Articulating knife actuator for electrosurgical instruments

Abstract

A knife drive assembly capable of advancing and retracting a knife along a knife blade path defined by the jaws of a surgical instrument, regardless of continuous rotation of the shaft and jaws. The assembly includes a housing having a shaft extending along a longitudinal axis and supporting a pair of jaws that define the knife path, and a lever pivotally mounted to the housing and extending into the housing. A knife actuator is coupled at a first end to the lever and at a second end to a bearing sleeve. A drive shaft is fixed to the bearing sleeve and extends into the shaft to move the knife along the knife path in response to movement of the bearing sleeve. As a result, the main shaft and drive shaft may be rotated 360 degrees by movement of the lever, which can move the knife.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 087,530, filed October 5, 2020, which is hereby incorporated by reference in its entirety.

[0002] 1. Field of the Invention The present invention relates to surgical instruments and, more particularly, to a vessel sealer having an articulating knife actuator for advancing a knife into the jaws of the vessel sealer. [Background technology]

[0003] 2. Description of Related Art An electrosurgical vessel sealer is a surgical instrument used for occlusion of blood vessels and stopping bleeding during surgical procedures. The electrodes of the vessel sealer are held by a pair of opposing jaws that are attached to the end of an elongated shaft and interconnected to an electrosurgical generator that can selectively supply radio frequency (RF) energy to the electrodes. A user may close the jaws around the vessel to be sealed by squeezing a lever associated with the handle assembly. The vessel may then be sealed by supplying RF energy to the clamped vessel, and the vessel may be severed by extending a knife blade along a track formed in the jaws. Conventional approaches to driving knife blades do not allow for continuous rotation of the shaft. Thus, there is a need for an approach that can allow the shaft of the instrument to rotate 360 ​​degrees while still allowing the user to manipulate the knife blade even after the shaft is placed in the desired position. Summary of the Invention

[0004] The present invention is a knife drive assembly capable of advancing and retracting a knife along a knife blade path defined by the jaws of a surgical instrument independent of continuous rotation of the shaft and jaws. In a first embodiment, a surgical instrument according to the present invention comprises a housing having a shaft extending along a longitudinal axis and supporting a pair of jaws defining a knife path, and a lever pivotally mounted to the housing and extending within the housing. A knife actuator is coupled to the lever at a first end and extends longitudinally within the housing to a second end. A bearing sleeve is coupled to the second end of the knife actuator. A drive shaft is secured to the bearing sleeve for moving the knife along the knife path in response to movement of the bearing sleeve. The lever may include a bearing cup that mechanically couples the lever to the knife actuator. The second end of the knife actuator may include a fork extending around the bearing sleeve. The bearing sleeve may include a pair of bearing members positioned on either side of the fork of the knife actuator. The shaft and the drive shaft may be rotatable 360 ​​degrees. Pivotal movement of the level between the first and second positions causes the knife actuator to drive the bearing sleeve from the retracted position to the extended position. The bearing sleeve may be biased toward the first position to retract the knife blade after use.

[0005] In another embodiment, the invention is a method of making a surgical device having a knife blade that can be retracted and extended within jaws that are free to rotate continuously. The method includes providing a lever pivotally mounted to and extending partially within a housing. The lever is coupled to a first end of a knife actuator that extends longitudinally within the housing. A second end of the knife actuator is coupled to a bearing sleeve that extends about a rotatable shaft of the surgical device. The knife blade is secured to the bearing sleeve such that movement of the lever from a first position to a second position advances the knife actuator distally within the housing and drives the bearing sleeve along the shaft to move the knife blade from a retracted position to an extended position within the jaws.

[0006] The present invention will be more fully understood and appreciated from a reading of the following detailed description in conjunction with the accompanying drawings, in which: [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of an electrosurgical system having an electrosurgical instrument with a knife actuation assembly in accordance with the present invention. [Diagram 2] FIG. 2 is a perspective view of a jaw of an electrosurgical instrument capable of supporting a knife driven by a knife actuation assembly according to the present invention. [Diagram 3] FIG. 3 is a schematic diagram of a lower jaw illustrating movement of a knife blade from a retracted position to an extended position in response to movement of a knife actuating assembly in accordance with the present invention. [Figure 4] FIG. 4 is a perspective view of a knife actuation assembly according to the present invention. [Diagram 5] FIG. 5 is a schematic diagram illustrating movement of a knife actuating assembly according to the present invention from a first position to a second position in response to manual movement of a lever. [Figure 6] FIG. 6 is a perspective view of a lever and knife actuator according to the present invention. [Figure 7]FIG. 7 is a schematic diagram of a lever and knife actuator connection according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Referring to the figures, in which like numerals refer to like parts throughout, there is seen in Figure 1 an electrosurgical system 10 including a vessel sealer 12 having a pair of electrically conductive opposing jaws 14 interconnected to an electrosurgical generator 16 capable of supplying RF energy to electrodes of the jaws 14 for desiccation of a blood vessel trapped between the jaws 14. As is known in the art, the jaws 14 are pivotally mounted on a longitudinally extending shaft 15 of the vessel sealer 12 for movement between open and closed positions in response to a user manipulation of a lever 18 extending from the vessel sealer 12.

[0009] 2, the jaw 14 is comprised of two opposing jaw members 20 and 22. The jaw members 20 and 22 support inner conductive surfaces 24 and 26 that are electrically isolated from the remainder of the jaw 14 and the sealer 12, and interconnected to the electrosurgical generator 16. The inner conductive surfaces 24 and 26 have tracks 28 and 30, respectively, formed therethrough, such that when the jaw members 20 and 22 are closed, the tracks 28 and 30 align to define a knife path that intersects the area of ​​the jaw members 20 and 22 where tissue is desiccated between the jaws 14 when energized.

[0010] 3, the knife blade 34 is aligned with and positioned within the knife path defined by tracks 28 and 30 and may be selectively extended through and retracted from the knife path to cut any tissue trapped in the jaws 14, for example, by a user manipulating a lever 40 pivotally mounted to a housing 42 of the sealer 12. As described herein, the knife blade 34 may be moved between the retracted and extended positions regardless of the orientation of the jaws. For example, a user of the vessel sealer 12 may rotate the shaft 15 360 degrees to position the jaws 14 in a particular orientation for a procedure, without compromising the ability of the knife blade 34 to be driven into the extended position to cut any tissue captured in the jaws 14.

[0011] 4, the lever 40 is pivotally mounted to the housing 42 and extends into the housing 42 terminating in a bearing cup 44. The bearing cup 44 provides a mechanical connection to a first end 36 of a knife actuator 46 that engages the cup 44 and extends longitudinally along the inside of the housing 42 to a second end to form a fork 48 having two arms that extend around and are mechanically linked to a bearing sleeve 50. The bearing sleeve 50 includes opposed bearing members 52 and 54 that are positioned longitudinally around the fork 48 such that movement of the knife actuator 46 can drive the bearing sleeve 50 longitudinally. The bearing sleeve 50 is secured to the shaft 15 for rotation therewith. For example, the bearing sleeve 50 may have an internal shape that corresponds to an external shape of the shaft 15. The bearing sleeve 50 is secured to and longitudinally movable relative to a drive shaft 56 that is positioned within and extends within the shaft 15 of the vessel sealer 12. For example, as seen in FIG. 5 , shaft 15 includes longitudinal slot 38, allowing bearing sleeve 50 to be secured to drive shaft 56 while allowing bearing sleeve 50 to translate longitudinally along shaft 15. Drive shaft 56 is secured to knife blade 34 such that longitudinal movement of bearing sleeve 50 along shaft 15 urges drive shaft 56 longitudinally, thereby moving knife 34 along the knife path of jaw 14. Shaft 15 is mounted in housing 42 for continuous longitudinal rotation thereabout, and jaw 14 is fixed relative to shaft 15, thereby allowing a user to position jaw 14 in a desired position by rotating shaft 15. Bearing sleeve 50 can be translated longitudinally on drive shaft 56 regardless of the rotational positioning of bearing sleeve 50 along shaft 15.

[0012] 5, proximal pivotal movement of the exposed end of lever 40 toward housing 42 activates knife actuator 46 to push bearing sleeve 50 distally, thereby causing shaft 56 to drive a knife blade coupled thereto longitudinally along the knife path of jaw 14 to cut any tissue trapped therein. Thus, lever 40 is movable from a first position to a second position, causing knife actuator 46 to drive bearing sleeve 50 distally along shaft 15, which moves knife blade from the retracted position to the extended position to cut tissue trapped in jaw 14. As is known in the art, bearing sleeve 50 may be biased to return to the retracted position in the absence of a user force applied to lever 40, thereby retracting the knife from the extended position of the knife path to the retracted position. Alternatively, a user may manually move lever 40 back to the first position to retract knife 34 from the knife path.

[0013] 6, each arm of fork 48 has a bearing surface 60 and 62 extending proximally and distally to engage bearing members 52 and 54, respectively. Bearing surfaces 60 and 62 allow for the transfer of forces to and from bearing sleeve 50 regardless of the rotational positioning of sleeve 50. Bearing surfaces 60 and 62 are also for transferring forces to and from bearing sleeve 50 when knife actuator 46 is actuated by lever 40, since the connection between lever 40 and knife actuator 46 may result in some pivoting of knife actuator 46 due to the mechanical connection to bearing cup 44. The combination of lever 40, knife actuator 46, and bearing sleeve 50 allows pivoting of lever 40 to translate into longitudinal movement of knife actuator 46, and therefore of the bearing sleeve. Additionally, the connection between fork 48 and bearing sleeve 50 allows for longitudinal movement of knife actuator 46 to drive bearing sleeve 50 to actuate the knife while simultaneously allowing shaft 15 to rotate 360 ​​degrees without losing the ability to operate the knife.

[0014] 7, the bearing cup 44 supports a tab 70 having an aperture 72 formed therethrough. The first end 36 of the knife actuator 46 is split and includes a post 74 extending transversely to the longitudinal axis of the knife actuator 46 for engaging the aperture 72. The tab 70 of the cup 44 and the post 74 of the knife actuator 46 form a rotational joint that enables the lever 40 to pivot to drive the knife actuator 46 longitudinally within the housing 42 of the vessel sealer 12, thereby manipulating the knife 34.

Claims

1. 1. A surgical instrument comprising: a housing having a shaft extending along a longitudinal axis and supporting a pair of jaws defining a knife path; a lever pivotally mounted to and extending into the housing; a knife actuator coupled to the lever at a first end and extending longitudinally within the housing toward a second end; a sleeve coupled to the second end of the knife actuator; a knife positioned in the knife path and coupled to the sleeve, the knife moving with the sleeve in response to movement of the lever and the knife actuator; Equipped with the sleeve is attached to the shaft so as to be able to rotate together with the shaft and to move relative to the shaft in the longitudinal direction of the shaft; the second end has two arms that extend around the sleeve such that a portion of the sleeve is located between the two arms, the two arms being mechanically coupled to the sleeve; the sleeve has a pair of flanges that engage with the two arms on both sides in the longitudinal direction, A surgical instrument, wherein the two arms and the sleeve are connected such that the sleeve can move in the longitudinal direction relative to the shaft regardless of the rotational position of the sleeve.

2. The surgical instrument of claim 1 , wherein the lever is mechanically coupled to the knife actuator and forms a rotational joint with the knife actuator.

3. The surgical instrument of claim 1 , wherein the shaft is rotatable 360 ​​degrees.

4. The surgical instrument of claim 1 , wherein pivotal movement of the lever from a first position to a second position causes the knife actuator to drive the sleeve distally.

5. The surgical instrument of claim 4 , wherein the sleeve is proximally biased.

6. 3. The surgical instrument of claim 2, wherein the rotary joint is comprised of a tab extending from an end of the lever, an aperture formed through the tab, and a protrusion on the first end of the knife actuator that engages with the aperture in the tab.

7. 1. A method of making a surgical device having a knife that can be retracted and extended within a jaw that is rotatable 360 ​​degrees, comprising: providing a lever pivotally mounted to the housing and extending partially therethrough; connecting the lever to a first end of a knife actuator extending longitudinally within the housing; a sleeve is attached to the shaft so as to be able to rotate integrally with the shaft supporting the jaw and capable of rotating 360 degrees, and to be able to move in the longitudinal direction of the shaft relative to the shaft; two arms provided at a second end of the knife actuator extend around the sleeve with a portion of the sleeve positioned between the two arms, and a pair of flanges are provided on the sleeve to engage with the two arms on either side of the longitudinal direction; mechanically coupling the two arms to the sleeve to allow movement of the sleeve in the longitudinal direction relative to the shaft regardless of the rotational position of the sleeve; securing the knife to a drive shaft positioned within and extending therethrough and securing the sleeve to the drive shaft such that movement of the lever from a first position to a second position distally advances the knife actuator within the housing to drive the sleeve along the shaft to move the knife from a retracted position to an extended position within the jaws; A method comprising:

8. The method of claim 7 , wherein the lever is mechanically coupled to the knife actuator and forms a rotational joint with the knife actuator.

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