Patents Represented by Attorney John F. Ahern
  • Patent number: 4477227
    Abstract: A turbine rotor structure is disclosed in which shrink-fitted turbine wheels are keyed to the turbine shaft to prevent rotation of the wheels with respect to the shaft in the event of any loosening of the shrink fit. In a preferred arrangement, the rotatable shaft of the turbine is provided with an integral flange, near one end, having two diametrically opposed, notched keyways formed at peripheral locations thereon. Each wheel of the set of wheels used to carry the turbine buckets includes an integral, central hub which extends axially to both sides of the wheel. Further, each hub has pairs of complementary keys and keyways whose members are axially opposite each other at peripheral locations on the wheel hubs. Thus, the key of the first wheel on the shaft mates with the keyway of the integral flange of the shaft and subsequently added wheels mate with each other.
    Type: Grant
    Filed: July 6, 1981
    Date of Patent: October 16, 1984
    Assignee: General Electric Company
    Inventor: Oleg Klufas
  • Patent number: 4473765
    Abstract: A grading layer for a slot armor in an electric machine employs a layer of semi-conducting particles of silicon carbide bonded to the face of insulation of the slot armor. A layer of a tough high temperature paper such as an aramid paper separates the silicon carbide from the windings. The voltage gradient at the radially outerward extremity of the windings is capacitively coupled through the aramid paper to the silicon carbide layer wherein span-wise conduction decreases the peak voltage gradient to reduce the likelihood of the formation of corona and flashover.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: September 25, 1984
    Assignee: General Electric Company
    Inventors: Thomas R. Butman, Jr., Alexander L. Lynn, Kevork A. Torossian
  • Patent number: 4465947
    Abstract: In a dynamoelectric machine, a fan diffuser and collector combination is part of the cooling system of the machine. The fan diffuser and collector is located in the annular chamber defined by the inner and outer end plate shields at one end of the machine. The fan diffuser includes a disk disposed in the radially inner portion of the annular chamber. An inboard surface of the disk is parallel to the adjacent surface of one of the shields. Both surfaces define a diffuser channel which receives substantially all of the gas flow expelled by a fan radially coextensive with the annular chamber. The disk is mounted on the other shield but has an outboard surface spaced away from that latter shield. The disk is foreshortened with respect to a frame wrapper which surrounds the stator and rotor of the dynamoelectric machine thereby forming a collector.
    Type: Grant
    Filed: July 13, 1983
    Date of Patent: August 14, 1984
    Assignee: General Electric Company
    Inventors: Anthony F. Armor, Allan C. Shartrand, David A. Noel, Kathryn M. Rominger
  • Patent number: 4462913
    Abstract: Heavy metal pollutant ions and emulsified fat are removed from a wastewater stream in a two-stage process. The first stage involves the demulsification and removal of fat through the use of chemical emulsion breakers leaving residual fat in suspension and in solution. The second stage involves the preparation and introduction of a calcium sulfide mixture to the wastewater resulting in the precipitation of the heavy metal ions as sulfides and the precipitation of residual fat.
    Type: Grant
    Filed: November 9, 1981
    Date of Patent: July 31, 1984
    Assignee: General Electric Company
    Inventors: Bang M. Kim, Paul A. Amodeo, Jr.
  • Patent number: 4460893
    Abstract: This invention provides a method and apparatus for early detection of wiping contact between a rotating shaft and bearing metal in a flow lubricated bearing. In one form of the invention, a temperature sensor is provided to monitor bearing temperature at a location on the bearing in proximity to the maximum loading position. The sensor signal is sampled periodically by a plurality of sample and hold circuits so that present and immediately past values of the bearing temperature are always on hand. The sampled values are applied to a set of subtracters, each one of which provides a signal representing the difference between two consecutively sampled temperature values. Selected ones of the temperature differences are applied to summers and the largest sum is selected by a high-value selector and compared with a preselected setpoint value representing an excessive temperature change for a given time period.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: July 17, 1984
    Assignee: General Electric Company
    Inventors: Daniel A. Thomas, Paul E. Malone, Gary F. Goth
  • Patent number: 4460659
    Abstract: A copper alloy welding filler for use in arc welding copper to produce sound welds with good mechanical strength and high electrical conductivity is disclosed. The filler consists essentially of a zirconium-boron copper alloy filler metal wherein the concentration ratio of zirconium to boron is at least about 4 to 1; the minimum concentration of boron is about 300 PPM; and the concentration of zirconium is a maximum of about 6000 PPM. The minimum level of about 300 PPM boron on a weight basis eliminates porosity in the weld; while zirconium below about 6000 PPM is effective to eliminate weld cracking without having a detrimental effect on the electrical conductivity.
    Type: Grant
    Filed: June 8, 1983
    Date of Patent: July 17, 1984
    Assignee: General Electric Company
    Inventors: James R. Pedersen, David M. Parker, Robert G. Trechel
  • Patent number: 4453101
    Abstract: An end portion of a free conductor bar of a pole-face winding for the rotor of a large dynamoelectric machine includes a flat at its radially outermost extremity. The end fits loosely within an oversized hole in an amortisseur ring. The presence of the flat displaces the contact line between the end portion and the hole from a thin bridge region of the amortisseur ring to two lines of contact displaced inward into the body of the material of the amortisseur ring. The reduced contact force and the repositioning of the contact location avoids cracking in the amortisseur rings of large dynamoelectric machines.
    Type: Grant
    Filed: September 27, 1983
    Date of Patent: June 5, 1984
    Assignee: General Electric Company
    Inventor: Donald A. Nelson
  • Patent number: 4451786
    Abstract: High noise immunity instrumentation for monitoring brush arcing in a dynamoelectric machine is disclosed. In a preferred form the instrumentation includes a stabilized variable threshold discriminator operative in conjunction with a feedback network and a non-linear high frequency amplifier to provide a discriminator threshold which increases with increasing levels of background noise so that only the arc indicative portions of the signal are passed. A substantial increase in the signal to noise ratio is obtained. The feedback network includes a relatively long time constant integrator and buffer amplifier. Further, to provide an alarm upon the occurrence of brush arcing, an alarm network is provided which includes a comparator for continuously comparing the arc indicative signal with a reference signal which is automatically adjusted to compensate for changes in the average level of the signal from the non-linear high frequency amplifier.
    Type: Grant
    Filed: March 1, 1982
    Date of Patent: May 29, 1984
    Assignee: General Electric Company
    Inventors: Fred H. Sawada, James S. Bishop, Llewellyn A. Blaize
  • Patent number: 4450373
    Abstract: This invention provides apparatus for reinforcing an end of a motor housing of a motor of the type having a minimum vertical dimension. The invention accomplishes this objective in one embodiment by extending two axially extending gussets, which normally terminate short of the ends of the stator housing, until they contact inside surfaces of the ends of the stator housing. A stiffening bar is added along the bottom of the ends of the stator housing between the two extended gussets to carry downward vibration forces from the rotor bearings of the motor through the end shields to mounting rails located adjacent the gussets. This improvement reduces vibration and shifts the natural vibrational resonant frequencies of the structure further away from expected vibrational excitation frequencies of the motor.
    Type: Grant
    Filed: September 12, 1983
    Date of Patent: May 22, 1984
    Assignee: General Electric Company
    Inventors: William H. Miller, Joseph J. Frank
  • Patent number: 4446377
    Abstract: A low collapse speed, self priming, lubricating oil pumping system for a turbomachine, operatively driven by the turbine main shaft, is disclosed. In a preferred form, the invention includes a permanent magnet generator operatively coupled to shaft of the turbine-generator or turbomachine being lubricated and driven thereby to produce an electrical output; an induction motor directly connected to the electrical output of the permanent magnet generator without intervening protective devices such as fuses, switches, and so forth; and a positive displacement pump located in or in proximity to an oil reservoir and driven by the induction motor to pump oil from the reservoir at a flow rate and pressure sufficient to supply oil to the turbine-generator or turbomachine during all operating phases thereof during which lubrication is required.
    Type: Grant
    Filed: May 3, 1982
    Date of Patent: May 1, 1984
    Assignee: General Electric Company
    Inventors: Jens Kure-Jensen, Robert A. Marshall
  • Patent number: 4444064
    Abstract: A method and apparatus for continuously monitoring torque in a rotating shaft. The invention includes a pair of electromagnetic probes in fixed proximity to the shaft and spaced-apart in the direction of the shaft's longitudinal axis. The probes are operable in two modes. In the first, each probe is excited to cause a fixed magnetic pattern to be induced onto the surface of the shaft along a circumferential line adjacent to the probe. In the second mode, movement of the magnetic pattern due to the shaft rotation induces a signal into each probe. Each signal is indicative of the instantaneous angular velocity of the shaft at the corresponding shaft location. The two induced signals are conveyed to phase detection circuitry which produces a signal indicative of the phase relationship between the two input signals. The electrical phase relationship is a direct measure of the twist in the shaft, proportional to torque.
    Type: Grant
    Filed: June 14, 1982
    Date of Patent: April 24, 1984
    Assignee: General Electric Company
    Inventor: John F. Wolfinger
  • Patent number: 4441369
    Abstract: An extended flaw in a material is located in two or three dimensions by propagating ultrasonic energy in a predetermined direction in the material and logging receiving transducer positions and ranges at which individual facets on the surface of the flaw produce maximum amplitude ultrasonic returns. The positions of all of the individual facets in the material are calculated from the predetermined direction, receiving transducer positions and the corresponding ranges. The locations of the individual facets outline the extended flaw.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: April 10, 1984
    Assignee: General Electric Company
    Inventors: Dennis E. Lessard, Paul F. Sabourin
  • Patent number: 4440017
    Abstract: A device for monitoring the leakage of cooling gas for a turbogenerator stator into the stator water-cooling system is disclosed. The device is located next to the generator so that the operative elements are at the generator storage tank operating water level. As cooling accumulates in the storage tank together with cooling water, the gas displaces the water in the leak monitor until the water level rises to a predetermined, adjustable level. When this level is reached, the gas is vented and the water level is restored to equilibrium. Each cycle is recorded on a leak trip counter. When the leakage rate exceeds a predetermined value, an alarm is triggered.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: April 3, 1984
    Assignee: General Electric Company
    Inventors: Sterling C. Barton, Joseph E. Pitoniak
  • Patent number: 4434613
    Abstract: A gas turbine is employed in a combined cycle system to produce one or more chemically useful products. Selected exhaust gases are fed back into the gas turbine compressor so as to establish a stable mixture of working fluid constituents for the gas turbine. The gas turbine is preferably configured in a combined cycle arrangement and both mechanical and thermal energy is extracted from the flow of gases through the load turbine, this energy being used in the production of useful process fluids. The methods and apparatus of the present invention are particularly unique in that here the principal output of the combined cycle plant is not electrical energy but rather valuable chemical products. In short, the gas turbine is being employed as a high-temperature reactor from which both mechanical and thermal energy may be extracted as a result of the energy in the gaseous reaction products.
    Type: Grant
    Filed: September 2, 1981
    Date of Patent: March 6, 1984
    Assignee: General Electric Company
    Inventor: Charles R. Stahl
  • Patent number: 4430575
    Abstract: A turning gear arrangement for a turbomachine such as a large steam driven turbine-generator is disclosed. The turning gear arrangement includes a prime mover system which generates high starting torque for rolling the rotor of the turbine-generator over a narrow low speed range and which provides a lower, substantially constant torque over a wider high speed range. A preferred embodiment of the invention includes a drive gear mounted on the turbine motor shaft; a fixed gearing system through which drive torque is transmitted to the rotor shaft; and a prime mover having an electrical motor to provide high initial torque to start and maintain rotation of the turbine over a low speed range, and a hydraulic turbine providing lower, substantially constant torque to maintain rotation over a higher speed range.
    Type: Grant
    Filed: March 30, 1982
    Date of Patent: February 7, 1984
    Assignee: General Electric Company
    Inventor: Allen B. Quigg
  • Patent number: 4420161
    Abstract: Labyrinth sealing apparatus to prevent rotational instability in the rotor of a steam turbine wherein such instability is of the type induced by steam whirl within the labyrinth seals. In a preferred form, the apparatus includes a plurality of fixed, spaced-apart annular teeth surrounding the shaft of a steam turbine whereby each tooth has a radially inner edge in very close proximity to the rotor surface, and further includes a fixed circumferential row of spaced-apart flow directing vanes encircling the rotor on the upstream side of the annular teeth. Each vane of the row extends radially inward to within very close proximity of a raised annular land on the shaft surface just opposite the vane row. The row of flow directing vanes and the raised land cause substantially the entire quantity of steam which enters the seal to pass through the row of flow directing vanes. Steam flow within the seal is caused to have a retrograde component counter to the direction of shaft rotation.
    Type: Grant
    Filed: May 10, 1982
    Date of Patent: December 13, 1983
    Assignee: General Electric Company
    Inventor: Edward H. Miller
  • Patent number: 4417476
    Abstract: Apparatus for monitoring mechanical vibrations in a component part of an operating machine such as a large electrical power generator includes an electric charge producing transducer, preferably a piezoelectric accelerometer, affixed to the component part of the machine to be monitored, and a charge converter network located within the machine but relatively remote from the transducer. The charge converter network accepts the signal from the transducer, in the form of electrical charge generated at a rate and magnitude representative of the mechanical vibrations, and converts the charge signal to a conventional electronic signal. The charge converter network includes a differential operational amplifier having a resistive-capacitive feedback network providing equal impedance values to a corresponding resistive-capacitive network at the noninverting input of the amplifier. The transducer output is applied between the differential input terminals of the amplifier.
    Type: Grant
    Filed: April 1, 1982
    Date of Patent: November 29, 1983
    Assignee: General Electric Company
    Inventor: William K. Knowlton
  • Patent number: 4414540
    Abstract: For use in combination with a turbine control system, an automatic signal selector to assure selection of a valid signal representation of an operating parameter of the controlled turbine. Redundant sensors provide multiple redundant signals representing the operating parameter. Each signal is applied to a corresponding range detection circuit which generates an alarm signal whenever the sensor signal is higher or lower than preselected values. Simultaneously, each sensor signal and each alarm signal is applied to a selector network which selects one of the sensor signals as a valid signal for turbine control purposes. Thus, if any one of the alarm signals is present, indicating that at least one sensor signal is outside the preselected range, the highest valued sensor signal is automatically selected for control purposes. On the other hand, if no alarm signals are present, the control signal is automatically selected to be an intermediate valued one of the sensor signals.
    Type: Grant
    Filed: July 6, 1981
    Date of Patent: November 8, 1983
    Assignee: General Electric Company
    Inventor: Royston J. Dickenson
  • Patent number: 4408294
    Abstract: A method is disclosed for detecting incipient cracks in the rotor of a turbine-generator while the turbine-generator is on-line operating under normal conditions. Vibration signature analysis is performed on a set of difference signals produced by superposing and subtracting corresponding enhanced background and foreground vibration signals. Each enhanced vibration signal is created by superposing and summing an integral number of vibration signal segments, each segment corresponding to one revolution of the rotor. An incipient crack is manifested principally by the appearance and increase in relative amplitude of signal harmonics at twice the rotational speed of the rotor. The method of the invention is sufficiently sensitive to detect cracks having a depth on the order of less than one-percent the diameter of the rotor.
    Type: Grant
    Filed: March 27, 1981
    Date of Patent: October 4, 1983
    Assignee: General Electric Company
    Inventor: Imdad Imam
  • Patent number: 4403476
    Abstract: A method is disclosed for operating a steam turbine using turbine reserve capacity for attaining operation at elevated loads. In a preferred form of the invention, a bypass overload valve is provided in parallel with the steam admission control valves but is connected to discharge steam to a lower pressure stage of the turbine. During operation of the turbine at less than full load, the bypass overload valve is maintained closed and the control valves are positioned to sustain a preselected load. As load on the turbine increases, the control valves are increasingly opened until they have all reached their fully opened position corresponding to a nominal rated capacity of the turbine. Then, at the discretion of operating personnel, the bypass overload valve is fully opened while simultaneously one or more of the control valves is throttled to offset any steam passing through the bypass overload valve in excess of the amount required to sustain the preselected turbine load.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: September 13, 1983
    Assignee: General Electric Company
    Inventors: Lloyd H. Johnson, Robert S. Couchman, Robert C. Spencer, Jr., John A. Booth, Russell J. Holman