Patent ID: 8779648
Filing Date: 2014-07-15
Classification: A61B,B06B

Abstract:
1. A method for driving an end effector coupled to an ultrasonic drive system of a surgical instrument, the method comprising: generating a first ultrasonic drive signal by a generator coupled to an ultrasonic drive system, wherein the ultrasonic drive system comprises an ultrasonic transducer coupled to a waveguide and an end effector coupled to the waveguide, and wherein the ultrasonic drive system is configured to resonate at a resonant frequency; actuating the ultrasonic transducer with the first ultrasonic drive signal for a first period; generating a second ultrasonic drive signal by the generator; and actuating the ultrasonic transducer with the second ultrasonic drive signal for a second period, subsequent to the first period; wherein the first drive signal is different from the second drive signal over the respective first and second periods; and wherein the first and second drive signals define a step function waveform over the first and second periods.