Abstract: A gas turbine engine with dual fuel controls is disclosed. The controls have individual sensors that monitor N2. Each control uses the average value of N2 from both sensors for providing fuel to the engine and performing other operations. The fuel controls contain signal processors capable of determining if their respective sensors are operating out of range, in which case the fuel control uses the value of N2 from sensor associated with the other fuel control. If both sensors are out of range, the signal processors use a stored value for N2 or a value synthesized from another engine parameter. The signal processors are also capable of retesting the sensor over successive cycles to see if the sensor has corrected and is within a tighter range. If the difference between sensor values exceeds a range, the sensor with the best value for N2 is used.

Abstract: A power window system employs a computer based control that receives signals from a window position sensor. As the window moves, the position sensor produces periodic signals as an output. The computer cyclically looks for a change in the frequency of the signals as an indication that the window is obstructed and decelerating. Based on the instantaneous deceleration, the computer recalls a stored value for motor force. The recalled forces are accumulated in synchronism with the position sensor output during the deceleration, manifesting the force applied to the obstruction as the window presses on it. The window is reversed when the accumulated force exceeds a stored value. The uppermost window position is a stored value for the position sensor output obtained when the window is closed for the first time. Each time the window is closed thereafter, an offset is added to that value, the sum defining the point at which the window engages the window seal.

Abstract: The output response of a pilot valve controlled servo 10 is monitored by a computer 20 using a transducer 16 on the main control valve 12 and a transducer 11 on the servo output 10a. The response is compared by determining the predicted output response and response time from a mathematical model for the servo, and if the response or response time is incorrect, a warning indication is provided.

Abstract: An actuator having an optical position sensor is disclosed. The sensor remotely provides via a single optic fiber light having two spectral frequencies of about equal intensities to two inversely acting linear optical attenuators that attenuate light in response to the intensity of a magnetic field varied in relation to the movement of the actuator. The attenuated light from each attenuator is filtered producing two attenuated light signals of the two frequencies that are combined in another single optic fiber and then processed into voltages indicative of their intensities. The position of a moving object attached to the attenuators is derived from the difference of the two signals relative to their combined value, minimizing errors associated with obstructions the optical couplings. The attenuators may be orthagonal strips that slide in unison in slots in an elongated rod containing light transmitters and receivers. Light transmittance of the strips varies along their length.

Abstract: In a gas turbine with stator vanes, actual high speed rotor speed is compared with a value computed from engine pressure to produce an error signal. The error signal is integrated to command stator deflection.

Abstract: In a gas compressor engine, a rotor to which turbine blades (airfoils) are mounted, is constructed of a fiber composite material. In a first zone of the rotor, a first group of fibers are oriented circumferentially, in the direction of rotor rotation. A second set of fibers are oriented off-axis along the entire longitudinal length of the rotor. The first group of fibers overlay the second group only in specific zones, creating zones in which only the off-axis fibers are located. Race-track shaped apertures are cut in these second zones between fibers and these apertures receive the compressor blades that are inserted from the interior of the rotor. The first zones also provide circumferential seals to receive the base of each compressor blade. The first zones are constructed by building up layers of the circumferential fibers in the first zones.

Abstract: In an aircraft gas turbine engine, stator vane deflection and compressor bleed are controlled to alter the compressor airflow vs. compressor pressure relationship map when stall conditions are detected based on compressor speed and compressor temperature, a change that means that less change in pressure required to nudge the compressor from of a stall, accelerating stall recovery. Once the stall has ceased, the stator deflection and bleed are restored to pre-recovery values.

Abstract: A phase modulated signal is split into quadrature components Savg+SaSin(.phi.(t)+kx(t)) and Cavg+CaCos((.phi.(t)+kx(t)). The average value for each signal is compared with the signal to produce a data bit whose meaning is that the average value was exceeded at a sampling instant. The bits at successive times (t.sub.0 and t.sub.1) are separated by an interval set by the Nyquist rate on the peak rate of change of the phase for the signal. Four bits at two sample times t.sub.0 and t.sub.1 are processed to determine the phase quadrants modulo 360 degrees to determine the direction of the phase change. The determination is used to produce a counter enable signal, counter direction control signal (up/down) and optionally an error signal if the phase change during one clock period is more than plus or minus one quadrant. A tracking counter counts the number of quadrants of change from those signals.

Abstract: An actuator having an optical position sensor is disclosed. The sensor remotely provides via a single optic fiber light having two spectral frequencies of about equal intensities to two inversely acting linear optical attenuators. The attenuated light from each attenuator is filtered. The two attenuated light signals of the two frequencies are combined in another single optic fiber and then processed into voltages indicative of their intensities. The position of a moving object attached to the attenuators is derived from the two signals.

Abstract: Fuel flow and nozzle area are controlled by a multi-variable control. A requested fan speed is compared with measured fan speed, producing an error signal which is translated in a proportional-integral inner control loop into a requested compressor pressure signal that represents an acceptable rate of change in compressor pressure for difference between requested and measured fan speed. The error signal is compared with measured compressor pressure; the difference being used in a multi-variable control to adjust fuel flow and turbine exhaust area to achieve the requested compressor pressure.

Abstract: A gas turbine engine has a combustor section using an axial prediffuser with an off-axis cowl passage formed by a diffuser outer wall and a combustor outer cowl. Flow from the prediffuser is split into intermediate outer and inner shroud passages and then the intermediate outer passage is further split into a outer shroud passage and a combustor cowl passage which supplies air to the fuel nozzles. The outer passage and cowl flow split is delayed to improved pressure supply and flow distribution to the outer passage.

Abstract: Power dissipation across the coils in a relay control system is controlled by regulating the voltage across all the coils with a regulator that senses the voltage and varies the conduction time of the switch carrying the total coil current. The regulator includes timing and logic elements that sense if the switch is operating correctly. Another switch is operated by the logic elements to shunt the first switch when the first switch is not operating correctly. This ensures that normal coil function is available in the event of a first switch failure.

Abstract: In an aircraft gas turbine engine having a variable area exhaust, gas turbine compressor operating conditions are sensed to determine a sub-idle condition or a rotating stall. The exhaust area is increased to a maximum when a sub-idle condition is present. If a condition associated with a rotation stall is sensed, fuel flow is decremented but not below a minimum flow. When the rotating stall ends, fuel flow is restored to the normal level and then the engine reaches stabilized operating conditions, the nozzle area is restored at a scheduled rate.

Abstract: Exhaust vectoring control for gas turbine engines having an exhaust nozzle mounted on a ring that is positionally controlled by a plurality of actuators in response to pitch and yaw commands uses signal processing to convert pitch and yaw signals into actuator extensions based upon stored coordinates identifying the location of each actuator connected to the ring in relation to the X, Y and Z reference axes of the engine. The computation of these coordinates takes into account the orientation of the ring. The largest actuator change is selected and limited to a stored maximum allowable change in extension for a fixed or set time interval, such as a signal processor cycle, thereby limiting actuator vector rate. The limited change is divided by the largest computed extension change, producing a ratio or factor that is multiplied by the computed changes for the other actuators, producing a set of actuator signals that are simultaneously applied to their respective actuators for the processor cycle.

Abstract: The voltage across a temperature responsive diode supplied with constant current is sensed and applied to two analog amplifiers with different gains. The output from each amplifier is applied to a sample and hold circuit. The output from each sample and hold circuit is applied to an analog to digital converter to produce two binary signals. The minimum binary value of one signal corresponds to the minimum voltage drop; the maximum to the drop at an intermediate temperature. The minimum binary value of a second signal corresponds to the drop at the intermediate temperature and the maximum binary value of this signal corresponds to the drop at a maximum temperature. Both binary signals are applied to the multiplexer which selects one signal to address a stored temperature in a look-up table.

Abstract: Elevator load is computed from sensors. These sensors provide load signals. The load, defined by a stored load equation, is the product of those signals and a gain signal summed with an offset signal. Load computation using those signals is augmented by a recalibration routine. The routine to adjust the offset is initiated when the car transits floors in an empty car condition. Current equation offset and the latest empty car signal levels are compared. If the difference is less than a value the last levels become the offset; if not the equation offset is incremented changed. Load computation is further augmented by sensing car rollback, to augment the gain signal. Rollback may occur after the brake holding the car in position is lifted but before a speed dictation signal is given to the motor, causing the car to move if motor torque is not matched to the load as computed from the load equation.

Abstract: An operational controller is located in the elevator car, and a mobile transceiver, also located in the car, is connected to the operational controller, which includes a microprocessor that controls the transceiver. A stationary transceiver is located in the lobby, and the two transceivers are connected over two pairs of wires in the traveling cable. These transceivers communicate by dual tone combinations, each combination identifying a hall button, a hall lantern, and a position indicator in the lobby.

Abstract: A transmitter has a plurality of parallel inputs, and each input is connected to a switch. The transmitter receives a trigger signal that has a constant frequency. Using the trigger signal, the transmitter provides a signal which consists of individual series signals, each one of the series signals representing the status of one of the switches. The series signal also includes a sync signal which precedes the series signals associated with the status of the switches. These series signals are generated in synchronism with the trigger signal that is applied to the transmitter. A receiver receives the series signals and also the trigger signal. The sync signal is detected in the receiver, and a status signal is generated in response to each of the series signals following the sync signal as those signals are received. Each status signal is applied to an input which is identified by the number of repetitions made by the trigger signal after the sync signal is detected.

Abstract: A computer-controlled system, such as an elevator, is tested by augmenting computer operation with a diagnostic device containing a computer and coded diagnostic programs that a service technician identifies through a keyboard using diagnostic test codes that appear on an overlay which contains special codes and identifiers associated with numerical displays and lights on the diagnostic device for correlating test results to the test performed according to the program.

Abstract: A flywheel or disc rotates around a circular stationary surface, for example, a shaft, the disc is configured relative to the stationary surface so as to define the tapered area or gap at diametrically opposite positions. Two flyweights that are mounted on the disc and mechanically interconnected pivot on the disc radially outward as the disc speed increases. A pair of rollers are located in the space between the disc and the stationary surface, and, as the weights move radially outward, are progressively forced into the tapered area or gap, eventually contacting the stationary surface where they are wedged in the gap, abruptly stopping the rotation of the disc. The counterweights' center of masses and the pivot points are such that the centrifugal force of one weight is slightly greater than the other. An overspeed switch is operated by the weights at a certain speed.