Abstract: The present invention relates to a control system for an engine driven generator, and more specifically, to a control system for controlling the field current to the field coil of the generator to prevent a rapid decrease in the engine rotational speed throughout a transient period when an electric load, such as a head light or an air conditioner, is switched on and begins to draw current.In one embodiment of the invention, the control system comprises digital control means for repeatedly alternating throughout the transient period between calculating an on period and switching the field current on for the on period, and then calculating an off period and switching the field current off for the off period. The digital control means also detects a high output torque operating condition of the engine, and when such a condition is present, switches the field current on throughout the entire transient period.

Abstract: A resonant forward converter at a switching frequency of 10 MHz provides a small volume point-of-load converter for distributed power systems. The leakage inductance of a transformer is made negligibly small relative to the magnetizing inductance of the transformer. This enables a resonant controllable switch on the primary side of a transformer and a secondary side rectified diode to be switched either on or off at the same time. The capacitance across the primary side switch and the secondary side diode rings with a resonant inductor connected in parallel with the transformer. Both the switch and diode, therefore, have zero voltage switching transitions. Further, the resonant inductor being connected in parallel with the transformer provides a resonant ring that is independent of load.

Abstract: Engine start capability may be added to an aircraft generating system including a variable speed, constant frequency inverter 34 by placing transistors 48 in shunt relation to diodes 22 forming part of a full wave rectifier for rectifying A.C. power from a brushless generator output winding 10 which is normally supplied to the inverter 34 for conversion to constant frequency A.C. power. A source of D.C. power 60 may be connected to the diodes 22 and transistors 48 and the latter are operated by an inverter controller 52 to convert the D.C. power so provided to alternating current to be fed to the brushless generator output windings 10 and cause the brushless generator to operate as an A.C. motor for the starting of a turbine engine 18 or the like.

Abstract: A plurality of permanent magnets mounted at equally spaced angular intervals on a drive shaft are rotated past a plurality of electromagnets at equally spaced fixed angular intervals about the axis of the shaft on a plate supported by a frame. An electric motor drives the drive shaft. The electromagnets are connected across each its own capacitance. At the appropriate speed of rotation the frequency of electrical energy generated by the permanent magnets as they pass the electromagnets causes resonance to occur. This action controls the drive shaft speed. A plurality of capacitors is attached to the base plate and the cross bars of the frame supporting the plate.

Abstract: This invention relates to a mobile emergency medical vehicle having a main transport engine and a medical equipment, supply and patient compartment or module, with such compartment having an independently operated electrical generating means powered by an auxiliary engine capable of providing all of the electrical power requirements of the compartment including exterior and interior electrical lighting, vacuum generating means, power outlet means, compartment air conditioning, heating and the like. The electrical generating means is capable of supplying both 115 volt AC and 12 volt DC power through a converter to the compartment. Switching means is provided to facilitate switching at least a portion of the 12 volt DC power requirements of the patient compartment including exterior and interior lighting and vacuum generating means to the electrical system of the main transport engine upon failure of the compartment electrical generating means or auxiliary engine for any reason.

Abstract: A family of quasi-resonant converters is disclosed as comprising a voltage source, a transformer having primary and secondary windings, and a switch for periodically coupling the voltage source to the primary winding, whereby a charging current appears on the secondary winding. The transformer exhibits a characteristic leakage inductance. A capacitor exhibiting a characteristic capacitance is coupled to the secondary winding to form a resonant circuit including the leakage inductance and the capacitor. The secondary winding is coupled to apply the charging current to the capacitor. A rectifying circuit couples the capacitor to a load, whereby the voltage stored in the capacitor is delivered to the load. The capacitor is directly connected to the secondary winding and to the rectifying circuit to permit positive and negative going voltages to be stored therein, whereby magnetic flux within the core of the transformer is dissipated and the transformer magnetically reset.

Abstract: A powder supply device with a solar cell is made up of a solar cell, a seconary battery, and a voltage control unit. The voltage control unit controls the output voltage of the solar cell, and produces first and second output voltages. The first output voltage is for charging the secondary battery. The second output voltage is for driving a circuit, such as the logic circuit of an electronic calculator.

Abstract: A system is disclosed for recognizing a pattern in a collection of data given a context of one or more other patterns previously identified. Preferably the system is a speech recognition system, the patterns are words and the collection of data is a sequence of acoustic frames. During the processing of each of a plurality of frames, for each word in an active vocabulary, the system updates a likelihood score representing a probability of a match between the word and the frame, combines a language model score based on one or more previously recognized words with that likelihood score, and prunes the word from the active vocabulary if the combined score is below a threshold. A rapid match is made between the frames and each word of an initial vocabulary to determine which words should originally be placed in the active vocabulary.

Abstract: A method for charging a sealed, secondary electrochemical power source having with a water based electrolyte (20), a gas space (20) and the possibility of recombination in accordance with the oxygen cycle during pressure stabilization at a low controlled level. Charging takes place at a constant d.c. voltage whilst the pressure inside the gas space of the power source is reduced by evacuation. An arrangement for implementing the method consists essentially of a vacuum pump which is connected to the gas space of the power source via an evacuation line, and of a constant d.c. voltage source. The vacuum pump is so arranged as to come into operation when the power source is being charged.

Abstract: An improved method and apparatus for the autodiscrimination of barcodes is described. First, an interrupt driven technique for timing the duration of space and bar barcode data is described which allows a microprocessor to decode a first quantum of barcode data during a substantial portion of the time the microprocessor is timing the duration of space and bar data of a second quantum of barcode data. Second, an improved method of locating a barcode margin and eliminating types of barcode to be tried for purposes of decoding is described. Briefly, an integer ratio of space and following bar duration data is compared to a predetermined number, and a determination is made as to whether the space is a margin based on the comparison. Preferably, the two techniques are used in conjunction to speed the autodiscrimination in apparatus for scanning a plurality of different types of bar codes.

Abstract: A method and apparatus for detecting the end of charge of a battery includes the steps of periodically changing, for a predetermined time period, the magnitude of charging current to a battery or bank of batteries, during each such predeterimined period, measuring the voltage drop across the battery or batteries until a predetermined level is reached, and producing an "end of charge signal" in response to the predetermined level of voltage drop being attained.

Abstract: A device for driving an electro-luminescence in which an electrical power source, a coil and a switching means are connected in series to each other. The switching means is time-serially opened and closed by a control unit, and is connected in parallel to the electro-luminescence.

Abstract: An improved battery charger for charging a battery from a dc power source includes a DC-to-DC converter comprising a transformer and a switching transistor connected in series with the primary winding of the transformer. The transformer has its primary winding connected to the dc power source and has its secondary winding connected to the battery to be charged. The switching transistor is controlled to be alternately turned on and off in order to develop across the secondary winding an induce voltage which is rectified to be applied to the battery for charging the same. The secondary winding of the transformer is electrically connected to the dc voltage source in such a manner that the induced voltage of the transformer is in an additive relation with the terminal voltage of the dc voltage source.

Abstract: A voltage regulator for a diesel engine driven alternator includes speed dip control permitting engine recovery, and a voltage signal circuit and a speed signal circuit producing a linear volts per hertz signal for controlling the RMS voltage of the alternator. A speed sensor is connected to the output of the permanent magnet generator. The signal is a filtered square wave with an accurate 50% mark-to-space ratio and converted to a pulse train coincident with the zero crossovers. A ramp circuit followed by a threshold detector and filter produces a linearly increasing voltage with decreasing speed. A level amplifier produces an output at a selected level. A rate amplifier responds to a derivative of the speed signal and clamps the level amplifier off at speed changes below a selected rate. A large and rapid speed change creates an output signal coupled to the reference side of an error amplifier to unload the alternator. The degree and rate of unloading is limited.

Abstract: A power level indicator is described for use with an electric generator for indicating to the operator the percentage of the total power available from the generator which is being consumed by a load.

Abstract: In an inverter for converting a direct voltage into an alternating voltage, having a number of n circuit units connected in series between two outputs, each circuit unit comprising a series connection, having a direct voltage source and a switch with a switching connection, and a unidirectionally conducting circuit element disposed in parallel with the series connection, the inverter having a control unit which operates the switching connections of the switches to render the switches conductive or non-conductive, in order to minimize the circuitry the voltage values of the direct voltage sources have the values U=U.sub.O.2.sup..nu. (.nu.=0, . . . n-1, .sub.O having any desired value), and the control unit is an analog-digital converter (1) having an analog input and digital outputs (A.nu.), whose analog input receives a reference alternating voltage and from whose digital outputs the 2.sup..nu. output is connected to the switch connection (S.nu.

Abstract: A device for determining the charge status of a battery (4) when it is discharged by a load (R.sub.L) and/or when it is charged by a power-supply circuit (1) in which a value representing the nominal charging time and discharging time respectively is stored in first (10) and second adjusting means (11) respectively and is applied to computing means (12). In response to clock pulses applied to the computing means by a clock means (13), the computing means calculate the charge status of the battery by expressing the elapsed discharging or charging time as a fraction of the adjusted discharging time and charging time respectively. The computed charge status is indicated by indicator means (14). During discharging and charging an actual charge status is detected by first (7) and second (16) detection means.

Abstract: A transformerless battery charger having a circuit for connecting the battery to an A.C. power source to supply charging current to the battery including: an inductive impedance in series with the battery for limiting the charging current through the battery. An electronic switch in the form of a TRIAC or SCR is connected in series with the battery, and the electronic switch is normally non-conductive thereby keeping open the charging circuit for the battery. An electronic trigger for turning on said electronic switch is provided to close the charging circuit for the battery as a function of the difference between the instantaneous voltage from said A.C. power source and the battery voltage. The electronic switch and the electronic trigger jointly operating to provide a pulsed charging current to the battery during the A.C. power cycle which is long enough to produce a significant battery-charging effect but short enough to avoid harmful internal heating of the battery.

Abstract: An exponential multiplication power supply is described which is comprised of a plurality of stages each having the ability to store energy and each having a plurality of states, including at least a store state and a stack state. The plurality of stages are arranged in a network such that an input stage in the network is connected to receive a voltage from an external power source and all subsequent stages are connected to at least one other stage for receiving voltage from and through the other stages. A control mechanism is attached to the network stages and operates to place these stages in a repeating sequence of states such that at least one of the stages receives a voltage which is the sum of the voltages stored in at least two other stages. When a stage is receiving voltage or holding voltage it is said to be in the store state, and when a stage is combined with other stages to present an increased voltage, it is said to be placed in the stack state.

Abstract: A battery jumper cable apparatus for safely and correctly coupling a battery to a source of power. The battery jumper cable apparatus includes means for determining the polarity of both the battery and the source of power and thereafter coupling the battery and the source of power, observing proper polarity requirements. The battery jumper cable apparatus only permits the battery and the source of power to be coupled when the battery voltage exceeds a preselected level, the level selected to minimize the possibility of an explosion. A transfer relay is utilized to couple the battery to the source of power.