PLIABLE-WALL AIR DUCTS WITH INTERNAL EXPANDING STRUCTURES

• US 20140261835A1
• Filed: 05/27/2014
• Published: 09/18/2014
• Est. Priority Date: 11/19/2010
• Status: Active Grant

• Current Assignee: Rite-Hite Holding Corporation
• Original Assignee: Rite-Hite Holding Corporation
• Inventors: Pinkalla, Cary, Heim, Frank, Gebke, Kevin J., Kaufmann, Nicholas L., Niehaus, William A.
• Granted Patent: US 9,605,865 B2
• Time in Patent Office: Days
• US Class Current: 138/107
• CPC Class Codes: F16L 11/00 Hoses, i.e. flexible pipes
• CPC Class Codes: F16L 11/02 made of fibres or threads, e.g. of textile which may or may not be impregnated, or provided with an impermeable layer, e.g. fire-hoses
• CPC Class Codes: F16L 11/10 with reinforcements not embedded in the wall F16L11/11 takes precedence
• CPC Class Codes: F16L 3/18 allowing movement in axial direction
• CPC Class Codes: F16L 55/00 Devices or appurtenances for use in, or in connection with, pipes or pipe systems the preceding groups and groups F16L57/00, F16L59/00 take precedence; repairing or joining pipes on or under water F16L1/26; nozzles B05B; cleaning of pipes B08B9/02; arrangements of draining devices for water main or service pipe systems E03B7/08; devices for preventing bursting of water pipes by freezing E03B7/10; draining devices for hydrants E03B9/14; for domestic plumbing installations E03C1/00; steam traps for draining of liquids from enclosures containing gases or vapours F16T; arrangements for sealing leaky tubes or conduits of heat-exchangers F28F11/00
• CPC Class Codes: F24F 13/0218 Flexible soft ducts, e.g. ducts made of permeable textiles
• CPC Class Codes: F24F 13/0245 Manufacturing or assembly of air ducts; Methods therefor
• CPC Class Codes: F24F 13/0254 characterised by their mounting means, e.g. supports
• CPC Class Codes: F24F 2221/26 improving the aesthetic appearance
• CPC Class Codes: F24F 7/06 with forced air circulation, e.g. by fan positioning of a ventilator in or against a conduit
• CPC Class Codes: F24F 7/065 fan combined with single duct; mounting arrangements of a fan in a duct
• CPC Class Codes: Y10T 137/0402 Cleaning, repairing, or assembling
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

Example air ducts comprising pliable tubular sidewalls are provided with example internal frameworks that hold the duct in a generally expanded shape even when the duct is depressurized. The framework tensions the pliable sidewall material along the length of the ducts to keep the material taut. In some examples, the framework is restrained within the duct such that the duct'"'"'s sidewall, being in tension, holds the framework in compression longitudinally. Thus, in the longitudinal direction, the duct is in tension and the framework is in compression. To prevent the framework from buckling under the compressive force, some example frameworks comprise a central longitudinal shaft with a plurality of radial spokes and rings that help hold the shaft straight. In some examples, the rings also help hold the duct radially expanded.

Claims

1. An air duct system, comprising:

an air duct having a tubular shape; and

a framework disposed inside and coupled to the air duct, the framework comprising a material of less flexibility than that of the air duct, the framework being adjustable along a length of the air duct, and the air duct being in tension along the length of the air duct.

2. The air duct system of claim 1, wherein the framework comprises a shaft extending along the length of the air duct, the shaft being in compression to hold the air duct in tension.

3. The air duct system of claim 1, wherein the air duct includes an elbow.

4. An air duct system for handling air selectively at an active air pressure and at an inactive ambient air pressure, the air duct system comprising:

an air duct having a tubular shape to define a longitudinal direction, the air duct comprising a pliable sidewall; and

a framework disposed inside the air duct, the air duct being held in tension in the longitudinal direction by virtue of the framework being held in compression in the longitudinal direction.

5. The air duct system of claim 4, wherein the pliable sidewall is more flexible than the framework.

6. The air duct system of claim 4, wherein the air duct is at a first magnitude of tension in the longitudinal direction when the air inside the air duct is at the inactive ambient air pressure, the air duct is at a second magnitude of tension in the longitudinal direction when the air inside the air duct is at the active positive air pressure, and the first magnitude of tension being less than the second magnitude of tension.

7. The air duct system of claim 4, wherein the framework is at a first magnitude of compression in the longitudinal direction when the air inside the air duct is at the inactive ambient air pressure, the framework is at a second magnitude of compression in the longitudinal direction when the air inside the air duct is at the active positive air pressure, and the first magnitude of compression being greater than the second magnitude of compression.

8. The air duct system of claim 4, wherein the framework is supported by the air duct.

9. The air duct system of claim 4, further comprising an overhead support structure from which the air duct is suspended independent of the framework.

10. The air duct system of claim 4, further comprising an overhead support structure to which both the air duct and the framework are independently connected.

11. The air duct system of claim 4, wherein the framework has a longitudinally adjustable length.

12. An air duct system for supporting a tubular pliable sidewall, the air duct system comprising:

a tubular pliable side wall defining a flow direction along which the air duct system conveys a current of air;

a ring disposed within the tubular pliable side wall and lying substantially perpendicular to the flow direction;

a hub disposed substantially at a center point of the ring, the hub extending lengthwise in the flow direction; and

a plurality of spokes extending between the ring and the hub, the plurality of spokes being attached to the hub at a plurality of points that are distributed lengthwise along the hub, the air duct being in tension along the flow direction of the air duct.

13. The air duct system of claim 12, further comprising:

a second ring disposed within the tubular pliable side wall spaced apart from the ring;

a second hub disposed substantially at a center point of the second ring; and

a shaft extending between the hub and the second hub, the shaft to hold the air duct in tension.

14. The air duct system of claim 12, wherein the tubular pliable sidewall forms an elbow duct.

15. A method of retrofitting an existing air duct system that includes an inflatable air duct for conveying air in a longitudinal direction through an interior volume of the inflatable air duct, the method comprising:

accessing the interior volume of the inflatable air duct;

installing a framework within the interior volume of the inflatable air duct;

coupling the framework to the inflatable air duct; and

in the longitudinal direction, applying force to the framework and tensioning the inflatable air duct by virtue of the framework being installed within the interior volume of the inflatable air duct.

16. The method of claim 15, wherein the framework has a total weight that is supported by the air duct.

17. The method of claim 15, further comprising suspending the inflatable air duct without load-carrying assistance from the framework.

18. An air duct system, comprising:

a tubular air duct being comprising a pliable sidewall;

a first ring movably coupled to a first shaft, the first ring and the first shaft to be disposed within the air duct, the first ring to be movable relative to the first shaft to place the air duct in tension.

19. The air duct system of claim 18, further comprising a second ring movably coupled to a second shaft, the second ring and the second shaft to be disposed within the air duct, the second ring movable relative to the second shaft to place the air duct in tension.

20. The air duct system of claim 19, wherein the first ring is spaced from the second ring.

21. The air duct system of claim 19, wherein the first shaft is coupled to the second shaft.

22. The air duct system of claim 18, further comprising a hub and a spoke, the spoke coupling the hub and the first ring, the hub coupled to the first shaft.

23. The air duct system of claim 18, further comprising a spoke coupling the first ring and the first shaft.

24. The air duct system of claim 23, wherein the spoke is non-perpendicularly coupled to the first shaft.

25. The air duct system of claim 24, wherein the ring is coupled to an interior surface of the air duct.

26. The air duct system of claim 18, wherein the coupling between the ring and the interior surface enables the ring to be resistive to compressive forces.

27. The air duct system of claim 18, wherein the first ring is telescopically coupled to the first shaft.