Medical tubing having variable characteristics and method of making same
View Patent ↗The invention primarily is directed to a medical tubing adapted for insertion into a body tissue or cavity and method of manufacturing different variations of the tubing along a length of the tubing. The tubing comprises a plurality of individual, discrete, generally ring-shaped elements arranged in series and fused or bonded together forming a continuous tubular structure. The ring-shaped elements may include a combination of flexible and rigid ring-shaped elements assembled along different portions or sections of the tubular structure. In another aspect of the invention, the medical tubing may further comprise a secondary lumen and a pull wire to control the tubular structure. In another aspect of the invention, the ring-shaped elements may vary in diameter and/or composition in different portions or sections of the tubular structure.
1. A method of manufacturing a medical tubing having a length with variable characteristics, the medical tubing comprising a plurality of individual, discrete, generally ring-shaped elements arranged in series and fused together to form a continuous tubular structure, the method comprising the steps of:
providing a plurality of ring-shaped elements; each ring-shaped element having an aperture located between an inner diameter and an outer diameter;
passing a wire through the aperture of each ring-shaped element along a support member or mandrel such that the wire is adjacent to the inner circumference of the plurality of ring-shaped elements and the longitudinal axis of the wire is parallel to the longitudinal axis of the support member or mandrel;
placing the plurality of ring-shaped elements upon the support member or mandrel in a series arrangement;
heating the plurality of ring-shaped elements and wire to fuse the rings over the wire and support member or mandrel; and
removing the support member or mandrel.
2. The method of claim 1 , wherein the step of placing the plurality of ring-shaped elements includes placing the plurality of ring-shaped elements upon the wire before the heating step.
3. The method of claim 1 , further comprising forming a control tube over the assembled ring-shaped elements prior to the heating step.
4. The method of claim 3 , wherein the control tube comprises at least one of glass, silicone, heat shrinkable polyolefin, PTFE, FEP, metallic or other tubing that has a higher melting temperature than the assembled ring-shaped elements.
5. The method of claim 1 wherein the ring-shaped elements have either an inner diameter or an outer diameter comprised of thermoplastic or thermoset material.
6. The method of claim 1 further including the step of removing the wire.
7. The method of claim 1 wherein the step of placing the plurality of ring-shaped elements includes placing ring-shaped elements having different lengths.
8. The method of claim 1 wherein the step of heating the plurality of ring-shaped elements includes fusing the ring-shaped elements closer or further apart.
9. The method of claim 1 further including the step of providing a pull wire.
10. The method of claim 1 wherein the step of heating the plurality of ring-shaped elements and wire includes the step of heating the plurality of ring-shaped elements to fuse the rings over the wire and support member or mandrel to form a first lumen and a second lumen.