Patent ID: 6897628

Claim:
Apparatus for generating ultrasonic vibration, said apparatus comprising: an ultrasonic horn, an ultrasonic transducer operatively joined to said ultrasonic horn to generate mechanical vibrations and to transmit vibrations so generated to said ultrasonic horn, said ultrasonic transducer comprising: first and second drive prongs of magnetostrictive material wound with drive coils, said drive coils arranged to produce magnetostrictive forces in said drive prongs in response to voltages applied across said drive coils, and a sensing magnet of magnetostrictive material wound with a sensing coil, said sensing magnet arranged such that vibrations produced in said drive prongs as a result of said magnetostrictive forces are transmitted to said sensing magnet and generate an oscillating voltage in said sensing coil, a power source for supplying periodically varying voltages across said drive coils, and control means for detecting a maximum voltage generated in said sensing coils, comparing said maximum voltage with a target value, and adjusting said voltages applied across said drive coils as needed to achieve said target value.