Magnetic actuator

Patent metadata

Field	Value
Publication number	US-10690906-B2
Application number	US-201113307749-A
Country	US
Kind code	B2
Filing date	Nov 30, 2011
Priority date	Dec 8, 2010
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A magnetic actuator includes: a plate having a main plane of extent and mounted rotatably about at least one first axis of rotation which is parallel to the main plane of extent, the plate having at least one conductor loop parallel to the main plane of extent; a magnetic bracket situated beneath the plate and having a U-shaped magnetic flux conducting rail and a hard magnet whose magnetization is perpendicular to the U-shaped opening, the magnetic bracket and the plate being aligned with one another in such a way that the opening in the magnetic bracket points toward the main plane of extent of the plate, the U-shaped magnetic flux conducting rail having a main direction of extent parallel to the first axis of rotation, and the plate being deflectable about the at least one axis of rotation by energizing the at least one conductor loop.

First claim

What is claimed is:

1. A magnetic actuator, comprising:
a plate having one main plane of extent and mounted rotatably about at least one first axis of rotation which is parallel to the main plane of extent, the plate having at least one conductor loop parallel to the main plane of extent; and
a magnetic bracket situated beneath the plate, the magnetic bracket having a U-shaped magnetic flux conducting rail and a hard magnet whose magnetization is perpendicular to the U-shaped opening;
wherein the hard magnet is disposed inside the U-shaped opening, a bottom surface of the hard magnet being above and in direct contact with a bottom surface of the U-shaped opening,
wherein the magnetic bracket and the plate are aligned with one another in such a way that the opening in the magnetic bracket points toward the main plane of extent of the plate, and wherein the U-shaped magnetic flux conducting rail has a main direction of extent which is parallel to the first axis of rotation, and wherein the plate is deflectable about the first axis of rotation by energizing the at least one conductor loop,
wherein the plate has (i) two conductor loops parallel to the main plane of extent, and (ii) two surface areas in the main plane of extent separated by the first axis of rotation,
wherein in the plate one of the conductor loops is situated only in one of the surface areas and the other conductor loop is situated only in the other surface area,
wherein the two conductor loops are displaced from one another only in a single direction that is perpendicular to the first axis of rotation,
wherein each of the two conductor loops have a length that intersects a second axis that is perpendicular to the first axis of rotation,
wherein the two surface areas are confined to edge areas of the plate,
wherein the plate has a first side that is longer than a second side,
wherein the first side is parallel to the main direction of extent,
wherein the magnetic bracket produces a magnetic field that is coplanar with the main plane of extent in which the two conductor loops are located,
wherein a Lorentz-force generated by the magnetic field is perpendicular to the main plane of extent in which the two conductor loops are located,
wherein when the plate is at rest the plate is coplanar with an xy plane,
wherein the U-shaped magnetic flux conducting rail causes the magnetic field to include a plurality of field line components that run parallel to each other and to the second axis within the xy plane, and
wherein a torque about the first axis of rotation is generated on the plate by energizing the two conductor loops in opposite directions.

2. The magnetic actuator as recited in claim 1 , wherein the magnetic bracket has a hard magnet, and wherein one of a whole-area or a structured flux conductor layer is applied to an open side of the hard magnet.

3. The magnetic actuator as recited in claim 1 , wherein a shield fixed by a spacer is situated opposite the opening in the magnetic bracket to reduce a magnetic stray field toward an open side of the magnetic bracket.

4. The magnetic actuator as recited in claim 1 , wherein the plate is mounted rotatably about the first axis of rotation via one of a torsion spring, a meandering spring, a bending spring, or a progressive spring.

5. The magnetic actuator as recited in claim 1 , wherein the plate is connected to a central spring suspension which allows tilting of the plate in at least one direction.

6. The magnetic actuator as recited in claim 1 , wherein the conductor loops are disposed on a surface of the plate that faces away from the hard magnet.

7. The magnetic actuator as recited in claim 1 , wherein each of the conductor loops is located on the plate at a maximum distance from the first axis of rotation.

8. The magnetic actuator as recited in claim 1 , wherein the two conductor loops are electrically disconnected from one another in the plate.

9. The magnetic actuator as recited in claim 1 , wherein a center region of the plate that is traversed by a longitudinal axis of the plate is outside a region of the plate enclosed by a first of the conductor loops and is outside a region of the plate enclosed by a second of the conductor loops.

10. The magnetic actuator as recited in claim 1 , wherein a clearance exists between a top surface of the hard magnet and a bottom surface of the plate, a height of the clearance being delimited by the top surface of the hard magnet and the bottom surface of the plate.

11. The magnetic actuator as recited in claim 1 , wherein a direction of the magnetization of the hard magnet is perpendicular to the plate.

12. The magnetic actuator as recited in claim 1 , wherein a flux-conducting material that is different than a material of the hard magnet is disposed on a top surface of the magnet.

13. The magnetic actuator as recited in claim 1 , wherein each of the two conductor loops includes a first linear extension that is parallel to the main direction of extent and is longer than any other linear extension of the conductor loop of the two conductor loops to which the first linear extension respectively belongs.

14. The magnetic actuator as recited in claim 1 , wherein:
each of the two conductor loops includes a pair of parallel segments that extend parallel to the first axis,
in each of the two conductor loops, a first one of the parallel segments is closer to the first axis than is a second one of the parallel segments, and
in each of the two conductor loops a distance between the first segment and the segment is smaller than a distance of the first segment to the first axis.

15. A micromirror system, comprising:
a magnetic actuator including:
a plate having one main plane of extent and mounted rotatably about at least one first axis of rotation which is parallel to the main plane of extent, the plate having at least one conductor loop parallel to the main plane of extent; and
a magnetic bracket situated beneath the plate, the magnetic bracket having a U-shaped magnetic flux conducting rail and a hard magnet whose magnetization is perpendicular to the U-shaped opening;
wherein the hard magnet is disposed inside the U-shaped opening, a bottom surface of the hard magnet being above and in direct contact with a bottom surface of the U-shaped opening,
wherein the magnetic bracket and the plate are aligned with one another in such a way that the opening in the magnetic bracket points toward the main plane of extent of the plate, and wherein the U-shaped magnetic flux conducting rail has a main direction of extent which is parallel to the first axis of rotation, and wherein the plate is deflectable about the first axis of rotation by energizing the at least one conductor loop, and wherein the rotatably mounted plate is provided with one of a reflective surface, a mirror element, or a reflective material on a side of the plate facing away from the opening in the magnetic bracket,
wherein the plate has (i) two conductor loops parallel to the main plane of extent, and (ii) two surface areas in the main plane of extent separated by the first axis of rotation,
wherein in the plate one of the conductor loops is situated only in one of the surface areas and the other conductor loop is situated only in the other surface area,
wherein the two conductor loops are displaced from one another only in a single direction that is perpendicular to the first axis of rotation,
wherein each of the two conductor loops have a length that intersects a second axis that is perpendicular to the first axis of rotation,
wherein the two surface areas are confined to edge areas of the

Assignees

• Pinter Stefan
• Muchow Joerg
• Schatz Frank
• Bosch Gmbh Robert

Inventors

• Pinter Stefan
• Muchow Joerg
• Schatz Frank

Classifications

• H02K41/0354

  Lorentz force motors, e.g. voice coil motors · CPC title

• H02K33/18

  with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets · CPC title

• G02B26/105

  with one or more pivoting mirrors or galvano-mirrors (G02B26/101 takes precedence) · CPC title

• G02B26/085 Primary

  the reflecting means being moved or deformed by electromagnetic means · CPC title