Abstract:
An air cycle machine (10) has four wheels mounted on a common shaft (20) for rotation therewith about a longitudinal axis (12) including a second stage turbine rotor (30) mounted to a first end (20a) of the shaft, a fan rotor (40) mounted to a second end (20b) of the shaft, a first stage turbine rotor (50) mounted to a central portion (20c) of the shaft, a compressor rotor (60) mounted to the central portion of the shaft in back to back relation to the first stage turbine rotor, the first and second stage turbine torors being operative to extract energy from a flow of compressed air for driving the shaft (20), and the fan rotor (40) and the compressor rotor (60), in rotation about the axis, and first and second hydrodynamic gas film foil bearings (70, 80) for supporting the shaft for rotation about the longitudinal axis (12).
Abstract:
An aircraft landing locking pin (12) automatically repositions from an engage position, wherein a rotating portion (15) of the landing gear is prevented from rotating, to a released position, wherein the rotating portion if free to rotate, in response to excessive side loading on the landing gear. The locking pin comprises a spring loaded actuator (32, 34, 60) which urges a roller (19) of a lock pin assembly (20) in contact with a bushing (22). In response to a side loading on the landing gear in excess of a predetermined loading, the locking pin is automatically released wherein the roller is expelled from the bushing. The threshold loading is determined as a function of the spring force applied to the lock pin assembly via the actuator linkage. The locking pin automatically reengages when the lock pin assembly is aligned with the bushing.
Abstract:
A divergent flap hinge seal (22) for a thrust vectoring nozzle (10) is pivotally connected to the convergent flap (12), and the divergent flap (14) is pivotally connected to this flap hinge seal (22). An extension (48) on the hinge seal sealingly overlies a recess (50) in the divergent flap (14).
Abstract:
Pixel luminance of an electroluminescent display panel (22) is controlled by a row driver (24) applying a voltage equal to the panel's threshold voltage, and column drivers (26) applying the voltage value above the threshold voltage to bring the pixel (30) to the desired luminance. Each column driver (26) independently samples a stepped ramp voltage signal at its own predetermined time selected as a function of the desired luminance. Each column driver (26) then holds the sampled voltage value, and applies to its corresponding column electrode at the appropriate time a voltage equal to the sampled voltage value. The voltage rate of change of each individual step of the stepped ramped voltage signal can be controlled to vary the luminance levels, and to uniformly separate each of the luminance levels.
Abstract:
Due to the limited structural integrity of the ion exchange membrane, operation at pressure gradients exceeding about 200 psi can cause electrolyzer failure due to the ion exchange membrane being physically forced into the holes of the screen set forming the chamber on the lower pressure side of the ion exchange membrane. Utilizing a porous sheet (14) between the anode electrode (7) and the screen set (1) provides additional structural integrity to the ion exchange membrane and allows simultaneous dual-directional flow of water to the anode electrode while oxygen flows from the anode electrode, thereby allowing high pressure gradient operation.
Abstract:
During operation of an integrated fire and flight control (IFFC) system in a coupled aiming mode, the occurrence of a weapon (172), weapon mount (145) or sensor (146) reaching a constraint limit (210) induces a fade-in of a constraint limiting axis command signal (140) for a respective attitude axis as the aircraft attitude reference, replacing the flight control system attitude feedback error signal (111) for the respective attitude axis. The constraint limiting axis command signals provide the aircraft attitude reference only while the pilot manually depresses and holds an enable switch (920). The pilot command stick input (90) remains the primary input to the IFFC system to thereby provide override capability for pilot command maneuvers.
Abstract:
A fire control system (55) azimuth command and elevation command provides a flight control system attitude reference in response to operation of the flight control system in a coupled aiming mode. The coupled aiming mode is engaged in response to the continuous operation of a pilot switch (920), the azimuth command and elevation command being below respective threshold magnitudes (940, 941), and the operation of the fire control system (55). During operation in the coupled aiming mode, the azimuth command and elevation command replace the yaw attitude feedback error signal and pitch attitude error signal, respectively, as the aircraft attitude reference. During integration of the fire control system and the flight control system, the flight control system is made less sensitive to small pilot command stick inputs below a stick input threshold magnitude, so that small or inadvertent pilot commanded yaw and pitch maneuvers will not affect the yaw and pitch attitude reference commanded by the fire control system azimuth and elevation commands. However, intended pilot commanded yaw and pitch maneuvers (70) maintain full authority at all times.
Abstract:
An optic speed sensor for sensing the speed of a rotating component such as a gear includes a sensor such as an electromagnetic speed sensor disposed in proximity to teeth of the gear. Within the housing of the sensor are one or more electrical signal lines having electrical signals imposed thereon, the electrical signals being indicative of the rotational speed of the gear. Physically connected to the sensor housing is a mating connector. Disposed within the housing of the mating connector are corresponding one or more LEDs, each LED being electrically connected to the electrical speed signals provided by the sensor. Each LED provides an optical signal indicative of the speed of the gear, each LED having fiber optic cable connected thereto which transmits the optical energy output by the associated LED to an optical receiver disposed away from the sensor, such as a control unit for the device incorporating the gear. The optical receiver transforms the optical signal into a form, such as to an electrical signal, more suitable for the type of signal processing performed at the predetermined location.
Abstract:
Methods for bonding metallic structures to thermoplastic and thermoset composite structures are described. The methods include steps for preparing the metallic structure (14) for bonding by knurling a mating surface of the metallic structure and molding a layer of thermoplastic material (50) over the knurled mating surface to produce a bonding surface. To bond a metallic structure (14) to a thermoplastic composite structures (16), the bonding surface of the metallic fitting is consolidated with the thermoplastic composite structure (50). To bond a metallic structure to a thermoset composite structure, a bonding surface is formed on the thermoset composite structure by partially embedding a layer of dry fibre reinforcement in a thermoplastic material layer, coating the exposed dry fiber reinforcement with thermoset resin, and curing the coating dry fiber reinforcement into the thermoset composite structure. The bonding surfaces of the thermoset composite structure and the metallic structure are then fused together by applying heat sufficient to melt the thermoplastic material layers of the bonding surfaces. A resistance heating element (54) is disposed between the bonding surfaces of the thermoset composite structure (16) and the metallic structure to provide the heat required to melt the thermoplastic material layers of the bonding surfaces.
Abstract:
An improved method is described for repairing Co-base superalloy gas turbine engine components by applying a mixture of base alloy powder and base alloy powder with a melting point depressant to the surface of the component and heating at 2250-2300 DEG F to diffuse the melting point depressant isothermally into the base alloy. A protective coating is then applied, during which a heating cycle which ages the base material is used. The resultant component has high temperature creep properties which are significantly better than achieved using the prior art process. The same temperature cycle is also useful in the initial heat treatment of Co-base superalloys, and can also be used for rejuvenation of components which have experienced extensive exposure to engine operating conditions.