Abstract: The starter motor circuit (1) comprises a combination (10) of a starter motor and of a device (LPF) for stepping up the battery voltage. The device for stepping up the battery voltage is intended to prevent a drop in battery voltage caused by a current spike that appears in a power circuit of the starter motor when power is applied thereto. The starter motor in the conventional way comprises an electric motor (DCM) and an electromagnetic contactor (EC). The device for stepping up the battery voltage is a filtering device of the inductive type which is mounted in series with the electric motor in the power circuit and comprises a casing made of magnetic material, a primary winding circuit intended to be inserted in series in the power circuit, and a secondary winding circuit mounted as a short circuit.

Abstract: Provided is an air conditioning system comprised of a plurality of indoor units connected to each other in parallel, each having an expansion valve, and an outdoor unit including a plurality of compressors, in which at least one of the compressors provided to the outdoor unit is a capacity modulation compressor including an electromotive driving unit for driving a plurality of compression units capable of selectively compressing a working fluid, and the electromotive driving unit for the capacity modulation compressor has a stator with a coil wound around thereon and a rotor rotating inside the stator, the rotor being an LSPRM including a rotor core, flux barriers, permanent magnets and conductive bars.

Abstract: A method of controlling in-rush current to a DC motor is disclosed. The method may include operating the DC motor in a first mode including applying back-EMF across a relay coil to maintain the relay in an open configuration when the back-EMF is below a predetermined voltage. The method may also include operating the DC motor in a second mode including applying the back-EMF across the relay coil to maintain the relay in a closed configuration when the back-EMF is equal to or above the predetermined voltage.

Abstract: A circuit to monitor ac line current through resistors employed to provide a ‘step start’ in a power supply, including means to monitor the current flowing through the step start resistors, comprising a peak detector, a sample and hold circuit, an analog to digital convertor and a microprocessor. The output of the current monitoring circuit may be employed to abort starting if abnormalities are sensed. The circuit may also be used to identify when the step start resistors need longer cooling time, and to continuously monitor current at times other than during starting. A timing circuit is also incorporated, which senses zero crossings of the voltage input to the power supply, so as to control the timing of the current monitoring circuit. The discrete circuits employed may be replaced by either a digital signal processor integrated circuit or a general-purpose computer implementing the same steps in a suitable algorithm.

Abstract: Inrush currents in the dc intermediate circuit of a motor controller necessitate the incorporation of protection circuits. These circuits usually take the form of a resistor inserted in series with the intermediate circuit, and the resistor is short-circuited after completion of inrush by a switch positioned in parallel with the resistor. To reduce cable-transmitted electrical noise an earthed noise-decoupling capacitor is added to the intermediate circuit, but it also requires protection against inrush currents. To minimise the number of components, a protection circuit is described which combines noise filtration and inrush protection.

Abstract: A starter circuit for motors, particularly for refrigerator compressors, comprising a starter device which is adapted to be connected to a starter winding and to a steady-state winding of an asynchronous motor, the windings being in turn connected to a power supply line, a capacitor being connected in parallel to the starter device; the starter circuit further comprises a resistive element which is adapted to be connected between the starter device and the capacitor, in order to limit a discharge current of the capacitor on the starter device.

Abstract: A three phase motor starting system is provided to reduce the in-rush current to the motor in order to obtain a soft start of the motor. The soft start of the motor equates to reduced impact forces on motor parts and device components connected to the motor during startup of the motor, especially a startup resulting from a reversal of the direction of rotation of the motor. The system uses an impedance load in series with the motor windings of the motor to reduce the in-rush current to the motor windings, which results in a reduced acceleration of the motor shaft and a soft start to the motor. The impedance loads used by the system can be a resistive load, a capacitive load or an inductive load, depending on the type of impedance load that is desired for the soft start of the motor.

Abstract: A phase shifting network for an inductor motor is provided. The network includes a resistor connected in series with each motor phase coil of a pair of motor phases. The network further includes a capacitor connected between the motor phases. The inventive phase shifting network produces current and voltage waveforms within the motor phase coils that are smoother, more equal, and less subject to harmonic distortion as compared to the waveforms generated by conventional phase shifting networks.

Abstract: In a relay device, a first PTC thermistor has one end connected to a first external connecting terminal, and the other end connected to one end of a second PTC thermistor, the other end of which is connected to a second external connecting terminal, and the thermo-switch is thermally coupled to the first and second PTC thermistors, and connected in parallel with the second PTC thermistor. The thermo-switch is held closed when not heated, and is opened by heat generated by the first or second PTC thermistor. Therefore, the relay device is low in initial resistance, and small in power consumption during heat balance.

Abstract: A starting device for a single phase induction motor, of the type having a cage type rotor and a stator having at least one main coil and one starting coil, which is connected in series with first and second terminals of an alternating current source. The starting device comprises a relay (RL) having at least one contact, with one of the terminals thereof being connected to the first terminal (1) of the alternating current source (F), while the other terminal of said contact is connected to the terminal of the starting coil (L2); and a coil (B) for actuating the relay; an electronic timer circuit (T), which is connected to the terminals of the coil (B) for actuating the relay (RL), in order to open the contact of the latter by supplying a current to the coil (B) thereof, thereby finishing the starting operation of the motor (M), after a period of time has elapsed from the motor (M) powering up.

Abstract: A circuit, safe against an overload, for incrementally varying the power to an electric blower motor used for heating, ventilating and conditioning vehicles, having a PTC resistor in series with other series resistors in the circuit.

Abstract: A reciprocating drive system moves a body of defined inertia, such as a carriage supporting electrostatic spraying means, at full speed between two points at which the direction of movement is reversed. The drive system includes an electric motor with polyphase stator windings and a squirrel cage rotor. Transducers responsive to the arrival of the moving body at the aforementioned points produce output signals controlling a phase switching system which reverses the direction of rotation of the motor. Reversal of the motor torque reverses the direction of movement of the moving body within a given travel and within a given time interval to full speed in the opposite direction. A stator current limiter provides positive coupling in an operative condition and no coupling in an inoperative condition with the motor running at full speed. The motor is selected so that the inertia of its rotor closely matches that of the moving body.

Abstract: A compact resistor device comprises a body of ceramic material of positive temperature coefficient of resistivity having a large number of passages extending through the body between opposite ends of the body, thereby forming very thin webs of the resistor material between adjacent passages. Coatings are formed on the resistor material along the inner walls of the passages to serve as ohmic contacts. The coatings in alternate passages are connected together at one end of the resistor device and the coatings in the other passages are connected together at the opposite end of the device to serve as device terminals. When the device terminals are connected to a power source, current flows through very thin webs of resistor material between ohmic contacts in adjacent body passages. The resistor device is particularly useful in current limiting applications requiring low, room-temperature resistance and in heat-exchanger applications where a fluid to be heated is directed through the passages.

Abstract: A polyphase motor is disclosed in which each coil of the stator winding of, for example, a squirrel cage induction motor is connected in series with a capacitor so that the capacitor, together with the input voltage, causes the stator core to periodically switch from a nonsaturated to a saturated condition and vice-versa so that the flux density is maintained at a uniformly high level. A control winding is provided to generate magnetic flux in the stator to vary the volt-second capacity of the magnetic material of the stator in accordance with varying line, load or other selected conditions. The current in the control winding can be externally controlled or may be provided by a feedback winding wound on the stator.