Abstract: Dihydroxy-meta-terphenyl polycarbonates are provided having improved solvent resistance. Alternating and random polycarbonate copolymers resulting from interfacial and single phase organic solvent polymerization techniques with coreactants such as bisphenol A also are provided.
Abstract: The direct (d) and quadrature (q) components of flux, as sensed by flux sensors or determined from voltage and current measurements in a direct field orientation scheme, are processed rapidly and accurately to provide flux amplitude and angular position values for use by the vector rotator of a universal field-oriented (UFO) controller. Flux amplitude (linear or squared) is provided as feedback to tune the UFO controller for operation in direct and indirect field orientation modes and enables smooth transitions from one mode to the other.
Abstract: A radiation imaging device has a plurality of scintillator elements that are each optically coupled to a plurality of internal gain photodetectors. Each photodetector is electrically coupled to a respective detect and hold circuit which amplifies and stores the pulse generated by the photodetector; the stored pulses are sampled via a multiplexed switching arrangement to allow the stored signal from each detect and hold circuit to be processed to produce a digitized imaging signal which corresponds to the energy level of, and location on the array of, the detected incident radiation. The digitized imaging signal is supplied to display memory and analysis equipment for the device.
Type:
Grant
Filed:
August 19, 1991
Date of Patent:
September 1, 1992
Assignee:
General Electric Company
Inventors:
Henri M. Rougeot, Donald E. Castleberry
Abstract: Semiconductor chips are protected from handling damage by formation of a polymer dielectric layer at least 2 microns thick on the chip surface before dicing or shortly after dicing. The polymer dielectric layer may be a thermoplastic material or a thermoset material.
Type:
Grant
Filed:
July 31, 1990
Date of Patent:
September 1, 1992
Assignee:
General Electric Company
Inventors:
Robert J. Wojnarowski, Charles W. Eichelberger
Abstract: Sigma-delta analog-to-digital conversion is used in sensing apparatus that generates a digital signal descriptive of light energy received by a photosensor, such as one of a plurality of photosensors that together receive various elements of a radiant-energy image. A preamplifier generates an analog output signal responsive to the photocurrent of the photosensor, which analog output signal is undesirably accompanied by wideband noise. The analog output signal is supplied to a sigma-delta analog-to-digital converter, the decimation filter of which not only suppresses in the digital signal a component arising from the quantization noise from the sigma-delta modulator portion of the analog-to-digital converter, but also suppresses a component arising from remnant wideband noise from the preamplifier.
Abstract: A phased array sector scanning (PASS) ultrasonic imaging system produces a steered transmit beam with an array of transducer elements that are driven with separate carrier frequencies. A receiver forms the echo signal into a receive beam steered in the same direction as the transmit beam and is dynamically focused. A transmit beam processor Fourier transforms this receive beam to produce a signals corresponding to the separate carrier frequencies which can be delayed to retrospectively dynamically focus the transmit beam or alter the direction in which it is steered.
Abstract: Compositions comprising a polyepoxy compound (preferably bisphenol A diglycidyl ether) and a polyphenylene ether which has been melt processed (e.g., by extrusion) at a temperature in the range of about 230.degree.-390.degree. C., are cured at temperatures in the range of about 190.degree.-250.degree. C. by various epoxy cure catalysts. They may used in the preparation of laminates with excellent dielectric properties, solvent resistance and solder resistance, useful in printed circuit board production.
Abstract: Serial memories are operated so as to reorder samples as they are serially supplied in a pipelined electronics system, such as one for performing matrix multiplications on a chain serial basis. A serial memory comprising (m-1) delay elements and a write multiplexer is operated so as to respond to data samples that occur every m.sup.th one of a series of consecutive sample intervals to generate successive groups of m successive samples, for example. As a further example, a serial memory comprising (mn-1) delay elements and a write multiplexer is operated so as to respond to every m.sup.th one of data samples supplied thereto, which said every m.sup.th data sample is in a first scanning order, to supply those every m.sup.th data samples in a second scanning order. The first scanning order may correspond to scanning in row major order a matrix of samples arranged in m rows and n columns, in which case the second scanning order corresponds to column major scanning order of that matrix of samples.
Abstract: Inclusion compounds of a cyclodextrin, such as .beta.-cyclodextrin, and a palladium halide-diene complex, such as a complex of PdCl.sub.2 and 1,5-cyclooctadiene have been found to be effective hydrosilylation catalysts. One part heat curable organopolysiloxane compositions are also provided.
Abstract: A method for making diphenyl carbonate free of color bodies is provided by reacting an organic hydroxy compound, such as phenol with carbon monoxide and oxygen in the presence of an effective amount of a palladium catalyst, in the form of a palladium material which is used in combination with a quaternary ammonium salt, an inorganic cocatalyst, such as cobalt diacetate and an organic cocatalyst such as benzophenone or 1,10-phenanthroline. Recycling of catalyst values is also provided.
Type:
Grant
Filed:
April 1, 1991
Date of Patent:
August 25, 1992
Assignee:
General Electric Company
Inventors:
Joseph A. King, Jr., Terry E. Krafft, Gary R. Faler
Abstract: Ortho ester-substituted chlorotriazines are prepared by the reaction of a dichlorotriazine with a reactive compound containing an ortho ester group, preferably a 4-(2-methoxy-2-methyl-1,3-dioxolan-4-yl)methyl group. They are useful as capping agents for polyphenylene ethers. The capped polyphenylene ethers form copolymer-containing compositions with polyesters, polyamides and other polymers containing carboxylic acid or amine groups.
Type:
Grant
Filed:
August 15, 1990
Date of Patent:
August 25, 1992
Assignee:
General Electric Company
Inventors:
Farid F. Khouri, John T. Jackman, Otto Phanstiel, IV
Abstract: Ester polyphenols such as the tris(bisphenol A) ester of trimellitic acid are prepared by the reaction of the corresponding aromatic poly(acyl halide) with a dihydroxyaromatic compound such as bisphenol A. They may be employed in the preparation of branched polycarbonates via chloroformate oligomer compositions.
Type:
Grant
Filed:
January 28, 1991
Date of Patent:
August 25, 1992
Assignee:
General Electric Company
Inventors:
Peter D. Phelps, Eugene P. Boden, Paul W. Buckley
Abstract: Polyphenylene ethers are capped by reaction in the melt, with application of vacuum, with at least one trimellitamide, preferably phenyl 4-aminosalicylate trimellitamide. The preferred melt processing method is extrusion with vacuum venting. By this method, the polyphenylene ether is capped with reactive anhydride groups improving its thermo-oxidative stability. The capped polyphenylene ether is capable of forming copolymers with polyamides, and said copolymers are useful as compatibilizers for polyphenylene ether-polyamide blends.
Abstract: A method for the preparation a photo-mask used for photo-imaging selected areas on the surfaces of a three-dimensional printed circuit board substrate. The photo-mask comprises a membrane transparent and degradation resistant to UV light, having at least one side with a contoured shape conforming, and flexible enough to comply with surface irregularities on the surfaces of the three-dimensional substrate being photo-imaged. A pattern of tracks opaque to UV light is posiitoned along the contoured shape of the membrane. The pattern of tracks on the photo-mask is in accordance with a desired conductive metal trace pattern on the surfaces of the three-dimensional printed circuit board substrate. The photo-mask is prepared by photo-imaging and then depositing a track material on a film that conformed to the surfaces of the three-dimensional substrate. An adhesive layer applied over the film cements a membrane material poured upon the adhesive layer.
Type:
Grant
Filed:
September 10, 1990
Date of Patent:
August 25, 1992
Assignee:
General Electric Company
Inventors:
William V. Dumas, Bradley R. Karas, Donald F. Foust, James W. Rose
Abstract: Carbonyl-capped polyphenylene ether is reacted with a cycloalkene, such as cyclooctene using an organometallic catalyst, such as tungsten (VI) chloride/ethyl aluminum dichloride, to produce polyarylene ether/polyoctenamer block copolymers.
Abstract: This invention discloses an optical fiber connect/disconnect for power lasers. The connect/disconnect should allow a laser/fiber user to quickly interface fiber injection input and fiber output couplers while providing an audible and visual optical alignment. The connect/disconnect also offers fiber end protection against dust and mechanical damage.
Abstract: The thermal stability of cyclic polycarbonate oligomers may be increased by reacting the oligomers with an effective amount of organic carboxylic or sulfonic acids.
Abstract: Polyphenylene ethers are capped by reaction in the melt, with application of vacuum, with at least one trimellitamide, preferably phenyl 4-aminosalicylate trimellitamide. The preferred melt processing method is extrusion with vacuum venting. By this method, the polyphenylene ether is capped with reactive anhydride groups improving it therm-oxidative stability. The capped polyphenylene ether is capable of forming copolymers with polyamides and said copolymers are useful as compatibilizers for polyphenylene ether-polyamide blends.
Abstract: A lock detector for a switched reluctance motor (SRM) position estimator monitors the rotor angle estimates from a SRM rotor position estimator to make sure that the estimator is accurately tracking rotor position. Phase flux and current measurements corresponding to the rotor angle estimate of the sampled phase are supplied to dividing circuitry which generates a phase inductance estimate. The phase inductance estimate is compared by logic circuitry to lower and upper inductance limits to determine whether the rotor angle estimate falls within a specified tolerance of a theoretical inductance value. Alternatively, a flux-current map is used to generate a phase flux reference for comparison to the phase flux estimate. A lock detector flip-flop is reset whenever the phase inductance estimate (or phase flux estimate) is outside the specified tolerance, and a signal is sent thereby to disable the SRM.
Abstract: A thermoplastic sheet is placed between a pair of mold members each having a thermal insulator and a mating metal mold insert. RF energy is applied to the inserts to dielectrically heat and melt the thermoplastic sheet. The heated sheet is then deformed in a low pressure press with the insulators. The insulators are then replaced with cool thermally conductive structures to shorten the cooling cycle time. The thermally conductive structures cool the sheet by pressing the sheet in a high pressure press.