Bipolar end effector apparatus for a surgical instrument
View Patent ↗An end effector apparatus for a surgical instrument is disclosed including a housing having a first jaw mounted on a revolute joint and providing a first electrical conduction path between the housing and the first jaw. A second jaw is mounted on a revolute joint within the housing and is insulated from the housing, the jaws each having a manipulating portion and a lever arm. A yoke is received within the housing and mechanically coupled to the lever arms and to a control link and is moveable in response to movements of the control link to cause opening and closing of the jaws, the yoke being electrically insulated from the housing and the first jaw. A second electrical conduction path is provided between the control link and the second jaw. The electrical conduction paths facilitate conduction of an electrocauterization current through tissue grasped between the jaws.
1. An end effector apparatus for a surgical instrument, the apparatus comprising:
a housing including an outer clevis;
a first jaw mounted on a revolute joint within the housing so as to provide a first electrical conduction path between the housing and the first jaw, the first jaw having a manipulating portion extending forwardly and a lever arm projecting rearwardly from the revolute joint mounting the first jaw;
a second jaw mounted on a revolute joint within the housing and electrically insulated from the housing, the second jaw having a manipulating portion extending forwardly from and a lever arm projecting rearwardly from the revolute joint mounting the second jaw;
a yoke received within the housing and mechanically coupled to the respective lever arms of the first and second jaws and to a control link, the yoke being moveable with respect to the housing in response to movements of the control link when actuated by the surgical instrument, the movement of the yoke being operable to cause opening and closing movements of the first and second jaws about the respective revolute joints, the yoke being electrically insulated from the housing and the first jaw, the yoke including:
an inner clevis having arms configured to receive the respective lever arms of the first and second jaws; and
an electrically insulating material; and
a second electrical conduction path between the control link and the second jaw, the first and second electrical conduction paths facilitating conduction of an electrocauterization current through tissue grasped between the first and second jaws, wherein the control link extends through the yoke and has a portion in sliding contact with the second jaw for completing the second electrical conduction path.
2. The apparatus of claim 1 wherein the revolute joint includes a first revolute joint and a second revolute joint, and wherein the first jaw is mounted on the first revolute joint within the housing and the second jaw is mounted on the second revolute joint within the housing.
3. The apparatus of claim 1 wherein the first jaw and the second jaw are mounted on a common revolute joint within the housing.
4. The apparatus of claim 3 wherein the common revolute joint includes a pivot pin extending between a pair of arms associated with the outer clevis.
5. The apparatus of claim 4 wherein the yoke comprises an inner clevis having arms configured to receive the respective lever arms of the first and second jaws.
6. The apparatus of claim 4 wherein the second jaw is mounted on an insulating spacer received on the pivot pin.
7. The apparatus of claim 1 further comprising a torque tube coupled to the housing, the torque tube being operable to cause rotation of the housing when actuated by the surgical instrument and wherein the torque tube is in electrical connection with the housing for carrying the electrocauterization current.
8. The apparatus of claim 7 wherein the control link is received within a bore of the torque tube and further comprising an electrically insulating sheath between the control link and the torque tube and wherein the control link and torque tube are operable to connect to respective poles of a bipolar electrocautery current generator.
9. The apparatus of claim 8 wherein the torque tube, insulating sheath, and control link are configured to flex within an articulated tool positioner to permit dexterous movement of the end effector apparatus.
10. The apparatus of claim 1 wherein the housing comprises an electrically conductive material and further comprising an electrically conductive washer disposed on the revolute joint between the first jaw and the housing for providing the first electrical conduction path.
11. The apparatus of claim 1 wherein the portion of the control link in sliding contact with the second jaw comprises a conductive tab having a surface that contacts the second jaw.
12. The apparatus of claim 1 wherein the lever arms associated with the first and second jaws each comprise a slot and wherein the yoke comprises a pin slidingly received within the respective slots for providing the mechanical coupling between the yoke and the lever arms.
13. The apparatus of claim 12 wherein the slot comprises an arcuate slot.
14. The apparatus of claim 12 wherein the pin comprises:
an insulated portion received within the slot in the lever arm of the first jaw; and
a conductive pin portion received within the slot in the lever arm of the second jaw for completing the second electrical conduction path between the control link and the second jaw.
15. The apparatus of claim 1 wherein the housing comprises an insulating material and wherein the first electrical conduction path between the housing and the first jaw is provided by a conductor running through the housing and having a portion in sliding contact with the first jaw.
16. The apparatus of claim 1 further comprising a linkage extending between the lever arm associated with at least one of the first and second jaws and the yoke for providing the mechanical coupling between the yoke and the lever arm.