Abstract: A cab signaling apparatus for use on board a railway vehicle which is propelled on rail tracks by an electric drive motor. The invention utilizes a cab signal transmitted to the vehicle through a track circuit in the rails. On board receiving of the cab signal is done by a receiving coil, which may be mounted in front of the lead axle, as a current transformer around the lead axle, or at another location where the cab signal current is relatively strong. The cab signal that is sensed has a cab signal component and an interference component. On board the vehicle a sampled signal is taken which has the characteristic of the electromagnetic interference subjected to the cab signal receiver coil. The sampled signal is then subtracted from the sensed cab signal such that the sampled interference signal cancels the interference component of the cab signal.

Abstract: Highway crossing gate control circuit in which a permanent magnet motor is controlled to drive up and drive down the gate arm by utilization of a single motor control relay and controller contacts which sense the position of the gate arm. The motor polarity is reversed through utilization of the motor control relay, which is operated by a single up input signal. Provision is included for dynamic breaking on the arm moving downward after an initial drive down mode.

Abstract: A cab signaling apparatus for use on board a railway vehicle which is propelled on rail tracks by an electric drive motor. The invention utilizes a cab signal transmitted to the vehicle through a track circuit in the rails. On board receiving of the cab signal is done by a receiving coil, which may be mounted in front of the lead axle, as a current transformer around the lead axle, or at another location where the cab signal current is relatively strong. The cab signal that is sensed has a cab signal component and an interference component. On board the vehicle a sampled signal is taken which has the characteristic of the electromagnetic interference subjected to the cab signal receiver coil. The sampled signal is then subtracted from the sensed cab signal such that the sampled interference signal cancels the interference component of the cab signal.

Abstract: A plurality of power semiconductor switching devices are included in a circuit module in a pattern whereby interconnecting lead lengths are minimized to provide improved circuit characteristics and to insure uniform current sharing when said devices are paralleled during switch-on, switch-off and steady state conditions.

Abstract: An aircraft subsystem provides the aircraft with all its electrical and conditioned air requirements without requiring the extraction of either shaft power and/or pressurized air from the aircraft's main engines. At the core of this subsystem are two rotating assemblies journaled on non-oil lubricated bearings to a housing. One assembly includes a cooling turbine, a starter/generator, a core compressor, and a high pressure stage of a two stage axial turbine, all mounted on a single shaft. A combustor is disposed between the core compressor and the turbine. The other assembly is comprised of the low pressure stage of the axial turbine coupled to a load compressor via a second shaft. The high pressure turbine stage and cooling turbine are sized to drive the core compressor and starter/generator which provides all the aircraft's electrical needs both on the ground and inflight.

Abstract: A signaling apparatus that includes a transmitter having a step-square wave generator for generating a signaling waveform, which waveform is composed of a plurality of square wave signals, and which has an information signal encoded thereupon. The apparatus may also include a signaling waveform receiver, disposed on the railcar, and an information signal decoder, connected to the receiver, for extracting the information signal from the receiver. The stepped-square wave generator produces square waves such that a portion of the duty cycle of one of a plurality of square wave signals overlaps at least a portion of the duty cycle of at least one other of the plurality of square wave signals. A method for signaling in which a multi-stepped square waveform is generated, includes a waveform having a series of superimposed square waves, each of which having preselected amplitudes and duty cycles. An information signal can be encoded upon the multi-stepped carrier waveform such that a coded-carrier signal is created.

Abstract: The invention describes N-fluorosulfonimides which are useful as fluorinating agents. The N-fluorosulfonimides are stable, easily synthesized, and allow the introduction of fluorine into organic compounds under mild conditions.

Abstract: A ring laser gyro has tilting mirrors that can be sinusoidally tilted and therefore cause the optical path defined by the mirrors to be sinusoidally rotated (dithered). The dithering of the mirrors takes place in an angular motion. The mirrors are driven by the same drive signal therefore eliminating the need to precisely control the amplitude and phase.

Abstract: The present invention provides a generally contactless method and apparatus for producing a speed reference for a rail vehicle which amenable to retrofit applications. The invention utilizes a laser source to direct a laser beam on a portion of the wheel and axle assembly of the rail vehicle. In presently preferred embodiments, the laser beam is directed on a tread or flange section of the vehicle wheel. The laser beam is believed to excite the molecules on the surface of the wheel in such a way that magnetic susceptibility is significantly increased. The increased magnetic susceptibility facilitates encoding of a magnetic signal by a magnetic encoding head. This magnetic signal may then be received after further rotation of the wheel by an angularly displaced magnetic receiving head. Processing circuitry is electrically connected to the magnetic encoding head and the magnetic receiving head to derive the speed reference based on the angular velocity and dimensions of the wheel.

Abstract: A coded railway track circuit apparatus is disclosed having the capability of operating during periods of low vehicle activity in a reduced power standby mode. This is accomplished by switching circuitry which interrupts power to most of the components within the track circuit apparatus in response to the recognition by standby initiation circuitry of a preselected standby initiation signal. Power to fail-over indicators which would normally be activated due to a power failure is also interrupted by fail-over interrupt circuitry. During the standby mode, monitor circuitry remains active to recognize occurrence of a preselected wake-up signal. When the wake-up signal is received, full power is restored, thus resuming normal operation. Operation of the fail-over systems is also then re-established.

Abstract: A solid oxide fuel cell stacking assembly is formed of a stack of fuel cell assemblies, manifolds to introduce the reactants to the fuel cell and carry away reaction products and unused reactants, and current collectors at the ends of the stack of assemblies. Each fuel cell assembly is formed of at least two fuel cell subassemblies and an interconnect subassembly disposed between each pair of fuel cell subassemblies. The current collectors at the ends of the stack are preferably in the form of terminal subassemblies. Each subassembly includes a manifold plate, an annular plate-type bellows sealed to a through-plate opening in the manifold plate, and a central element sealed to the inner diameter of the bellows. In the case of the fuel cell assembly, the central element is multilayer fuel cell plate having an electrolyte layer sandwiched between an anode layer and a cathode layer.

Abstract: A system is disclosed to selectively initiate braking at a rear section of a railway train upon initiation of a selected front braking condition at the front section of the railway vehicle. The system utilizes an air sensor preferably constructed in the form of an insect excluder device to detect release of brake pipe air from an exhaust port upon initiation of braking at the front section of the vehicle. An appropriate signal is produced by the air sensor, thus permitting detector circuitry to detect that front braking has been initiated. A transmitter, typically located in the cab of the locomotive, is electrically connected to the detector circuitry. When the detector circuitry indicates that the selected front braking condition has been initiated, the transmitter transmits a brake initiation signal to a receiver located at the rear of the vehicle. The receiver then actuates pneumatic braking equipment at the rear to initiate rear braking.

Abstract: An apparatus and method for supplying cab signal to a rail vehicle on a section of track composed of sequentially adjacent railway track circuit blocks. Respective receivers of each track circuit block are monitored for the presence of a vehicle within that block. The cab signal apparatus is controlled to transmit a signal to a block when the output from the respective receiver in that block indicates a different condition from the adjacent receiver of an adjacent block. Output voltages from adjacent receivers are compared to enable transmission of a cab signal. Comparison of adjacent receiver outputs is accomplished through use of a diode bridge.

Abstract: A master cylinder for use in a brake system having an anti-spin apparatus to provide traction control for the drive wheels of a vehicle. The brake system has a pump responsive to an input from the anti-spin apparatus for directly drawing fluid from a reservoir into the brake system through a separate valve located in a pump compensation port connected to a pressurizing chamber of the master cylinder.

Abstract: A composite includes granules of Type II superconducting material and granules of rare-earth permanent magnets that are distributed in a binder. The composite is a two-phase structure that combines the properties of the superconductor and magnets with the flexibility and toughness of a polymeric material. A bearing made from this composite has the load capacity and stiffness of a permanent magnet bearing with added stability from a Type II superconducting material.

Abstract: A signal generator for generating an electrical signal which varies in accordance with movement of an actuating member includes a plunger slidable mounted within a housing which carries a pair of permanent magnets for generating a magnetic field to be applied to a hall effect generator. As the plunger is moved relative to the hall effect generator, the magnets are also moved relative to the hall effect generator, thereby varying the magnetic field applied thereto. Accordingly, a variable output signal is generated as a function of the position of the input member.

Abstract: A method and circuit for accurately determining the leading edge timing of a pulse of high frequency carrier signal at a receiver which substantially simultaneously receives the same pulse over multiple transmission paths resulting in distortion of the pulse envelope. The amplitude of the pulse envelope is compared with the amplitude of the derivative of the pulse envelope and with a reference threshold amplitude. The leading edge of a pulse is indicated when the amplitude of the pulse envelope exceeds both the amplitude of the derivative and the reference threshold.

Abstract: An arrangement for obtaining flux rate information in a magnetic: circuit including passive means connected across a flux rate sensor for implementing control of said flux rate. The passive means being a tuned magnetic flux rate feedback sensing and control arrangement wherein impedance is tuned and the energy loss characteristic is adjustable. The selection of inductance and capacitance values provides tuning and the selection of resistance affects the energy loss characteristics.

Abstract: Electroless deposition of copper from solution onto a substrate, particularly a polymeric laminate for use in electronic circuitry, is accomplished by first treating said substrate with a stilbene-based fluorescent brightener to sensitize said substrate and thereafter contacting said substrate first with a solution of a catalytic metal and then with an electroless copper plating solution.

Abstract: A vibrating beam force transducer is comprised of an oscillating sensing element having an output frequency indicative of the force applied to the sensing element. The sensing element has a variable electrical resistance which can vary in accordance with temperature fluctuations over the operating range of the transducer.A drive circuit utilizes an AC drive signal source that is electrically coupled to the sensing element to drive the sensing element at its resonant frequency which is a function of the force applied to the sensing element. The drive circuit has a DC compensation circuit that alters the electrical characteristics of the drive circuit in response to variations in the electrical resistance of the sensing element.