Patent ID: 8621927

Claim:
An angular rate sensor comprising: a planar substrate; first and second generally planar masses disposed above the substrate and spaced apart along a pre-selected drive axis in the plane of the masses; an input axis perpendicular to the plane of the masses; a sense axis in the plane of the masses and perpendicular to the drive axis; first and second driving frames disposed along the drive axis in a region between the masses; coupling means for constraining the driving frames for anti-phase movement along the drive axis; flexures connecting the first and second masses to the first and second driving frames respectively, wherein said flexures substantially constrain the masses to move together with respective driving frames along the drive axis in drive-mode, and permit the masses to move relatively to the driving frames in directions parallel to the sense axis in sense-mode; actuation means for exciting the driving frames to oscillate along the drive axis in drive-mode; detection means responsive to the anti-phase movement of the masses in directions parallel to the sense axis for monitoring rate of rotation about the input axis; wherein said coupling means includes a pair of anti-phase couplers disposed in a region between the drive frames and spaced apart along the sense axis, each said anti-phase coupler comprising: a supporting beam which extends in a direction substantially parallel to the drive axis and is mounted to the substrate at its two ends; first and second link springs which extend from the first and second driving frames respectively to the supporting beam and join one another to form a common joint at substantially the midpoint of the supporting beam.