Abstract: A magnetic bearing (10) is provided for supporting a rotor (12) for rotation about an axis (14). The magnetic bearing (10) includes a plurality of actuator cores (16) spaced circumferentially about the axis (14), and a plurality of non-magnetic spacers (18A, 18B). Each of the cores (16) has a pair of circumferentially spaced end surfaces (28). Each of the spacers (18A, 18B) is positioned between the end surfaces (28) of adjacent pairs of the cores (16) and has an interference fit with the end surfaces (28) to form a circumferentially preloaded ring (19) of the cores (16) and spacers (18A, 18B) centered on the axis (14). At least one of the non-magnetic spacers is a multi-piece assembly (18A) including a shim (32, 49) having a width selected to provide the circumferential preload within a predetermined range.

Abstract: This invention relates to a piston and a method of manufacturing the same. The piston includes a substantially cylindrical member having a first end and a second end. The cylindrical member includes an open cavity extending axially from the second end to adjacent the first end such that the second end has an inner annular surface defined by an inner diameter. The piston further includes a disk having a radially outer surface defined by an outer diameter fixedly secured to the second end of the cylindrical member. The outer diameter of the disk is substantially equal to the inner diameter of the inner annular surface of the second end of the cylindrical member. A circumferentially extending recessed area for receiving particles produced while fixedly securing the disk to the second end of the cylindrical member is provided on either the radially outer surface of the disk or the inner annular surface of the second end of the cylindrical member.

Abstract: An improved method of manufacturing a piston is provided. The piston includes a substantially cylindrical member having a first end and a second end. The cylindrical member includes an open cavity extending axially from the second end to adjacent the first end such that the second end has an inner annular surface defined by an inner diameter. The piston further includes a disk having a radially outer surface defined by an outer diameter fixedly secured to the second end of the cylindrical member. The outer diameter of the disk is substantially equal to the inner diameter of the inner annular surface of the second end of the cylindrical member. A circumferentially extending recessed area for receiving particles produced while fixedly securing the disk to the second end of the cylindrical member is provided on either the radially outer surface of the disk or the inner annular surface of the second end of the cylindrical member.

Abstract: Plastic deformation and nicking of the conductors (30) of the end turns (20) in the stator (10,12,14) of a dynamoelectric machine during the installation of a temperature sensor (26) is avoided by locating the temperature sensor (26) in a gap (22) between the coils defining adjacent end turns (20), thereby providing a machine capable of rapidly responding to excess heat even in a locked rotor situation before detectable levels of smoke, gas, and odors are generated.

Abstract: Long thermal paths and the resulting slow response times in sealed and electrically insulated thermal sensors may be substantially reduced by insulating and sealing the sensor (26) by a method which includes the steps of providing (30) an electrostatic fluidized bed of electrically insulating resin; locating (34) the sensor (26) at the bed; coating (36) the sensor (26); removing (38) the sensor from proximity to the bed; and curing (40) to the resin to form a uniform, thin coating encapsulating the sensor (26).

Abstract: A method of impregnating electric machinery (32) containing windings with a resin (46) in accordance with the invention includes providing a vessel (30) for containing the electric machinery and an impreganting resin with the vessel having an interior volume (40) in contact with an exterior surface (42) of the electric machinery to be contacted with resin to impregnate the windings; heating the vessel containing the electric machinery to a temperature sufficient to reduce viscosity of the resin upon contact with the machinery to promote flow of resin into contact with the windings; contacting the heated vessel and electric machinery with the resin with the heated electric machinery reducing the viscosity of the resin with the reduced viscosity resin flowing into contact with the windings to be impregnated; curing the resin within the vessel to cause the resin to be retained in contact with the windings and removing the electric machinery from the vessel.

Abstract: A method of fabricating a composite structure having at least one skin molecularly bonded to a core. A skin is provided of reinforcing fibrous material and a thermoplastic matrix. The skin is thermoformed to the general exterior shape of the composite structure. A core having a thermoplastic matrix complementary to the matrix of the skin is molded into the general shape of the composite structure. The skin and the core are placed in juxtaposition in a final forming mold. A thermoplastic material is injected into the final forming mold under isostatic conditions. The thermoplastic material is complementary to the thermoplastic matrices of the skin and the core.

Abstract: A method of fabricating a composite structure having at least one skin molecularly bonded to a core. A skin is provided of reinforcing fibrous material and a thermoplastic matrix. The skin is thermoformed to the general exterior shape of the composite strucutre. The skin is placed in a mold, and a core material is injected into the mold against the skin under isostatic conditions. The core material includes a thermoplastic matrix compatible to the thermoplastic matrix of the skin to form a molecular bond therewith.

Abstract: A composition for a pressure molded core of a composite structure, including a thermal plastic resin. The composition also includes a component to reduce the coefficient of thermal expansion, a lightweight high compressive strength filler, and a blowing agent. The thermoplastic resin may be polyetheretherketone, the component may be carbon fibers, and the filler may be hollow glass microspheres.

Abstract: In order to accommodate post-manufacturing, or secondary operations in precision assemblies using composite materials, where the secondary operations consist of drilling, machining, grinding, lapping, or other material-removing processing, without the need to resort to expensive diamond tooling and while maintaining needed structural integrity, a composite formed of a base material, a matrix, and a machineable material is provided. The matrix is bonded to the base material and the machineable material is rendered integral with the matrix and sufficiently thick to accommodate subsequent material-removing processing to a precision dimension.

Abstract: A polyimide and a process for its preparation wherein the polyimide is prepared from reaction of an organic tetracarboxylic acid or derivative thereof with a mixture of an aromatic diamine and an amine-terminated butadiene-nitrile copolymer. The polyimides of the invention are particularly useful in the preparation of flexible foams.

Abstract: A polyimide and a process for its preparation wherein the polyimide is prepared from reaction of an organic tetracarboxylic acid or derivative thereof with a mixture of an aromatic diamine and an amine-terminated butadiene-nitrile copolymer. The polyimides of the invention are particularly useful in the preparation of flexible foams.

Abstract: A polyimide and a process for its preparation wherein the polyimide is prepared from reaction of an organic tetracarboxylic acid or derivative thereof with a mixture of an aromatic diamine and an amine-terminated silicone. The polyimides of the invention are particularly useful in the preparation of flexible foams.

Abstract: A composite for use in vibration damping and thermal insulation in aerospace applications formed from a core of a foamed polyimide, with a backing layer bonded to one face of the core. This backing layer to include a thin meal foil bonded to the core with a visco-elastic adhesive. Composite provides superior damping and lower weight and significantly improved fire safety compared with existing products.