Abstract: The medium winding device includes a winding shaft, a drive unit for winding the medium around the winding member, a rotating member rotatably disposed, a tension applying member which moves as the drive unit is driven or stopped, a position detecting unit for detecting the position of the tension applying member, an output changing unit, a control unit that determines whether slippage occurs between the winding shaft and the winding member based on the position of the tension applying member and the result of output change by a rotation of the winding shaft. Further, the drive unit includes a torque limiter.

Abstract: A rotating electrical machine including a stator or rotor including a plurality of serially connected switching cells. Each switching cell includes a winding subsection and a current reverser arranged to controllably alter a current direction through the winding subsection, and each current reverser includes a capacitor arranged to form a resonant circuit in cooperation with the winding subsection.

Abstract: A skin treatment apparatus, preferably an epilator, comprising at least one detector for detecting approximation and/or contact with the skin and a control unit to actuate the device depending on the signal received from the detector. The control unit has at least one regulator which increases the speed of the drive unit upon detection of an increased resistance and/or current consumption by a sensor and/or decreases the speed of the drive unit upon detection of an decreased resistance and/or current consumption by a sensor.

Abstract: A method of estimating electric motor speed. The method determines whether a sequential cycle of the electric motor has occurred. The method calculates a correction factor for each of the Hall states. Where a sequential cycle of the electric motor has occurred, the method also calculates an update quality factor for the correction factors of the sequential cycle. The method updates the correction factors utilizing the update quality factor. Utilizing the updated correction factors, the method updates the electric motor speed signal.

Abstract: An inverter drive device for driving a semiconductor switching element that controls an output current of an inverter. An inverter drive device includes a drive circuit configured to apply a drive voltage to the semiconductor switching element, to thereby turn the semiconductor switching element on and off, the turning off of the semiconductor switching element causing a counter electromotive force to be generated therein, a clamping diode configured to clamp a voltage of the generated counter electromotive force, a voltage dividing resistor configured to detect a voltage that is proportional to a current flowing through the clamping diode, and an auxiliary drive circuit configured to generate a control voltage in accordance with the voltage detected by the voltage dividing resistor, and to apply the control voltage to the semiconductor switching element, to thereby turn the semiconductor switching element on.

Abstract: A motor operating system includes a parameter-setting module and a control circuit. The parameter-setting module generates a first parameter-setting corresponding to a first operating stage through a user interface, and determines whether a first operating status conforms to a first threshold setting. The control circuit is coupled to a motor, receives the first parameter-setting corresponding to the first operating status, drives the motor according to a first driving signal corresponding to the first parameter-setting, and outputs the first operating status corresponding to the first driving signal. When the first operating status does not conform the first threshold setting, the parameter-setting module generates an adjusted first parameter-setting. When the first operating status conforms the first threshold setting, the parameter-setting module sets the first parameter-setting as a first optimal parameter-setting.

Abstract: The invention relates to an electric shaver (1) comprising a cutter unit (3), an electric motor (4) arranged to drive the cutter unit (3), a load detector (14) arranged to measure at least one electric parameter indicative of a power consumption of the motor (4) to obtain a measured value. An idle load calculator (16) receives one or more of the measured values measured at different instances during an idle period of the shaver. The idle load calculator calculates an idle load value using the one or more measured values, and stores the calculated idle load value in a memory (17). A threshold calculator (18) determines a cleaning threshold value. A comparator (19) generates a cleaning signal if an idle load value for the current shaving session exceeds the cleaning threshold value. An alerter (8) receiving the cleaning signal produces an alert indicating to a user that the cutter unit of the shaver should be cleaned.

Abstract: A vehicle traveling control apparatus includes a vehicle parameter detector, a vehicle parameter estimator, a disturbance-suppressing parameter calculator, an addition rate changer, and a disturbance suppressor. The vehicle parameter detector detects a vehicle parameter. The vehicle parameter estimator estimates, by means of a vehicle model, a vehicle parameter to be outputted in response to an input value. The disturbance-suppressing parameter calculator estimates, based on the vehicle parameters detected by the vehicle parameter detector and estimated by the vehicle parameter estimator, a disturbance generated at a vehicle, and calculates a disturbance-suppressing parameter. The addition rate changer identifies, based on the vehicle parameters detected by the vehicle parameter detector and estimated by the vehicle parameter estimator, the disturbance generated at the vehicle, and variably sets, based on the identified disturbance, an addition rate of the disturbance-suppressing parameter.

Abstract: A universal serial bus device includes: a core circuit having a first pin and a second pin, and having an input impedance looking into the core circuit from the first pin and the second pin; and a charging control circuit, coupled to the core circuit, arranged for providing a voltage source having a predetermined voltage to one of the first pin and the second pin and for providing a current source having a predetermined current to the other of the first pin and the second pin; wherein the input impedance of the core circuit is configured to make the predetermined voltage and the predetermined current substantially intact when an external charger charges a battery device of the universal serial bus device.

Abstract: A method is presented for controlling operation of a power tool having an electric motor drivably coupled to an output spindle. The method includes: receiving an input indicative of a clutch setting for an electronic clutch, where the clutch setting is selectable from a plurality of driver modes; setting the value of a maximum current threshold in accordance with the selected one of the plurality of driver modes; determining rotational speed of the electric motor; determining an amount of current being delivered to the electric motor; comparing the amount of current being delivered to the electric motor to the maximum current threshold; and interrupting transmission of torque to the output spindle when the amount of current being delivered to the electric motor exceeds the maximum current threshold and the rotational speed of the electric motor is decreasing.

Abstract: The invention relates to a method for detecting blocking or sluggishness (M1, M3) of a DC motor (2). The method comprises the following steps: applying a voltage pulse (Uv,t=Os) to the DC motor (2); monitoring a motor current (IMotor) flowing through the DC motor (2); detecting a maximum value of the motor current (IMotor) following the application of the voltage pulse; checking whether a change in the motor current (IMotor) after reaching the maximum value exceeds a specific amount; signalling the blocking or the sluggishness (M1, M3) of the DC motor (2) if the change in the motor current (IMotor) after reaching the maximum value exceeds the specific amount.

Abstract: A system and method for determining the start position of a motor. According to an embodiment, a voltage pulse signal may be generated across a pair of windings in a motor. A current response signal will be generated and based upon the position of the motor, the response signal will be greater in one pulse signal polarity as opposed to an opposite pulse signal polarity. The response signal may be compared for s specific duration of time or until a specific integration threshold has been reached. Further, the response signal may be converted into a digital signal such that a sigma-delta circuit may smooth out glitches more easily. In this manner, the position of the motor may be determined to within 60 electrical degrees during a startup.

Abstract: A method and a device for controlling and/or regulating an electric motor. Such electric motors are used for example in motor vehicles in the form of pump motors. In general, the electric motor is supplied with electrical energy from a battery and/or using a generator. The controlling and regulation take place using a high-frequency pulse width modulation (PWM). When the electric motor is started, the PWM is used to continuously increase the motor current required for the operation of the electric motor, e.g. beginning from 0.

Abstract: A universal control unit for driving a brushed or a brushless DC motor, such as the type commonly employed in a vehicle fuel pump or other vehicle application. According to exemplary embodiments, a universal control unit includes a processing device and an output stage, and is connected to either a brushed or a brushless DC motor in a manner that accommodates the two different motor types so that a common or universal controller can be used.

Abstract: A control system for an actuator including a straight slot direct current motor comprises a position sensor for measuring the angular position (?) of the motor and a current sensor for measuring the current strength (Im) in the motor, but not having a sensor for measuring the angular rotation speed of the motor.

Abstract: In an imaging apparatus having a toner container, a method of periodically calibrating a back EMF constant Ke used in a speed control circuit of a DC motor used for driving for a toner metering device. To adjust the value of the back EMF constant Ke, the method uses a plurality of sampled back EMF measurements together with a calculated actual speed of rotation of the toner metering device as measured using motion sensor.

Abstract: A fan controlling circuit is provided. The fan controlling circuit includes an integral unit, an operational amplifier, a PMOS transistor, and an NMOS transistor. The integral unit transforms pulse width modulation (PWM) signals to voltages, and transmits the voltages to positive and negative input terminals of the operational amplifier. The PMOS transistor is coupled between a first PWM signal and an output terminal, and a gate of the PMOS transistor is coupled to an output of the operational amplifier. The NMOS transistor is coupled between a second PWM signal and the output terminal, and a gate of the NMOS transistor is coupled to the output of the operational amplifier. The fan controlling circuit may be formed by discrete elements and use a same voltage source as fans, so that the design cost and complexity are reduced.

Abstract: A fan controlling circuit is provided. The fan controlling circuit includes an integral unit, an operational amplifier, and an output unit. The integral unit transforms pulse width modulation signals to voltages, and then the output unit outputs one of the pulse width modulation signals having a higher operation frequency according to the comparison result between the voltages. As the fan controlling circuit may be constituted with discrete elements and use a same voltage source as fans, the design cost and complexity are reduced.

Abstract: A DC motor assembly includes a motorized unit for generating a rotatable power at an output shaft, and a step adjusting control arrangement including an optical grating and a photocoupler. The optical grating, which is operatively coupled at the output shaft, has a plurality of light transmissible portions and a plurality of light blocking portions alternating with the light transmissible portions. The photocoupler is activated to send out an impulse signal in responsive to a phase shift between the light transmissible portion and the light blocking portion of the optical grating, wherein the output shaft is controllably driven to be rotated and stopped in a sequent manner as a stepping movement thereof in responsive to the impulse signal so as to controllably adjust the rotational speed of the output shaft.

Abstract: If a PWM duty instruction D1 determined by a duty calculation circuit exceeds an upper limit value, a duty signal processing circuit in a motor drive apparatus divides a switching current supply period in each of the phases into a first current supply period and a second current supply period. In the first current supply period, the duty is set to the upper limit value. In the second current supply period, the duty is set to 100%, and the length of the second current supply period is set depending upon the duty instruction.

Abstract: A drive system for an electrical machine is provided. The system includes a control unit and a monitoring unit, which is independent of the control unit. The control unit includes a device that converts one or more incoming operating parameters of the electrical machine to an output value. The monitoring unit includes a device that converts the operating parameters to a comparison value, with the conversion being carried out more quickly in the control unit than in the monitoring unit. A comparator compares the output value or an intermediate value of the output value with the comparison value of the output value or of the intermediate value.

Abstract: Provided are a method, computer-readable medium, and system for automatically determining a proper operational current input to an electric motor. In an exemplary embodiment, a method for determining the proper operational current input includes sending a test signal to an input of an electric motor. A response to the test signal is measured using an output of the electric motor. Based on the measured response, a position of a brush that is capable of conducting current through a commutator of the electric motor is determined. The electric motor is supplied with a first current input if the brush is in a first position and a second current input if the brush is in a second position.

Abstract: A direct current motor controlling apparatus may include a direct current motor driving unit to apply a driving voltage to a direct current motor and detect a predetermined signal from the direct current motor, and a servo-micom to control the status of the direct current motor using the signal detected by the direct current motor driving unit. Accordingly, the rotational status of the direct current motor is checked to control the direct current motor.

Abstract: A stepping motor controlling device according to the present invention includes lead angle computing means which computes a lead angle according to the load torque current deviation of the stepping motor, adding means which adds an angle command to the lead angle to determine a winding exciting angle and voltage applying means which applies a voltage according to the winding exciting angle to the stepping motor.

Abstract: A torque compensation method and system for a DC brushless motor. When the DC brushless motor coupled with an asymmetric load is rotating, the difference between an instant current and an average current of a shunt resister is an index of adjusting control signals within an absolute rotor position for the purpose of approaching the corresponding instant current to the average current.

Abstract: Systems and methods relating to a boosting rectifier and feeder motor drive circuit are provided. The circuit may be used to produce a regulated DC supply voltage from a variable input AC line voltage, chop the DC supply voltage and deliver a pulse width modulated motor voltage to a wire feed motor in the wire drive assembly. One embodiment relates to elimination of undesirable wire feeder inconsistencies due to motor loading conditions, distance between the primary power source and the wire feeder, and so forth. In certain embodiments, the circuit may contain power factor correction circuitry, which may reduce the size of circuit components due to increased efficiency. Current paths through the circuit during the positive and negative half cycles of the AC input voltage are provided. Exemplary controller logic that may be used to control the operation of the boosting rectifier and feeder motor drive circuit is provided.

Abstract: The rotation period of a motor is subdivided by edge interval times and a rate of change between a currently calculated edge interval time and an edge interval time calculated one rotation of the motor previously is calculated at the detection of each edge. Then the rotation period of the motor is calculated by multiplying a set reference period by the calculated rate of change.

Abstract: A method of constant airflow control for a ventilation system is disclosed. The method includes various controls to accomplish a substantially constant airflow rate over a significant change of the static pressure in a ventilation duct. One control is a constant I·RPM control, which is primarily used in a low static pressure range. Another control is a constant RPM control, which is primarily used in a high static pressure range. These controls requires neither a static pressure sensor nor an airflow rate sensor to accomplish substantially constant airflow rate while static pressure changes. This is because these controls use only intrinsic control variables which are electric current and rotational speed of the motor. Also, the method improves the accuracy of the control by correcting certain deviations that are caused by the motor's current-RPM characteristics. To compensate the deviation, the method adopts a test operation in a minimum static pressure condition.

Abstract: A mobile device includes a vibrator, an accelerometer that senses a parameter of rotation, and a processor. The vibrator includes a drive motor and a drive circuit. The accelerometer senses a speed of rotation of the vibrator. The processor analyzes the sensed speed of rotation and generates a drive voltage that is received by the drive circuit to adjust the drive motor to produce a pre-determined, desired rotational speed. In another embodiment, the accelerometer senses an amplitude of a vibration produced by the vibrator. The processor analyzes the sensed amplitude of a vibration and generates a drive voltage that is received by the drive circuit to adjust the drive motor to produce a pre-determined, desired vibration amplitude. The processor may also compare the sensed parameter with a pre-determined desired parameter of rotation and generate a signal responsive to a result of the comparison and based on stored vibrator calibration curves.

Abstract: An intelligent air moving apparatus for cooling an electronics enclosure includes a motor for driving a fan at a variable rotational speed and a microcontroller for controlling the rotational speed of the motor. The microcontroller includes a speed sensor for sensing the rotational speed such that when the sensed rotational speed deviates below a target speed, the microcontroller detects a locked rotor condition.

Abstract: An improved fan arrangement features a radial or diagonal fan (370) with which a direct current motor (32) is associated as its drive motor, further comprising a digital control element (23, 24) which executes a program, for controlling the current flowing through the direct current motor (32), which program is so configured that it applies a substantially constant current in the motor (32) in the working rotation speed range of the fan.

Abstract: General purpose 100% solid state Direct Current drive for rotary DC machines with four quadrants operation. It is to say that allows the rotary DC machine to act like motor or generator in the two direction of possible rotation. In the first and third quadrant as motor in both direction of possible rotation, and in the second and fourth quadrant like regenerative brake DC generator, recovering the energy towards the DC network supply. To obtain that generalized control for DC machines of any type, the invention subject of this patent, is based on the interaction of two original ideas that they are: (1) Maintaining the direction, of the current in one and only one of the two main windings of the DC machine (7) either field or armature, by means of a rectifier bridge (6). (2) Use a DC controlled power supply (14), with reversible polarity to feed the complete machine.

Abstract: A drive circuit for a sensored brushless DC motor, which has a rotably mounted rotor hub, comprises four legs. Each leg has a MOSFET and a diode configured to form four individual nodes. A first primary stator winding is coupled between the first and second nodes, while a second primary stator winding is coupled between the third and fourth nodes. A Hall sensor and an associated interface circuit which detects positions of magnets associated with the motor. As a result of the detected position, the drive circuit turns the MOSFETs on and off in a specified manner so as to rotate the rotor hub without the need for a snubber circuit.

Abstract: Provided are a method, computer-readable medium, and system for automatically determining a proper operational current input to an electric motor. In an exemplary embodiment, a method for determining the proper operational current input includes sending a test signal to an input of an electric motor. A response to the test signal is measured using an output of the electric motor. Based on the measured response, a position of a brush that is capable of conducting current through a commutator of the electric motor is determined. The electric motor is supplied with a first current input if the brush is in a first position and a second current input if the brush is in a second position.

Abstract: A hybrid electric lawnmower having dual power supply is described which includes an electric motor operating the blade and the ability to drive the motor from either 120 VAC line voltage or from a battery pack. There is a user selectable power selection switch for switching between DC or AC power in order to run the motor on either line voltage or based upon the charge of the battery pack.

Abstract: A hybrid electric lawnmower is described which includes an electric motor operating the blade and the ability to drive the motor from either 120 VAC line voltage or from a battery pack. There is a user selectable power selection switch for switching between DC or AC power and also a boost and conserve feature which allows for increased speed of the blade as necessary. Running the mower at the conserve setting prolongs battery pack duration per charge.

Abstract: A drive circuit for a sensored brushless DC motor, which has a rotably mounted rotor hub, comprises four legs. Each leg has a MOSFET and a diode configured to form four individual nodes. A first primary stator winding is coupled between the first and second nodes, while a second primary stator winding is coupled between the third and fourth nodes. A Hall sensor and an associated interface circuit which detects positions of magnets associated with the motor. As a result of the detected position, the drive circuit turns the MOSFETs on and off in a specified manner so as to rotate the rotor hub without the need for a snubber circuit.

Abstract: The invention discloses a power tool for screwing or drilling having a motor for driving a drive shaft, a controller for controlling the power tool, a motor switch for switching the motor on and off, switch for reversing the power tool between clockwise and counter-clockwise rotation, and vice versa, and a timer that permits reversal of the power tool between clockwise/counter-clockwise rotation, and vice versa, within a predefined period of time between actuation of the switch for clockwise/counter-clockwise rotation and for operation of the motor switch to start the power tool.

Abstract: General purpose 100% solid state Direct Current drive for rotary DC machines with four quadrants operation. It is to say that allows the rotary DC machine to act like motor or generator in the two direction of possible rotation. In the first and third quadrant as motor in both direction of possible rotation, and in the second and fourth quadrant like regenerative brake DC generator, recovering the energy towards the DC network supply. To obtain that generalized control for DC machines of any type, the invention subject of this patent, is based on the interaction of two original ideas that they are: (1) Maintaining the direction of the current in one and only one of the two main windings of the DC machine (7) either field or armature, by means of a rectifier bridge (6). (2) Use a DC controlled power supply (14), with reversible polarity to feed the complete machine.

Abstract: A power tool is disclosed comprising a controller for controlling at least one operating parameter, a motor for driving a tool, at least three switching elements which are coupled to the controller, and a speed sensor for monitoring the speed of the motor to generate a speed signal, which is fed to the controller. The controller is configured so that, in dependence on the speed signal, with simultaneous activation of a first and at least one other of the switching elements, a control signal for changing the operating parameter is output, and that, in dependence on the speed signal, with activation of the first and at least one other switching element, a control signal for modified changing of the operating parameter is output (FIG. 2).

Abstract: A multiple axis servo control implements a multi-tasking PWM control unit to provide PWM signals for multiple axes in a single unit. A time slice mechanism provides axis selection signals based on a system clock signal to permit control parameters of the selected axis to be processed to control the selected motor drive axis. The single unit PWM control mechanism eliminates complex and costly multiple axis networks typically associated with independent servo motor controls for each axis in a multi-axis system. A single PWM unit implementation also permits the reduction of components for closed loop current control and closed loop velocity control in the multi-axis servo control system.

Abstract: A motor control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a waveform-shaping circuit connected between the PWM signal generating circuit and the driving circuit. The PWM signal generating circuit generates a square wave with a sequence of alternating on-time and off-time. The waveform-shaping circuit adjusts the rise-time and the fall-time of the square wave to be both within a range of 5% to 15% of the square wave period, and the driving circuit outputs a driving signal to a fan motor according to the adjusted square wave.

Abstract: A system and method for measuring fluid flow rate in a system where fluid is pumped, such as a gas monitoring instrument where gas is pumped from a space such as a room or enclosure through a conduit to a sensor. The flow of gas through a pump is determined by measuring motor back-e.m.f. which is proportional to motor speed. In a system where motor speed is regulated by pulse width modulation of the motor drive voltage, the back-e.m.f. is sampled during intervals between the drive pulses applied to the motor, and in a further aspect the sampling is done at selected, spaced-apart or infrequent intervals such as once for every ten or once for every hundred motor drive pulses. Advantageously, in an instrument that uses a microprocessor and analog-to-digital converter to measure gas-concentration, the same microprocessor and converter can provide the PWM control of the pump, in response to the back-e.m.f. generated by the pump motor between the drive pulses.

Abstract: In a control apparatus for a motor, which rotates a fan, a semiconductor device is connected to the motor in series to drive the motor. An analog driver circuit drives the semiconductor device with an analog voltage. A PWM control circuit drives the semiconductor device with a PWM signal of a frequency of less than several tens. A switching control circuit selects the analog driver circuit and the PWM control circuit when the motor is to be rotated at speeds lower and higher than a predetermined speed, respectively.

Abstract: A control system for a powered wheel chair drive modulates a pulse power delivery signal such that power is delivered gradually at throttle positions corresponding to a low speed, and power is delivered more rapidly at throttle positions corresponding to a higher speed.

Abstract: A vector control device of a winding field type synchronous machine with which even when voltage changes caused by resistance voltage falls and inductance fluctuations due to armature current occur the armature voltage is controlled exactly to a desired command value and a high power supply utilization percentage is maintained at all times. An absolute value of armature voltage is calculated from an armature voltage command value or an armature voltage detected value, and the armature voltage is controlled by a flux command being regulated so that this absolute value of armature voltage approaches a desired armature voltage command value. Also, the armature voltage command value is regulated so that the loss of the synchronous machine becomes minimal with reference to the armature current and the field current.

Abstract: The invention relates to a method to optimize the efficiency of a motor operated under a load having an essentially quadratic characteristic curve, the motor being connected to a motor control with whose aid at least one free motor parameter w can be changed to influence the efficiency. According to the invention, the rotational speed n and the input power PE are determined and the motor parameter w is adjusted to a value at which the value E representing the quotient of the cube of the rotational speed n and the input power PE attains a maximum.

Abstract: A device for correcting a digital estimate of an electric signal is described. The device includes a comparator that generates a current proportional to the difference between an analog estimate signal, which derives from the digital estimate, and the electric signal. The device also includes a capacitor positioned to be charged by the current, a transistor that discharges the capacitor, and a comparator that compares the voltage at the terminal of the capacitor with a reference voltage. The device also includes a controller that drives the transistor in response to the output signal of the comparator and a logic device that generates a correction digital signal to be added to or subtracted from the digital estimate of the electric signal in correspondence of an ascending or descending waveform of the electric signal.

Abstract: A device of a cart includes a control, a speed regulating potentiometer, a microprocessor, a digital-to-analogue converter, a motor controlling unit, and a switch; the control is angularly displaceable and near to handlebars of the cart; the potentiometer is connected to the control so as to output a voltage, which depends on displacement of the control; the microprocessor can produce digital signals according to the output voltage of the potentiometer; the converter is used for converting the digital signals into analogue voltage; the motor controlling unit is used for making a motor run at a variable-speed mode, at which mode the speed of the motor will depend on output voltage of the converter; immediately after the rider presses the switch, the microprocessor will ignore output voltage of the potentiometer, and start and continue giving a same digital signal to the converter so that the motor starts running at constant speed.

Abstract: A commutation and velocity control system of a brushless DC motor receives a velocity command signal and provides command signals to drive the brushless DC motor. The system includes a summer that receives the velocity command signal and a velocity feedback signal and provides a velocity error signal indicative of the difference. A velocity loop compensator receives said velocity error signal and provides a compensated velocity error signal. A magnitude sensing circuit senses the magnitude of said compensated velocity error signal and provides a velocity magnitude signal indicative thereof. A polarity sensing circuit senses the polarity of the said compensated velocity error signal and provides a velocity polarity signal indicative thereof.