Guidewire with varying properties

Patent metadata

Field	Value
Publication number	US-2016136396-A1
Application number	US-201615007013-A
Country	US
Kind code	A1
Filing date	Jan 26, 2016
Priority date	Sep 30, 2013
Publication date	May 19, 2016
Grant date	—

Abstract

A method of making a core metal element for a medical guidewire comprising 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. 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.

First claim

We claim:

1 . A method of making a core metal element for a medical guidewire 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;
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.

2 . The method of claim 1 , wherein swaging the wire over a second length includes swaging the wire over a second length that is between 20 mm and 16 mm, and swaging the wire over a third length includes swaging the wire over a third length that is between 14 mm and 10 mm.

3 . The method of claim 1 , wherein using a die set having a first diameter includes using a die set having a first diameter that is between 0.436 mm and 0.356 mm, and using a die set having a second diameter includes using a die set having a second diameter that is between 0.425 mm and 0.347 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 . The method of claim 1 , further including applying a reducing process to the wire, whereby the wire is reduced to having a constant diameter over the first length.

6 . The method of claim 5 , wherein applying a reducing process to the wire includes applying centerless grinding.

7 . The method of claim 1 , wherein swaging the wire over a second length includes swaging the wire over a second length that is less than the first length.

8 . A method of making a core metal element for a medical guidewire 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.

9 . The method of claim 8 , wherein swaging the wire over a second length includes swaging the wire over a second length that is between 8 mm and 4 mm, and swaging the wire over a third length includes swaging the wire over a third length that is between 8 mm and 4 mm.

10 . The method of claim 8 , wherein using a die set having a first diameter includes using a die set having a first diameter that is between 0.414 mm and 0.338 mm, and using a die set having a second diameter includes using a die set having a second diameter that is between 0.425 mm and 0.347 mm.

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

12 . The method of claim 8 , 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.

13 . The method of claim 8 , further including applying a reducing process to the wire, whereby the wire is reduced to having a constant diameter over the first length.

14 . The method of claim 13 , wherein applying a reducing process to the wire includes applying centerless grinding.

15 . A method of making a core metal element for a medical guidewire 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 certain diameter; and swaging the wire over a third length that eludes the distal end by using the die set, the third length being less than the second length.

16 . The method of claim 15 , wherein swaging the wire over a second length includes swaging the wire over a second length that is between 20 mm and 16 mm, and swaging the wire over a third length includes swaging the wire over a third length that is between 14 mm and 10 mm.

17 . The method of claim 15 , wherein using a die set having a certain diameter includes using a die set having a certain diameter that is between 0.414 mm and 0.338 mm.

18 . The method of claim 15 , further including swaging the wire over a fourth length of the wire that includes the distal end by using the die set, the fourth length being less than the third length.

19 . The method of claim 15 , further including applying a reducing process to the wire, whereby the wire is reduced to having a constant diameter over the first length.

20 . The method of claim 19 , wherein applying a reducing process to the wire includes applying centerless grinding.

21 . The method of claim 15 , wherein swaging the wire over a second length includes swaging the wire over a second length that is less than the first length.

22 . A method of making a core metal element for a medical guidewire 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 proximal point and a first distal point, by using a die set having a certain diameter and feeding the wire through the die set at a first feed rate; and
swaging the wire over a third length between a second proximal point and a second distal point by using the die set and feeding the wire through the die set at a second feed rate, the second feed rate being faster than the first feed rate, further including selecting the second distal point to coincide with the first proximal point;
and further including selecting the first distal point to coincide with the distal end of the wire.

23 . The method of claim 22 , wherein swaging the wire over a second length includes swaging the wire over a second length that is between 8 mm and 4 mm, and swaging the wire over a third length includes swaging the wire over a third length that is between 8 mm and 4 mm.

24 . The method of claim 22 , wherein using a die set having a certain diameter includes using a die set having a certain diameter that is between 0.414 mm and 0.338 mm.

25 . The method of claim 22 , wherein feeding the wire through the die set at a first feed rate includes feeding the wire through the die set at a firs

Assignees

• Abbott Cardiovascular Systems

Inventors

• Chludzinski Matthew James
• Simpson John Arthur

Classifications

• B21J7/145

  the hammers being driven by a rotating annular driving member · CPC title

• B21C1/00

  Manufacture of metal sheets, wire, rods, tubes or like semi-manufactured products by drawing · CPC title

• A61M2025/09133

  having specific material compositions or coatings; Materials with specific mechanical behaviours, e.g. stiffness, strength to transmit torque · CPC title

• A61M2025/09108

  Methods for making a guide wire · CPC title

• A61M25/09 Primary

  Guide wires · CPC title