Inertial sensor

• US 8,096,181 B2
• Filed: 06/06/2007
• Issued: 01/17/2012
• Est. Priority Date: 06/16/2006
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Fukumoto, Koji
• Primary Examiner(s): Williams, Hezron E
• Assistant Examiner(s): Shabman, Mark A
• Application Number:
  US12/303,902
• Publication Number:
  US 20100223996A1
• Time in Patent Office: 1,686 Days
• Field of Search: 735/041.2
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 2015/084 the mass being suspended at more than one of its sides, e.g. membrane-type suspension, so as to permit multi-axis movement of the mass

Abstract

An inertial sensor includes a drive structure 11 which performs one reference oscillation in an XY plane, and force detecting structures 12 (12-1 to 12-4) which each have a plurality of detection axes and which are arranged on an X axis and a Y axis in the drive structure 11 in pairs at positions symmetrical about an origin, wherein angular velocities in three axes and accelerations in three axes are detected by providing the force detecting structure 12 with the plurality of detection axes including at least one detection axis orthogonal to the one reference oscillation.

Claims

1. An inertial sensor comprising:

a drive structure operative to perform one reference oscillation in an XY plane, the XY plane being defined by an X axis and a Y axis; and

force detecting structures arranged on the X axis and the Y axis in pairs and at positions symmetrical about an origin of the XY plane, each of said force detecting structures including (a) elastic supports, (b) an oscillator on one side of the elastic supports, and (c) piezo elements on an opposite side of the elastic supports,

wherein,

a Z axis is orthogonal to both the X axis and the Y axis,

each of said oscillators is supported in a manner of being suspended from the respective elastic supports such that each oscillator is provided with degrees of freedom in directions parallel to the X axis, the Y axis, and the Z axis, and in rotating directions about each of the X, Y, and Z axes, and

said inertial sensor is effective to detect angular velocities along three axes and accelerations along three axes in accordance with said one reference oscillation.

2. The inertial sensor as set forth in claim 1, wherein

when said force detecting structures on said X axis oscillate in the sense of moving away from said origin, said force detecting structures on said Y axis oscillate in the sense of approaching said origin;

and

when said force detecting structures on said X axis oscillate in the sense of approaching from said origin, said force detecting structures on said Y axis oscillate in the sense of moving away from said origin.

3. The inertial sensor as set forth in claim 1, wherein said drive structure performs simple harmonic oscillation in rotating directions about said origin of said X axis and said Y axis.

4. The inertial sensor as set forth in claim 1, wherein the driving system of said force detecting structures is electrostatic driving, piezoelectric driving or electromagnetic driving.

5. The inertial sensor as set forth in claim 1, wherein the force detection by said force detecting structures is electrostatic detection, piezoelectric detection, piezo detection or electromagnetic detection.