Composite longitudinal vibration mechanical filter's method of manufacturing including undesired vibration absorber

摘要

A method of manufacturing a composite longitudinal vibration mechanical filter that vibrates at a preselected central frequency in a high frequency range. The filter includes a plurality of vibratable bodies including input and output vibratable bodies each having respective piezoelectric members superposed thereon. Coupling elements couple the vibratable bodies to each other. Supporting elements project respectively from the input and output vibratable bodies. A holder is provided to which the supporting elements are attached. The method includes forming an integral body including the plurality of vibratable bodies, the coupling elements, the supporting elements, the holder and a vibration absorbing body holder for eliminating unnecessary vibrations. The vibration absorbing body holder is disposed between at least one of the vibratable bodies and the holder, and is disposed so as to absorb unnecessary vibrations which are transmitted to the output vibratable body, and to reduce unnecessary spurious responses occurring outside of a bandpass region of the filter. The piezoelectric members are fixedly superposed on the input and output vibratable bodies in sandwiching relation thereto, and respective electrodes are connected to the piezoelectric members.