Inertial micromechanical tuning-fork gyrometer

• US 20050081630A1
• Filed: 10/07/2004
• Published: 04/21/2005
• Est. Priority Date: 10/10/2003
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: Rougeot, Claude, Leverrier, Bertrand, Inglese, Jerome
• Granted Patent: US 7,267,004 B2
• Time in Patent Office: Days
• US Class Current: 73/504.120
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: G01C 19/5769 Manufacturing; Mounting; Housings

Abstract

The invention relates to a micromachined gyrometer having a planar moving structure anchored on a fixed substrate by anchoring feet, the fixed substrate being mounted on a support substrate via fastening means, the moving structure comprising at least two moving assemblies that are symmetrical with respect to an axis of symmetry A1; the anchoring feet are located outside this axis A1. The fixed substrate has etched features for the purpose of partly isolating at least one region from the rest of the fixed substrate, this region having a portion of the fixed substrate that includes at least one anchoring foot, and the fixed substrate is mounted on the support substrate via fastening means applied outside the region.

Claims

1. A micromachined, gyrometer comprising:

planar moving structure anchored on a fixed substrate by anchoring feet, the fixed substrate being mounted on a support substrate by fastening means, the moving structure comprising at least two moving assemblies that are symmetrical with respect to an axis of symmetry A1 contained in this plane and are coupled by a coupling structure that connects these two assemblies in order to allow transfer of mechanical vibration energy between them, the anchoring feet being located outside this axis of symmetry A1, wherein the fixed substrate has etched features for partly isolating at least one region from the rest of the fixed substrate, this region having a portion of the fixed substrate that includes at least one anchoring foot, and wherein the fixed substrate is mounted on the support substrate by fastening means applied outside the at least one region.

2. The gyrometer as claimed in claim 1, wherein the region furthermore includes a portion of the fixed substrate, lying along the axis A1, this portion being connected to the portion having at least one anchoring foot.

3. The gyrometer as claimed in claim 2, wherein the portion having at least one anchoring foot comprises at least two arms located on either side of the portion lying along the axis A1.

4. The gyrometer as claimed in claim 1, wherein the fastening means are applied to the edges of the fixed substrate.

5. The gyrometer as claimed in claim 1, wherein each moving assembly comprises two moving masses that are attached to flexure arms, a structure for exciting the vibration of each mass in the plane of the structure, and a structure for detecting a vibration of the masses transversely to the plane.

6. The gyrometer as claimed in claim 5, wherein the flexure arms connected to a moving mass are also connected to at least one anchoring foot, the structure for coupling between masses being connected directly to the moving masses independently of the flexure arms, this structure comprising at least two longitudinal links extending on either side of the sensitive axis, parallel to the latter, between the moving masses, at least one transverse link connecting the two longitudinal links, and at least two transverse arms connecting each moving mass to a respective longitudinal link, the latter two transverse arms being located on either side of the moving mass and being connected to the moving mass.

7. The gyrometer as claimed in claim 2, wherein the fastening means are applied to the edges of the fixed substrate.

8. The gyrometer as claimed in claim 3, wherein the fastening means are applied to the edges of the fixed substrate.

9. The gyrometer as claimed in claim 2, wherein each moving assembly comprises two moving masses that are attached to flexure arms, a structure for exciting the vibration of each mass in the plane of the structure, and a structure for detecting a vibration of the masses transversely to the plane.

10. The gyrometer as claimed in claim 3, wherein each moving assembly comprises two moving masses that are attached to flexure arms, a structure for exciting the vibration of each mass in the plane of the structure, and a structure for detecting a vibration of the masses transversely to the plane.

11. The gyrometer as claimed in claim 4, wherein each moving assembly comprises two moving masses that are attached to flexure arms, a structure for exciting the vibration of each mass in the plane of the structure, and a structure for detecting a vibration of the masses transversely to the plane.