초록 ▼

An ultrasonic generator comprising an ultrasonic transducer having a natural frequency at which the dynamic admittance becomes maximum; a main circuit consisting of a switching circuit or first current regulator and a second current regulator connected in series to said switching circuit or first cu

An ultrasonic generator comprising an ultrasonic transducer having a natural frequency at which the dynamic admittance becomes maximum; a main circuit consisting of a switching circuit or first current regulator and a second current regulator connected in series to said switching circuit or first current regulator, the ultrasonic transducer being interconnected between an electrical source and the junction between said switching circuit or first current regulator and the second current regulator; a driving circuit for alternately driving the switching circuit or first current regulator and the second current regulator at a frequency equal to or substantially equal to the natural frequency of the ultrasonic transducer, thereby supplying the driving current thereto; and a feedback circuit for deriving an AC voltage in proportion to the magnitude of the driving current and feeding back this voltage to the driving circuit.

대표청구항 ▼

An ultrasonic generator comprising: a constant current circuit including a first bipolar transistor whose emitter is connected to one end of a resistor and base is connected to one end of a constant-voltage regulating element, the other ends of said resistor and said constant-voltage regulating elem

An ultrasonic generator comprising: a constant current circuit including a first bipolar transistor whose emitter is connected to one end of a resistor and base is connected to one end of a constant-voltage regulating element, the other ends of said resistor and said constant-voltage regulating element being connected together; a first switching circuit including a second bipolar transistor whose base is connected to the base of said first transistor to form a complementary symmetry circuit with said first transistor; an ultrasonic transducer having a natural frequency at which the dynamic admittance thereof becomes maximum, said transducer being connected between one terminal of an electric power source and the junction of an output terminal of said switching circuit and an output terminal of said constant-current circuit; said output terminal being coupled to the emitters of said transistors; a second switching circuit whose output terminal is connected to the bases of said first and second transistors and adapted to drive the others of said circuits with a square wave having a frequency substantially equal to the natural frequency of said ultrasonic transducer; and a feedback circuit coupled between said transducer and said second switching circuit and adapted to provide an AC feedback voltage in proportion to the current flowing through said ultrasonic transducer to cause said generator to oscillate at said natural frequency.