Abstract: In an electric power converting apparatus utilized to convert the power of a storage battery into an AC voltage, step up the AC voltage by use of a step up transformer and rectify the secondary voltage of the transformer to directly operate a DC driving motor of a car or an AC motor through an inverter, a rectifier and an inverter are provided to energize the secondary of the transformer from a commercial source and another rectifier is provided on the primary side of the transformer to charge the storage battery.

Abstract: A relay system maintains an emergency door opening device circuit open so that a door of a structure remains closed as long as an electrically energized ventilation system of the structure is supplied with electrical energy from a commercial power source. When the power fails, the relay system closes the emergency door opening device circuit, which includes its own power source, to operate a door opening device which opens a door to the structure to provide emergency ventilation for the structure.

Abstract: A disc record player in which a turntable is driven by a motor comprising a rotor magnet having plural magnetic poles arranged separately along the periphery of the turntable, stator coils disposed in the magnetic field of the rotor magnet and Hall-effect elements sequentially coupled magnetically to the poles of the rotor magnet for generating output signals having polarities corresponding to the polarities of the poles of the rotor magnet, and causing the rotor magnet to rotate by supplying the output signals of the Hall-effect elements to the stator coils, wherein a first and a second speed detecting coils for generating signals having phases different from each other are disposed in the magnetic field of the rotor magnet, wherein the output signals of the first and second speed detecting coils respectively turn the gate circuit off and on and when the turntable is to be stopped, the gate circuit is turned on by the output signal of the second speed detecting coil, and wherein the rotation of the turntable

Abstract: A microprocessor is programmed to generate reference envelopes of a specified time duration and synchronized with clock pulses, and circuit means is associated with such microprocessor for indicating desired speed of a prime mover through comparison of prime mover actual speed with said reference envelope, and means is provided for adjusting prime mover speed to correspond with such reference envelope.

Abstract: This invention concerns a process and a motor unit for driving a load such as an automotive or similar vehicle, which can move at least intermittently by momentum, once it has been set in motion by the motor unit. The motor unit comprises at least two electric motors each driving a propulsion component such as a wheel, an accumulator supplied by a generator which is driven by a combustion engine or similar motor, and means of connecting the accumulator permanently to one of the electric motors and of connecting this accumulator to the other electric motor in order to set the vehicle in motion, this other motor being disconnected from the accumulator once the vehicle is set in motion, and thereafter supplying an electric current which is used to charge the accumulator. The invention can be applied to the driving of any vehicles such as motorcycles, motor-cars and similar vehicles, as well as boats, aircrafts, etc.

Abstract: A control circuit for an electrical device which includes a switch that is electrically isolated from other components. The switch is connected in series with a photovoltaic cell and relay means. The photovoltaic cell is illuminated so that closing of contacts of the switch causes actuation of the relay means. The relay means is connected to actuate the electrical device. Voltage at the switch is limited by the voltage produced by the photovoltaic cell.

Abstract: A pulse generator for the generation of pulses which are synchronously associated with the movement of a mechanical part comprises a toothed element, the teeth of which run past a pick-up head, the pick-up head comprising a first winding fed by a carrier frequency, which produces a field which is modulated by the teeth of the element and a second winding in which a voltage is induced by the modulated field, the induced voltage is supplied to a phase discriminator which produces a pulse sequence having a keying ratio proportional to the relative phase position of the induced voltage and the carrier frequency and the pulse sequence is fed to an integration element which produces a voltage signal proportional to the keying ratio.

Abstract: An electrical actuator such as a direct current solenoid or motor is energized by a square wave voltage having an amplitude which applies full operating voltage to the actuator during each pulse. The duty cycle of the applied voltage is variable between predetermined minimum and maximum values, the minimum value being sufficiently high to overcome the starting hysteresis of the actuator. The control apparatus has particular application to proportional control systems, such as in the selective operation of dual solenoid, hydraulic control valves. A hand controller is provided with a handle having a center off position and on positions in opposite directions corresponding to the two solenoids. As the handle is moved away from the off position in either direction through an initial, relatively small displacement, a switch is actuated to apply the square wave voltage to the appropriate solenoid. Additional movement by the operator causes the duty cycle to vary from minimum to maximum as desired.

Abstract: A black start generating system for a steam plant comprises a gas turbine-generator and a control system which operates the turbine in a modified dead load mode to accept successive load steps in accordance with a black plant startup sequence. In the dead load mode, certain limits are placed on control operations to protect the turbine while permitting load stepping during plant startup.

Abstract: The invention relates to a control circuit for a self-starting electric motor of the type having stator windings in respective series relation with gate type electronic switches which are controlled by control impulses generated in a gate circuit. A motor starting pulse generator is connected to the gate circuit which generates short starting pulses and long blocking pulses. Motor operating controls responsive to commutation impulses are connected to the gate circuit which override the effects of the motor starting pulse generator during normal operation. An integrator for the commutation pulses generates a voltage level signal which corresponds to the speed of the motor. A comparator compares this signal with a reference voltage and, when the signal reaches a predetermined level, the motor starting generator is overriden. When the motor is stopped for any reason the short starting pulses attempt to start the motor at intervals determined by the length of the blocking signals.