TWI902384B - Magnetic suspension device and magnetic suspension turntable - Google Patents

Abstract

The present disclosure provides a magnetic suspension device and a magnetic suspension turntable. The magnetic suspension device comprises a stator and a rotator. The stator comprises a permanent magnetic device and a first suspension control component. The first suspension control component comprises a first control component and a second control component. The first control component is configured to apply an upward axial suspension force to the rotator. The second control component is configured to apply a downward axial suspension force to the rotator. The first component comprises a plurality of first stator magnetic poles. The second component comprises a plurality of second stator magnetic poles. The permanent magnetic device comprises a plurality of permanent magnetic components. The plurality of permanent magnetic components is uniformly disposed in a circumferential direction. And a magnetic flux of each pair of the first stator magnetic poles in a radial symmetry at a first air gap or of each first stator magnetic pole at the first air gap, is equal or nearly equal. And a magnetic flux of each pair of the second stator magnetic poles in a radial symmetry at a second air gap or each second stator magnetic pole at the second air gap, is equal or nearly equal. The present disclosure can improve a stability of the rotation of the magnetic suspension turntable.

Description

Magnetic levitation device and magnetic levitation turntable

This invention relates to the field of magnetic levitation technology, specifically a magnetic levitation device and a magnetic levitation turntable.

A magnetic levitation device is a rotary drive that uses magnetic field force to levitate the rotor, eliminating any mechanical contact between the rotor and stator. Magnetic levitation devices or rotary drives are characterized by high cleanliness, no precipitation, no particles, no dynamic seals, and superior performance, making them promising for applications in ultra-clean drive fields such as biochemistry, medicine, and semiconductor manufacturing.

In semiconductor manufacturing, wafer cleanliness is crucial because it affects the yield of subsequent semiconductor processes and products. To achieve ultra-cleanliness, silicon or other semiconductor wafers must be processed in a controlled, ultra-clean atmosphere. For example, one step in wafer fabrication is annealing the wafer after ion implantation doping. Doping applies strain to the crystal structure; if this stress is not released quickly, it will cause undesirable changes in the resistivity of the ion-doped material. Currently, rapid thermal processing (RT) is commonly used for annealing. On the other hand, wafer processing uniformity is crucial. To achieve uniformity, the wafer is typically rotated around its center vertical axis or z-axis during processing. Rotation is also used in other wafer processing steps, such as chemical vapor deposition, heat treatment, ion implantation doping, and other doping techniques. To meet the stringent requirements of ultra-cleanliness and processing uniformity in semiconductor manufacturing, semiconductor heat treatment equipment ideally employs a non-contact, rotary-driven magnetic levitation turntable. In addition to the stator and rotor of the magnetic levitation device, the magnetic levitation turntable also includes a support structure for the wafer. The stator generates a magnetic field to drive the rotor and support structure to rotate and levitate. Based on the difference in the relative positions of the stator and rotor, magnetic levitation turntables can be divided into those with an inner rotor and those with an outer rotor.

For example, a magnetic levitation device includes a rotor and a stator. The stator includes a first levitation control component (corresponding to the first layer of the rotor) and a second levitation control component (corresponding to the second layer of the rotor). The first levitation control component includes a first control component and a second control component. Their stator poles are equally spaced in the circumferential direction. For example, the first control component includes three first stator poles equidistantly arranged in a circle, with winding slots formed between the three first stator poles. Each first stator pole has a first electromagnetic winding. The stator also includes a permanent magnet that provides a permanent magnet bias field. The permanent magnet is a toroidal body. The permanent magnet bias field is applied to the rotor through the first and second layers of stator poles. However, for magnetic levitation devices with a larger diameter... For example, the manufacturing process of large-diameter toroidal permanent magnets for internal rotor-type magnetic levitation devices is very difficult and the manufacturing cost is high. Furthermore, due to the strong permanent magnet bias field provided by the permanent magnets, the overall structure presents assembly difficulties. Therefore, it is necessary to consider using discrete permanent magnets, for example, setting permanent magnets at four equidistant locations (X+, X-, Y+, Y-) on the circumference. In this structure, on the one hand, the permanent magnet bias magnetic fields (magnetic flux) generated by multiple permanent magnets are not equal (uneven) at the air gaps of the multiple first stator poles of the first suspension control component, and are also not equal (uneven) at the air gaps of the multiple second stator poles. This results in unequal forces generated by the stator on the rotor at each air gap of the multiple first stator poles, with the resultant force on the x-axis and y-axis not being zero, and the component force on the z-axis not being equal at each air gap. Similarly, the forces generated by the stator on the rotor at each air gap of the multiple second stator poles are not equal, with the resultant force on the x-axis and y-axis not being zero, and the component force on the z-axis not being equal at each air gap. In this way, the rotor will also be subjected to unbalanced forces exerted by the permanent magnet bias field when rotating in the equilibrium position, which will lead to radial and axial fluctuations in rotor operation and affect the stability of motor operation.

In order to overcome the deficiencies in the prior art, 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.

This disclosure embodiment discloses a magnetic levitation device, including a stator and a rotor. The stator includes a permanent magnet device and a first levitation control component. The first levitation control component includes a first control component and a second control component arranged in staggered layers along the axial direction. The first control component is configured to apply an upward axial levitation force to the rotor, and the second control component is configured to apply a downward axial levitation force to the rotor. The device is characterized in that the first control component includes a plurality of first stator magnetic poles, which are uniformly arranged in the circumferential direction. The second control component includes multiple second stator magnetic poles, which are uniformly arranged in the circumferential direction; the permanent magnet device includes multiple 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 first stator magnetic poles or at the first air gap of each first stator magnetic pole, and generate equal or nearly equal magnetic flux at the second air gap of each pair of radially symmetrical second stator magnetic poles or at the second air gap of each second stator magnetic pole.

Furthermore, the number of the plurality of first stator magnetic poles, the plurality of second stator magnetic poles, and the plurality of permanent magnet components are all even numbers greater than or equal to 2; or, the number of the plurality of first stator magnetic poles, the plurality of second stator magnetic poles, and the plurality of permanent magnet components are all the same and not even numbers.

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

Furthermore, in the circumferential direction, a second stator pole is disposed between two adjacent first stator poles, and a first stator pole is disposed between two adjacent second stator poles.

Furthermore, the number of the plurality of first stator magnetic poles, the plurality of second stator magnetic poles, and the plurality of permanent magnet components are all four, with each permanent magnet component positioned opposite a first stator magnetic pole in the circumferential direction; or, each permanent magnet component positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between an adjacent first stator magnetic pole and a second stator magnetic pole.

Furthermore, the number of the plurality of first stator magnetic poles and the number of the plurality of second stator magnetic poles are both four, and the number of the plurality of permanent magnet components is eight. Each permanent magnet component is positioned opposite a first stator magnetic pole in the circumferential direction, and each permanent magnet component is positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly arranged between an adjacent first stator magnetic pole and a second stator magnetic pole.

Furthermore, the number of the plurality of first stator magnetic poles and the number of the plurality of second stator magnetic poles are both eight, and the number of the plurality of permanent magnet components is four. Each permanent magnet component is positioned opposite a first stator magnetic pole in the circumferential direction, or each permanent magnet component is positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between an adjacent first stator magnetic pole and a second stator magnetic pole.

Furthermore, each first stator pole is configured to correspond to a second stator pole and at least partially overlap in the axial direction.

Furthermore, the stator also includes a second suspension control component configured to apply a radial suspension force to the rotor. The second suspension control component includes a plurality of third stator magnetic poles uniformly arranged in the circumferential direction. The plurality of permanent magnet components are sandwiched 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 third stator magnetic poles or at the third air gap of each third stator magnetic pole.

Furthermore, the number of the plurality of third stator magnetic poles and the number of the plurality of permanent magnet components are both four, with each permanent magnet component positioned opposite a third stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly arranged between two adjacent third stator magnetic poles.

Furthermore, the first stator pole is provided with a first electromagnetic winding, the second stator pole is provided with a second electromagnetic winding, and the third stator pole is provided with a third electromagnetic winding.

Furthermore, each third stator magnetic pole has multiple motor slots on the side facing the rotor, motor teeth are formed between two adjacent motor slots, and motor slot gaps are formed between two adjacent third stator magnetic poles, wherein the motor slot gaps are configured as one motor slot.

Furthermore, the rotor includes a rotor body, a first ring edge and a second ring edge extending from the rotor body to the stator, a first air gap is formed between the first stator magnetic pole and the first ring edge, and a second air gap is formed between the second stator magnetic pole and the first ring edge; the second ring edge is equally spaced to form multiple rotor magnetic poles, and a third air gap is formed between the rotor magnetic poles and the third stator magnetic pole.

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

Furthermore, the number of rotor poles is 8, and the number of third stator poles is 4.

Furthermore, the first control component further includes a ring-shaped first magnetic substrate, on which the plurality of first stator magnetic poles are formed and protrude toward the rotor; the second control component further includes a ring-shaped second magnetic substrate, on which the plurality of second stator magnetic poles are formed and protrude toward the rotor; the second levitation control component further includes a ring-shaped third magnetic substrate, on which the plurality of third stator magnetic poles are formed and protrude toward the rotor; the third magnetic substrate, the permanent magnet component, the first magnetic substrate, and the second magnetic substrate are sequentially stacked together along the axial direction.

Furthermore, the permanent magnet component includes at least one axially magnetized permanent magnet.

Furthermore, each permanent magnet component includes multiple permanent magnets arranged in the same radial plane, with the distance between any two adjacent permanent magnets being the same or nearly the same. The multiple permanent magnets are arranged in a straight line in the radial plane, and the line connecting the center of the permanent magnet component and the projection point of the rotation axis of the rotor in the radial plane is perpendicular or nearly perpendicular to the straight line.

Furthermore, each permanent magnet component includes multiple permanent magnets arranged in the same radial plane, with the distance between any two adjacent permanent magnets being the same or nearly the same. The multiple permanent magnets are arranged in an arc in the radial plane, and the projection point of the rotor's axis of rotation in the radial plane is the same or nearly the same as the distance between each of the permanent magnets.

Furthermore, in the circumferential direction, the distance between the outermost permanent magnets of two adjacent permanent magnet components is the same as or nearly the same as the distance between two adjacent permanent magnets of the permanent magnet component.

Furthermore, the permanent magnet component includes a support block, on which a fixing groove corresponding to each permanent magnet is formed, and the permanent magnet is positioned in the corresponding fixing groove.

Furthermore, the stator also includes multiple first pressure plates and multiple second pressure plates, the first pressure plates being disposed on the outer side of the third magnetic substrate, the second pressure plates being disposed on the outer side of the second magnetic substrate, and the first pressure plates and the second pressure plates being fastened together by fasteners.

This disclosure embodiment also provides a magnetic levitation turntable, including a carrier and the magnetic levitation device, wherein the rotor is positioned by a plurality of support columns supporting the carrier.

The beneficial effects of this invention are as follows: In one case, the magnetic levitation device of this invention, by uniformly arranging multiple permanent magnet components in the circumferential direction and making the multiple permanent magnet components produce equal or nearly equal air gaps at the first air gaps of the two radially symmetrical first stator magnetic poles of the first control component of the first levitation control component (axial levitation control) and at the second air gaps of the two radially symmetrical second stator magnetic poles of the second control component. The magnetic flux makes the force generated by the stator on the rotor at each air gap of the multiple first stator poles equal. At the same time, it makes the force generated by the stator on the rotor at each air gap of the multiple first stator poles equal. That is, regardless of whether it is the first stator pole or the second stator pole, the resultant force on the x-axis and y-axis is zero. When the rotor rotates in the equilibrium position, it is subjected to a balanced force by the permanent magnet bias magnetic field, thereby improving the radial fluctuation of the rotor when rotating in the equilibrium position. In another scenario, by uniformly arranging multiple permanent magnet components on a circumference and ensuring that these components generate equal or nearly equal magnetic flux at the first air gap of each first stator pole in the first control component of the first suspension control assembly (axial suspension control) and at the second air gap of each second stator pole in the second control assembly, the force exerted by the stator on the rotor at each air gap of the multiple first stator poles can be made equal. Simultaneously, the force exerted by the stator on the rotor at each air gap of the multiple second stator poles can also be made equal, meaning that regardless of whether it is the first stator pole or the second stator pole... The second stator magnetic pole has zero net force on the x and y axes, and the z-axis component force is equal at each air gap. When the rotor rotates in the equilibrium position, the force exerted by the permanent magnet bias field will be balanced, and the z-axis component force at different positions on the circumference will also be balanced. This not only improves the radial ripples of the rotor when rotating in the equilibrium position, but also improves the axial ripples of the rotor when rotating in the equilibrium position, thereby improving the stability of the magnetic levitation turntable rotation, ensuring the stability of the position of the carrier (wafer) on the turntable, and ensuring high reliability of the process. The magnetic levitation device of this invention is designed for discrete permanent magnet components. Compared with integral ring permanent magnets, the manufacturing process is less difficult and the processing 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 facilitates assembly.

The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a 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 a person skilled in the art without making any creative work are within the scope of protection of the present invention.

In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "comprising" and "featured," and any variations thereof, in the specification, claims, and the aforementioned accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a system, product, or device that includes a series of units is not necessarily limited to those units that are explicitly listed, but may include other units that are not explicitly listed or that are inherent to such products or devices.

Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "multiple" means two or more, unless otherwise expressly defined.

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

In the prior art, a magnetic levitation device includes a rotor and a stator. The stator includes a first levitation control component and a second levitation control component. The first levitation control component includes a first control component and a second control component. Their stator poles are equally spaced in the circumferential direction. For example, the first control component includes three first stator poles equidistantly arranged in a circle, with winding slots formed between the three first stator poles. Each first stator pole is provided with a first electromagnetic winding. The stator also includes a permanent magnet that provides a permanent magnet bias field. The permanent magnet is a toroidal body. The permanent magnet bias field is applied to the rotor through the first and second layers of stator poles. However, for magnetic levitation devices with a large diameter... For example, the manufacturing process of large-diameter toroidal permanent magnet components for internal rotor-type magnetic levitation devices is very difficult and the manufacturing cost is relatively high. In addition, due to the strong permanent magnet bias magnetic field provided by the permanent magnet, the overall structure is difficult to assemble. Therefore, it is necessary to consider using discrete permanent magnets, for example, setting permanent magnets at four equidistant locations (X+, X-, Y+, Y-) on the circumference. In this structure, on the one hand, the permanent magnet bias magnetic fields (magnetic flux) generated by multiple permanent magnets are not equal (uneven) at the air gaps of the multiple first stator poles of the first suspension control component, and are also not equal (uneven) at the air gaps of the multiple second stator poles. This results in unequal forces generated by the stator on the rotor at each air gap of the multiple first stator poles, with the resultant force on the x-axis and y-axis not being zero, and the component force on the z-axis not being equal at each air gap. Similarly, the forces generated by the stator on the rotor at each air gap of the multiple second stator poles are not equal, with the resultant force on the x-axis and y-axis not being zero, and the component force on the z-axis not being equal at each air gap. In this way, the rotor will also be subjected to unbalanced forces exerted by the permanent magnet bias field when rotating in the equilibrium position, which will lead to radial and axial fluctuations in rotor operation and affect the stability of motor operation.

To address the aforementioned issues, this invention provides a magnetic levitation device. By designing the magnetic flux at the air gaps of two radially symmetrical stator poles in the same group, or at the air gaps of multiple stator poles in the same group, to be equal or nearly equal, the resultant force exerted by the permanent magnet bias magnetic fields of multiple permanent magnet components on the first circumference of the rotor is zero. This ensures that the force exerted by the permanent magnet bias magnetic fields on the rotor is balanced when it rotates in the equilibrium position, thereby improving the stability of the magnetic levitation turntable rotation, ensuring the stability of the position of the carrier (wafer) on the turntable, and ensuring high reliability of the process.

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 embodiments.

Figure 1 is a three-dimensional structural diagram of an embodiment of the stator in this invention; Figure 2 is a three-dimensional structural diagram of an embodiment of the stator in this invention; Figure 3 is a three-dimensional structural diagram of a first suspension control component in this invention; Figure 4 is a three-dimensional structural diagram of a first suspension control component in this invention; Figure 5 is a three-dimensional structural diagram of a second suspension control component in this invention; Figure 6 is an axial sectional view of an embodiment of the stator in this invention; Figure 7 is... Figure 5 is a schematic diagram of the structure of one embodiment of the stator in the present invention (radial section); Figure 8 is a schematic diagram of the structure of another embodiment of the stator in the present invention (radial section); Figure 9 is a schematic diagram of the structure of yet another embodiment of the stator in the present invention (radial section); Figure 10 is a schematic diagram of the structure of one embodiment of the rotor in the present invention (stereoscopic view); Figure 11 is a schematic diagram of the structure of one embodiment of the magnetic levitation device in the present invention (stereoscopic view); Figure 12 is a schematic diagram of the structure of one embodiment of the magnetic levitation device in the present invention (axial section).

According to this disclosure embodiment, 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 axial staggered layers. The first control component 121 is configured to apply an axially upward levitation force to the rotor 2, and the second control component 122 is configured to apply an axially downward levitation force to the rotor 2. The first control component 121 includes multiple first stator magnetic poles 1211, which are uniformly arranged in the circumferential direction. The second control component 122 includes multiple second stator magnetic poles 1221, which are uniformly arranged in the circumferential direction. The permanent magnet device 11 includes multiple permanent magnet components 111, which are uniformly arranged in the circumferential direction. Equal or nearly equal magnetic flux is generated at the first air gap of each pair of radially symmetrical first stator magnetic poles 1211 or at the first air gap of each first stator magnetic pole 1211. Equal or nearly equal magnetic flux is also generated at the second air gap of each pair of radially symmetrical second stator magnetic poles 1221 or at the second air gap of each second stator magnetic pole 1221. In this way, in one scenario, by uniformly arranging multiple permanent magnet components 111 in the circumferential direction and ensuring that the multiple permanent magnet components 111 generate equal or nearly equal magnetic flux at the first air gap of each pair of radially symmetrical first stator magnetic poles 1211 of the first control component 121 of the first suspension control component 12 (axial suspension control) and at the second air gap of each pair of radially symmetrical second stator magnetic poles 1221 of the second control component 122, multiple permanent magnet components 111 can generate equal or nearly equal magnetic flux. The forces generated by the stator on the rotor 2 at each air gap of the first stator magnetic pole 1211 are equal. At the same time, the forces generated by the stator on the rotor 2 at each air gap of multiple first stator magnetic poles 1211 are equal. That is, regardless of whether it is the first stator magnetic pole 1211 or the second stator magnetic pole 1221, the resultant force on the x-axis and y-axis is zero. When the rotor 2 rotates in the equilibrium position, it is subjected to a balanced force by the permanent magnet bias magnetic field, thereby improving the radial fluctuation of the rotor 2 when rotating in the equilibrium position. In another scenario, by uniformly arranging multiple permanent magnet components 111 on a circumference and ensuring that equal or nearly equal magnetic flux is generated at the first air gap of each first stator pole 1211 of the first control component 121 of the first suspension control component 12 (axial suspension control) and at the second air gap of each second stator pole 1221 of the second control component 122, the force exerted by the stator on the rotor at each air gap of the multiple first stator poles 1211 can be made equal. Simultaneously, the force exerted by the stator on the rotor 2 at each air gap of the multiple second stator poles 1221 can also be made equal. That is, regardless of whether it is the first stator magnetic pole 1211 or the second stator magnetic pole 1221, the resultant force on the x-axis and y-axis is zero, and the component force on the z-axis at each air gap is also equal. When the rotor 2 rotates in the equilibrium position, the force applied by the permanent magnet bias field will be balanced, and the component force on the z-axis at different positions on the circumference will also be balanced. This improves the radial ripple of the rotor 2 when it rotates in the equilibrium position, and also improves the axial ripple of the rotor 2 when it rotates in the equilibrium position, thereby improving the stability of the rotation of the magnetic levitation turntable, ensuring the stability of the position of the carrier (wafer) on the turntable, and ensuring that the process has high reliability.

In the above structure, the first suspension control component 12 is used to actively adjust the rotor's axial (z-axis) height. It mainly consists of a first control component 121 and a second control component 122 arranged in staggered layers along the axial direction. The first control component 121 is configured to apply an upward axial suspension force to the rotor 2, and the second control component 122 is configured to apply a downward axial suspension force to the rotor 2. By adjusting the upward and downward suspension forces applied to the rotor 2 by the first control component 121 and the second control component 122, the function of adjusting the axial height of the rotor 2 can be realized.

For example, referring to Figures 2, 3, and 4, the first control component 121 includes multiple first stator poles 1211, which are uniformly arranged in the circumferential direction, and each first stator pole 1211 is provided with a first electromagnetic winding 1212. The second control component 122 includes multiple second stator poles 1221, which are uniformly arranged in the circumferential direction, and each second stator pole 1221 is provided with a second electromagnetic winding 1222. In one embodiment, both the first electromagnetic winding 1212 and the second electromagnetic winding 1222 are concentrated windings, with a first current flowing through the first electromagnetic winding 1212 and a second current flowing through the second electromagnetic winding 1222. For example, increasing the first current and/or decreasing the second current can make the upward axial force exerted by the first stator pole 1211 and the first electromagnetic winding 1212 on the rotor 2 greater than the downward axial force exerted by the second stator pole 1221 and the second electromagnetic winding 1222 on the rotor 2. The rotor 2 moves upward along the axis of the stator 1, and the distance moved depends 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 greater the magnitude of the decrease in the second current, the greater the distance moved upward. For example, by reducing the first current and/or increasing the second current, the upward force exerted by the first stator pole 1211 and the first electromagnetic winding 1212 on the rotor 2 along the axial direction can be less than the downward force exerted by the second stator pole 1221 and the second electromagnetic winding 1222 on the rotor 2 along the axial direction. The rotor 2 moves downward along the axial direction of the stator 1, and the distance moved depends on the magnitude of the reduction of the first current and/or the magnitude of the increase of the second current. The greater the magnitude of the reduction of the first current and/or the greater the magnitude of the increase of the second current, the greater the downward distance moved. Therefore, in the magnetic levitation device according to the present disclosure embodiment, the position of the rotor 2 can be easily, 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 wider range of application prospects.

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

In the above structure, the uniform arrangement of multiple permanent magnet components 111 in the circumferential direction means that the multiple permanent magnet components 111 are equidistantly arranged at multiple locations in the circumferential direction. For example, referring to Figure 2, a commonly used configuration is to arrange permanent magnet components 111 at four equidistant locations (X+, X-, Y+, Y-) on the circumference. Adjacent permanent magnet components 111 are spaced a predetermined distance apart in the circumferential direction, where one predetermined distance can be configured as the lead-out position of a cable. This cable can be, for example, the lead-out cable of an electromagnetic winding or the lead-out cable of a sensor in a magnetic levitation system.

In the above structure, each pair of radially symmetrical first stator magnetic poles 1211 or each pair of radially symmetrical second stator magnetic poles 1221, and each pair of radially symmetrical third stator magnetic poles 131 mentioned below, means that the two stator magnetic poles are equidistant from each other by 180 degrees in the circumferential direction, that is, one stator magnetic pole coincides with the other stator magnetic pole after rotating 180 degrees.

In order to ensure that the magnetic flux generated by the multiple permanent magnet components is equal or nearly equal at the first air gap of each pair of radially symmetrical first stator magnetic poles 1211 in the first control component 121 and at the second air gap of each pair of radially symmetrical second stator magnetic poles 1221 in the second control component 122, in one embodiment, the number of multiple first stator magnetic poles 1211, the number of multiple second stator magnetic poles 1221, and the number of multiple permanent magnet components 111 are all designed to be an even number greater than or equal to 2. Since multiple first stator poles 1211 and multiple second stator poles 1221 are uniformly arranged in the circumferential direction, and multiple permanent magnet components 111 are uniformly arranged in the circumferential direction, as long as the number of first stator poles 1211, second stator poles 1221 and permanent magnet components 111 is designed to be an even number greater than or equal to 2, the same magnetic flux can be generated at each pair of radially symmetrical stator pole air gaps. Thus, the magnetic flux generated by multiple permanent magnet components 111 at the air gaps of multiple pairs of radially symmetrical stator poles (first stator poles 1211 and second stator poles 1221) can achieve a balanced effect in the radial plane. This achieves zero resultant force on the x-axis and y-axis for the first stator pole 1211 and the second stator pole 1221, ensuring that the rotor 2 receives a balanced force from the permanent magnet bias field when rotating in the equilibrium position. In another embodiment, the number of multiple first stator poles 1211, multiple second stator poles 1221, and multiple permanent magnet components 111 can all be designed to be the same and not even. When the number of first stator poles 1211 and the number of second stator poles 1221 are the same, it facilitates alternating arrangement in the circumferential direction, reducing the axial dimension of the product, and the permanent magnet bias field provided by the multiple permanent magnet components 111 is equal at the air gap of each stator pole in the same group. When the number of first stator magnetic poles 1211, the number of second stator magnetic poles 1221, and the number of permanent magnet components 111 are all the same, there is no need to limit the relative orientation angle. The magnetic flux generated by the multiple permanent magnet components 111 will be balanced on each stator magnetic pole. Therefore, the force applied to the rotor 2 by the multiple stator magnetic poles evenly distributed in the circumferential direction will necessarily be balanced. Referring to Figure 16, in one specific embodiment, the number of first stator poles 1211, the number of second stator poles 1221, and the number of permanent magnet components 111 are all designed to be three. The three first stator poles 1211 and the three second stator poles 1221 are arranged alternately, and each permanent magnet component 111 is equidistantly arranged between an adjacent first stator pole 1211 and a second stator pole 1221. However, this is not a limitation. In other embodiments, the permanent magnet component 111 may also be designed to be opposite to one of the first stator poles 1211 and the second stator poles 1221.

Since the permanent magnet assembly 111 provides a permanent magnet bias field for both the first suspension control assembly 12 and the second suspension control assembly 13, and is typically positioned in four directions across two vertical degrees of freedom, it is preferable that the number of the plurality of first stator poles 1211 and the plurality of second stator poles 1221 be the same and both even. More preferably, the number of the plurality of first stator poles 1211, the plurality of second stator poles 1221, and the plurality of permanent magnet assemblies 111 are all designed to be four. Referring to Figure 13, in one embodiment, four first stator poles 1211 and four second stator poles 1221 are alternately arranged, with each permanent magnet component 111 facing one of the first stator poles 1211 in the circumferential direction. Referring to Figure 14, in another embodiment, four first stator poles 1211 and four second stator poles 1221 are alternately arranged, with each permanent magnet component 111 facing one of the second stator poles 1221 in the circumferential direction. Referring to Figure 15, in yet another embodiment, each permanent magnet component 111 is equidistantly arranged between adjacent first stator poles 1211 and second stator poles 1221 in the circumferential direction.

In one embodiment, referring to Figure 17, there are four first stator poles 1211 and four second stator poles 1221, and eight permanent magnet components 111. Each permanent magnet component 111 is positioned opposite one first stator pole 1211 in the circumferential direction, and each permanent magnet component 111 is positioned opposite one second stator pole 1221 in the circumferential direction. The positions are opposite; the number of first stator poles 1211 and second stator poles 1221 is the same, which facilitates their alternating arrangement in the circumferential direction. The number of stator poles is half the number of permanent magnet components, so that each permanent magnet component 111 corresponds to one first stator pole 1211 or one second stator pole 1221. In this way, the magnetic flux at the air gap of stator poles in the same or different groups is equal. In 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. In this embodiment, the number of permanent magnet components 111 is twice the number of stator poles, but it is not limited to this. In other embodiments, for example, the number of stator poles can also be twice the number of permanent magnet components 111, and the permanent magnet components 111 can also correspond to a first stator pole 1211 or a second stator pole 1221. Referring to Figure 18, there are 8 first stator poles 1211 and 8 second stator poles 1221, and 4 permanent magnet components 111. Each permanent magnet component 111 is opposite to a first stator pole 1211 in the circumferential direction, or each permanent magnet component 111 is opposite to a second stator pole 1221 in the circumferential direction; or, 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.

According to this disclosed embodiment, 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 2. The second suspension control component 13 includes a plurality of third stator magnetic poles 131, which are uniformly arranged in the circumferential direction. A plurality of permanent magnet components 111 are sandwiched 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 magnetic poles 131 or at the third air gap of each third stator magnetic pole 131. In this way, in one scenario, multiple permanent magnet components 111 generate equal or nearly equal magnetic flux at the third air gap of each pair of radially symmetrical third stator magnetic poles 131 in the second suspension control component 13 (radial suspension control). This makes the force generated by the stator 1 on the rotor 2 at each air gap of the multiple third stator magnetic poles 131 equal, that is, the resultant force of the third stator magnetic poles 131 on the x-axis and y-axis is zero. When the rotor 2 rotates in the equilibrium position, it is subjected to a balanced force by the permanent magnet bias magnetic field, thereby improving the radial fluctuation of the rotor 2 when rotating in the equilibrium position. In another scenario, by causing the multiple permanent magnet components 111 to generate equal or nearly equal magnetic flux at the third air gap of each third stator pole 131 in the second suspension control component 13 (radial suspension control), the force exerted by the stator 1 on the rotor 2 at each air gap of the multiple third stator poles 131 can be made equal, and the z-axis component force at each air gap is also equal. When the rotor 2 rotates in the equilibrium position, it is subjected to permanent magnets. The bias magnetic field applies a balanced force, and the z-axis component of the force is also balanced at different positions in the circumferential direction. In this way, the radial ripple of rotor 2 when rotating in the equilibrium position is improved, as well as the axial ripple of rotor 2 when rotating in the equilibrium position, which in turn improves the stability of the rotation of the magnetic levitation turntable, ensures the stability of the position of the carrier (wafer) on the turntable, and ensures high reliability of the process.

In this embodiment, referring to Figures 1 and 2, the stator 1 mainly consists of a first suspension control component 12 and a second suspension control component 13. The first suspension control component 12 is mainly used for active control of the rotor 2 in the axial direction, and the second suspension control component 13 is mainly used for active control of the rotor 2 in the radial direction, thereby controlling the axial suspension height of the rotor 2 while simultaneously controlling the stable radial suspension of the rotor 2. The second suspension control component 13 includes multiple third stator magnetic poles 131, which are uniformly arranged in the circumferential direction, and each third stator magnetic pole 131 is provided with a third electromagnetic winding 132. In one embodiment, the third electromagnetic winding 132 is a concentrated winding. The multiple 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 of the +X winding coil and/or decreasing the current of the -X winding coil can make the force exerted by the +X winding coil and magnetic pole on the rotor 2 in the -X direction greater than the force exerted by the -X winding coil and magnetic pole on the rotor 2 in the +X direction. The rotor 2 moves in the -X direction of the stator 1, and vice versa, the rotor 2 moves in the +X direction of the stator 1, thereby realizing active control of the rotor in the x-degree of freedom. Based on the same principle, rotor 2 can move along the -Y direction of stator 1, and conversely, rotor 2 can move along the +Y direction of 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 it can be the resultant force generated by multiple winding coils and multiple magnetic poles.

In one embodiment, referring to Figure 19, the number of multiple third stator poles 131 and the number of multiple permanent magnet components 111 are both four, with each permanent magnet component 111 positioned opposite a third stator pole 131 in the circumferential direction. Thus, the number of third stator poles 131 and the number of permanent magnet components 111 in their orientations are the same, both being four. This facilitates the placement of the third electromagnetic winding 132 on the two perpendicular degrees of freedom (x-degree of freedom and y-degree of freedom) of the rotor 2 by the four third stator poles 131. Since the permanent magnet bias magnetic field provided by the four permanent magnet components 111 is balanced on each third stator pole 131, the force applied to the rotor 2 by the four circumferentially distributed third stator poles 131 is necessarily balanced. Preferably, the permanent magnet components 111 are arranged in a four-part evenly distributed pattern, which can achieve better matching with the x and y degrees of freedom. In another embodiment, each permanent magnet component 111 is equidistant (circumferentially) between two adjacent third stator poles 131 in the circumferential direction. In other embodiments, the number of permanent magnet components 111 can be n times the number of third stator poles 131, or the number of third stator poles 131 can be n times the number of permanent magnet components 111, where n is a natural number greater than or equal to 2. Referring to Figure 20, the number of permanent magnet components 111 is 4, and the number of third stator poles 131 is 8, which is twice the number of permanent magnet components 111. Referring to Figure 21, there are 8 permanent magnet components 111 and 4 third stator poles 131. The number of permanent magnet components 111 is twice the number of third stator poles 131.

In one embodiment, referring to FIG5, each third stator pole 131 has multiple motor slots 134 formed on the side facing the rotor 2, motor teeth 135 are formed between two adjacent motor slots 134, and motor slot gaps 133 are formed between two adjacent third stator poles 131, with the motor slot gaps 133 configured as one motor slot 134. In this way, a rotating electromagnetic winding 16 for rotation control can be installed in the motor slot 134, which can realize the rotation control of the rotor 2. The third electromagnetic winding 132 is located on the side of the rotating electromagnetic winding 16 facing away from the rotor 2. The permanent magnet bias magnetic field generated by the permanent magnet component 111 is guided to the motor teeth 135 through the third stator magnetic pole 131 (the iron core of the electromagnetic winding) in sequence. A third air gap is formed between the motor teeth 135 and the rotor 2, realizing the integrated design of motor rotation control and radial suspension control, optimizing the motor rotation control structure and suspension control structure, and achieving the purpose of compact structure. In one embodiment, the rotary electromagnetic winding 16 can be a concentrated winding, wherein the motor teeth are configured as the core of the concentrated winding, as shown in Figure 5, with the concentrated winding wound around the corresponding motor teeth. In another embodiment, the rotary electromagnetic winding 16 can also be designed as a distributed winding.

In one embodiment, referring to FIG10, the rotor 2 includes a rotor body 21, a first annular rim 22 (i.e., a first layer) extending from the rotor body 21 toward the stator 1, and a second annular rim (i.e., a second layer). A first air gap is formed between the first stator pole 1211 and the first annular rim 22, and a second air gap is formed between the second stator pole 1221 and the first annular rim 22. Multiple rotor poles 23 are formed by equally spaced cutouts in the second annular rim, and a third air gap is formed between the rotor poles 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 magnet materials or ferromagnetic materials. Furthermore, the ferromagnetic material may be a soft magnetic material with a permeability much greater than that of 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 magnet materials include, but are not limited to, chromium-cobalt, neodymium iron boron, and ferrite. The axially upward force exerted on the rotor 2 by the first stator pole 1211 and the first electromagnetic winding 1212, and the axially downward force exerted on the rotor 2 by the second stator pole 1221 and the second electromagnetic winding 1222, act simultaneously on the first ring 22 of the rotor 2. Since multiple first stator magnetic poles 1211 and multiple second stator magnetic poles 1221 are uniformly arranged around the circumference of rotor 2, the interaction between the first stator magnetic poles 1211 and the first electromagnetic winding 1212, the second stator magnetic poles 1221 and the second electromagnetic winding 1222 and the first annular flange 22 makes rotor 2 stably suspended in the axial direction and the resultant force in the radial direction is zero.

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 mainly used in conjunction with the rotating electromagnetic winding 16 to achieve rotational control of the rotor 2. Simultaneously, due to the integrated design of the second suspension control component 13 for radial suspension control and the motor stator (motor teeth 135 and rotating electromagnetic winding 16) for motor rotation control, the permanent magnet bias magnetic field generated by the multiple permanent magnet components 111 will act on the rotor poles 23 of the rotor 2 through the multiple third stator poles 131 of the second suspension control component 13, thus controlling the rotor's rotation. The number of rotor poles 23 and the number of third stator poles 131 are both set to an even number greater than or equal to 2. This allows the same magnetic flux to be generated at the air gap of each pair of radially symmetrical rotor poles 23. Thus, the magnetic flux exerted by multiple permanent magnet components 111 on the air gap of the rotor poles 23 through each pair of radially symmetrical third stator poles 131 can achieve a balanced effect in the radial plane. In another embodiment, the number of rotor poles 23 is the same as the number of third stator poles 131 and is not even. For example, when the number of permanent magnet components 111 and the number of third stator poles 131 are both 3, the number of rotor poles 23 can also be 3. In this way, the magnetic flux of multiple permanent magnet components 111 acting on the air gap of rotor pole 23 through each third stator pole 131 can also be balanced in the radial plane.

Since the rotor poles 23 are mainly used in conjunction with the rotating electromagnetic winding 16 to realize the rotation control of the rotor 2, in a preferred embodiment, referring to Figure 19, the number of rotor poles 23 is 8 and the number of third stator poles is 4. At this time, the number of rotor poles 23 corresponding to each third stator pole 131 is still the same, and the force provided by the permanent magnet bias field during the rotation of the rotor 2 is still balanced, thereby ensuring the stability of the rotation of the magnetic levitation turntable, and further ensuring the stability of the position of the carrier (wafer) on the turntable, and ensuring high reliability of the process.

In one embodiment, referring to Figures 3, 4 and 5, the first control component 121 further includes an annular first magnetic substrate 1210, with a plurality of first stator magnetic poles 1211 formed on the first magnetic substrate 1210 and protruding toward the rotor 2; the second control component 122 further includes an annular second magnetic substrate 1220, with a plurality of second stator magnetic poles 1221 formed on the second magnetic substrate 1220 and protruding toward the rotor 2; and the second levitation control component 13 further includes an annular third magnetic substrate 130, with a plurality of third stator magnetic poles 131 formed on the third magnetic substrate 130 and protruding toward the rotor 2. Referring again to Figure 6, the third magnetic substrate 130, permanent magnet components 111, first magnetic substrate 1210, and second magnetic substrate 1220 are sequentially stacked together along the axial direction. In this way, the magnetic fields generated by the multiple permanent magnet components 111 can be simultaneously guided to the multiple first stator poles 1211 through the first magnetic substrate 1210, and the magnetic fields generated by the multiple permanent magnet components 111 can also be simultaneously guided to the multiple second stator poles 1221 through the second magnetic substrate 1220; at the same time, the magnetic fields generated by the multiple permanent magnet components 111 can also be simultaneously guided to the multiple third stator poles 131 through the third magnetic substrate 130. The first magnetic circuit of the permanent magnet assembly 111 is as follows: the magnetic flux starts from one end of the permanent magnet assembly 111, passes through the first magnetic substrate 1210, the first stator pole 1211, the first air gap, the first ring 22 of the rotor 2, the rotor body 21, the rotor pole 23 of the rotor 2, the third air gap, the third stator pole 131, and the third magnetic substrate 130, and returns to the other end of the permanent magnet assembly 111. Meanwhile, the second magnetic circuit of the permanent magnet assembly 111 is as follows: the magnetic flux starts from one end of the permanent magnet assembly 111, passes sequentially through the first magnetic substrate 1210, the second magnetic substrate 1220, the second stator pole 1221, the second air gap, the first ring 22 of the rotor 2, the rotor body 21, the rotor pole 23 of the rotor 2, the third air gap, the third stator pole 131, and the third magnetic substrate 130, and returns to the other end of the permanent magnet assembly 111. In this embodiment, for ease of explanation, the first magnetic substrate 1210 and the second magnetic substrate 1220 are described as two components for ease of processing and manufacturing, but are not limited thereto. In other embodiments, the first magnetic substrate and the second magnetic substrate can also be an integral structure. In this case, both the first stator pole 1211 and the second stator pole 1221 are formed on the integral magnetic substrate. In the above embodiments, the first stator pole 1211 and the first magnetic substrate 1210 are described as two components, but this is not a limitation. In other embodiments, the first stator pole 1211 and the first magnetic substrate 1210 can be integrally formed. Similarly, the second stator pole 1221 and the second magnetic substrate 1220 are described as two components, and the second stator pole 1221 and the second magnetic substrate 1220 can also be integrally formed. The first stator magnetic pole 1211 and the first magnetic substrate 1210, the second stator magnetic pole 1221 and the second magnetic substrate 1220, and the third stator magnetic pole 131 and the third magnetic substrate 130 are all formed of a magnetically conductive material 1230. Further, for example, the magnetically conductive material 1230 is a ferromagnetic material; ferromagnetic materials are, for example, soft magnetic materials with a permeability much greater than the permeability of vacuum, examples of which include, but are not limited to, iron, cobalt, nickel and their alloys, carbon steel, silicon steel, and electrical pure iron.

In the above embodiments, the permanent magnet component 111 is used to provide a permanent magnet bias magnetic field. Multiple permanent magnet components 111 are equidistantly arranged around the outer periphery of the rotor 2. In one embodiment, each permanent magnet component 111 includes at least one axially magnetized permanent magnet 1111. That is, the permanent magnet component 111 at each position around the rotor 2 can be a single permanent magnet or two or more permanent magnets 1111. The axial magnetization of each permanent magnet 1111 can simultaneously provide magnetic flux to the first stator pole 1211, the second stator pole 1221, and the third stator pole 131. Examples of permanent magnets 1111 include, but are not limited to, neodymium cobalt, neodymium iron boron, and ferrite.

In one embodiment, referring to Figure 7, each permanent magnet component 111 includes multiple permanent magnets 1111 arranged in the same radial plane. The distance between any two adjacent permanent magnets 1111 is the same or nearly the same. The multiple permanent magnets 1111 are arranged in a straight line in the radial plane, and the line connecting the center of the permanent magnet component 111 and the projection point of the rotation axis of the rotor 2 in the radial plane is perpendicular or nearly perpendicular to the straight line. For example, when the permanent magnet device 11 is configured with permanent magnet components 111 in four directions, the four permanent magnet components 111 are respectively arranged in four equidistant directions around the rotor 2, that is, the four configuration directions of the permanent magnet device 11 are X+, X-, Y+, and Y-. When each permanent magnet component 111 includes multiple permanent magnets 1111, the multiple permanent magnets 1111 of each permanent magnet component 111 are arranged in a straight line at four configuration positions. Then the extension direction of the straight line of the arrangement of the four permanent magnet components 111 is the x-degree-of-freedom direction and the y-degree-of-freedom direction.

In one embodiment, referring to Figure 8, each permanent magnet component 111 includes multiple permanent magnets 1111. These permanent magnets 1111 are arranged in the same radial plane, with the distance between any two adjacent permanent magnets 1111 being the same or nearly the same. The multiple permanent magnets 1111 are arranged in an arc within the radial plane. The projection point of the rotation axis of the rotor 2 onto the radial plane is the same or nearly the same distance from each permanent magnet 1111. That is, the distances of the multiple permanent magnets 1111 from the rotation axis are the same or nearly the same at each configuration location, thus the overall arrangement of the multiple permanent magnets 1111 forms an arc. Because it is adapted to a toroidal rotor, the stator poles (first stator pole 1211, second stator pole 1221 and third stator pole 131) are usually designed as arcs centered on the rotation axis of the rotor 2. The multiple permanent magnets 1111 are also designed as arcs with the same distance from the rotation axis of the rotor 2. This makes the magnetic circuit of each permanent magnet 1111 in each configuration position more consistent, so that the magnetic flux at the air gap between the stator poles and the rotor 2 is more evenly distributed on the corresponding part of the circumference, thereby further improving the axial fluctuation when the rotor 2 rotates, and thus improving the stability of the magnetic levitation turntable rotation.

In one embodiment, referring to Figure 9, the 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 axis of rotation. 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 1111 is the same or nearly the same along the entire circumference. This makes the magnetic circuit of each permanent magnet 1111 on the entire circumference more consistent, thereby making the magnetic flux at the air gap between the stator pole and the rotor 2 more uniformly distributed on the entire circumference, further improving the axial fluctuation when the rotor 2 rotates, and thus improving the stability of the magnetic levitation turntable rotation.

In one embodiment, referring to Figures 7, 8, and 9, the permanent magnet component 111 includes a support block 1112 and at least one permanent magnet 1111. A fixing groove 1113 corresponding to each permanent magnet 1111 is formed on the support block 1112, and the permanent magnet 1111 is positioned within the corresponding fixing groove 1113. By providing the fixing groove 1113 on the support block 1112, the function of fixing the permanent magnet 1111 can be achieved. The permanent magnet 1111 can be positioned within the fixing groove 1113 by a tight fit or other fixing method. The shape of the fixing groove 1113 is adapted to the shape of the permanent magnet 1111. For example, when the permanent magnet 1111 is square prism-shaped, the fixing groove 1113 can be designed as a square groove, but it is not limited to this. The shape of the permanent magnet 1111 can also be designed as arc-shaped (tile-shaped), etc.

In the above embodiments, the third magnetic substrate 130, permanent magnet component 111, first magnetic substrate 1210, and second magnetic substrate 1220 of stator 1 are sequentially stacked together along 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, stator 1 further includes multiple first pressure plates 14 and multiple second pressure plates 15. The first pressure plates 14 are disposed on the outer side of the third magnetic substrate 130, and the second pressure plates 15 are disposed on the outer side of the second magnetic substrate 1220. The first pressure plates 14 and the second pressure plates 15 are locked together by fasteners.

It should be noted that, for the sake of illustration, Figures 13 to 18 in the above embodiments only illustrate the relative positions of the permanent magnet assembly, the first stator pole, and the second stator pole projected in the radial plane. Similarly, in the accompanying figures 19 to 21 of the above embodiments, only the relative positions of the permanent magnet assembly 111, the third stator pole 131 and the rotor 2 projected in the radial plane are illustrated. In the specific product, referring to Figure 6, the permanent magnet assembly 111 and the first stator pole 1211, the permanent magnet assembly 111 and the second stator pole 1221, the first stator pole 1211 and the second stator pole 1221, and the permanent magnet assembly 111 and the third stator pole 131 are not in the same radial plane, but are offset in the axial direction.

Based on the same inventive concept, this embodiment also provides a magnetic levitation turntable, including a carrier 3 and the aforementioned magnetic levitation device, wherein a 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 the plurality of support columns 4, and the stator 1 is configured to drive the rotor 2 and the carrier 3 to rotate and levitate. In this way, 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 doping, and other technical doping. The carrier can be used to support wafers.

It should be noted that, for ease of illustration, the above embodiments and all accompanying drawings show the case where the stator 1 is arranged around the rotor 2; however, unless otherwise stated, the description of the present disclosure embodiments also applies to the case where the rotor 2 is arranged around the stator 1.

It should be noted that, for ease of illustration, the embodiments shown above, as well as in all the accompanying figures, depict an embodiment where multiple first stator poles and multiple second stator poles are alternately arranged. In another embodiment, each first stator pole is correspondingly arranged with one second stator pole and at least partially overlaps in the axial direction. Referring to Figure 23, 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 ring 22 extending from the rotor body 21 to the stator 1, a first ring 22' and a second ring. A first air gap is formed between the first stator pole 1211 and the first ring 22, and a second air gap is formed between the second stator pole 1221 and the first ring 22'. Multiple rotor poles 23 are formed by equally spaced cutouts in the second ring, and a third air gap is formed between the rotor poles 23 and the third stator pole 131. Corresponding to this structure, the first control component 121 further includes a ring-shaped first magnetic substrate 1210, with a plurality of first stator magnetic poles 1211 formed on the first magnetic substrate 1210 and protruding toward the rotor 2; the second control component 122 further includes a ring-shaped second magnetic substrate 1220, with a plurality of second stator magnetic poles 1221 formed on the second magnetic substrate 1220 and protruding toward the rotor 2, and the first magnetic substrate 1210 and the second magnetic substrate 1220 are connected. A magnetic material 1230 is connected between 220 so that the magnetic flux of the permanent magnet assembly 111 is guided through the first magnetic substrate 1210, the magnetic material 1230 and the second magnetic substrate 1220 to the second air gap between the second stator magnetic pole 1221 and the first ring 22' of the rotor 2, and then returns to the permanent magnet assembly 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 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 substrate 1210, the first stator pole 1211, the first ring 22 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 substrate 130, forming a magnetic circuit.

This invention uses specific embodiments to illustrate the principles and implementation methods of the invention. The description of the above embodiments is only used to help understand the technical solution and core idea of the invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the invention. Therefore, the content of this specification should not be construed as a limitation of the invention.

1: Stator 11: Permanent Magnet Device 111: Permanent Magnet Component 1111: Permanent Magnet 1112: Bearing Block 1113: Fixing Slot 12: First Suspension Control Component 121: First Control Component 1210: First Magnetic Conductive Substrate 1211: First Stator Magnetic Pole 1212: First Electromagnetic Winding 122: Second Control Component 1220: Second Magnetic Conductive Substrate 1221: First Second stator pole 1222: Second electromagnetic winding 1230: Magnetic material 13: Second suspension control component 130: Third magnetic substrate 131: Third stator pole 132: Third electromagnetic winding 133: Motor slot 134: Motor slot 135: Motor tooth 14: First pressure plate 15: Second pressure plate 16: Rotating electromagnetic winding 2: Rotor 21: Rotor body 22, 22’: First ring 23: Rotor pole 3: Support 4: Support column

Figure 1 is a schematic diagram (three-dimensional view) of the structure of one embodiment of the stator in this invention.

Figure 2 is a three-dimensional structural diagram of the stator embodiment in this invention.

Figure 3 is a schematic diagram (front view) of the structure of the first suspension control component in the embodiment of the present invention.

Figure 4 is a two-dimensional schematic diagram of the structure of the first suspension control component in the embodiment of the present invention.

Figure 5 is a three-dimensional schematic diagram of the structure of the second suspension control component in an embodiment of the present invention.

Figure 6 is a schematic diagram (axial cross-sectional view) of the structure of one embodiment of the stator in this invention.

Figure 7 is a schematic diagram (radial section) of the structure of one embodiment of the stator in this invention.

Figure 8 is a schematic diagram (radial section) of another embodiment of the stator in this invention.

Figure 9 is a schematic diagram (radial section) of the structure of another embodiment of the stator in this invention.

Figure 10 is a schematic diagram (three-dimensional view) of the structure of one embodiment of the rotor in this invention.

Figure 11 is a three-dimensional schematic diagram of an embodiment of the magnetic levitation device in this invention.

Figure 12 is a second schematic diagram (axial cross-sectional view) of the structure of an embodiment of the magnetic levitation device in this invention.

Figure 13 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components 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 components are both 4.

Figure 14 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components 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 components are both 4.

Figure 15 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components 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 components are both 4.

Figure 16 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components 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 components are both 3.

Figure 17 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components in an embodiment of the present invention, wherein there are 4 first and 4 second stator magnetic poles and 8 permanent magnet components.

Figure 18 is a schematic diagram of the relative positions of the first and second stator magnetic poles and the permanent magnet components in an embodiment of the present invention, wherein there are 8 first and second stator magnetic poles and 4 permanent magnet components.

Figure 19 is a schematic diagram of the relative positions of the rotor, the third stator magnetic pole and the permanent magnet assembly in an embodiment of the present invention, wherein there are 8 rotor magnetic poles, 4 third stator magnetic poles and 4 permanent magnet assemblies.

Figure 20 is a schematic diagram of the relative positions of the third stator magnetic poles and permanent magnet components in an embodiment of the present invention, wherein there are 8 third stator magnetic poles and 4 permanent magnet components.

Figure 21 is a schematic diagram of the relative positions of the third stator magnetic poles and permanent magnet components in an embodiment of the present invention, wherein there are 4 third stator magnetic poles and 8 permanent magnet components.

Figure 22 is a schematic diagram (axial cross-sectional view) of an embodiment of the magnetic levitation turntable in this invention.

Figure 23 is a structural schematic diagram (axial cross-sectional view) of another embodiment of the stator in the present invention.

1: Stator

11: Permanent Magnet Device

12: First Suspension Control Component

121: First Control Component

122: Second Control Component

13: Second Suspension Control Component

14: First pressure plate

15: Second pressure plate

Claims (22)

A magnetic levitation device includes a stator and a rotor. The stator includes a permanent magnet and a first levitation control component. The first levitation control component includes a first control component and a second control component arranged in staggered layers along the axial direction. The first control component is configured to apply an axially upward levitation force to the rotor, and the second control component is configured to apply an axially downward levitation force to the rotor. In this configuration, the first control component includes multiple first stator magnetic poles uniformly arranged in a circumferential direction; the second control component includes multiple second stator magnetic poles uniformly arranged in a circumferential direction; and the permanent magnet device includes multiple permanent magnet components uniformly arranged in a circumferential direction, with each pair of radially symmetrical first stator magnetic poles positioned at a distance from the first stator magnetic poles. Equal or nearly equal magnetic flux is generated at a first air gap or at the first air gap of each first stator pole, and equal or nearly equal magnetic flux is generated at a second air gap of each pair of radially symmetrical second stator poles or at the second air gap of each second stator pole; wherein, the stator further includes a second suspension control component configured to apply radial suspension to the rotor. The buoyancy control component includes multiple third stator magnetic poles uniformly arranged in the circumferential direction. Multiple permanent magnet components are sandwiched between the first and second suspension control components, and generate equal or nearly equal magnetic flux at a third air gap of each pair of radially symmetrical third stator magnetic poles or at the third air gap of each third stator magnetic pole. According to the magnetic levitation device of claim 1, 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 magnet components are all even numbers greater than or equal to 2, or 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 magnet components are all the same and not even numbers. According to claim 2, the number of the plurality of first stator magnetic poles is the same as the number of the plurality of second stator magnetic poles and both are even numbers. According to the magnetic levitation device of claim 3, in the circumferential direction, a second stator magnetic pole is disposed between two adjacent first stator magnetic poles, and a first stator magnetic pole is disposed between two adjacent second stator magnetic poles. According to the magnetic levitation device of claim 4, 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 magnet components are all four. Each permanent magnet component is positioned opposite a first stator magnetic pole in the circumferential direction; or, each permanent magnet component is positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between an adjacent first stator magnetic pole and a second stator magnetic pole. According to the magnetic levitation device of claim 4, the number of the plurality of first stator magnetic poles and the number of the plurality of second stator magnetic poles are both 4, and the number of the plurality of permanent magnet components is 8. Each permanent magnet component is positioned opposite a first stator magnetic pole in the circumferential direction, and each permanent magnet component is positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between an adjacent first stator magnetic pole and a second stator magnetic pole. According to the magnetic levitation device of claim 4, the number of the plurality of first stator magnetic poles and the number of the plurality of second stator magnetic poles are both 8, and the number of the plurality of permanent magnet components is 4. Each permanent magnet component is positioned opposite a first stator magnetic pole in the circumferential direction, or each permanent magnet component is positioned opposite a second stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between an adjacent first stator magnetic pole and a second stator magnetic pole. According to claim 3, in the magnetic levitation device, each first stator pole is disposed corresponding to a second stator pole and at least partially overlaps in the axial direction. According to the magnetic levitation device of claim 1, the number of the plurality of third stator magnetic poles and the number of the plurality of permanent magnet components are both four, and each permanent magnet component is positioned opposite a third stator magnetic pole in the circumferential direction; or, in the circumferential direction, each permanent magnet component is equidistantly disposed between two adjacent third stator magnetic poles. According to claim 9, the magnetic levitation device has a first electromagnetic winding on the first stator pole, a second electromagnetic winding on the second stator pole, and a third electromagnetic winding on the third stator pole. According to the magnetic levitation device of claim 10, each third stator magnetic pole has multiple motor slots on the side facing the rotor, a motor tooth is formed between two adjacent motor slots, and a motor slot gap is formed between two adjacent third stator magnetic poles, wherein the motor slot gap is configured as a motor slot. According to the magnetic levitation device of claim 1, the rotor includes a rotor body, a first annular rim and a second annular rim extending from the rotor body to the stator, a first air gap is formed between the first stator magnetic pole and the first annular rim, and a second air gap is formed between the second stator magnetic pole and the first annular rim; the second annular rim is equally spaced to form a plurality of rotor magnetic poles, and a third air gap is formed between the rotor magnetic poles and the third stator magnetic pole. According to claim 12, the number of rotor poles is an even number greater than or equal to 2, or the number of rotor poles is the same as the number of third stator poles and is not an even number. According to claim 13, the magnetic levitation device has 8 rotor poles and 4 third stator poles. According to the magnetic levitation device of claim 1, the first control component further includes a ring-shaped first magnetic substrate, wherein the plurality of first stator magnetic poles are formed on the first magnetic substrate and protrude toward the rotor; the second control component further includes a ring-shaped second magnetic substrate, wherein the plurality of second stator magnetic poles are formed on the second magnetic substrate and protrude toward the rotor; the second levitation control component further includes a ring-shaped third magnetic substrate, wherein the plurality of third stator magnetic poles are formed on the third magnetic substrate and protrude toward the rotor; the third magnetic substrate, the permanent magnet component, the first magnetic substrate, and the second magnetic substrate are sequentially stacked together along the axial direction. The magnetic levitation device according to claim 15, wherein the permanent magnet component includes at least one axially magnetized permanent magnet. According to the magnetic levitation device of claim 15, each permanent magnet component includes multiple permanent magnets arranged in the same radial plane, the distance between two adjacent permanent magnets being the same or nearly the same, the multiple permanent magnets being arranged in a straight line in the radial plane, and the line connecting the center of the permanent magnet component and the projection point of the rotation axis of the rotor in the radial plane being perpendicular or nearly perpendicular to the straight line. According to the magnetic levitation device of claim 15, each permanent magnet component includes multiple permanent magnets arranged in the same radial plane, the distance between two adjacent permanent magnets being the same or nearly the same, the multiple permanent magnets being arranged in an arc in the radial plane, and the projection point of the rotation axis of the rotor in the radial plane being the same or nearly the same as the distance between each of the permanent magnets. According to claim 18, in the circumferential direction, the distance between the outermost permanent magnets of two adjacent permanent magnet components is the same as or nearly the same as the distance between two adjacent permanent magnets of the permanent magnet components. According to claim 16, the magnetic levitation device includes a support block with a fixing groove formed on the support block corresponding to each permanent magnet, wherein the permanent magnet is positioned in the corresponding fixing groove. According to the magnetic levitation device of claim 15, the stator further includes a plurality of first pressure plates and a plurality of second pressure plates, the plurality of first pressure plates being disposed on the outer side of the third magnetic substrate, the plurality of second pressure plates being disposed on the outer side of the second magnetic substrate, and the plurality of first pressure plates and the plurality of second pressure plates being fastened together by a fastener. A magnetic levitation turntable, comprising a carrier and a magnetic levitation device as described in any one of claims 1-21, wherein the rotor supports and positions the carrier via a plurality of support columns.