Flexible medical tubing having kink resistant properties and methods and apparatus to produce the same

Patent metadata

Field	Value
Publication number	US-9399113-B2
Application number	US-201213674246-A
Country	US
Kind code	B2
Filing date	Nov 12, 2012
Priority date	Sep 16, 2010
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

A method is provided for making a tubing, which includes forming a generally tubular inner layer by flowing a first material through an extrusion assembly. At least one non-tubular segment is formed along the length of the tubing by flowing a second material through the extrusion assembly. A generally tubular outer layer coaxial with the inner layer is formed by flowing a third material through the extrusion assembly. The segment is positioned between the inner and outer layers and oriented non-tangentially with an interface between the inner and outer layers. The resulting tubing, which may be suitable for medical applications, may have kink-resistant properties.

First claim

The invention claimed is:

1. A method for making a tubing comprising:
forming a generally tubular inner layer by flowing a first material through an extrusion assembly;
forming at least one non-tubular segment along the length of the tubing by flowing a second material through the extrusion assembly; and
forming a generally tubular outer layer coaxial with the inner layer by flowing a third material through the extrusion assembly, wherein said at least one segment is positioned between the inner and outer layers and oriented non-tangentially with an interface between the inner and outer layers.

2. The method of claim 1 , wherein said forming a generally tubular inner layer includes inducing a helical rotational flow of the first material flowing through the extrusion assembly.

3. The method of claim 1 , wherein said forming at least one non-tubular segment includes forming at least one helical segment.

4. The method of claim 1 , wherein said first and third materials are different.

5. The method of claim 4 , further comprising introducing the first, second, and third materials into the extrusion assembly using three material inlets.

6. The method of claim 1 , wherein said first and third materials are the same.

7. The method of claim 6 , further comprising introducing the first and third materials into the extrusion assembly using a single material inlet.

8. The method of claim 7 , further comprising providing the extrusion assembly with a flow splitter downstream of the single material inlet and flowing the first and third materials around the flow splitter.

9. The method of claim 1 , wherein said forming at least one non-tubular segment includes forming a plurality of non-tubular segments.

10. The method of claim 1 , wherein at least one of said materials comprises a non-PVC material.

Assignees

• Fenwal Inc

Inventors

• Sandford Craig
• Marshall Dean R
• Boggs Daniel R
• Peralta-Faulkner Alvin
• Calhoun Daryl

Classifications

• B29L2031/7732

  Helical (springs B29L2031/774) · CPC title

• B29C48/09

  Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels · CPC title

• A61M25/005 Primary

  with embedded materials for reinforcement, e.g. wires, coils, braids · CPC title

• B29C48/33

  with parts rotatable relative to each other · CPC title

• B29L2031/7542

  Catheters · CPC title