Oscillating mass resonator

• US 7,637,155 B2
• Filed: 10/05/2005
• Issued: 12/29/2009
• Est. Priority Date: 10/06/2004
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Delevoye, Elisabeth
• Primary Examiner(s): Kwok; Helen C.
• Application Number:
  US11/576,777
• Publication Number:
  US 20090249873A1
• Time in Patent Office: 1,546 Days
• Field of Search: 735/040.4, 735/041.2, 735/041.4, 735/041.5, 735/041.6, 735/143.2, 735/143.6, 735/143.8
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: H03H 2009/02354 applied along the periphery, e.g. at nodal points of the ring
• CPC Class Codes: H03H 2009/02503 Breath-like, e.g. Lam? mode, wine-glass mode
• CPC Class Codes: H03H 2009/2442 Square resonators
• CPC Class Codes: H03H 9/02275 Comb electrodes
• CPC Class Codes: H03H 9/02338 Suspension means
• CPC Class Codes: H03H 9/2405 of microelectro-mechanical resonators
• CPC Class Codes: H03H 9/2431 Ring resonators

Abstract

Suspension and coupling beams of oscillating masses in a device which serves, for example, as a gyro and that includes oscillating masses form a single continuous network that allows the device to have a compact design. Preferably, a junction beam surrounds the two masses.

Claims

1. A resonator comprising:

a substrate;

at least two oscillating masses;

means for making the masses oscillate using electrical forces, suspension beams for suspending the masses from the substrate, and coupling beams that link the masses together, wherein the suspension beams are all connected to the masses through the coupling beams, with the suspension beams and the coupling beams forming a continuous single assembly of beams that includes attachment beams to the substrate and attachment beams to the masses,

wherein the continuous single assembly of beams also includes a junction beam that undergoes deformation according to oscillation of the masses, extending along a closed line to which the attachment beams to the substrate and the attachment beams to the masses are connected.

2. A resonator according to claim 1, wherein the junction beam extends over a curved line.

3. A resonator according to claim 1, wherein the junction beam surrounds the masses, which are in a form of half-moons that have rectilinear sides opposite each other and curved sides opposite the junction beam.

4. A resonator according to claim 1, wherein the attachment beams to the substrate include anchorage beams that extend overall in a direction of alignment of the masses between two regions of attachment to the substrate, which are perpendicular to the anchorage beams and joined to the anchorage beams at mid-distance from the regions of attachment.

5. A resonator according to claim 3, wherein the junction beam surrounds the masses, and the means for making the masses oscillate includes elements for producing oscillation located between the junction beam and the masses.

6. A resonator according to claim 1, wherein the substrate includes a decoupling frame that surrounds the masses, the means for making the masses oscillate, and the suspension beams and the coupling beams, and said decoupling frame being fixed to an underlying portion of the substrate by two frame anchorage regions aligned in a principal direction of oscillation of the masses.

7. A resonator according to claim 6, wherein the attachment beams to the masses are aligned with the frame anchorage regions.

8. A resonator according to claim 7, wherein the frame and the junction beam are configured to form end-stops in front of the frame anchorage regions and the oscillating masses possess opposite sides configured to form a mutual end stop.

9. A resonator according to claim 5, wherein the masses extend between the means for making the masses oscillate and possess opposite sides between said masses equipped with interlocking electric combs.

10. A resonator according to claim 1, wherein the masses each include two-sub-masses placed symmetrically along a principle direction of oscillation of the masses, and the coupling beams include, for each mass, a sub-assembly of beams that extends between the sub-masses and that include two beams respectively linked to the sub-masses and to an interconnecting beam with the two beams connected to the sub-masses extending along a principal direction of oscillation of the masses.

11. A resonator according to claim 1, further comprising electrodes for measuring capacitance with the masses, the electrodes being fixed to the substrate and arranged in mass housings and being asymmetric along a direction of oscillation of the masses.

12. A resonator according to claim 1, wherein the means for making the masses oscillate includes interlocking toothed combs that exhibit an overlap length that is greater than an oscillation amplitude of the oscillating masses.

13. A resonator according to claim 9, wherein the interlocking electrical combs have teeth with a total mass equal to a total mass of extensions present on a face opposite the teeth of each oscillating mass.