Guidewire with varying properties

• US 10,335,580 B2
• Filed: 01/26/2016
• Issued: 07/02/2019
• Est. Priority Date: 09/30/2013
• Status: Active Grant

• Current Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Abbott Cardiovascular Systems Incorporated (Abbott Laboratories Incorporated)
• Inventors: Chludzinski, Matthew James, Simpson, John Arthur
• Primary Examiner(s): Swiatocha, Gregory D
• Application Number:
  US15/007,013
• Publication Number:
  US 20160136396A1
• Time in Patent Office: 1,253 Days
• CPC Class Codes: A61M 2025/09108 Methods for making a guide wire
• CPC Class Codes: A61M 2025/09133 having specific material compositions or coatings; Materials with specific mechanical behaviours, e.g. stiffness, strength to transmit torque
• CPC Class Codes: A61M 2205/0216 Materials providing elastic properties, e.g. for facilitating deformation and avoid breaking
• CPC Class Codes: A61M 25/09 Guide wires
• CPC Class Codes: B21C 1/00 Manufacture of metal sheets, metal wire, metal rods, metal tubes by drawing
• CPC Class Codes: B21F 45/008 of medical instruments, e.g. stents, corneal rings medical science A61
• CPC Class Codes: B21J 7/145 the hammers being driven by a rotating annular driving member

Abstract

A method of making a core metal element for a medical guidewire including providing a wire of nickel titanium alloy having a length that includes a proximal portion having a first diameter and a distal portion having a second diameter. The method further includes applying cold work to the distal portion and not applying cold work to the proximal portion, thereby imparting to the distal portion a third diameter that is smaller than the second diameter; and then applying a reducing process to the wire whereby the proximal portion is reduced to have a fourth diameter that is less than the first diameter.

Claims

1. A method of making a medical guidewire core element comprising:

providing a wire of nickel titanium alloy with superelastic properties having a proximal end and a distal end, wherein a first length separates the proximal end from the distal end;

applying cold work to the wire through a rotary swaging machine in a sequence that comprises;

swaging the wire over a second length that includes the distal end by using a die set having a first diameter wherein the second length is less than the first length;

swaging the wire over a third length that includes the distal end by using a die set having a second diameter, the third length being less than the second length, and the second diameter being less than the first diameter; and

applying a reducing process to the wire, following swaging the wire over the second length and the third length, whereby the wire is reduced to have a constant diameter over the first length wherein the reducing process includes applying centerless grinding.

2. The method of claim 1, wherein wherein the second length is between 16 mm and 20 mm and the third length is between 10 mm and 14 mm.

3. The method of claim 1, wherein wherein the first diameter is between 0.356 mm and 0.436 mm and the second diameter is between 0.347 mm and 0.425 mm.

4. The method of claim 1, further including swaging the wire over a fourth length of the wire that includes the distal end by using a die set having a third diameter, wherein the fourth length is less than the third length and the third diameter is less than the second diameter.

5. A method of making a medical guidewire core element comprising:

providing a wire of nickel titanium alloy with superelastic properties having a proximal end and a distal end, wherein a first length separates the proximal end from the distal end;

applying cold work to the wire through a rotary swaging machine in a sequence that comprises;

swaging the wire over a second length between a first distal point and a first proximal point by using a die set having a first diameter;

swaging the wire over a third length between a second distal point and a second proximal point by using a die set having a second diameter, the second diameter being larger than the first diameter, further including selecting the second distal point to coincide with the first proximal point; and

applying a reducing process to the wire, following swaging the wire over the second length and the third length, whereby the wire is reduced to having a constant diameter over the first length wherein the reducing process includes applying centerless grinding.

6. The method of claim 5, wherein wherein the second length is between 4 mm and 8 mm and the third length is between 4 mm and 8 mm.

7. The method of claim 5, wherein the first diameter is between 0.338 mm and 0.414 mm and the second diameter is between 0.347 mm and 0.425 mm.

8. The method of claim 5, further including selecting the first distal point to coincide with the distal end.

9. The method of claim 5, further including swaging the wire over a fourth length of the wire between a third distal point and a third proximal point by using a die set having a third diameter, the third diameter being larger than the second diameter, and further including selecting the third distal point to coincide with the second proximal point.