Magnetic suspension device and semiconductor processing apparatus
View Patent ↗A magnetic levitation device and a semiconductor processing equipment are provided. The magnetic levitation device includes a rotor and a stator. The stator includes at least three magnetic stator substrates, a permanent magnet and a guiding magnet. The at least three magnetic stator substrates are spaced apart from each other to define at least two gaps, the permanent magnet and the guiding magnet are alternately arranged in the at least two gaps; the at least three magnetic stator substrates include a first magnetic stator substrate, a protrusion and a magnetic levitation coil of the first magnetic stator substrate apply an upward force along the axial direction of the stator on the rotor, and a ratio of the number of the first magnetic stator substrate(s) to the total number of the at least three magnetic stator substrates is greater than or equal to 50%.
1 . A magnetic levitation device, comprising:
a rotor; and
a stator, wherein the stator surrounds the rotor, or, the rotor surrounds the stator,
wherein:
the stator comprises at least three magnetic stator substrates, a permanent magnet and a guiding magnet, the at least three magnetic stator substrates are spaced apart from each other in an axial direction of the stator to define at least two gaps in the axial direction of the stator, the permanent magnet and the guiding magnet are alternately arranged in the at least two gaps in the axial direction of the stator;
each of the at least three magnetic stator substrates comprises a substrate body and a protrusion connected with the substrate body, the protrusion is protruded from the permanent magnet and the guiding magnet towards the rotor, and a magnetic levitation coil is wound on the protrusion; and
the at least three magnetic stator substrates comprise a first magnetic stator substrate, wherein a protrusion and a magnetic levitation coil of the first magnetic stator substrate apply an upward force along the axial direction of the stator on the rotor, and a ratio of the number of the first magnetic stator substrate(s) to the total number of the at least three magnetic stator substrates is greater than or equal to 50%,
wherein each of the at least three magnetic stator substrates comprise a plurality of the protrusions, the number of the first magnetic stator substrate(s) is at least two.
2 . The magnetic levitation device according to claim 1 , wherein the at least three magnetic stator substrates further comprise a second magnetic stator substrate, a protrusion and a magnetic levitation coil of the second magnetic stator substrate apply a downward force along the axial direction of the stator on the rotor, and the number of the first magnetic stator substrate(s) is greater than or equal to the number of the second magnetic stator substrate(s).
3 . The magnetic levitation device according to claim 2 , wherein:
the rotor comprises a rotor body and at least three flanges protruded from the rotor body towards the stator;
the number of the at least three magnetic stator substrates is equal to the number of the at least three flanges, and the at least three magnetic stator substrates are in one-to-one correspondence with the at least three flanges; and
the at least three flanges comprise a first flange corresponding to the first magnetic stator substrate, and a center line of the protrusion of the first magnetic stator substrate in the axial direction of the stator is higher than a center line of the first flange in the axial direction of the stator.
4 . The magnetic levitation device according to claim 3 , wherein:
the center line of the protrusion of the first magnetic stator substrate in the axial direction is higher than the center line of the first flange in the axial direction comprises one of the following situations:
(i) in the axial direction of the stator, an upper surface of the protrusion of the first magnetic stator substrate is higher than an upper surface of the first flange, and a lower surface of the protrusion of the first magnetic stator substrate is higher than the upper surface of the first flange or is at the same height as the upper surface of the first flange;
(ii) in the axial direction of the stator, the upper surface of the protrusion of the first magnetic stator substrate is higher than the upper surface of the first flange or is at the same height as the upper surface of the first flange, and a lower surface of the first flange is lower than the lower surface of the protrusion of the first magnetic stator substrate, and the upper surface of the first flange is higher than the lower surface of the protrusion of the first magnetic stator substrate;
(iii) in the axial direction of the stator, the upper surface of the protrusion of the first magnetic stator substrate is higher than the upper surface of the first flange, and the lower surface of the first flange is higher than the lower surface of the protrusion of the first magnetic stator substrate or is at the same height as the lower surface of the protrusion of the first magnetic stator substrate; and
(iv) in the axial direction of the stator, the upper surface of the protrusion of the first magnetic stator substrate is at the same height as the upper surface of the first flange or is lower than the upper surface of the first flange, and the lower surface of the protrusion of the first magnetic stator substrate is higher than the lower surface of the first flange.
5 . The magnetic levitation device according to claim 4 , wherein in the situation (ii), a distance between the upper surface of the protrusion of the first magnetic stator substrate and the upper surface of the first flange is H, and H≤⅘Ha, wherein Ha is a size of the first flange in the axial direction of the stator.
6 . The magnetic levitation device according to claim 3 , wherein:
the at least three flanges comprise a second flange corresponding to the second magnetic stator substrate, and a center line of the second flange in the axial direction of the stator is higher than a center line of the protrusion of the second magnetic stator substrate in the axial direction of the stator.
7 . The magnetic levitation device according to claim 6 , wherein:
the center line of the second flange in the axial direction is higher than the center line of the protrusion of the second magnetic stator substrate in the axial direction comprises one of the following situations:
(i) in the axial direction of the stator, an upper surface of the second flange is higher than an upper surface of the protrusion of the second magnetic stator substrate, and a lower surface of the second flange is higher than the upper surface of the protrusion of the second magnetic stator substrate or is at the same height as the upper surface of the protrusion of the second magnetic stator substrate;
(ii) in the axial direction of the stator, the upper surface of the second flange is higher than the upper surface of the protrusion of the second magnetic stator substrate or is at the same height as the upper surface of the protrusion of the second magnetic stator substrate, and a lower surface of the protrusion of the second magnetic stator substrate is lower than the lower surface of the second flange, and the lower surface of the second flange is lower than the upper surface of the protrusion of the second magnetic stator substrate;
(iii) in the axial direction of the stator, the upper surface of the second flange is higher than the upper surface of the protrusion of the second magnetic stator substrate, and the lower surface of the protrusion of the second magnetic stator substrate is higher than the lower surface of the second flange or is at the same height as the lower surface of the second flange; and
(iv) in the axial direction of the stator, the upper surface of the second flange is at the same height as the upper surface of the protrusion of the second magnetic stator substrate or is lower than the upper surface of the protrusion of the second magnetic stator substrate, and the lower surface of the second flange is higher than the lower surface of the protrusion of the second magnetic stator substrate.
8 . The magnetic levitation device according to claim 7 , wherein:
in the situation (ii), a distance between the upper surface of the second flange and the upper surface of the protrusion of the second magnetic stator substrate is H and H≤⅘Ha, wherein Ha is a size of the second flange in the axial direction of the stator.
9 . The magnetic levitation device according to claim 3 , wherein:
a distance between each of the at least three magnetic stator substrates and a corresponding flange in a radial direction of the stator is L; and
a size of each of the at least two gaps in the axial direction of the stator is at least three times as great as L.
10 . The magnetic levitation device according to claim 3 , wherein a distance between each of the at least three magnetic stator substrates and a corresponding flange in a radial direction of the stator is L and L≤Ha, wherein Ha is a size of the flange in the axial direction of the stator.
11 . The magnetic levitation device according to claim 2 , wherein:
the number of the second magnetic stator substrate(s) is at least one.
12 . The magnetic levitation device according to claim 1 , wherein:
the number of the at least three magnetic stator substrates is four or more than four; and
in the axial direction of the stator, opposite surfaces of two adjacent permanent magnets have the same magnetism.
13 . The magnetic levitation device according to claim 1 , wherein:
at least one magnetic stator substrate of the at least three magnetic stator substrates comprises a plurality of teeth, the plurality of teeth are connected with the substrate body and are protruded from the permanent magnet and the guiding magnet towards the rotor, and a magnetic rotating coil is wound on each of the plurality of teeth;
the magnetic levitation coil is arranged farther from the rotor than the magnetic rotating coil; and
the plurality of teeth are arranged at an end of the protrusion facing towards the rotor.
14 . The magnetic levitation device according to claim 13 , wherein the number of the at least one magnetic stator substrate is one, and the one magnetic stator substrate is a magnetic stator substrate located at an uppermost layer or a lowermost layer in the axial direction of the stator among the at least three magnetic stator substrates; or the number of the at least one magnetic stator substrate is one, and the one magnetic stator substrate is a magnetic stator substrate located at a middle layer in the axial direction of the stator among the at least three magnetic stator substrates.
15 . The magnetic levitation device according to claim 13 , wherein:
the number of the at least one magnetic stator substrate is an even number, and the even number of magnetic stator substrates are symmetrically arranged with relative to a central line of the stator in the axial direction of the stator; or
the number of the at least one magnetic stator substrate is an odd number greater than 1, wherein one of the at least one magnetic stator substrate is the magnetic stator substrate located at a middle layer in the axial direction of the stator among the at least three magnetic stator substrates, and the other magnetic stator substrates of the at least one magnetic stator substrate are symmetrically arranged with relative to a central line of the stator in the axial direction of the stator.
16 . The magnetic levitation device according to claim 13 , wherein:
the rotor comprises a rotor body and at least three flanges protruded from the rotor body towards the stator;
the number of the at least three magnetic stator substrates is equal to the number of the at least three flanges, and the at least three magnetic stator substrates are in one-to-one correspondence with the at least three flanges; and
an end of the flange corresponding to the at least one magnetic stator substrate that faces towards the at least one magnetic stator substrate has a plurality of teeth.
17 . The magnetic levitation device according to claim 1 , wherein among at least two gaps, the permanent magnet is arranged in an odd-numbered gap counting from top to bottom in the axial direction of the stator, and the guiding magnet is arranged in an even-numbered gap counting from top to bottom in the axial direction of the stator.
18 . The magnetic levitation device according to claim 1 , wherein:
the permanent magnet is in direct contact with the magnetic stator substrate adjacent thereto, or the permanent magnet is spaced apart from the magnetic stator substrate adjacent thereto by an air gap, or a guiding magnet piece is inserted between the permanent magnet and the magnetic stator substrate adjacent thereto.
19 . The magnetic levitation device according to claim 1 , wherein:
the guiding magnet is in direct contact with the magnetic stator substrate adjacent thereto, or the guiding magnet is spaced apart from the magnetic stator substrate adjacent thereto by an air gap, or a guiding magnet piece is inserted between the guiding magnet and the magnetic stator substrate adjacent thereto.
20 . A semiconductor processing equipment, comprising a magnetic levitation device, the magnetic levitation device comprising:
a rotor; and
a stator, wherein the stator surrounds the rotor, or, the rotor surrounds the stator,
wherein:
the stator comprises at least three magnetic stator substrates, a permanent magnet and a guiding magnet, the at least three magnetic stator substrates are spaced apart from each other in an axial direction of the stator to define at least two gaps in the axial direction of the stator, the permanent magnet and the guiding magnet are alternately arranged in the at least two gaps in the axial direction of the stator;
each of the at least three magnetic stator substrates comprises a substrate body and a protrusion connected with the substrate body, the protrusion is protruded from the permanent magnet and the guiding magnet towards the rotor, and a magnetic levitation coil is wound on the protrusion; and
the at least three magnetic stator substrates comprise a first magnetic stator substrate, wherein a protrusion and a magnetic levitation coil of the first magnetic stator substrate apply an upward force along the axial direction of the stator on the rotor, and a ratio of the number of the first magnetic stator substrate(s) to the total number of the at least three magnetic stator substrates is greater than or equal to 50%,
wherein each of the at least three magnetic stator substrates comprise a plurality of the protrusions, the number of the first magnetic stator substrate(s) is at least two.