Abstract: A runtogether sensor comprising a balanced beam having a plurality of tines for insertion between a plurality of parallel wires in motion for sensing a pair of stuck together wires by means of a switch associated with the balanced beam for providing a signal indicative of a runtogether condition to an annunciator which provides verbal announcements of runtogether conditions, as well as other conditions to maintenance personnel for immediate corrective action.

Abstract: An asynchronous bus interface circuit manages the transfer of messages between a host processor memory, and one of two redundant serial data buses by separately processing command words thereby permitting efficient handling of status and data words.

Abstract: A method and apparatus for integral control of a dependent variable in a system having at least two independent variables which influence the dependent variable is disclosed. A difference signal indicative of the difference between the sensed dependent variable and a reference is integrated and provided to a hysteresis transfer function. The output of the transfer function is subtracted from the integrated difference signal and the resulting signal is used to control an independent variable which thereby influences the dependent variable only for small magnitude signal variations in the integrated signal. The integrated signal is used to control another independent variable for large magnitude signal variations in the integrated signal. The other independent variable is typically only capable of influencing the dependent variable for large magnitude signal variations.

Abstract: A metal diaphragm impulse jet pump with no valves is disclosed. The pump may be used in an angular velocity sensor utilizing the Coriolis effect on a fluid jet. A magnetic core is mounted within an anvil and a drive coil is wound around the core. The drive coil may be driven sinusoidally and the diaphragm responds with a vibratory motion in like manner. Sensing poles are provided in quadrature with the drive coils and may be used to sense the vibratory motion and thereby control the fluid flow.

Abstract: A differential torquer having at least one bifilar winding mounted on the torquer is disclosed. The bifilar winding has opposing polarities and the torquer is particularly well suited for use in reducing the temperature sensitivity of torquer servo loops.

Abstract: An improved slave propeller SYNCHROPHASER.RTM. device and mode logic for a multi-propeller aircraft is disclosed. A designated master propeller has at least one associated slave propeller which has its speed and phase controlled with respect to the master by initially controlling the speed of the slave propeller to within a selected constant number of RPM of the master so that the master and slave propellers are periodically in phase and then switching to phase control for controlling the speed of the slave propeller in the presence of a phase difference signal having an absolute magnitude less than a selected absolute magnitude. A selected phase difference relationship between the master and the slave may thus be effected with minimum transient effect on the speed of the slave propeller.

Abstract: An improved slave propeller synchrophaser (10) includes a first control (14) responsive to a phase difference signal (28) and a phase difference reference signal (26) for providing a phase error signal (112) and for providing a propeller speed reference bias signal (40) for a speed governor (46), and also includes, according to the present invention, a second control (12) responsive to the phase error signal (112) for providing an engine power reference bias signal (80) for an engine power control for providing a very limited amount of propeller fine speed control within the dead band of the propeller speed governor while at the same time substantially maintaining engine power at the commanded power level.

Abstract: Circuitry is disclosed for automatically coupling an asynchronous half-duplex bipolar serial data bus to an asynchronous half-duplex unipolar serial data bus by means of extremely simple circuitry.

Abstract: Phase information in a multiple-coil indictive displacement sensor is retained by summing the excitation signal with each of the secondary signals to provide augmented secondary signals which may then be converted to a digital format. A signal processor may then be employed to extract both the magnitude and phase information from the augmented secondary signals by subtracting the magnitude of the primary excitation signal from each of the augmented secondary signals. The resulting signals retain both phase and magnitude information.

Abstract: A high efficiency MOSFET sine wave generator is provided using the class D pulse width modulation principle. A triangle wave at f.sub.0 is compared to a variable amplitude sinusoid at about 1/10 f.sub.0 to provide a pulse width modulated signal for driving a pair of power MOSFETS connected for switching a B+ and a B- power supply. The power switch output is LC filtered and fedback for regulating the amplitude of the modulating sinusoid.

Abstract: The dynamic instabilities in a system which controls prime mover output torque and angular velocity separately are avoided by deriving an accelerating torque signal in an output torque controller where it is added to a sensed torque signal, and the added signal is compared to a commanded torque signal, the difference signal value therebetween serving to control the output torque.

Abstract: A dry lube level sensor for use in a verbal annunciation system for monitoring a wire fabrication process comprises a sealed float tube having a magnetic float for actuating a reed switch within an adapter which connects the float tube to a mounting base for providing a low level signal to the alarm system.

Abstract: A wire tangle sensor is disclosed for sensing tangled wire in a wire fabrication process prior to being fed into a wire drawing machine so that a tangled wire signal may be sent to a verbal annunciator. A verbal announcement of a tangled wire condition is made for immediate corrective action by maintenance personnel to avoid a production shutdown. The wire tangle sensor comprises a metallic probe positioned in close proximity to a moving wire which touches the wire when it becomes tangled thereby grounding the probe and providing a current path for a switch which initiates the verbal announcement.

Abstract: An interface for use between an asynchronous bus and a signal processor is disclosed. The interface utilizes a wraparound receive memory to ensure coherency with very little processor overhead.

Abstract: A differential torquer servo loop having means for comparing the balance between a torquer position related signal and a signal indicative of the difference in the magnitudes of the currents in the differential torquer and for rebalancing any difference therebetween is disclosed. Total current in the torquer is maintained at a constant level to provide a quiet control loop which promotes temperature stabilization.

Abstract: A coherent interface between one or more asynchronous busses and one or more channels in which only one channel is permitted to communicate with a bus at a time is disclosed.

Abstract: A method and apparatus for reducing unnecessary elevator service calls by cycling open and shut a nonresponsive car's door, is disclosed. The doors are cycled in the presence of car demand and indications the car door is shut but the hoistway door is ajar. The doors are cycled only after these conditions persist for a selected period.

Abstract: An interface for use between an asynchronous bus and a signal processor is disclosed. The interface utilizes both a wraparound receive and transmit memory to ensure coherency with very little processor overhead.

Abstract: A plurality of different types of operating systems in buildings organized in geographical groups, each group having a local service office, are monitored at both the local offices and central office for the presence of performance conditions and conditions indicative of an alarm condition.

Abstract: A three-terminal series regulator achieves high efficiency by using an enhancement mode P-channel or N-channel FET for the series regulating element, respectively, for positive or negative voltage regulation thereby eliminating the need for a boost voltage and also minimizing the input-to-output voltage differential at high power levels. Short circuit protection is provided using output voltage and current foldback.