Abstract: A control device for energizing and de-energizing temperature changing devices having a primary control unit and a secondary control unit is provided. The primary control unit includes means for sensing an external temperature and generating a signal (Ps) having a value proportional to the external temperature, means for generating a set point signal (Psp), representing one end of a predetermined primary temperature range, and means for generating a differential signal (Pd), representing the difference between signal Psp and the other end of the predetermined primary temperature range are included. Additionally, the primary unit includes a primary switch for connecting power to at least one temperature changing device which is opened and closed in response to combinations of signals Ps, Psp and Pd.

Abstract: A high temperature titanium-based shaped memory alloy contains from at least 0.1 at. % hafnium. Articles formed from the disclosed alloy have high transformation temperatures. The alloy of the invention can be successfully hot and cold worked to make articles such as springs and wires.

Abstract: An arrangement monitors the values at sensors such as temperature sensors which each generate a voltage value related to the particular sensor temperature. The arrangement produces a digital value representative of the temperature at each sensor, wherein errors caused by fluctuations in the temperature of the arrangement circuitry and aging are reduced toward zero. The arrangement corrects for errors for a wide range of combinations of sensor temperatures and temperature fluctuation in the circuitry of the arrangement. The arrangement includes separate channel circuitry associated with each sensor and temperature independent references associated with each sensor type. Generally, to provide error correction, the arrangement uses stored comparison values to correct for channel-to-channel circuitry differences and stored values associated with the independent references to correct for temperature fluctuation and aging of the arrangement.

Abstract: A flow switch adapted to be attached to a pipe is designed to trip a switch at a preset flow rate. The switch employs a bending metal blade which deflects in the flow stream to move a magnet attached to the downstream side of the blade relative to a reed switch or Hall-effect switch. The switching device is preferably mounted in a slot on a printed circuit board to enable selection of a range of available trip points.

Abstract: A pivotal electrical connector for connecting a shape memory alloy element in the form of a coil spring to a fixed member, the connector including a strip of electrically conductive material having a clip or a pair of legs for securing the connector to one of the coils of the element. A pair of holes may be provided in the strip through which the coil is threaded. A rotational connector is provided in the strip for engaging the fixed member.

Abstract: There is disclosed a data acquisition system for use, for example, in a facility management system, for receiving analog input information, converting the analog input information to multiple-bit digital data, synchronizing the multiple-bit digital data to a serial transfer clock, and restoring the digital data into a bit-parallel format for storage in memory and subsequent digital processing. The data acquisition system includes a plurality of inputs, each input being arranged to receive analog input information. An analog-to-digital converter converts the analog input information at each input to a multiple-bit data word wherein the bits of the data word are in bit-parallel format. A multiplexer couples each of the inputs to the analog-to-digital converter one at a time in succession and a parallel input-serial output register converts the parallel bits to a serial digital bit stream.

Abstract: A surface-acoustic-wave (SAW) H.sub.2 O phase-change sensor capable of distinguishing air, water, dew, frost and ice. The sensor can also distinguish various frost thicknesses. The sensor has a size allowing batch fabrication of the chips, and allowing the device to fit in small spaces such as between fins of an evaporator. The sensor is fabricated on a strong piezoelectric substrate with a short acoustic path length. The SAW phase-change sensor experiences large changes in insertion loss and impedance upon deposition of water in various phases. The sensor has a hydrophobic surface treatment covering the SAW sensor surface, and if placed in a vertical position will self-clean during a refrigeration defrost cycle.

Abstract: A system and method for matching all loaded baggage with passengers during aircraft boarding provides each passenger with a boarding pass and baggage tags, each having the same unique machine readable code imprinted thereon. A scanner and memory device at the boarding point scans and reads a passenger's pass and stores the code. A portable scanner and memory at the baggage loading point scans and reads each luggage tag and stores each code. The stored codes are delivered to the passenger loading gate prior to departure of the aircraft. A computer compares stored passenger codes with stored baggage codes. Lack of a stored loading pass code with a matching stored code of loaded baggage is indicated to permit inspection of such baggage prior to aircraft departure.

Abstract: A microprocessor-based controller with synchronous reset including a processor for processing information having an input receiving an input signal and an output providing an output signal. The input signal conveys information about the process and the output signal controls at least one parameter related to the process. The controller includes a reset circuit for applying a reset signal to a reset terminal of the processor. The reset circuit receives a substantially constant supply signal and is responsive to reception of that supply signal to generate the reset signal, which reset signal has succeeding repetitive first and second signal levels.

Abstract: There is disclosed a new and improved cooling system and method for cooling the air in an enclosed space. The cooling system includes a cooling tower having a plurality of fans arranged to cool a first fluid and a chiller including a condenser thermally coupled to the first fluid, a compressor, and an evaporator. The chiller further includes first conduit means for carrying a refrigerant. A chilled fluid loop including second conduit means circulates a second fluid through the evaporator for cooling the second fluid and is arranged to flow air over the second conduit means and into the enclosed space for cooling the air in the enclosed space. Fan control means controls the speed of the cooling tower fans to minimize the total power consumption of the fan motors and the compressor.

Abstract: There is disclosed an input condition sensing circuit for use in a facility management system which is selectively operable in a first mode for sensing the presence or absence of a voltage potential or a second mode for sensing a high or low impedance and which provides a binary output signal indicative of the condition being sensed and an amplifier coupled to the input for generating a control signal having an amplitude relating to the input condition being sensed. The circuit also includes detecting means coupled to the amplifier for providing a binary output in response to the control signal and indicative of the condition being sensed and select means coupled to the detecting means for selectively conditioning the circuit for operating in either the first or second mode.

Abstract: A differential pressure sensor indicating a housing forming a high pressure chamber, a nozzle mounted on the housing at one end of the chamber, a diaphragm mounted in the chamber to form a low pressure chamber in the nozzle, a spring retainer in the high pressure chamber, a spindle connected to the diaphragm, a tension spring connecting the spindle to the spring retainer, a circular magnet mounted on the spindle and a transducer mounted on the housing to sense the position of the magnet.

Abstract: A top entry top exit wiring duct for routing conductors to terminal devices, the duct including a base, side walls provided along each side of the base forming an open channel, a partial top wall formed by a number of fingers spaced apart to form open ended exit slots for the conductors and having distal ends extending toward the other of the side walls, the distal ends being spaced from the other of the side walls a distance sufficient to define a top entry opening into the duct for the conductors.

Abstract: The compressor controller includes a timing circuit for timing-out a detected fault in a compressor. Upon the fault existing for longer than a predetermined time limit, the controller removes power from the compressor. If the fault is corrected within the predetermined time limit, even momentarily, the timing process is discontinued and the controller continues to monitor the status of the compressor. The controller also includes a delay timer for delaying the re-energizing of the compressor after an interruption or loss of power occurs. The delay prevents short cycling of the compressor. The controller further includes a status display for indicating compressor functions, connections to an alarm which is initiated in the event of compressor failure, a switch for initiating a self test of the controller, and circuitry for a field applied current sensing relay.

Abstract: A signature analysis control system for a stamping press is disclosed which does not require a multiplicity of sensors or reconfiguration upon changing the die. An upper and lower reference signature corresponding to desired force values at particular sampling points during the ram cycle is developed based on a known good sample signature. The force signature for successive cycles of the press is then compared to the upper and lower reference signatures, and the press is inhibited in the event that any sampling point deviates from the corresponding point in the reference signatures.

Abstract: A shape memory actuator for controlling the position of a control member, such as a damper plate in a duct, the actuator including first and second shape memory elements each having an austenite phase transition temperature above which each element assumes a predetermined memory shape and a lower phase which forms when said element is stretched from the predetermined memory shape, the first and second elements being connected to move the control member in different directions when one or the other of the elements are heated to a temperature above its austenite phase transition temperature and an electrical circuit for selectively raising the temperature of one or the other of the elements. The control member may be held in a position between full open and full closed by holding mechanisms which connect the actuator to the control member.