Abstract: Pliable air ducts with anti-condensation nozzles are disclosed. An example system includes a tubular duct comprising a pliable wall dividing an interior of the tubular duct from an exterior of the tubular duct. The system includes an outlet member to be attached to the pliable wall. The outlet member defines a main air passageway with a first flow resistance therethrough and places the interior of the tubular duct in fluid communication with the exterior of the tubular duct. The system includes a secondary air passageway with a second flow resistance therethrough. The secondary air passageway is defined by at least one of the outlet member or the pliable wall and extends from the interior of the tubular duct to the exterior of the tubular duct to define an airflow path proximate the outlet member. The second flow resistance is significantly greater than the first flow resistance.

Abstract: Example inflatable air barriers are disclosed herein. Some example barriers disclosed herein include one or more inflatable tubes for maintaining a sealed airlock leading to an underground shelter. Such shelters provide miners with temporary refuge in the event of a mining incident involving the release of contaminated air. Some example barriers disclosed herein include one or more of the following: an inflatable tube with an air permeable section, a resiliently compressible foam body or other resilient member for supporting a deflated tube, a magnet for providing a secure seal, an inflatable tube with interchangeable end caps, elastic bands for securing the position of an inflatable tube, or an inflatable tube with one or more windows.

Abstract: Example methods, apparatus, and articles of manufacture to determine pliable air duct configurations are disclosed. A disclosed example method involves determining a first quantity of adjustable air outlet duct sections to configure an air delivery duct system when an operating mode identifier is received. The operating mode identifier is associated with an amount of air delivered by the air delivery duct system into targeted areas. The first quantity of adjustable air outlet duct sections is based on an airflow rate value and the operating mode identifier. The airflow rate value is indicative of airflow through an air delivery duct system. Each adjustable air outlet duct section includes at least one adjustable air outlet having at least one size-adjustable orifice.

Abstract: Pliable-wall air ducts with internal expanding structures are disclosed. An example air duct system includes a shaft to be disposed within an air duct, to extend in a longitudinal direction, and to be in longitudinal compression. The air duct system also includes a plurality of ribs to be coupled to the shaft and to engage an inner surface of the air duct and a spring to be disposed within the air duct, the spring to be coupled to the shaft. The spring under stress being a contributing factor in both the shaft being in longitudinal compression and the air duct being in longitudinal tension.

Abstract: Pliable-wall air ducts with internal expanding structures are disclosed. An example air duct system includes a shaft to be disposed within an air duct, to extend in a longitudinal direction, and to be in longitudinal compression. The air duct system also includes a plurality of ribs to be coupled to the shaft and to engage an inner surface of the air duct and a spring to be disposed within the air duct, the spring to be coupled to the shaft. The spring under stress being a contributing factor in both the shaft being in longitudinal compression and the air duct being in longitudinal tension.

Abstract: Pliable-wall air ducts with suspended frames are disclosed herein. An example air duct system includes an air duct having a pliable sidewall to extend in a longitudinal direction, the pliable sidewall having a total weight and a framework to be disposed within the air duct. The framework includes a shaft extending in the longitudinal direction, a rib to engage an inner surface of the air duct and a plurality of spokes connecting the rib to the shaft. The example air duct system includes one or more hangers comprising an elongate member having an upper section and a lower section. The lower section to extend through a corresponding opening defined by the pliable side wall and to be coupled to the framework. Most of the total weight of the pliable sidewall is to be carried by the framework.

Abstract: Pliable-wall air ducts with suspended frames are disclosed herein. An example air duct system includes an air duct having a pliable sidewall to extend in a longitudinal direction, the pliable sidewall having a total weight and a framework to be disposed within the air duct. The framework includes a shaft extending in the longitudinal direction, a rib to engage an inner surface of the air duct and a plurality of spokes connecting the rib to the shaft. The example air duct system includes one or more hangers comprising an elongate member having an upper section and a lower section. The lower section to extend through a corresponding opening defined by the pliable side wall and to be coupled to the framework. Most of the total weight of the pliable sidewall is to be carried by the framework.

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.

Abstract: Example air duct systems for supplying conditioned air to comfort zones include various example inflatable tubes with various example dampers. The dampers move noticeably slowly and/or its opening is delayed to reduce the rate at which the tube is inflated by a supply air blower. Depending on the particular example, the damper can be either at the inlet end of the tube or at the tube's opposite end. In some examples, the damper is controlled by an actuator that is powered by air or driven by an electric motor.

Abstract: In some example pliable air duct systems, inflatable ducts of various diameters and lengths are created by selectively assembling pre-existing stock pieces in different combinations. In some examples, the stock pieces include disconnectable longitudinal joints and disconnectable circumferential joints, wherein the longitudinal joints enable interconnecting multiple stock pieces to achieve a desired tube diameter, and the circumferential joints allow connecting multiple tube segments end-to-end to produce an air duct assembly of a desired length. To control the volume and/or the direction of air discharged from the duct, the duct assembly, in some examples, includes an adjustable register comprising a movable pliable sheet that overlies a discharge opening in a pliable sidewall of the duct. In some examples, the inflatable duct includes one or more cutout patterns on the duct's sidewall to provide guidance in creating a sidewall discharge opening of a proper size and location.

Abstract: Example methods, apparatus, and articles of manufacture to determine pliable air duct configurations are disclosed. A disclosed example method involves determining a first quantity of adjustable air outlet duct sections to configure an air delivery duct system when an operating mode identifier is received. The operating mode identifier is associated with an amount of air delivered by the air delivery duct system into targeted areas. The first quantity of adjustable air outlet duct sections is based on an airflow rate value and the operating mode identifier. The airflow rate value is indicative of airflow through an air delivery duct system. Each adjustable air outlet duct section includes at least one adjustable air outlet having at least one size-adjustable orifice.

Abstract: In some example pliable air duct systems, inflatable ducts of various diameters and lengths are created by selectively assembling pre-existing stock pieces in different combinations. In some examples, the stock pieces include disconnectable longitudinal joints and disconnectable circumferential joints, wherein the longitudinal joints enable interconnecting multiple stock pieces to achieve a desired tube diameter, and the circumferential joints allow connecting multiple tube segments end-to-end to produce an air duct assembly of a desired length. To control the volume and/or the direction of air discharged from the duct, the duct assembly, in some examples, includes an adjustable register comprising a movable pliable sheet that overlies a discharge opening in a pliable sidewall of the duct. In some examples, the inflatable duct includes one or more cutout patterns on the duct's sidewall to provide guidance in creating a sidewall discharge opening of a proper size and location.

Abstract: An under-floor HVAC system for a building includes a pliable air duct lying upon a subfloor. A matrix of pedestals resting upon and extending upward from the subfloor supports a set of floor panels, which thus creates a plenum between the subfloor and the set of floor panels. The air duct extends through the plenum to convey conditioned air from a supply air duct to a series of registers in the floor panels. The registers disperse the conditioned air to a room or area just above the panels. To help keep the air duct from repeatedly extending, retracting, and otherwise sliding freely along the subfloor in response to changes in air duct pressure, the air duct is held taut by anchoring a distal downstream end of the duct to one or more of the floor-supporting pedestals. Various air duct configurations can be assembled from a predefined assortment of duct components.

Abstract: An air duct assembly includes upper and lower pliable sheets that can be assembled in a sequence that makes the assembly easier to install and later easier to remove for periodic cleaning. To install the assembly, the upper sheet can be installed first by inserting the edges of the upper sheet within a pair of tracks and then fastening the upper sheet to a vertical supply air duct. An optional airflow modifier (e.g., filter, airflow turning vane, or noise attenuator) can be install where the supply air duct connects to the upper sheet. Once the upper sheet is suspended from the tracks and fastened to the main supply air duct, the lower sheet can be installed separately. Pliable end panels and pliable fasteners (e.g., zipper or VELCRO fastener) can make most of the air duct assembly machine washable. The upper and lower sheets can have different degrees of air permeability.

Abstract: A door for a cold storage locker or other applications includes an inflatable or fluid-filled seal system. The seal system comprises a network of pliable tubular seals that expand as air or another fluid is forced air through the seals. Expansion of the seals provides a more positive seal. To inhibit frost from accumulating near the seals, the seals are kept relatively warm by continuously circulating fluid through the seals regardless of whether the door is open or closed. In some cases, the fluid within the seals is heated.

Abstract: An air diffuser includes a porous fabric panel having areas of different flow coefficients. The areas' positions and their relative flow coefficients provide a means for not only diffusing the air but also for strategically directing the airflow in a deliberate pattern that promotes intermixing of the air while avoiding adverse air currents. Consequently, the porous fabric itself provides air dispersion and airflow direction without the need for louvers or guide vanes. In some embodiments, the fabric's porosity is programmed by laser cutting small slits into the fabric.

Abstract: An external suspension system for supporting an inflatable air duct includes a series of external hangers that help hold the duct open while the duct is deflated. In some embodiments, the suspension system supports the duct at a series of points that are broadly distributed in a staggered pattern across the duct, yet the entire duct can be suspended from a single overhead cable, even if the duct is a stepped tube with multiple diameters. The system includes novel ways of locking the hangers to the duct and to the overhead cable.

Abstract: A fabric air duct of an HVAC system includes a discharge air register with an air deflector that extends along the length of the duct. Rotating or twisting the deflector adjusts the volume and/or direction of the air being discharged from the register. Even though the deflector is disposed inside the duct, the deflector can be twisted or rotated by manipulating the exterior fabric wall of the duct.

Abstract: A fabric air duct with main discharge openings includes additional, much smaller openings that help ventilate the surface of the duct. Ventilating the surface of the duct with a slight yet even amount of airflow helps inhibit the accumulation of condensate and dust on the surface of the duct. In some embodiments, the duct includes a pliable sheet consisting of a rather porous fabric base material. To achieve an appropriately low level of airflow, a plastic coating on the fabric reduces, but does not eliminate the fabric's porosity. A calendering process then reduces the porosity even further. In some embodiments, the calendering process occurs before the plastic coating process. In other embodiments, the pliable sheet is substantially air impermeable, except for its main discharge openings. The sheet is then perforated with numerous smaller openings to achieve the desired amount of surface ventilation.

Abstract: A fabric flow restriction and method for conveying a volume of air through a fabric duct prevents the violet popping that may occur with a fabric duct upon start-up. The fabric ducts are air permeable and/or include discharge openings that evenly disperse supply air from within the duct to a room being heated, cooled, ventilated, or otherwise conditioned by the air. The ducts are typically in a collapsed positioned prior to blower start-up. With the initial airflow, the ducts quickly fill with air and may make a popping sound at their distal ends as the airflow fills the entire fabric duct. The flow restrictions disclosed may be formed of a flexible fabric that has an airflow resistance that varies with radius across the flexible fabric. The flow restrictions may have a first region and a second region each with different resistances, for example. Varying the resistance across the fabric flow restriction reduces or eliminates the popping condition.