Jaw force control for electrosurgical forceps

Patent metadata

Field	Value
Publication number	US-2017196620-A1
Application number	US-201614992075-A
Country	US
Kind code	A1
Filing date	Jan 11, 2016
Priority date	Jan 11, 2016
Publication date	Jul 13, 2017
Grant date	—

Abstract

A surgical instrument includes a first shaft, a second shaft, and a hinge. The first shaft includes a proximal handle and a distal jaw member. The second shaft includes a first segment that has a proximal handle and a second segment that has a distal jaw member. One of the first and second shafts is pivotal relative to the other to pivot the jaw members between an open configuration where the jaw members are spaced relative to one another and an activatable configuration where the jaw members are closer to one another and suitable for applying electrosurgical energy to tissue disposed therebetween. The hinge couples the first and second segments to one another. The first and second segments have a straight configuration where the first and second segments align with a longitudinal axis and a pivoted configuration where the second segment is disposed at an angle relative to the longitudinal axis.

First claim

What is claimed:

1 . A surgical instrument, comprising:
a first shaft having a proximal handle and a distal jaw member; a second shaft having a first segment and a second segment, the first segment including a proximal handle of the second shaft and the second segment including a distal jaw member of the second shaft, at least one of the first and second shafts pivotal relative to the other to pivot the jaw members between an open configuration wherein the jaw members are spaced relative to one another and an activatable configuration wherein the jaw members are closer to one another and suitable for applying electrosurgical energy to tissue disposed therebetween; and a hinge coupling the first segment of the second shaft to the second segment of the second shaft, the first and second segments having a straight configuration wherein the first and second segments align with a longitudinal axis defined through the second shaft and a pivoted configuration wherein the second segment is disposed at an angle relative to the longitudinal axis.

2 . The surgical instrument according to claim 1 , wherein the hinge biases the first and second segments towards the straight configuration.

3 . The surgical instrument according to claim 1 , wherein the first segment pivots relative to the second segment when a closure force of the jaw members exceeds a threshold closure force.

4 . The surgical instrument according to claim 3 , wherein the threshold closure force is equal to a predetermined closure force limit.

5 . The surgical instrument according to claim 3 , wherein the threshold closure force is less than a predetermined closure force limit.

6 . The surgical instrument according to claim 1 , wherein the hinge includes a fastener, wherein the first segment includes a distally extending first flange defining a first opening disposed over the fastener, and wherein the second segment includes a proximally extending second flange defining a second opening disposed over the fastener.

7 . The surgical instrument according to claim 6 , wherein the hinge includes a resilient member disposed about the fastener between the first and second flanges.

8 . The surgical instrument according to claim 7 , wherein the resilient member is a torsion spring.

9 . The surgical instrument according to claim 7 , wherein the resilient member has a constant spring rate.

10 . The surgical instrument according to claim 7 , wherein the resilient member has a progressive spring rate

11 . The surgical instrument according to claim 7 , wherein the first and second flanges each define a slot that receive a respective arm of the resilient member.

12 . The surgical instrument according to claim 7 , wherein the second flange defines a boss that extends towards the first flange, the boss defining a passage coaxial with the second opening and having a diameter larger than the second opening.

13 . The surgical instrument according to claim 12 , wherein a body of the resilient member is received within the passage of the boss.

14 . The surgical instrument according to claim 1 , wherein the first shaft includes a stop extending from an inner surface of the handle of the first shaft towards the handle of the second shaft, the stop configured to prevent the second shaft from pivoting beyond a closed configuration.

15 . The surgical instrument according to claim 14 , wherein the second shaft includes a lock extending from an inner surface of the handle of the second shaft towards the handle of the first shaft, and wherein the stop defines an opening, the lock including a detent configured to engage the opening to prevent the second shaft from pivoting towards the open configuration.

16 . A method of limiting closure force while grasping tissue with a surgical instrument, the method comprising:
positioning tissue between jaw members of the surgical instrument; moving handles of first and second shafts of the surgical instrument towards one another to pivot the jaw members towards a closed configuration to apply pressure to tissue disposed between the jaw members; and limiting the pressure to a predetermined pressure limit by allowing a first segment of the second shaft to pivot about a common hinge relative to a second segment of the second shaft if the closure pressure exceeds the predetermined pressure limit.

17 . The method according to claim 16 , further comprising delivering electrosurgical energy with the jaw members to the tissue between the jaw members when the first segment is pivoted relative to the second segment.

18 . The method according to claim 16 , further comprising abutting a stop of the first shaft with the handle of the second shaft.

19 . The method according to claim 16 , further comprising locking the handle of the second shaft to a stop of the first shaft by engaging an opening defined by the stop with a lock extending from the handle of the second shaft.

Assignees

• Covidien Lp

Inventors

• Jadhav Amarsinh D

Classifications

• A61B2090/035

  preventing further rotation · CPC title

• A61B2090/032

  pressure limiting, e.g. hydrostatic · CPC title

• A61B2018/0231

  Characteristics of handpieces or probes · CPC title

• A61B2018/0091

  Handpieces of the surgical instrument or device · CPC title

• A61B2018/00642

  with feedback, i.e. closed loop control · CPC title