Angular velocity detecting device

• US 8,616,058 B2
• Filed: 11/14/2012
• Issued: 12/31/2013
• Est. Priority Date: 06/22/2007
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Jeong, Heewon, Goto, Yasushi
• Primary Examiner(s): Larkin, Daniel S
• Assistant Examiner(s): Shah, Samir M
• Application Number:
  US13/677,038
• Publication Number:
  US 20130152682A1
• Time in Patent Office: 412 Days
• Field of Search: 735/040.1, 735/040.2, 735/040.3, 735/040.4, 735/041.2, 735/140.1, 735/140.2, 735/143.8, 735/041.4
• US Class Current: 73/504.14
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames
• CPC Class Codes: G01C 19/5762 the sensing mass being connected to a driving mass, e.g. driving frames
• CPC Class Codes: G01P 3/22 transferred to the indicator by electric or magnetic means

Abstract

A high-performance angular rate detecting device is provided. A driving part including a drive frame and a Coriolis frame is levitated by at least two fixing beams which share a fixed end and are extending in a direction orthogonal to a driving direction, thereby vibrating the driving part. Even when a substrate is deformed by mounting or heat fluctuation, internal stress generated to the fixed beam and a supporting beam is small, thereby maintaining a vibrating state such as resonance frequency and vibration amplitude constant. Therefore, a high-performance angular rate detecting device which is robust to changes in mounting environment can be obtained.

Claims

1. An angular rate detecting device comprising:

a substrate;

a fixed part formed above the substrate;

a drive frame suspended from the fixed part; and

a Coriolis frame suspended from the fixed part via the drive frame,

wherein the drive frame is suspended from the fixed part by first to sixth beams,

wherein one end of the first beam and one end of the fourth beam are connected to the fixed part;

wherein the first and fourth beams are extended in a direction perpendicular to a drive direction,

wherein one end of the third beam and one end of the sixth beam are connected to the drive frame,

wherein the third and the sixth beams are extended in the direction perpendicular to the drive direction,

wherein the second beam is connected to another end of the first beam and another end of the third beam and is extended in the drive direction,

wherein the fifth beam is connected to another end of the fourth beam and another end of the sixth beam and is extended in the drive direction, and

wherein the first to third beams and the fourth to sixth beams are provided symmetrically with respect to an axis extended in the drive direction and through the fixed part.

2. The angular rate detecting device according to claim 1,

wherein the drive frame is provided inside the Coriolis frame on a surface of an active layer where the drive frame and the Coriolis frame are formed.

3. The angular rate detecting device according to claim 1,

wherein at least two sets of the first to sixth beams are provided with predetermined spacing therebetween in the drive direction.

4. An angular rate detecting apparatus having the angular rate detecting device according to claim 1 as one unit of a sensor unit, and at least two such sensor units are provided and coupled by a linking beam, so that the sensor units are interlocked.

5. The angular rate detecting device according to claim 1,

wherein a plan shape of the drive frame is a rectangular shape, and

wherein the first to sixth beams are provided inside the rectangular shape.

6. The angular rate detecting device according to claim 1,

wherein a plan shape of the Coriolis frame is a rectangular shape, and

wherein the drive frame is provided inside the rectangular shape of the Coriolis frame.

7. The angular rate detecting device according to claim 1,

wherein the second beam is of smaller length than the first beam,

wherein the second beam is of larger width than the first beam,

wherein the fifth beam is of smaller length than the fourth beam, and

wherein the fifth beam is of larger width than the fourth beam.