Catheter with helical drive shaft and methods of manufacture

• US 9,770,259 B2
• Filed: 03/10/2015
• Issued: 09/26/2017
• Est. Priority Date: 09/01/2011
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Zeroni, Jenny, Sills, Cory David, Schuman, Victoria, Knutson, Marc D., Ladd, Bryan Matthew, Fruland, Benjamin Robert, Schneider, Lucas, Rice, Alexander J.
• Primary Examiner(s): Musser, Barbara J
• Application Number:
  US14/642,811
• Publication Number:
  US 20150238223A1
• Time in Patent Office: 931 Days
• Field of Search: None
• CPC Class Codes: A61B 17/320758 with a rotating cutting instrument, e.g. motor driven A61B17/320725, A61B17/32075 and A61B17/320783 take precedence; for removing intra-ocular material A61F9/00763; endoscopic rotatable cutting instruments A61B17/32002
• CPC Class Codes: A61B 17/320783 through side-hole, e.g. sliding or rotating cutter inside catheter
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: B29C 53/14 Twisting for textile fibres D01H
• CPC Class Codes: B29C 65/18 using heated tools
• CPC Class Codes: B29C 66/532 Joining single elements to the wall of tubular articles, hollow articles or bars
• CPC Class Codes: B29K 2077/00 Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2705/00 Use of metals, their alloys or their compounds, for preformed parts, e.g. for inserts
• CPC Class Codes: B29L 2031/7542 Catheters
• CPC Class Codes: Y10T 156/1043 Subsequent to assembly

Abstract

Drive shafts having helical blades and methods of making are disclosed. In one method a helical auger blade is formed by twisting or sculpting a heated polymer tube which has been placed over a cylindrical drive shaft. In another method a drive shaft is placed within a helical winding and heat is applied to melt polymer which has been coated over one or both of the drive shaft and helical winding.

Claims

1. A method of making a helical drive shaft having a helical auger blade with a desired pitch, depth, width and outer diameter comprising:

coating a cylindrical drive shaft with a polymer;

after said coating a cylindrical drive shaft with a polymer, placing the cylindrical drive shaft within a helical winding; and

after the drive shaft is placed within the helical winding, applying heat at a temperature sufficient to melt the polymer coating and join the helical winding to the drive shaft, the helical coil forming an auger blade having the desired pitch, depth, width and outer diameter.

2. The method of claim 1 wherein the helical winding comprises a metal wire made of copper, stainless steel, NiTi, a cobalt alloy, or other metal alloy having a rectangular cross-section with desired dimensions.

3. The method of claim 1 wherein the polymer comprises a thermoplastic polymer having a low glass transition temperature.

4. The method of claim 3 wherein the thermoplastic polymer is nylon.

5. The method of claim 1 wherein the polymer coating has a thickness in the range of 0.0005″

to 0.005″

.

6. The method of claim 1 wherein heat is applied at a temperature in the range of 100°

C. to 300°

C.

7. The method of claim 1 wherein the drive shaft comprises wire wound in alternating right and left hand layers.

8. The method of claim 1, further comprising forming a meniscus of the polymer on the helical winding during said applying heat.

9. The method of claim 8, further comprising cooling the polymer after said applying heat, wherein during cooling the meniscus hardens and mechanically anchors to the helical winding.

10. The method of claim 9, further comprising spot welding the helical winding to the cylindrical drive shaft at a plurality of locations.

11. A method of making a helical drive shaft having a helical auger blade with a desired pitch, depth, width and outer diameter comprising:

coating a helical winding with a polymer;

after said coating a helical winding with a polymer, placing a cylindrical drive shaft within the helical winding; and

after the drive shaft is placed within the helical winding, applying heat at a temperature sufficient to melt the polymer coating and join the helical winding to the drive shaft, the helical coil forming an auger blade having the desired pitch, depth, width and outer diameter.

12. The method of claim 11 wherein the helical winding comprises a metal wire made of copper, stainless steel, NiTi, a cobalt alloy, or other metal alloy having a rectangular cross-section with desired dimensions.

13. The method of claim 11 wherein the polymer comprises a thermoplastic polymer having a low glass transition temperature.

14. The method of claim 13 wherein the thermoplastic polymer is nylon.

15. The method of claim 11 wherein the polymer coating has a thickness in the range of 0.0005″

to 0.005″

.

16. The method of claim 11 wherein heat is applied at a temperature in the range of 100°

C. to 300°

C.

17. The method of claim 11 wherein the drive shaft comprises wire wound in alternating right and left hand layers.

18. The method of claim 11, further comprising forming a meniscus of the polymer on the helical winding during said applying heat.

19. The method of claim 18, further comprising cooling the polymer after said applying heat, wherein during cooling the meniscus hardens and mechanically anchors to the helical winding.

20. The method of claim 19, further comprising spot welding the helical winding to the cylindrical drive shaft at a plurality of locations.