US 12,222,128 B2
Sound absorbing duct for environmental control system
Bryce A. Vandyke, Snohomish, WA (US); John Erik West, Seattle, WA (US); Douglas D. Maben, Snohomish, WA (US); Andrew K. Fung, Everett, WA (US); and David R. C. Cannal, Marysville, WA (US)
Assigned to The Boeing Company, Arlington, VA (US)
Filed by THE BOEING COMPANY, Arlington, VA (US)
Filed on Jul. 3, 2023, as Appl. No. 18/346,447.
Application 18/346,447 is a division of application No. 16/105,864, filed on Aug. 20, 2018, granted, now 11,739,973.
Prior Publication US 2023/0358433 A1, Nov. 9, 2023
Int. Cl. F24F 13/02 (2006.01); B64D 13/06 (2006.01); F24F 13/24 (2006.01)
CPC F24F 13/0263 (2013.01) [B64D 2013/0603 (2013.01); F24F 13/0245 (2013.01); F24F 13/0281 (2013.01); F24F 2013/242 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A duct comprising:
a rigid tube of composite material;
an insulation layer disposed within the rigid tube; and
a biasing member disposed within the rigid tube, the biasing member configured to restrain the insulation layer against an interior surface of the rigid tube, wherein the insulation layer is coupled to the biasing member by the biasing member being threaded through the insulation layer.