Displacement devices and methods for fabrication, use and control of same

Patent metadata

Field	Value
Publication number	US-2022166301-A1
Application number	US-202117543671-A
Country	US
Kind code	A1
Filing date	Dec 6, 2021
Priority date	Oct 27, 2011
Publication date	May 26, 2022
Grant date	—

Abstract

Displacement devices comprise a stator and a moveable stage. The stator comprises a plurality of coils shaped to provide pluralities of generally linearly elongated coil traces in one or more layers. Layers of coils may overlap in the Z-direction. The moveable stage comprises a plurality of magnet arrays. Each magnet array may comprise a plurality of magnetization segments generally linearly elongated in a corresponding direction. Each magnetization segment has a magnetization direction generally orthogonal to the direction in which it is elongated and at least two of the magnetization directions are different from one another. One or more amplifiers may be connected to selectively drive current in the coil traces and to thereby effect relative movement between the stator and the moveable stage.

First claim

1 - 20 . (canceled)

21 . A displacement device comprising:
a stator comprising:
a plurality of radially-oriented first coils distributed over a first layer at a corresponding first stator Z-location, each of the plurality of first coils generally linearly elongated in a corresponding first radial stator direction in the first layer;
wherein each first radial stator direction extends from a first point;
a moveable stage comprising:
a first magnet array comprising a plurality of spaced apart first magnetization segments, each first magnetization segment generally linearly elongated in a corresponding first stage direction, each first magnetization segment having a first magnetization direction generally orthogonal to its respective direction of elongation and at least two of the first magnetization segments having first magnetization directions that are different from one another;
one or more amplifiers connected to drive current in the plurality of coils and to thereby effect relative movement between the stator and the moveable stage.

22 . A displacement device according to claim 21 wherein the plurality of spaced apart first magnetization segments are angularly spaced apart and each corresponding first stage direction is a corresponding first radial stage direction, wherein each first radial stage direction extends from a second point.

23 . A displacement device according to claim 22 wherein the first magnet array has an angular spatial magnetization period λ and the number of spatial magnetic periods λ in the first magnet array is a positive integer number N m .

24 . A displacement device according to claim 23 wherein N m is equal to 8 and an angle subtended by each spatial magnetic period is 45°.

25 . A displacement device according to claim 22 wherein the first magnet array has an angular spatial magnetization period λ and the number of spatial magnetic periods λ in the first magnet array is (N m +0.5) where N m is a positive integer number.

26 . A displacement device according to claim 21 wherein the current in the plurality of first coils is capable of imparting force on the first magnet array in both circumferential directions and in a stage Z-direction orthogonal to each of the first radial stage directions and the circumferential directions.

27 . A displacement device according to claim 26 wherein the first coils are divided into a plurality of groups wherein:
at least two groups of the plurality of groups impart stage Z-direction and stage Y-direction forces on the magnet array;
at least two other groups of the plurality of groups impart stage Z-direction and stage X-direction forces on the magnet array;
the X-direction is generally orthogonal to the Y-direction; and
the stage Z-direction is generally orthogonal to the X-direction and the Y-direction.

28 . A displacement device according to claim 21 , wherein the stator comprises a plurality of sensor heads which interact with one or more corresponding sensor targets on the moveable stage to sense a rotary orientation of the moveable stage about a stator Z-direction axis and translational positions of the moveable stage.

29 . A displacement device according to claim 28 , the plurality of sensor heads comprise encoder read heads and the corresponding sensor targets comprises encoder disks.

30 . A displacement device according to claim 22 , wherein the moveable stage comprises:
a second magnet array comprising a plurality of angularly spaced apart second magnetization segments, each second magnetization segment generally linearly elongated in a second radial stage direction, each second magnetization segment having a second magnetization direction generally orthogonal to its respective direction of elongation and at least two of the second magnetization segments having second magnetization directions that are different from one another; a third magnet array comprising a plurality of angularly spaced apart third magnetization segments, each third magnetization segment generally linearly elongated in a third radial stage direction, each third magnetization segment having a third magnetization direction generally orthogonal to its respective direction of elongation and at least two of the third magnetization segments having third magnetization directions that are different from one another; a fourth magnet array comprising a plurality of angularly spaced apart fourth magnetization segments, each fourth magnetization segment generally linearly elongated in a fourth radial stage direction, each fourth magnetization segment having a fourth magnetization direction generally orthogonal to its respective direction of elongation and at least two of the fourth magnetization segments having fourth magnetization directions that are different from one another; wherein each second radial stator direction extends from a third point, each third radial stator direction extends from a fourth point and each fourth radial stator direction extends from a fifth point; and wherein the first, second, third and fourth magnet arrays are angularly spaced apart from one another.

31 . A displacement device according to claim 30 , wherein the first, second, third and fourth magnet arrays are angularly spaced apart from one another by spaces.

32 . A displacement device according to claim 30 , a number of spatial magnetic periods λ in each of the first, second, third and fourth magnet arrays is a positive integer number N m , such that an angle subtended by each of the first, second, third and fourth magnet arrays is W m =N m λ.

33 . A displacement device according to claim 21 wherein:
the stator is circular or annular; and
the first point comprises a center of the stator.

34 . A displacement device according to claim 33 wherein the first plurality of radially-oriented coils are angularly spaced apart over a 360° range around the center of the stator.

35 . A displacement device according to claim 22 wherein:
the moveable stage is circular or annular;
the second point comprises a center of the moveable stage.

36 . A displacement device according to claim 35 wherein the plurality of first magnetization segments are angularly spaced apart over a 360° range around the center of the moveable stage.

37 . A displacement device according to claim 22 wherein a first pair of first magnetization segments of the plurality of first magnetization segments each have angular widths that are half the size of angular widths of at least one magnetization segment of the plurality of first magnetization segments.

38 . A displacement device according to claim 21 , the stator comprising:
a plurality of second coils distributed over a second layer at a corresponding second stator Z-location, each of the plurality of second coils generally linearly elongated; and wherein the first and second layers overlap one another in a stator Z-direction in a working region.

39 . A displacement device according to claim 21 , the stator comprising:
a plurality of second radially-oriented coils distributed over a second layer at a corresponding second stator Z-location, each of the plurality of second coils generally linearly elongated in a corresponding second radial stator direction in the second layer wherein each second radial stator direction extends from a sixth point; wherein the first and second layers overlap one another in a stator Z-direction in a working region; and wherein the plurality of first coils of the first layer are spatially offset from the plura

Assignees

• Univ British Columbia

Inventors

• Lu Xiaodong
• Usman Irfan-Ur-Rab

Classifications

• H10P72/00

  Handling or holding of wafers, substrates or devices during manufacture or treatment thereof · CPC title

• H02K21/24 Primary

  with magnets axially facing the armatures, e.g. hub-type cycle dynamos · CPC title

• H02K41/031 Primary

  of the permanent magnet type · CPC title

• H02K2201/18

  Machines moving with multiple degrees of freedom · CPC title

• H02K7/09

  with magnetic bearings · CPC title