Electrosurgical and ultrasonic surgical system

Claim 1

In an electrical circuit system which provides electrical energy to a surgical apparatus for performing one or more surgical procedures at a surgical site on a patient, which apparatus comprises a handpiece, a tool supported by said handpiece, said tool having a vibrating tool tip with a tool passageway therethrough terminating in a tip opening, vibrating means for ultrasonically vibrating said tool tip and suction means for applying aspiration to aspirate tissue particles and fluid away from the surgical site and through said tip opening and tool passageway; which system comprises RF current means selectively operable for providing an RF current to said tool tip for allowing performance of an electrosurgical procedure at the surgical site; said RF current means including a generator having a pulse drive and RF amplifier section, and switching means for switching the RF current provided to said tool tip to at least an RF coagulating current during ultrasonic vibration, the improvement wherein said system includes means for providing feedback control of the output energy provided by said drive comprising an impedance sensing network which automatically acts to reduce the RF output energy as load impedance increases, whereby RF leakage current is restrained to a safe low level.