the +X winding coil and magnetic pole on the rotor 2 in the -X direction to be greater than the force exerted by the -X winding coil and magnetic pole on the rotor 2 in the +X direction. This causes the rotor 2 to move in the -X direction of the stator 1, while conversely, the rotor 2 moves in the +X direction of the stator 1, thereby achieving active control of the rotor in the x degree of freedom. Based on the same principle, the rotor 2 can be moved in the -Y direction of the stator 1, while conversely, the rotor 2 moves in the +Y direction of the stator 1, thereby achieving active control of the rotor in the y degree of freedom. It should be noted that the +X winding coil and magnetic pole, -X winding coil and magnetic pole, +Y winding coil and magnetic pole, and -Y winding coil and magnetic pole here can be a single winding coil and a single magnetic pole, or can be the resultant force generated by multiple winding coils and multiple magnetic poles.

[0075] In one embodiment, referring to FIG19 , the number of the plurality of third stator poles 131 and the number of the plurality of permanent magnet assemblies 111 are both four, and each permanent magnet assembly 111 is circumferentially opposite to a third stator pole 131. Thus, the number of third stator poles 131 is the same as the number of orientations in which the permanent magnet assemblies 111 are arranged, both being four. This facilitates the arrangement of the third electromagnetic winding 132 on the two perpendicular degrees of freedom (x and y) of the rotor 2 by the four third stator poles 131. Since the permanent magnetic bias magnetic field provided by the four permanent magnet assemblies 111 is balanced on each third stator pole 131, the forces applied to the rotor 2 by the four third stator poles 131 evenly distributed in the circumferential direction are necessarily balanced. Preferably, the permanent magnet assemblies 111 are arranged in a four-equally distributed pattern, which can achieve a better match with the x and y degrees of freedom. In another embodiment, in the circumferential direction, each permanent magnet assembly 111 is equidistant (circumferentially) between two adjacent third stator poles 131. In other embodiments, the number of permanent magnet assemblies 111 may be n times the number of third stator poles 131, or the number of third stator poles 131 may be n times the number of permanent magnet assemblies 111, where n is a natural number greater than or equal to 2. Referring to FIG20 , the number of permanent magnet assemblies 111 is 4, the number of third stator poles 131 is 8, and the number of third stator poles 131 is twice the number of permanent magnet assemblies 111. Referring to FIG21 , the number of permanent magnet assemblies 111 is 8, the number of third stator poles 131 is 4, and the number of permanent magnet assemblies 1111 is twice the number of third stator poles 131.

[0076] In one embodiment, referring to FIG5 , each third stator pole 131 is formed with a plurality of motor slots 134 on the side facing the rotor 2. Motor teeth 135 are formed between two adjacent motor slots 134. A motor slot gap 133 is formed between two adjacent third stator poles 131. The motor slot gap 133 is configured as a single motor slot 134. In this manner, a rotating electromagnetic winding 16 for rotation control can be disposed within the motor slot 134 to achieve rotation control of the rotor 2. The third electromagnetic winding 132 is disposed on the side of the rotating electromagnetic winding 16 facing away from the rotor 2. The permanent magnetic bias magnetic field generated by the permanent magnet assembly 111 is sequentially guided through the third stator pole 131 (the iron core of the electromagnetic winding) to the motor teeth 135. A third air gap is formed between the motor teeth 135 and the rotor 2, thereby achieving an integrated design of motor rotation control and radial suspension control, optimizing the motor rotation control structure and suspension control structure, and achieving a compact structure. In one embodiment, the rotating electromagnetic winding 16 can be a concentrated winding, wherein the motor teeth are configured as the core of the concentrated winding, see Figure 5, and the concentrated winding is wound around the corresponding motor teeth. In another embodiment, the rotating electromagnetic winding 16 can also be designed as a distributed winding.

[0077] In one embodiment, referring to FIG10 , the rotor 2 includes a rotor body 21, a first rim 22 (i.e., a first layer) extending from the rotor body 21 toward the stator 1, and a second rim (i.e., a second layer). A first air gap is formed between the first stator pole 1211 and the first rim 22, and a second air gap is formed between the second stator pole 1221 and the first rim. The second rim is hollowed out at equal intervals to form a plurality of rotor poles 23, and a third air gap is formed between the rotor pole 23 and the third stator pole 131. For example, the rotor 2 is formed of a magnetic material, examples of which include, but are not limited to, permanent magnetic materials or ferromagnetic materials. Furthermore, for example, the ferromagnetic material is a soft magnetic material having a magnetic permeability much greater than that of a vacuum, examples of which include, but are not limited to, iron, cobalt, nickel, and their alloys, carbon steel, silicon steel, and electrical pure iron. Examples of permanent magnetic materials include, but are not limited to, samarium cobalt, neodymium iron boron, and ferrite. The upward axial force exerted on the rotor 2 by the first stator pole 1211 and the first electromagnetic winding 1212, and the downward axial force exerted on the rotor 2 by the second stator pole 1221 and the second electromagnetic winding 1222, simultaneously act on the first rim 22 of the rotor 2. Because the plurality of first stator poles 1211 and the plurality of second stator poles 1221 are evenly arranged around the circumference of the rotor 2, the interaction between the first stator poles 1211 and the first electromagnetic winding 1212, and the second stator poles 1221 and the second electromagnetic winding 1222, and the first rim 22 ensures that the rotor 2 is stably suspended in the axial direction, with a resultant force of zero in the radial direction.

[0078] In one embodiment, the number of rotor poles 23 is an even number greater than or equal to 2, and the number of rotor poles 23 is the same as the number of third stator poles 131. The rotor poles 23 are primarily used to cooperate with the rotating electromagnetic winding 16 to achieve rotor rotation control. Furthermore, due to the integrated design of the second suspension control assembly 13 for radial suspension control and the motor stator (motor teeth and rotating electromagnetic winding) for motor rotation control, the permanent magnetic bias magnetic field generated by the multiple permanent magnet assemblies 111 acts on the rotor poles 23 of the rotor 2 through the multiple third stator poles 131 of the second suspension control assembly 13. Setting the number of rotor poles 23 and the number of third stator poles 131 to an even number greater than or equal to 2 allows for the generation of the same magnetic flux at the air gap of each radially symmetrical pair of rotor poles. Consequently, the magnetic flux acting on the rotor pole air gap by the multiple permanent magnet assemblies through each pair of radially symmetrical third stator poles is balanced within the radial plane. In another embodiment, the number of rotor magnetic poles is the same as the number of third stator magnetic poles and is not an even number. For example, when the number of permanent magnet assemblies and the number of third stator magnetic poles are both 3, the number of rotor magnetic poles may also be 3. In this way, the magnetic flux of the multiple permanent magnet assemblies acting on the air gap of the rotor magnetic pole through each third stator magnetic pole can also be balanced in the radial plane.

[0079] Since the rotor poles 23 are primarily used to cooperate with the rotating electromagnetic winding 16 to achieve rotor rotation control, in a preferred embodiment, as shown in FIG19 , the number of rotor poles is eight, and the number of third stator poles is four. In this case, each third stator pole corresponds to the same number of rotor poles, and the force applied by the permanent magnetic bias field during rotor rotation remains balanced, thereby ensuring the stability of the magnetic levitation turntable's rotation, and thus the stable position of the load (wafer) on the turntable, ensuring high process reliability.

[0080] In one embodiment, referring to Figures 3, 4, and 5, the first control assembly 121 further includes an annular first magnetic conductive substrate 1210, with a plurality of first stator magnetic poles 1221 formed on the first magnetic conductive substrate 1210 and protruding toward the rotor 2. The second control assembly 122 further includes an annular second magnetic conductive substrate 1220, with a plurality of second stator magnetic poles 1221 formed on the second magnetic conductive substrate 1220 and protruding toward the rotor. The second suspension control assembly 13 further includes an annular third magnetic conductive substrate 130, with a plurality of third stator magnetic poles 131 formed on the third magnetic conductive substrate 130 and protruding toward the rotor 2. Continuing with Figure 6, the third magnetic conductive substrate 130, the permanent magnet assembly 111, the first magnetic conductive substrate 1210, and the second magnetic conductive substrate 1220 are sequentially stacked together along the axial direction. In this way, the magnetic fields generated by the multiple permanent magnet assemblies can be simultaneously guided to the multiple first stator poles via the first magnetic conductive substrate. The magnetic fields generated by the multiple permanent magnet assemblies can also be simultaneously guided to the multiple second stator poles via the second magnetic conductive substrate. Simultaneously, the magnetic fields generated by the multiple permanent magnet assemblies can also be simultaneously guided to the multiple third stator poles via the third magnetic conductive substrate. The first magnetic circuit of the permanent magnet assembly is as follows: the magnetic flux originates from one end of the permanent magnet assembly and passes through the first magnetic conductive substrate, the first stator pole, the first air gap, the first rim of the rotor, the rotor body, the rotor pole of the rotor, the third air gap, the third stator pole, the third magnetic conductive substrate, and returns to the other end of the permanent magnet assembly. Simultaneously, the second magnetic circuit of the permanent magnet assembly is as follows: the magnetic flux originates from one end of the permanent magnet assembly and passes through the first magnetic conductive substrate, the second magnetic conductive substrate, the second stator pole, the second air gap, the first rim of the rotor, the rotor body, the rotor pole of the rotor, the third air gap, the third stator pole, the third magnetic conductive substrate, and returns to the other end of the permanent magnet assembly. In this embodiment, for ease of explanation, the first magnetic conductive substrate and the second magnetic conductive substrate are described as two components to facilitate processing and manufacturing, but the present invention is not limited to this. In other embodiments, the first magnetic conductive substrate and the second magnetic conductive substrate can also be an integral structure. In this case, the first stator magnetic pole and the second stator magnetic pole are both formed on the magnetic conductive substrate of the integral structure. In the above embodiment, the first stator magnetic pole and the first magnetic conductive substrate are described as two components, but the present invention is not limited to this. In other embodiments, the first stator magnetic pole and the first magnetic conductive substrate can be formed as one piece. Similarly, the second stator magnetic pole and the second magnetic conductive substrate are described as two components, and the second stator magnetic pole and the second magnetic conductive substrate can also be formed as one piece. The first stator magnetic pole and the first magnetic conductive substrate, the second stator magnetic pole and the second magnetic conductive substrate, and the third stator magnetic pole and the third magnetic conductive substrate are all formed of magnetic conductive materials. Furthermore, for example, the magnetic conductive material is a ferromagnetic material; the ferromagnetic material is, for example, a soft magnetic material whose magnetic permeability is much greater than the magnetic permeability of vacuum, examples of which include but are not limited to iron, cobalt, nickel and its alloys, carbon steel, silicon steel, and electrical pure iron.

[0081] In each of the above embodiments, a permanent magnet assembly is used to provide a permanent magnet bias magnetic field. Multiple permanent magnet assemblies are equidistantly arranged around the periphery of the rotor. In one embodiment, each permanent magnet assembly includes at least one axially magnetized permanent magnet 1111. That is, the permanent magnet assembly at each position around the rotor can be a single permanent magnet or two or more permanent magnets. Each axially magnetized permanent magnet can simultaneously provide magnetic flux for the first, second, and third stator poles. Examples of permanent magnets include, but are not limited to, samarium cobalt, neodymium iron boron, and ferrite.

[0082] In one embodiment, referring to FIG7 , each permanent magnet assembly 111 includes a plurality of permanent magnets 1111 . The plurality of permanent magnets 1111 are arranged in the same radial plane, the distance between two adjacent permanent magnets 1111 is the same or nearly the same, the plurality of permanent magnets 1111 are arranged in a straight line in the radial plane, and the line connecting the center of the permanent magnet assembly 111 and the projection of the rotor's rotation axis in the radial plane is perpendicular or nearly perpendicular to the straight line. For example, when the permanent magnet device 111 is configured as a four-position permanent magnet assembly 111 , the four permanent magnet assemblies 111 are respectively arranged at four equidistant positions around the rotor periphery, i.e., the four configuration positions of the permanent magnet device 111 are X+, X−, Y+, and Y−. When each permanent magnet assembly 111 includes a plurality of permanent magnets 1111 , the plurality of permanent magnets 1111 of each permanent magnet assembly 111 are arranged in a straight line at the four configuration positions, and the directions extending from the arrangement straight line of the four permanent magnet assemblies 111 are the x-degree of freedom direction and the y-degree of freedom direction.

[0083] In one embodiment, referring to FIG8 , each permanent magnet assembly 111 includes a plurality of permanent magnets 1111 . The plurality of permanent magnets are arranged in the same radial plane, with the distance between adjacent permanent magnets being the same or nearly the same. The plurality of permanent magnets are arranged in an arc in the radial plane, and the projection of the rotor's rotation axis in the radial plane is the same or nearly the same distance from each permanent magnet. That is, the plurality of permanent magnets 1111 in each configuration orientation of the permanent magnet assembly 111 are the same or nearly the same distance from the rotation axis. Thus, the plurality of permanent magnets 1111 are arranged in an arc shape overall. Due to the adaptation to the annular rotor, the stator poles (the first stator pole, the second stator pole and the third stator pole) are usually designed to be an arc centered on the rotor's rotation axis, and the multiple permanent magnets 1111 are also designed to be an arc at the same distance from the rotor's rotation axis. This can make the magnetic circuit of each permanent magnet 1111 at each configuration orientation more consistent, so that the magnetic flux at the air gap between the stator pole and the rotor is more evenly distributed on the partial circumference corresponding to the configuration orientation, thereby further improving the axial fluctuation during rotor rotation, and thereby improving the stability of the rotation of the magnetic levitation turntable.

[0084] In one embodiment, referring to FIG9 , the multiple permanent magnets 1111 of the permanent magnet assembly 111 at each configuration orientation are designed to be at the same or nearly the same distance from the rotation axis. In the circumferential direction, the distance between the outermost permanent magnets 1111 of two adjacent permanent magnet assemblies 111 is the same or nearly the same as the distance between two adjacent permanent magnets 1111 of the permanent magnet assembly 111. That is, the distance between any two permanent magnets is the same or nearly the same throughout the circumferential direction. This allows the magnetic circuit of each permanent magnet 1111 throughout the circumference to be more consistent, thereby making the magnetic flux at the air gap between the stator poles and the rotor more evenly distributed throughout the circumference, thereby further improving the axial fluctuation during rotor rotation and, in turn, improving the rotation stability of the magnetic levitation turntable.

[0085] In one embodiment, referring to Figures 7, 8 and 9, the permanent magnet assembly includes a bearing block 1112 and at least one permanent magnet 1111, and a fixing groove 1113 corresponding to each permanent magnet 1111 is formed on the bearing block 1112, and the permanent magnet 1111 is positioned in the corresponding fixing groove 1113. By arranging the fixing groove on the bearing block, the function of fixing the permanent magnet can be achieved, and the permanent magnet can be positioned in the fixing groove by a tight fit or other fixing methods. The shape of the fixing groove is adapted to the shape of the permanent magnet. For example, when the permanent magnet is in the shape of a square column, the fixing groove can be designed as a square groove, but is not limited thereto. The shape of the permanent magnet can also be designed as an arc (tile shape) or the like.

[0086] In the above-described embodiments, the third magnetic conductive substrate, permanent magnet assembly, first magnetic conductive substrate, and second magnetic conductive substrate of the stator are sequentially stacked together in the axial direction. The present invention does not limit the method of stacking and fixing them together, as long as they can be fixed together. In a preferred embodiment, referring to FIG1 , the stator 1 further includes a plurality of first pressure plates 14 and a plurality of second pressure plates 15 . The first pressure plates 14 are disposed on the outside of the third magnetic conductive substrate 130 , and the second pressure plates 15 are disposed on the outside of the second magnetic conductive substrate 1220 . The first pressure plates 14 and the second pressure plates 15 are locked together by fasteners.

[0087] It should be noted that, for ease of illustration, Figures 13 to 18 of the above embodiments illustrate only the relative positions of the permanent magnet assembly, the first stator pole, and the second stator pole as projected in a radial plane. Similarly, Figures 19 to 21 of the above embodiments illustrate only the relative positions of the permanent magnet assembly, the third stator pole, and the rotor as projected in a radial plane. In a specific product, referring to Figure 6 , the permanent magnet assembly and the first stator pole, the permanent magnet assembly and the second stator pole, the first stator pole and the second stator pole, and the permanent magnet assembly and the third stator pole are not located in the same radial plane, but are axially offset.

[0088] Based on the same inventive concept, the disclosed embodiments further provide a magnetic levitation turntable, comprising a carrier 3 and the aforementioned magnetic levitation device, wherein the rotor 2 supports and positions the carrier 3 via a plurality of support columns 4. Thus, the carrier 3 and the rotor 2 are connected via a plurality of support columns, and the stator 1 is configured to drive the rotor 2 and the carrier 3 to rotate and levitate. Thus, the magnetic levitation turntable can be used as semiconductor processing equipment in semiconductor manufacturing, for example, in rapid thermal processing and other wafer processing in semiconductor manufacturing, such as chemical vapor deposition, heat treatment, ion implantation, and other doping techniques. The carrier can be used to support wafers.

[0089] It should be noted that, for the sake of convenience, the above embodiments and all drawings show the situation where the stator 1 is arranged around the rotor 2; however, unless otherwise specified, the description of the embodiments of the present disclosure is also applicable to the situation where the rotor 2 surrounds the stator 1.

[0090] It should be noted that, for ease of illustration, the above-described embodiments and all accompanying drawings illustrate an embodiment in which a plurality of first stator poles and a plurality of second stator poles are alternately arranged. In another embodiment, each first stator pole is arranged corresponding to a second stator pole and at least partially overlaps in the axial direction. Referring to FIG23 , the first stator pole 1211 and the corresponding second stator pole 1221 completely overlap in the axial direction. Corresponding to this structure, the rotor 2 includes a rotor body 21, a first rim A22 extending from the rotor body 21 toward the stator 1, a first rim B22′, and a second rim. A first air gap is formed between the first stator pole 1211 and the first rim A22, and a second air gap is formed between the second stator pole 1221 and the first rim B22′. The second rim is hollowed out at equal intervals to form a plurality of rotor poles 23, and a third air gap is formed between the rotor pole 23 and the third stator pole 131. Corresponding to this structure, the first control component 121 also includes an annular first magnetic conductive substrate 1210, and multiple first stator magnetic poles 1221 are formed on the first magnetic conductive substrate 1210 and protrude toward the rotor 2; the second control component 122 also includes an annular second magnetic conductive substrate 1220, and multiple second stator magnetic poles 1221 are formed on the second magnetic conductive substrate 1220 and protrude toward the rotor, and a magnetic conductive material 1230 is connected between the first magnetic conductive substrate 1210 and the second magnetic conductive substrate 1220, so that the magnetic flux of the permanent magnet component 111 is guided through the first magnetic conductive substrate 1210, the magnetic conductive material 1230 and the second magnetic conductive substrate 1220 to the second air gap between the second stator magnetic pole 1221 and the first ring edge B22' of the rotor 2, and then returns to the permanent magnet component 111 through the rotor body 21, the rotor magnetic pole 23, the third air gap, the third stator magnetic pole 131, and the third magnetic conductive substrate 130, thereby forming a magnetic circuit. In addition, the magnetic flux of the permanent magnet assembly 111 returns to the permanent magnet assembly 111 through the first magnetic conductive substrate 1210, the first stator pole 1211, the first ring edge A22 of the rotor 2, the second air gap, the rotor body 21, the rotor pole 23, the third air gap, the third stator pole 131, and the third magnetic conductive substrate 130 to form a magnetic circuit.

[0091] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A magnetic suspension device, comprising a stator (1) and a rotor (2), wherein the stator comprises a permanent magnet device (11) and a first suspension control component (12), wherein the first suspension control component comprises a first control component (121) and a second control component (122) which are staggered in an axial direction, wherein the first control component is configured to apply an axially upward suspension force to the rotor, and the second control component is configured to apply an axially downward suspension force to the rotor, wherein: The first control component comprises a plurality of first stator magnetic poles (1211), which are evenly arranged in the circumferential direction; the second control component comprises a plurality of second stator magnetic poles (1221), which are evenly arranged in the circumferential direction; the permanent magnet device comprises a plurality of permanent magnet components (111), which are evenly arranged in the circumferential direction and generate equal or nearly equal magnetic fluxes at the first air gap of each pair of radially symmetrical two first stator magnetic poles or the first air gap of each first stator magnetic pole, and generate equal or nearly equal magnetic fluxes at the second air gap of each pair of radially symmetrical two second stator magnetic poles or the second air gap of each second stator magnetic pole.

2. The magnetic suspension device according to claim 1, characterized in that: The number of the multiple first stator poles, the number of the multiple second stator poles and the number of the multiple permanent magnet components are all even numbers greater than or equal to 2, or the number of the multiple first stator poles, the number of the multiple second stator poles and the number of the multiple permanent magnet components are the same and not an even number.

3. The magnetic suspension device according to claim 2, characterized in that: The number of the plurality of first stator poles is the same as the number of the plurality of second stator poles and is an even number.

4. The magnetic suspension device according to claim 3, characterized in that: In the circumferential direction, a second stator magnetic pole is arranged between two adjacent first stator magnetic poles, and a first stator magnetic pole is arranged between two adjacent second stator magnetic poles.

5. The magnetic suspension device according to claim 4, characterized in that: The number of the multiple first stator poles, the number of the multiple second stator poles and the number of the multiple permanent magnet assemblies are all 4, and each permanent magnet assembly is opposite to a first stator pole in the circumferential direction; or, each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

6. The magnetic suspension device according to claim 4, characterized in that: The number of the multiple first stator poles and the number of the multiple second stator poles are both 4, the number of the multiple permanent magnet assemblies is 8, each permanent magnet assembly is opposite to a first stator pole in the circumferential direction, and each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

7. The magnetic suspension device according to claim 4, characterized in that: The number of the multiple first stator poles and the number of the multiple second stator poles are both 8, the number of the multiple permanent magnet assemblies is 4, each permanent magnet assembly is opposite to a first stator pole in the circumferential direction, or each permanent magnet assembly is opposite to a second stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between an adjacent first stator pole and a second stator pole.

8. The magnetic suspension device according to claim 3, characterized in that: Each first stator magnetic pole is arranged corresponding to a second stator magnetic pole and at least partially overlaps in the axial direction.

9. The magnetic suspension device according to any one of claims 1 to 8, characterized in that: The stator also includes a second suspension control component (13), which is configured to apply a radial suspension force to the rotor. The second suspension control component includes a plurality of third stator poles (131), which are evenly arranged in the circumferential direction. The plurality of permanent magnet components are clamped between the first suspension control component and the second suspension control component, and generate equal or nearly equal magnetic flux at the third air gap of each pair of radially symmetrical two third stator poles or at the third air gap of each third stator pole.

10. The magnetic suspension device according to claim 9, characterized in that: The number of the plurality of third stator poles and the number of the plurality of permanent magnet assemblies are both 4, and each permanent magnet assembly is opposite to a third stator pole in the circumferential direction; or, in the circumferential direction, each permanent magnet assembly is equidistantly arranged between two adjacent third stator poles.

11. The magnetic suspension device according to claim 10, characterized in that: The first stator magnetic pole is provided with a first electromagnetic winding (1212), the second stator magnetic pole is provided with a second electromagnetic winding (1222), and the third stator magnetic pole is provided with a third electromagnetic winding (132).

12. The magnetic suspension device according to claim 11, characterized in that: A plurality of motor slots (134) are formed on one side of each third stator magnetic pole facing the rotor, motor teeth (135) are formed between two adjacent motor slots, and a motor slot gap (133) is formed between two adjacent third stator magnetic poles, wherein the motor slot gap is configured as one motor slot.

13. The magnetic suspension device according to claim 9, characterized in that: The rotor comprises a rotor body (21), a first ring edge (22) and a second ring edge extending from the rotor body toward the stator, the first air gap is formed between the first stator magnetic pole and the first ring edge, and the second air gap is formed between the second stator magnetic pole and the first ring edge; the second ring edge is hollowed out at equal intervals to form a plurality of rotor magnetic poles (23), and the third air gap is formed between the rotor magnetic pole and the third stator magnetic pole.

14. The magnetic suspension device according to claim 13, characterized in that: The number of the rotor poles is an even number greater than or equal to 2, or the number of the rotor poles is the same as the number of the third stator poles and is not an even number.

15. The magnetic suspension device according to claim 14, characterized in that: The number of the rotor magnetic poles is 8, and the number of the third stator magnetic poles is 4.

16. The magnetic suspension device according to claim 9, characterized in that: The first control component also includes an annular first magnetic conductive substrate (1210), and the plurality of first stator magnetic poles are formed on the first magnetic conductive substrate and protrude toward the rotor; the second control component also includes an annular second magnetic conductive substrate (1220), and the plurality of second stator magnetic poles are formed on the second magnetic conductive substrate and protrude toward the rotor; the second suspension control component also includes an annular third magnetic conductive substrate (130), and the plurality of third stator magnetic poles are formed on the third magnetic conductive substrate and protrude toward the rotor; the third magnetic conductive substrate, the permanent magnet component, the first magnetic conductive substrate and the second magnetic conductive substrate are sequentially stacked together along the axial direction.

17. The magnetic suspension device according to claim 16, characterized in that: The permanent magnet assembly comprises at least one axially magnetized permanent magnet (1111).

18. The magnetic levitation device according to claim 16, characterized in that: Each permanent magnet assembly comprises a plurality of permanent magnets (1111), wherein the plurality of permanent magnets are arranged in the same radial plane, the distance between two adjacent permanent magnets is the same or nearly the same, the plurality of permanent magnets are arranged in a straight line in the radial plane, and the line connecting the center of the permanent magnet assembly and the projection point of the rotation axis of the rotor in the radial plane is perpendicular or nearly perpendicular to the straight line.

19. The magnetic levitation device according to claim 16, characterized in that: Each permanent magnet assembly includes a plurality of permanent magnets, and the plurality of permanent magnets are arranged in the same radial plane, and the distance between two adjacent permanent magnets is the same or nearly the same. The plurality of permanent magnets are arranged in a circular arc in the radial plane, and the projection point of the rotation axis of the rotor in the radial plane is the same or nearly the same distance from each of the permanent magnets.

20. The magnetic suspension device according to claim 19, characterized in that: In the circumferential direction, the distance between the outermost permanent magnets of two adjacent permanent magnet assemblies is the same as or nearly the same as the distance between two adjacent permanent magnets of the permanent magnet assembly.

21. The magnetic suspension device according to claim 17, characterized in that: The permanent magnet assembly comprises a bearing block (1112), on which a fixing groove (1113) corresponding to each permanent magnet is formed, and the permanent magnet is positioned in the corresponding fixing groove.

22. The magnetic suspension device according to claim 16, characterized in that: The stator further comprises a plurality of first pressing plates (14) and a plurality of second pressing plates (15), wherein the first pressing plates are arranged on the outer side of the third magnetic conductive substrate, and the second pressing plates are arranged on the outer side of the second magnetic conductive substrate, and the first pressing plates and the second pressing plates are locked together by fasteners.

23. A magnetic levitation turntable, characterized in that: It comprises a carrier (3) and the magnetic suspension device according to any one of claims 1 to 22, wherein the rotor supports and positions the carrier via a plurality of support columns (4).

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