Abstract: A controller for a switched reluctance motor is provided. The switched reluctance motor includes a rotor, a stator, and a coil wound on the stator. The switched reluctance motor is mounted on a vehicle as a drive source for propelling the vehicle. The controller includes an electronic control unit. The electronic control unit is configured to execute first control for exciting the coil at a first current value in a first exciting range. The electronic control unit is configured to, when the electronic control unit determines that the vehicle is not able to start moving even when the electronic control unit executes the first control, execute second control for exciting the coil at a second current value larger than the first current value in a second exciting range narrower than the first exciting range.

Abstract: The invention provides a drive control device that comprises: inverters that are connected to a motor; a variable resistive element that is connected between the motor and each of the inverters; a current/voltage detection device connected between the motor and each of the inverters; and a controller that, when detecting a fault of an inverter that drives the motor based on a detection signal from the current/voltage detection device, gradually increases a resistance value of a variable resistive element provided between the faulty inverter and the motor at a velocity of a resistance variation such that a surge voltage has a voltage value for which the variable resistive element and the motor are not damaged, and executes drive control of the motor by a normal inverter other than the faulty inverter.

Abstract: The invention provides a drive control device that comprises: inverters that are connected to a motor; a variable resistive element that is connected between the motor and each of the inverters; a current/voltage detection device connected between the motor and each of the inverters; and a controller that, when detecting a fault of an inverter that drives the motor based on a detection signal from the current/voltage detection device, gradually increases a resistance value of a variable resistive element provided between the faulty inverter and the motor at a velocity of a resistance variation such that a surge voltage has a voltage value for which the variable resistive element and the motor are not damaged, and executes drive control of the motor by a normal inverter other than the faulty inverter.

Abstract: A fan includes blades, a motor, a bracket fixing the motor, a fan connector, a resistor unit, and a switch unit. The fan connector, the resistor unit, and the switch unit are configured to control power to the motor to adjustably control rotation of the blades. The motor controls the blades to rotate at different speeds through switching the switch unit to adjust the current output to the power terminal of the motor.

Abstract: A rotation speed control device for a heat-dissipating fan includes an impedance unit, a regulating unit, and a driving circuit. The impedance unit includes a first resistor having a first end connected to a first node, and a second end connected to a second node, and a second resistor having a third end connected to the second node, and a fourth end. The regulating unit is connected to the impedance unit and is configurable for varying an effective impedance of the impedance unit to adjust magnitude of current flowing through the impedance unit. The driving circuit is connected to the impedance unit and is adapted to control rotation speed of the heat-dissipating fan according to the magnitude of the current flowing through the impedance unit.

Abstract: An electric fan includes a motor driving circuit, a controller, and a stepless speed-change device; the motor driving circuit is electrically connected to a blades-driving motor of an electric fan as well as a power circuit; the controller is electrically connected to the motor driving circuit while the stepless speed-change device is electrically connected to the controller therefore the rotational speed of the blades-driving motor of the electric fan can be adjusted in a stepless manner.

Abstract: A resistor member having a resistance value substantially equal to a resistance of a relay in an ON state is inserted into a current supply path which is not inserted with the relay in current supply paths for supplying currents from a driving circuit to a brushless motor. Further, in the driving circuit, widths of bus bars forming wirings are set such that resistances of the wirings (contact resistance) from a branch point on power source side to Hi side FET (source terminals thereof) are equal to each other and widths of bus bars forming the wirings are set such that the resistances of the wirings from a ground side branch point NL to Lo side FET (source terminals thereof) become equal to each other.

Abstract: An electric motor vehicle includes a battery that serves as a driving source for generating electric power, a pair of positive and negative electrode portions respectively connected to a positive electrode and a negative electrode of the battery, a resistor formed of a resistive material, and a first and a second contact portions connected to the resistor. The first and the second contact portion face the positive electrode portion and the negative electrode portion, respectively. The resistor is kept insulated from the battery in a normal operation state of the electric motor vehicle. At least one of the positive electrode, the first contact portion, the negative electrode and the second contact portion is displaced owing to an external force applied to the electric motor in an abnormal operation state such that the electrodes are in contact with their respective contact portions and the positive electrode and the negative electrode are short circuited in an abnormal operation state.

Abstract: A current control system for electric motor is disclosed. The system includes a controller, switches, and resistors. The system is located between the power source and the motor. These resistors are in series with the motor and in parallel to each other. These resistors are employed to change the total resistance between power source and motor, and the current is adjusted when the total resistance is changed. Each a specific resistance value is applied to adjust current, and the specific resistance value is provided by variety number(s) resistors. The controller controls all switches that connect to resistors. According to the working condition of motor, controller chooses corresponding resistors to adjust current. The current consumed by electric motor is varied in different case, but the net consumed current of motor and resistors is controlled and fixed in a predetermined region.

Abstract: The invention concerns an electromechanical device with variable resistance circuit serving to control a load. The device comprises a connection (10) for a source of power (12), a connection (14) apt to be connected to a load (16) supplied by the source of power (12), a resistance circuit formed by a plurality of branches (B.sub.1, B.sub.2, . . . B.sub.n) mounted in parallel between the connections (10, 14) and each comprising a resistance (R.sub.1, R.sub.2 . . . R.sub.n) in series with a switch (I.sub.1, I.sub.2, . . . I.sub.n) possessing an initial contact state and mechanical means comprising a carriage (20) moveable in translation between several predetermined positions, in each of which this carriage (20) is apt to co-operate with at least one of the switches (I.sub.1, I.sub.2, . . . I.sub.n) in order to modify its initial contact state and vary the intensity of the current traversing the load.

Abstract: A control circuit which permits a direct current motor to operate during traction or during braking in such a manner that energy can be either dissipated or recovered; and, in particular, the invention embodies gradual, continuous, and reversible shifting from one form of braking action to another.

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 speed control device for portable power tools having particular applicability to electric drills. The speed control device is adapted to automatically adjust the speed of the motor in accordance with changes in the diameter of the tool bit used. The device includes a sensor that senses the opening and closing of the jaws of the chuck. The sensor is mechanically coupled to a potentiometer circuit whose output signal is varied in accordance with movement of the sensor. The output signal of the potentiometer circuit controls the firing angle of a thyristor 34, which in turn controls the current supplied to the motor. In addition, the preferred embodiment includes a speed select switch which is connected to the potentiometer circuit to set the appropriate speed range for the motor, given the particular type of work material.

Abstract: A speed control device for the motor of a home sewing machine, comprising, a comparator having one input connected to a reference voltage, an output connected to the motor and another input, a first control circuit with a variable resistor connected to the other input of the comparator and a second control circuit with a low motor speed constant resistor and a switch connected to the same other input of the comparator.

Abstract: A four pole d.c. motor speed control is provided by connecting two of the opposed brushes together to ground and the intermediate brushes to separate terminals of a switch means which in energized positions connects a grounded power supply to at least one of the brushes. The switch means supplies various combinations including direct connection of the power supply to one or both of the brushes. Connection of the power supply through resistance means, connection of the other brush to provide a closed circuit across the windings or to provide a resistance in series with those windings.

Abstract: A control circuit for a direct current electric motor including a rectifying bridge for supplying the motor with direct current and a regulating circuit including a triac, the energizing angle of which is determined by a capacitor connected in series with a resistance network. An energy limiting circuit is provided including a resistance connectable in series with the resistance network and the capacitor when the voltage exceeds a predetermined value so that the motor can be operated on a 110 V or a 220 V supply.