Abstract: In an apparatus for driving and controlling a power window according to the present invention, a blanking period is provided to stop the comparison between a variation amount of motor current and a threshold value, during a predetermined period of time T after the drive of the motor has been started. The catching of a foreign object is detected based on the motor current value in the latter half Tm of the blanking period, and is detected based on the variation amount of the motor current after the blanking period. Erroneous operation due to noise at the beginning of the drive of the motor is prevented, and the catching of a foreign object is reliably detected.

Abstract: A method for determining at least one operating parameter to determine the operating condition of a polyphase electric motor system comprises sensing the instantaneous current signal and the instantaneous voltage signal as a function of time for more than one electrical phase of the motor. The sensed current signals and the sensed voltage signals are both amplitude demodulated and phase demodulated to provide amplitude demodulated current and voltage signals as a function of time and phase demodulated current and voltage signals as a function of time. The resulting amplitude and phase demodulated signals are used to determine one or more of the following electrical parameters as a function of time: total real power, real power per phase, total reactive power, reactive power per phase, total apparent power, apparent power per phase, overall power factor, power factor per phase, electrical impedance per phase, and electrical balance.

Abstract: A system and method for controlling a wiper for a vehicle window on a lift gate. The control system and method include an ignition switch (12), lift gate position switch (14), window position switch (16), washer switch (18) and wiper switch (20) for generating (42) multiple input signals. The control system and method also include a microprocessor (24) for processing (44) the input signals to determine wiper operations, and an output driver (26) for generating (46) an output signal to control the wiper in response to the wiper operations determined.

Abstract: A circuit arrangement for driving an inductive load (M) having a first (1) and a second sub-winding (2), which sub-windings can be connected to an energy source (5) via switch devices (9, 10) periodically driven by a controller (16). The source produces a DC voltage (U5) to supply energy to the load (M). Alternatively, the sub-windings are coupled electrically (3) and magnetically (6) like an autotransformer, while voltages (for example U8) for feeding the controller (16) can be tapped from the transformer end terminals (7,8) which are formed by non-interconnected terminals of the sub-windings (1,2). In this circuit arrangement start and operation is ensured with the least possible additional circuitry even if the DC voltage taken from the energy source is less than the supply voltage necessary for the controller.

Abstract: Circuitry for selectably connecting the body node of drive transistors of a motor control circuit. In particular, those transistors that are turned off when operating the motor in a unipolar mode have their body nodes switched so as to be connected to a reference voltage, such as ground, during unipolar mode, and to be connected to the transistor source during bipolar mode (i.e., when the transistors are active). The circuitry also is operable to briefly connect the body nodes of the transistors to their source when the opposing drive transistor is commutated, in the unipolar mode. In this way, forward biasing of inherent diodes in the drive transistor is avoided in unipolar mode, except when useful to clamp the inductive kick of the motor coils.

Abstract: A unit for controlling the operation of the electric motor is provided together with a control device, electrically connected to the body of the operator, to act on the control unit via a relay means in such a manner as to halt and reverse the rotation of the electric motor following conductive contact between the operator's body and the metal component. For receiving and supporting the feet of the operator, two conductive plates insulated from the ground are provided in such a position that the operator rests his feet via conductive shoes on them when working with the machine. The plates are connected to the control device, and the metal component is electrically connected to earth. The support plates are electrodes for the passage of low voltage electric current from one plate to the other via the body of the operator. The control device stops the motor following conductive contact between the operator's hands and the metal component.

Abstract: A drive control circuit includes a first and a second relays, each of which selectively connects one of the terminals of a motor with a power supply. A power connecting circuit can connect the power supply with each one of the relays. A control circuit controls the power connecting circuit to disconnect the power supply from the first and second relays, and then controls to switch the connecting arrangements between the power supply and each terminal of the motor utilizing the first and second relays. Therefore, the rotational direction of the motor is switched, or the rotation of the motor is stopped.

Abstract: A circuit for controlling a current in a load, the circuit includes: structure for connecting the circuit to a source of power, the power source connecting structure including a power switch having off and on operating modes; structure for connecting the circuit to a supply of a pulse width modulated (PWM) control signal, the PWM supply connecting structure including an AND gate having first and second input structure and an output structure, one of the first and second input structures connected for receiving the PWM control signal, and the AND gate output structure connected to the power switch for operating the switch; structure for monitoring the current in the load, the monitoring structure including a differential amplifier, the differential amplifier having an instantaneous output voltage signal proportional to the load current when the power switch is in the on operating mode, structure for comparing a value derived from the instantaneous signal to a high reference voltage signal and a low reference v

Abstract: A tone synthesis system employs a filtered delay loop which is excited by an excitation signal. The excitation signal corresponds to the impulse response of a body filter to the system which is to be simulated. High quality tone synthesis can be achieved without the necessity of providing a complicated body filter.

Abstract: Method and system for controlling the operation of a motorized wheelchair where the motors have discrete predetermined speeds thus requiring little user intervention to operate and the motors may be controlled to act as generators to provide dynamic braking of the wheelchair.

Abstract: A switched reluctance electronic motor includes a rotor mounted for rotation about an axis and including a plurality of rotor poles. A stator surrounds the rotor and includes at least three stator phases. The motor also includes a circuit for controlling the motor, the circuit includes a pulse generator for supplying a seek current to each of the phases of the motor without causing rotation of the rotor. The seek currents in the phases each have a respective seek current rise time. The rise time is a function of the proximity of the rotor poles to the respective phases.

Abstract: A frequency signal control circuit for a vibration type motor apparatus, which uses as a driving force a vibration generated by application of a frequency signal to an electro-mechanical energy conversion element thereof, inhibits a shift operation of the frequency signal to a lower frequency when a detector detects that a voltage level of a power supply is less than or equal to a predetermined first level, and shifts the frequency to a higher frequency when the detector detects that the voltage level is less than or equal to a second level, the second level being lower than the first level.

Abstract: A pulse width modulation controller particularly useful for a variable speed variable torque electric motor. Inputs to the controller are a desired RPM signal, a motor electrical signal which is a function of the RPM of the rotor of the motor and its angular position relative to the stator, and a torque feed back signal derived from the power phase winding circuits of the motor. The controller produces pulse width modulated power drive signals which are applied to power switches of the power phase winding circuits of the motor to allow electric current to flow through the power phase winding circuits when power phase enable signals produced by the controller sequentially enable the power switch of a power phase winding circuit to do so. The duty cycle of the power drive signals is a function of the difference between the desired and actual RPM of the motor and the torque of the motor.

Abstract: A three-phase electronic inverter for an electric induction motor can operate the latter silently without the generation of magnetorestriction noise where the voltage of the rectifier outputted to the power transistor bridge is controlled by a TRIAC with regulation of the angle of conduction while the power transistor are pulsed in response to the output of a microprocessor through level adapters constituted by operational amplifiers.

Abstract: A rotary-compressor control system for electric refrigerators using rotary compressors for cooling the inside of the refrigerators, in which a battery for feeding direct-current power, an inverter power section for converting direct-current (d-c) power from the battery into a low-voltage three-phase alternating-current (a-c) voltage, a low-voltage three-phase induction motor for driving the rotary compressor with the low-voltage three-phase a-c power obtained in the inverter power section, and a control circuit for controlling the inverter power section on the basis of a control command signal given from the outside, so that the rotary compressor is driven by the three-phase induction motor that operates with a low voltage of the order of battery voltage.

Abstract: An electronic musical instrument has a waveform memory and a tone generator. The waveform memory has a plurality of storage areas, each of which is capable of storing a fixed bit-width data. In the case where the bit-width of the waveform data corresponding to a musical tone waveform is different from the bit-width of the data which can be stored in each storage area, the whole waveform data corresponding to the musical tone waveform are stored in the waveform memory so as not to allow the generation of empty areas which store no data. The waveform data may be divided if necessary and the divided parts of the waveform data are stored in some storage areas of the waveform memory.

Abstract: In case an instantaneous over-current flowing through switching elements is detected between a predetermined rise time point and a predetermined fall time point of each of the PWM control pulses, the output of the duty control circuit is stopped immediately. In other words, the duty factor of the PWM pulse signal to be outputted as it is under the normal conditions is reduced so as to be cut off after the over-current has been detected. Therefore, it is possible to protect the switching elements of the inverter from breakdown due to over-current, without stopping the operation of the compressor and the compressor motor.

Abstract: The invention relates to a supply system, with uninterrupted distributed storage, for sensitive operation systems supplied from the public electric energy distribution network (10) or an emergency power supply (11) producing an equivalent voltage, said system incorporating at least one short term energy reserve supply circuit (30) associated with each supplied system and a medium term energy reserve supply circuit (31) having a reaction delay below the autonomy delay of the short term energy reserve supply circuit.

Abstract: A single phase induction motor includes a start winding, a run winding coupled in parallel with the start winding, a start switch, and a run switch. A control circuit is provided for selectively supplying voltage to the start and run windings. A current sensor is coupled to the control circuit and the start and run windings for estimating the temperature rise of the motor and turning the motor off if overheated. An alternating voltage having a plurality of 360.degree. cycles can be continuously applied to the run winding through the run switch. The alternating voltage is repetitively applied through the start switch to the start winding in the range of 45.degree. to 135.degree. into each respective one of the plurality of cycles and ending at approximately 180.degree. into each respective cycle and beginning in the range of 225.degree. to 315.degree. into each respective cycle and ending at approximately 360.degree. into each respective cycle until the motor is running at a speed close to synchronous speed.

Abstract: A method and system for controlling operation of a brushless permanent magnet motor having stator windings in star configuration in which back EMF fundamental and third harmonic components are induced, a rotor which rotates relative to the stator windings, and an inverter operatively coupled to the motor to drive same, wherein a star configuration of resistors is coupled to nodes of the inverter and third harmonic components of the flux density of the motor are obtained from across an artificial neutral node present in a network coupled to the stator phase nodes and either the stator neutral node or a direct current midpoint reference node positioned between the direct current nodes of an inverter used to drive the motor. The network preferably is a stator network of resistors each of which is coupled between one stator phase node and the artificial neutral node.