Methods and features for coupling ultrasonic surgical instrument components together

Inventors

Kimball, Cory G. • Witt, David A. • Clem, William E. • Grubbs, Nathan D. • Prenger, Daniel J. • Madan, Ashvani K.

Assignees

SAEC/KINETIC VISION Inc • STRATEGIXVISION Inc • Cilag GmbH International

Abstract

A surgical apparatus comprises a transducer assembly and a shaft assembly. The transducer assembly is operable to convert electrical power into ultrasonic vibrations. The shaft assembly comprises an ultrasonic waveguide, a sheath, a shroud, and a torque transfer assembly. The waveguide is configured to couple with the transducer assembly. The waveguide is disposed within the sheath. The sheath extends through the shroud. The torque transfer assembly is contained within the shroud. The torque transfer assembly is configured to transfer a predetermined range of torque from the shroud to the waveguide to thereby couple the waveguide with the transducer assembly. The torque transfer assembly is further configured to prevent transfer of torque from the shroud to the waveguide beyond an upper limit of the predetermined range.

Core Innovation

The invention relates to ultrasonic surgical instruments and surgical kits that include a transducer assembly operable to convert electrical power into ultrasonic vibrations, and an ultrasonic waveguide configured to couple with the transducer assembly. The ultrasonic waveguide has a distal end forming a blade, and a cap is removably disposed on the blade to secure the cap to the blade using resilient features or a friction fitting. The kit further includes a torque wrench operable to drive rotation of the waveguide to couple the waveguide with the transducer assembly.

A core aspect of the invention is a torque transfer and torque-limiting arrangement that restricts the amount of torque by which the waveguide may be coupled with the transducer assembly. The torque limiting feature is operable to prevent exceeding a predetermined torque range or upper limit, including embodiments with snap-fit cap engagement and audible and/or tactile torque signaling. In multiple structures, the torque wrench includes a cap engagement feature with resilient latch members and inwardly extending tabs configured to contact a proximally facing surface of the cap, such that distal movement removes the cap from the blade.

The invention also describes alternative coupling and retention structures for transferring torque while controlling cap retention and removal. Examples include threaded interfaces where a threaded stud couples with a threaded bore of the ultrasonic waveguide, and other mechanical couplings that include a shroud, retaining rings, resilient features, ratcheting pawl and collar, or bayonet-like mounting. These arrangements are described as restricting torque to an upper limit while also providing feedback related to torque limiting and supporting removable cap behavior by actuating distally to drive the cap away from the blade by overcoming biasing or friction.

Claims Coverage

The independent claims (three total) cover a surgical ultrasonic kit architecture with a transducer assembly, an ultrasonic waveguide/blade, a removably mounted blade cap, and a torque wrench that drives waveguide rotation to couple with the transducer assembly while using a torque limiting feature and a resilient cap engagement function. Across the independent claims, the key inventive focus is on torque wrench driven coupling with torque restriction, and the specific resilient or friction-based mechanisms for cap retention and removal by distal actuation.

The independent claims consistently require a transducer assembly converting electrical power into ultrasonic vibrations, an ultrasonic waveguide forming a blade, a removably mounted cap, and a torque wrench that couples the waveguide to the transducer assembly while restricting torque via a torque limiting feature. The main differentiator among the independent claims is the cap retention and removal mechanism: resilient latch engagement removing the cap, friction fitting overcome by resilient distal cap engagement, or resiliently biased cap retention overcome by a resilient, flexible cap engagement feature actuated distally.

Stated Advantages

Documented Applications