Patent ID: 6533792
Filing Date: 2003-03-18
Classification: A61B

Abstract:
A device for removing calculi by using an intracorporeal lithotripter, comprising:a metallic probe or sonotrode serving as a wave guide and being inserted into an operating passage of an endoscope for a fragmentation of calculi via a distal end of said metallic probe or sonotrode; an electrically controlled ultrasonic transducer for generating longitudinal oscillations, for being transferred to said metallic probe or sonotrode; the ultrasonic transducer comprising at least one piezoceramic disc which is arranged between a reflector and a horn that carries said metallic probe or sonotrode, the arrangement being fixedly interconnected by a traversing fastening stud bolt; the electrically controlled oscillations of said metallic probe or sonotrode as electrically controlled by said ultrasonic transducer being switchable between a periodically stimulated oscillation and a pulse wave stimulated oscillation of said metallic probe or sonotrode; wherein two separate first and second circuit systems are provided for controlling said periodic and said pulse wave stimulated oscillations, respectively, of said metallic probe or sonotrode, wherein a first circuit system for controlling the periodic oscillation of the metallic probe or sonotrode comprises a voltage-controlled oscillator which is connected via a voltage-to-frequency converter and an interconnected output amplifier to an impedance transformer, and a phase comparator which is arranged for comparing the phases of the output voltage and the output current of the impedance transformer to thereby generate a control voltage for the oscillator; and wherein a second circuit system for controlling the pulse wave stimulated oscillation of the metallic probe or sonotrode comprises a voltage source and a capacitor which are interconnected via a change-over switch, said change-over switch being arranged for coupling the second circuit system with the ultrasonic transducer.