Activation features for ultrasonic surgical instrument

An ultrasonic surgical instrument, comprising:

• (a) a body, wherein the body defines a longitudinal axis, wherein the body is configured to receive an ultrasonic transducer;
• (b) a shaft assembly, wherein the shaft assembly comprises an acoustic waveguide;
• (c) an ultrasonic blade, wherein the ultrasonic blade is in acoustic communication with the acoustic waveguide;
• and
• (d) an actuation assembly, wherein the actuation assembly comprises:
• (i) a first activation circuit, wherein the first activation circuit is configured transition between a deactivated state and a first activated state, wherein the first activation circuit is configured to activate the ultrasonic blade at a first energy level in the first activated state;
• (ii) a first annular activator corresponding to the first activation circuit, wherein the first annular activator extends angularly about the body along a 360 degree angular range in a first plane, wherein the first annular activator is configured to move laterally relative to the longitudinal axis of the body in any radial direction from the longitudinal axis in the first plane to transition the first activation circuit from the deactivated state to the first activated state, and
• (iii) a camming assembly configured to resiliently bias the first annular activator in any radial direction from the longitudinal axis in the first plane toward a position associated with the first activation circuit being in the deactivated state.

An ultrasonic surgical instrument, comprising:

• (a) a body, wherein the body defines a longitudinal axis, wherein the body is configured to receive an ultrasonic transducer;
• (b) a shaft assembly, wherein the shaft assembly comprises an acoustic waveguide;
• (c) an ultrasonic blade, wherein the ultrasonic blade is in acoustic communication with the acoustic waveguide;
• and
• (d) an actuation assembly, wherein the actuation assembly comprises:
• (i) a first activation circuit, wherein the first activation circuit is configured transition between a deactivated state and a first activated state, wherein the first activation circuit is configured to activate the ultrasonic blade at a first energy level in the first activated state;
• (ii) a first annular activator corresponding to the first activation circuit, wherein the first annular activator extends angularly about the body along a 360 degree angular range in a first plane, wherein the first annular activator is configured to move laterally within the first plane relative to the longitudinal axis of the body in a first radial direction, a second radial direction, and a third radial direction to transition the first activation circuit from the deactivated state to the first activated state, and
• (iii) a camming assembly configured to resiliently bias the first annular activator in the first radial direction, the second radial direction, and the third radial direction toward a position associated with the first activation circuit being in the deactivated state.

A method of using an ultrasonic surgical instrument, comprising:

• (a) grasping a body housing a waveguide, wherein the waveguide is in ultrasonic communication with an ultrasonic blade, wherein the body defines a longitudinal axis;
• (b) pressing a first annular activator in a first radial direction relative to the longitudinal axis to activate a first activation circuit to thereby activate the ultrasonic blade at a first energy level, wherein the first radial direction is within a first plane;
• (c) pressing the first annular activator in a second radial direction relative to the longitudinal axis to activate the first activation circuit to thereby activate the ultrasonic blade at the first energy level, wherein the second radial direction is within the first plane, wherein the second radial direction is different than the first radial direction;
• and
• (d) pressing the first annular activator in a third radial direction relative to the longitudinal axis to activate the first activation circuit to thereby activate the ultrasonic blade at the first energy level, wherein the third radial direction is within the first plane, wherein the third radial direction is different than the second radial direction and the first radial direction.