Patent ID: 7140251
Filing Date: 2006-11-28
Classification: G01C

Abstract:
1. A device for measuring a physical value using a vibrator: said device comprising; a vibrator comprising at least one bending vibration arm for driving and at least one bending vibration arm for detection, both vibrating along a specified plane in bending mode; a driving electrode for exciting a driving vibration in said vibrator; a detecting electrode for obtaining an output signal based on a detection vibration excited in said vibrator in response to said physical value; and a detection circuit for processing said output signal to provide a detection signal corresponding with said physical value, wherein each of said bending vibration arms comprises at least a pair of base parts and a connecting part connecting said base parts, and said connecting and base parts define a pair of recesses, wherein said driving electrode is provided on and said detecting electrode is not provided on said bending vibration arm for driving and said detecting electrode is provided on and said driving electrode is not provided on said bending vibration arm for detection, wherein a ratio “a/b” of the thickness “a” of said connecting part to the thickness “b” of said base part is 0.05 or larger and 0.4 or smaller and a ratio “d/c” of the width “d” of said recess to the width “c” of said bending vibration arm is 0.4 or larger and 0.95 or smaller; and wherein each of said bending vibration arm for driving and said bending vibration arm for detection comprises a pair of first planes substantially perpendicular to said specified plane and a pair of second planes substantially parallel with said specified plane, and wherein said recesses are provided on the sides of said second planes, respectively.