Z-axis vibration gyroscope

• US 20040083812A1
• Filed: 11/04/2002
• Published: 05/06/2004
• Est. Priority Date: 11/04/2002
• Status: Active Grant

• Current Assignee: Micro-Optimus Technologies, Inc. (Quarterhill Inc. (f/k/a Wi-LAN Inc.))
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ichinose, Toshihiko
• Granted Patent: US 6,823,733 B2
• Time in Patent Office: Days
• US Class Current: 73/504.02
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis

Abstract

An angular velocity sensor is disclosed having a sensing element and a pair of driven mass drive elements. The driven mass drive elements have a support structure which defines at least one vibrational node. the driven mass drive element drive elements are coupled to the sensing element at the node so as to allow the driven mass drive elements to oscillate about an axis to generate Coriolis forces, which are measured by the sensing element.

Claims

1. An angular velocity sensor comprising:

a sensing element;

a pair of drive elements defining at least one vibrational node, each of the drive elements being coupled to the sensing element at its respective vibrational node; and

wherein the drive element oscillates about an axis and comprises an inertial mass configured to generate Coriolis forces which are measured by the sensor, and wherein the sensor is vibrationally decoupled from the sensing element.

2. The angular velocity sensor according to claim 1 comprising:

a single support member coupled to the sensing element and disposed between the pair of drive elements.

3. The angular velocity sensor according to claim 1 wherein the drive elements define a plurality of first charge bearing plates and wherein said first charge bearing plates interleave with a plurality of second charge bearing plates disposed on a drive comb.

4. The angular velocity sensor according to claim 3 wherein the drive elements have a vibrational resonant frequency and the first and second charge bearing plates are configured to accept an alternating charge, said alternating charge having a frequency of about a vibrational resonant frequency of the drive elements.

5. The angular velocity sensor according to claim 1 wherein the sensing element has a plurality of third charge bearing plates and wherein said third charge bearing plates interleave with a plurality of fourth charge bearing plates disposed on a sensing comb.

6. The angular velocity sensor according to claim 5 further comprising a support frame, said support frame being disposed between said sensing element and said drive element;

and

wherein said support frame defines a portion of said sensing element.

7. An angular velocity sensor comprising:

a sensing element;

a pair of driven mass drive elements, said driven mass drive elements having a support structure which defines at least one vibrational node;

wherein the driven mass drive elements are coupled to the sensing element at the vibrational node so as to allow the driven mass drive elements to oscillate about an axis to generate Coriolis forces which are measured by the sensing element.

8. The angular velocity sensor according to claim 7 wherein said support structure defines a tuning fork.

9. The angular velocity sensor according to claim 7 wherein said support structure defines a double tuning fork.

10. An angular velocity sensor comprising:

a support frame;

a plurality of drive elements each having a support element defining at least one vibrational node, the drive elements being coupled to the support frame at the vibrational node;

a sensing element coupled to the support frame; and

wherein the drive elements oscillate about an axis and comprises an inertial mass configured to generate Coriolis forces.

11. The angular velocity sensor according to claim 10 comprising:

a pair of drive elements coupled to the support frame; and

a single support member coupled to the support frame and the drive element.

12. The angular velocity sensor according to claim 10 wherein said support structure defines a tuning fork.

13. The angular velocity sensor according to claim 10 wherein said support structure defines a double tuning fork.

14. The angular velocity sensor according to claim 10 wherein the drive element defines a plurality of first charge bearing plates and wherein said first charge bearing plates interleave with a plurality of second charge bearing plates disposed on a drive comb.

15. The angular velocity sensor according to claim 10 wherein the drive elements have a vibrational resonant frequency and the first and second charge bearing plates are configured to accept an alternating charge, said alternating charge having a frequency of about the vibrational resonant frequency.

16. The angular velocity sensor according to claim 10 wherein the sensing element has a plurality of third charge bearing plates and wherein said third charge bearing plates interleave with a plurality of fourth charge bearing plates disposed on a sensing comb.

17. An angular velocity sensor comprising:

a pair of drive elements each having a support element defining at least one vibrational node, the drive elements being coupled to the support frame at the vibrational node;

a sensing element coupled to the drive elements;

a single support member coupled to the sensing and drive elements; and

wherein the drive elements oscillate about an axis and comprises an inertial mass configured to generate Coriolis forces.

18. An angular velocity sensor comprising:

a means for generating Coriolis forces;

a means for sensing Coriolis forces;

a means for coupling said means for generating Coriolis forces and said means for sensing Coriolis forces, said means for coupling having a vibrational node, the vibrational node being disposed between said means for generating Coriolis forces and said means for sensing Coriolis forces.

19. The angular velocity sensor according to claim 18 further having a single support pole configured to support the means for generating Coriolis forces.