Patent Application
20130061975
None.
I. Field of the Invention
The present disclosure relates generally to an air supply hose assembly. In particular, the present disclosure is directed to an air supply hose assembly for supplying pre-cooled air to an on-ground aircraft.
II. Description of the Prior Art
Aircraft on the ground powered up for repair or replenishment often require conditioned air to cool the pilot and to maintain electronics and other support equipment at desired temperatures. Such conditioned air is typically supplied by a ground support cart which is positioned in close proximity to the aircraft. The ground support cart is connected to the aircraft by means of a flexible duct or hose.
Conventional prior design flexible hose assemblies for ground support consist of an impermeable inner liner forming a conduit for the air, a closed cell insulation layer surrounding the inner liner to minimize warming of air passing through the conduit, and an outer liner to protect the insulation layer. Most of these current aircraft supply hose assemblies evolved from air supply hose assemblies used for civilian aircraft that operate at relatively low pressures and small temperature ranges, and therefore have not been satisfactory for military aircraft which require substantially higher pressures and wider temperature ranges. When preconditioned air is forced from a ground support cart to a military aircraft through prior design air supply hose assemblies at higher pressures, the inner liner of the supply hose expands under the pressure and compresses the insulation, resulting in a loss of insulation efficiency and consequent increased warming of the conditioned air as it passes through the hose assembly.
Accordingly, it is a general object of the present disclosure to provide a ground support hose assembly which provides improved insulation efficiency at the higher conditioned air pressures required by military aircraft as well as lower pressure conditions of other Military and Commercial aircraft.
It is a more specific object of the present disclosure to provide a ground support hose assembly which includes an inner stress layer that prevents the inner liner of the hose from expanding as a result of pressurized air in the conduit.
It is a still more specific object of the present disclosure to provide a ground support hose assembly having a woven stress layer composed of high strength cording which prevents the inner liner of the hose assembly from expanding under pressure.
These and other objects, features and advantages of this disclosure will be more clearly understood through a consideration of the following detailed description.
According to an embodiment of the present disclosure, there is provided a ground support hose assembly for providing conditioned air from aircraft ground support equipment to an aircraft. The hose includes an inner liner forming an air conduit, a stress layer surrounding the inner liner for preventing the inner liner from expanding when air is forced through the conduit, and an insulating layer covering the stress layer and the inner liner for insulating air in the conduit.
There is also provided an air hose assembly for coupling a ground support cart to an aircraft. The assembly includes a main section having two ends, each of which includes a connector. The main section includes an inner liner forming an air conduit, a stress layer surrounding the inner liner for preventing the inner liner from expanding as a result of air pressure in the conduit, and an insulating layer surrounding the stress layer and the inner liner for insulating air in the conduit.
The present disclosure will be more fully understood by reference to the following detailed description of one or more preferred embodiments when read in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout the views and in which:
The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the disclosure, its application or use.
Turning now to the drawings,
As shown in
The stress layer 24 is adjacent to and envelops the impermeable liner 22. The stress layer 24 is preferably fabricated as an open weave of a high strength cord or rope material. The weave density is determined by various factors, including the material strength of the cord, the air pressure in assembly 10, and the diameter of inner liner 22. Low pressure applications would use a lighter cord and a more open weave while higher pressure applications would require a thicker cord and a denser weave. The woven cord stress layer 24 adds strength to the hose assembly, while still allowing flexibility when the hose assembly is deflated. Moreover, stress layer 24 prevents inner liner 22 from expanding as a result of air pressure in assembly 10, thus preventing compression of insulating layer 26.
Insulation layer 26 surrounds and envelops the inner impermeable liner 22 and the woven stress layer 24. The thickness of insulation layer 26 is based on the amount of insulation required to minimize temperature increase from surrounding ambient air as cooled conditioned air passes through the ground support hose assembly. The insulation may be either an “open cell” or “closed cell” construction. Open cell insulation, such as open cell foam insulations and fibrous insulations (e.g., polyester batting) is used when it is important to be able to collapse or fold the hose and when moisture absorption in the insulation does not create difficulties. Closed cell insulation, such as closed cell foams, preferably in ½ inch thick polyethylene sheets, is used when moisture is expected that would cause problems for open cell insulations. In either case, the insulating layer 26 may or may not contain a reflective layer.
The outer covering 28 is primarily for protection from abrasion and adverse environmental conditions. The outer layer should be as thin as possible while providing the required protection and flexibility.
The current weaving method for stress layer 24 is a simple process. After the weaving process is completed, the inner liner 22 is pulled through the stress layer, and the insulation layer 26 is wrapped and glued around the, stress layer. After this, the outer shell or outer covering 28 is wrapped around the insulation layer.
The resultant hose assembly 10 of the present disclosure is flexible, collapsible and of high strength. Most conventional aircraft supply hoses of conventional design have evolved from air supply hoses used for civilian aircraft that operate at lower pressures and less severe temperature ranges. Military requirements have introduced new pressure levels, such as those required, for example, by the F-35 fighter jet, thereby requiring new concepts in conditioned air supply hoses. As previously discussed, one such problem among conventional hose designs with higher pressure is that the insulation layer is crushed between the inner liner and the outer shell. Crushing the insulation layer reduces insulation resistance and decreases hose flexibility. As a result, the temperature loss in conventional prior design hoses at high ambient temperatures would require the ground conditioning cart to supply subfreezing air. The subject hose assembly of the present disclosure resolves this issue.
More particularly, as shown in
In practice, a typical non-military commercial aircraft may require conditioned air to be delivered at approximately 1 psig pressure. In contrast, a military fighter aircraft may require approximately 5 psig. Consequently, the internal liner of a conventional ground support hose when used to supply conditioned air to a military aircraft expands with the increased air pressure and crushes its insulation layer against its outer layer (see
The advantage of the hose assembly of the present disclosure over conventional hose assemblies is further illustrated in
Referring now to
The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom. Accordingly, while one or more particular embodiments of the disclosure have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the invention if its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the present disclosure.
