Stepping actuator and method of manufacture therefore

• US 7,265,477 B2
• Filed: 01/03/2005
• Issued: 09/04/2007
• Est. Priority Date: 01/05/2004
• Status: Expired due to Fees

• Current Assignee: Chang-Feng Wan
• Original Assignee: Chang-Feng Wan
• Inventors: Wan, Chang-Feng
• Primary Examiner(s): Mullins; Burton
• Application Number:
  US11/028,409
• Publication Number:
  US 20050146241A1
• Time in Patent Office: 974 Days
• Field of Search: 310/309, 200/181, 257/600
• US Class Current: 310/309
• CPC Class Codes: H01G 5/16 using variation of distance between electrodes
• CPC Class Codes: H01G 5/38 Multiple capacitors, e.g. ganged
• CPC Class Codes: H02N 1/006 of the gap-closing type H02N1/004 takes precedence

Abstract

An embodiment of the present invention provides a stepping actuator, comprising a suspended membrane comprising a plurality of movable electrodes connected by plurality of spring hinges to a payload platform; and anchors connecting said membrane to a substrate, said substrate comprising a plurality of fixed electrodes; wherein said movable electrodes of said suspended membrane and said fixed electrodes from said substrate form parallel-plate electrostatic sub-actuators.

Claims

1. A stepping actuator, comprising:

a suspended planar membrane comprising a plurality of movable electrodes, spring hinges, and anchors, and a payload platform, wherein said movable electrode and said payload platform are connected in a series by said spring hinges; and

a plurality of anchors connecting said membrane to a substrate, said substrate comprises a plurality of fixed electrodes;

wherein said movable electrodes and said fixed electrodes form parallel-plate electrostatic sub-actuators, said parallel-plate electrostatic sub-actuators have graduated air gaps, and said fixed electrodes comprise at least one insulator island.

2. The stepping actuator of claim 1, wherein said insulator island forms at least one set of stairs.

3. The stepping actuator in claim 1, wherein substantially all of said fixed electrodes are electrically connected to each other.

4. The stepping actuator device in claim 1, wherein said fixed electrodes are formed on the steps of a stair-shaped insulator.

5. The stepping actuator device in claim 1 comprises two sets of said electrostatic sub-actuators, wherein said electrostatic sub-actuators are evenly distributed on the opposite sides of said payload platform and are symmetric with respect to a vertical medial plane of said payload platform.

6. A multilevel actuator comprising a plurality of the stepping actuators in claim 1 that are vertically stacked, wherein said payload platform of a lower-level said stepping actuator comprises the substrate of a upper-level said stepping actuator.

7. The stepping actuator of claim 1, wherein said payload platform comprises a mirror.

8. The stepping actuator of claim 1, wherein said stepping actuator is a varactor and wherein said payload platform comprises one electrode plate of said capacitor and said substrate comprises the other electrode plate of said capacitor.

9. The stepping actuator of claim 1, wherein said payload platform comprises at least one focusing lens.

10. The stepping actuator of claim 1, wherein one side of said payload platform hinges on said parallel-plate electrostatic sub-actuators and the opposite side of said payload platform hinges on an anchor.

11. The stepping actuator of claim 1, wherein said fixed electrode comprises insulator bumps in a reticulate metal matrix layer;

said insulator bumps are taller than and underlap said reticulate metal matrix layer.

12. The stepping actuator of claim 1, wherein said payload platform comprises an electrode, said substrate comprises another electrode, thereby said stepping actuator device forms a contact switch or a capacitive switch.

13. The stepping actuator of claim 1, wherein said movable electrodes and said fixed electrodes are configured such that said electrostatic sub-actuators move in the lateral direction.