Abstract:
A multiple piece electrode for use with an electrical discharge machining device (EDM) includes at least one tooth. The electrode also includes a movable, elongated rod positioned inside each tooth. The movable rod may be secured to the tooth by several means such as a clamp mechanism, an epoxy, or by a securing mechanism attached to the processing equipment. When the electrode is advanced longitudinally into the workpiece, the rod forms a deep, small diameter hole and the tooth forms an enlarged opening at one end of the hole. The rod may be rotated to enhance hole depth capabilities. Additionally, the rod may be hollow, thus allowing a dielectric fluid to pass through the rod.
Abstract:
A coolable rotor blade (16) having an airfoil section (18) is disclosed. Various construction details are developed which increase the cooling effectiveness under the airfoil section (18) under a variety of operative conditions. In one detailed embodiment, an array of rows of cooling air holes has two staggered rows in the spanwise direction which are spaced spanwisely in the row and chordwisely from row to row in a predetermined manner to ensure adequate cooling to the leading edge region should the aerodynamic leading edge shift.
Abstract:
A turbine shroud segment includes a center hook (70) along one edge which retains the segment to the turbine structure while permitting thermal distortion of the segment. In a particular embodiment, a segment includes a pair of spaced center hooks (70), a first lateral hook (72), and a second lateral hook (74) disposed oppositely of the first lateral hook. The spaced center hooks retain the segment and prevent radially inward movement of the center region of the segment. The lateral hooks provide supplemental retention while permitting the lateral edges of the segment to move radially outward in response to thermal distortion of the segment.
Abstract:
A pallet (19) of vertically stacked conveyor sections (15-17) utilizes translating cords (23) which may be juxtaposed between translating cords (22) on a workstation (18). The pallet is disposed on a standard lift table (34) so as to vertically align one of the conveyor sections (16) with the similar cords (22) of a workstation (20). Additional cords (51) may be disposed in alignment with the cords (23) of the conveyor sections (15-17) so as to fill the interstices between the juxtaposed cords (50) of the workstation. Grooved drums (28-31, 54) may be used in place of idler pulleys. A live center (66-68) may ensure proper alignment of a cluth gear (73) so as to drive the conveyor section cords on the pallet through a driven gear (71). The cords may be supported by flat shelves (117-119) having teflon3-coated fiberglass surfaces.
Abstract:
An aircraft warning and display system monitors the status of various aircraft equipement (20, 22), and provides cockpit audible and visual messages and indications (52, 53, 59, 67) indicative o f the operational status of the equipment. The operational status of the aircraft is monitored (37, 40), and in response to changes in the operational status of the aircraft for a given equipment status, the priority level of cockpit audible and visual messages and indications are modified to attract the attention of a pilot when pilot action is required. Additionally, information may be displayed (52) to the pilot that indicates specific actions needed to downgrade the priority level of the cockpit messages/indications.
Abstract:
Eutectic reinforcing fibers for high temperature composites include eutectic mixtures such as Al2O3-Y2O3, Cr2O3-SiO2, MgO-Y2O3, CaO-NiO, and CaO-MgO. The fibers may be made by several solidification processes. The edge defined film fed growth process (EFG), however, may be especially appropriate. In this process, a seed having a known composition contacts the surface of a eutectic melt in a crucible and forms a molten film. In the present invention, the composition of the seed may be equal to the composition of the eutectic melt. As the seed is pulled upward, the molten film solidifies to form an eutectic fiber. Directional solidification occurs toward the melt.
Abstract:
A control system for automatically loading and unloading a vehicle (10) from a cargo compartment comprises a plurality of distance measuring sensors (31, 32, 33, 34) attached to specified locations on the exterior surfaces of the vehicle (54, 56, 57) and the cargo compartment (55). The sensors provide distance signals, indicative of the distance between each sensor and the nearest obstruction, to a microprocessor which compares each of the distance signals to reference signals indicative of the minimum allowable clearance between each specified location and an obstruction. During activation of an automatic loading/unloading switch (70), a winch (39) is activated to move the vehicle into or out of a cargo compartment if each of the distances is greater than the corresponding minimum allowable clearance. If any clearance is less than the minimum allowable clearance while the vehicle is being moved, movement of the vehicle is automatically stopped and the height of the vehicle is adjusted (800-815) until all of the distances are greater than the corresponding minimum allowable clearances, after which the winch is reactivated to continue moving the vehicle. The cycle is repeated until the helicopter is in its final position or the automatic loading/unloading switch is released.
Abstract:
A fail safe, segmented drive shaft system includes a segment support assembly (16) comprising a ball bearing (26), for primary rotation, disposed within a journal bearing (28), for secondary rotation, which is disposed within an elastomeric damper (30) that has a vibration probe (34) placed in it for failure detection, and a coupling assembly (18) comprising a flexible diaphragm (66, 67) for primary, flexible coupling between segments and gear teeth (72, 73) which engage for secondary coupling upon failure of the diaphragm (66, 67). The teeth are not concentric with the rotational axis, so vibration indicates failure of the primary flexible coupling.
Abstract:
A pressure tolerant composite panel has an inner fiber reinforced layer, an outer fiber reinforced layer and a core disposed therebetween. In one embodiment of the invention, the inner layer (25) has weakening structures (30) incorporated at the peripheral edges thereof, and has an outer layer (26) of a different and lower modulus of elasticity than the inner layer to provide some degree of elongation. When high internal forces are encountered, the weakening structures allow the inner layer to separate, with the outer layers stretching to absorb the forces without failure. Optionally, strengthening straps (28, 29) are positioned about the panel such that it is compartmentalized into discrete sections to contain damage in localized areas. In an alternative embodiment of the invention, the inner core (27) is produced of a crushable material which has a yield strength sufficient to provide structural support under normal operating conditions. When a high pressure is encountered which exceeds the yield limit, the core is crushed to prevent force transmission to the outer layer. Such a composite panel assures survivability of the panel when subjected to impact damage.