Limb for breathing circuit

Patent metadata

Field	Value
Publication number	US-9533117-B2
Application number	US-201414477608-A
Country	US
Kind code	B2
Filing date	Sep 4, 2014
Priority date	Sep 9, 2002
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A limb for a breathing circuit manufactured from very thin walled polymer materials has an elongate axial reinforcing spine lying freely inside the conduit and fixed to each end connector. The spine is laterally compliant but axially stiff. The spine provides resistance to tensile and compressive loads on the conduit, including that induced by prevailing internal pressures.

First claim

The invention claimed is:

1. A limb for a breathing circuit comprising:
a flexible conduit having a first end and a second end and a breathing gases pathway therebetween, said flexible conduit formed using a film having a thickness less than 50 μm,
a first connector fixed to said first end of said flexible conduit,
a second connector fixed to said second end of said flexible conduit, and
an elongate reinforcing member lying freely within said flexible conduit along a non-tortuous path from one end of said flexible conduit to the other end of said flexible conduit, and connected with said first connector and said second connector, such that said elongate reinforcing member reinforces said flexible conduit against contraction along the length of said flexible conduit due to fluctuating internal pressure, and
wherein said elongate reinforcing member has a cross sectional area, measured from the outer perimeter, less than 10% of the cross sectional area of the bore of said flexible conduit.

2. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member does not include a passageway large enough for gases delivery to a patient.

3. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member is hollow, and said hollow elongate reinforcing member is blind terminated at each end by said first connector and said second connector.

4. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member has a solid, substantially circular cross section, and two ends.

5. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member includes a positive temperature coefficient heating element.

6. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member includes a resistance heating element.

7. A limb for a breathing circuit as claimed in claim 1 , wherein the length of said elongate reinforcing member is between 100.5% and 105% of the length of said flexible conduit.

8. A limb for a breathing circuit as claimed in claim 1 , wherein said limb includes a helical rib and a first end suitable for making connection with auxiliary equipment and a second end for making connection with a breathing conduit, and
an annular shoulder between said first end and said second end,
said second end extending along an axis and having a substantially circular cross section, and
said second end having at least one protrusion on an outer surface for interlocking engagement with said helical rib.

9. A limb for a breathing circuit as claimed in claim 8 , wherein said protrusion is an external thread having a pitch suitable for engagement with said helical rib.

10. A limb for a breathing circuit as claimed in claim 9 , wherein said shoulder portion has an annular recess for receiving a securing collar having an extrusion axis.

11. A limb for a breathing circuit as claimed in claim 10 , wherein said securing collar has a recess substantially parallel with said extrusion axis for receiving said elongate reinforcing member.

12. A limb for a breathing circuit as claimed in claim 8 , wherein said second end has a recess substantially parallel with said axis for receiving said elongate reinforcing member.

13. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member is resilient and does not plastically deform in use, under normal flexing and bending of said limb.

14. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member has a cross sectional area between 3 mm 2 and 12.5 mm 2 .

15. A limb for a breathing circuit as claimed in claim 1 , wherein said elongate reinforcing member has a minimum bending stiffness between 693 N·mm 2 and 11096 N·mm 2 .

16. A limb for a breathing circuit as claimed in claim 1 , further comprising:
a sheath surrounding said flexible conduit and being fixed at and around one end to said first connector and at and around its other end to said second connector.

17. A limb for a breathing circuit as claimed in claim 16 , wherein said sheath is braided.

18. A limb for a breathing circuit as claimed in claim 17 , wherein said sheath is braided from polyethylene terephthalate monofilaments.

19. A method for manufacturing a limb for a breathing circuit comprising:
providing a conduit having a first end and a second end, said flexible conduit formed using a film having a thickness less than 50 μm,
locating an elongate reinforcing member having a first end and a second end, lying freely within said flexible conduit, along a non-tortuous path from one end of said flexible conduit to the other end of said flexible conduit, said elongate reinforcing member having a cross sectional area, measured from the outer perimeter, less than 10% of the cross sectional area of the bore of said flexible conduit,
fixing a first end connector with said first end of said flexible conduit, and said first end of said elongate reinforcing member, and
fixing a second end connector with said second end of said flexible conduit and said second end of said elongate reinforcing member, such that said elongate reinforcing member reinforces said flexible conduit against contraction along the length of said flexible conduit due to fluctuating internal pressure.

20. A method for manufacturing a limb for a breathing circuit as claimed in claim 19 , further including:
locating a reinforcing mesh having a first and a second end, over the outside of said flexible conduit,
fixing said first end connector with said first end of said flexible conduit, and said first end of said reinforcing mesh, and
fixing said second end connector with said second end of said flexible conduit and said second end of said reinforcing mesh.

Assignees

• Fisher & Paykel Healthcare Ltd

Inventors

• Gray Nathan Lee

Classifications

• B29C66/4322

  by joining a single sheet to itself (B29C66/4332 takes precedence) · CPC title

• B29C66/4329

  the joint lines being transversal but non-orthogonal with respect to the axis of said tubular articles, i.e. being oblique · CPC title

• B29C66/1122

  Single lap to lap joints, i.e. overlap joints (B29C66/45, B29C66/472, B29C66/52272 take precedence) · CPC title

• F16L11/115

  having reinforcements not embedded in the wall · CPC title

• A61M16/0816

  Joints or connectors · CPC title