Methods and systems for controllably moving multiple moveable stages in a displacement device

Patent metadata

Field	Value
Publication number	US-10348178-B2
Application number	US-201815881719-A
Country	US
Kind code	B2
Filing date	Jan 26, 2018
Priority date	Jun 7, 2014
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

Aspects of the invention provide methods and systems for moving a plurality of moveable stages relative to a stator. The stator comprises a plurality of coils shaped to provide pluralities of coil trace groups where each coil trace group comprises a corresponding plurality of generally linearly elongated coil traces which extend across a stator tile. Each moveable stage comprises a plurality of magnet arrays. Methods and apparatus are provided for moving the moveable stages relative to the stator, where a magnet array from a first moveable stage and a magnet array from a second moveable stage both overlap a shared group of coil traces. For at least a portion of the time that the magnet arrays from the first and second moveable stages overlap the shared group of coil traces, currents are controllably driven in the shared coil trace group based on the positions of both the first and second moveable stages. The positions of the first and second moveable stages may be ascertained by feedback.

First claim

What is claimed is:

1. A method for moving a plurality of moveable stages relative to a stator, the method comprising:
providing a stator comprising one or more stator tiles, each stator tile comprising:
an x-trace layer comprising a plurality of electrically conductive x-traces which extend in a stator-x direction across the stator tile and into which currents may be independently driven;
a y-trace layer comprising a plurality of electrically conductive y-traces which extend in a stator-y direction across the stator tile and into which currents may be independently driven;
the x-trace layer and the y-trace layer overlapping one another in a stator-z direction;
the stator-x direction and the stator-y direction non-parallel to one another;

providing a first moveable stage comprising:
a first first magnet array comprising a plurality of first first magnetization segments; and
a first second magnet array comprising a plurality of first second magnetization segments;

providing a second moveable stage comprising:
a second first magnet array comprising a plurality of second first magnetization segments; and
a second second magnet array comprising a plurality of second second magnetization segments; and

driving current in one or more of the x-traces and the y-traces to thereby move at least one of the first moveable stage and the second moveable stage by interaction of magnetic field associated with the current and the at least one of the first and second moveable stages to a queuing formation wherein:
at least a portion of the first first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile.

2. A method according to claim 1 wherein, in the queuing formation, at least a portion of the first second magnet array is non-overlapping in the stator-y direction with each magnet array of each other stage on the first stator tile.

3. A method according to claim 1 wherein, in the queuing formation, the first first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile.

4. A method according to claim 1 wherein, in the queuing formation:
the first first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile; and
the first second magnet array is non-overlapping in the stator-y direction with each magnet array of each other stage on the first stator tile.

5. A method according to claim 1 comprising:
providing a third moveable stage comprising a third magnet array comprising a plurality of third magnetization segments linearly elongated in a stage-x direction, each third magnetization segment has a corresponding magnetization direction orthogonal to the stage-x direction and at least two of the third magnetization segments have magnetization directions that are different from one another;
providing a fourth moveable stage comprising a fourth magnet array comprising a plurality of fourth magnetization segments linearly elongated in a stage-x direction, each fourth magnetization segment has a corresponding magnetization direction orthogonal to the stage-x direction and at least two of the fourth magnetization segments have magnetization directions that are different from one another;
wherein the first moveable stage comprises a first third magnet array comprising a plurality of first third magnetization segments and wherein, in the queuing formation, at least a portion of the first third magnet array is non-overlapping in the stator-x direction with each magnet array comprising magnetization segments that are linearly elongated in the stage-x direction of each other stage on the first stator tile.

6. A method according to claim 4 comprising:
providing a third moveable stage comprising a third magnet array comprising a plurality of third magnetization segments linearly elongated in a stage-x direction, each third magnetization segment has a corresponding magnetization direction orthogonal to the stage-x direction and at least two of the third magnetization segments have magnetization directions that are different from one another;
providing a fourth moveable stage comprising a fourth magnet array comprising a plurality of fourth magnetization segments linearly elongated in a stage-x direction, each fourth magnetization segment has a corresponding magnetization direction orthogonal to the stage-x direction and at least two of the fourth magnetization segments have magnetization directions that are different from one another;
wherein the first moveable stage comprises a first third magnet array comprising a plurality of first third magnetization segments and wherein, in the queuing formation, the first third magnet array is non-overlapping in the stator-x direction with each magnet array comprising magnetization segments that are linearly elongated in the stage-x direction of each other stage on the first stator tile.

7. A method according to claim 1 comprising:
providing a third moveable stage comprising:
a third first magnet array comprising a plurality of third first magnetization segments; and
a third second magnet array comprising a plurality of third second magnetization segments; and

wherein driving current in one or more of the x-traces and the y-traces comprises:
moving at least one of the first, second and third moveable stages by interaction of the magnetic field associated with the current and the at least one of the first, second and third moveable stages to the queuing formation and wherein, in the queuing formation:
at least a portion of the third first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile.

8. A method according to claim 7 wherein, in the queuing formation, at least a portion of the third second magnet array is non-overlapping in the stator-y direction with each magnet array of each other stage on the first stator tile.

9. A method according to claim 8 comprising:
providing a fourth moveable stage comprising:
a fourth first magnet array comprising a plurality of fourth first magnetization segments; and
a fourth second magnet array comprising a plurality of fourth second magnetization segments; and

wherein driving current in one or more of the x-traces and the y-traces comprises:
moving at least one of the first, second, third and fourth moveable stages by interaction of the magnetic field associated with the current and the at least one of the first, second, third and fourth moveable stages to the queuing formation and wherein, in the queuing formation:
at least a portion of the fourth first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile.

10. A method according to claim 9 wherein, in the queuing formation, at least a portion of the fourth second magnet array is non-overlapping in the stator-y direction with each magnet array of each other stage on the first stator tile.

11. A method according to claim 10 wherein, in the queuing formation:
the third first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile;
the third second magnet array is non-overlapping in the stator-y direction with each magnet array of each other stage on the first stator tile;
the fourth first magnet array is non-overlapping in the stator-x direction with each magnet array of each other stage on the first stator tile; and
the fourth second magnet array is non-overlapping in the stator-y direction with each magnet array of ea

Assignees

• Univ British Columbia

Inventors

• Lu Xiaodong

Classifications

• H02K2201/18

  Machines moving with multiple degrees of freedom · CPC title

• H02K16/02

  Machines with one stator and two {or more} rotors · CPC title

• H02P25/066

  of the stepping type · CPC title

• H02K41/03

  Synchronous motors; Motors moving step by step; Reluctance motors (H02K41/035 takes precedence) · CPC title

• H02K41/02

  Linear motors; Sectional motors · CPC title