Wrist assembly for articulating laparoscopic surgical instruments

Patent metadata

Field	Value
Publication number	US-9717517-B2
Application number	US-201514937126-A
Country	US
Kind code	B2
Filing date	Nov 10, 2015
Priority date	Apr 9, 2012
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

An articulating laparoscopic instrument including a handle, an outer shaft, an end effector, and a wrist assembly. The wrist assembly connects the end effector to the shaft and includes torque and articulation mechanisms. The torque mechanism includes a plurality of links disposed over the rod and connected with one another in a pivotable yet rotationally locked fashion. The articulation mechanism includes a plurality of articulation member disposed over the rod to collectively define a deflection section. The links freely rotate relative to the articulation members, with the rod and links collectively bending in response to a change in shape of the deflection section.

First claim

We claim:

1. An articulating surgical instrument comprising:
an end effector attached to a distal end of a wrist assembly, where the wrist assembly includes:
a torque mechanism including a plurality of links disposed between the shaft end and the end effector, where the links are constructed and operate to transfer a rotational force from a proximal-most link to the end effector, and
an articulation mechanism including a plurality of articulation members that collectively define a deflection section, where the articulation mechanism is configured and operates to spatially articulate the end effector along a single plane relative to a proximal-most articulation member;

where the wrist assembly is configured such that the links spatially articulate with articulation of the deflection section relative to a common longitudinal axis of the wrist assembly, and the links rotate independently of articulation of the articulation members;
where each of the articulating members defines a central bore, a first side channel and a second side channels opposite the first side channel relative to the central bore, the articulation mechanism further including a first cable segment threaded through the first side channel of each of the articulation members; and a second cable segment threaded through the second side channel of each of the articulation members;
where the articulation mechanism is configured such that increased tension in the first cable segment causes the deflection section to deflect in a direction of the first cable segment;
where the wrist assembly is configured to provide:
a usage mode in which the cable segments are tensioned sufficiently such that adjacent articulation members physically contact each other and adjacent links physically contact each other, wherein each of the links is associated with a corresponding one of the articulation members; and
a cleaning mode in which sufficient slack in the cable segments provides that adjacent links are longitudinally spaced but not disassembled from one another and that adjacent articulation members are longitudinally spaced but not disassembled from one another, where the spacing is sufficient to permit direct cleaning.

2. The surgical instrument of claim 1 , configured such that, in the usage mode, a first link is forced to laterally translate by lateral translation of a first articulation member during operation of the articulation mechanism that causes the deflection section to articulate, and further wherein the first link rotates relative to the first articulation member during an operation of the torque mechanism that causes the end effector to rotate.

3. The surgical instrument of claim 2 , where, in the usage mode, at least a portion of the first link is moveably disposed within the first articulation member.

4. The surgical instrument of claim 3 , wherein the torque mechanism further includes a torque shaft connected to the proximal-most link.

5. The surgical instrument of claim 1 , wherein the wrist assembly further includes:
an end effector operation mechanism including a flexible rod extending through the torque shaft and coupled to the end effector.

6. The surgical instrument of claim 5 , wherein the links and the articulation members are disposed over the flexible rod.

7. The surgical instrument of claim 6 , wherein the flexible rod is slidably disposed within the torque shaft.

8. The surgical instrument of claim 5 , wherein the end effector includes a first body moveably associated with a second body and further wherein the end effector operation mechanism is configured such that longitudinal movement of the flexible rod relative to the end effector causes the first body to move relative to the second body.

9. The surgical instrument of claim 1 , wherein each of the links defines a male end portion opposite a female end portion, and further wherein when adjacent links are physically connected in direct contact with one another, the male end portion of a first link is received within the female end of an immediately adjacent second link at a link interface such that the first link can laterally pivot relative the second link at the link interface so that a rotational force applied to the first link is transferred to the second link at the link interface.

10. The surgical instrument of claim 9 , wherein the male end portion includes a polygonal ball head, and the female end portion forms a polygonal socket head configured to selectively receive the ball head.

11. The surgical instrument of claim 10 , wherein each link defines a longitudinal axis, and further wherein the polygonal ball head has a polygonal shaped cross-section in a plane perpendicular to the longitudinal axis.

12. The surgical instrument of claim 10 , wherein a cross-section of the ball head in a plane passing through the longitudinal axis has curved lateral edges.

13. The surgical instrument of claim 12 , wherein the socket head defines a receptacle having the polygonal shape such that when the male end portion of the first link is received within the female end portion of the second link, rotation of the of the first link is directly transferred to the second link via a locked interface between the polygonal shapes, and the first link can pivot relative to the second link via the curved lateral edges sliding relative to the receptacle.

14. The surgical instrument of claim 9 , wherein the torque mechanism further includes a connector fixed to and extending proximally from the end effector, the connector forming one of the male end portion and the female end portion.

15. The surgical instrument of claim 1 , wherein each of the plurality of links is discrete from a remainder of the plurality of links.

16. The surgical instrument of claim 1 , wherein the cable segments are comprised by a single cable.

17. The surgical instrument of claim 1 , wherein the wrist assembly is configured such that, during operation of the articulation mechanism to change a shape of the deflection section, the deflection section applies a force on to the plurality of links so that the plurality of links collectively assume a shape of the deflection section.

18. The surgical instrument of claim 17 , wherein the wrist assembly further includes:
an end effector operation mechanism including a flexible rod extending through the torque shaft and coupled to the end effector such that longitudinal movement of the rod relative to the end effector causes a first end effector body to move relative to a second end effector body;
being configured such that, during operation of the articulation mechanism to change a shape of the deflection section, a portion of the flexible rod surrounded by the deflection section assumes a shape of the deflection section.

19. The surgical instrument of claim 1 , further comprising actuators carried by a handle, each actuator being configured to facilitate user-controlled operation of each corresponding mechanism.

20. The surgical instrument of claim 1 , wherein the links are configured such that upon transitioning from the cleaning mode to the usage mode in response to increased tension of the cable segments, adjacent links self-align and engage in physical contact with one another.

Assignees

• Carefusion 2200 Inc

Inventors

• Stroup David Karl
• Deptala Arthur

Classifications

• A61B2017/2929

  with a head rotatable about the longitudinal axis of the shaft · CPC title

• A61B2017/2908

  Multiple segments connected by articulations · CPC title

• A61B2017/2905

  flexible · CPC title

• A61B2017/2903

  transferring rotary motion · CPC title

• A61B2017/00323

  Cables or rods · CPC title