Devices and techniques for cutting and coagulating tissue
Various embodiments are directed to a method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument. The method comprises generating at least one electrical signal. The at least one electrical signal is monitored against a first set of logic conditions. A first response is triggered when the first set of logic conditions is met. A parameter is determined from the at least one electrical signal.
1. A method of driving an ultrasonic end effector coupled to an ultrasonic drive system, the method comprising:
driving, by a generator, the ultrasonic end effector at a resonant frequency thereof;
monitoring, by the generator, the resonant frequency of the ultrasonic end effector;
incrementing, by the generator, a timer when the resonant frequency is less than a threshold frequency; and
comparing, by the generator, the timer to a required trigger time.
2. The method of claim 1 , further comprising setting a logic condition when the timer is greater than the required trigger time.
3. The method of claim 1 , further comprising resetting the timer when the resonant frequency is greater than the threshold frequency.
4. The method of claim 1 , further comprising triggering a first response when the resonant frequency crosses the threshold frequency.
5. The method of claim 4 , further comprising generating an audible feedback when the first response is triggered.
6. The method of claim 4 , further comprising generating a visual feedback when the first response is triggered.
7. The method of claim 4 , further comprising generating a tactile feedback when the first response is triggered.
8. A generator for driving an ultrasonic end effector of an ultrasonic drive system, the generator comprising a control circuit, configured to:
drive the ultrasonic end effector at a resonant frequency thereof;
monitor the resonant frequency of the ultrasonic end effector;
increment a timer when the resonant frequency is less than a threshold frequency; and
compare the timer to a required trigger time.
9. The generator of claim 8 , wherein the control circuit is further configured to set a logic condition when the timer is greater than the required trigger time.
10. The generator of claim 8 , wherein the control circuit is further configured to reset the timer when the resonant frequency is greater than the threshold frequency.
11. The generator of claim 8 , wherein the control circuit is further configured to trigger a first response when the resonant frequency crosses the threshold frequency.
12. The generator of claim 11 , wherein the control circuit is further configured to generate an audible feedback when the first response is triggered.
13. The generator of claim 11 , wherein the control circuit is further configured to generate a visual feedback when the first response is triggered.
14. The generator of claim 11 , wherein the control circuit is further configured to generate a tactile feedback when the first response is triggered.
15. A generator for driving an ultrasonic end effector of an ultrasonic drive system, the generator comprising a control circuit, configured to:
drive the ultrasonic end effector at a resonant frequency thereof;
monitor the resonant frequency of the ultrasonic end effector;
compare the resonant frequency of the ultrasonic end effector to a threshold frequency;
generate a first pulse amplitude for a first period over which the generator is driven; and
generate a second pulse amplitude for a second period over which the generator is driven.
16. The generator of claim 15 , wherein the control circuit is configured to increment a timer when the resonant frequency is less than a threshold frequency.
17. The generator of claim 16 , wherein the control circuit is further configured to compare the timer to a required trigger time.
18. The generator of claim 17 , wherein the control circuit is further configured to set a logic condition when the timer is greater than the required trigger time.
19. The generator of claim 16 , wherein the control circuit is further configured to reset the timer when the resonant frequency is greater than the threshold frequency.
20. The generator of claim 15 , wherein the control circuit is further configured to trigger a first response when the resonant frequency crosses the threshold frequency.