Guidewire with stiffness blending connection
View Patent ↗Alternative designs and materials suitable for connecting different guidewire sections together. More particularly, connecting two portions of a guidewire having different material compositions with a connector having a third composition which is readily weldable to each of the dissimilar portions of the guidewire. A transition area may be designed to provide a region of desired flexibility characteristics.
1. A guidewire, comprising:
a proximal section having a distal portion, the proximal section comprising a first material, wherein the first material comprises stainless steel;
a distal section having a proximal portion, the distal section comprising a second material, wherein the second material comprises a nickel-titanium alloy; and
a connector disposed adjacent and welded to the distal portion of the proximal section and the proximal portion of the distal section, the connector comprising a third material different from the first material and the second material, the third material comprising nickel-chromium-molybdenum alloy, C276, or B2 alloy that is compatible for welding to both stainless steel and nickel-titanium alloy.
2. A guidewire as in claim 1 , wherein the proximal section has a first flexibility and the distal section has a second flexibility, and wherein the distal portion of the proximal section and the proximal portion of the distal section overlap to define a region that blends the first flexibility with the second flexibility.
3. A guidewire as in claim 1 , wherein the distal portion of the proximal section has a reduced size portion and the proximal portion of the distal section has a reduced size portion.
4. A guidewire as in claim 3 , wherein the reduced size portions have a taper.
5. A guidewire as in claim 3 , wherein the reduced size portions have an interlocking shape.
6. A guidewire as in claim 3 , wherein at least a portion of the connector is disposed between the reduced size distal portion of the proximal section and the reduced sized proximal portion of the distal section.
7. A guidewire as in claim 1 , wherein the third material comprises a nickel-chromium-iron alloy.
8. A guidewire as in claim 1 , wherein the connector comprises a tubular member disposed about the distal portion of the proximal section and the proximal portion of the distal section.
9. A guidewire as in claim 8 , wherein the tubular connector has an outside diameter that is the same as an outside diameter of the proximal section.
10. A guidewire as in claim 9 , wherein the tubular connector has an outside diameter that is the same as an outside diameter of the distal section.
11. A guidewire, comprising:
a proximal section having a distal portion, the proximal section comprising stainless steel;
a distal section having a proximal portion, the distal section comprising a nickel-titanium alloy; and
a connector disposed adjacent and welded to the distal portion of the proximal section and the proximal portion of the distal section, the connector comprising a nickel-chromium-molybdenum alloy.
12. A guidewire as in claim 11 , wherein the proximal section has a first flexibility transition region having a first flexibility and the distal section has a second flexibility transition region having a second flexibility, and wherein flexibility transition regions overlap to define a region that blends the first flexibility with the second flexibility.
13. A guidewire as in claim 12 , wherein at least a portion of the connector is disposed between the flexibility transition regions.
14. A guidewire as in claim 11 , wherein the connector comprises a nickel-chromium-molybdenum-iron alloy tube.
15. A guidewire, comprising:
a proximal section comprising stainless steel;
a distal section comprising nickel-titanium alloy; and
a connector comprising a nickel-chromium-molybdenum alloy which is welded to and connects the proximal and distal sections.