Coupled micromachined structure

• US 6,981,414 B2
• Filed: 04/01/2004
• Issued: 01/03/2006
• Est. Priority Date: 06/19/2001
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Weber, Mark W., Knowles, Gary R.
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US10/816,719
• Publication Number:
  US 20040255672A1
• Time in Patent Office: 642 Days
• Field of Search: 735/041.2, 735/040.4, 735/142.4, 735/041.4, 735/161.6, 735/142.9, 735/143.2, 736/51
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01P 2015/0814 for translational movement of the mass, e.g. shuttle type

Abstract

A suspended, coupled micromachined structure including two proof masses and multiple support arms configured to suspend the masses above a substrate and a coupling spring element having two ends. Each end of the coupling spring element may be attached to a proof mass at a point between the proof masses. The frequency response characteristics of the proof masses may be improved.

Claims

1. A micromachined device comprising:

a first proof mass;

a second proof mass;

a plurality of support arms attached to the first proof mass and second proof mass, each of the support arms flexibly coupling the proof masses to a substrate;

wherein at least one of the support arms includes a first end coupled to the substrate and a second end coupled to the substrate, the at least one support arm comprising;

a first spring element attached to the substrate;

a second spring element attached to the substrate; and

a rigid lateral element having a first end and a second end, the first end of the rigid lateral element connected to the first spring element and the second end of the rigid lateral element connected to the second spring element;

wherein a proof mass is connected to the rigid lateral element at a point between the first end and the second end of the support arm and wherein the support arm is substantially diametrical about the point, in a plane that is parallel to the substrate; and

at least one coupling spring having a first end and a second end, the first end of the at least one coupling spring connected to the first proof mass and the second end of the at least one coupling spring connected to the second proof mass.

2. The micromachined device of claim 1, wherein the first end of the at least one coupling spring is connected to a side of the first proof mass that is closest to the second proof mass and the second end of the at least one coupling spring is connected to a side of the second proof mass that is closest to the first proof mass.

3. The micromachined device of claim 1, wherein the first end of the at least one coupling spring is connected to a side of the first proof mass that is closest to the second proof mass at substantially the midpoint of the side of the first proof mass and the second end of the at least one coupling spring is connected to a side of the second proof mass that is closest to the first proof mass at substantially the midpoint of the side of the second proof mass.

4. The micromachined device of claim 3, wherein the first end of the at least one coupling spring and the second end of the at least one coupling spring lie on a straight line that comprises an axis of oscillation of the first proof mass and the second proof mass.

5. The micromachined device of claim 1, wherein the point is substantially equidistant from the ends of the rigid lateral element.

6. The micromachined device of claim 1, wherein the connection of the first spring element to the rigid lateral element creates a first end flexure point, the connection of the second spring element to the rigid lateral element creates a second end flexure point, and the connection of a proof mass to the rigid lateral element creates a middle flexure point.

7. The micromachined device of claim 1, wherein the first end flexure point, the second end flexure point, and the middle flexure point lie on a substantially straight line.

8. The micromachined device of claim 7, wherein the substantially straight line comprises an axis of alignment.

9. The micromachined device of claim 8, wherein the axis of alignment is parallel to an axis of oscillation of the proof mass.

10. The micromachined device of claim 9, wherein when at least one of the proof masses moves along the axis of oscillation, the middle flexure point where it is coupled to a rigid lateral element moves along the axis of alignment.

11. The micromachined device of claim 10, further including a second support arm having a first end coupled to the substrate and a second end coupled to the substrate, wherein at least one of the proof masses is connected to the second support arm at a point between the first end and the second end of the rigid lateral element.

12. The micromachined device of claim 11, wherein the at least one support arm and the second support arm are positioned on the same side of at least one of the proof masses.

13. The micromachined device of claim 11, wherein the at least one support arm and the second support arm are positioned on opposite sides of at least one of the proof masses.