| 摘要 |
PURPOSE:To obtain a subminiature low frequency mechanical oscillator by decreasing the stiffness of a supporting line. CONSTITUTION:A piezoelectric thin film 21 is polarized as shown by arrows. When it is energized electrically from electric terminals 24 and 24', high-frequency-side energizing in secondary mode of inflection determined by the shape and size of an oscillator is carried out and mode conversion is performed; and energizing in mode of rigid body rotation shown by a broken line at an extremely low frequency side is carried out and a supporting line 23 is twisted to cause resonance. The resonance frequency of the rigid-body rotation mode is determined by stiffness regarding the torsion of the supporting line 23 while the resonance frequency of the inflection mode of a sound piece is determined by the size and shape of the sound piece. Therefore, even if the size of a part for rigid body rotation is reduced, the frequency is decreased freely by reducing the stiffness of the supporting line 23. |
