Conduit and method of forming

Patent metadata

Field	Value
Publication number	US-10828456-B2
Application number	US-201715634934-A
Country	US
Kind code	B2
Filing date	Jun 27, 2017
Priority date	Sep 9, 2002
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

A thin ribbon spirally wound polymer conduit and method of forming, wherein a helical reinforcing bead is interposed adjacent overlapping layers of ribbon. Further, a method of continuously forming spirally wound conduit wherein a sacrificial layer, preferably having a different base polymer to that of the conduit, is first applied to the former before the conduit is formed overtop.

First claim

The invention claimed is:

1. An apparatus for continuously forming conduit, the apparatus comprising:
a former configured to receive at least one ribbon, and to draw the ribbon around and advance the ribbon along to form a helical arrangement of the ribbon, a pitch of the helical arrangement being less than width of the ribbon,
a first assembly configured to deliver a first ribbon comprising a plastic material to the former at a first position on the former,
a second assembly configured to deliver continuously a molten bead to the former at a second position less than one turn pitch from the first position of delivery of the first ribbon, the second position corresponding to an expected position of a trailing edge of the first ribbon delivered by the first assembly, and
a reel configured to deliver a sacrificial layer to the former in an overlapping pattern at a third position, wherein the third position is located in front of the first position so that the sacrificial layer is delivered to the former before the first ribbon is delivered to the former.

2. The apparatus for continuously forming conduit of claim 1 , wherein the first ribbon comprises a leading lateral edge and a trailing lateral edge, and the former is configured to arrange the first ribbon in spiral turns such that, at a first spiral turn, the leading lateral edge overlaps the trailing lateral edge adjacent a previous spiral turn, and the trailing lateral edge underlaps the leading lateral edge adjacent a succeeding spiral turn.

3. The apparatus for continuously forming conduit of claim 2 , an extent of the leading lateral edge over the trailing lateral edge defining an overlapping portion and an extent of the trailing lateral edge under the leading lateral edge defining an underlapping portion,
wherein the second assembly is configured to interpose helically the molten bead between the overlapping portion of the first ribbon and the underlapping portion of the first ribbon.

4. The apparatus for continuously forming conduit of claim 3 , the molten bead comprising a first edge and a second edge,
wherein the second assembly is configured to deliver the molten bead such that the molten bead, when cooled, comprises:
a first portion, comprising a flat portion having a flat profile in cross-section, proximal the underlapping portion of the first ribbon and comprising a first edge and a second edge, and
a second portion, having a contour profile in cross-section, proximal the overlapping portion of the first ribbon and extending between the first edge and the second edge of the first portion of the cooled bead.

5. The apparatus for continuously forming conduit of claim 4 , wherein the leading lateral edge of the first ribbon meets the underlapping portion of the first ribbon at the first edge of the first portion of the cooled bead.

6. The apparatus for continuously forming conduit of claim 4 , wherein the leading lateral edge of the first ribbon meets the underlapping portion of the first ribbon at the first edge of the first portion of the cooled bead.

7. The apparatus for continuously forming conduit of claim 1 , wherein the first assembly comprises an extruder.

8. The apparatus for continuously forming conduit of claim 1 , wherein the molten bead comprises a plastic material.

9. The apparatus for continuously forming conduit of claim 1 , wherein the plastic material of the first ribbon is breathable, such that, when the conduit is in use, the plastic material of the first ribbon allows passage of water vapor from a respiratory gas flowing within the conduit.

10. The apparatus for continuously forming conduit of claim 1 , wherein the second assembly comprises an extruder.

11. The apparatus for continuously forming conduit of claim 1 , wherein the first ribbon has a thickness of less than about 50 microns.

12. The apparatus for continuously forming conduit of claim 1 , further comprising a third assembly configured to deliver a pair of spaced apart heater wires in between adjacent turns of the helical arrangement of the ribbon and in a position that will be overlaid by the molten bead from the second assembly.

13. An apparatus for continuously forming conduit, comprising:
a former configured to receive a ribbon, the former configured to draw the ribbon around and advance the ribbon along, to form an overlapping helical arrangement of the ribbon, pitch of the helical arrangement being less than width of the ribbon,
a first assembly configured to deliver a first ribbon to the former, at a first location,
a second assembly configured to deliver a second ribbon to the former, at a location after the first ribbon,
a bead assembly configured to continuously deliver a molten reinforcement bead to the former at a position less than one turn pitch from a position of delivery of the second ribbon, the position corresponding to an expected position of a trailing edge of the second ribbon, wherein the molten reinforcement bead is configured to provide reinforcement to the conduit, and
a reel configured to deliver a sacrificial layer to the former in an overlapping pattern at a third position, wherein the third position is located in front of the first position so that the sacrificial layer is delivered to the former before the first ribbon is delivered to the former;
wherein the first ribbon and the second ribbon each have a thickness of less than about 50 microns.

14. The apparatus for continuously forming conduit of claim 13 , wherein the apparatus is configured such that no material is applied outside of the first ribbon before the first ribbon is overlaid by the second ribbon.

15. The apparatus for continuously forming conduit of claim 13 , wherein the second ribbon comprises a leading lateral edge and a trailing lateral edge, and the former is configured to arrange the second ribbon in spiral turns such that, at a first spiral turn, the leading lateral edge overlaps the trailing lateral edge adjacent a previous spiral turn, and the trailing lateral edge underlaps the leading lateral edge adjacent a succeeding spiral turn.

16. The apparatus for continuously forming conduit of claim 15 , an extent of the leading lateral edge over the trailing lateral edge defining an overlapping portion and an extent of the trailing lateral edge under the leading lateral edge defining an underlapping portion, and the molten reinforcement bead comprising a first edge and a second edge,
wherein the bead assembly is configured to deliver the molten reinforcement bead such that the molten reinforcement bead, when cooled, comprises
a first portion, comprising a flat portion having a flat profile in cross-section, proximal the underlapping portion of the second ribbon and comprising a first edge and a second edge, and
a second portion, having a contour profile in cross-section, proximal the overlapping portion of the second ribbon and extending continuously between the first edge and the second edge of the first portion of the cooled reinforcement bead.

17. The apparatus for continuously forming conduit of claim 16 , wherein the extent of the overlapping portion of the second ribbon conforming around the full perimeter of the second portion of the helical reinforcement bead defines a conforming portion that is bonded to the cooled reinforcement bead along the conforming portion.

18. The apparatus for continuously forming conduit of claim 13 , wherein the second ribbon comprises a breathable plastic material that, when the conduit is in use, allows passage of water vapor from a respiratory gas flowing within the cond

Assignees

• Fisher & Paykel Healthcare Ltd
• Fisher & Paykel Heathcare Ltd

Inventors

• Smith Daniel John
• Gray Nathan Lee
• Skelton Blair Victor

Classifications

• A61M2207/10

  Device therefor · CPC title

• A61M16/1095

  in the connecting tubes · CPC title

• A61M11/08 Primary

  Pocket atomisers of the injector type {(aerosol cans A61M15/009)} · CPC title

• B29C66/723

  being multi-layered (B29C66/7292, B29C66/72941 take precedence) · CPC title

• B29C65/40

  Applying molten plastics, e.g. hot melt (using welding bar {combined with hot gases} B29C65/12; by moulding B29C65/70) · CPC title