Patent Application
20090078828
The inventive subject matter generally relates to anti-ice valve components, and more particularly relates to coupling servo controllers and valve assemblies of the anti-ice valve components.
A gas turbine engine may be used to power various types of vehicles and systems. A particular type of gas turbine engine that may be used to power aircraft is a turbofan gas turbine engine. A turbofan gas turbine engine may include, for example, a fan section, a compressor section, a combustor section, a turbine section, and an exhaust section. The fan section induces air from the surrounding environment into the engine and accelerates a fraction of the air toward the compressor section. The remaining fraction of air is accelerated into and through a bypass plenum, and out the exhaust section. The compressor section, which may include a high pressure compressor and a low pressure compressor, raises the pressure of the air it receives from the fan section to a relatively high level.
A portion of the compressed air then enters the combustor section, where a ring of fuel nozzles injects a steady stream of fuel into a plenum. The injected fuel is ignited to produce high-energy compressed air. The air then flows into and through the turbine section causing turbine blades therein to rotate and generate energy. The air exiting the turbine section is exhausted from the engine via the exhaust section, and the energy remaining in the exhaust air aids the thrust generated by the air flowing through the bypass plenum.
Another portion of the compressed air may be directed from the compressor into a bleed port. The bleed port may be used to bleed the air to other components, such as to an anti-ice valve component, which may operate by using the bleed air. Anti-ice valve components are used to de-ice aircraft surfaces, such as aircraft wings, and typically include at least a valve body and a valve element. A flowpath for the bleed air extends through the valve body, and the valve element is disposed in the flowpath. The valve element may be coupled to a pneumatic servo controller that regulates the pressure of the bleed air through the flowpath. In this regard, the pneumatic servo controller receives a portion of the bleed air from one or more tubes that communicate with the flowpath. Conventionally, the tubes are straight tubes that extend from an opening in the valve body to an opening in a servo housing encasing the pneumatic servo controller. Each opening in the valve body is threaded and includes a bushing disposed therein. A first end of each tube, which is also threaded, is inserted through the bushing and is screwed into the valve body opening to form a leak-tight fit therewith. A second end of each tube is disposed in a corresponding opening of the servo housing and is sealed therein by a sealing ring.
Although the aforementioned anti-ice valve components operate sufficiently in existing engines, they may be improved. In particular, because the bleed air from the compressor may be relatively high in temperature (e.g., greater than 538° C. (approximately 1000° F.)), certain parts of the anti-ice valve component should be capable of withstanding such high temperatures without deleterious effects.
Accordingly, it is desirable to have an anti-ice valve component that may have a relatively long service life, even when repeatedly exposed to high temperatures. In addition, it is desirable for the anti-ice valve component to remain relatively lightweight and to have a similar or smaller footprint than existing anti-ice valve components. Furthermore, other desirable features and characteristics of the inventive subject matter will become apparent from the subsequent detailed description of the inventive subject matter and the appended claims, taken in conjunction with the accompanying drawings and this background of the inventive subject matter.
Anti-ice valve components and methods of coupling a valve assembly to a servo controller are provided.
In an embodiment, by way of example only, the anti-ice valve component includes a servo housing, a valve body, and a transfer tube. The servo housing includes a surface having a cavity formed therein. The valve body is spaced apart from the servo housing and includes a surface having a cavity formed therein. The transfer tube has a first end, a second end, and a length. The first end is disposed in the servo housing cavity, the second end is disposed in the valve body cavity, and the length extends between the first end and the second end and having a portion forming a bend of at least 180 degrees.
In another embodiment, by way of example only, a servo housing, a valve housing, a transfer tube, a first ring-shaped adapter, and a second ring-shaped adapter. The servo housing comprises a first material and includes a surface having a cavity formed therein. The valve housing is spaced apart from the servo housing and comprises a second material that is different than the first material. The valve housing includes a surface having a cavity formed therein. The transfer tube has a first end, a second end, and a length. The first end is disposed in the servo housing cavity, the second end is disposed in the valve body cavity, and the length extends between the first end and the second end and having a portion forming a bend of at least 180 degrees. The first ring-shaped adapter is disposed in the servo housing cavity wherein the first end of the transfer tube is disposed in the first ring-shaped adapter. The second ring-shaped adapter is disposed in the valve body cavity, wherein the second end of the transfer tube is disposed in the second-ring-shaped adapter.
In still another embodiment, a method of coupling a valve assembly to a servo controller includes inserting a first end of a transfer tube into a cavity of a servo housing of the servo controller, the transfer tube including a bend of at least 180 degrees between the first end and a second end. The method also includes attaching the first end of the transfer tube to the servo housing, disposing the second end of the transfer tube into a cavity of a block included as part of the valve assembly, and attaching the second end of the transfer tube to the block.
The inventive subject matter will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and
The following detailed description is merely exemplary in nature and is not intended to limit the inventive subject matter or the application and uses of the inventive subject matter. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.
The valve assembly 102 is configured to receive the high temperature, pressurized bleed air from the compressor (not shown) before it is used for the de-icing process.
The primary valve 110 includes a valve element 148 that seats an inner surface 146 of the valve body 120. The valve element 148 divides the primary flowpath 118 into an upstream portion 150 and a downstream portion 152 and is configured to axially slide through the valve body 120. In an embodiment, the valve element 148 may be coupled, via a shaft 154, that is actuated by a force created by air pressure and a spring 158 acting on a primary piston 156. The primary piston 156 and spring 158 may be disposed in a first chamber 126 formed in the block 122. The first chamber 126 communicates with a first passage 136 that is also formed in the block 122.
The secondary valve 112 may include a valve flange 162 that is configured to slide axially through the valve body 120 and one or more openings 164 through which the shaft 154 extends. The valve flange 162 may restrict passage of bleed air through the valve assembly 102 by sliding over an aperture 160 formed in the valve body 120 that opens or closes the second valve 112. The valve flange 162 is coupled to a support structure 168 having an outer surface 170 that is in slidable contact with a second piston 172, which may actuate in response to air pressure and a spring 174. The support structure 168 also includes an inner surface 176 that defines a second chamber 128 with the valve body 120 and the first piston 156. The second chamber 128 communicates with a second passage 138, which may also communicate with the first passage 136 via an axial channel 178.
A third chamber 130 may be formed in the support structure 168, and may be configured to communicate with a third passage 140 in the block 122. The outer surface 170 of the support structure 168 and the inner surface 146 of the valve body 120 may define a fourth chamber 132, which may communicate with a fourth passage 142 formed in the block 122. A fifth chamber 134 may be defined between the outer surface of the valve body 120 and an inner surface 180 of the valve housing 108 and may communicate with a fifth passage 144 formed in the block 122.
The comparison of bleed air pressures may be performed via a plurality of solenoids, valves, and switches that are disposed along one or more lines 184, 186, 188, 190, 192. The lines 184, 186, 188, 190, 192 may be flexible or inflexible tubular structures, such as pipes, that may be used for air delivery. Referring also to
A second line 186 may receive bleed air from the second passage 138 and may communicate with a direct current (DC) solenoid 210 that is coupled to an overpressure switch 212. The DC solenoid 210 is configured to open or close the second line 186, in response to a pressure differential between the received bleed air and a first predetermined threshold. The DC solenoid 210 also may be electrically coupled to a main controller 182, which may deliver commands from a user to override actions of the DC solenoid 210. The over pressure switch 212 may provide a signal to the main controller 182 indicating that the pressure is higher than a second predetermined threshold. In another embodiment, the second line 186 also directs bleed air to a low pressure switch 214 that is electrically coupled to the main controller 182. The low pressure switch 214 is configured to provide a signal to the main controller 182 if a pressure of the received bleed air is less than a third predetermined threshold. The second line 186 may also feed bleed air to a pneumatic switcher 216.
A third line 190 receives bleed air from the fifth passage 144, a solenoid switcher 220, and a reference pressure regulator 226. This pressure is ported to the third chamber 130 to thereby actuate the primary piston 110.
The fourth line 188 receives pressure from the second passage 138 and the second line 186 through the pneumatic switcher 216. The pneumatic switcher 216 may be set to a fourth predetermined threshold and thus, may open or close to thereby allow the bleed air to flow to the fourth line 188 depending on a differential between the fourth predetermined threshold and the pressure of the received bleed air. The pneumatic switcher 216 switches automatically from primary regulation to secondary regulation in an event that the pressure regulator 226 fails to open or the DC solenoid 210 is actuated.
In an embodiment, the fifth line 192 provides pressure via the fifth passage 144 and may provide air to a balanced pressure valve 220 that is electrically coupled to an alternating current (AC) solenoid 222. The balanced pressure valve 220 is actuated open and closed with an electric signal from the main controller 182. When actuated, the balanced pressure valve 220 opens to allow the bleed air to flow to the fifth line 192. In an embodiment, if the pressure in the fifth line 192 is above a fifth predetermined threshold, bleed air may be exhausted out a relief valve 224. In an embodiment, a reference pressure regulator 226 may be included upstream of the balanced pressure valve 220 to control the pressure of the bleed air in the fourth line 190 to a predetermined value.
It will be appreciated that one or more of the first, second, third, fourth, and fifth predetermined thresholds may or may not be equal to each other. Additionally, one or more of the thresholds may or may not be more or less than another one of the thresholds. Moreover, specific values for each threshold may depend on pressure values at which the bleed air may be suitable applied to the aircraft de-icing system.
As mentioned above, the bleed air flowing between the valve assembly 102 and the servo controller 104 may be relatively high in temperature. Thus, to ensure the bleed air does not leak when traveling therebetween, the transfer tubes 194, 196, 198, 200, 202 may be configured to withstand repeated exposure to the high temperatures (e.g., temperatures greater than 538° C. (approximately 1000° F.)).
In addition to being capable of withstanding high temperatures, the transfer tubes 194, 196, 198, 200 are configured to compensate for distance fluctuation that may occur between the valve housing 108 and the servo housing 250, due to thermal expansion caused by the high temperature bleed air flowing therethrough. In an embodiment, the transfer tubes 194, 196, 198, 200 are relatively thin-walled (e.g., between about 0.25 mm and about 1.3 mm in thickness) having a diameter that may be between about 1 mm and about 25 mm. The transfer tubes 194, 196, 198, 200 may each include a portion forming a bend 222, 224, 226, 228 of at least 180 degrees. In an embodiment, the bend 222, 224, 226, 228 may be about 360 degrees. Each bend 222, 224, 226, 228 may form a portion of a substantially circular, ovular, or elliptical shape that may have a radius that is substantially equal to or greater than 1.5 times a diameter of a corresponding transfer tube 194, 196, 198, 200.
To ensure that the bleed air does not leak out of the valve assembly 102 or the servo controller 104 via the transfer tubes 194, 196, 198, 200, the tubes 194, 196, 198, 200 may be fixedly attached therebetween. In an embodiment, the valve housing 108 may include at least one opening 232, 234, 236, 238 that provides access to the valve body 120, and in particular, the block 122. As depicted in
The servo housing 250 may also include a plurality of cavities 258, 260, 262, 264. The other end of each transfer tube 194, 196, 198, 200 is inserted into corresponding cavities 258, 260, 262, 264. To fix the transfer tubes 194, 196, 198, 200 to the servo housing 250, the tubes 194, 196, 198, 200 may be brazed or otherwise attached to surfaces defining the cavities 258, 260, 262, 264. In another embodiment, adapters 266, 268, 270, 272 (shown in phantom) may be included in the cavities 250, 260, 262, 264. The adapters 266, 268, 270, 272 may be ring-shaped, and the ends of the transfer tubes 194, 196, 198, 200 may be inserted therethrough. The adapters 266, 268, 270, 272 may be made of a material that is substantially similar to that of the transfer tubes 194, 196, 198, 200, and thus, in an embodiment, may be a nickel-chromium alloy, such as Inconel® 718. In still another embodiment, the ends of the transfer tubes 194, 196, 198, 200 may be brazed or otherwise attached to the adapters 266, 268, 270, 272, and the adapters 266, 268, 270, 272 may be brazed or otherwise attached to the servo housing 250.
The transfer tubes 194, 196, 198, 200 may be relatively easily incorporated into anti-ice components. A flow diagram of a method 500 of manufacturing the anti-ice valve component 100 is provided in
In another embodiment, if one or more of the cavities of either the valve body block 122 or the servo housing 250 is sized such that a diameter of a corresponding tube 194, 196, 198, 200 has an optimum capillary joint size for brazing (0.05 mm to 0.2 mm), one or more adapters may be included in the cavities. A flow diagram of a method 600 of manufacturing anti-ice valve components 100 including adapters is provided in
Next, appropriately shaped adapters 266, 268, 270, 272 may be inserted into the servo housing cavities 258, 260, 262, 264, step 608. The adapters 266, 268, 270, 272 may comprise a nickel-chromium alloy similar or a material that is similar to that of the transfer tubes 194, 196, 198, 200. The adapters 266, 268, 270, 272 may be brazed or otherwise attached to the servo housing 250, step 610. Then, opposite ends of the tubes 194, 196, 198, 200 are then inserted into the adapters 266, 268, 270, 272 and brazed or otherwise attached thereto, step 612. To increase the structural integrity of the transfer tubes 194, 196, 198, 200, the anti-ice valve component 100 may be heat treated at an appropriate temperature, step 614. It will be appreciated that a heat treatment temperature may depend on the particular material used for the manufacture of the transfer tubes 194, 196, 198, 200.
In still another embodiment, the transfer tubes 194, 196, 198, 200 may be retrofitted into an existing anti-ice valve component. A flow diagram for a method 700 of retrofitting transfer tubes 194, 196, 198, 200 into an existing anti-ice valve component is depicted in
Anti-ice valve components have now been provided that may operate by flowing bleed air therethrough having temperatures (e.g., at least 538° C. (approximately 1000° F.)). The incorporation of transfer tubes with bends therein allows the servo housing and the valve housing to expand and contract to thereby fluctuate in distance therebetween without causing wear to the component or fatigue in the transfer tubes. Additionally, brazing the ends of the transfer tubes to the valve assembly and to the servo controller may reduce the likelihood of a leak that may occur therebetween. Thus, the valve assembly and servo controller may be made of two different stainless steel formulations, while the transfer tubes may made of a nickel-based alloy. In addition, the anti-ice valve component may remain relatively lightweight and may have a similar or smaller footprint than existing components.
While at least one exemplary embodiment has been presented in the foregoing detailed description of the inventive subject matter, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the inventive subject matter in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the inventive subject matter. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the inventive subject matter as set forth in the appended claims.
