Coaxial coil lock

Patent metadata

Field	Value
Publication number	US-9713479-B2
Application number	US-201615049367-A
Country	US
Kind code	B2
Filing date	Feb 22, 2016
Priority date	Jul 20, 2011
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A surgical instrument includes a housing and an elongated shaft extending distally therefrom. The elongated shaft includes a proximal portion, a distal portion and a flexible portion supported therebetween. The flexible portion permits pivotal movement of the distal portion of the elongated shaft and an end effector supported thereon. A locking mechanism is operatively associated with the flexible portion of the elongated shaft to selectively impede pivotal motion of the distal portion. The locking mechanism includes a locking coil disposed about an axis defined by the flexible portion of the elongated shaft. A distal end of the locking coil is coupled to the distal portion of the elongated shaft, and a proximal end of the locking coil is rotatable about the longitudinal axis to laterally approximate the locking coil to flexible portion, and thus frictionally engage the flexible portion of the elongated shaft to selectively impede articulating motion thereof.

First claim

What is claimed is:

1. A surgical instrument, comprising:
a housing;
an elongated shaft extending distally from the housing and defining a longitudinal axis, the elongated shaft including a distal portion supporting an end effector;
a flexible portion configured to support the distal portion of the elongated shaft such that bending of the flexible portion induces pivotal movement of the distal portion of the elongated shaft with respect to the longitudinal axis, the flexible portion including a central lumen defined therein; and
a locking mechanism configured to selectively impede pivotal motion of the distal portion of the elongated shaft, the locking mechanism including a first locking coil disposed about the central lumen of the flexible portion, the first locking coil including:
a distal end coupled to the flexible portion; and
a proximal end rotatable about the longitudinal axis in a first direction to laterally approximate the first locking coil relative to the central lumen of the flexible portion and rotatable in a second opposite direction to laterally separate the first locking coil from the central lumen of the flexible portion.

2. The surgical instrument according to claim 1 , wherein the flexible portion includes a support coil having gaps defined between individual windings of the support coil to facilitate bending of the support coil relative to the longitudinal axis.

3. The surgical instrument according to claim 2 , wherein the first locking coil is disposed about an inner surface of the support coil such that rotation of the proximal end of the first locking coil in the first direction increases an outer diameter of the first locking coil such that the first locking coil frictionally engages the inner surface of the support coil.

4. The surgical instrument according to claim 2 , wherein the locking mechanism further includes a second locking coil having:
a distal end coupled to the support coil; and
a proximal end rotatable about the longitudinal axis in a first direction to laterally approximate the second locking coil relative to the support coil and rotatable in a second opposite direction to laterally separate the second locking coil from the support coil.

5. The surgical instrument according to claim 4 , wherein the first and second locking coils are helically wound in a complementary direction with respect to a wound direction of the support coil.

6. The surgical instrument according to claim 4 , wherein the second locking coil is constructed of a generally flat band of a pliable material.

7. The surgical instrument according to claim 6 , wherein the generally flat band of the pliable material includes an adjustable width arranged to substantially cover the gaps defined in the support coil either in a straight configuration or an articulated configuration.

8. The surgical instrument according to claim 4 , wherein the second locking coil is coiled around the support coil such that the support coil is slidably disposed within the second locking coil and rotation of the proximal end of the second locking coil in the first direction decreases an inner diameter of the second locking coil such that the second locking coil frictionally engages the support coil.

9. The surgical instrument according to claim 4 , wherein the support coil includes a first helical groove defined on an inner surface of the support coil and a second helical groove defined on an outer surface of the support coil, wherein the first helical groove is configured to receive the first locking coil and the second helical groove is configured to receive the second locking coil.

10. The surgical instrument according to claim 1 , wherein the first locking coil is constructed from a round cross-section wire.

11. The surgical instrument according to claim 1 , further comprising at least one articulation cable extending at least partially through the elongated shaft having a distal end operatively coupled to the distal portion of the elongated shaft and a proximal end operatively coupled to an actuator such that manipulation of the actuator induces pivotal motion of the distal portion of the elongated shaft with respect to the longitudinal axis.

12. The surgical instrument according to claim 1 , wherein the end effector includes a pair of jaw members supported by the distal portion of the elongated shaft, wherein at least one of the jaw members is selectively movable between an open position substantially spaced from the other of the pair of jaw members and a closed position wherein the pair of jaw members are closer together.

13. An articulating surgical instrument, comprising:
a housing;
an elongated shaft extending distally from the housing defining a longitudinal axis and including a flexible portion having a support coil wound in a first direction; and
a locking coil extending along the support coil of the flexible portion such that the locking coil is wound about the support coil in a second direction, opposite the first direction of the support coil, the locking coil selectively transitionable to vary a frictional resistance between the locking coil and the support coil of the flexible portion.

14. The surgical instrument according to claim 13 , wherein the locking coil includes a distal end restrained from rotational motion and a proximal end rotatable about the longitudinal axis to selectively vary the rigidity of the flexible portion of the elongated shaft.

15. The surgical instrument according to claim 13 , further including a tensile member extending longitudinally through the elongated shaft, the tensile member selectively movable to articulate the flexible portion of the elongated shaft.

16. The surgical instrument according to claim 15 , wherein the tensile member includes at least one articulation cable selectively movable in opposite longitudinal directions to articulate the flexible portion of the elongated shaft.

17. The surgical instrument according to claim 16 , wherein the support coil of the flexible portion includes a cylindrical extrusion constructed of a flexible material, and wherein the at least one articulation cable is disposed within the cylindrical extrusion of the support coil of the flexible portion.

18. The surgical instrument according to claim 13 , wherein a proximal end of the support coil includes a flat mating surface configured to couple to a proximal portion of the elongated shaft and a distal end of the support coil includes a flat mating surface configured to couple to a distal portion of the elongated shaft.

19. The surgical instrument according to claim 18 , wherein the proximal end and the distal end of the support coil each include a reduced diameter relative to a longitudinally central portion of the flexible portion.

20. The surgical instrument according to claim 13 , further including an end effector having a pair of jaw members supported by a distal portion of the elongated shaft, wherein at least one of the jaw members is selectively movable between an open position substantially spaced from the other of the pair of jaw members and a closed position wherein the pair of jaw members are closer together.

21. The surgical instrument according to claim 20 , wherein at least one of the jaw members is adapted to couple to a source of electrosurgical energy.

Assignees

• Covidien Lp

Inventors

• Mueller Peter M

Classifications

• A61B2017/2905

  flexible · CPC title

• A61B2017/00309

  Cut-outs or slits · CPC title

• A61B17/2833 Primary

  Locking means · CPC title

• A61B2017/2927

  the angular position of the head being adjustable with respect to the shaft · CPC title

• A61B17/29 Primary

  Forceps for use in minimally invasive surgery · CPC title