Endoscopic Working Channel and Method of Making Same

• US 20100256445A1
• Filed: 06/18/2010
• Published: 10/07/2010
• Est. Priority Date: 12/07/2006
• Status: Abandoned Application

• Current Assignee: International Polymer Engineering, Inc.
• Original Assignee: International Polymer Engineering, Inc.
• Inventors: Fitzpatrick, Craig
• Application Number:
  US12/819,075
• Publication Number:
  US 20100256445A1
• Time in Patent Office: Days
• US Class Current: 600/101
• CPC Class Codes: A61B 1/00071 Insertion part of the endoscope body A61B1/0055 takes precedence
• CPC Class Codes: A61B 1/00075 with externally roughened shaft
• CPC Class Codes: A61B 1/0011 Manufacturing of endoscope parts
• CPC Class Codes: A61B 1/012 characterised by internal passages or accessories therefor
• CPC Class Codes: A61L 29/041 obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C08L 27/18 Homopolymers or copolymers or tetrafluoroethene

Abstract

A working channel for an endoscope or similar device having concentric porous and nonporous polymer tubes that are adhered or bonded together. A support wire may be wrapped around a nonporous inner tube and provides increased flexibility and resistance to compression and kinking. A porous outer tube fits over the support wire and inner tube and bonds to the inner tube, encapsulating the support wire. The outer tube may have a smooth or corrugated exterior, depending on the intended use of the working channel. Methods for manufacturing the working channel are also disclosed.

Claims

1. A working channel comprising:

a. a nonporous inner tube having a discrete length; and

b. a porous outer tube having substantially the same length as the inner tube, the outer tube being fit over the inner tube and bonded to the inner tube.

2. The working channel of claim 1 wherein the outer tube is made of expanded polytetrafluoroethylene.

3. The working channel of claim 2 wherein the outer tube has a substantially smooth external surface.

4. The working channel of claim 3 wherein the substantially smooth external surface of the outer tube is formed by winding a compression wrap around the outer tube before the outer tube is bonded to the inner tube, the compression wrap being wound so that there is substantially no space between adjacent turns of the compression wrap.

5. The working channel of claim 3 wherein the smooth external surface of the outer tube is formed by feeding the inner tube and outer tube through a compression die.

6. The working channel of claim 2 wherein the outer tube has a corrugated external surface.

7. The working channel of claim 6 wherein the corrugated external surface of the outer tube is formed by winding a compression wrap around the outer tube before the outer tube is bonded to the inner tube, the compression wrap being wound so that there is space between adjacent turns of the compression wrap.

8. The working channel of claim 1 further comprising a support wire wound helically around the inner tube, the outer tube being fit over both the support wire and the inner tube and bonded to the inner tube between adjacent turns of the support wire.

9. The working channel of claim 8 wherein the outer tube has a substantially smooth external surface.

10. The working channel of claim 9 wherein the substantially smooth external surface of the outer tube is formed by winding a compression wrap around the outer tube before the outer tube is bonded to the inner tube, the compression wrap being wound so that there is no space between adjacent turns of the compression wrap.

11. A method of making a working channel, the method comprising:

a. fitting a porous outer tube over a nonporous inner tube, the outer tube and inner tube having substantially the same length; and

b. bonding the outer tube to the inner tube.

12. The method of claim 11 wherein bonding the outer tube to the inner tube comprises feeding the inner tube and outer tube through a compression die.

13. The method of claim 12 wherein the compression die applies sufficient pressure to bond the outer tube to the inner tube.

14. The method of claim 12 wherein bonding the outer tube to the inner tube further comprises heating the outer tube and inner tube until the outer tube heat bonds to the inner tube.

15. The method of claim 12 wherein the compression die makes the external surface of the outer tube substantially smooth.

16. The method of claim 11 wherein bonding the outer tube to the inner tube comprises:

a. winding a compression wrap onto the external surface of the outer tube;

b. heating the outer tube and inner tube until the outer tube heat bonds to the inner tube;

c. allowing the outer tube and inner tube to cool; and

d. removing the compression wrap.

17. The method of claim 16 wherein the compression wrap is wound leaving no space between adjacent turns of the compression wrap, so that the external surface of the outer tube is substantially smooth after bonding.

18. The method of claim 16 wherein the compression wrap is wound leaving space between adjacent turns of the compression wrap, so that the external surface of the outer tube is corrugated after bonding.

19. The method of claim 11 further comprising loading the inner tube onto a mandrel prior to fitting the outer tube over the inner tube, the mandrel being slightly longer than the inner tube.

20. The method of claim 19 wherein bonding the outer tube to the inner tube comprises:

a. winding a compression wrap onto the external surface of the outer tube;

b. heating the outer tube and inner tube until the outer tube heat bonds to the inner tube;

c. allowing the outer tube and inner tube to cool; and

d. removing the compression wrap.

21. The method of claim 20 wherein the compression wrap is wound leaving no space between adjacent turns of the compression wrap, so that the external surface of the outer tube is substantially smooth after bonding.

22. The method of claim 20 wherein the compression wrap is wound leaving space between adjacent turns of the compression wrap, so that the external surface of the outer tube is corrugated after bonding.

23. The method of claim 19 further comprising winding a support wire around the inner tube before fitting the outer tube over the inner tube.

24. The method of claim 23 wherein bonding the outer tube to the inner tube comprises:

a. winding a compression wrap onto the external surface of the outer tube so that the compression wrap is positioned laterally between adjacent turns of the support wire;

b. heating the outer tube and inner tube until the outer tube heat bonds to the inner tube;

c. allowing the outer tube and inner tube to cool; and

d. removing the compression wrap.

25. The method of claim 24 wherein the compression wrap is wound leaving no space between adjacent turns of the compression wrap, so that the external surface of the outer tube is substantially smooth after bonding.