| 摘要 |
PURPOSE:To increase the anti-shock performance, by forming the built-in part at the groove bottom of the base of the tuning fork type crystal oscillator formed with chemical etching processing and setting the cross section width 1/2 or less of the crystal oscillator thickness. CONSTITUTION:The natural surface 3c of the crystal is present at the upper part of the groove bottom of the base 3b of the tuning fork type crystal oscillator 3, and the built-in part 3d is set not more than about a half the thicknesst of the resonant branch 3a. With this construction, if the inpact load B is applied, the concentrated stress in stress distrubition can be mitigated. Accordingly, since the centralization of stress around the groove bottom is mitigated at resonance, leakage vibration is reduced to enable to increase the resonant sharpness. |
