Ultrasonic surgical instrument with dual modes

An apparatus for operating on tissue, the apparatus comprising:

• (a) a shaft assembly, wherein the shaft assembly defines a longitudinal axis, wherein the shaft assembly comprises:
• (i) an acoustic waveguide, wherein the waveguide is configured to acoustically couple with an ultrasonic transducer,
• (ii) a first translatable member comprising a first tube, wherein the first translatable member is configured to translate relative to the acoustic waveguide, and
• (iii) a second translatable member comprising a second tube, wherein the first tube and the second tube are coaxially aligned with each other about the longitudinal axis, wherein the second translatable member is configured to translate relative to the acoustic waveguide;
• and
• (b) an end effector, wherein the end effector comprises:
• (i) an ultrasonic blade in acoustic communication with the waveguide, and
• (ii) a clamp arm, wherein the clamp arm is configured to pivot about a first pivot point toward and away from the ultrasonic blade along a first angular path from a first position to a second position in response to translation of the first translatable member relative to the acoustic waveguide, wherein the clamp arm is further configured to pivot about a second pivot point toward and away from the ultrasonic blade along a second angular path from the second position to a third position in response to translation of the second translatable member relative to the body.

An apparatus for operating on tissue, the apparatus comprising:

• (a) a body;
• (b) a shaft assembly, wherein the shaft assembly extends distally from the body, wherein the shaft assembly defines a longitudinal axis, wherein the shaft assembly comprises:
• (i) an acoustic waveguide, wherein the waveguide is configured to acoustically couple with an ultrasonic transducer,
• (ii) a static member comprising first tube,
• (iii) a first translatable member comprising a second tube coaxially disposed with respect to the first tube, wherein the first translatable member is configured to translate relative to the body between a first position and a second position, and
• (iv) a second translatable member configured to translate with the first translatable member between the first position and the second position, wherein the second translatable member is configured to translate relative to the body and the first translatable member between the second position and a third position;
• and
• (c) an end effector, wherein the end effector comprises:
• (i) an ultrasonic blade in acoustic communication with the waveguide, and
• (ii) a clamp arm, wherein the clamp arm is configured to pivot relative to the ultrasonic blade between an open position, a first closed position, and a second closed position, wherein the first translatable member is configured to drive the clamp arm between the open position and the first closed position while translating from the first position to the second position, wherein the second translatable member is configured to drive the clamp arm between the first closed position and the second closed position while translating from the second position to the third position.