Patent Description:
Such surgical instruments may be directly gripped and manipulated by a surgeon or incorporated into a robotically assisted surgery. During robotically assisted surgery, the surgeon typically operates a master controller to remotely control the motion of such surgical instruments at a surgical site. The controller may be separated from the patient by a significant distance (e.g., across the operating room, in a different room, or in a completely different building than the patient). Alternatively, a controller may be positioned quite near the patient in the operating room. Regardless, the controller typically includes one or more hand input devices (such as joysticks, exoskeletol gloves, master manipulators, or the like), which are coupled by a servo mechanism to the surgical instrument. In one example, a servo motor moves a manipulator supporting the surgical instrument based on the surgeon's manipulation of the hand input devices. During the surgery, the surgeon may employ, via a robotic surgical system, a variety of surgical instruments including an ultrasonic blade, a tissue grasper, a needle driver, an electrosurgical cautery probes, etc. Each of these structures performs functions for the surgeon, for example, cutting tissue, coagulating tissue, holding or driving a needle, grasping a blood vessel, dissecting tissue, or cauterizing tissue.

Document <CIT> discloses a surgical instrument comprising an articulable harmonic waveguide. The articulable harmonic waveguide comprises a first drive section comprising a proximal end and a distal end. The proximal end of the first drive section may be configured to connect to an ultrasonic transducer. The articulable harmonic waveguide further comprises a first flexible waveguide coupled to the distal end of the first drive section. An end effector extends distally from the first flexible waveguide. The surgical instrument further comprises an articulation actuator to flex the first flexible waveguide. In some examples, the articulable harmonic waveguides comprise a total curvature limiter. The total curvature limiter may comprise a mechanical or electrical break to prevent the articulable harmonic waveguide from exceeding one or more predetermined conditions. The mechanical breaks are formed on the waveguide.

Document <CIT>discloses articulating surgical instruments for treating tissue comprising an end effector and a shaft extending proximally from the end effector along a longitudinal axis. In certain examples, the shaft comprises a plurality of transverse spacer members as well as first and second rotatable members extending through at least a portion of the plurality of transverse spacer members. The first and second rotatable members may both be biased away from the longitudinal axis such that their respective directions of bias vary with rotation of the first rotatable member. When the respective directions of bias of the first and second rotatable members oppose one another, the shaft may be substantially straight. When the respective directions of bias of the first and second rotatable members are aligned with one another, the shaft may articulate away from the longitudinal axis in the direction of the alignment.

Document <CIT> discloses surgical instruments for use in handheld applications or with robotic surgical systems. The surgical instruments may comprise an end effector to treat tissue and a shaft extending proximally from the end effector along a longitudinal axis. Some embodiments may be usable with an instrument mounting portion of a robotic surgical instrument. For example, the shaft may extend proximally to the instrument mounting portion.

While several surgical instruments and systems have been made and used, it is believed that no one prior to the inventors has made or used the invention defined in the appended claims.

For clarity of disclosure, the terms "proximal" and "distal" are defined herein relative to a human or robotic operator of the surgical instrument. The term "proximal" refers the position of an element closer to the human or robotic operator of the surgical instrument and further away from the surgical end effector of the surgical instrument. The term "distal" refers to the position of an element closer to the surgical end effector of the surgical instrument and further away from the human or robotic operator of the surgical instrument. It will be further appreciated that, for convenience and clarity, spatial terms such as "front," "rear," "clockwise," "counterclockwise," "longitudinal," and "transverse" also are used herein for reference to relative positions and directions. Such terms are used below with reference to views as illustrated for clarity and are not intended to limit the invention described herein.

<FIG> shows an exemplary surgical instrument, such as an ultrasonic surgical instrument (<NUM>). At least part of ultrasonic surgical instrument (<NUM>) may be constructed and operable in accordance with at least some of the teachings of any of the various patents, patent application publications, and patent applications that are cited herein. As described therein and as will be described in greater detail below, ultrasonic surgical instrument (<NUM>) is operable to cut tissue and seal or weld tissue (e.g., a blood vessel, etc.) substantially simultaneously.

Ultrasonic surgical instrument (<NUM>) of the present example comprises a body assembly, such as a first exemplary base assembly (<NUM>), a shaft assembly (<NUM>), and an end effector (<NUM>). Base assembly (<NUM>) includes a housing (<NUM>), a button (<NUM>), and a pair of latch clasps (<NUM>). Button (<NUM>) is operatively connected to an electrical base power controller (not shown) and configured to selectively power ultrasonic surgical instrument (<NUM>) for use. In addition, housing (<NUM>) of the present example includes a front housing cover (<NUM>) and a rear housing cover (<NUM>) removably secured together via latch clasps (<NUM>). More particularly, latch clasps (<NUM>) removably secure front housing cover (<NUM>) to rear housing cover (<NUM>) such that front housing cover (<NUM>) may be removed for accessing an interior space (<NUM>) (see <FIG>) within base assembly (<NUM>). Shaft assembly (<NUM>) distally extends from base assembly (<NUM>) to end effector (<NUM>) to thereby communicate mechanical and/or electrical forces therebetween for use as will be discussed below in greater detail. As shown in the present example, base assembly (<NUM>) is configured to operatively connect to a robotic drive (not shown) for driving various features of shaft assembly (<NUM>) and/or end effector (<NUM>). However, in another example, body assembly may alternatively include a handle assembly (not shown), which may include a pistol grip (not shown) in one example, configured to be directly gripped and manipulated by the surgeon for driving various features of shaft assembly (<NUM>) and/or end effector (<NUM>). The invention is thus not intended to be unnecessarily limited to use with base assembly (<NUM>) and the robotic drive (not shown).

To this end, with respect to <FIG>, base assembly (<NUM>) includes a robotic driven interface (<NUM>) extending through a base plate (<NUM>) of rear housing cover (<NUM>) and configured to mechanically couple with the robotic drive (not shown). Robotic driven interface (<NUM>) of the present example includes a plurality of instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) having a plurality of input bodies (38a, 38b, 38c, 38d, 38e, 38f), respectively. Each input body (38a, 38b, 38c, 38d, 38e, 38f), which may also be referred to herein as a "puck," is configured to removably connect with the robotic drive (not shown) and, in the present example, is generally cylindrical and rotatable about an axis. Input bodies (38a, 38b, 38c, 38d, 38e, 38f) have a plurality of slots (<NUM>) configured to receive portions of the robotic drive (not shown) for gripping and rotatably driving input bodies (38a, 38b, 38c, 38d, 38e, 38f) in order to direct operation of shaft assembly (<NUM>) and/or end effector (<NUM>) as will be discussed below in greater detail. Base assembly (<NUM>) also receives an electrical plug (<NUM>) operatively connected to an electrical power source (not shown) to provide electrical power to base assembly (<NUM>) for operation as desired, such as powering electrical base power controller (not shown) and directing electrical energy to various features of shaft assembly (<NUM>) or end effector (<NUM>) associated with cutting, sealing, or welding tissue.

As best seen in <FIG>, end effector (<NUM>) of the present example includes a clamp arm (<NUM>) and an ultrasonic blade (<NUM>). Clamp arm (<NUM>) has a clamp pad (<NUM>) secured to an underside of clamp arm (<NUM>), facing blade (<NUM>). In one example, clamp pad (<NUM>) may comprise polytetrafluoroethylene (PTFE) and/or any other suitable material(s). Clamp arm (<NUM>) is pivotally secured to a distally projecting tongue (<NUM>) of shaft assembly (<NUM>). Clamp arm (<NUM>) is operable to selectively pivot toward and away from blade (<NUM>) to selectively clamp tissue between clamp arm (<NUM>) and blade (<NUM>). A pair of arms (<NUM>) extend transversely from clamp arm (<NUM>) and are pivotally secured to another portion of shaft assembly (<NUM>) configured to longitudinally slide to pivot clamp arm (<NUM>) as indicated by an arrow (<NUM>) between a closed position shown in <FIG> and an open position shown in <FIG>.

In addition to pivoting relative to blade (<NUM>), clamp arm (<NUM>) of the present example is further configured to rotate about blade (<NUM>) relative to blade (<NUM>) and also relative to shaft assembly (<NUM>) as indicated by an arrow (<NUM>). In one example, clamp arm (<NUM>) rotates in the clockwise or counterclockwise directions completely around blade (<NUM>) and may be selectively fixed in any angular position relative to blade (<NUM>) for directing clamp arm (<NUM>) from the open position to the closed position for clamping tissue. In another example, clamp arm (<NUM>) may have rotational stops (not shown) configured to limit rotational movement of clamp arm (<NUM>) relative to blade (<NUM>) in one or more predetermined positions.

Blade (<NUM>) of the present example is operable to vibrate at ultrasonic frequencies in order to effectively cut through and seal tissue, particularly when the tissue is being compressed between clamp pad (<NUM>) and blade (<NUM>). Blade (<NUM>) is positioned at a distal end of an acoustic drivetrain. This acoustic drivetrain includes a transducer assembly (<NUM>) (see <FIG>) and an acoustic waveguide (<NUM>), which includes a flexible portion (<NUM>) discussed below in greater detail. It should be understood that waveguide (<NUM>) may be configured to amplify mechanical vibrations transmitted through waveguide (<NUM>). Furthermore, waveguide (<NUM>) may include features operable to control the gain of the longitudinal vibrations along waveguide (<NUM>) and/or features to tune waveguide (<NUM>) to the resonant frequency of the system. Various suitable ways in which waveguide (<NUM>) may be mechanically and acoustically coupled with transducer assembly (<NUM>) (see <FIG>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

Those of ordinary skill in the art will understand that, as a matter of physics, a distal end of blade (<NUM>) is located at a position corresponding to an antinode associated with resonant ultrasonic vibrations communicated through flexible portion (<NUM>) of waveguide (<NUM>). When transducer assembly (<NUM>) (see <FIG>) is energized, the distal end of blade (<NUM>) is configured to move longitudinally in the range of, for example, approximately <NUM> to <NUM> micrometers peak-to-peak, and in some instances in the range of about <NUM> to about <NUM> micrometers at a predetermined vibratory frequency fo of, for example, <NUM>. When transducer assembly (<NUM>) (see <FIG>) of the present example is activated, these mechanical oscillations are transmitted through waveguide (<NUM>) to reach blade (<NUM>), thereby providing oscillation of blade (<NUM>) at the resonant ultrasonic frequency. Thus, when tissue is secured between blade (<NUM>) and clamp pad (<NUM>), the ultrasonic oscillation of blade (<NUM>) may simultaneously sever the tissue and denature the proteins in adjacent tissue cells, thereby providing a coagulative effect with relatively little thermal spread. In some versions, end effector (<NUM>) is operable to apply radiofrequency (RF) electrosurgical energy to tissue in addition to applying ultrasonic energy to tissue. In any case, other suitable configurations for an acoustic transmission assembly and transducer assembly (<NUM>) will be apparent to one of ordinary skill in the art in view of the teachings herein. Similarly, other suitable configurations for end effector (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings herein.

As shown in <FIG>, shaft assembly (<NUM>) includes a proximal shaft portion (<NUM>) extending along a longitudinal axis (<NUM>), a distal shaft portion (<NUM>) distally projecting relative to the proximal shaft portion (<NUM>), and an articulation section (<NUM>) extending between proximal and distal shaft portions (<NUM>, <NUM>). Shaft assembly (<NUM>) is configured to rotate about longitudinal axis (<NUM>) as indicated by an arrow (<NUM>). In one example, shaft assembly (<NUM>) rotates in the clockwise or counterclockwise directions completely around longitudinal axis (<NUM>) and may be selectively fixed in any rotational position about longitudinal axis (<NUM>) for positioning articulation section (<NUM>) and/or end effector (<NUM>) about longitudinal axis (<NUM>). While end effector (<NUM>) generally rotates with shaft assembly (<NUM>) as indicated by arrow (<NUM>), end effector (<NUM>) may be simultaneously and independently rotated as indicated by arrow (<NUM>) relative to shaft assembly (<NUM>) during use for repositioning portions of shaft assembly (<NUM>) and/or end effector (<NUM>) as desired.

Articulation section (<NUM>) is configured to selectively position end effector (<NUM>) at various lateral deflection angles relative to longitudinal axis (<NUM>) defined by proximal shaft portion (<NUM>). Articulation section (<NUM>) may take a variety of forms. In the present example, articulation section (<NUM>) includes a proximal link (<NUM>), a distal link (<NUM>), and a plurality of intermediate links (<NUM>) connected in series between proximal and distal links (<NUM>, <NUM>). Articulation section (<NUM>) further includes a pair of articulation bands (<NUM>) extending along a pair of respective channels (<NUM>) collectively defined through links (<NUM>, <NUM>, <NUM>). Links (<NUM>, <NUM>, <NUM>) are generally configured to pivot relative to each other upon actuation of articulation bands (<NUM>) to thereby bend articulation section (<NUM>) with flexible portion (<NUM>) of waveguide (<NUM>) therein to achieve an articulated state. By way of example only, articulation section (<NUM>) may alternatively or additionally be configured in accordance with one or more teachings of <CIT>, the disclosure of which is referred to herein. As another merely illustrative example, articulation section (<NUM>) may alternatively or additionally be configured in accordance with one or more teachings of <CIT>, entitled "Surgical Instruments with Articulating Shafts," the disclosure of which is referred to herein and <CIT>, entitled "Flexible Harmonic Waveguides/Blades for Surgical Instruments," the disclosure of which is referred to herein. In addition to or in lieu of the foregoing, articulation section (<NUM>) and/or may be constructed and/or operable in accordance with at least some of the teachings of <CIT>. Alternatively, articulation section (<NUM>) may be constructed and/or operable in any other suitable fashion.

Links (<NUM>, <NUM>, <NUM>) shown in <FIG> pivotally interlock to secure distal shaft portion (<NUM>) relative to proximal shaft portion (<NUM>) while allowing for deflection of distal shaft portion (<NUM>) relative to longitudinal axis (<NUM>). In the present example, proximal link (<NUM>) is rigidly connected to proximal shaft portion (<NUM>) and has a pair of arcuate grooves (<NUM>) opposed from each other. Intermediate links (<NUM>) respectively have a pair of arcuate tongues (<NUM>) proximally extending therefrom and a pair of arcuate grooves (<NUM>) positioned distally opposite from respective tongues (<NUM>). Each intermediate link (<NUM>) has tongues (<NUM>) pivotally received within adjacent arcuate grooves (<NUM>) of another intermediate link (<NUM>) or proximal link (<NUM>) as applicable. Distal link (<NUM>) is rigidly connected to distal shaft portion (<NUM>) and has another pair of arcuate tongues (<NUM>) opposed from each other and pivotally received within adjacent arcuate grooves (<NUM>) of intermediate link (<NUM>). Tongues (<NUM>) and grooves (<NUM>) connect together to form the series of interlocked links (<NUM>, <NUM>, <NUM>).

Distal link (<NUM>) further includes a pair of opposing notches (<NUM>) with a pin (<NUM>) therein configured to receive distal end portions of respective articulation bands (<NUM>). More particularly, pins (<NUM>) extend through a hole in each respective articulation bands (<NUM>) while distal end portions of respective articulation bands (<NUM>) are coupled within notches (<NUM>). Slots (<NUM>) in each of intermediate and proximal links (<NUM>, <NUM>) longitudinally align with each other and notches (<NUM>) to collectively define channels (<NUM>) configured to receive articulation bands (<NUM>) while allowing articulation bands (<NUM>) to slide relative to links (<NUM>, <NUM>, <NUM>). To this end, when articulation bands (<NUM>) translate longitudinally in an opposing fashion, this will cause articulation section (<NUM>) to bend, thereby laterally deflecting end effector (<NUM>) away from the longitudinal axis (<NUM>) of proximal shaft portion (<NUM>) from a straight configuration as shown in <FIG> to a first articulated configuration as shown in <FIG> and indicated by an arrow (<NUM>) or a second articulated configuration as shown in <FIG> and indicated by an arrow (<NUM>). In particular, end effector (<NUM>) will be articulated toward the articulation band (<NUM>) that is being pulled proximally. During such articulation, the other articulation band (<NUM>) may be pulled distally. Alternatively, the other articulation band (<NUM>) may be driven distally by an articulation control. Furthermore, flexible acoustic waveguide (<NUM>) is configured to effectively communicate ultrasonic vibrations from waveguide (<NUM>) to blade (<NUM>) even when articulation section (<NUM>) is in an articulated configuration as shown in <FIG>.

<FIG> shows interior space (<NUM>) of base assembly (<NUM>) with instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) in greater detail. Generally, instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) are engaged with shaft assembly (<NUM>) and configured to direct movement of end effector (<NUM>) and/or shaft assembly (<NUM>), such as movement indicated above in one example by arrows (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) (see <FIG>). Shaft assembly (<NUM>) is received within base assembly (<NUM>) and supported by bearings (<NUM>) therein to operatively connect each respective instrument actuator (36a, 36b, 36c, 36d, 36e, 36f) to shaft assembly (<NUM>) as well as operatively connect acoustic waveguide (<NUM>) (see <FIG>) to transducer assembly (<NUM>) and a generator (not shown) of the acoustic drivetrain. More particularly, transducer assembly (<NUM>) is coupled with generator (not shown) such that transducer assembly (<NUM>) receives electrical power from generator (not shown). Piezoelectric elements (not shown) in transducer assembly (<NUM>) convert that electrical power into ultrasonic vibrations. Generator (not shown) may be coupled to the electrical power source (not shown) via electrical plug (<NUM>) (see <FIG>) and a control module (not shown) that are configured to provide a power profile to transducer assembly (<NUM>) that is particularly suited for the generation of ultrasonic vibrations through transducer assembly (<NUM>). By way of example only, generator (not shown) may comprise a GEN04 or GEN11 sold by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. In addition or in the alternative, generator (not shown) may be constructed in accordance with at least some of the teachings of <CIT>, the disclosure of which is referred to herein. Still other suitable forms that generator (not shown) may take, as well as various features and operabilities that generator (not shown) may provide, will be apparent to those of ordinary skill in the art in view of the teachings herein.

The present example of base assembly (<NUM>) shown in <FIG> includes six instrument actuators (36a, 36b, 36c, 36d, 36e, 36f), although it will be appreciated that any such number of such instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) configured to direct movement of shaft assembly (<NUM>) and/or end effector (<NUM>) may be similarly used. As shown with respect to operation of ultrasonic surgical instrument (<NUM>), instrument actuator (36a) is more particularly a roll system actuator (36a) configured to rotate shaft assembly (<NUM>) about longitudinal axis (<NUM>). In contrast, instrument actuators (36b, 36c, 36d, 36e, 36f) are linear system actuators (36b, 36c, 36d, 36e, 36f) configured to translationally drive movement of portions of end effector (<NUM>) and/or shaft assembly (<NUM>) while simultaneously allowing for rotation of shaft assembly (<NUM>) via roll system actuator (36a).

Roll system actuator (36a) in one example includes a drive spool (<NUM>) rigidly connected to puck (38a) (see <FIG>) and a driven spool (<NUM>) rigidly connected to proximal shaft portion (<NUM>) within housing (<NUM>). Drive spool (<NUM>) is mounted to rotate with puck (38a) (see <FIG>) about a common puck axis, whereas driven spool (<NUM>) is mounted to rotate with proximal shaft portion (<NUM>) about the longitudinal axis (<NUM>). A cable (<NUM>) wraps around each of the drive and driven spools (<NUM>, <NUM>), accommodating the differing orientation of the puck axis and longitudinal axis (<NUM>), such that rotating drive spool (<NUM>) via puck (38a) (see <FIG>) urges rotation of driven spool (<NUM>). In turn, shaft assembly (<NUM>), including proximal and distal shaft portions (<NUM>, <NUM>) rotates about longitudinal axis (<NUM>) as indicated by arrow (<NUM>) (see <FIG>), such as by robotically driven actuation of puck (38a) (see <FIG>).

Linear system actuators (36b, 36c, 36d, 36e, 36f) of the present example include a gear-rack mechanism (<NUM>) having a rotatable drive gear (<NUM>), a translatable rack gear (<NUM>), and an idler gear (<NUM>) connected therebetween. Drive gears (<NUM>) are respectively connected to and rigidly project from pucks (38b, 38c, 38d, 38e, 38f) (see <FIG>), whereas each rack gear (<NUM>) is connected to another portion of proximal shaft portion (<NUM>) directing movement of shaft assembly (<NUM>) and/or end effector (<NUM>) as discussed above. Each rack gear (<NUM>) is cylindrical and rigidly connected relative to proximal shaft portion (<NUM>) to rotate therewith. Rack gear (<NUM>) is thereby configured to rotate with shaft assembly (<NUM>) while remaining meshed with idler gear (<NUM>). Rotating respective pucks (38b, 38c, 38d, 38e, 38f) (see <FIG>) thus respectively rotates drive gears (<NUM>) and idler gears (<NUM>) to translate rack gears (<NUM>) as desired.

In the present example, with respect to <FIG> and <FIG>, linear system actuator (36b) has puck (38b) operatively connected to clamp arm (<NUM>) to direct movement of clamp arm (<NUM>) between the open and closed positions according to arrow (<NUM>). Linear system actuators (36c, 36d) have respective pucks (38c, 38d) operatively connected to clamp arm (<NUM>) to direct movement of clamp arm (<NUM>) around blade (<NUM>) in both the clockwise and counterclockwise directions according to arrow (<NUM>). In addition, linear system actuators (36e, 36f) have respective pucks (38e, 38f) operatively connected to articulation bands (<NUM>) to direct movement of articulation section (<NUM>) according to arrows (<NUM>, <NUM>) for deflecting end effector (<NUM>) relative to longitudinal axis (<NUM>). Of course, in other examples, instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) may be alternatively configured with more or less actuators (36a, 36b, 36c, 36d, 36e, 36f) and/or more or less movement as desired. The disclosure is thus not intended to be unnecessarily limited to instrument actuators (36a, 36b, 36c, 36d, 36e, 36f) or particular movements of shaft assembly (<NUM>) and/or end effector (<NUM>) as described in the present example.

In some instances, with respect to <FIG>, it may be desirable to guide deflection of end effector (<NUM>) at least in part according to various properties and/or constraints associated with components passing through articulation section (<NUM>) during use. By way of example, greater variability in such deflection, such as by increased articulation along shaft assembly (<NUM>), may increase strain on one or more flexible components within articulation section (<NUM>). Articulation section (<NUM>) may thus be desirably articulated via links (<NUM>, <NUM>, <NUM>) in one example to accurately and precisely guide movement of flexible components within articulation section (<NUM>) while reducing strain that may otherwise occur through these flexible components, such as acoustic waveguide (<NUM>).

By way of further example, greater variability of deflection along shaft assembly (<NUM>) may incorporate a plurality of articulation sections (<NUM>) with respective links (<NUM>, <NUM>, <NUM>) for guiding any one of a plurality of acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) (see <FIG>) through greater degrees of freedom than acoustic waveguide (<NUM>) of ultrasonic surgical instrument (<NUM>). To this end, shaft assembly (<NUM>) with end effector (<NUM>) is more generally configured to move longitudinally along longitudinal axis (<NUM>), laterally perpendicular to longitudinal axis (<NUM>), and transversely perpendicular to longitudinal axis (<NUM>) as well as rotate end effector (<NUM>) about longitudinal axis (<NUM>) and pivot end effector (<NUM>) along a plane, which may be pitch or yaw depending on the relative position of end effector (<NUM>). While such movement provides five degrees of freedom to end effector (<NUM>) via acoustic waveguide (<NUM>) during use, any one or more of the plurality of acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) (see <FIG>) described below are configured to enable end effector (<NUM>) to pivot through an additional plane for six degrees of freedom. Additional articulation sections (<NUM>) and/or alternative articulations (not shown) are thus configured to guide deflection of end effector (<NUM>) while reducing strain on acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) (see <FIG>). While the following provides additional details with respect to a second example of an ultrasonic surgical instrument (<NUM>) having dual articulation sections (<NUM>, <NUM>) as shown in <FIG>, the disclosure is not intended to be unnecessarily limited to one or more of such articulation sections (<NUM>, <NUM>). Indeed, any alternative articulation section (not shown) may be used alone or in combination for supporting acoustic waveguides having one or more flexible portions, such as acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) (see <FIG>) described below in greater detail. In addition, like numbers below indicate like features described above in greater detail.

<FIG> show a second example of an ultrasonic surgical instrument (<NUM>) having another example of a base assembly (<NUM>) and a distally extending multi-planar shaft assembly (<NUM>) with end effector (<NUM>). Base and shaft assemblies (<NUM>, <NUM>) are similar to base and shaft assemblies (<NUM>, <NUM>) (see <FIG>) discussed above in greater detail, but are collectively configured for multi-planar articulation. More particularly, shaft assembly (<NUM>) includes articulation section (<NUM>) as a proximal articulation section (<NUM>) and further includes a distal articulation section (<NUM>). Base assembly (<NUM>) is thus configured to direct articulation of proximal articulation section (<NUM>) as discussed above with respect to base assembly (<NUM>) (see <FIG>) and also configured to direct articulation of distal articulation section (<NUM>). Such movement of distal articulation section (<NUM>) in one example is performed by an additional instrument actuator (not shown). Alternatively, movement of distal articulation section (<NUM>) in another example is performed by another one of instrument actuators (36a, 36b, 36c, 36d, 36e, 36f). Unless explicitly stated herein, base and shaft assemblies (<NUM>, <NUM>) are otherwise constructed and operable as base and shaft assemblies (<NUM>, <NUM>) (see <FIG>) discussed above in greater detail.

Proximal and distal articulation sections (<NUM>, <NUM>) are similarly constructed in the present example with links (<NUM>, <NUM>, <NUM>) as discussed above. Proximal articulation section (<NUM>) thus articulates through a plane, whereas distal articulation section (<NUM>) articulates through another plane. In the present example, these planes are perpendicular to each other. Given the rotational orientation of shaft assembly (<NUM>) as shown in <FIG>, proximal articulation section (<NUM>) articulates through a pitch plane and distal articulation section (<NUM>) articulates through a yaw plane relative to clamp arm (<NUM>). However, it will be appreciated that such planes change relative to clamp arm (<NUM>) and/or as oriented in <FIG>, such as the disclosure is not intended to be unnecessarily limited to the yaw and pitch planes as shown in the present example. While <FIG> shows one example of dual articulation for each of proximal and distal articulation sections (<NUM>, <NUM>) such that end effector (<NUM>) may be selectively moved according to six degrees of freedom, it will be further appreciated that any desired articulation and combination of respective articulations may be similarly used. Again, the disclosure is not intended to be unnecessarily limited to the particular angles of articulation shown in the yaw and pitch planes of the present example.

<FIG> show distal articulation section (<NUM>) with proximal, distal, and intermediate links (<NUM>, <NUM>, <NUM>), articulation bands (<NUM>), and a distal flexible portion (<NUM>) of a first exemplary multi-flex acoustic waveguide (<NUM>) extending therethrough. Links (<NUM>, <NUM>, <NUM>) collectively define channels (<NUM>) configured to receive articulation bands (<NUM>) such that articulation bands (<NUM>) transversely align links (<NUM>, <NUM>, <NUM>) with a remainder of shaft assembly (<NUM>) as well as provide transverse support of links (<NUM>, <NUM>, <NUM>) along distal articulation section (<NUM>). As discussed above, links (<NUM>, <NUM>, <NUM>) have arcuate grooves (<NUM>) receiving arcuate tongues (<NUM>) along a lateral centerline positioned between articulation bands (<NUM>) such that articulation bands (<NUM>) are transversely offset and on opposing sides of distal flexible portion (<NUM>) thereby maintaining axial position of distal articulation section (<NUM>). Furthermore, each link (<NUM>, <NUM>, <NUM>) defines a link hollow (<NUM>) configured to receive distal flexible portion (<NUM>) and provide distal flexible portion (<NUM>) with sufficient and constant clearance space therealong to remain untouched by any portion of one of links (<NUM>, <NUM>, <NUM>) whether in the straight configuration or any articulated configuration, which is limited to maximum articulated configurations via cooperating distal and proximal stops (<NUM>, <NUM>). To this end, proximal stop (<NUM>) on one link (<NUM>, <NUM>, <NUM>) is configured to engage distal stop (<NUM>) on another adjacent link (<NUM>, <NUM>, <NUM>) to thereby limit collective articulation of distal articulation section (<NUM>) and, in turn, limit strain due to articulation on distal flexible portion (<NUM>) of acoustic waveguide (<NUM>).

With respect to <FIG>, slots (<NUM>) in each link (<NUM>, <NUM>, <NUM>) that collectively define channels (<NUM>) are configured to slidably receive articulation bands (<NUM>) (see <FIG>). Slots (<NUM>) also have drafted openings (<NUM>) to inhibit kinking of articulation bands (<NUM>) (see <FIG>) during use. Additional control members (not shown), such as additional drivers (not shown), are also connected between end effector (<NUM>) (see <FIG>) and base assembly (<NUM>) (see <FIG>) and thus extend through distal articulation section (<NUM>) in the present example. These additional control members (not shown) are received through arcuate tongues and grooves (<NUM>, <NUM>) along lateral centerline to inhibit changing lengths associated with articulation of distal articulation section (<NUM>). More particularly, a pair of passageways (<NUM>) longitudinally extend through each link (<NUM>, <NUM>, <NUM>) in alignment with arcuate tongues and grooves (<NUM>, <NUM>) to collectively define a pair of additional channels (<NUM>) configured to guide control members (not shown) through distal articulation section (<NUM>). Each passageway (<NUM>) also has a widened groove opening (<NUM>) and a widened tongue opening (<NUM>) as respectively applicable to arcuate groove and tongues (<NUM>, <NUM>) of links (<NUM>, <NUM>, <NUM>). Each of widened groove and tongue opening (<NUM>, <NUM>) is drafted to inhibit kinking of additional control members (not shown) while articulating distal articulation section (<NUM>) as described herein. In one example, links (<NUM>, <NUM>, <NUM>) may further include a material sleeve (not shown) or material coating (not shown) configured to further inhibit kinking and/or inhibit damage to flexible portion (<NUM>) of acoustic waveguide (<NUM>) in case of incidental contact.

<FIG> show distal link (<NUM>) in greater detail in one example having a distal link body (<NUM>) with proximally extending arcuate tongue (<NUM>) and proximally extending arcuate groove (<NUM>) with passageways (<NUM>). Distal link body (<NUM>) further includes distally extending coupling members (<NUM>) configured to be received within another portion of shaft assembly (<NUM>) (see <FIG>) for rigidly connecting therewith. Notches (<NUM>) and pins (<NUM>) configured to connect to articulation bands (<NUM>) (see <FIG>) are also shown angularly between arcuate tongue and groove (<NUM>, <NUM>), whereas distal stops (<NUM>) are respectively positioned about arcuate tongue and groove (<NUM>, <NUM>). Of course, distal link (<NUM>) may vary as desired for incorporating distal articulation section (<NUM>) (see <FIG>) into shaft assembly (<NUM>) (see <FIG>) such that the disclosure is not intended to be unnecessarily limited to the particular distal link (<NUM>) shown in the present example.

<FIG> show intermediate link (<NUM>) in greater detail in one example having an intermediate link body (<NUM>) with proximally and distally extending arcuate tongues (<NUM>) and proximally and distally extending arcuate grooves (<NUM>) with passageways (<NUM>). Distal stops (<NUM>) are respectively positioned about distally facing arcuate tongue and groove (<NUM>, <NUM>), whereas proximal stops (<NUM>) are respectively positioned about proximally facing arcuate tongue and groove (<NUM>, <NUM>). Of course, intermediate link (<NUM>) may vary as desired for incorporating distal articulation section (<NUM>) (see <FIG>) into shaft assembly (<NUM>) (see <FIG>) such that the disclosure is not intended to be unnecessarily limited to the particular intermediate link (<NUM>) shown in the present example.

<FIG> show proximal link (<NUM>) in greater detail in one example having a proximal link body (<NUM>) with distally extending arcuate tongue (<NUM>) and distally extending arcuate groove (<NUM>) with passageways (<NUM>). Proximal link body (<NUM>) further includes proximally extending coupling members (<NUM>) configured to be received within another portion of shaft assembly (<NUM>) (see <FIG>) for rigidly connecting therewith. Slots (<NUM>) are configured to receive articulation bands (<NUM>) (see <FIG>) and shown angularly between arcuate tongue and groove (<NUM>, <NUM>), whereas proximal stops (<NUM>) are respectively positioned about arcuate tongue and groove (<NUM>, <NUM>). Of course, proximal link (<NUM>) may vary as desired for incorporating distal articulation section (<NUM>) (see <FIG>) into shaft assembly (<NUM>) (see <FIG>) such that the disclosure is not intended to be unnecessarily limited to the particular proximal link (<NUM>) shown in the present example.

In use, referring back to <FIG>, the operator selectively directs proximal and distal articulation sections (<NUM>, <NUM>) in order to deflect end effector (<NUM>) relative to longitudinal axis (<NUM>). In one example, proximal articulation section (<NUM>) articulates in order to deflect a distal remainder of shaft assembly (<NUM>) with end effector (<NUM>) through the pitch plane relative to axis (<NUM>) and then distal articulation section (<NUM>) articulates in order to deflect a further distal remainder of shaft assembly (<NUM>) with end effector (<NUM>) through the yaw plane relative to axis (<NUM>). In another example, distal articulation section (<NUM>) articulates in order to deflect the further distal remainder of shaft assembly (<NUM>) with end effector (<NUM>) through the yaw plane and then proximal articulation section (<NUM>) articulates in order to deflect a distal remainder of shaft assembly (<NUM>) with end effector (<NUM>) through the pitch plane. In still another example, proximal and distal articulation sections (<NUM>, <NUM>) simultaneously articulate in order to deflect remainders of shaft assembly (<NUM>) and end effector through the pitch and yaw planes respectively. Alternatively, either one of proximal or distal articulation sections (<NUM>, <NUM>) are articulated without articulating the remaining of the proximal or distal articulation sections (<NUM>, <NUM>). In any case, end effector (<NUM>) is thereby configured to deflect through at least two distinct planes via one or more articulation sections (<NUM>, <NUM>).

While the present example provides two distinct planes through which to move end effector (<NUM>) via two respective articulation sections (<NUM>, <NUM>), an alternative articulation section may be configured to provide articulation in at least two distinct planes in a series of joints at discrete longitudinal positions, similar to shaft assembly (<NUM>) with articulation sections (<NUM>, <NUM>), or in a single joint capable of articulating through at least two planes in one discrete longitudinal position. The disclosure is thus not intended to be unnecessarily limited to multiple articulation sections as shown in the present example for multi-planar articulation as will be appreciated in view of various multi-flex acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) discussed below in greater detail.

While movement of end effector (<NUM>) in six degrees of freedom may increase access to an anatomy of the patient during a surgical procedure for improved patient outcomes, such flexibility tends to strain components, particularly those components configured to communicate ultrasonic vibrations from transducer assembly (<NUM>) to ultrasonic blade (<NUM>). By way of example, acoustic waveguide (<NUM>) of ultrasonic surgical instrument (<NUM>) in <FIG> is configured to flex at one such flexible portion (<NUM>) within articulation section (<NUM>) through one plane, but further flexing through another plane would overly strain acoustic waveguide (<NUM>) resulting in damage and ultimately failure of acoustic waveguide (<NUM>). Such damage and failure of acoustic waveguide (<NUM>) tends to occur, because forced flexing of acoustic waveguide (<NUM>) generates stress concentrations in one or more locations along acoustic waveguide (<NUM>). In turn, these locations of stress concentrations within acoustic waveguide (<NUM>) continue to carry the ultrasonic vibrations, resulting in damage, fracture, and failure of acoustic waveguide (<NUM>) in use.

Multi-flex acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) discussed below with respect to <FIG> are thus configured to provide flexing in more than one plane with increased durability. More particularly, multi-flex acoustic waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) have one or more structural formations configured to communicate ultrasonic vibrations while being flexed in one or more of a variety of available planes of deflection. While shaft assembly (<NUM>) (see <FIG>) discussed above incorporates acoustic waveguide (<NUM>), it will be appreciated that any other waveguides (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) may also be incorporated into shaft assembly (<NUM>), such that the disclosure is not intended to be unnecessarily limited to use with shaft assembly (<NUM>) (see <FIG>) discussed above. Like numbers below indicate like features described above in greater detail.

<FIG> show the first exemplary multi-flex acoustic waveguide (<NUM>) having proximal flexible portion (<NUM>) and distal flexible portion (<NUM>) configured to respectively flex in a pitch direction through the pitch plane and in a yaw direction through the yaw plane. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having proximal and distal flexible portions (<NUM>, <NUM>) is thus configured to flex in the pitch and yaw directions to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through the pitch and yaw planes for multi-planar deflection. In the present example of proximal waveguide body portion (<NUM>), articulation body portion (<NUM>), distal waveguide body portion (<NUM>), and ultrasonic blade (<NUM>) have a single, unitary construction, although multi-flex acoustic waveguide (<NUM>) may be alternatively constructed with one or more connected structures. The disclosure is thus not intended to be unnecessarily limited to single, unitary construction of multi-flex acoustic waveguide (<NUM>) shown in the present example.

More particularly, proximal flexible portion (<NUM>) includes a flexible proximal pitch ribbon (<NUM>), whereas distal flexible portion (<NUM>) includes a flexible distal yaw ribbon (<NUM>). Articulation body portion (<NUM>) also includes an intermediate waveguide body portion (<NUM>), extending between and in direct connection with flexible proximal pitch ribbon (<NUM>) and flexible distal yaw ribbon (<NUM>). Bosses (<NUM>) are positioned on waveguide body portions (<NUM>, <NUM>, <NUM>) and respectively spaced apart from each other so as to coincide with and, more particularly, be centered on respective acoustic nodes along multi-flex acoustic waveguide (<NUM>). Similarly, flexible proximal pitch ribbon (<NUM>) is positioned and centered on an acoustic antinode of multi-flex acoustic waveguide (<NUM>), while flexible distal yaw ribbon (<NUM>) is also positioned and centered on another acoustic antinode of multi-flex acoustic waveguide (<NUM>).

<FIG> show multi-flex acoustic waveguide (<NUM>) with each of flexible proximal pitch ribbon (<NUM>) and flexible distal yaw ribbon (<NUM>) in a linear form such that multi-flex acoustic waveguide (<NUM>) has a straight contour. Each ribbon (<NUM>, <NUM>) is thereby configured to communicate ultrasonic vibrations in the straight contour longitudinally toward ultrasonic blade (<NUM>) during use. Selectively bending flexible proximal pitch ribbon (<NUM>) relative to longitudinal axis (<NUM>) away from longitudinal axis (<NUM>) results in one of any available arcuate contours for flexible proximal pitch ribbon (<NUM>). Alternatively or in addition, selectively bending flexible distal yaw ribbon (<NUM>) relative an intermediate axis (<NUM>) defined by intermediate waveguide body portion (<NUM>) away from intermediate axis (<NUM>) results in one of any available arcuate contours for flexible distal yaw ribbon (<NUM>). In one example, articulation body portion (<NUM>) extends along the arcuate contour of only one of flexible proximal pitch ribbon (<NUM>) or flexible distal yaw ribbon (<NUM>) such that ultrasonic blade (<NUM>) deflects through one of two available planes along a blade axis (<NUM>). In another example, articulation body portion (<NUM>) extends along the arcuate contour of both flexible proximal pitch ribbon (<NUM>) and flexible distal yaw ribbon (<NUM>) for a dual arcuate contour such that ultrasonic blade (<NUM>) deflects through each of two available planes along blade axis (<NUM>). While the present example has ribbons (<NUM>, <NUM>) angularly oriented perpendicular to each to each other, one or both ribbons (<NUM>, <NUM>) may have any relative angular orientation and are not intended to be limited to the angular orientation as shown and described herein.

<FIG> shows a second exemplary multi-flex acoustic waveguide (<NUM>) having a proximal flexible portion (458a) and a distal flexible portion (458b) configured to respectively flex in a yaw direction through a proximal yaw plane and again in a yaw direction through a distal yaw plane. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having proximal and distal flexible portions (458a, 458b) is thus configured to flex in the yaw direction at multiple locations to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through multiple yaw planes for multi-planar deflection. In the present example proximal waveguide body portion (<NUM>), articulation body portion (<NUM>), distal waveguide body portion (<NUM>), and ultrasonic blade (<NUM>) have a single, unitary construction, although multi-flex acoustic waveguide (<NUM>) may be alternatively constructed with one or more connected structures. The disclosure is thus not intended to be unnecessarily limited to single, unitary construction of multi-flex acoustic waveguide (<NUM>) shown in the present example.

More particularly, proximal flexible portion (458a) includes a flexible proximal yaw ribbon (<NUM>), whereas distal flexible portion (458b) includes a flexible distal yaw ribbon (<NUM>). Articulation body portion (<NUM>) also includes an intermediate waveguide body portion (<NUM>), extending between and in direct connection with flexible proximal yaw ribbon (<NUM>) and flexible distal yaw ribbon (<NUM>). Bosses (not shown) may be positioned on waveguide body portions (<NUM>, <NUM>, <NUM>) and respectively spaced apart from each other so as to coincide with and, more particularly, be centered on respective acoustic nodes along multi-flex acoustic waveguide (<NUM>). Similarly, flexible proximal yaw ribbon (<NUM>) is positioned and centered on an acoustic antinode of multi-flex acoustic waveguide (<NUM>), while flexible distal yaw ribbon (<NUM>) is also positioned and centered on another acoustic antinode of multi-flex acoustic waveguide (<NUM>).

Each ribbon (<NUM>, <NUM>) is configured to communicate ultrasonic vibrations in a straight contour longitudinally toward ultrasonic blade (<NUM>) during use. Selectively bending flexible proximal yaw ribbon (<NUM>) relative to longitudinal axis (<NUM>) away from longitudinal axis (<NUM>) results in one of any available arcuate contours for flexible proximal yaw ribbon (<NUM>). Alternatively or in addition, selectively bending flexible distal yaw ribbon (<NUM>) relative an intermediate axis (<NUM>) defined by intermediate waveguide body portion (<NUM>) away from intermediate axis (<NUM>) results in one of any available arcuate contours for flexible distal yaw ribbon (<NUM>). In one example, articulation body portion (<NUM>) extends along the arcuate contour of only one of flexible proximal yaw ribbon (<NUM>) or flexible distal yaw ribbon (<NUM>) such that ultrasonic blade (<NUM>) deflects through one of two available planes along a blade axis (<NUM>). In another example, articulation body portion (<NUM>) extends along the arcuate contour of both flexible proximal yaw ribbon (<NUM>) and flexible distal yaw ribbon (<NUM>) for a dual arcuate contour such that ultrasonic blade (<NUM>) deflects through each of two available planes along blade axis (<NUM>) and as shown in <FIG>. While the present example has ribbons (<NUM>, <NUM>) in the same angular orientation, one or both ribbons (<NUM>, <NUM>) may have any relative angular orientation and are not intended to be limited to the angular orientation as shown and described herein.

<FIG> show a third exemplary multi-flex acoustic waveguide (<NUM>) having a flexible portion (<NUM>) configured to flex in a full <NUM>-degree range of radial directions through a respective full <NUM>-degree range of radial planes. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having flexible portion (<NUM>) is thus configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection. In the present example, proximal waveguide body portion (<NUM>), articulation body portion (<NUM>), distal waveguide body portion (<NUM>), and ultrasonic blade (<NUM>) have a single, unitary construction, although multi-flex acoustic waveguide (<NUM>) may be alternatively constructed with one or more connected structures. The disclosure is thus not intended to be unnecessarily limited to single, unitary construction of multi-flex acoustic waveguide (<NUM>) shown in the present example.

More particularly, as shown in <FIG>, flexible portion (<NUM>) includes a first example of a flexible wire (<NUM>) configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection. Flexible wire (<NUM>) is elongated and cylindrical defining a wire cross-sectional radius (r). Bosses (<NUM>) are positioned on waveguide body portions (<NUM>, <NUM>) and are respectively spaced apart from each other so as to coincide with and, more particularly, be centered on respective acoustic nodes along multi-flex acoustic waveguide (<NUM>). Similarly, flexible wire (<NUM>) is positioned and centered on an acoustic antinode of multi-flex acoustic waveguide (<NUM>). Each proximal and distal waveguide body portion (<NUM>, <NUM>) is more rigid than flexible wire (<NUM>) and has a conical taper (<NUM>) narrowing toward flexible wire (<NUM>). Between conical tapers (<NUM>) and bosses (<NUM>), proximal and distal waveguide body portions (<NUM>, <NUM>) each define a waveguide body radius. In the present example, waveguide body radius is larger than wire cross-sectional radius (r).

<FIG> shows multi-flex acoustic waveguide (<NUM>) with flexible wire (<NUM>) in a linear form such that multi-flex acoustic waveguide (<NUM>) has a straight contour. Flexible wire (<NUM>) is thereby configured to communicate ultrasonic vibrations in the straight contour longitudinally toward ultrasonic blade (<NUM>) during use. Selectively bending flexible wire (<NUM>) relative to longitudinal axis (<NUM>) away from longitudinal axis (<NUM>) results in one of any available arcuate contours for flexible wire (<NUM>) with ultrasonic blade (<NUM>) deflecting through one of any available radial plane along a blade axis (<NUM>) and about a bend radius (R). One example of such bend radius (R) is shown in <FIG>. With the arcuate contour, flexible wire (<NUM>) is configured to uncouple a longitudinal vibrational component of the ultrasonic vibration from a transverse vibrational component of the ultrasonic vibration to thereby communicate the ultrasonic vibration about the bent flexible wire (<NUM>) without damaging flexible wire (<NUM>) or substantially degrading the ultrasonic vibration during use.

To this end, acoustic waveguide (<NUM>) has a set of predetermined properties to uncouple the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration during use. In the present example, the predetermined properties include wire cross-sectional radius (r) and bend radius (R) discussed above in addition to a plurality of wire material properties, including an elastic modulus (E) of flexible wire (<NUM>), a yield strength (σy) of flexible wire (<NUM>), a natural frequency (f) of flexible wire (<NUM>), as well as a constant, the speed of sound (c). Given that bend radius (R) may vary, predetermined properties further include a first condition, a second condition, and a third condition that accommodate a range of available bend radii (R) while still effectively uncoupling the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration during use. As shown in one example, these conditions are as follows. <MAT> <MAT> <MAT>.

While the particular material, sizing, and bend of flexible wire (<NUM>) may vary to achieve uncoupling of the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration, in one example the material is a nitinol material. In another example, the material of flexible wire (<NUM>) is a titanium material. The invention is thus not intended to be unnecessarily limited to the particular material, sizing, and bend of flexible wire (<NUM>) as shown and described herein.

With respect to <FIG>, flexible wire (<NUM>) has one bend about an acoustic antinode with bend radius (R). Alternatively or in addition, an alternative flexible wire (not shown) may have an additional bend (not shown) about another antinode such that flexible wire (not shown) is configured to bend at two or more positions during use, similar to dual flexible portions (<NUM>, <NUM>, 458a, 458b) (see <FIG>) associated with acoustic waveguides (<NUM>, <NUM>) (see <FIG>) discussed above in greater detail. Such an alternative flexible wire (not shown) may be offset from flexible wire (<NUM>) with an intermediate waveguide body portion (not shown) therebetween similar to acoustic waveguides (<NUM>, <NUM>) (see <FIG>) or without intermediate waveguide body portion (not shown) such that alternative flexible wire (not shown) and flexible wire (<NUM>) are essentially continuous therealong. The disclosure is thus not intended to be unnecessarily limited to the arrangement of one flexible wire (<NUM>) as shown in the present example.

<FIG> show a fourth exemplary multi-flex acoustic waveguide (<NUM>) having a flexible portion (<NUM>) configured to flex in a full <NUM>-degree range of radial directions through a respective full <NUM>-degree range of radial planes. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having flexible portion (<NUM>) is thus configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection.

More particularly, flexible portion (<NUM>) includes a second example of a flexible wire (<NUM>) configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection. In this respect, acoustic waveguide (<NUM>) is similar to acoustic waveguide (<NUM>) (see <FIG>), but, rather than being unitarily constructed, acoustic waveguide (<NUM>) is assembled via several discrete components. Flexible wire (<NUM>) is like flexible wire (<NUM>) (see <FIG>) discussed above in other respects unless otherwise stated below.

As shown in the present example, flexible portion (<NUM>) further includes a distal wire end portion (<NUM>) opposite from a proximal wire end portion (<NUM>) with flexible wire (<NUM>) extending therebetween. Distal and proximal wire end portions (<NUM>, <NUM>) each have a conical taper (<NUM>) narrowing toward flexible wire (<NUM>). Extending opposite from respective conical tapers (<NUM>), distal end proximal wire end portions (<NUM>, <NUM>) further respectively include a distal coupling (<NUM>) configured to connect to distal waveguide body portion (<NUM>) and a proximal coupling (<NUM>) configured to connect to proximal waveguide body portion (<NUM>). As shown in the present example, distal coupling (<NUM>) includes a distal threaded stud (<NUM>) distally extending from distal wire end portion (<NUM>) and a distal threaded bore (<NUM>) in distal waveguide body portion (<NUM>). Distal threaded stud (<NUM>) mechanically and acoustically couples into distal threaded bore (<NUM>) to connect flexible wire (<NUM>) to distal waveguide body portion (<NUM>). Similarly, proximal coupling (<NUM>) includes a proximal threaded stud (<NUM>) proximally extending from proximal wire end portion (<NUM>) and a proximal threaded bore (<NUM>) in proximal waveguide body portion (<NUM>). Proximal threaded stud (<NUM>) mechanically and acoustically couples into proximal threaded bore (<NUM>) to connect flexible wire (<NUM>) to proximal waveguide body portion (<NUM>).

With acoustic waveguide (<NUM>) assembled via several discrete components, one or more of proximal waveguide body potion (<NUM>), distal waveguide body portion (<NUM>), and articulation body portion (<NUM>) may be formed from differing materials. By way of example, proximal waveguide body potion (<NUM>) is formed from one of titanium material, aluminum, material, or nitinol material. In addition, distal waveguide body potion (<NUM>), which includes ultrasonic blade (<NUM>), is formed from one of titanium material or nitinol material. Similarly, articulation body portion (<NUM>) is formed from one of titanium material or nitinol material. Any combination of such materials may be incorporated into acoustic waveguide (<NUM>) and thus configured to uncouple the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration based on the set of predetermined properties discussed above in greater detail. While the present example incorporates threads into acoustic waveguide (<NUM>) for connecting various components of differing materials, such connections may additionally or alternatively include swaging, welding, temperature fits, and/or shape memory fits. The disclosure is thus not intended to be unnecessarily limited to the particular threaded couplings (<NUM>, <NUM>) shown and described in the present example.

<FIG> show a fifth exemplary multi-flex acoustic waveguide (<NUM>) having a flexible portion (<NUM>) configured to flex in a full <NUM>-degree range of radial directions through a respective full <NUM> degree range of radial planes. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having flexible portion (<NUM>) is thus configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection.

More particularly, flexible portion (<NUM>) includes a third example of a flexible wire (<NUM>) configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection. In this respect, acoustic waveguide (<NUM>) is similar to acoustic waveguide (<NUM>) (see <FIG>), but, rather than being unitarily constructed, acoustic waveguide (<NUM>) is assembled via several discrete components. Flexible wire (<NUM>) is like flexible wire (<NUM>) (see <FIG>) discussed above in other respects unless otherwise stated below.

As shown in the present example, flexible portion (<NUM>) further includes a distal wire end portion (<NUM>) opposite from a proximal wire end portion (<NUM>) with flexible wire (<NUM>) extending therebetween. Distal and proximal wire end portions (<NUM>, <NUM>) respectively include a distal coupling (<NUM>) configured to connect to distal waveguide body portion (<NUM>) and a proximal coupling (<NUM>) configured to connect to proximal waveguide body portion (<NUM>). As shown in the present example, distal coupling (<NUM>) includes distal wire end portion (<NUM>) and a distal bore (<NUM>) in distal waveguide body portion (<NUM>). Distal wire end portion (<NUM>) is swaged into distal bore (<NUM>) to thereby mechanically and acoustically couple flexible wire (<NUM>) to distal waveguide body portion (<NUM>). Similarly, proximal coupling (<NUM>) includes proximal wire end portion (<NUM>) and a proximal bore (<NUM>) in proximal waveguide body portion (<NUM>). Proximal wire end portion (<NUM>) is swaged into proximal bore (<NUM>) to thereby mechanically and acoustically couple flexible wire (<NUM>) to proximal waveguide body portion (<NUM>).

With acoustic waveguide (<NUM>) assembled via several discrete components, one or more of proximal waveguide body potion (<NUM>), distal waveguide body portion (<NUM>), and articulation body portion (<NUM>) may be formed from differing materials. By way of example, proximal waveguide body potion (<NUM>) is formed from one of titanium material, aluminum, material, or nitinol material. In addition, distal waveguide body potion (<NUM>), which includes ultrasonic blade (<NUM>), is formed from one of titanium material or nitinol material. Similarly, articulation body portion (<NUM>) is formed from one of titanium material or nitinol material. Any combination of such materials may be incorporated into acoustic waveguide (<NUM>) and thus configured to uncouple the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration based on the set of predetermined properties discussed above in greater detail. While the present example swages portions of acoustic waveguide (<NUM>) together for connecting various components of differing materials, such connections may additionally or alternatively include threading, welding, temperature fits, and/or shape memory fits. The disclosure is thus not intended to be unnecessarily limited to the particular swaging shown and described in the present example.

<FIG> show a sixth exemplary multi-flex acoustic waveguide (<NUM>) having a flexible portion (<NUM>) configured to flex in a full <NUM>-degree range of radial directions through a respective full <NUM>-degree range of radial planes. Acoustic waveguide (<NUM>) of the present example more particularly includes a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>), a distal waveguide body portion (<NUM>) distally extending to an ultrasonic blade (<NUM>), and an articulation body portion (<NUM>) longitudinally extending therebetween. Articulation body portion (<NUM>) having flexible portion (<NUM>) is thus configured to flex in any radial direction about longitudinal axis (<NUM>) to thereby deflect ultrasonic blade (<NUM>) relative to longitudinal axis (<NUM>) through any respective radial plane for multi-planar deflection. In the present example, proximal waveguide body portion (<NUM>), articulation body portion (<NUM>), distal waveguide body portion (<NUM>), and ultrasonic blade (<NUM>) have a single, unitary construction, although multi-flex acoustic waveguide (<NUM>) may be alternatively constructed with one or more connected structures. The disclosure is thus not intended to be unnecessarily limited to single, unitary construction of multi-flex acoustic waveguide (<NUM>) shown in the present example.

More particularly, flexible portion (<NUM>) includes an elongate flexible wire (<NUM>) extending essentially an entire length of articulation body portion (<NUM>) such that proximal waveguide body portion (<NUM>) is a proximal portion of acoustic waveguide (<NUM>) configured to be received within transducer assembly (<NUM>) and distal waveguide body portion (<NUM>) is generlly ultrasonic blade (<NUM>). A majority of acoustic waveguide (<NUM>) is thus elongate flexible wire (<NUM>), which extends along a plurality of acoustic nodes (<NUM>) and a plurality of acoustic antinodes (<NUM>). Thus, elongate flexible wire (<NUM>) is configured to flex in any radial direction about longitudinal axis (<NUM>) as well as further flex in any radial direction about axes (<NUM>), which are positioned and aligned at acoustic nodes (<NUM>), respectively. Furthermore, elongate flexible wire (<NUM>) of the present example includes a plurality of flexible wire portions (<NUM>) respectively centered at acoustic antinodes (<NUM>) of multi-flex acoustic waveguide (<NUM>). Flexible wire portions (<NUM>) and intermediate wire portions are thus continuous to define elongate flexible wire (<NUM>) in the present example.

<FIG> shows multi-flex acoustic waveguide (<NUM>) with elongate flexible wire (<NUM>) in a linear form such that multi-flex acoustic waveguide (<NUM>) has a straight contour. Flexible wire (<NUM>) is thereby configured to communicate ultrasonic vibrations in the straight contour longitudinally toward ultrasonic blade (<NUM>) during use. Selectively bending flexible wire (<NUM>) at any flexible wire portion (<NUM>) relative to axes (<NUM>, <NUM>) results in one of any available arcuate contours for elongate flexible wire (<NUM>) with ultrasonic blade (<NUM>) deflecting through one of any available radial planes along a blade axis (<NUM>). With the arcuate contour shown in <FIG>, elongate flexible wire (<NUM>) is configured to uncouple a longitudinal vibrational component of the ultrasonic vibration from a transverse vibrational component of the ultrasonic vibration to thereby communicate the ultrasonic vibration about the bent flexible wire (<NUM>) without damaging flexible wire (<NUM>) or substantially degrading the ultrasonic vibration during use. Such vibrational uncoupling is based on the set of predetermined properties discussed above in greater detail.

While the particular material, sizing, and bend of flexible wire (<NUM>) may vary to achieve uncoupling of the longitudinal vibrational component of the ultrasonic vibration from the transverse vibrational component of the ultrasonic vibration, in one example the material is a nitinol material. In another example, the material of flexible wire (<NUM>) is a titanium material. In any case, the invention is thus not intended to be unnecessarily limited to the particular material, sizing, and bend of flexible wire (<NUM>) as shown and described herein.

With respect to <FIG> discussed above in greater detail, clamp arm (<NUM>) is configured to rotate about blade (<NUM>) and also relative to shaft assembly (<NUM>) as indicated by arrow (<NUM>). In one example, clamp arm (<NUM>) selectively rotates in the clockwise or counterclockwise directions around blade (<NUM>) such that the operator selectively fixes clamp arm (<NUM>) angularly about blade (<NUM>) to thereby clamp tissue between blade (<NUM>) and clamp arm (<NUM>) with increased access to the tissue. While clamping between blade (<NUM>) and clamp arm (<NUM>), the operator selectively activates blade (<NUM>) with ultrasonic vibrations and, in one example, seals the tissue clamped therebetween. As shown in the present example, blade (<NUM>) has a blade body (<NUM>) longitudinally extending to a hemispherical distal end tip (<NUM>). Blade body (<NUM>) and hemispherical distal end tip (<NUM>) are generally rounded smooth and free of edges such that blade (<NUM>) is axisymmetric and has a full, circular circumferential sealing profile angularly about an entirety of longitudinal axis (<NUM>). This full, circular circumferential sealing profile represents engagement between rounded smooth surfaces of blade (<NUM>) and clamp pad (<NUM>) such that tissue sealing may occur around an entirety of blade (<NUM>) with clamp pad (<NUM>) clamping tissue thereagainst.

In some instances, it may be desirable to incorporate backcutting functionality into blade (<NUM>) while retaining a majority of the circumferential sealing profile about blade (<NUM>) for sealing tissue against clamp pad (<NUM>). Various examples of ultrasonic blades (<NUM>, <NUM>) with backcutting edges (<NUM>, <NUM>) for providing such backcutting functionality to the operator are described below in greater detail with respect to <FIG>. While backcutting edges (<NUM>, <NUM>) may be incorporated into blade (<NUM>) (see <FIG>), the disclosure is not intended to be unnecessarily limited to including backcutting functionality. Moreover, it will be appreciated that alternative backcutting edges (not shown) may also have a circumferential sealing profile about a majority of a circumferential blade profile such that the disclosure is also not intended to be limited to the particular backcutting edges (<NUM>, <NUM>) shown and described herein.

<FIG> show a first example of a circumferential blade profile of (<NUM>) of an ultrasonic blade (<NUM>) with a first backcutting edge (<NUM>) configured to backcut tissue about a minority of circumferential blade profile (<NUM>) and further configured to seal tissue about a majority of circumferential blade profile (<NUM>). Blade (<NUM>) of the present example more particularly includes a blade body (<NUM>) distally extending to a partially hemispherical distal end tip (<NUM>). A pair of laterally, longitudinally, and transversely swept grooves (<NUM>) extend through partially hemispherical distal end tip (<NUM>) as well as a portion of blade body (<NUM>) to define backcutting edge (<NUM>) along blade (<NUM>). As shown in the present example, a majority of a longitudinal length of backcutting edge (<NUM>) is positioned on partially hemispherical distal end tip (<NUM>) rather than blade body (<NUM>). More particularly, all of the longitudinal length of backcutting edge (<NUM>) is positioned on partially hemispherical distal end tip (<NUM>) in the present example such that no portion of backcutting edge (<NUM>) is positioned on blade body (<NUM>) despite some proximal portion of swept grooves (<NUM>) being on blade body (<NUM>).

As more particularly shown in <FIG>, backcutting edge (<NUM>) longitudinally extends through a transversely extending plane also in alignment with a central blade axis (<NUM>). Swept grooves (<NUM>) are thus laterally symmetric about this transversely extending plane. Circumferential blade profile (<NUM>) of the present example is circular about an entirety of central blade axis (<NUM>) such that clamp pad (<NUM>) extends as a tangent about blade (<NUM>) in any angular position about blade (<NUM>) but for portions of clamp pad (<NUM>) adjacent to swept grooves (<NUM>), thereby defining a circumferential sealing profile (<NUM>). Circumferential sealing profile (<NUM>) is thus arcuate and angularly surrounds a majority of central blade axis (<NUM>), such as greater than <NUM> degrees, without surrounding portions that include swept grooves (<NUM>) and backcutting edge (<NUM>). Circumferential sealing profile (<NUM>) thereby represents the rounded surfaces along partially hemispherical distal end tip (<NUM>) configured for sealing tissue against clamp pad (<NUM>). It will be appreciated that backcutting edge (<NUM>) and swept grooves (<NUM>) may vary while still providing circumferential sealing profile (<NUM>) about the majority of central blade axis (<NUM>). The disclosure is thus not intended to be limited to the particular backcutting edge (<NUM>) and swept grooves (<NUM>) shown in the present example.

In use for sealing tissue, the operator selectively rotates clamp arm (<NUM>) relative to blade (<NUM>) to position clamp pad (<NUM>) in any desirable angular position radially inline with circumferential sealing profile (<NUM>). In turn, tissue is received between clamp pad (<NUM>) and blade (<NUM>) against circumferential sealing profile (<NUM>), and clamp arm (<NUM>) pivots from the open position to the closed position for clamping tissue against blade (<NUM>). The operator selectively actives blade (<NUM>) with ultrasonic vibrations in order to seal tissue clamped between clamp pad (<NUM>) and clamp arm (<NUM>). In the event that the operator desires to selectively backcut tissue, clamp arm (<NUM>) is positioned away from backcutting edge (<NUM>) such that backcutting edge (<NUM>) is relatively exposed. The operator then directly engages tissue with backcutting edge (<NUM>) for backcutting the tissue as desired.

In one example, clamp arm (<NUM>) is further configured to only radially align with the circumferential sealing profile (<NUM>) in order to inhibit the operator from inadvertently moving clamp pad (<NUM>) toward direct engagement with backcutting edge (<NUM>). Clamp arm (<NUM>) may have mechanical stops (not shown) and/or associated software configured to inhibit such rotation. Of course, the disclosure is not intended to be unnecessarily limited to include such alignment constraints and, in some examples, clamp arm (<NUM>) is free to move to any angular position about blade (<NUM>).

<FIG> show a third example of a circumferential blade profile of (<NUM>) of an ultrasonic blade (<NUM>) with a second backcutting edge (<NUM>) configured to backcut tissue about a minority of circumferential blade profile (<NUM>) and further configured to seal tissue about a majority of circumferential blade profile (<NUM>). Blade (<NUM>) of the present example more particularly includes a blade body (<NUM>) distally extending to partially hemispherical distal end tip (<NUM>). A pair of laterally, longitudinally, and transversely swept grooves (<NUM>) extend through partially hemispherical distal end tip (<NUM>). In addition, a pair of laterally, longitudinally, and transversely swept grooves (<NUM>) extend along blade body (<NUM>). Swept grooves (<NUM>) and grooves (<NUM>) collectively define backcutting edge (<NUM>) along blade (<NUM>). As shown in the present example, a majority of a longitudinal length of backcutting edge (<NUM>) is positioned on blade body (<NUM>) such that backcutting edge (<NUM>) extends along majority of a length of blade (<NUM>).

As more particularly shown in <FIG>, backcutting edge (<NUM>) longitudinally extends through a transversely extending plane also in alignment with a central blade axis (<NUM>). Swept grooves (<NUM>, <NUM>) are thus laterally symmetric about this transversely extending plane. Circumferential blade profile (<NUM>) of the present example is circular about an angular majority of central blade axis (<NUM>) such that clamp pad (<NUM>) extends as a tangent about blade (<NUM>) in this angular majority about blade (<NUM>) but for portions of clamp pad (<NUM>) adjacent to swept grooves (<NUM>, <NUM>), thereby defining a circumferential sealing profile (<NUM>). Circumferential sealing profile (<NUM>) is thus arcuate and angularly surrounds a majority of central blade axis (<NUM>), such as greater than <NUM> degrees, without surrounding portions that include swept grooves (<NUM>, <NUM>) and backcutting edge (<NUM>). Circumferential sealing profile (<NUM>) thereby represents the rounded surfaces along partially hemispherical distal end tip (<NUM>) configured for sealing tissue against clamp pad (<NUM>). It will be appreciated that backcutting edge (<NUM>) and swept grooves (<NUM>, <NUM>) may vary while still providing circumferential sealing profile (<NUM>) about the majority of central blade axis (<NUM>). The disclosure is thus not intended to be limited to the particular backcutting edge (<NUM>) and swept grooves (<NUM>, <NUM>) shown in the present example.

With respect to <FIG>, in one example, the distal tip of blade (<NUM>) is positioned to align in a predetermined alignment with a distal tip of clamp arm (<NUM>) in the straight configuration as shown in <FIG> and <FIG>. More particularly, such predetermined alignment positions the distal tip of blade (<NUM>) longitudinally flush with distal tip of clamp arm (<NUM>) in the closed position so that the distal tips of blade (<NUM>) and clamp arm (<NUM>) are positioned in a common plane perpendicular to an axis defined by blade (<NUM>). As articulation section (<NUM>) articulates from the straight configuration toward the articulated configuration as shown in <FIG> and <FIG>, articulation section (<NUM>) essentially elongates as the radius of curvature along articulation section (<NUM>) increases. In turn, blade (<NUM>) moves proximally relative to clamp arm (<NUM>) such that the distal tip of blade (<NUM>) and the distal tip of clamp arm (<NUM>) are no longer longitudinally aligned in the predetermined alignment due to a constant longitudinal length of acoustic waveguide (<NUM>) and blade (<NUM>) from transducer assembly (<NUM>) (see <FIG>) to the distal tip of blade (<NUM>).

In some instances, it may be desirable to longitudinally adjust blade (<NUM>) relative to clamp arm (<NUM>) so as to maintain the predetermined alignment between blade (<NUM>) and clamp arm (<NUM>) with articulation section (<NUM>) in the straight and articulated configurations. Given the constant longitudinal length of acoustic waveguide (<NUM>) and blade (<NUM>), a proximal portion of the acoustic drivetrain, such as transducer assembly (<NUM>) (see <FIG>), may be shifted in order to offset shift at a distal portion of the acoustic drivetrain, such as blade (<NUM>). To this end, a shiftable transducer assembly (<NUM>, <NUM>) (see <FIG>) may be incorporated into ultrasonic surgical instrument (<NUM>) to align blade (<NUM>) with clamp arm (<NUM>) as desired, such as shown in <FIG>. In an alternative example shown in <FIG>, an ultrasonic surgical instrument (<NUM>) has a pin (<NUM>) extending through a node of acoustic waveguide (<NUM>) and distal shaft portion (<NUM>) to fix acoustic waveguide (<NUM>) relative to distal shaft portion (<NUM>). In turn, pin (<NUM>) also longitudinally secures blade (<NUM>) in the predetermined alignment position relative to clamp arm (<NUM>). Still, the disclosure is not intended to be unnecessarily limited to mechanically fixing blade (<NUM>) relative to clamp arm (<NUM>). Moreover, such longitudinal adjustments of one or more portions of the acoustic drivetrain along longitudinal axis (<NUM>) (see <FIG>) may be performed in an alternative ultrasonic surgical instrument (not shown) without a clamp arm (not shown) or even to achieve other alignments relative to the acoustic drivetrain without regard for articulation of articulation section (<NUM>). The disclosure is thus not intended to be unnecessarily limited to use for maintaining the predetermined alignment between clamp arm (<NUM>) and blade (<NUM>) as shown and described herein. In any case, like numbers below indicate like features described above in greater detail.

<FIG> show a third example of an ultrasonic surgical instrument (<NUM>) having end effector (<NUM>) and a second exemplary shaft assembly (<NUM>) with pin (<NUM>) through acoustic waveguide (<NUM>) such that blade (<NUM>) is longitudinally fixed in the predetermined alignment with clamp arm (<NUM>) as discussed above in greater detail. Ultrasonic surgical instrument (<NUM>) further includes a second exemplary base assembly (<NUM>) constructed similarly to base assembly (<NUM>) (see <FIG>), but with a passively shiftable transducer assembly (<NUM>) and a passive system actuator (<NUM>). Shiftable transducer assembly (<NUM>) is movably coupled between housing (<NUM>) and passive system actuator (<NUM>) such that passive system actuator (<NUM>) enables shiftable transducer assembly (<NUM>) to be urged proximally or distally along longitudinal axis (<NUM>). Thereby, shiftable transducer assembly (<NUM>) accommodates longitudinal movement of acoustic waveguide (<NUM>) and blade (<NUM>) for maintaining the predetermined alignment. In the present example, pin (<NUM>) distally pulls on acoustic waveguide (<NUM>) when deflecting end effector away from longitudinal axis (<NUM>) such that shiftable transducer assembly (<NUM>) distally pulls shiftable transducer assembly (<NUM>) toward end effector (<NUM>) and along longitudinal axis (<NUM>). In contrast, pin (<NUM>) proximally pushes on acoustic waveguide (<NUM>) when deflecting end effector toward longitudinal axis (<NUM>) such that shiftable transducer assembly (<NUM>) proximally pushes shiftable transducer assembly (<NUM>) away from end effector (<NUM>) and along longitudinal axis (<NUM>). Shiftable transducer assembly (<NUM>) and system actuator (<NUM>) are thus referred to herein as "passive" given that shiftable transducer assembly (<NUM>) and system actuator (<NUM>) enable movement rather than providing initiating force for such movement. Although, as will be described below in greater detail, shiftable transducer assembly (<NUM>) and system actuator (<NUM>) may still provide force, such as a reactionary force, for maintaining tension and/or compression on acoustic waveguide (<NUM>).

Shiftable transducer assembly (<NUM>) of the present example shown in <FIG> more particularly includes a transducer housing (<NUM>) and a transducer horn (<NUM>) threaded into engagement with acoustic waveguide (<NUM>). Housing (<NUM>), in one example, has a pair of distal mount seats (<NUM>) and a pair of proximal mount seats (<NUM>) configured to longitudinally capture passive system actuator (<NUM>) while simultaneously allowing for longitudinal movement of transducer housing (<NUM>) and transducer horn (<NUM>) through a central space (<NUM>). Passive system actuator (<NUM>) thereby resiliently and translatably supports shiftable transducer assembly (<NUM>) relative to housing (<NUM>) along longitudinal axis (<NUM>), although it will be appreciated that the disclosure is not intended to be unnecessarily limited to resilient or translational mounting within housing (<NUM>).

More particularly, passive system actuator (<NUM>) of the present example includes an annular base seat (<NUM>) rigidly connected to and extending radially outward from transducer housing (<NUM>) as well as a distal annular spring (<NUM>) and a proximal annular spring (<NUM>). Distal annular spring (<NUM>) seats in compression between annular base seat (<NUM>) and distal mount seats (<NUM>) while proximal annular spring (<NUM>) seats in compression between annular base seat (<NUM>) and proximal mount seats (<NUM>). Distal and proximal mounts seats (<NUM>, <NUM>) also laterally secure annular base seat (<NUM>) with transducer housing (<NUM>) on longitudinal axis (<NUM>). With respect to <FIG>, shiftable transducer assembly (<NUM>) is in a proximal position on longitudinal axis (<NUM>) while articulation section (<NUM>) (see <FIG>) is in a straight configuration (see <FIG>). In contrast, with respect to <FIG>, shiftable transducer assembly (<NUM>) is in a distal position on longitudinal axis (<NUM>) while articulation section (<NUM>) (see <FIG>) is in an articulated configuration (see <FIG>). In any longitudinal position between the distal and proximal positions, distal and proximal annular springs (<NUM>, <NUM>) effectively balance force applied by pin (<NUM>) (see <FIG>) while annular base seat (<NUM>) translatably supports transducer housing (<NUM>) relative to housing (<NUM>) of base assembly (<NUM>). As shown in the present example, distal and proximal annular springs (<NUM>, <NUM>) are in compression. More particularly, compression of distal annular spring (<NUM>) increases while compression of proximal annular spring (<NUM>) decreases as shiftable transducer assembly (<NUM>) moves from the proximal position toward the distal position. Also, compression of distal annular spring (<NUM>) decreases while compression of proximal annular spring (<NUM>) increases as shiftable transducer assembly (<NUM>) moves from the distal position toward the proximal position.

Distal and proximal annular springs (<NUM>, <NUM>) are configured to balance annular base seat (<NUM>) with transducer housing (<NUM>) supported therein according to a predetermined balance in any longitudinal position for accommodating movement of acoustic waveguide (<NUM>) resulting from articulation of articulation section (<NUM>) (see <FIG>). In one example, distal and proximal annular springs (<NUM>, <NUM>) balance acoustic waveguide (<NUM>) in tension between the proximal and distal positions. In another example, distal and proximal annular springs (<NUM>, <NUM>) balance acoustic waveguide (<NUM>) in compression between the proximal and distal positions. In still another example, distal and proximal annular springs (<NUM>, <NUM>) balance acoustic waveguide (<NUM>) in compression toward the proximal position and in tension toward the distal position with a neutral, non-compression and non-tension state therebetween. In still yet another example, distal and proximal annular springs (<NUM>, <NUM>) balance acoustic waveguide (<NUM>) in tension toward the proximal position and in compression toward the distal position with another neutral, non-compression and non-tension state therebetween. The disclosure is thus not intended to be unnecessarily limited to maintaining one or more portions of the acoustic drivetrain, such acoustic waveguide (<NUM>), in a particular state of compression or tension.

In use, with respect to <FIG> and <FIG>, linear system actuators (36e, 36f) urge articulation bands (<NUM>) (see <FIG>) to direct movement of articulation section (<NUM>) for deflecting end effector (<NUM>) relative to longitudinal axis (<NUM>). Articulation section (<NUM>) articulates from the straight configuration toward the articulated configuration such that pin (<NUM>) distally pulls acoustic waveguide (<NUM>) with shiftable transducer assembly (<NUM>) from the proximal position toward the distal position to maintain the predetermined alignment between blade (<NUM>) and clamp arm (<NUM>). In this respect, movement of shiftable transducer assembly (<NUM>) is dependent upon articulation of articulation section (<NUM>). Annular base seat (<NUM>) of passive system actuator (<NUM>) supports transducer housing (<NUM>) and transducer horn (<NUM>) as shiftable transducer assembly (<NUM>) translates from the proximal position toward the distal position. In addition, annular base seat (<NUM>) compresses distal annular spring (<NUM>) against distal mount seats (<NUM>), while proximal annular spring (<NUM>) expands, distally urging annular base seat (<NUM>) toward distal mount seats (<NUM>). Distal and proximal annular springs (<NUM>, <NUM>) continue to balance shiftable transducer assembly (<NUM>) and acoustic waveguide (<NUM>) with pin (<NUM>) as articulation section (<NUM>) is positioned in the articulated configuration during use. Thus, blade (<NUM>) remains in the same predetermined alignment with clamp arm (<NUM>) before, during, and after articulation of articulation section (<NUM>). Of course, any alignment may be desired, and the disclosure is not intended to be limited to the alignment of blade (<NUM>) shown and described in the present example. While the present example describes movement of articulation section (<NUM>) from the straight configuration toward the articulated configuration, it will be appreciated that shiftable transducer assembly (<NUM>) and associated components will move in opposite directions from those discussed above when moving articulation section (<NUM>) from the articulated configuration toward the straight configuration. Furthermore, in another example, articulation of articulation section (<NUM>) may be controlled by an operator via a handle assembly (not shown), such as by a knob (not shown) operatively connected to articulation section (<NUM>), rather than a robotic drive (not shown). The disclosure is thus not intended to be unnecessarily limited to use with base assembly (<NUM>) as shown and described herein.

<FIG> show a fourth example of an ultrasonic surgical instrument (<NUM>) having end effector (<NUM>) (see <FIG>) and shaft assembly (<NUM>) without pin (<NUM>) (see <FIG>) through acoustic waveguide (<NUM>) such that blade (<NUM>) may or may not be longitudinally maintained in the predetermined alignment with clamp arm (<NUM>). Ultrasonic surgical instrument (<NUM>) further includes a third exemplary base assembly (<NUM>) constructed similarly to base assembly (<NUM>) (see <FIG>), but with an actively shiftable transducer assembly (<NUM>) and an active system actuator (<NUM>). Shiftable transducer assembly (<NUM>) is movably coupled between housing (<NUM>) and active system actuator (<NUM>) such that active system actuator (<NUM>) urges shiftable transducer assembly (<NUM>) proximally or distally along longitudinal axis (<NUM>). In one example, active system actuator (<NUM>) keys movement of shiftable transducer assembly (<NUM>) to accommodate longitudinal movement of acoustic waveguide (<NUM>) and blade (<NUM>) (see <FIG>) for maintaining the predetermined alignment during articulation. Either shaft assembly (<NUM>) or shaft assembly (<NUM>) (see <FIG>) may be incorporated into ultrasonic surgical instrument (<NUM>) in such an example. In another example, active system actuator (<NUM>) directs movement of shiftable transducer assembly (<NUM>) to position blade (<NUM>) in any longitudinal position relative to shaft assembly (<NUM>) and/or clamp arm (<NUM>) as desired by the operator. The disclosure is thus not intended to be unnecessarily limited to acoustic waveguide (<NUM>) being movable or fixed, such as via pin (<NUM>). Shiftable transducer assembly (<NUM>) and system actuator (<NUM>) are thus referred to herein as "active" given that shiftable transducer assembly (<NUM>) and system actuator (<NUM>) initiate movement by force rather than simply supporting such movement.

Shiftable transducer assembly (<NUM>) of the present example shown in <FIG> more particularly includes a transducer housing (<NUM>) and a transducer horn (<NUM>) threaded into engagement with acoustic waveguide (<NUM>). Active system actuator (<NUM>) of the present example includes gear-rack mechanism (<NUM>) with rotatable drive gear (<NUM>) and translatable rack gear (<NUM>) discussed above in greater detail as well as a transducer coupler (<NUM>) rigidly extending in the proximal direction from rack gear (<NUM>). Transducer coupler (<NUM>) receives transducer housing (<NUM>) to longitudinally secure transducer housing (<NUM>) and transducer horn (<NUM>) relative to rack gear (<NUM>) distally extending therefrom while laterally supporting transducer housing (<NUM>) and transducer horn (<NUM>). Rotatable drive gear (<NUM>) directly engages with rack gear (<NUM>) in the present example to selectively translate shiftable transducer assembly (<NUM>) as desired.

In use, with respect to <FIG> and <FIG>, drive gear (<NUM>) is selectively rotated via robotic drive (not shown) to linearly translate rack gear (<NUM>) along longitudinal axis (<NUM>) as desired. In turn, transducer coupler (<NUM>) urges shiftable transducer assembly (<NUM>) distally or proximally along longitudinal axis (<NUM>) thereby translating acoustic waveguide (<NUM>) and blade (<NUM>) as desired. In one example, active system actuator (<NUM>) keys movement of shiftable transducer assembly (<NUM>) to accommodate longitudinal movement of acoustic waveguide (<NUM>) and blade (<NUM>) for maintaining the predetermined alignment during articulation. Alternatively or in addition, active system actuator (<NUM>) directs movement of shiftable transducer assembly (<NUM>) to position blade (<NUM>) in any longitudinal position relative to shaft assembly (<NUM>) and/or clamp arm (<NUM>) as desired by the operator. In this respect, movement of shiftable transducer assembly (<NUM>) is independent upon articulation of articulation section (<NUM>) such that shiftable transducer assembly (<NUM>) may be moved with or without articulating articulation section (<NUM>). While articulation of articulation section (<NUM>) and/or shiftable transducer assembly (<NUM>) may be controlled by a robotic drive (not shown) as discussed in the present example, an operator may alternatively control articulation of articulation section (<NUM>) and/or shiftable transducer assembly (<NUM>) via a handle assembly (not shown), such as by a knob (not shown) operatively connected to articulation section (<NUM>) and/or shiftable transducer assembly (<NUM>). The disclosure is thus not intended to be unnecessarily limited to use with base assembly (<NUM>) as shown and described herein.

Any one or more of the teaching, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the teachings, expressions, embodiments, examples, etc. described in <CIT>, entitled "Ultrasonic Surgical Instrument with Axisymmetric Clamping," filed on even date herewith; <CIT>, entitled "Ultrasonic Blade and Clamp Arm Alignment Features," filed on even date herewith; and/or <CIT>, entitled " Rotatable Linear Actuation Mechanism," filed on even date herewith.

It should be understood that any of the versions of instruments described herein may include various other features in addition to or in lieu of those described above. By way of example only, in addition to the teachings above, it should be understood that the instruments described herein may be constructed and operable in accordance with at least some of the teachings of <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and/or <CIT>. The disclosures of each of the foregoing patents, publications, and applications are referred to herein. It should also be understood that the instruments described herein may have various structural and functional similarities with the HARMONIC ACE® Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears, and/or the HARMONIC SYNERGY® Ultrasonic Blades. Furthermore, the instruments described herein may have various structural and functional similarities with the devices taught in any of the other references that are referred to herein.

To the extent that there is some degree of overlap between the teachings of the references cited herein, the HARMONIC ACE® Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears, and/or the HARMONIC SYNERGY® Ultrasonic Blades, and the teachings herein relating to the instruments described herein, there is no intent for any of the description herein to be presumed as admitted prior art. Several teachings herein will in fact go beyond the scope of the teachings of the references cited herein and the HARMONIC ACE® Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears, and the HARMONIC SYNERGY® Ultrasonic Blades.

By way of example only, various teachings herein may be readily incorporated into another example of a robotic surgical system, and those of ordinary skill in the art will recognize that various teachings herein may be readily combined with various teachings of any of the following: <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>, the disclosure of which is referred to herein; <CIT>; <CIT>, the disclosure of which is referred to herein; and/or <CIT>, the disclosure of which is referred to herein.

Versions described above may be designed to be disposed of after a single use, or they can be designed to be used multiple times. Upon cleaning and/or replacement of particular parts, some versions of the device may be reassembled for subsequent use either at a reconditioning facility, or by an operator immediately prior to a procedure. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present disclosure.

Claim 1:
An acoustic waveguide (<NUM>) for an ultrasonic surgical instrument, comprising:
(a) a proximal waveguide body portion (<NUM>) defining a longitudinal axis (<NUM>);
(b) a distal waveguide body portion (<NUM>) having an ultrasonic blade (<NUM>) distally projecting therefrom; and
(c) an articulation body portion (<NUM>) extending between the proximal and distal waveguide body portions, wherein the articulation body comprises a first flexible member (<NUM>) and a second flexible member, wherein the first and second flexible members are configured to flex in a full <NUM>-degree range of radial directions through a respective full <NUM>-degree range of radial planes such that the articulation body portion is configured to flex in at least a first direction and a second direction to thereby deflect the ultrasonic blade relative to the longitudinal axis and through a first plane and through a second plane respectively,
and
wherein the second direction is different than the first direction such that the second plane is different than the first plane for multiplanar deflection of the ultrasonic blade relative to the longitudinal axis;
wherein the first flexible member is a flexible member configured to receive an acoustic vibration from the proximal waveguide body portion, and communicate the acoustic vibration from the proximal waveguide body portion to the distal waveguide body portion for driving the ultrasonic blade with the acoustic vibration; and
wherein the first flexible member has a set of predetermined properties and the acoustic vibration has a longitudinal vibrational component and a transverse vibrational component, and wherein the set of predetermined properties of the flexible member are configured to uncouple the longitudinal vibrational component from the transverse vibrational component;
wherein the first flexible member is a first flexible wire (<NUM>) and wherein the first flexible wire has a wire cross-sectional radius, the proximal waveguide body portion has a proximal waveguide radius, and the distal waveguide body portion has a distal waveguide radius, and wherein the wire cross-sectional radius is smaller than the proximal and distal waveguide radii, and
wherein the second flexible member is a second flexible wire.