Angular velocity sensor

• US 20080210007A1
• Filed: 01/23/2008
• Published: 09/04/2008
• Est. Priority Date: 01/23/2007
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited, Fujitsu Media Devices Limited (Fujitsu Limited)
• Original Assignee: Fujitsu Limited, Fujitsu Media Devices Limited (Fujitsu Limited)
• Inventors: Takahashi, Yuji, Inoue, Hiroaki, Katsuki, Takashi, Ishikawa, Hiroshi, Nakazawa, Fumihiko, Yamaji, Takayuki
• Application Number:
  US12/010,249
• Publication Number:
  US 20080210007A1
• Time in Patent Office: Days
• US Class Current: 73/504.16
• CPC Class Codes: G01C 19/5628 Manufacturing; Trimming; Mounting; Housings
• CPC Class Codes: G01C 19/5712 the devices involving a micromechanical structure

Abstract

An angular velocity sensor includes: a first tuning-fork vibrator having a first base and first aims extending from the first base in a first direction; a second tuning-fork vibrator having a second bass and second arms extending from the second base in a second direction; and a double gimbal portion mat has a drive gimbal portion vibrating about an axis extending in a fourth direction, and a sense gimbal portion vibrating about an axis extending in a fifth direction and senses an angular velocity about an axis extending in a third direction.

Claims

1. An angular velocity sensor comprising:

a first tuning-fork vibrator having a first base and first arms extending from the first base in a first direction;

a second tuning-fork vibrator having a second base and second arms extending from the second base in a second direction; and

a double gimbal portion that has a drive gimbal portion vibrating about an axis extending in a fourth direction, and a sense gimbal portion vibrating about an axis extending in a fifth direction and senses an angular velocity about an axis extending in a third direction.

2. The angular velocity sensor according to claim 1, wherein the first, second and third directions are mutually orthogonal to each other.

3. The angular velocity sensor according to claim 1, wherein the fourth and fifth directions are orthogonal to each other.

4. The angular velocity sensor according to claim 1, wherein the first and second tuning-fork vibrators are provided so that at least parts of the first and second tuning-fork vibrators overlap with each other in a direction horizontal to a plane that includes the first and second directions.

5. The angular velocity sensor according to claim 1, wherein the double gimbal portion is provided in the third direction with respect to the first and second tuning-fork vibrators.

6. The angular velocity sensor according to claim 1, wherein the double gimbal portion, the first tuning-fork vibrator and the second tuning-fork vibrator are provided so that at least parts of the double gimbal portion, the first tuning-fork vibrator and the second tuning-fork vibrator overlap with each other in a direction horizontal to a plane that includes the first and second directions.

7. The angular velocity sensor according to claim 1, wherein the first and second tuning-fork vibrators are arranged so as to form an L shape, and the double gimbal portion is arranged along sides of the first and second tuning-fork vibrators.

8. The angular velocity sensor according to claim 1, further comprising first torsion bars provided on opposite sides of the sense gimbal portion in order to support the sense gimbal portion, wherein a maximum width connecting the opposite sides of the sense gimbal portion is greater than a width connecting opposite side portions of the sense gimbal portion to which the first torsion bars are fixed.

9. The angular velocity sensor according to claim 1, further comprising second torsion bars provided on opposite sides of the drive gimbal portion in order to support the drive gimbal portion, wherein a maximum width connecting the opposite sides of the drive gimbal portion is greater than a width connecting opposite side portions of the drive gimbal portion to which the second torsion bars are fixed.