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EP-4072434-B1 - INSTRUMENT SHAFTS WITH RELIEF FEATURES

EP4072434B1EP 4072434 B1EP4072434 B1EP 4072434B1EP-4072434-B1

Inventors

  • COOPER, THOMAS G.
  • HEYE, Isabelle Tonnesen
  • BROWN, Thomas Welch

Dates

Publication Date
20260513
Application Date
20201211

Claims (15)

  1. An instrument (104, 106, 1104), comprising: a tubular shaft (105, 107,1105); an end effector (226) coupled to a distal end portion of the tubular shaft (105, 107,1105); and a relief pattern extending circumferentially along a wall of the shaft (105, 107,1105) and along at least a portion of a length of the shaft (105, 107,1105), the relief pattern defining complementary interlocking engagement features on opposing sides of the relief pattern, each of the complementary interlocking engagement features comprising a base portion (540) having a first width, a neck portion (542) having a second width, and a head portion (544) having a third width; wherein the complementary interlocking engagement features each comprise first angled surfaces extending between the base portion (540) and the neck portion (542) and second angled surfaces extending between the neck portion (542) and the head portion (544), the first angled surfaces and the second angled surfaces oriented in first and second respective planes at a non-orthogonal angle to a longitudinal axis of the shaft, and the non-orthogonal angles of the first and second planes differing from each other, the complementary interlocking engagement features move relative to one another in response to bending of the shaft (105, 107,1105), and the complementary interlocking engagement features engage one another on one or both of tension and compression sides of the shaft (105, 107,1105) on a condition that the shaft (105, 107,1105) is bent to an angle within a predetermined range of bend angles.
  2. The instrument of claim 1, wherein the relief pattern extends generally in a helical pattern around a circumference of the shaft (105, 107,1105) along at least a portion of the shaft (105, 107,1105).
  3. The instrument of claim 1, wherein the relief pattern comprises a plurality of relief patterns spaced along a length of the shaft (105, 107,1105).
  4. The instrument of claim 1, wherein the relief pattern comprises a gap (546) between the complementary interlocking engagement features on the condition the shaft (105, 107,1105) is in a straight configuration.
  5. The instrument of claim 4, wherein a width of the gap (546) varies along the relief pattern.
  6. The instrument of any one of claims 1-5, wherein the second width is less than the first width and the third width.
  7. The instrument of claim 6, wherein each first angled surface tapers between the base portion (540) and the neck portion (542).
  8. The instrument of claim 7, wherein each second angled surface flares outwardly between the neck portion (542) and the head portion (544).
  9. The instrument of any one of claims 1-5, wherein, on the condition that the shaft (105, 107,1105) is bent to an angle within the predetermined range of bend angles, one or more of the head portions on a first of the opposing sides of the relief pattern engages with one or more base portions on a second of the opposing sides of the relief pattern.
  10. The instrument of claim 9, wherein engagement of the head portions precludes relative rotation between complementary interlocking engagement features on opposite sides of the relief pattern.
  11. The instrument of any one of claims 1-6, wherein: the relief pattern in the shaft (105, 107,1105) comprises a first relief pattern, and the shaft (105, 107,1105) comprises a second relief pattern spaced from the first relief pattern along a longitudinal axis of the shaft (105, 107,1105).
  12. The instrument of any one of claims 1-6, wherein the complementary interlocking engagement features engage one another on one or both of the tension and compression sides of the shaft (105, 107,1105) on the condition that the shaft (105, 107,1105) is bent to an angle of 20 degrees or less.
  13. The instrument of any one of claims 1-6, wherein the complementary interlocking engagement features engage one another on one or both of the tension and compression sides of the shaft (105, 107,1105) on the condition that the shaft (105, 107,1105) is bent to an angle of 10 degrees or less.
  14. The instrument of any one of claims 1-6, wherein the relief pattern comprises a helical pattern extending continuously around more than one circumference of the shaft (105, 107,1105).
  15. The instrument of claim 8, wherein the head portion of each complementary interlocking engagement feature comprises third angled surfaces tapered away from the second angled surfaces.

Description

TECHNICAL FIELD Aspects of the present disclosure relate to instrument shafts with relief features that increase flexibility of the shaft without increasing rotational backlash, and related systems and methods. INTRODUCTION Instruments, such as surgical or industrial instruments, can have a variety of configurations to perform various types of procedures. Some instrument systems are configured for minimally invasive surgery. In some such systems, each individual instrument includes an end effector at a distal end of a shaft for positioning at a site at which a procedure will take place. Such instruments may include transmission mechanisms positioned at a proximal end of the shaft and configured to mount the instrument to a manipulator system, such as a teleoperated (e.g., computer-controlled) manipulator system a manipulator system configured for manual operation. Transmission mechanisms of these tools can include numerous mechanical subsystems that receive mechanical inputs, e.g., from the manipulator system or manually via a user, and generate movement and actuation of the instrument, such as operation of the end effector, articulation of one or more joints of the shaft proximal of the end effector, shaft roll, and other operations or movements. Other instruments in medical, industrial, or other use applications can include shafts and associated components with similar construction and function. For various reasons, it may be desirable to provide shafts of such instruments with a degree of flexibility. For example, in a system with multiple instruments like those described above being configured to at a single location to carry out a procedure, the end effectors at the distal ends of the instrument shafts must be in parallel and in close proximity. Because of the potentially large number of mechanical components and subsystems contained in the associated transmission mechanisms at proximal ends of the shafts, the size of the transmission mechanisms constrains how closely together the proximal ends of the shafts can be positioned. Allowing the shaft some bending flexibility can enable the distal ends to be in close proximity while allowing sufficient clearance for the transmission mechanisms at the proximal end. In other applications and system architectures, a degree of flexibility may be desired for other reasons. But shafts made from flexible materials can behave in undesirable ways for certain applications, such as exhibiting higher axial compliance than desirable. There exists a need to provide an instrument shaft that exhibits a relatively high compliance in bending while also exhibiting relatively high axial and rotational stiffness. US 2017/071688 A1 relates to a device sized and shaped for insertion into a body comprising: at least one mechanical limb comprising: a support segment; a first flexible section extending from the support segment and terminating in a coupling section; and a second flexible section extending from the coupling section and terminating in a tool or a connector for a tool; wherein a long axis of one or more of the flexible sections is bendable in a single bending plane; wherein a long axis length of the first flexible section is at least double a maximum extent of the first flexible section perpendicular to a flexible section long axis; wherein a long axis length of the second flexible section is at least double a maximum extent of the second flexible section perpendicular to a flexible section long axis. US 2014/001231 A1 relates to surgical end effectors and fastener cartridges having firing lockout arrangements for preventing or limit a firing stroke when a cartridge has not been operably installed in the end effector or a spent cartridge has not been replaced. US 2012/143175 A1 relates to a Surgical instrument having proximal and distal end sections and a central section extending therebetween. A hollow outer shaft extends from the proximal to the distal end section. A drive element is rotatably mounted in the outer shaft and a tool is coupled to the drive element at the distal end section. The drive element comprises a flexible section arranged between the proximal and distal end sections which consists of a plurality of ring segments each of which has a first and a second end region. The first end region comprises projections which protrude in the axial direction and the second end region comprises recesses for accommodating the projections. The ring segments intermesh in an articulated manner by means of the projections and recesses. The outer shaft comprises an articulation Zone which connects the distal end section and the central section together in an articulated manner. US 2019/365202 A1 relates to a patient-side support system includes a base, a platform movably coupled to the base, manipulator assemblies coupled to the platform, instruments, each of the instruments being coupled to a different one of the manipulator assemblies, each of the instruments including