Abstract: An offset hinge flapper valve has a single valve plate rotatably mounted in the flow channel of a cast housing. The valve plate is freely rotatable about a pivot pin welded to the housing. The valve plate has first and second co-planar parts extending on respective sides of its axis of rotation, which is offset from the center axis of the flow channel. These co-planar parts have peripheral edges configured so that the valve plate has the same shape as the shape of the flow channel taken along an oblique section of the cast housing. A brace having an abutment surface is mounted on the valve plate. When the valve plate rotates to a predetermined inclined angle relative to the flow, the brace contacts the housing, thereby blocking further rotation and preventing flutter or instability of the valve plate in the open position.

Abstract: A method and passage system is applicable to hollow structures, such as hollow rib core fan blades, for removing alpha case and contamination, for improving surface texture, and for smoothing diffusion bonded joints to reduce notches and flaws, after fabrication. The passage system allows for venting and full cavity access to permit cleaning of the interior of the hollow structure. The method of cleaning the interior of a hollow structure may comprise applying an etchant to strip the topical layer from the inside of a hollow mechanical structure, such as a hollow core airfoil; or may comprise pumping an abrasive flow through the hollow cavities of the structure.

Abstract: The present invention discloses a system for cooling turbine rotor disk posts in a gas turbine engine with a preferred embodiment illustrating an application for a high pressure turbine stage 1 rotor disk. The disk includes a plurality of circumferentially alternating posts and slots disposed about the periphery of the disk with each slot receiving a dovetail of a radially extending blade. The cooling system comprises a plurality of seal bodies with each seal body including a relatively low volume thermal isolation chamber positioned over the top of a corresponding disk post; a plurality of axially extending blade cooling plenums supplied with cooling air with one of the plenums positioned radially inward of each of the blades; a plurality of shallow, radially extending slots formed in a relatively low stressed axially facing surface of each of the blade dovetails for diverting cooling air from the blade cooling plenums to the thermal isolation chambers.

Abstract: A fan assembly for a gas turbine engine for aircraft has a stator casing made of a first material and an annular abradable seal structure made of a second material comprising an epoxy foam having heat expandable, thermoplastic microballoons filled with a chemical which expands when the second material is cured such that the second material bonds directly to the stator casing upon curing thereby minimizing the number of processing steps during manufacture.

Abstract: A gas turbine engine airfoil includes a serpentine cooling circuit with a branch cooling circuit disposed in parallel therewith for independently controlling discharge of cooling air therefrom through respective discharge holes in pressure and suction sides of the airfoil. Metering orifices are provided between the serpentine circuit and the branch circuit for controlling flow of cooling air into the branch circuit from the serpentine circuit, and therefore controlling discharge of the cooling air from the branch discharge holes relative to the serpentine discharge holes.

Abstract: A fuel valve comprising main fuel valve connected to a burner staging valve such that fuel flow from the main fuel valve is divided between pilot and main domes in a dual annular combustor. The burner staging valve includes a movable spool located within a fixed sleeve such that the spool may be moved both laterally and rotated within predetermined limits. The movable spool and sleeve include pilot, main and inlet windows arranged such that the inlet windows receive fuel from the main fuel valve and the pilot and main windows split the fuel flow between the pilot and main domes of the combustor.

Abstract: A modified inverter/converter unit electronically commutates a switched reluctance machine to provide multiple voltage levels for engine and aircraft applications. A set of power switching transistors apply an exciting current to windings in the switched reluctance machine to produce power at a first voltage level. Additional voltage levels may be provided by using the turns ratio from one or more transformers and the switching frequency from the power switching transistors. Alternatively, additional voltage levels may be provided by using windings of a plurality of transformers internal to the switched reluctance machine.

Abstract: A variable cycle jet engine is provided with a mixing duct assembly which mixes core engine exhaust gas with bypass air when the engine is operating in a turbofan mode and which blocks flow from the core engine and isolates the core engine from the bypass flow when the engine is operating as a ramjet.

Abstract: A multipurpose, automatic, self-contained device for manufacturing or repairing a workpiece made from a composite material includes a frame having an upper frame member and a lower frame member. A mechanical apparatus for providing a compressive force is mounted to the lower frame member and a lower platen is mounted to a movable member of the apparatus. An upper platen, positioned opposite to the lower platen, is mounted to the upper frame member. At least one heater is associated with at least one of the platens to apply heat to the workpiece and at least one temperature sensor is provided for mounting to the workpiece. The lower platen is moved toward and away from the upper platen by the mechanical apparatus to apply a compressive force to the workpiece disposed between the platens as a function of the temperature sensed from the workpiece and/or according to a predetermined schedule or plan.

Abstract: A method of controlling a system is adapted to control flow to throat nozzle and vectoring nozzle actuators. The method comprises the steps of summing a plurality of signals representative of flow to the vectoring nozzle actuators with a signal representative of flow to the throat nozzle actuators to generate a total hydraulic flow signal. The total flow signal is then compared to a signal representative of total pump output to generate a reserve signal. Finally, a scaled rate limit signal is generated from the reserve signal and multiplied by predetermined ratio signals such that the ratio signals are limited by the difference between pump output and pump demand.

Abstract: A mounting means is adapted to hold a large component while it is being bolted to a frame. A hook is attached to the component and adapted to suspend the component in a first position. A bracket is attached to the frame and is adapted to receive the hook, hold the component in the first position, and align the component with a mounting bolt. The component is then drawn to a second, installed, position as the mounting bolt is tightened.

Abstract: A datuming device is provided for use with a machine tool having a movable member which is guided under computer numerical control. The datuming device permits measurement of displacements in a direction not parallel with a displacement probe's line of travel. The device includes a non-sensitive surface which, when probed by the displacement probe, does not indicate a changing displacement when the movable member is moved from a first position to a second position. The nonsensitive surface serves as a reference surface. The device further includes a sensitive surface which, when probed by the displacement probe, exhibits a changing displacement when the movable member is moved from the first position to the second position. The sensitive surface is generally configured as an inclined surface on the datuming device.

Abstract: A generally wedge-shaped vibration damper for rotor blades of a gas turbine engine has a pair of scrubbing surfaces and is loosely retained in a pocket incorporated in the rotor blade platform. The pocket is partly defined by a plurality of surfaces which orient the damper so that it is slidably displaceable and rotatable only in a predetermined plane. During rotation of the rotor disk, the damper of one rotor blade is displaced in a plane transverse to the rotor axis of rotation by centrifugal forces to a position at which one scrubbing surface of the damper abuts a side surface of the platform of the adjacent rotor blade and the other scrubbing surface abuts an inner surface of the platform of the rotor blade in which the damper is inserted. The scrubbing action of the damper serves to damp vibratory motion in the platforms of both blades.

Abstract: An expansion joint for connecting first and second fluid-carrying pipes comprising first and second annular couplings which are operably affixable to respective ones of the pipes. In a preferred embodiment the couplings include cylindrical bores of substantially the same diameter disposed relative to one another to form a passage for providing flow communication between the pipes. An annular bellows extends between the couplings for accommodating relative axial movement and angular misalignment between the pipes and is disposed radially outward of the passage to capture any fluid leaking between the interfacing surfaces of the couplings. A second cylindrical bore of a first one of the couplings engages an outer spherical surface of the second coupling to allow the second coupling to pivot in a manner which accommodates angular misalignment between the pipes.

Abstract: A variable friction force damper utilizes geometric variations in a sliding surface to vary the frictional force. In particular, variation in thickness of the member on which the sliding surface is formed produces a corresponding variation in the displacement of a compression spring. This variation in spring displacement produces a variation in the compression force exerted by the spring, i.e., the force with which the sliding member is pressed against the sliding surface. This in turn causes a variation in the frictional force which the sliding surface exerts on the sliding member. The result is a variable friction force damper having a variable damping capability which allows a controlled response at variable input levels.

Abstract: A manufacturing device is disclosed which has a connector which automatically self-aligns with a mating connector of a docking station. The device includes a receptacle for receiving and holding an unfinished workpiece. At least one connector is provided for coupling the receptacle to at least one process input, such as electrical energy, pneumatics, hydraulics or the like, via the docking station, and an alignment mechanism is provided for automatically aligning the connector for attachment to a mating connector on the docking station when the receptacle is advanced toward the docking station.

Abstract: The invention provides a system and method for automatically, accurately, and repeatable aligning computer numerically controlled (CNC) movable machine components with respect to their respective degrees of freedom of motion. One embodiment of the invention, particularly useful for maintenance purposes, provides a programmable CNC programmer that uses a spindle mounted probe to measure at least two different positions of a point on a movable machine component to evaluate the geometric condition of the component with respect to a degree of freedom of motion of the component and issue alignment instructions to the machine operator. One embodiment provides the invention in a CNC computer program on a programmable media having a programmed set of instructions. The preferred embodiment uses the controller control the CNC machine's operation and spindle movement, perform the machine components' maintenance evaluation, and issue instructions for aligning the components in a consistent manner.

Abstract: The reliability of a fluid multiplexed actuation system is increased by arranging a pair of fluidic multiplexers in a parallel fluid flow path between a selector valve and several fluid actuators. Position sensors associated with the fluidic multiplexers and with the fluid actuators provide feedback signals to a microprocessor. In the event the feedback signals identify a malfunction in the fluidic multiplexer currently supplying fluid to the actuators, the microprocessor will deactivate the malfunctioning fluidic multiplexer and activate a redundant or back-up fluidic multiplexer by actuating the selector valve.

Abstract: An instrumentation light probe holder for use in observing and measuring operating characteristics of rotating blades of a gas turbine engine during engine operation or rotating components of a machine during operation is disclosed. The holder includes an elongated cylindrical member for insertion into an opening or bore formed radially through an annular casing of the gas turbine engine or machine housing. The cylindrical member has a hollow interior for receipt of an instrumentation light probe and a first end for insertion into the casing or housing and for holding an operating end of the probe at a selected set-back distance from the rotating blades or components. A grasping mechanism is provided for releasably holding the light probe in the cylindrical member.

Abstract: A method for inspecting a component of a gas turbine engine or the like having a plurality of similarly shaped structural portions, such as the gear teeth of a gear, the dovetail slots of a turbine disk or the like, includes the steps of: scanning a surface of at least one of the similarly shaped structural portions with an eddy current probe to induce eddy currents in the component; generating a two-dimensional image of the at least one portion from eddy current signals received during scanning, the image including a multiplicity of pixels arranged in a two-dimensional array and each pixel having a gray scale intensity responsive to the eddy current induced in the component at a component location corresponding to a position of the pixel in the matrix array; preprocessing the image to substantially reduce any signals or changes in the gray scale intensity of any pixels relative to the background pixel intensities of the image caused by geometrical characteristics and background noise common to all similarly