Joined metal tubing and method of manufacture
View Patent ↗A generally hollow article for use as or incorporation within a medical instrument navigable through body vessels of a human subject is provided. The article is defined by two metal pieces, such as nitinol and stainless steel, having different performance characteristics. At least a portion of the two pieces are arranged into an alternating pattern and joined together to define a joint or junction. The two pieces may each be provided as a tube having a spiral-cut section that is configured to be intermeshed with the spiral-cut section of the other metal. The article may also include a radiopaque material for improved placement within the body, which material may also be provided as a tube with a spiral-cut section to be intermeshed and joined with the first and second pieces.
1. A hollow tubular article for a medical device adapted to be received by a body vessel, comprising:
a first hollow tube piece substantially comprised of a first metal, said first hollow tube piece is a first tube of said first metal, the first tube having a solid tube section and a first spiral cut-out section;
a second hollow tube piece substantially comprised of a second metal, said second hollow tube piece is a second tube of said second metal, the second tube having a solid tube section and a second spiral cut-out section, wherein the first spiral cut-out section and the second spiral cut-out section define a spiral space therebetween;
said first metal is different from and more flexible at human body temperature than said second metal;
a third hollow piece substantially comprised of a radiopaque material, said third hollow piece being within said spiral space such that the first spiral cut-out section, the second spiral cut-out section and the third hollow piece within the spiral space form a joint longitudinally between the first hollow tube piece and the second hollow tube piece;
said first and second spiral cut-out sections have substantially identical outer diameters and substantially identical inner diameters, said third hollow piece has an outer diameter no greater than said outer diameter of the cut-out sections, and said third hollow piece has an inner diameter no smaller than said inner diameter of the cut-out sections;
the joint further includes a shrink tubing along said spiral cut-out sections and said third hollow piece, and the shrink tubing adheres together the first and second hollow tube pieces so as to seal together the first and second cut-out sections along with said third hollow piece.
2. The article of claim 1 , wherein said first metal has superelastic properties.
3. The article of claim 1 , wherein said first metal is a nitinol material.
4. The article of claim 1 , wherein said first metal is a nitiriol material and said second metal is stainless steel.