Vibrating gyroscope

• US 6,281,618 B1
• Filed: 04/17/2000
• Issued: 08/28/2001
• Est. Priority Date: 04/22/1999
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Fujimoto, Katsumi, Ishitoko, Nobuyuki
• Primary Examiner(s): Budd, Mark O.
• Application Number:
  US09/550,872
• Time in Patent Office: 498 Days
• Field of Search: 310/321, 310/323.01, 310/329, 310/316.01, 310/330, 310/331, 310/332, 310/366, 735/051.2, 735/051.4, 735/051.5, 735/051.6
• US Class Current: 310/329
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis

Abstract

A vibrating gyroscope includes two planar vibrating plates arranged to oppose each other. The two vibrating plates vibrate under buckling vibration mode and a second-order bending vibration mode which is degenerated with or close to the buckling vibration mode. The vibrating gyroscope detects Coriolis force by detecting displacements in amplitude balance of the second-order bending vibration modes generated when an angular rotation velocity around an axis parallel to surfaces of the vibrating plates is applied.

Claims

1. A vibrating gyroscope comprising two planar vibrating plates arranged to oppose each other, wherein the two vibrating plates vibrate under buckling vibration mode and a second-order bending vibration mode which is degenerated with or close to the buckling vibration mode, and the vibrating gyroscope detects Coriolis force by detecting displacements in amplitude balance of the second-order bending vibration modes generated when an angular rotation velocity around an axis parallel to surfaces of the vibrating plates is applied.

2. The vibrating gyroscope according to claim 1, comprising:

an intermediate member formed between the two vibrating plates to form a spaced section between the two vibrating plates, and

a plurality of exciting and detecting elements formed on the vibrating plates to vibrate the vibrating plates and to output signals generated by vibrations of the vibrating plates,

wherein a first detecting section comprises a combination of two adjacent exciting and detecting elements, a second detecting section comprises another combination of two different adjacent exciting and detecting elements, and the first detecting section and the second detecting section are arranged perpendicular to each other.

3. The vibrating gyroscope according to claim 2, wherein the exciting and detecting elements are formed in positions opposing the spaced section, but not opposing the intermediate member.

4. The vibrating gyroscope according to claim 2, wherein the individual exciting and detecting elements comprises piezoelectric substrates having electrodes sectioned crosswise thereon.

5. The vibrating gyroscope according to claim 2, wherein each of the individual exciting and detecting elements comprises piezoelectric substrate having four electrodes thereon.

6. The vibrating gyroscope according to claim 2, wherein each vibrating plate is formed of a metal plate, and the exciting and detecting elements comprise piezoelectric elements sectioned crosswise into four formed on each metal plate.

7. The vibrating gyroscope according to claim 2, wherein the intermediate member is formed of a frame member having a through-opening in its central portion.

8. The vibrating gyroscope according to claim 2, wherein the intermediate member is formed of multiple members arranged on multiple end portions of the vibrating plates.

9. The vibrating gyroscope according to claim 7, wherein the individual exciting and detecting elements are formed in positions opposing the through-opening.

10. The vibrating gyroscope according to claim 2, further including a circuit for applying an oscillation signal to the exciting and detecting elements to vibrate the vibrating plates and a circuit for detecting detection signals from the first and second detecting sections.