Abstract: In a pump drive circuit, a power source voltage signal supplied to the pump is phase-controlled by a triac connected between the pump and the power source. The period of triggering the triac is determined by a time constant circuit of a UJT, a capacitor and a resistor circuit. The power source voltage signal has its frequency determined by a frequency discrimination circuit. The resistance value of the resistor circuit is selected in accordance with the result of the discrimination. Accordingly, the pump is applied with a voltage signal the phase of which is controlled in accordance with the power source frequency, and is thus driven to maintain a predetermined output.

Abstract: The present device is power system for providing an uninterruptible power supply to an external load comprising a flywheel generator, a first motor, a standby generator, and a transfer controller. The flywheel generator is adapted to supply energy to the external load. The first motor is drivingly connected to the flywheel generator. The first motor is adapted to be connected to a source of power external to the power system. The standby generator is electrically connected to the first motor. A standby motor is drivingly connected to the standby generator. The transfer controller is adapted to switchably interconnect the first motor to the source of power and to interconnect the standby generator to the first motor. The flywheel generator comprises a flywheel having a vertical axis, a shaft connected to the flywheel, and a synchronous A.C. generator arranged about the shaft. The standby motor is a diesel engine having an electric starter.

Abstract: An absolute magnitude circuit is provided wherein an input signal is fed to one input of a differential amplifier circuit, the output of such amplifier circuit being coupled to a second input thereof through a negative feedback loop, such feedback loop having two output terminals with an inverter coupled therebetween; and a switching circuit, responsive to the polarity of the input signal, for coupling a selective one of the pair of output terminals to an output of the absolute magnitude circuit, with the voltage at the output of the absolute value circuit having the same polarity independent of the polarity of the input signal.With such arrangement, since the input circuitry to the operational amplifier is independent of the polarity of the input signal, the gain and biasing of the absolute magnitude circuitry is independent of input signal polarity.

Abstract: A package for enclosing semiconductor elements having side surfaces at which cross sections of conductive wires for receiving a voltage to effect electric plating are exposed. The side surfaces are provided with a static electricity-preventing device, such recesses formed in the side surfaces, insulating films formed on the side surfaces or removable frames positioned on the side surfaces, so that a high voltage due to static electricity from an exterior source is not applied to the conductive wires.

Abstract: A programmable delay circuit comprises input and output multiplexers, a delay device provided between the multiplexers, and a negative feedback path. When the input multiplexer selects an input logic signal, the delay time is controlled by the output multiplexer. When the input multiplexer selects the feedback path, the delay circuit acts as a ring oscillator for generating a square-wave signal whose period is twice the selected delay time. Additional delay devices and multiplexers may be provided between the input and output multiplexers.

Abstract: In the disclosed circuit arrangement for operating the load from alternating current lines, an inductance connected to the load serves as a first energy store. A first control switch switches the energy storage on and off in response to a regulator circuit. A second control switch connected across the inductor and a series current sensor responds to the control circuit to supply current to the load through a diode which prevents current from flowing directly from the power lines.

Abstract: The switch is of the type, known per se, in which an induction coil is driven by an oscillator. The coil is initially positioned in an end cap and secured therein by potting with epoxy resin. This allows the coil and cap to be handled as a unit during manufacture without damage to the coil. The switch is calibrated and adjusted automatically by abrading away part of a resistive layer on a circuit substrate. The circuitry of the switch has its lower potential side coupled to the housing via a capacitor, by means of a conductive adhesive tape trapped between the housing and an end closure.

Abstract: An electronic control circuit for the formation of a monostable switching behavior in a bistable relay, including a logic circuit for the conversion of binary input signals into control signals for a switching circuit through which the direction of current flow is reversible within the relay, whereby the relay is switchable at each status change of the input signal. The electronic control circuit includes at least one time pulse generating circuit with an at least single-step divider circuit, wherein the input signal is applied to an interrogating circuit through which first control signals can be generated immediately after each status change of the input signal and in synchronism with a predetermined timing pulse, and in which the switching circuit consists of a bridge circuit controlled by the first control signals, through which the relay is supplied with short power pulses whose polarity can be reversed by the control signals.

Abstract: Control apparatus for a corona discharge device to be utilized in a xerographic reproduction machine. The control is characterized by utilizing the shield or coronode voltage to derive signals which can be used for maintaining the photoconductive surface of the machine at a predetermined voltage level. The voltage level on the shield or coronode is measured twice, once with the surface in its conducting state and with the surface in its non-conducting state. The difference between the two voltages is compared to a reference voltage to generate an output signal for controlling the voltage applied to either the shield or coronode depending upon which is being used.

Abstract: A solenoid drive circuit for a matrix printer comprises a capacitor (C1) connected in parallel with the series arrangement of a first diode (D2), the solenoid coil (L1), and the collector-emitter path of a transistor (T1). A second diode (D3) is connected in parallel with the coil (L1) and transistor (T1). The capacitor is charged from a d.c. supply which includes a switching regulator (10, T10) via a diode (D1). When the transistor is switched ON by a print signal applied to a terminal (4) the capacitor is discharged resonantly into the coil. The first diode (D2) prevents current flow from the solenoid to the capacitor during the negative half cycle of the resonant frequency so that current in the coil circulates in the loop formed by the coil, the transistor and the second diode. When the transistor is switched OFF the current flowing in the coil is discharged via a further diode (D4) into the storage capacitor (C10) of the d.c. power supply to increase the efficiency of the drive circuit.

Abstract: A printed circuit board connection system provides multiple voltage level interconnection to each individual printed circuit board of a multiple board system via a common circuit board connector mounted on a backplane. Power supply and logic signals at each required voltage level are supplied to electrically isolated regions of the backplane, and are then connected via edge connectors to process control circuits on the respective printed circuit boards. A circuit board extraction handle includes an automatic disabling switch actuator to facilitate circuit board maintenance while power is on.

Abstract: The non-linear alternating current transducer includes a current transformer core (14, 50 or 80) comprising a yoke (14, 50 or 80) for receiving a line conductor (20 or 110) and a secondary winding (22 or 86). The yoke (14, 50 or 80) has an air gap (19, 56 or 101-105) configured to provide a non-linear magnetic circuit response for changes in current through the line conductor (20 or 110). The non-linear magnetic circuit response provides a logarithmic voltage output across the secondary winding (22 or 86). The current transformer (12) is used in a control circuit (10) for sensing, monitoring and interrupting current in the line conductor (20 or 110) such that a trip coil is energized to open the circuit whenever current is sensed above a predetermined current. Also, the logarithmic response provides for high gain at low currents and low gain at high currents to that a very uniform percentage-of-reading accuracy is obtained with a meter operating off of the secondary winding.

Abstract: A DC-to-DC voltage converter is disclosed for converting the voltage from a battery to provide a power supply voltage whose value can be equal to the battery voltage multiplied by or divided by a non-integral factor, e.g. 2/3. The converter operates on the principle of capacitor charge switching, and high conversion efficiency is achieved in operation at very low levels of supply current, such as are utilized in an electronic timepiece.

Abstract: The invention is an improved control for an air conditioner unit in an automobile. The control operates on a time cycle basis instead of using a sensor of air temperatures. The installation is simple, requiring the severing of an electrical lead in the automotive electrical system and making three electrical connections from the invention to the wiring of the automotive electrical system. The invention consists of an adjustable range control, an interval timer, and a relay driver. This combination is connected to the magnetic clutch of the air conditioning unit.

Abstract: A control circuit is disclosed for limiting the polarity and duration of current flowing through an electromagnetic device which is coupled to an alternating current potential source. The control circuit is coupled in series with the electromagnetic device and a switch. The control circuit includes a gate controlled conduction device and circuitry which is utilized to selectively gate that device only during one positive half cycle following the closing of the switch. A second gate controlled conduction device is utilized to discharge a capacitor in timed relationship with the alternating current potential source and prevent recharging of that capacitor until the switch is opened and then closed again.

Abstract: A base drive circuit for power transistors uses a base drive transformer in a dual mode, as a voltage transformer when it is driven to switch on or off, and as a circuit transformer when the transistor is conducting. Particularly a single base drive is used to drive a plurality of base drive transformer, each base drive transformer acting in the dual mode. This isolates the power transistors from each other and avoids differences in switching characteristics of the power transistors from affecting each other.

Abstract: A thermal recording device is equipped with counters and an adder for determining the number of record bits applied to the heat generating unit arrays, and the number of blocks to be simultaneously driven is determined according to this value such that the power source capacity is not exceeded. When over a predetermined value, the blocks may be operated successively without overlap rather than simultaneously.

Abstract: A partitioning circuit will partition into subintervals the time interval between two signals delivered by a recognition circuit, and will activate a gate circuit during one of these intervals which has been predetermined. In addition to the recognition circuit, the sequence of signals from a sensor responding to the occurrence of an at least approximately periodic event, is fed to a comparator circuit which will transmit a pulse to the gate circuit each time a certain signal level has been exceeded. If the gate is active, this pulse will be available for further processing.

Abstract: A keyless vehicle device actuating system for an automotive vehicle combined with an electronic vehicle door unlocking system. Since the vehicle devices, in particular, the engine starting motor can be rotated only when the driver first opens the vehicle doors in accordance with a predetermined code, secondly depresses a plurality of push-button switches arranged within the passenger compartment in accordance with another predetermined code and lastly depresses a starting switch, even if the vehicle doors are opened incorrectly, it is possible to prevent the vehicle which can be started by only depressing a starting switch from being stolen easily. The system according to the present invention comprises a vehicle device actuating signal generating section similar to a door unlocking signal generating section, an ANDing section and a plurality of devices actuated in response to the ANDed signal, in addition to an ordinary electronic door locking system.

Abstract: A portable load bank for loading a generator during a generator test has a set of low resistance coils mounted side by side in a housing and air cooled by a bank of fans. A switching network is provided for testing generators at three discrete load levels. An interlock circuit is provided for safety.