Micromechanical devices with mechanical actuators

Patent metadata

Field	Value
Publication number	US-11639718-B2
Application number	US-201916507932-A
Country	US
Kind code	B2
Filing date	Jul 10, 2019
Priority date	Jan 10, 2017
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

A planar micromechanical actuator suspended on opposing suspension zones including a neutral axis between the opposing suspension zones, first to fourth segments into which the planar micromechanical actuator is segmented between the opposing suspension zones, each including a first electrode and a second electrode which form a capacitor and are isolatedly affixed to each other at opposite ends of the respective segment along a direction between the opposing suspension zones so as to form a gap between the first and second electrode along a thickness direction, the gap being offset to the neutral axis along the thickness direction, and wherein the first to fourth segments are configured such that the planar micromechanical actuator deflects into the thickness direction by the first and fourth segment bending into the thickness direction and the second and third segments bending contrary to the thickness direction upon a voltage being applied to the first and second electrodes of the first to fourth segments.

First claim

The invention claimed is:

1. A planar micromechanical actuator suspended on opposing suspension zones comprising:
a neutral axis between the opposing suspension zones,
first to fourth segments into which the planar micromechanical actuator is segmented between the opposing suspension zones, each comprising a first electrode and a second electrode which form a capacitor and are isolatedly affixed to each other at opposite ends of the respective segment along a direction between the opposing suspension zones so as to form a gap between the first and second electrode along a thickness direction, the gap being offset to the neutral axis along the thickness direction, and
wherein the first to fourth segments are configured such that the planar micromechanical actuator deflects into the thickness direction by the first and fourth segment bending into the thickness direction and the second and third segments bending contrary to the thickness direction upon a voltage being applied to the first and second electrodes of the first to fourth segments.

2. The planar micromechanical actuator according to claim 1 , wherein the planar micromechanical actuator comprises exactly four segments.

3. The planar micromechanical actuator according to claim 1 , wherein the gaps of the first and fourth segment are arranged on a first side of the neutral axis, and wherein the gaps of the second and third segment are arranged on a second side of the neutral axis, wherein the second side opposes the first side.

4. The planar micromechanical actuator according to claim 1 , wherein the first and second electrodes of the respective segment are isolatedly affixed to each other by spacers.

5. The planar micromechanical actuator according to claim 4 , wherein the spacers are formed, at least partially, from an insulating material.

6. The planar micromechanical actuator according to claim 1 , wherein the gaps of the respective segments, neglecting the affixation, are of planar shape.

7. The planar micromechanical actuator according to claim 1 , wherein each segment comprises a third electrode arranged along the second electrode on an opposite side of the neutral axis to the first electrode, and wherein for each segment the third electrode is isolatedly affixed to the second electrode at opposite ends of the respective segment along a direction between the opposing suspension zones so as to form a second gap in a direction opposite to the thickness direction between the third electrode and the second electrode.

8. A planar micromechanical actuator suspended on opposing suspension zones comprising:
a first, second and third electrode, wherein the second electrode is sandwiched between the first and third electrodes,
wherein the planar micromechanical actuator is segmented between the opposing suspension zones into a sequence of segments, wherein for each segment the first electrode and third electrode are isolatedly affixed to the second electrode at opposite ends of the respective segment along a direction between the opposing suspension zones,
wherein the sequence of segments is subdivided into a first to fourth subsequence of segments, each subsequence comprising one or more segments,
wherein in each segment of the first and fourth subsequences, the first, second and third electrodes are shaped to bulge towards a first direction and bend upon application of a voltage between the first and third electrodes on the one hand and the second electrode on the other hand into a second direction opposite to the first direction, and
wherein in each segment of the second and third subsequences, the first, second and third electrodes are shaped to bulge towards the second direction and bend upon application of the voltage between the first and third electrodes on the one hand and the second electrode on the other hand into the first direction,
wherein the first subsequence of segments, second subsequence of segments, third subsequence of segments and fourth subsequence of segments each cover a fourth of a distance between the opposing suspension zones.

9. The planar micromechanical actuator according to claim 8 , wherein a joint, joining the second segment and third segment is configured to move along the second direction upon an actuation of the planar micromechanical actuator.

10. The planar micromechanical actuator according to claim 8 , wherein each subsequence of segments comprises an identical number of segments.

11. The planar micromechanical actuator according to claim 8 , wherein the planar micromechanical actuator comprises a neutral axis formed in the second electrode between the opposing suspension zones.

12. The planar micromechanical actuator according to claim 8 , wherein each subsequence forming the sequence of segments comprises exactly one segment.

13. A planar micromechanical actuator according to claim 8 , wherein the first and second electrode are affixed to each other by first spacers and the second and third electrode are affixed to each other by second spacers.

14. The planar micromechanical actuator according to claim 8 , wherein the first electrode comprises a greater thickness than the third electrode in the first and fourth subsequence of the sequence of segments and wherein the first electrode comprises a smaller thickness than the third electrode in the second and third subsequence of the sequence of segments.

15. The planar micromechanical actuator according to claim 14 , wherein the first and second electrode are affixed to each other by first spacers and the second and third electrode are affixed to each other by second spacers,
wherein the first and second spacers and the second electrode at the first and second spacers are formed such that an overall thickness of the planar micromechanical actuator remains constant on borders between the subsequences of segments.

16. The planar micromechanical actuator according to claim 15 , wherein gaps formed between the first and second electrode and the first spacers are arc shaped, and
wherein gaps formed between the second and third electrode and the second spacers are arc shaped.

17. The planar micromechanical actuator according to claim 13 , wherein the spacers are formed, at least partially, from an insulating material.

18. The planar micromechanical actuator according to claim 8 , wherein in each segment of the first and fourth subsequences, an outer surface of the first electrode comprises a first curvature forming a protrusion of the planar micromechanical actuator in the respective segment, and wherein an outer surface of the third electrode directed oppositely to the outer surface of the first electrode comprises a second curvature forming a recess of the planar micromechanical actuator wherein the first curvature comprises a smaller radius than the second curvature.

19. The planar micromechanical actuator according to claim 8 , wherein in each segment of the second and third subsequences, an outer surface of the first electrode comprises a first curvature forming a recess of the planar micromechanical actuator in the respective segment, and wherein an outer surface of the third electrode directed oppositely to the outer surface of the first electrode comprises a second curvature forming a protrusion of the micromechanical actuator wherein the first curvature comprises a greater radius than the second curvature.

20. A micromechanical actuator arrangement comprising a stack of planar micromechanical actuators comprising
a first planar micromechanical actuator comprising a first plana

Assignees

• Fraunhofer Ges Forschung

Inventors

• Conrad Holger
• Gaudet Matthieu
• Schenk Harald
• Uhlig Sebastian

Classifications

• B81B2201/038

  Microengines and actuators not provided for in B81B2201/031 - B81B2201/037 · CPC title

• B81B7/0003

  MEMS mechanisms for assembling automatically hinged components, self-assembly devices (self-assembly processes B81C1/00007) · CPC title

• F04B43/046

  with piezoelectric drive · CPC title

• F04B1/063

  by using a valve in a system with several pumping chambers wherein the flow-path through the chambers can be changed, e.g. between series and parallel flow · CPC title

• B81B2203/0127

  Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function · CPC title