Rotational limiter for surgical instrument end effector shaft

Abstract

A medical instrument comprises a housing, a working shaft extending from the housing, the working shaft including a rotation mechanism located proximate a proximal portion of the working shaft to facilitate rotation of the working shaft relative to the housing and an intervention device, and a rotation limiter configured to allow the working shaft to rotate relative to the housing, wherein the rotation limiter allows the working shaft to rotate relative to the housing over a finite rotational path that is more than one-hundred-sixty degrees. A rotation limiting assembly for a forceps comprises a hub configured to receive a shaft of the forceps so that the shaft and the hub can rotate about an axis within a housing of the forceps, and a pin-and-slot interface configured to limit rotation between the hub and the housing to allow the hub to rotate over-three-hundred-sixty degrees before limiting rotation.

Description

ROTATIONAL LIMITER FOR SURGICAL INSTRUMENT END EFFECTOR SHAFTPRIORITY CLAIM

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 63 / 601,628, filed November 21, 2023, the contents of which have been incorporated herein by reference.TECHNICAL FIELD

[0002] This document pertains generally, but not by way of limitation, to systems and methods for actuating and positioning end effectors of medical devices. In particular, the systems and methods can be used with a forceps having an actuatable jaw and / or a blade that can be rotated about an axis.BACKGROUND

[0003] Medical devices for diagnosis and treatment, including but not limited to forceps, are used for medical procedures such as laparoscopic and open surgeries. Forceps can be used to manipulate, engage, grasp, or otherwise affect an anatomical feature, such as a vessel or other tissue. Such medical devices can include an end effector that is one or more of rotatable, openable, closeable, extendable, retractable and capable of supplying an input such as electromagnetic energy or ultrasound.

[0004] For example, jaws located at a distal end of a forceps are typically actuated via elements at a handpiece of the forceps to cause the jaws to open and close and thereby engage the vessel or other tissue. Forceps may also include an extendable and retractable blade, such as blades that can be extended distally between a pair of jaws. Furthermore, the jaws can be rotated about an axis to facilitate actuation in different orientations.

[0005] There is a need for improved medical devices, including forceps. Aspects described herein provide a variety of improvements over conventional forceps and other medical devices having a handpiece including an actuation system that controls an end effector that can be rotated.SUMMARY

[0006] In an example, a medical instrument can comprise a housing, a working shaft extending from the housing, the working shaft including a rotation mechanism located proximate a proximal portion of the working shaft to facilitate rotation of the working shaft relative to the housing and an intervention device proximate a distal portion of the working shaft, and a rotation limiter configured to allow the working shaft to rotate relative to the housing, wherein the rotation limiter allows the working shaft to rotate relative to the housing over a finite rotational path that is more than one-hundred-sixty degrees.

[0007] In another example, a rotation limiting assembly for a forceps can comprise a hub configured to receive a shaft of the forceps so that the shaft and the hub can rotate about an axis within a housing of the forceps, and a pin-and- slot interface configured to limit rotation between the hub and the housing, the pin-and-slot interface allowing the hub to rotate over-three-hundred-sixty degrees before limiting rotation.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various examples discussed in the present document.

[0009] FIG. 1A illustrates a side view of a forceps showing jaws in an open position.

[0010] FIG. IB illustrates a side view of the forceps of FIG. 1A showing the jaws in a closed position.

[0011] FIG. 2 illustrates an exploded view of some components of the forceps of FIG. 1A.

[0012] FIG. 3 A illustrates a first partial cross-section view of a portion of the forceps of FIG. 1A.

[0013] FIG. 3B illustrates a second partial cross-section view of a portion of the forceps of FIG. 1A.

[0014] FIG. 3C illustrates a close-up exploded view of a portion of the forceps of FIG. 1A.

[0015] FIG. 3D illustrates a third partial cross-section view of the forceps of FIG. 3 A showing a drive shaft motion transfer body in a rotated position.

[0016] FIG. 3E illustrates a fourth partial cross-section view of the forceps of FIG. 3 A showing the drive shaft motion transfer body in the rotated position of FIG. 3D.

[0017] FIG. 4A illustrates a partial cross-sectional view of the forceps of FIG. 1 A showing a lever in a distal position (e.g., unactuated position).

[0018] FIG. 4B illustrates a partial cross-sectional view of the forceps of FIG. 1 A showing the lever moved proximally (e.g., an actuated position).

[0019] FIG. 4C illustrates a partial cross-sectional view of the forceps of FIG. 1 A showing the lever moved further proximally (e.g., a force limiting state, an over-travel position).

[0020] FIG. 5A is an isometric view of a first end of a rotational actuator of the present disclosure that permits rotation greater than three-hundred- sixty degrees.

[0021] FIG. 5B is an isometric view of a second end of the rotational actuator of FIG. 5 A comprising a shaft and a collar.

[0022] FIG. 5C is a schematic cross-sectional view of the rotational actuator of FIG. 5 A and FIG. 5B disposed within a housing for a handpiece of a medical instrument.

[0023] FIG. 6A is an isometric view of the shaft of FIG. 5 A and FIG. 5B showing a pin and a tab.

[0024] FIG. 6B is a cross-sectional view of the shaft of FIG. 6A taken at section 6B - 6B to show relative circumferential positions of the pin and tab.

[0025] FIG. 6C is a cross-sectional view of the shaft of FIG. 6B taken at section 6C - 6C to show relative axial positions of the pin and tab.

[0026] FIG. 7A is an isometric view of a first end of the collar of FIG. 5 A and FIG. 5B showing a slot and a flange.

[0027] FIG. 7B is an isometric view of a second end of the collar of FIG. 7A showing the slot and the flange.

[0028] FIG. 7C is a cross-sectional view of the collar of FIG. 7A taken at section 7C - 7C to show axial positioning of the slot and the tab.

[0029] FIG. 7D is a cross-sectional view of the collar of FIG. 7A taken at section 7D - 7D to show a circumferential extent of the slot.

[0030] FIG. 8 A is a cross-sectional view of the rotational actuator of FIG.5 A and FIG. 5B showing the collar and the shaft at a first rotational extreme position.

[0031] FIG. 8B is a cross-sectional view of the rotational actuator of FIG. 5 A and FIG. 5B with the collar at the first rotational extreme position and the shaft rotated counter-clockwise to the opposite side of the slot of the collar.

[0032] FIG. 8C is a cross-sectional view of the rotational actuator of FIG. 5A and FIG. 5B showing the collar and the shaft rotated counter-clockwise to a second rotational extreme position.

[0033] FIG. 9A is an isometric view of a first end of a shaft of the present disclosure including a helical slot.

[0034] FIG. 9B is an isometric view of a second end of the shaft of FIG. 9A showing a backside of the helical slot.

[0035] FIG. 9C is a schematic cross-sectional view of the shaft of FIG. 9A and FIG. 9B located within a housing of a handpiece of a surgical instrument having a moveable stop.DETAILED DESCRIPTION

[0036] A medical device including a handpiece that operates an end effector allows a surgeon to control the end effector of the device to actuate one or more functions of the end effector. Actuation of the end effector can be facilitated by one or more actuation systems of the handpiece that can retract, extend or rotate one or more shafts to control the actions of the end effector.

[0037] The present inventors have recognized, among other things, that conventional medical devices including a handpiece that actuates an end effector can be improved to increase capabilities of the medical device, such as by allowing tissue to be engaged more expediently, and increase a user’s experience, such as by reducing fatigue and discomfort. For example, some medical device include end effectors that are mounted to shafts can be rotated along a longitudinal, proximal -distal, axis. However, in order to prevent potential damage to other components extending through the shaft, limits are placed on the rotation of the shaft. For example, many end effectors include connections to electrical energy to provide desired cauterizing or ablation effects. The electrical energy can be delivered through wiring extending throughthe shaft. Thus, to avoid twisting and potential damage to the wiring, limits are placed on the ability of the shaft to unlimitedly rotate. Typical rotational limits comprise a simple stop located in a housing adjacent the shaft. The stop can interact with a tab connected to the shaft. Thus, rotation of the shaft is less than three-hundred- sixty degrees from one side of the stop to the other.

[0038] Limitations on the ability of the shaft to rotate can interfere with a user’s, e.g., a surgeon’s, ability to perform the desired procedure. For example, thee end effector can be rotated to obtain a better angle of approach to target tissue, e.g., tissue to be treated or removed. Sometimes the target tissue is located beyond the current angle of approach of the end effector, and it is desirable for the user to reorientate the end effector into a different rotational, e.g., circumferential position. However, sometimes the rotational stop is located before the desired circumferential position, thereby requiring the user to rotate the end effector in the opposite direction to reach the desired orientation. This can result in the rotational actuator having to be rotated further than otherwise would have been needed if the circumferential stop were not present.

[0039] Such a problem can be exacerbated by the ergonomics of rotational actuators. For example, some rotational actuators are designed to by operated by a single finger or thumb while a hand of the user is grasping the handpiece for the medical instrument, thereby freeing the other hand to perform other tasks. Thus, in order to actuate the rotational actuator a finger or thumb can push a knob, dial or collar back and forth to change the rotational angle of the end effector. It can be easier to provide actuation from a finger or thumb in one direction rather than the other. Thus, repetitive actuation of the knob, dial or collar can lead to fatigue and stress. Further, having to rotate the knob, dial or collar in one direction longer than would be needed to rotate in the opposite direction to reach target tissue due to the presence of the stop can increase the time it takes to perform a procedure.

[0040] This disclosure is generally related to medical devices, such as surgical or medical instruments. Although the present application is described with reference to a forceps, other end effectors, or intervention devices, can be used with and operated by the handpiece described herein. In addition, other handpieces can be connected to and can control the end effectors described herein. This disclosure includes examples of handpieces including one or morerotational actuation systems, examples of end effectors, and examples where the disclosed rotational actuation systems and end effectors can be used together in a medical device.

[0041] The forceps can include a medical forceps, a cutting forceps, an electrosurgical forceps, or any other type of forceps. The forceps can include an end effector that is controlled by a handpiece including an actuation system to be one or more of: rotatable, openable, closeable, extendable, and capable of supplying electromagnetic energy or ultrasound. For example, jaws located at a distal end of the forceps can be actuated via one or more actuators at a handpiece of the forceps to cause the jaws to open, close and rotate to engage a vessel or other tissue. Forceps may also include an extendable and retractable blade, such as blades that can be extended distally in between a pair of jaws to separate a first tissue from a second tissue.

[0042] The present disclosure can provide solutions to the aforementioned problems and other problems by providing rotational actuators that allow a shaft of an end effector to be rotated beyond three-hundred-sixty degrees while still also providing a finite rotational path to prevent damage to components within the shaft. The rotational actuators of the present disclosure can allow rotation of an end effector over the shortest path possible without having to take into account of the location of a stop. That is, since the rotational actuators of the present disclosure can provide rotational actuation over a circumferential path that is beyond three-hundred-sixty degrees, including seven-hundred-twenty degrees of rotation or more, target tissue can typically be located within one- hundred-eighty degrees of rotation of the end effector or less.

[0043] FIG. 1A illustrates a side view of a forceps 1000 with jaws 1012 in an open position. FIG. IB illustrates a side view of the forceps 1000 with the jaws 1012 in a closed position. FIG. 2 illustrates an exploded view of some components of the forceps 1000 of FIG. 1A. FIGS. 1A, IB and 2 are described together. Directional descriptors such as proximal and distal are used within their ordinary meaning in the art. The proximal direction P and distal direction D are indicated on the axes provided in FIG. 1 A and FIG. 2. FIG. 2 also shows the lateral directions L and L’, as well as top T and bottom B directions, which are defined when the forceps 1000 is held level with respect to a ground G in an upright orientation as shown in FIG. 1 A. Opposite to the lateral directions L andL’, is the medial direction, in other words, the medial direction is towards the centerline, or a longitudinal axis of the forceps 1000 (FIG. IB).

[0044] The illustrative forceps 1000 can include a handpiece 1001 at a proximal end, and an end effector 1002 at a distal end. An intermediate portion 1006 can extend between the handpiece 1001 and the end effector 1002 to operably couple the handpiece 1001 to the end effector 1002. Various movements of the end effector 1002 can be controlled by one or more actuation systems of the handpiece 1001. In the illustrative example, the end effector 1002 can include the jaws 1012 that are capable of opening and closing. The end effector 1002 can be rotated along a longitudinal axis Al (FIG. IB) of the forceps 1000. The end effector 1002 can include a cutting blade 1032A (FIG. 2) and an electrode for applying electromagnetic energy. All actuation system functions and all end effector actions are not required in all examples. The functions described herein can be provided in any combination.

[0045] An overview of features of the forceps 1000 is provided in FIGS. 1 A, IB, 2, 3 A - 3E and 4A - 4C. The illustrated actuators provide transmission of forces received from a user via clamping and rotational actuators (e.g., a lever 1024 and a rotational actuator 1030), to the jaws 1012 of the forceps 1000 to actuate clamping and rotation of the jaws 1012. Further detailed illustration of examples of rotational actuators of the present disclosure are provided in FIG. 5A - FIG. 9C.

[0046] As shown broadly in FIGS. 1 A and IB, with support from FIG. 2, the forceps 1000 can include the jaws 1012, a housing 1014, a lever 1024, a drive shaft 1026, an outer shaft 1028 (e.g., a working shaft), a rotational actuator 1030, a blade assembly (a blade shaft 1032 and a blade 1032A of FIG. 2), a trigger 1034 and an activation button 1036. In this example, the end effector 1002, or a portion of the end effector 1002 can be one or more of: opened, closed, rotated, extended, retracted, and electromagnetically energized (e.g., electrically energized). In some examples, the energy can be radio-frequency energy. In examples, electrical energy can be delivered to end effector 1002 via wires extending from cable 1004 (FIG. 1 A) into housing 1014 and into outer shaft 1028.

[0047] To operate the end effector 1002, the user can displace the lever 1024 proximally by applying Force Fl (FIG. IB) to drive the jaws 1012 from the openposition (FIG 1 A) to the closed position (FIG. IB). In the example of forceps 1000, moving the jaws 1012 from the open position to the closed position allows a user to clamp down on and compress a tissue. The handpiece 1001 can also allow a user to rotate the end effector 1002. For example, rotating rotational actuator 1030 causes the end effector 1002 to rotate by rotating both the drive shaft 1026 and the outer shaft 1028 together.

[0048] In some examples, with the tissue compressed between the jaws 1012, a user can depress the activation button 1036 to cause an electromagnetic energy, or in some examples, ultrasound, to be delivered to the end effector 1002, such as to an electrode. Application of electromagnetic energy can be used to seal or otherwise affect the tissue being clamped. In some examples, the electromagnetic energy can cause tissue to be coagulated, cauterized, sealed, ablated, desiccated or can cause controlled necrosis. Example electrodes are described herein, but electromagnetic energy can be applied to any suitable electrode.

[0049] The handpiece 1001 can enable a user to extend and retract a blade 1032A attached to a distal end of a blade shaft 1032 (FIG. 2). The blade 1032A can be extended by displacing the trigger 1034 proximally. The blade 1032A can be retracted by allowing the trigger 1034 to return distally to a default position. The default position of the trigger 1034 is shown in FIG. 1 A. In some examples, the handpiece 1001 can include features that inhibit the blade 1032A from being extended until the jaws 1012 are at least partially closed, or fully closed.

[0050] The forceps 1000 can be used to perform a treatment on a patient, such as a surgical procedure. In an example, a distal portion of the forceps 1000, including the jaws 1012, can be inserted into a body of a patient, such as through an incision or another anatomical feature of the patient’s body. While a proximal portion of the forceps 1000, including housing 1014 remains outside the incision or another anatomical feature of the body. Actuation of the lever 1024 causes the jaws 1012 to clamp onto a tissue. The rotational actuator 1030 can be rotated via a user input to rotate the jaws 1012 for maneuvering the jaws 1012 at any time during the procedure. Activation button 1036 can be actuated to provide electrical energy to jaws 1012 to coagulate, cauterize or seal the tissuewithin the closed jaws 1012. Trigger 1034 can be moved to translate the blade 1032 A distally to cut the tissue within the jaws 1012.

[0051] In some examples, the forceps 1000, or other medical device, may not include all the features described or may include additional features and functions, and the operations may be performed in any order. The handpiece 1001 can be used with a variety of other end effectors to perform other methods.

[0052] As shown in the combination of FIG. 1 A, FIG. IB and FIG 2, the forceps 1000 can include various components. For example, a first housing portion 1016 and a second housing portion 1018. As shown in FIG. 2, the first housing portion 1016 and the second housing portion 1018 can mate at a coupling joint 1017. The housing 1014 can include, or be coupled to, a handle portion 1020A and 1020B, such as a fixed handle that is configured to be held in the hand of a user during use.

[0053] The housing 1014 can be a frame that provides structural support between components of the forceps 1000. The housing 1014 is shown as housing at least a portion of the actuation systems associated with the handpiece 1001 for actuating the end effector 1002. However, some or all of the actuation components need not necessarily be housed within the housing 1014.Components described herein may be completely housed within the housing 1014 through all or a portion of the range of motion of the components of the actuation system; partially housed through all or a portion of the range of motion of the components of the actuation system; or completely external to the housing 1014 during all or a portion of the range of motion of the components of the actuation system associated with the handpiece 1001. In some examples, the housing 1014 provides a rigid structure for attachment of components, but the housing 1014 does not necessarily house the components completely, or only houses a portion of some of the components.

[0054] With continued reference to FIG. 1 A, FIG. IB and FIG. 2, the drive shaft 1026 can extend through the housing 1014 and out of a distal end of the housing 1014, or distally beyond housing 1014. The jaws 1012 can be connected to a distal end of the drive shaft 1026. The outer shaft 1028 can be a hollow tube positioned around the drive shaft 1026. A distal end of the outer shaft 1028 can be located adjacent the jaws 1012 and the jaws 1012 can be connected to the outer shaft 1028. The distal ends of the drive shaft 1026 andthe outer shaft 1028 can be rotationally locked (e.g., rotationally constrained) to the jaws 1012. The rotational actuator 1030 can be positioned around the distal end 1900 of the housing 1014. In the illustrative example, the rotational actuator 1030 is indirectly connected to a proximal end of the outer shaft 1028 by an outer hub 1060, however, in some examples the rotational actuator 1030 can be directly connected to the proximal end of the outer shaft 1028 or can integrally include the features of the outer hub 1060. In some examples, various rotational constraints described herein can be employed independently. For example, distal end 1900 can include stop 1902 and hub 1060 can include flange 1904 for engaging stop 1902. Some examples can employ a single rotational constraint between the rotational actuator 1030 and the jaws 1012, while in other examples, the rotational constraint can include multiple rotational constraints at different locations along the longitudinal axis Al, such as a first rotational constraint proximate or within the handpiece 1001, and a second rotational constraint proximate the end effector 1002 and distal of the handpiece 1001. As described herein, some rotational constraints can allow outer hub 1060, along with outer shaft 1028, to rotate greater than three-hundred-sixty degrees to allow for greater usability among other things.

[0055] The outer shaft 1028 can extend distally beyond the rotational actuator 1030. The blade shaft 1032 can extend through the drive shaft 1026 and the outer shaft 1028. A distal end of the blade shaft 1032 including the blade 1032A can be located adjacent to the jaws 1012. A proximal end of the blade shaft 1032 can be within the housing 1014.

[0056] A proximal portion 1034A (FIG. 2) of the trigger 1034 can be connected to the blade shaft 1032 within the housing 1014. A distal portion 1034B (FIG. 2) of the trigger 1034 can extend outside of the housing 1014 adjacent, and in some examples, nested with the lever 1024 in the default or unactuated positions shown in FIG. 1 A. Activation button 1036 can be coupled to the housing 1014. Activation button 1036 can actuate electronic circuitry within housing 1014 that can send electromagnetic energy through forceps 1000 to the jaws 1012. When the user presses on the activation button 1036, the activation button 1036 can move relative to the housing 1014. For example, when the activation button 1036 is pressed, an electrical switch on a flexible printed circuit board that is secured to the housing 1014 can be closed. Forceps1000 can include wiring and electrical components such as a dome switch that can be actuated by the activation button 1036. In some examples, the activation button 1036 or the electronic circuitry may reside outside the housing 1014 but may be operably coupled to the housing 1014 and the end effector 1002. In some examples, activation of the forceps 1000 can be accomplished by a foot or knee actuated switch.

[0057] As shown in the exploded view of a portion of the forceps 1000 in FIG. 2, the forceps 1000 can include the handpiece 1001 having components for an actuation system, the end effector 1002, the intermediate portion 1006, the jaws 1012, the housing 1014 (including the first housing portion 1016, the second housing portion 1018, the handle portion 1020A and 1020B, the stabilizing flange 1021, and a recess or opening 1021 A), the handle locking mechanism 1022, the lever 1024, the drive shaft 1026 (including the first horizontal slot 1069A and the second horizontal slot 1069B, the outer shaft 1028, the rotational actuator 1030, the blade shaft 1032, the blade 1032A the trigger 1034, and the activation button 1036, a first pin 1038, a lever return spring 1040, a coupling link 1042, a second pin 1044, a drive link 1046, a third pin 1048, a fourth pin 1050, a drive shaft motion transfer body 1052 (hereinafter, drive body 1052 or slider block), a force-limiting spring 1054, a clip 1056, an Ciring 1058, an outer hub 1060, a nose 1062, a spool 1064 (e.g., cut block or second drive shaft motion transfer body), a cross pin 1066 (e.g., a blade pin), and a trigger return spring 1068. The handle locking mechanism 1022 can be, for example, of the type described in United States Patent Application 15 / 941,205 to Boone, titled “Forceps Including a Pre-loaded Handle Latch” filed on March 30, 2018, the disclosure of which is incorporated by reference in its entirety. Furthermore, the components which make up the actuation system can be, for example, of the type described in United States Patent Application 15 / 839,218 to Butler titled “Laparoscopic Forceps Assembly with An Operable Mechanism” filed on December 12, 2017, the disclosure of which is incorporated by reference in its entirety.

[0058] As a general overview of the component interaction of the handpiece1001 of the forceps 1000, the forceps 1000 can include the drive body 1052 being constrained to the drive shaft 1026 to transfer motion to the drive shaft 1026, thereby operating the jaws 1012. However, in a force limiting state (e.g.,position), the drive body 1052 can be slidable with respect to the drive shaft 1026. Thus, the forceps 1000 can be configured to limit a force on the jaws 1012 to protect the jaws 1012 from damage when the lever 1024 is being closed with the jaws 1012 stuck in an open or partially open position.

[0059] The drive body 1052 along with the clip 1056 can lock the drive shaft 1026 to the rotational actuator 1030 such that the drive shaft 1026 and the outer shaft 1028 are rotationally locked (e.g., rotationally constrained) together at a proximal portion of the drive shaft 1026 and the outer shaft 1028 proximate the rotational actuator 1030. Further, the forceps 1000 can include the trigger 1034, the spool 1064 proximal to the drive body 1052 and connected to the trigger 1034, and a trigger return spring 1068 positioned between the drive body 1052 and the spool 1064 to bias the blade shaft 1032 with blade 1032A proximally but allow movement of the blade 1032A distally to perform a cut, while improving the design of the forceps.

[0060] FIGS. 3A, 3B, 3C, 3D and 3E focus on the clamping and rotational aspects of the forceps and will be described together with support from FIGS.1 A, IB and 2. Some components related to the cutting functions of the forceps of FIG. 1 A are absent in FIGS. 3A, 3B and 3C to provide better visibility of other components. While FIGS. 3A, 3B, 3C, 3D and 3E illustrate components that make up the actuation system of the handpiece 1001, the function and interrelationship of the components are described throughout this disclosure.

[0061] FIG. 3 A illustrates a first partial cross-section view of a portion of the forceps 1000 of FIG. 1A, FIG. IB and FIG. 2, in accordance with at least one example. The lever 1024, the drive shaft 1026, the drive body 1052, the forcelimiting spring 1054, the clip 1056, the O-ring 1058 and the outer shaft 1028 are not shown in cross section. FIG. 3B illustrates a second partial cross-section view of a portion of the forceps 1000, in accordance with at least one example. The drive shaft 1026 and the outer shaft 1028 are not shown in cross-section. FIG. 3C illustrates a close-up exploded view of a portion of the forceps 1000 of FIG. 1 A, in accordance with at least one example. FIG. 3D illustrates a third partial cross-section view of the forceps 1000 of FIG. 3 A showing the drive body 1052 in a rotated position, in accordance with at least one example. The drive body 1052, the force-limiting spring 1054, the O-ring 1058, and the outer shaft 1028 are not shown in cross-section. FIG. 3E illustrates a fourth partialcross-section view of the forceps 1000 of FIG. 3 A showing the drive body 1052 in the rotated position of FIG. 3D, in accordance with at least one example. The outer shaft 1028 is not shown in cross section.

[0062] FIGS. 3A, 3B, 3C, 3D and 3E, described together with most components shown in the exploded view of FIG. 3C, include the housing 1014 (including the first housing portion 1016, the handle portion 1020 A, and stabilizing flange 1021), the lever 1024, the first pin 1038, the drive shaft 1026, the lever return spring 1040, the coupling link 1042 can reside within a lever recess 1025, the second pin 1044, the drive link 1046, the third pin 1048, the fourth pin 1050, a drive motion transfer assembly 1051, the drive body 1052, the force-limiting spring 1054, the clip 1056, the O-ring 1058, the outer shaft 1028, the outer hub 1060, a sleeve 1061, the rotational actuator 1030, and the nose 1062. The drive shaft 1026 includes the first horizontal slot 1069A, the second horizontal slot 1069B, a first vertical slot 1070A, and a second vertical slot 1070B, which can be an opening extending through the drive shaft 1026, or a recess or deformation in the drive shaft 1026. The drive body 1052 (shown in further detail in other drawings herein as well) can include a body portion 1072, an anchor portion 1074 (including a distal spring seat 1076 and a rotational keying slot 1078), a cylindrical portion 1080, a window portion 1082 (including a first window 1084 A and a second window 1084B, see FIG. 3C), a neck portion 1086, a collar 1088 (such as proximal collar 1088 including a drive surface 1090A and a second distal spring seat 1091, see FIGS. 3B and 3C for a close-up view), and a passageway 1092 (e.g. a channel, a bore, a recess, or an aperture extending therethrough). The sleeve 1061 can include a flange 1094. In some examples, such as an example where the sleeve 1061 is omitted, the outer shaft 1028 can include the flange 1094. The outer hub 1060 can include groove 1096, interior surface 1098, and the anti-rotation key 1100 (FIGS. 3D and 3E).

[0063] The first and second horizontal slots 1069 A, 1069B can extend longitudinally along the drive shaft 1026, in an axial direction, parallel to longitudinal axis Al (FIG. IB). In other words, the first and second horizontal slots 1069A, 1069B can be described as extending horizontally when the drive shaft 1026 is held level. In some examples, the first and second vertical slots 1070A may extend along or within a plane perpendicular to the longitudinal axis Al.

[0064] The drive shaft 1026 can include the first vertical slot 1070A on a first side and the second vertical slot 1070B on a second side (FIG. 3B and FIG. 3C). The vertical slots 1070A and 1070B can be perpendicular to the longitudinal axis Al (FIG. IB) of drive shaft 1026. The first vertical slot 1070A and second vertical slot 1070B can extend into the drive shaft 1026 from an exterior surface of the drive shaft 1026. The first vertical slot 1070A and the second vertical slot 1070B can be sized to accept the clip 1056. In some examples, the clip 1056 can be ridged and can be accepted onto the drive shaft 1026 without distorting the shape of the clip 1056. In some examples, the drive shaft 1026 can have a single vertical slot 1070A or 1070B. The first and second vertical slots 1070A, 1070B can be provided as an opening / aperture or as a deformation with or without an opening through the drive shaft 1026.

[0065] As shown in the combination of FIGS. 3A-3E, the drive body 1052 can include the body portion 1072 and the anchor portion 1074 connected, or integrally formed, at distal end of the body portion 1072. The anchor portion 1074 can extend outwardly from an outer surface of body portion 1072. As such, the anchor portion 1074 can include the distal spring seat 1076 at a proximal end surface of the anchor portion 1074. The distal spring seat 1076 can be connected to a distal end of the body portion 1072.

[0066] As shown in FIGS. 3C, 3D and 3E, and as shown in further detail in other figures herein, the anchor portion 1074 can include the rotational keying slot 1078. The rotational keying slot 1078 can be horizontal slot, or a slot extending parallel to the longitudinal axis Al of the drive shaft 1026 (Al is shown in FIG. IB). The rotational keying slot 1078 can extend into a side of the body portion 1072. In alternate examples, the drive body 1052 may have any number of the rotational keying slot(s) 1078. In some examples, the rotational keying slot 1078 can be any other suitable keying interface known in the art and are not necessarily provided as a slot. The interaction between the rotational keying slot 1078 and an anti-rotation key 1100 of the outer hub 1060 is further described herein. The rotational keying slot 1078 and the anti -rotation key 1100 on the outer hub 1060 can be any type of interface that limits relative rotation between the drive body 1052 and the outer hub 1060. For example, the rotational keying slot 1078 can be a protrusion instead of a slot to be received by the anti -rotation key 1100 that is a slot, recess or groove of the outer hub 1060 inorder to provide the relative anti -rotation features between the drive body 1052 and the outer hub 1060.

[0067] The cylindrical portion 1080 of the drive body 1052 can be connected to, or integrally formed with, the distal end of the anchor portion 1074. The cylindrical portion 1080 can be sized to accept the O-ring 1058.

[0068] As shown in the exploded view of FIG. 3C, and in additional detail in other figures herein, the window portion 1082 can include the first window 1084 A extending through the first side of body portion 1072 and the second window 1084B opposite the first window 1084 A and extending through the second side of body portion 1072. Although described as a window, in some examples the window portion 1082 may be provided as a track, such a window or track need not necessarily be bounded on all sides, and sections of the window or track may not extend entirely through the body portion 1072.

[0069] As shown in FIGS. 3A, 3B and 3C, the neck portion 1086 of the drive body 1052 can be connected to a proximal end of the body portion 1072. The neck portion 1086 can have an outer diameter smaller than the outer diameter of the body portion 1072 (e.g., a minor diameter surface). The collar 1088 can be connected to a proximal end of the neck portion 1086. The collar 1088 can have an outer diameter greater than the outer diameter of the neck portion 1086 and less than an inner diameter of the force-limiting spring 1054.

[0070] The collar 1088 can include the drive surface 1090 A at a distal end surface of the collar 1088 and the second distal spring seat 1091 at a proximal end of the collar 1088, or a proximal end of the drive body 1052. As such, the drive surface 1090 A can be fixedly connected to or integrally molded to the proximal end of the neck portion 1086. Although the neck portion 1086 and associated flanges, such as drive surface 1090A and the second distal spring seat 1091 are shown and described as being located or connected to a proximal end of the body portion 1072, they could be located elsewhere on the drive body 1052, such as along a central portion or distal portion of the drive body 1052, such as distal of the distal spring seat 1076.

[0071] The passageway 1092 in the drive shaft 1026 (FIG. 3B, 3C) can be shaped to accept the drive shaft 1026. The passageway 1092 can be a cylindrical or non-cylindrical aperture extending through the cylindrical portion 1080, theanchor portion 1074, the body portion 1072, the window portion 1082, the neck portion 1086, and the collar 1088.

[0072] The drive shaft 1026 can extend through the passageway 1092 (FIG. 3B) of the drive body 1052 such that the drive body 1052 can be positioned around at least a portion of the drive shaft 1026. The force-limiting spring 1054 can be positioned on the body portion 1072 and over the window portion 1082 of the drive body 1052. A distal end of the force-limiting spring 1054 can contact the distal spring seat 1076. The clip 1056 can be positioned on the window portion 1082 of the drive body 1052 and can connect to drive shaft 1026 at the first vertical slot 1070A and the second vertical slot 1070B. Examples of clips and windows are described further herein, and for example, in FIGS. 4A, 4B, and 4C.

[0073] As shown in FIGS. 3A and 3B, a proximal end of the force-limiting spring 1054 can contact a distal end surface of the clip 1056. As such, the forcelimiting spring 1054 can be positioned on the drive body 1052 between the distal spring seat 1076 of anchor portion 1074 and the clip 1056. In this arrangement, the clip 1056 is fixed to the drive shaft 1026 but can be longitudinally movable with respect to the drive body 1052 within and along window portion 1082 (FIGS. 4A, 4B, 4C) when a preload on the force-limiting spring 1054 is exceeded by the force applied to the lever 1024. A clip support surface of the body portion 1072 can be adjacent a proximal end of the window portion 1082, and a distal support surface of the body portion 1072 can be adjacent a distal end of the window portion 1082. In some examples, the clip support surface and the distal support surface can function as longitudinal stops for the clip 1056 and impose the preload on the force-limiting spring 1054. In an example, the preload can be in a range between 50-150 Newtons. In a possibly more preferred examples, to improve user experience, the preload can be in a range between 70-90 Newtons, or 135-155 Newtons, depending on the design. Unlike conventional clips, the clip 1056 can be configured to support such high preloads in combination with features of the clip 1056 that couple the clip 1056 to the drive body 1052 and the drive shaft 1026. One of the benefits of such ranges in combination with the forceps 1000 design, including the design of clip 1056, is that such preloads can provide adequate sealing pressure on tissue with jaw 1012, without requiring an excessive input Force Fl to actuate lever 1024.Furthermore, a single actuating jaw can deliver roughly twice the sealing pressure at the jaws 1012 than a dual-actuating jaw, given the same preload on the force-limiting spring 1054.

[0074] To cause driving of the jaws 1012 between the open and closed positions shown in FIG. 1A and IB, the lever 1024 is moved proximally or distally which moves the drive body 1052 proximally or distally. The drive link 1046 can be operably coupled to the housing 1014 and the drive body 1052 such that the drive link 1046 is configured to transfer a force received at the lever 1024 into a linear motion of the drive body 1052 and the drive shaft 1026 relative to the housing 1014. For example, the drive link 1046 can be connected to the drive body 1052 at the neck portion 1086. The legs of drive link 1046, shown in FIG. 3C, can fit around the neck portion 1086. When the lever 1024 is moved proximally, the drive link 1046 can contact and push against the drive surface 1090A of the collar 1088. The location of the drive surface 1090A is shown generally in the cross-sectional view of FIGS. 3B and 3C. In contrast, when the lever 1024 is moved distally, the drive link 1046 can move distally, contacting and pushing against a proximal end surface 1090B of body portion 1072 of drive body 1052.

[0075] During a surgical procedure, carbon dioxide or other gas may be used for insufflation, which introduces a pressure differential between the body cavity and the external environment. As shown in FIGS. 3 A- 3E, to prevent leakage, the O-ring 1058 can create a seal between the drive shaft 1026 and the outer hub 1060 so that the pressure differential between the body cavity in which the distal portion of forceps 1000 is positioned and the external environment in which the proximal portion of forceps 1000 is located, is maintained (e.g., pneumatically sealed, substantially pneumatically sealed). In some examples, the O-ring 1058 can be positioned adjacent and distal to the cylindrical portion 1080. Likewise, sealing features within the drive shaft 1026, which can be a hollow tube, can provide similar sealing capabilities to prevent the leakage of air from the body cavity to the external environment in which the proximal portion of forceps 1000, is located. Such sealing features can include a guide plug.

[0076] The sleeve 1061 or the outer shaft 1028 can include the flange 1094 at a proximal end of the sleeve 1061 or the outer shaft 1028. In the example shown, the sleeve 1061 includes the flange 1094. In some examples, the flange1094 can be welded to, or formed in, the sleeve 1061 or the outer shaft 1028. The flange 1094 can fit within the groove 1096 of outer hub 1060. The flange 1094 can improve the ability to affix the sleeve 1061 or outer shaft 1028 to the outer hub 1060. For example, the flange 1094 can fit in the groove 1096 in the outer hub 1060. The groove 1096 can form a ring in the interior surface 1098 of the outer hub 1060. In some examples, the outer hub 1060 can be molded to the outer shaft 1028. In another example, the outer hub 1060 can be over-molded on to the sleeve 1061. In such a case, there is not necessarily a groove 1096, but the shape of the outer hub 1060 that accepts the flange 1094 can be formed by the over-molding of the outer hub 1060 onto the flange 1094.

[0077] To rotationally fix the outer hub 1060 to the drive body 1052, as shown in FIGS. 3D and 3E, the anti-rotation key 1100 can include a ridge that extends out of the interior surface 1098 of the outer hub 1060 into a channel of the outer hub 1060. For example, the anti-rotation key 1100 can be sized to fit within the rotational keying slot 1078 of the anchor portion 1074. The rotational keying slot 1078 can accepts the anti-rotation key 1100, which can be positioned within the rotational keying slot 1078 such that the rotational keying slot 1078 can be linearly translated, or longitudinally moved, along the anti-rotation key 1100.

[0078] The flange 1094 and the groove 1096 or other formation can connect and lock the outer shaft 1028 to the outer hub 1060. The anti -rotation key 1100 and rotational keying slot 1078 can connect and rotationally lock the outer hub 1060 and the drive body 1052. Also, the drive shaft 1026 can be rotationally locked to the drive body 1052 by the clip 1056. Thus, rotating rotational actuator 1030 rotates the outer hub 1060, which rotates both the outer shaft 1028 and the drive shaft 1026.

[0079] As shown in FIG. 3C, to improve stabilization of the drive shaft 1026 while allowing one or both of rotation and longitudinal motion, the first housing portion 1016 can include the stabilizing flange 1021 including a recess or the opening 1021 A through which a proximal end of the drive shaft 1026 can extend into or through.

[0080] To provide articulation of the lever 1024, the lever 1024 can be operably coupled to the housing 1014 via the first pin 1038. The lever 1024 can be movable about the first pin 1038 by a pivoting motion. In the example, thefirst pin 1038 is retained in the housing 1014. In other examples, the first pin 1038 may be retained by the lever 1024 or may be part of the lever 1024. As shown in FIG. 3A, the lever 1024 can be biased to a default position (FIG. 1 A) by lever return spring 1040. In the example, lever return spring 1040 can be constrained between the housing 1014 and the lever 1024. In some examples, the lever return spring 1040 can be provided as any suitable type of biasing element, such as a helical spring, an elastomeric component, an elastomeric band, or an elastomeric block arranged to bias the lever to a default position. Such a biasing element can be strained, for example by compression, extension, torsion or deflection, and elastically return to its original form, or substantially original form.

[0081] As a general overview, to transmit an input motion (e.g., input force Fl) received at the lever 1024, a first end of the coupling link 1042 can be connected to the lever 1024 via the second pin 1044. A second end of the coupling link 1042 can be connected to a first end of the drive link 1046 via the third pin 1048. As such, the coupling link 1042 can connect the lever 1024 to the drive link 1046. A second end of the drive link 1046 can be connected to the housing 1014 via the fourth pin 1050. The drive link 1046 can be formed as a yoke. For example, as shown in FIG. 3C, the drive link 1046 can include a base 1046A between the first end and the second end of the drive link 1046. A pair of spaced apart legs can extend from the base of drive link 1046 such that the ends of the legs form the second end of drive link 1046.

[0082] The illustrative forceps 1000 includes a drive shaft motion transfer assembly 1051 coupled to the housing 1014. The drive shaft motion transfer assembly 1051 can include the drive body 1052 which functions to transmit an input force Fl from the lever 1024 to the drive shaft 1026 to retract or extend the drive shaft 1026 (e.g., to open or close jaws 1012).

[0083] In addition to transmitting the input force Fl from the lever 1024 to the drive shaft 1026, in some examples, and as shown in the example forceps 1000, the drive shaft motion transfer assembly 1051, including the drive body 1052 can also transmit a rotational motion from the rotational actuator 1030, through the outer hub 1060, to both the drive shaft 1026 and the outer shaft 1028. However, not all examples of the drive body 1052 require that the drive body 1052 transmit both a longitudinal motion and a rotational motion to thedrive shaft 1026. In some examples, the drive body 1052 may only be configured to transmit one or the other of a longitudinal motion and a rotational motion through the drive body 1052 to the drive shaft 1026. For example, some medical devices may employ the extension or retraction features of forceps 1000 but without rotation; and vice versa, other medical devices may employ the rotation features without the extension or retraction features.

[0084] In the illustrative drive shaft motion transfer assembly 1051, the drive body 1052 can be positioned around the drive shaft 1026. The drive shaft 1026 can extend through a passageway 1092 in the drive body 1052 (FIG. 3B, FIG. 3C). In some examples, the passageway 1092 may be formed as a center bore, though in some examples, the passageway 1092 does not need to be central and / or does not need to be provided as a circular bore. In other examples, the passageway 1092 can be square, polygonal, irregular, or include a notch. In some examples, the passageway 1092 can include a channel. In some examples the passageway 1092 may not surround the drive shaft 1026.

[0085] The drive body 1052 can be located distal with respect to the lever 1024 and can be coupled to the lever 1024. In the example, the drive body 1052 is coupled to the lever 1024 indirectly through a series of linkages. The drive body 1052 can be connected to and receive an input force Fl from the lever 1024 via the drive link 1046 to retract or extend the drive shaft 1026 relative to the housing 1014 and the outer shaft 1028 (thereby closing or opening the jaws 1012). The drive body 1052 can be positioned within the yoke formed by the drive link 1046 to receive the input from the drive link 1046.

[0086] The drive shaft motion transfer assembly 1051 can include the forcelimiting spring 1054 and the clip 1056. The force-limiting spring 1054 can be positioned around the drive body 1052. The clip 1056 can be positioned on the drive body 1052 adjacent and end of the force-limiting spring 1054. The clip 1056 can be fixed to the drive shaft 1026. In some examples, the force-limiting spring 1054 can be any suitable type of biasing element such as an elastomeric component, an elastomeric band, or an elastomeric block that can be elastically deformed and return to its original state, or substantially original state. In some examples, clip 1056 may be inserted onto the drive shaft 1026 via one or more slots (such as vertical slots 1070A and 1070B). In some examples the clip canbe flat, while in other examples, the clip may be non-planar or have irregular, non-flat surfaces.

[0087] In some examples, the drive shaft motion transfer assembly 1051 can include the outer hub 1060 which can be connected to the drive body 1052. The outer hub 1060 can include an interior surface 1098 within which the drive body 1052, the force-limiting spring 1054, and the clip 1056 (FIG. 3A, FIG. 3C) can translate longitudinally together.

[0088] The rotational actuator 1030 can be positioned around and connected to the outer hub 1060. The rotational actuator 1030 can be rotationally constrained to the outer hub 1060 and axially constrained to the outer hub 1060. The rotational actuator 1030 can also be axially constrained with respect to the housing 1014. The nose 1062 can be connected to a distal end of the outer hub 1060, for example, by a snap fit, adhesive or threaded connection. The drive shaft 1026 and the outer shaft 1028 can extend through and out of nose 1062. In some examples the rotational actuator 1030 and / or the nose 1062 can be omitted and the outer hub 1060 can act as the rotational actuator 1030 and / or the nose 1062 to receive a rotation input directly from a user. In some examples, instead of the nose 1062 being connected to a distal end of the outer hub 1060, the nose 1062 can be connected directly to the rotational actuator 1030, for example, by a snap fit, adhesive or threaded connection.

[0089] In the example of FIG. 3 A, axial retention of the rotational actuator 1030 relative to housing 1014 can be provided by axially constraining the rotational actuator 1030 between the housing 1014 and the nose 1062. A connection between a first snap fit connector 1060C on the outer hub 1060 and a second snap fit connector 1062C on the nose 1062 can constrain the rotational actuator 1030 from moving distally. The first and second snap fit connectors are shown merely as an example, any type of snap fit connectors, or otherwise, may be provided. In this arrangement, the outer hub 1060 can be axially constrained with respect to the housing 1014 by a proximal housing flange 1060A and a distal flange 1060B of the outer hub 1060, which can be captured by surfaces of the housing 1014 that interface with the proximal housing flange 1060A and the distal flange 1060B. Furthermore, since the nose 1062 is axially constrained to the outer hub 1060, the rotational actuator 1030 can also be axially constrained to the outer hub 1060, the nose 1062 and the housing 1014by being captured between the nose 1062 and the housing 1014. In other words, the nose 1062 engages the outer hub 1060 in an axial direction to provide axial retention of both the nose 1062 as well as the rotational actuator 1030.

[0090] FIG. 4 A illustrates a partial cross-sectional view of the forceps 1000 of FIG. 1A showing the lever 1024 in a distal position (e.g., an unactuated position), in accordance with at least one example. FIG. 4B illustrates a partial cross-sectional view of the forceps 1000 of FIG. 1 A showing the lever 1024 being moved proximally (e.g., an actuated position, one of a plurality of actuated positions or user positions), in accordance with at least one example. FIG. 4C illustrates a partial cross-sectional view of the forceps 1000 of FIG. 1 A showing the lever 1024 moved further proximally (e.g., into a further actuated position, which in some examples can be a fully-actuated position, and in this case, into a force limiting or over-travel state), in accordance with at least one example. Note that a force limiting state is a position of the drive body 1052 that occurs when a force applied to the lever 1024 and transferred to the drive body 1052 exceeds a predetermined force that is based on a preload of the force-limiting spring 1054. Force limiting can occur in other actuated positions whenever the predetermined force is exceeded.

[0091] FIG. 4A, FIG. 4B, and FIG. 4C will be discussed together and provide a general illustration of how the drive body 1052, the force-limiting spring 1054, and the clip 1056 can function on the drive shaft 1026 in response to the lever 1024 providing an input to a linkage between the lever 1024 and the drive body 1052. The components of the forceps 1000 shown in FIG. 4A, FIG. 4B, and FIG. 4C include the housing 1014 having stabilizing flange 1021, the lever 1024, the drive shaft 1026, the trigger 1034, the coupling link 1042, the drive link 1046, the drive body 1052, the force-limiting spring 1054, the clip 1056, the outer hub 1060, a spool 1064, the cross pin 1066, and the trigger return spring 1068. The drive shaft 1026 can include the first horizontal slot 1069 A, the second horizontal slot 1069B, the first vertical slot 1070A, and the second vertical slot 1070B (hidden here, but viewable in FIG. 3C). The drive body 1052 includes the body portion 1072, the anchor portion 1074 (including distal spring seat 1076), the window portion 1082 (including the first window 1084A and the second window 1084B, the neck portion 1086, and the collar 1088 (including the drive surface 1090 A and the second distal spring seat 1091, alsoshown in FIG. 3C). The outer hub 1060 includes the interior surface 1098. The spool 1064 can include a proximal trigger return spring seat 1101. The spool 1064 is shown as one example of a motion transfer body designed to transmit motion received from an actuator to a shaft (e.g., received from trigger 1034 and transmitted to blade shaft 1032). In other examples a motion transfer body within this disclosure need not be spool-shaped, such as in examples where the spool 1064 does not need to be rotatable.

[0092] As shown in FIG. 4A, when the lever 1024 is in a distal position (e.g., default position, open position of jaws 1012), the drive body 1052 is positioned within the channel formed by interior surface 1098 of outer hub 1060. Most of the body portion 1072 of the drive body 1052 is within the channel of the outer hub 1060. The drive shaft 1026 is in a first position with respect to housing 1014 as it is not being pulled proximally (e.g., unactuated position, nonretracted position) by clip 1056 and is within the opening in the stabilizing flange 1021. As a result, the jaws 1012 are in an open position as shown in FIG. 1A.

[0093] As shown in FIG. 4B, when the lever 1024 is being moved proximally, the lever 1024 pulls the bottom end of the drive link 1046 in a proximal direction with respect to housing 1014 via the coupling link 1042. The drive link 1046 is connected to the drive body 1052 at the neck portion 1086 and pushes on the drive surface 1090A of the collar 1088, causing the drive body 1052 to move in a proximal direction longitudinally with respect to the housing 1014. As a result, a greater portion of the body portion 1072, including the window portion 1082, of the drive body 1052 moves out the channel of the outer hub 1060. When the drive body 1052 is pulled proximally, the force-limiting spring 1054 and the clip 1056 move along with the drive body 1052 in the same positions with respect to the drive body 1052.

[0094] In other words, the distal spring seat 1076 drives the force-limiting spring 1054, which drives the clip 1056, along with the drive body 1052. When the drive force supplied by the drive link 1046 is less than the preload force in the force-limiting spring 1054, the force-limiting spring 1054 acts like a rigid body and the ends of the force-limiting spring 1054 move together. As such, the drive body 1052 moves proximally with respect to the housing 1014 and the clip 1056 moves proximally with respect to the housing 1014. Because the clip 1056is longitudinally locked to the drive shaft 1026 at the first vertical slot 1070A and the second vertical slot 1070B, the drive shaft 1026 also moves proximally with respect to the housing 1014. As the drive shaft 1026 moves proximally (e.g., is retracted), the end effector 1002 becomes actuated. In this example, actuating the end effector 1002 includes the jaws 1012 beginning to close.

[0095] In other words, in the situation of FIG. 4B, the lever 1024 may be closed due to user input to close jaws 1012. Movement of the lever 1024 causes movement of drive body 1052. Closing lever 1024 causes the coupling link 1042 to pull drive link 1046 proximally with respect to housing 1014, which causes longitudinal translation of drive body 1052 in the proximal direction. Moving the drive body 1052 proximally causes longitudinal translation of the drive shaft 1026 in the proximal direction because the drive body 1052 and the drive shaft 1026 are connected via the clip 1056. As a result of the movement of the drive shaft 1026, a mechanism on the jaws 1012 is actuated, closing the jaws 1012. As shown in the illustrative example, while the drive link 1046 drives the drive body 1052 longitudinally, the drive body 1052 can still be free to rotate inside the yoke of the drive link 1046 and can rotate relative to the drive link 1046. However, in some examples, the rotation aspect may be omitted.

[0096] In the illustrative example, at any time during use, regardless of whether the jaws 1012 are opened or closed, the jaws 1012 can be rotated. For example, rotation of the rotational actuator 1030 rotates the outer hub 1060, which beneficially transfers rotational motion to rotate the outer shaft 1028 and the drive body 1052. Because drive body 1052 is locked (e.g., constrained) to the drive shaft 1026 via the clip 1056, the drive shaft 1026 can also rotate with the outer shaft 1028. Thus, the outer shaft 1028 and the drive shaft 1026 can be rotationally locked together (e.g., rotationally constrained) at a proximal end of forceps 1000, and as is described further herein, the outer shaft 1028 and the drive shaft 1026 can also be rotationally locked or constrained together at a distal end of the forceps 1000. In examples, outer hub 1060 can include stop flange 1904 (FIG. 2) that can engage with stop 1902 (FIG. 2) on first housing portion 1016 (FIG. 2) to limit rotation of outer shaft 1028.

[0097] Further, first horizontal slot 1069 A and second horizontal slot 1069B in drive shaft 1026 can engage and rotate cross pin 1066 at bore 1032B (FIG. 2) when the drive shaft 1026 is rotated, to rotate blade shaft 1032 and spool 1064.Thus, the drive shaft 1026 and blade assembly (1032, 1032A) can be rotationally constrained (e.g., fixed, locked together) at a proximal end of forceps 1000 via cross pin 1066 (FIG. 2, FIG. 4A). In other words, the blade assembly (1032, 1032A) can be rotationally constrained to the drive shaft 1026 at a longitudinal location along the longitudinal axis Al (FIG. IB) that is proximal of the jaws 1012 and proximal of the drive body 1052.

[0098] If actuation is complete, to return the jaws 1012 to the unactuated state of FIG. 4 A, the lever return spring 1040 can act on the lever 1024 to return (e.g., bias) the lever 1024 to the default position (e.g., distal position). Since the lever 1024 is coupled to the drive shaft 1026 by a series of linkages, the lever return spring 1040 also returns the drive shaft 1026 and thereby the jaws 1012 to a default position, which in the present example is an open position. As shown in the condition of FIG. 4C, it is possible that jaws 1012 may become stuck or caught on an anatomical feature or another medical device in the patient when the lever 1024 is being moved proximally. In such a situation, the jaws 1012 may not be able to close completely. However, the drive motion transfer assembly 1051 of forceps 1000 includes a force limiting feature that prevents the drive shaft 1026 from being retracted to the point where the jaws 1012 become damaged by the additional input force Fl from the user being transmitted to the jaws 1012. The forceps 1000 can be capable of achieving a force limiting state (e.g., an over-travel state) in instances where the lever 1024 is being moved proximally and the jaws 1012 get stuck in an open or partially open position and the user continues to apply a force to the lever 1024.

[0099] To prevent damage to the jaws 1012, the force-limiting spring 1054 can be configured to absorb excess force applied to the lever 1024 instead of transferring the excess force to the jaws. For example, the force-limiting spring 1054 can extend from a first end portion to a second end portion and can be in a preloaded state between the distal spring seat 1076 and a distal end surface of the clip 1056. The force-limiting spring 1054 can push the clip 1056 in a proximal direction such that the clip 1056 contacts and is supported by a clip support surface of the body portion 1072 adjacent a proximal end of the window portion 1082. The clip support surface can function as a proximal stop for the clip 1056. With the force-limiting spring 1054 in compression, the distal spring seat 1076 can be configured to receive a first spring force from the distal end portion of theforce-limiting spring 1054, and the clip 1056 can be configured to receive a second spring force from the proximal end portion of the force-limiting spring 1054. The drive body 1052 can include the clip support surface configured to transmit the first force to the second surface of the clip 1056 when the forcelimiting spring 1054, under a load, such as a preload, drives the clip 1056 against the clip support surface.

[0100] With continued reference to FIG. 4C, in an example of force limiting, the lever 1024 is moved to a proximal position by the user, exerting force on the drive link 1046 and pulling the bottom end of drive link 1046 further in a proximal direction, although the jaws 1012 are blocked from closing further. Consequently, the drive link 1046 exerts more force on the drive surface 1090 A of the collar 1088, moving the drive body 1052 further proximally with respect to housing 1014 and the drive body 1052 moves farther proximally out of the interior surface 1098 that forms a passageway 1098 A (FIG. 3C) of the outer hub 1060. The outer hub 1060 can be constrained from axial movement with respect to the housing 1014 by proximal housing flange 1060 A and distal flange 1060B of the outer hub 1060 which can be captured by a portion of housing 1014. As the drive body 1052 moves proximally, the distal spring seat 1076 of the anchor portion 1074 of the drive body 1052 pushes on a distal end of the force-limiting spring 1054. However, because the jaws 1012 are unable to close further, the drive shaft 1026 cannot move proximally along with the drive body 1052.Further, because the clip 1056 is locked to drive shaft 1026, the clip 1056 cannot move proximally with respect to housing 1014 either. Thus, the drive body 1052 moves proximally relative to the clip 1056 and the drive shaft 1026 by sliding (e.g., linear motion, longitudinal motion or translating) proximally relative to the clip 1056.

[0101] The clip 1056, by remaining fixed with respect to the drive shaft 1026, effectively moves distally relative to the drive body 1052 within the first window 1084A and the second window 1084B of the window portion 1082. As such, the force-limiting spring 1054 becomes more compressed between the distal spring seat 1076 and the distal end surface of the clip 1056 when the force exerted on the drive link 1046 is greater than a preload of the force-limiting spring 1054. The user can feel this force limiting feature as an increase in force on the lever 1024 due to the additional compression of the force-limiting spring1054 over the preloaded state, however, the lever 1024, which is no longer transferring motion to the drive shaft, is still movable.

[0102] In other words, the lever 1024 can be fully moved into a proximal position, moving the drive body 1052 proximally in the housing 1014 as far as the drive shaft 1026 will go. At the same time, the jaws 1012 can become locked in an open position (e.g., caught on something), preventing the drive shaft 1026 from moving even though the lever 1024 is being moved proximally. Because the drive shaft 1026 cannot move proximally in the housing 1014, the clip 1056 cannot move proximally with respect to the housing 1014. However, because the clip 1056 can slide within the window portion 1082, the drive body 1052 is able to move (e.g., slide, translate) proximally with respect to the clip 1056, changing the position of the clip 1056 within the window portion 1082. As the drive body 1052 moves with respect to the clip 1056, the force-limiting spring 1054 compresses and absorbs the force exerted on the lever 1024.Because moving the drive shaft 1026 causes the jaws 1012 to close, the ability to prevent the drive shaft 1026 from moving when the jaws 1012 are unable to close prevents the jaws 1012 from becoming damaged when a user is unaware of the jaws 1012 being stuck open and the user continues to pull the lever 1024 proximally to close the jaws 1012.

[0103] As shown in the illustrative example of FIGS. 4 A, 4B and 4C, the spool 1064 can be positioned around a proximal end of the drive shaft 1026 proximal to the drive body 1052 and can be connected to a proximal end of the blade shaft 1032 via cross pin 1066. Thus, the blade assembly (1032, 1032A) is attached to a proximal end of the drive shaft 1026 via the cross pin 1066 extending through the first horizontal slot 1069 A and the second horizontal slot 1069B. The spool 1064 can be within the housing 1014 distal to the stabilizing flange 1021. The spool 1064 can be axisymmetric and can be longitudinally movable with respect to the drive shaft 1026. In an alternate example, where the drive shaft 1026 and blade shaft 1032 do not need to rotate, the spool 1064 can be a non-spool shaped body.

[0104] The trigger 1034 can be connected to the spool 1064. A proximal end of the trigger 1034 can include one or more legs, in this example, two legs forming a yoke, that fit around and can be connected to the spool 1064. The spool 1064 can rotate relative to trigger 1034 to allow the drive shaft 1026 torotate. The trigger return spring 1068 can be a helical compression spring positioned on the drive shaft 1026 between a distal end of spool 1064 and a proximal end of drive body 1052. The trigger return spring 1068 can be assembled by loading the trigger return spring 1068 onto the drive shaft 1026 and then positioning the spool 1064 onto the drive shaft 1026 to connect trigger 1034 to the blade shaft 1032. In some examples, the trigger return spring 1068 can be any suitable biasing element such as an elastomeric component, elastomeric band or elastomeric block that can be strained and elastically return to its original form, or substantially original form.

[0105] To facilitate extension and retraction of the blade shaft 1032, the cross pin 1066 can move within the first horizontal slot 1069 A and the second horizontal slot 1069B of the drive shaft 1026. In some examples, the dimensioning of first horizontal slot 1069 A and the second horizontal slot 1069B can be such that they act as guide rails for the cross pin 1066 to control longitudinal reciprocation of spool 1064. In such an example, the spool 1064 can be guided by the drive shaft 1026. The first horizontal slot 1069A can extend into a first side of the drive shaft 1026, and the second horizontal slot 1069B can extend into a second side of the drive shaft 1026 across from or opposing the first horizontal slot 1069 A. The first horizontal slot 1069 A and the second horizontal slot 1069B are near a proximal end of the drive shaft 1026. As such, the cross pin 1066 can extend through the spool 1064, the first horizontal slot 1069A of the drive shaft 1026, the blade shaft 1032, and the second horizontal slot 1069B of the drive shaft 1026. The second arm 1034D is hidden in FIGS. 4A, 4B and 4C. The spool 1064 can include a proximal trigger return spring seat 1101 at a distal end of the spool 1064. As such, the trigger return spring 1068 can be positioned on the drive shaft 1026 between a proximal end of the drive body 1052, or the second distal spring seat 1091, and a distal end of the spool 1064, or proximal trigger return spring seat 1101. In an alternate example, a second passageway 1064 A (FIG. 2) in the spool 1064 can ride on the drive shaft 1026 and be guided for longitudinal movement along the drive shaft 1026.

[0106] As a general overview, the cutting system can operate as described in the following manner. Compressing a distal end of the trigger 1034 can move a proximal end of the trigger 1034 in a distal direction with respect to the housing1014, which can cause the spool 1064 to move distally. The spool 1064 can push against a proximal end of the trigger return spring 1068. The preload of the trigger return spring 1068 can be overcome such that trigger return spring 1068 compresses. The spool 1064, connected to the blade shaft 1032 by the cross pin 1066, can cause the blade shaft 1032 to move longitudinally in a distal direction via the cross pin 1066 traveling along, or within, the first horizontal slot 1069 A and the second horizontal slot 1069B of the drive shaft 1026, causing blade 1032A (FIG. 2) to protrude from a distal end of the drive shaft 1026. When the trigger 1034 is not compressed, the trigger return spring 1068 can expand, pushing the spool 1064 and the blade shaft 1032 in a proximal direction to a position in which the blade 1032A (FIG. 2) does not protrude from the drive shaft 1026.

[0107] FIG. 5A is an isometric view of a first end of rotational limiter 2000 of the present disclosure comprising shaft 2002 and collar 2004. FIG. 5B is an isometric view of a second end of rotational limiter 2000 of FIG. 5 A. FIG. 5C is a schematic cross-sectional view of rotational limiter 2000 of FIG. 5 A and FIG. 5B disposed within housing 1014 (FIG. 1 A) for a handpiece of a forceps 1000 (FIG. 2). FIG. 5A through FIG. 5C are discussed concurrently.

[0108] Rotational limiter 2000 is shown positioned relative to stop 2006, which can be affixed to first housing portion 1016 of FIG. 2. Rotational limiter 2000 permits shaft 2002 to be rotated greater than three-hundred- sixty degrees. Thus, rotational limiter 2000 can be connected to outer shaft 1028 (FIG. 2) to rotate jaws 1012 (FIG. 2). As such, a user can rotate jaws 1012 into any desired orientation by rotating rotational actuator 1030 in only one direction, if desired, thereby improving user experience and ergonomics and reducing user stress.

[0109] Shaft 2002 can comprise body 2008, pin 2010 and flange 2012.Body 2008 can comprise a cylindrical annulus comprising outer wall 2014, inner wall 2016 defining lumen 2018, first end 2020 and second end 2022.

[0110] Collar 2004 can comprise body 2024, tab 2026 and slot 2028. Body 2024 can comprise a cylindrical annulus comprising outer wall 2030, inner wall 2032 defining lumen 2034, first end 2036 and second end 2038.

[0111] Rotational limiter 2000 can be used in place of outer hub 1060 (FIG. 2). Specifically, shaft 2002 can be used in place of outer hub 1060 or can be incorporated into outer hub 1060. However, in other configurations, collar 2004can be configured to be used in place of hub 1060 and shaft 2002 can be configured to rotate within the hub. Likewise, stop 2006 can be used in place of or can comprise stop 1902 (FIG. 2) on first housing portion 1016 (FIG. 2).

[0112] Shaft 2002 can be connected to outer shaft 1028 and rotational actuator 1030 (FIG. 2, FIG. 5C). Rotational actuator 1030 (FIG. 2, FIG. 5C) can be connected to shaft 2002. Thus, shaft 2002 can be rotated with outer shaft 1028 via application of force to rotational actuator 1030. However, shaft 2002 can be axially constrained by connection to housing 1014 through connection to rotational actuator 1030. Collar 2004 can be configured to rotate freely between shaft 2002 and rotational actuator 1030, uncoupled to each, depending on the position of pin 2010. Axial movement of collar 2004 can be constrained by the presence of pin 2010 within slot 2028. Pin 2010 and slot 2028 can comprise an example of a pin-and-slot interface.

[0113] Rotational limiter 2000 can be configured to allow outer shaft 1028, and drive shaft 1026 located therein, to rotate about the longitudinal axis of the forceps 1000 (FIG. IB), e.g., axis Al of FIG. IB that extends in the D-P (Distal- Proximal) direction of FIG. 1 A. In particular, collar 2004 can be configured to rotate nearly three-hundred-sixty degrees so that tab 2026 can engage one side of stop 2006 to the other side of stop 2006, while shaft 2002 can rotate so that pin 2010 can engage one side of slot 2028 to the other side of slot 2028 for any given position of collar 2004. Thus, rotation of shaft 2002 can be increased beyond three-hundred-sixty degrees due to the ability of slot 2028 to float between two rotational extreme positions where tab 2026 is engaged with the opposite sides of stop 2006. However, rotational limiter 2000 still provides limits to the rotation of drive shaft 1026, to prevent damage to any components located therein, such as wires, cables, mechanical components and the like, due to engagement of pin 2010 with slot 2028 of collar 2004 and engagement of tab 2026 of collar 2004 with stop 2006, as is explained in greater detail with reference to FIG. 8 A - FIG. 8C.

[0114] FIG. 6A is an isometric view of shaft 2002 of FIG. 5 A and FIG. 5B showing pin 2010 and tab 2012. FIG. 6B is a cross-sectional view of shaft 2002 of FIG. 6 A taken at section 6B - 6B to show relative circumferential positions of pin 2010 and tab 2012. FIG. 6C is a cross-sectional view of shaft 2002 of FIG.6B taken at section 6C - 6C to show relative axial positions of pin 2010 and tab 2012. FIG. 6A - FIG. 6B are discussed concurrently.

[0115] Shaft 2002 can comprise body 2008, pin 2010 and flange 2012.Body 2008 can comprise a cylindrical annulus comprising outer wall 2014, inner wall 2016 defining lumen 2018, first end 2020 and second end 2022.

[0116] Lumen 2018 can comprise a passageway through body 2008 to allow other components to pass therethrough, such as outer shaft 1028, drive shaft 1026 and components extending therethrough, such as those shown in FIG. 1 A - FIG. 4C. As mentioned, flange 2012 is provided in the figures for illustrative purposes and can be omitted. Outer wall 2014 and inner wall 2016 are illustrated as cylindrical walls having uniform cross-sectional profiles.However, in examples, outer wall 2014 and inner wall 2016 can have other shapes, such as stepped cylindrical surfaces. As mentioned, shaft 2002 can comprise an example of outer hub 1060 (FIG. 2) and can thus have outer and inner geometries matching with the shape of outer hub 1060.

[0117] Body 2008 can comprise a component for receiving outer shaft 1028 and coupling to rotational actuator 1030. Outer shaft 1028 can be configured to extend from lumen 2018 at first end 2020. Outer shaft 1028 can be fixed to inner wall 2016 by any suitable means, such as fasteners, force fit or adhesive, to allow outer shaft 1028 to rotate with shaft 2002. Body 2008 can comprise a component for coupling to rotational actuator 1030. Rotational actuator 1030 can be attached to outer wall 2014 at one or both of a first location forward of collar 2004 and a second location aft of collar 2004. Rotational actuator 1030 can be attached to outer wall 2014 by any suitable means, such as fasteners, force fit or adhesive. In the example of FIG. 5C, rotational actuator 1030 is attached to body 2008 distal of collar 2004. Body 2008 can comprise a rigid body fabricated from metal or plastic to support outer shaft 1028 and rotational actuator 1030.

[0118] Pin 2010 can extend from body 2008 to project beyond outer wall 2014. Pin 2010 can be a separate component attached to body 2008 or can be integral with body 2008. Pin 2010 can comprise a body configured to be received within slot 2028 of collar 2004. In the illustrated example, pin 2010 comprises a cylindrical body with a flat, circular outer surface. However, pin 2010 can have any suitable shape for interacting with slot 2028. For example,pin 2010 can have a square cross-sectional profile, a hexagonal cross-sectional profile or the like. In examples, the height Hl of pin 2010 can be approximately equal to the depth DI of slot 2028, and the diameter D2 of pin 2010 can be approximately equal to the width W1 of slot 2028. As such, slop or play between pin 2010 and slot 2028 can be minimized.

[0119] FIG. 7A is an isometric view of a first end of collar 2004 of FIG. 5 A and FIG. 5B showing tab 2026 and slot 2028. FIG. 7B is an isometric view of a second end of collar 2004 of FIG. 7A showing tab 2026 and slot 2028. FIG. 7C is a cross-sectional view of collar 2004 of FIG. 7A taken at section 7C - 7C to show axial positioning of tab 2026 and slot 2028. FIG. 7D is a cross-sectional view of collar 2004 of FIG. 7 A taken at section 7D - 7D to show a circumferential extent of slot 2028. FIG. 7A - FIG. 7D are discussed concurrently.

[0120] Collar 2004 can comprise body 2024, tab 2026 and slot 2028. Body 2024 can comprise a cylindrical annulus comprising outer wall 2030, inner wall 2032 defining lumen 2034, first end 2036 and second end 2038. Slot 2028 can extend between first end wall 2040 and second end wall 2042. Body 2024 can form bridge 2044 between first end wall 2040 and second end wall 2042 of slot 2028.

[0121] Body 2024 can be configured to rotate about shaft 2002. Lumen 2034 can have a diameter that is slightly larger than the diameter of outer wall 2014 of shaft 2002. Body 2024 can be configured to hold its position about shaft 2002 but can be displaced when rotational force is applied to shaft 2002 via rotational actuator 1030. The thickness tl of body 2024 between outer wall 2030 and inner wall 2032 can provide clearance between collar 2004 and first housing portion 1016 and second housing portion 1018 of housing 1014 (FIG. 2). The length of body 2024 between first end 2036 and second end 2038 can be less than the length of body 2008 of shaft 2002 between first end 2020 and second end 2022.

[0122] Slot 2028 can extend through the thickness tl of body 2024 from outer wall 2030 to inner wall 2032 such that thickness tl is equal to depth DI. Width W1 of slot 2028 can provide axial length to accept pin 2010 (FIG. 6 A). Slot 2028 can have a circumferential arc length from first end wall 2040 to second end wall 2042. The circumferential arc length can encompass angle al.In examples, the minimum arc length of slot 2028 can be larger than the thickness of stop 2006 and tab 2026 to allow collar 2004 to make-up for the rotational loss of shaft 2002 incurred by those components, e.g., the prevention of shaft 2002 to rotate three-hundred-sixty degree caused by those components. In examples, the thickness of stop 2006 and tab 2026 allow collar to rotate approximately three-hundred-forty degrees. As shown in FIG. 8A, the thickness of stop 2006 and tab 2026 can form an arc length having angle a2, which can comprise twenty -five degrees. As such, the minimum arc length of slot 2028 can have an angle al of approximately twenty -five degrees. However, the arc length of slot 2028 can have angle al closer to three-hundred- sixty degrees. In various examples, the arc length of slot 2028 can have angle al in the range of approximately twenty-five degrees to approximately three-hundred-fifty degrees. However, smaller or larger angles can be used in other configurations depending on the the thickness o stop 2006 and tab 2026. In the illustrated example, angle al is approximately two-hundred-forty-five degrees. As explained below with reference to FIG. 8A to FIG. 8C, the arc length of slot 2028 can have angle al increased beyond three-hundred-sixty degrees by imparting a helical shape or path to slot 2028.

[0123] Tab 2026 can comprise a projection of material that extends beyond outer wall 2030 to engage stop 2006. Tab 2026 can be configured to prevent further rotation of collar 2004 when tab 2026 is rotated to engage either side of stop 2006. Tab 2026 can have a height that extends beyond outer wall 2030 a sufficient length to engage stop 2006. Tab 2026 can have a width between first end wall 2040 and second end wall 2042 sufficient to engage with stop 2006. Not all of tab 2026 need engage all of stop 2006. Tab 2026 can have a thickness to inhibit or prevent inducing stress or breakage of tab 2026. Tab 2026 can have any suitable shape for engaging with stop 2006 to prevent rotation of collar 2004. In the illustrated example, tab 2026 has a rectangular shape with the major axis of the rectangle extending along the central axis of lumen 2034 between first end wall 2040 and second end wall 2042. However, tab 2026 can have other orientations or can have other rectilinear shapes, such as square. In examples, tab 2026 can comprise projections having other shapes, such as cylindrical, dome, pin and the like.

[0124] Tab 2026 and slot 2028 can be positioned at different axial positions along collar 2004 relative to the central axis of lumen 2034 between first end wall 2040 and second end wall 2042. Tab 2026 and slot 2028 can be axially spaced apart to allow tab 2026 to engage stop 2006 and slot 2028 to engage with pin 2010 without interfering with each other. In the illustrated example, tab 2026 is located adjacent first end 2036. However, tab 2026 can be spaced from first end 2036, spaced from second end 2038 or adjacent second end 2038.

[0125] Tab 2026 and slot 2028 can be positioned at different circumferential positions along collar 2004 relative to the central axis of lumen 2034. Tab 2026 and slot 2028 can be positioned relative to each other to provide a user with an intuitive indication of the position of jaws 1012 (FIG. 1A). For example, it can be desirable for the rotational extreme positions for rotational limiter 2000 to be centered about a superior-inferior / top-bottom axis of forceps 1000, with the center of the rotational extreme positions providing jaws 1012 with an up / down opening orientation. Tab 2026 can be positioned relative to slot 2028 based on the location of stop 2006 within housing 1014. For example, if stop 2006 is positioned on the superior-most or top internal surface of housing 1014, tab 2026 can be positioned at the center of slot 2028 opposite the diametric center of bridge 2044. In the illustrated example, with stop 2006 extending from a lateral surface of housing 1014, tab 2026 can be positioned opposite an edge of slot 2028. In such configurations, bridge 2044 can be configured to be positioned at the inferior or bottom internal surface of housing 1014 when jaws 1012 (FIG.1 A) are oriented for superior-inferior opening and closing. However, in examples, tab 2026 and slot 2028 can be positioned in any relative circumferential positions on collar 2004.

[0126] FIG. 8 A is a cross-sectional view of rotational limiter 2000 of FIG. 5 A and FIG. 5B showing collar 2004 and shaft 2002 at a first rotational extreme position. FIG. 8A illustrates collar 2004 and shaft 2002 in a clock-wise most rotational position. FIG. 8A can comprise a cross-sectional view of rotational limiter 2000 looking in the distal direction. However, FIG. 8A can also represent a cross-sectional view of rotational limiter 2000 looking in the proximal direction.

[0127] Shaft 2002 can be concentrically disposed within collar 2004. Pin 2010 of shaft 2002 can be located within slot 2028 of collar 2004. In therotational extreme position of FIG. 8 A, tab 2026 can be engaged with first side 2050 of stop 2006, and pin 2010 can be engaged with first end wall 2040 of bridge 2044. As such, outer shaft 1028 (FIG. 2) extending from shaft 2002 cannot be rotated any further in the clockwise direction.

[0128] A user can apply rotational force in the counter-clockwise direction to rotational actuator 1030 (FIG. 2) to cause clockwise rotation of shaft 2002. Collar 2004 can remain supported between shaft 2002 and rotational actuator 1030 in the same position, such as by frictional engagement with housing 1014 or another feature.

[0129] FIG. 8B is a cross-sectional view of rotational limiter 2000 of FIG.5 A and FIG. 5B with collar 2004 at the first rotational extreme position and shaft 2002 rotated counter-clockwise to the opposite side of slot 2028 of collar 2004. Pin 2010 can disengage with first end wall 2040 of bridge 2044. Pin 2010 can rotate past stop 2006 and tab 2026 to second end wall 2042 of bridge 2044. As such, shaft 2002 can rotate a circumferential amount equal to the circumferential extent of slot 2028. In the illustrated example, slot 2028 has a circumferential extent of two-hundred-forty-five degrees.

[0130] FIG. 8C is a cross-sectional view of rotational limiter 2000 of FIG. 5A and FIG. 5B showing collar 2004 and shaft 2002 rotated counter-clockwise to a second rotational extreme position. After pin 2010 engages with second end wall 2042, pin 2010 can push against bridge 2044 to push collar 2004 counterclockwise until tab 2026 engages second side 2052 of stop 2006. In the illustrated example, collar 2004 can rotate approximately three-hundred-forty degrees. As such, shaft 2002 and outer shaft 1028 extending therefrom can rotate a total of five-hundred-eighty-five degrees.

[0131] FIG. 9A is an isometric view of a first end of shaft 3000 of the present disclosure including slot 3002. FIG. 9B is an isometric view of a second end of shaft 3000 of FIG. 9A showing a backside of slot 3002. FIG. 9C is a schematic cross-sectional view of shaft 3000 of FIG. 9A and FIG. 9B located within housing 3004 of a surgical instrument having moveable stop 3006. FIG. 9 A - FIG. 9C are discussed concurrently.

[0132] Shaft 3000 can comprise body 3008 having slot 3002. Body 3008 can comprise a cylindrical annulus comprising outer wall 3010, inner wall 3012 defining lumen 3014, first end 3016 and second end 3018. Slot 3002 can have ahelical, corkscrew or spiral shape to allow shaft 3000 to rotate more than three- hundred-sixty degrees. As such, first end wall 3020 and second end wall 3022 of slot 3002 can be axially spaced apart along shaft 3000.

[0133] Lumen 3014 can comprise a passageway through body 3008 to allow other components to pass therethrough, such as drive shaft 1026 and outer shaft 1028. Outer wall 3010 and inner wall 3012 are illustrated as cylindrical walls having uniform cross-sectional profiles. However, in examples, outer wall 3010 and inner wall 3012 can have other shapes, such as stepped cylindrical surfaces. Shaft 3000 can comprise an example of outer hub 1060 (FIG. 2) and can thus have outer and inner geometries matching with the shape of outer hub 1060.

[0134] Body 3008 can comprise a component for receiving outer shaft 1028 and drive body 1052. Outer shaft 1028 can be configured to extend from lumen 3014 at first end 3016. Outer shaft 1028 can be fixed to inner wall 3012 by any suitable means, such as fasteners, force fit or adhesive, to allow outer shaft 1028 to rotate with shaft 3000. Body 3008 can comprise a component for coupling to rotational actuator 1030. Rotational actuator 1030 can be attached to outer wall 3010 at one or both of a first location forward of slot 3002 and a second location aft of slot 3002. Rotational actuator 1030 (FIG. 9C) can be attached to outer wall 3010 by any suitable means, such as fasteners, force fit or adhesive. Body 3008 can comprise a rigid body fabricated from metal or plastic to support outer shaft 1028 and rotational actuator 1030.

[0135] Slot 3002 can extend from first end wall 3020 to second end wall 3022. Slot 3002 can have first sidewall 3024 and second sidewall 3026 that follow helical paths through body 3008 between first end wall 3020 and second end wall 3022.

[0136] Slot 3002 can extend through the thickness of body 3008 from outer wall 3010 to inner wall 3012. Slot 3002 can be axially long enough to accept pin 3036. Slot 3002 can have a helical length from first end wall 3020 to second end wall 3022. In examples, the length of slot 3002 can be long enough to allow shaft 3000 to rotate greater than three-hundred-sixty degrees.

[0137] Moveable stop 3006 can comprise slide mechanism 3034 and pin 3036. Pin 3036 can comprise a body configured to be received within slot 3002. Pin 3036 and slot 3002 can comprise an example of a pin-and-slot interface. Pin 3036 can extend from housing 1014 into slot 3002. Pin 3036 can extend throughouter wall 3010. In the illustrated example, pin 3036 comprises a cylindrical body with flat, circular outer surfaces. However, pin 3036 can have any suitable shape for interacting with slot 3002. For example, pin 3036 can have a square cross-sectional profile, a hexagonal cross-sectional profile or the like. In examples, the height of pin 3036 can be approximately equal to the depth of slot 3002, and the diameter of pin 3036 can be approximately equal to the width of slot 3002. As such, slop or play between pin 3036 and slot 3002 can be minimized.

[0138] As shown in FIG. 9C, shaft 3000 can be mounted in housing 3004, which can comprise housing 1014 of FIG. 1A. Outer shaft 1028 can extend from shaft 3000 out of the distal end of housing 3004. Actuator knob 3030 can be coupled to shaft 3000. Outer shaft 1028 can be configured for rotation within housing 3004 as described herein. In examples, outer shaft 1028 can be mounted within housing 3004 via ring bearing 3032. Ring bearing 3032 can be configured to hold shaft 3000 in a fixed position axially but can allow for rotation of shaft 3000.

[0139] Actuator knob 3030 can be coupled to shaft 3000 and can be accessible from the exterior of housing 3004 to allow a user to rotate actuator knob 3030 and therefore shaft 3000.

[0140] Moveable stop 3006 can be mounted within housing 3004 via slide mechanism 3034. Slide mechanism 3034 can allow pin 3036 to translate axially within housing 3004 but can prevent rotational movement of pin 3036.

[0141] Actuator knob 3030 can be rotated by a user to cause shaft 3000 to rotate within housing 3004. Rotation of shaft 3000 can cause slot 3002 to push against pin 3036, which can cause pin 3036 to be pushed backward (proximally) or forward (distally) depending on the direction that actuator knob 3030. Thus, as shaft 3000 is rotated, the helical shape of slot 3002 does not generate force that would tend to push shaft 3000 backward or forward. Instead, pin 3036 can move backward or forward on slide mechanism 3034. Slide mechanism can comprise a slot having rails that can ride within complimentary grooves on pin 3036. The rails and grooves can prevent pin 3036 from moving radially out of slide mechanism 3034 but can allow pin 3036 to slide or translate in the axial direction. As such, actuator knob 3030 can be rotated in clockwise or counterclockwise directions until pin 3036 reaches first end wall 3020 or second endwall 3022 of slot 3002. Thus, shaft 3000, as well as outer shaft 1028, can be rotated more than three-hundred sixty degrees, while still providing rotational limits to prevent damage to components within outer shaft 1028.

[0142] In additional example, shaft 3000 can be configured to translate axially about outer shaft 1028 and pin 3036 can be attached to housing 1014 in a fixed manner. Thus, outer shaft 1028 can be axially fixed and rotationally enabled, shaft 3000 with helical slot 3002 can be rotationally fixed to outer shaft 1028 but can slide axially relative to outer shaft 1028, and pin 3036 can remain circumferentially and axially fixed in place. Actuator knob 3030 can be connected directly to outer shaft 1028. Rotational input applied to actuator knob 3030 can apply rotation to outer shaft 1028, shaft 3000 can rotate with outer shaft 1028, while being pushed axially backward or forward by the pin. Once pin 3036 reaches the end of slot 3002, further rotation and translation of shaft 3000 can be arrested, thereby also stopping rotation of outer shaft 1028. In examples, flanges 3038 extending from inner wall 3012 can be configured to ride in an axial slot within the outer surface of outer shaft 1028. Compression springs can be used to apply axial positioning to the helically slotted shaft and coils springs can be used to apply circumferential positioning to the helically slotted shaft.

[0143] Rotational limiter 2000 of FIG. 5A - 8C and shaft 3000 of FIG. 9A - FIG. 9C can allow outer shaft 1028 (FIG. 2) to rotate more than hub 1060 allows outer shaft 1028 to rotate using only flange 1904 and stop 1902 (FIG. 2). As described herein, such configurations can allow a user of forceps 1000 to more directly rotate outer shaft 1028 to a desired orientation without interference from a rotational stop. Thus, the user can experience reduced times for performing interventional procedural times and reduced repetitive stress in performing such procedures. However, rotational limiter 2000 and shaft 3000 still provide limits to the rotation of outer shaft 1028 so that outer shaft 1028 can only move over a finite rotational path to prevent inflicting damage to components within outer shaft 1028, such as wiring. The finite rotational path of rotational limiter 2000 can comprise a two-stage circumferential path wherein two circumferential paths less than three-hundred- sixty degrees can be added to provide a circumferential rotational path in a single plane that is greater than three-hundred-sixty degrees. The finite rotational path of shaft 3000 can extend over an axial length toprovide a rotational path that is over three-hundred-sixty degrees, such as by the use of a helical slot.EXAMPLES

[0144] Example l is a medical instrument comprising: a housing; a working shaft extending from the housing, the working shaft including: a rotation mechanism located proximate a proximal portion of the working shaft to facilitate rotation of the working shaft relative to the housing; and an intervention device proximate a distal portion of the working shaft; and a rotation limiter configured to allow the working shaft to rotate relative to the housing, wherein the rotation limiter allows the working shaft to rotate relative to the housing over a finite rotational path that is more than one-hundred-sixty degrees.

[0145] In Example 2, the subject matter of Example 1 optionally includes wherein the housing comprises a projection to engage with the rotation limiter to provide an interface with the rotation limiter.

[0146] In Example 3, the subject matter of Example 2 optionally includes wherein the rotation limiter comprises a surface to engage the projection to arrest rotation of the working shaft.

[0147] In Example 4, the subject matter of Example 3 optionally includes wherein the rotation mechanism comprises a hub connected to the proximal portion of the working shaft that is rotatable relative to the housing.

[0148] In Example 5, the subject matter of Example 4 optionally includes wherein the rotation limiter comprises: a pin extending from the hub; and a collar rotatably mounted to the hub, the collar comprising: an inner surface to receive the hub; an outer surface having a flange defining the surface; and a slot to receive the pin.

[0149] In Example 6, the subject matter of Example 5 optionally includes wherein: the collar is configured to rotate to allow the flange to engage opposite sides of the projection; and the hub is configured to rotate within the collar so that the pin can engage opposite ends of the slot.

[0150] In Example 7, the subject matter of any one or more of Examples 5-6 optionally include wherein the slot extends over an arc length having an angle of approximately two-hundred-forty-five degrees.

[0151] In Example 8, the subject matter of any one or more of Examples 3-7 optionally include wherein the rotation limiter comprises a slot extending along the working shaft, wherein the slot extends along a helical path over an axial length of the working shaft.

[0152] In Example 9, the subject matter of Example 8 optionally includes wherein the surface of the rotation limiter comprises a pin extending from the housing, wherein the pin is configured to translate along a track extending over the axial length.

[0153] In Example 10, the subject matter of any one or more of Examples 1-9 optionally include wherein: the intervention device comprises a forceps; and the working shaft includes: an internal mechanism for actuating the forceps; and wiring for delivering electrical energy to the forceps.

[0154] Example 11 is a rotation limiting assembly for a forceps, the rotation limiting assembly comprising: a hub configured to receive a shaft of the forceps so that the shaft and the hub can rotate about an axis within a housing of the forceps; and a pin-and-slot interface configured to limit rotation between the hub and the housing, the pin-and-slot interface allowing the hub to rotate over-three- hundred-sixty degrees before limiting rotation.

[0155] In Example 12, the subject matter of Example 11 optionally includes a collar surrounding the hub to rotate freely about the hub, the collar including a stop feature to engage a complementary feature of the housing to prevent rotation of the collar; wherein the pin-and-slot interface allows rotation of the collar to be limited by the complementary feature and rotation of the hub to be limited by the collar independent of the complementary feature.

[0156] In Example 13, the subject matter of Example 12 optionally includes wherein: a slot of the pin-and-slot interface extends over a circumferential arc length defining an angle in a range of approximately twenty-five degrees to approximately three-hundred-forty degrees.

[0157] In Example 14, the subject matter of Example 13 optionally includes wherein the angle is approximately two-hundred-forty -five degrees.

[0158] In Example 15, the subject matter of any one or more of Examples 13- 14 optionally include wherein: the slot of the pin-and-slot interface is located on the collar; and a pin of the pin-and-slot interface is located on the shaft.

[0159] In Example 16, the subject matter of any one or more of Examples 13-15 optionally include wherein: the slot of the pin-and-slot interface is located on the shaft; and a pin of the pin-and-slot interface is located on the collar.

[0160] In Example 17, the subject matter of any one or more of Examples 12-16 optionally include wherein the stop feature of the collar comprises a flange.

[0161] In Example 18, the subject matter of any one or more of Examples 11-17 optionally include wherein the pin-and-slot interface comprises: a slot extending along the hub; and a pin connectable to a housing of the forceps.

[0162] In Example 19, the subject matter of Example 18 optionally includes wherein the slot extends along a helical path.

[0163] In Example 20, the subject matter of any one or more of Examples 18- 19 optionally include wherein the pin is configured to translate along the housing.NOTES

[0164] While illustrative examples of a medical device are shown and described in this disclosure with respect to a forceps, the features can be used in other medical devices besides forceps for controlling end effectors used in diagnosis, treatment or surgery. Any representation of a forceps or description thereto is shown primarily for illustrative purposes to disclose features of various examples.

[0165] The forceps illustrated in the examples can be an electrosurgical device, however, the forceps may be any type of medical device that facilitates mechanical and / or electrical actuation of one or more end effectors or other elements arranged distal from the handpiece having one or more actuation systems. The actuation systems described, which can extend, retract or rotate one or more shafts to produce this result, can be used to effect actions in other medical devices (e.g., medical instruments).

[0166] The directional descriptors described herein are used with their normal and customary use in the art. For example, proximal, distal, lateral, up, down, top and bottom may be used to describe the apparatus with the longitudinal axis arranged parallel to a ground with the device in an upright position. The proximal direction refers to a direction towards the user end of theapparatus, and the distal direction represents a direction towards the patient end of the apparatus.

[0167] Relative terms described herein, such as, “about” or “substantially” may be used to indicate a possible variation of ±10% in a stated numeric value, or a manufacturing variation.

[0168] As described throughout this disclosure, components and assemblies can be operably connected to each other and interact with one another in a manner that provides improved actuation, a more compact and simpler design, lower cost, and better user satisfaction than traditional medical devices.

[0169] The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventor also contemplates examples in which only those elements shown or described are provided. Moreover, the present inventor also contemplates examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

[0170] In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0171] In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls. In this document, the terms “including” and “in which” are used as the plain- English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim.

[0172] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

CLAIMSWhat is claimed is:

1. A medical instrument comprising: a housing; a working shaft extending from the housing, the working shaft including: a rotation mechanism located proximate a proximal portion of the working shaft to facilitate rotation of the working shaft relative to the housing; and an intervention device proximate a distal portion of the working shaft; and a rotation limiter configured to allow the working shaft to rotate relative to the housing, wherein the rotation limiter allows the working shaft to rotate relative to the housing over a finite rotational path that is more than one-hundred-sixty degrees.

2. The medical instrument of claim 1, wherein the housing comprises a projection to engage with the rotation limiter to provide an interface with the rotation limiter.

3. The medical instrument of claim 2, wherein the rotation limiter comprises a surface to engage the projection to arrest rotation of the working shaft.

4. The medical instrument of claim 3, wherein the rotation mechanism comprises a hub connected to the proximal portion of the working shaft that is rotatable relative to the housing.

5. The medical instrument of claim 4, wherein the rotation limiter comprises: a pin extending from the hub; and a collar rotatably mounted to the hub, the collar comprising: an inner surface to receive the hub; an outer surface having a flange defining the surface; and a slot to receive the pin.

6. The medical instrument of claim 5, wherein: the collar is configured to rotate to allow the flange to engage opposite sides of the projection; and the hub is configured to rotate within the collar so that the pin can engage opposite ends of the slot.

7. The medical instrument of claim 5, wherein the slot extends over an arc length having an angle of approximately two-hundred-forty-five degrees.

8. The medical instrument of claim 3, wherein the rotation limiter comprises a slot extending along the working shaft, wherein the slot extends along a helical path over an axial length of the working shaft.

9. The medical instrument of claim 8, wherein the surface of the rotation limiter comprises a pin extending from the housing, wherein the pin is configured to translate along a track extending over the axial length.

10. The medical instrument of claim 1, wherein: the intervention device comprises a forceps; and the working shaft includes: an internal mechanism for actuating the forceps; and wiring for delivering electrical energy to the forceps.

11. A rotation limiting assembly for a forceps, the rotation limiting assembly comprising: a hub configured to receive a shaft of the forceps so that the shaft and the hub can rotate about an axis within a housing of the forceps; and a pin-and-slot interface configured to limit rotation between the hub and the housing, the pin-and-slot interface allowing the hub to rotate over-three-hundred-sixty degrees before limiting rotation.

12. The rotation limiting assembly of claim 11, further comprising a collar surrounding the hub to rotate freely about the hub, the collar including a stopfeature to engage a complementary feature of the housing to prevent rotation of the collar; wherein the pin-and-slot interface allows rotation of the collar to be limited by the complementary feature and rotation of the hub to be limited by the collar independent of the complementary feature.

13. The rotation limiting assembly of claim 12, wherein: a slot of the pin-and-slot interface extends over a circumferential arc length defining an angle in a range of approximately twenty -five degrees to approximately three-hundred-forty degrees.

14. The rotation limiting assembly of claim 13, wherein the angle is approximately two-hundred-forty-five degrees.

15. The rotation limiting assembly of claim 13, wherein: the slot of the pin-and-slot interface is located on the collar; and a pin of the pin-and-slot interface is located on the shaft.

16. The rotation limiting assembly of claim 13, wherein: the slot of the pin-and-slot interface is located on the shaft; and a pin of the pin-and-slot interface is located on the collar.

17. The rotation limiting assembly of claim 12, wherein the stop feature of the collar comprises a flange.

18. The rotation limiting assembly of claim 11, wherein the pin-and-slot interface comprises: a slot extending along the hub; and a pin connectable to a housing of the forceps.

19. The rotation limiting assembly of claim 18, wherein the slot extends along a helical path.

20. The rotation limiting assembly of claim 18, wherein the pin is configured to translate along the housing.

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