Endoscope shaft with superelastic alloy spiral frame and braid

• US 6,485,411 B1
• Filed: 04/12/2000
• Issued: 11/26/2002
• Est. Priority Date: 04/12/2000
• Status: Expired due to Term

• Current Assignee: Gyrus ACMI, Inc. (Olympus Corporation)
• Original Assignee: Circon Corp. (Olympus Corporation)
• Inventors: Konstorum, Gregory S., Grabover, Edward A.
• Primary Examiner(s): MULCAHY, JOHN M
• Application Number:
  US09/547,686
• Time in Patent Office: 958 Days
• Field of Search: 600/139-143, 604/95.01, 604/95.04, 604/95.05, 604/264, 604/523, 604/524, 604/525, 604/526, 604/527, 604/530, 604/531
• US Class Current: 600/139
• CPC Class Codes: A61B 1/00078 with stiffening means
• CPC Class Codes: A61B 1/0055 Constructional details of insertion parts, e.g. vertebral elements
• CPC Class Codes: A61B 1/0058 using shape-memory elements

Abstract

An endoscope having a control section and a shaft extending from the control section. The shaft comprises an outer cover; a tubular braid member located, at least partially, inside the outer cover; and a support frame located, at least partially, inside the tubular braid member. The support frame comprises a shape memory member which is spiral shaped. The shape memory member is comprised of a superelastic shape memory alloy. A first length of the support frame comprises the shape memory member having a first width and/or thickness a second length of the tubular shape comprises the shape memory member having a different second width and/or thickness such that the support frame has different respective stiffnesses along the first and second lengths.

Claims

1. An endoscope having a control section and a shaft extending from the control section, the shaft comprising:

an outer cover;

a tubular braid member located, at least partially, inside the outer cover; and

a support frame located, at least partially, inside the tubular braid member, the support frame comprising a shape memory member which is spiral shaped, wherein the shape memory member is comprised of a superelastic shape memory alloy, and wherein a first length of the support frame comprises the shape memory member having a first width and a second length of the support frame comprises the shape memory member having a different second width such that the support frame has different respective stiffnesses along the first and second lengths.

2. An endoscope as in claim 1 wherein the shape memory member comprises a cross-sectionally flat shape.

3. An endoscope as in claim 1 wherein a third length of the support frame comprises the shape memory member having a third width which is different than the first and second widths.

4. An endoscope as in claim 1 wherein a spiral gap spacing is provided between adjacent spiral sections of the shape memory member.

5. An endoscope as in claim 4 wherein the spiral gap spacing is substantially uniform along both the first and second lengths.

6. An endoscope as in claim 4 wherein the shape member comprises a tube member with the spiral gap spacing being laser cut or electrical discharge machined into the tube member.

7. An endoscope as in claim 1 wherein the shape memory member comprises a strip which is formed into the spiral shape and heat treated to shape memory memorize the spiral shape.

8. An endoscope as in claim 1 wherein the tubular braid member comprises interwoven thread members comprised of superelastic shape memory alloy.

9. An endoscope as in claim 1 wherein the shape memory member comprises at least two sections having.

10. An endoscope as in claim 1 wherein the spiral shape of the support frame extends along a majority of the support frame.

11. An endoscope as in claim 1 wherein the support frame comprises the shape memory member as a first shape memory member and further comprises a second shape memory member comprised of superelastic shape memory alloy, the second shape memory member being attached to a front end of the first shape memory member, and wherein the second shape memory member comprises a tubular shape with slots in different directions into lateral sides of the second shape memory member, the tubular shape having a center aperture occupying a majority of a cross-sectional area of the tubular shape.

23. A method as in claim 1 wherein the step of providing comprises providing the member as a strip and the step of forming comprises wrapping the strip in the spiral shape with a form and heat treating the strip to shape memory memorize the spiral shape.

12. An endoscope having a control section and a shaft extending from the control section, the shaft comprising:

an outer cover;

a tubular braid member located, at least partially, inside the outer cover; and

a support frame located, at least partially, inside the tubular braid member, the support frame comprising a shape memory member which is spiral shaped, wherein the shape memory member is comprised of a superelastic shape memory alloy, and wherein a first length of the support frame comprises the shape memory member having a first width and a second length of the tubular shape comprises the shape memory member having a different second width such that the support frame has different respective stiffnesses along the first and second lengths, wherein the tubular braid member comprises interwoven thread members comprised of superelastic shape memory alloy, wherein the tubular braid member is heat treated at a first longitudinal length for the thread members to memorize their shapes while at the first longitudinal length and the tubular braid member is attached over the support frame as a second longer longitudinal length.

13. An endoscope having a control section and a shaft extending from the control section, the shaft comprising:

a front end member;

a rear end member;

a support frame connecting the front end member to the rear end member; and

a tubular braid member surrounding the support frame, the tubular braid member being comprised of interwoven thread members comprised of superelastic shape memory alloy, wherein the tubular braid member is heat treated to memorize home shapes of the thread members and the tubular braid member is then subsequently elongated and fixedly attached to the front and rear members with the thread members being elastically deformed towards a straightened shape.

14. An endoscope as in claim 13 wherein the thread members comprise flat wires having a general cross-sectionally flat shape.

15. An endoscope as in claim 13 wherein a wall thickness of the tubular braid member is about 2.2 times or less a wall thickness of the thread members.

16. An endoscope as in claim 13 wherein the memorized home shapes of the thread members comprise a wavy shape along their lengths, wherein recesses formed by waves of the wavy shape form thread receiving areas, and wherein a height of the thread receiving areas is about the same as a thickness of the thread members.

17. An endoscope as in claim 13 wherein the support frame comprises a spiral riember made of a super-elastic shape memory alloy.

18. An endoscope as in claim 17 wherein the spiral member comprises at least two section lengths with two respective different wall widths of the spiral member measured parallel to an axis of the spiral shape.

19. A method of manufacturing an endoscope shaft comprising steps of:

providing a member comprised of superelastic shape memory alloy;

forming the member into a support frame having a general spiral shape, wherein a first length of the support frame has spiral sections which each have a first width measured along an axis of the spiral shape and a second length of the member has spiral sections which each have a second different width measured along the axis of the spiral shape;

connecting the support frame to a front end member and a rear end member; and

connecting a tubular shaped braid member to the front and rear end members over the support frame.

20. A method as in claim 19 wherein the step of providing comprises providing the member as a solid tube and the step of forming comprises forming a spiral gap through the tube along the tube.

21. A method as in claim 20 wherein the spiral gap is formed by laser cutting through the tube.

22. A method as in claim 20 wherein the spiral gap is formed by electrical discharge machine cutting through the tube.

24. A method as in claim 19 further comprising reducing a wall thickness of the member along at least one section length of the support frame.

25. A method as in claim 19 wherein the step of forming forms the member in the spiral shape with a uniform gap spacing between adjacent ones of the spiral sections of the member.

26. A method as in claim 19 wherein the step of forming the member into the support frame comprises forming the general spiral shape along a majority of length of the support frame.

27. A method as in claim 19 further comprising connecting a second shape memory member to a front end of the general spiral shape between the general spiral shape and the front end member, the second shape memory member comprising a tubular shape with slots in different directions into lateral sides of the second shape memory member, the tubular shape having a center aperture occupying a majority of a cross-sectional area of the tubular shape.

30. An endoscope as in claim 20 wherein the shaft comprises an active deflection section operated by the control section and a passive deflection section, wherein the first frame member is located in the passive deflection section and the second frame member is located in the active deflection section.

31. An endoscope as in claim 30 wherein the second frame member comprises at least one tube of superelastic material with slots extending into at least one lateral side of the at least one tube.

28. A method of manufacturing a tubular braid member for use in an endoscope shaft comprising steps of:

weaving thread members into a general tubular woven shape, the thread members being comprised of super elastic shape memory alloy; and

heat treating the general tubular woven shape such that the thread members memorize a first wavy shape as home positions,

wherein a longitudinal length of the tubular woven shape, when the tubular woven shape is heat treated, is provided as less than an intended longitudinal length of the tubular braid member when assembled into the endoscope shaft such that the tubular woven shape must be longitudinally lengthened when assembled into the endoscope shaft with the thread members being elastically deformed from their shape memory memorized home positions towards a straightened position, and wherein internal forces from within the thread members allow the thread members to individually resist being deformed from their memorized home positions.

29. In an endoscope having a control section and a shaft connected to the control section, the improvement comprising:

the shaft including a support frame comprising a first bendable frame member having a general tubular shape connected with a second frame member having a general tubular shape, wherein the second frame member is connected to a front end of the first frame member, and wherein the first frame member is comprised of super elastic material, is spiraled to form its general tubular shape, and is located along a majority of the length of the shaft, and the shaft further comprises a tubular braid member located over the first and second frame members.

32. An. endoscope as in claim 29 wherein the first frame member is spiraled along a majority of the first frame member'"'"'s longitudinal length.