US Patent 7255005 Piezoelectric vibrating gyro element and gyro sensor

A piezoelectric vibrating gyro element is constructed by crystal and includes at least in the same plane a base portion; a pair of vibrating arms for detection extended out from the base portion to both sides in a straight line shape, and having groove portions; a weight portion connected to the tip of each of the vibrating arms for detection; a pair of connecting arms extended out from the base portion to both the sides in directions perpendicular to the vibrating arms for detection; pairs of vibrating arms for driving each extended out from the tip portion of each of the connecting arms to both the sides perpendicularly to this tip portion, and having groove portions; and a weight portion connected to the tip of each of the vibrating arms for driving; wherein, when the vibrating arm for driving is set to Ld in length and Wd in width, and the vibrating arm for detection is set to Lp in length and Wp in width, and the connecting arm is set to Lc in length and Wc in width, the piezoelectric vibrating gyro element is constructed so as to form the following formulas100≦Wd/Ld2≦580,135≦Wp/Lp2≦800 and65≦Wc/Lc2≦390.