An ultrasonic motion generator includes a non-resonant inverter, an ultrasonic transducer, and a comparator. The non-resonant inverter inverts direct current (DC) to alternating current (AC) having a first frequency. The ultrasonic transducer is electrically coupled with the non-resonant inverter and generates an ultrasonic motion based on the inverted AC. The comparator automatically detects a deviation of the first frequency from a resonant frequency of the ultrasonic transducer based on motion current passing through the ultrasonic transducer and generates an output signal based on the deviation to drive the non-resonant inverter.

A surgical system is disclosed including an end effector, a control circuit, a closure member, and a firing member. The end effector includes a first jaw, a second jaw, and an electrode. The first jaw is rotatable relative to the second jaw between an open position and a close position to capture tissue therebetween. The electrode is configured to conduct a sub-therapeutic RF current to the tissue. The control circuit is operably coupled to the electrode. The control circuit is configured to measure impedance of the tissue over time based on the sub-therapeutic RF current. The closure member is configured to move the first jaw towards the second jaw at a closure rate based on the impedance of the tissue. The firing member is configured to move within the end effectors towards a fired position at a firing rate based on the impedance of the tissue.

A surgical instrument includes a body, a shaft assembly, and an end effector. The end effector includes an ultrasonic blade and a clamp arm movably coupled with the shaft assembly. The shaft assembly extends between the body and the end effector and includes an acoustic waveguide, a rotational driver, and a driver wrench. The rotational driver is configured to be received within the rotational drive channel and rotate the shaft assembly relative to the body. The acoustic waveguide includes a notch and the driver wrench includes a key, wherein the first notch of the acoustic waveguide is configured to receive the key.

A surgical instrument end effector assembly includes a first jaw member defining an insulative tissue-contacting surface and first and second electrically-conductive tissue-contacting surfaces disposed on either side of the insulative tissue-contacting surface. A second jaw member includes an ultrasonic blade body positioned to oppose the insulative tissue-contacting surface of the first jaw member. The first jaw member is movable relative to the second jaw member between a spaced-apart position and an approximated position to apply a first grasping force to tissue disposed therebetween. A slider is movable, independent of the first jaw member, between a retracted position, wherein the slider is disposed proximally of the first and second jaw members, and an extended position, wherein the slider extends about the first jaw member and urges the first jaw member from the approximated position further towards the second jaw member to apply a second, greater grasping force to tissue.

An ultrasonic treatment includes: a vibration transmission portion configured to vibrate by receiving ultrasonic waves, and transmit vibration to a treatment target; a sheath that includes a first through hole in which the vibration transmission portion is inserted while a distal end of the vibration transmission portion is exposed, and a second through hole that has a hole shape penetrating in a different direction from a penetration direction of the first through hole; a jaw that includes a first hole portion in which the sheath is inserted and a second hole portion configured to communicate with the second through hole; and a shaft that includes a space in which the vibration transmission portion is inserted, and that allows the jaw to rotate relative to the sheath when the shaft is inserted in the second through hole and the second hole portion.

An ultrasonic surgical instrument including a blade that treats tissue and a fluid control system to cool the blade by pumping cooling fluid through the blade. The blade defines a blade lumen in fluid contact with an inflow and return conduit of the fluid control system. The inflow conduit defines an open distal end positioned within the blade lumen adjacent the distal end of the blade lumen and the return conduit defines an open distal end positioned within the blade lumen adjacent the proximal end of the blade lumen. The fluid control system may further include a fluid reservoir holding the cooling fluid and an inflow pump. The inflow pump is configured to deliver the fluid from the fluid reservoir, through the inflow conduit and the blade lumen, and into return conduit.

An apparatus for operating on tissue includes a body assembly, a shaft, an acoustic waveguide, and an end effector. The end effector includes an ultrasonic blade, a clamp arm, and a blade guard. The ultrasonic blade is in acoustic communication with the waveguide. The clamp arm is configured to pivot toward and away from the ultrasonic blade. The clamp arm has a first tine. The blade guard extends from the shaft. The blade guard has a longitudinally extending arm defining a concave pathway and a second tine located distal to the longitudinally extending arm. The ultrasonic blade is partially housed within the concave pathway. The first tine and the second tine are configured to grasp tissue when the clamp arm pivots toward the ultrasonic blade.

An apparatus comprises a body assembly, a shaft, an acoustic waveguide, an articulation section, an end effector, and an articulation drive assembly. The shaft extends distally from the body assembly and defines a longitudinal axis. The acoustic waveguide comprises a flexible portion. The articulation section is coupled with the shaft. A portion of the articulation section encompasses the flexible portion of the waveguide. The articulation section comprises a plurality of body portions aligned along the longitudinal axis and a flexible locking member. The flexible locking member is operable to secure the body portions in relation to each other and in relation to the shaft. The end effector comprises an ultrasonic blade in acoustic communication with the waveguide. The articulation drive assembly is operable to drive articulation of the articulation section to thereby deflect the end effector from the longitudinal axis.

A surgical instrument is disclosed. The surgical instrument comprises an end effector comprising an ultrasonic blade and a clamp arm. The clamp arm is movable relative to the ultrasonic blade to transition the end effector between an open configuration and a closed configuration to clamp tissue between the ultrasonic blade and the clamp arm. The surgical instrument further comprises an ultrasonic transducer configured to generate an ultrasonic energy output and a waveguide configured to transmit the ultrasonic energy output to the ultrasonic blade. The surgical instrument further comprises a control circuit, configured to detect an immersion of the end effector in a liquid and compensate for heat flux lost due to the immersion of the end effector in the liquid.

A method of controlling the temperature of an ultrasonic blade includes applying a power level to an ultrasonic transducer to achieve a desired temperature at an ultrasonic blade coupled to the transducer via an ultrasonic waveguide, inferring a temperature of the blade based on a voltage V.sub.g(t) signal and a current I.sub.g(t) signal applied to the transducer, comparing the inferred temperature of the blade to a predetermined temperature; and adjusting the power level to the transducer based on the comparison. In some aspects, the method includes measuring a phase angle φ between the voltage V.sub.g(t) and the current I.sub.g(t) and inferring the temperature of the blade from the phase angle φ. In some aspects, the method includes measuring an impedance Z.sub.g(t) equal to a ratio of the voltage V.sub.g(t) to the current I.sub.g(t) and inferring the temperature of the blade from the impedance Z.sub.g(t).