| 摘要 |
PROBLEM TO BE SOLVED: To improve detecting sensitivity by flattening a center of a lower end face of a tuning fork groove, thereby suppressing a sensor output (normal output) in the case of no rotation. SOLUTION: A tuning fork type crystal sensor of an angular velocity sensor is formed, for example, by providing driving electrodes 7a, 7b, 8a, 8b for exciting a tuning fork vibration and sensor electrodes 9a, 9b, 10a, 10b for detecting charge generated by Coriolis force at a tuning fork-like crystal 6 formed by rotting a Z-cut plate having a main surface crossing perpendicularly to the Z-axis of a crystal axis at about 0 to 5 degrees at the X-axis as a rotating axis, and forming a lower end face of a tuning fork groove 3 in a flat surface by a diamond wheel. With this constitution, even when T/W and W/T in which values of widths T and thicknesses T of arms 4, 5 are approached are 0.6 or more, vertical vibration in vibrating the tuning fork is prevented to suppress normal output, thereby improving a detecting accuracy of the crystal sensor. Even when only the center of the lower end face of the groove is flattened, similar effect can be expected. |
