Drive circuit for piezoelectric transducer in ink jet printers

Claim 1

Apparatus for driving a piezoelictric transducer surrounding a fluid ink path in an ink jet printer, said transducer being adapted to expand upon application of a voltage poled opposite to the polarization direction of the transducer, and constricting in response to application of an oppositely poled voltage, including, in combination; a resonant circuit having a two-terminal inductor and a piexoelectric transducer functioning as a capacitance, means including a transistor having its collector conductively connected to said inductor for exciting said inductor directly by means of a current pulse having a predetermined duration flowing between its two terminals, the waveform of the voltage applied to said piezoelectric transducer being determined by the shape of said current pulse, and including a damping circuit connected in series with said inductor for damping the voltage waveform applied to said transducer, said damping beginning after a time interval delay relative to the beginning of oscillation of said resonant circuit initiated by said current pulse and damping said voltage waveform after the conclusion of said current pulse.