Abstract: A motor driver has a braking control circuit. The braking control circuit shuts off the supply of an electric current to the coils included in the motor when a motor control signal shifts to a predetermined level and, after a predetermined length of time secured in accordance with an index signal, starts application of braking to the rotation of the motor by the use of a braking circuit. The index signal is obtained from the signal that indicates the rotational position of the motor. The motor control signal is fed from a control signal generating circuit to the braking control circuit.

Abstract: In a photointerrupter comprising a light emitting diode and a photo transistor which are opposed to each other, the photo transistor has an emitter which is grounded through a resistor while the light emitting diode has a cathode which is connected to an input terminal of a one IC chip for controlling a flexible disk drive. The one IC chip incorporates a constant current source which is connected to the input terminal through an npn-type bipolar transistor. The one IC chip incorporates a logic circuit having an output terminal which is connected to a base of the npn-type bipolar transistor.

Abstract: A fume hood exhaust terminal for controlling gas flow in an exhaust duct has an electrically powered ultrasonic motor driven actuator for angularly positioning a damper in the terminal. The circuitry of the terminal includes a power failure detection circuit which includes the capability of storing sufficient power to place the damper in a preferred position until power is restored to the exhaust terminal.

Abstract: In an integrated circuit for use in controlling a flexible disk drive for driving a flexible disk loaded therein, a power on reset circuit produces a reset signal after a predetermined time duration elapses where a power supply voltage is stable from a time when a power supply is applied. The power on reset circuit comprises a voltage detecting circuit for detecting a power supply voltage to produce a voltage detected signal and a delay circuit for producing, responsive to the voltage detected signal, the reset signal after the predetermined time duration elapses. Disposed between a selectable function circuit and a logic circuit, an output holding circuit holds output signals of the selectable function circuit as held signals and supplies the held signals to the logic circuit. The output holding circuit consists of two D-type flip-flops which are disposed in correspondence with two output signal lines of a logical circuit.

Abstract: A method of preventing a wire from becoming entangled in a reinforcing bar fastening machine having a wire feed device for feeding a wire for fastening reinforcing bars, a guide arm for guiding the wire so as to wind around a crossing point of the reinforcing bars in the form of a loop, a twisting device for performing a tying operation by twisting while picking up part of the loop of the wire wound around the crossing point of the reinforcing bars, and a cutting device for cutting the loop from the wire on a reinforcing bar fastening machine side, the method comprises the steps of: monitoring a torque of a motor for driving the twisting device; and stopping the operation of the twisting device when no increasing tendency is observed in changes in the torque after a predetermined time has elapsed from an operation start timing of the twisting device.

Abstract: A brushless dc motor having 3-phase stator windings and a permanent-magnet rotor is driven on a dc voltage through a 3-phase electronic switching circuit. Back emf voltages across the stator windings are individually phase-delayed and the phase-delayed voltages are individually compared in comparators with a common sawtooth-wave comparator reference voltage having a frequency proportional to a current rotor speed and an amplitude whose center voltage is one-half of the motor driving dc voltage. A drive control unit, a microcomputer, transmits to the switching circuit switching control signals in sequential driving steps according to 3-phase output signals of the comparators so that the switching circuit performs commutation of the motor drive voltage in a first motor driving mode. The time constant of the phase-delay circuits is increased when the rotational speed of the rotor is below a predetermined speed or the motor driving current is above a predetermined level.

Abstract: When a window glass catches an obstacle and driving current of a driving motor increases to a set maximum value, the driving current is controlled within the maximum set value to limit the obstacle catching force. Because the motor is controlled by a duty ratio of PWM signal, the motor speed can be controlled with ease and stable control of the motor is ensured.

Abstract: A method and apparatus for controlling an AC motor are described wherein a frequency generator is configured to generate a signal representative of the stator electrical frequency and to estimate the rotor electrical frequency of the motor during operation. The generator operates on torque and flux current reference signals and on d-axis voltage reference and feedback signals to determine the electrical frequencies. The generator ramps up gain values applied to the torque current reference signals and to a voltage error signals representative of the difference between the d-axis voltage reference and feedback signals during a startup phase of operation to enhance performance and stability of the drive during this phase. The generator includes feedforward and feedback portions that contribute components of the final stator frequency signal. The components are filtered differently during startup and running phases of operation to provide the desired frequency signals.

Abstract: Methods and apparatus for controlling energization of an appliance motor are described. The apparatus, in one embodiment, may include a condition responsive switch secured within an appliance motor casing to control the energization of the appliance motor windings. In one mode of operation, the condition responsive switch substantially prevents energization of the motor windings if at least one attachment has not been substantially properly secured to the appliance, and the switch substantially properly secured to the appliance.

Abstract: The invention relates to a device for controlling a mechanism driven by at least one electric motor (11, 12), said device comprising a circuit (20, 38) for detecting the power consumption of the mechanism and for comparing the detected value with at least one current threshold, with confirmation during a defined time and a circuit (54) for controlling the stopping of the mechanism for a given time, as a function of the result of said comparison.Application more particularly to the field of high-capacity or wide-body aircraft, for the generation of pressure in their hydraulic circuits.

Abstract: A system for controlling actuating members in the doors of motor vehicles has at least one electromotive actuating drive and at least one actuating element (switch, button) in the door of the motor vehicle, as well as a control unit located in the vehicle itself. The system employs only a two-wire connection between control unit and actuating drive. The control unit, in addition to an ordinary pole-reversing and evaluation circuit, furthermore contains a source of alternating voltage as well as means for connecting the alternating voltage and a decoder. At least two passive components (resistor, capacitor, coil) of different size are provided to be connected by the actuating element in parallel with the actuating drive into the two-wire connection.

Abstract: An apparatus for controlling a drive circuit having a supply of electric power from a power source to drive an electric motor. The drive circuit includes at least one switching element operable between a first state connecting the electric motor to the power source and a second state disconnecting the electric motor from the power source in the second state. An overcurrent detection signal is produced when the current flow through the electric motor exceeds a predetermined value. In the presence of the overcurrent detection signal, the switching element is changed to the second state. The switching element is fixed in the second state when the repetitive period of the overcurrent detection signal is less than a predetermined value to avoid an excessive amount of heat generated from the switching element because of transient power losses.

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: An electrically operated actuator stores power in a capacitor for returning the actuator output element to a preselected position upon power failure. The actuator has a controller having input power terminals connected across the capacitor and control terminals for controlling the power applied from the input power terminals to the motor which comprises the actuator's prime mover. A sensor monitors the presence of power provided to the controller's input power terminals. When failure of this power is sensed, the capacitor current flows to the controller, and the sensor applies signals to an override circuit of the controller causing the controller to apply current from the capacitor to the actuator motor in a way which drives the actuator toward the preselected position. A properly selected capacitor is capable of supplying adequate current over a period of time sufficient to return the actuator to the preselected position.

Abstract: In an elevator having a converter which changes an A.C. output from an A.C. power source into a D.C. output, an inverter which changes the D.C. output of the converter into an A.C. output, a current detector which detects an output current of the inverter, and an inverter controller which controls the inverter on the basis of the detected current value of the current detector and a command current value, a hoist motor being driven by the A.C. output of the inverter; the operation of the inverter being stopped when a difference between the detected current value and command current value of the current detector for detecting the output current of the inverter exceeds a preset value. Accordingly, a current detector for detecting current flowing through the inverter is dispensed with, to realize a simple arrangement and a low cost.

Abstract: A control system for operating a bidirectional gate driven by a reversible electric motor includes an overload protection circuit to prevent motor current overload produced by gate obstructions and the like. The system includes control switches for operating gate opening and gate closing circuits which respectively energize the motor for rotation in opposite directions. The safety circuit includes a motor current sensing device and a first comparator which compares the level of sensed motor current with a temperature adjusted, selectable reference value and delivers a motor disabling signal to the opening and closing circuits if the sensed value exceeds the reference level. The safety circuit also includes a second comparator which compares the sensed current level with another reference value to produce the disabling signal in the event that the selected reference value of the first comparator is incorrect.

Abstract: A device for detecting opposite phases and an open phase in an input three-phase voltage for a DC motor, wherein the input three-phase voltage is rectified by a three-phase bridge circuit and supplied to the armature of the DC motor. The input three-phase voltage is supplied to the three-phase bridge circuit when the maximum level is equal to or less than the reference voltage, while the input three-phase voltage is not supplied to the bridge circuit when the maximum level is greater than the reference voltage. In this case, both opposite phases and an open phase can be detected by using a common device. In addition, only two phases, such as U- and W-phases, are used for detecting opposite phases and an open phase no matter how these phases may be generated in any phase such as U-, V- or W-phase of the input three-phase voltage. As a result, the device is small in size, simple in electrical construction and low in cost.

Abstract: A system is provided to control a load responsive to a maximum load condition to disable the load when the maximum load condition exists, the control being altered first to provide a period of non-response during load start up and secondly to provide temperature compensation over a very wide temperature range and more particularly where the load device is a motor means for linearly reciprocating a closure member such as a sun roof, a window or a door, particularly for a vehicle such as an automotive vehicle.

Abstract: A delayed turn-on and turn-off control circuit for an electric motor includes a motor relay having an electrical actuator and a normally open motor contactor which is connected in series between the motor and an electrical power source for running the motor when the electrical actuator is energized. A normally non-conductive electrical switching device is serially connected between the electrical actuator and the power source. A turn-on delay circuit is responsive to closing of a normally open motor start switch and produces an electrical signal to render the electrical switching device conductive only after a predetermined lapse of time following the closing of the motor start switch, thereby energizing the motor.

Abstract: A method and apparatus for connecting a rotary drum drive, particularly a rotary drum drive of a rotary furnace or kiln, after disconnection for a short time, and before standstill of the oscillating drum, features detecting the movement of the oscillating drum and connecting the drive motor at a turning point of the oscillation or upon agreement with the direction of movement and the driving direction.

Abstract: In a friction-fusion apparatus a solid state control circuit including a triac connected in series with an electric motor, and a control circuit connected across said triac including a resistor and a capacitor and a diac connected between the junctions thereof and the gate electrode of the triac. A voltage control circuit across the capacitor normally limits the voltage across the capacitor to an amplitude insufficient to trigger the diac and is operative in response to a manually actuated switch to increase that voltage, thereby triggering the diac and rendering the triac conductive to operate the motor for a selected time interval.

Abstract: An electronic control circuit for automatically stopping the tape drive motor of a magnetic tape recording and playing unit. A set of contacts is provided in the circuit to detect electrically conductive means located at preselected points along the magnetic tape, and upon such detection, to alter the conductive states of three control transistors to cause de-energization of the tape drive motor. Diode logic means in the circuit prevent automatic stopping of the drive motor when the recording and playing unit is operated in a particular mode wherein such stopping is not desired.