Patent ID: 6289736
Filing Date: 2001-09-18
Classification: B06B,B23K

Abstract:
A method of driving a loaded electroacoustic transducer at discontinuous intervals with electric excitation impulses supplied to the transducer at one of a determined resonant frequency or frequency multiple thereof to induce mechanical oscillations of the transducer for impacting a work interface presenting variable loading factors while confining duration of said impulses to not more than half a period of said mechanical oscillations, wherein the excitation impulses are discontinuously interrupted while the transducer is impacting said work interface, comprising the steps of:attaining a feedback voltage from the driven transducer when impacting said work interface representative of the displacement of the transducer and its intrinsic mechanical oscillation frequency and phase,resuming the excitation impulses after interruptions at a phase corresponding to the highest loaded transducer sensitivity providing for maximum values of ultrasonic displacement amplitude at varying loads, andadjusting the oscillator frequency and phase at the resumption of the excitation impulses to match the frequency and phase exhibited by the intrinsic mechanical oscillation frequency of the driven transducer at the resumption time.