Abstract: A method for controlling a fan speed of an electronic apparatus and the electronic apparatus using the same are provided. The method includes: detecting an input voltage, an output current, and a working temperature of the electronic apparatus; calculating a target speed of the fan according to the input voltage, the output current, and the working temperature; providing a speed control signal indicating the target speed to drive the fan and obtaining a fan speed signal indicating an actual speed of the fan; and performing a close-loop control based on the fan speed signal, so that the actual speed is adjusted to the target speed.

Abstract: A power control circuit includes: a differential voltage monitor configured to monitor a differential voltage between a first voltage and a second voltage, and control a switching element to be turned on and off, wherein the differential voltage monitor controls the switching element in such a manner that in a case where the differential voltage is increased, when the differential voltage is lower than a first reference voltage, the switching element is turned off, and when the differential voltage is equal to or higher than the first reference voltage, the switching element is turned on, and in a case where the differential voltage is decreased, when the differential voltage is higher than a second reference voltage, the switching element is turned on, and when the differential voltage is equal to or lower than the second reference voltage, the switching element is turned off.

Abstract: To provide a motor control circuit that variably controls the speed of a motor, in which an appropriate advance angle value corresponding to the speed of the motor that is set can be automatically set. The motor control circuit according to the present invention includes an advance angle setting means that adds a reference advance angle value to an advance angle correction value obtained by multiplying a proportional coefficient by a correction amount and outputs an advance angle setting signal, and an advance angle setting correction means that uses a ratio of a correction reference period relative to a period of a reference signal input from the outside as a correction amount and corrects the reference advance angle value by an advance angle correction value obtained by multiplying the correction amount by a predetermined proportional coefficient of the advance angle setting means.

Abstract: A system and method for controlling an operation of a power door of a vehicle are presented. An activation of a user interface device associated with the power door is detected. A cue is provided using a notification device after detecting the activation of the user interface device. In one implementation, the notification device includes an audible alarm. When the user interface device is activated for greater than a predetermined time period, the power door is caused to be in a power mode of operation, and the notification device is used to indicate a current operational mode of the power door. In one implementation, when the user interface device is deactivated within the predetermined time period, the power door is caused to be in a manual mode of operation.

Abstract: A method for controlling the operation of an arrangement of at least two electric machines coupled to different wheels of a motor vehicle and connected to a battery which provides an actual minimum and maximum limiting current for the electric machines. Desired torques are provided for the electric machines by a drive control logic. A desired current resulting from the desired torque is ascertained for each electric machine, and the sum of the desired currents are compared with the maximum and minimum limiting current. If the sum lies outside an interval defined by the limiting currents, the desired currents are adjusted using at least one change rule such that the sum of the desired currents lies within the interval. Adjusted desired torques are determined from the adjusted desired currents and used to control the electric machines.

Abstract: In a vehicle door, an opening/closing control device is provided. In the device, a controller is connected to an input current path connected to a vehicle battery. By a switching relay circuit, electricity is supplied from the vehicle battery to a closing motor or a release motor selectively. Between the switching relay circuit and the closing motor, a closing relay circuit is provided. If electricity is supplied to the closing motor, the closing relay circuit will be switched to ON where electricity is supplied to the closing motor or OFF where electricity is not supplied to the closing motor.

Abstract: A fan control system includes a first fan, a second fan that is adjacent to the first fan, a first motor that is configured to rotate the first fan, a second motor that is configured to rotate the second fan, and a control unit. The control unit is configured to control the rotational speeds of the first motor and the second motor, and to decrease the rotational speeds of both the first motor and the second motor when the rotational speed of the first motor must be decreased.

Abstract: A driving force transmitting device for driving a driven unit includes a first driving unit, a second driving unit, a driving force-transmitted portion which is attached to the driven unit and to which driving forces of the first and second driving units are transmitted, and a controlling unit for separately controlling the first and second driving units, wherein driving force transmitting portions of the first and second driving units transmit the driving forces to the driving force-transmitted portion at its different positions, and wherein when the driven unit being driven is to be stopped, the controlling unit causes the first driving unit to drive in a direction reverse to a driving direction while the second driving unit continues to drive, then causes the first and second driving units to stop in a state in which the driving forces of the first and second driving units are balanced with each other.

Abstract: When it is determined that a rotor is initially in a stationary state, a current vector is applied to a coil by a vector control method so as to rotate the rotor in a forward direction from a present position of the rotor regardless of a predetermined start position of the rotor. Therefore, a motor can be stably started with less power consumption and noise/vibration.

Abstract: A first motor generator-control unit (MG1-ECU) and a second motor generator-control unit (MG2-ECU) are provided independently for respective motor generators. The MG2-ECU performs electric power balance control by correcting an MG2 torque command value as required, so that the sum of the MG1 electric power and the MG2 electric power is within a range of allowable input/output electric power of a DC power supply. The electric power balance control is performed using an estimate of the MG1 electric power based on data obtained by the MG1-ECU. The estimate is determined so that a communication delay time between the MG1-ECU and the MG2-ECU is corrected. In this way, the electric power balance control can be performed appropriately for restricting, within a predetermined range, the total input/output electric power of the electric motors as a whole of a hybrid vehicle mounted with a plurality of motor generators (electric motors).

Abstract: A power limiting system for multiple electric motors includes an electrical power generating component, such as an alternator, and a plurality of motor controllers connected to an electrical bus. Each motor controller compares the voltage on the bus to a specified minimum voltage and a specified maximum voltage, and reduces its electric power output if the voltage on the bus is less than the maximum voltage while continuing to operate the electric motors.

Abstract: A method of controlling a web in, for example, a web cutter that minimizes the destructive forces that are experienced by the web. The method includes providing a motor system for driving a web handling mechanism structured to move the web, wherein the motor system includes a motor and a motor control subsystem having a digital filter (such as a PID controller or some other suitable closed loop controller), detuning the digital filter, and using the motor system having the detuned digital filter to drive the web handling mechanism.

Abstract: An integrated skid system integrates the functions of multiple skids into a single skid to reduce the skid footprint and the complexity of the overall system. A multi-motor controller monitors the devices on the integrated skid to maintain proper temperature, pressure and current draw in the devices. Base on this information, the multi-motor controller can make decisions on faults and fault accommodation and communicate with a main controller regarding the operating states of the skid devices via a single serial or Ethernet-type connection.

Abstract: A method for controlling a wheel speed of a locomotive includes determining an estimated wheel speed (52) for a desired wheel set of a locomotive responsive to a locomotive operating parameter indicative of an actual wheel speed of the desired wheel set. The method also includes generating a first adjustment parameter (e.g., 46) based on an operating condition of the locomotive, and then applying the first adjustment parameter to the estimated wheel speed for generating a first adjusted estimated wheel speed signal (54) used as a first input for controlling a wheel speed of at least one of the desired wheel set and the other wheel sets of the locomotive.

Abstract: A power monitoring apparatus for receiving an external input signal includes a first modulating unit, a second modulating unit and a comparing unit. The first modulating unit receives and modulates an input signal into a first signal. The second modulating unit receives and modulates the input signal into a second signal. The comparing unit is electrically connected with the first modulating unit and the second modulating unit and has a first input terminal, a second input terminal and an output terminal. The first input terminal receives the first signal and the second input terminal receives the second signal. When a difference between the first signal and the second signal is higher or lower than a predetermined range, the output terminal outputs a control signal.

Abstract: A motor control device includes a velocity detection unit, a motor control unit, a phase difference detection unit, and a correction value calculation unit. The velocity detection unit detects each velocity of a plurality of driven bodies or of a plurality of motors which independently drives a corresponding one of the driven bodies. The motor control unit independently controls each of the motors based on the velocity and a predetermined velocity directive value. The phase difference detection unit detects a phase difference among each of the driven bodies. The correction value calculation unit calculates a correction value for the velocity or the velocity directive value based on the phase difference.

Abstract: An automatic clothes dryer comprises a cabinet in which is rotatably mounted a drum that defines a drying chamber and a motor for rotating the drum. A variable speed blower is mounted within the interior space and is fluidly coupled to the drying chamber for moving air through the drying chamber at varying flow rates to improve the drying of the clothes.

Abstract: A method for controlling a fan is provided for adjusting the rotational speed of a fan. The method includes adjusting the rotational speed of the fan from a first mode value to a range of rotational speed variation, wherein the upper bound of the range of rotational speed variation is a second mode value plus a first variation value, and the lower bound of the range of rotational speed variation is the second mode value minus a second variation value; and adjusting the rotational speed of the fan in the range of rotational speed variation during a time period. Thus, a user will not consider the sound from the fan as a noise.

Abstract: A brushless motor according to the present invention provided with a recording disk in a rotational member and serving to rotate the recording disk together with the rotational member comprises a first position detecting means for detecting a rotational position of the rotational member, a second position detecting means for detecting a rotational position of the recording disk, wherein a mode for rotating the rotational member at a high speed by a detection signal of the first position detecting means and a mode for rotating the rotational member at a low speed by a detection signal of the second position detecting means are generated. Thereby, the two rotation states whose rotation speeds are different can be obtained in a simplified constitution.

Abstract: An electronic control system (24) for a vehicle seat is provided that includes a seat base (12), a seat back (14), an operator input device (30) and a control circuit (26). The seat base has a seat back motor (34) configured to move a seat base forward and backward. The seat back has a seat back motor (32) configured to adjust an angle of inclination of the seat back. The operator input (30) device is configured to received operator commands for movement of the vehicle seat. The control circuit is configured to receive the operator commands and to control the seat base motor and the seat back motor. The control circuit is also configured to move the seat base and the seat back at a ratio of approximately 1 degree of inclination to between approximately 1 mm to approximately 4 mm of forward or backward movement of the seat base.

Abstract: A drive unit for controlling a motor includes a position feedback device and a velocity noise filter. The position feedback device is operable to generate a position signal relating to a position of the motor. The velocity noise filter is coupled to the position feedback device and operable to filter the position signal over a predetermined number of samples to generate a velocity feedback signal for the motor.

Abstract: An electronic control system (24) for a vehicle seat is provided that includes a seat base (12), a seat back (14), an operator input device (30) and a control circuit (26). The seat base has a seat back motor (34) configured to move a seat base forward and backward. The seat back has a seat back motor (32) configured to adjust an angle of inclination of the seat back. The operator input (30) device is configured to received operator commands for movement of the vehicle seat. The control circuit is configured to receive the operator commands and to control the seat base motor and the seat back motor. The control circuit is also configured to move the seat base and the seat back at a ratio of approximately 1 degree of inclination to between approximately 1 mm to approximately 4 mm of forward or backward movement of the seat base.

Abstract: The invention provides an electrically movable vehicle drivable by a simplified mode of control and a control program for driving the vehicle. A normalized value Y? representing translation motion and a normalized value X? representing turning motion are fed from a command value input unit 110 to a velocity command value calculating unit 120. The calculating unit 120 determines a translation velocity command value Vg—trg based on the normalized value Y?. The calculating unit 120 determines a turn angular velocity command value ?f—trg that will always satisfy Expression (2–4) for preventing the vehicle from falling down. The translation velocity command value Vg—trg and the turn angular velocity command value ?f—trg determined by the unit 120 are fed to a control command value calculating unit 130, which calculates control command values for left and right drive wheels. The control command values are fed to a motor control unit 140 to control motors Mr, Ml and control the drive wheels.

Abstract: The present invention discloses an apparatus for compensating for a speed error of a motor which can reduce a speed ripple of the motor resulting from load characteristics, and which also can reduce vibrations and noises. The apparatus for compensating for the speed error of the motor divides a rotational section corresponding to one complete revolution of a rotor of the motor into a plurality of preset rotational sections, determines a speed compensation value in each divided rotational section on the basis of a difference value between a reference speed and a previous estimated speed, and compensates for the speed error of the motor on the basis of the speed compensation value.

Abstract: In a motor and a disk drive apparatus in accordance with the present invention, a position detecting part 30 comprises a detection signal switching circuit 39A, a noise elimination circuit 38 and a detection circuit 39B, and the detection signal switching circuit 39A is configured to output an inverted detection signal obtained by logically inverting a detection signal until the rotation speed reaches a predetermined rotation speed after the beginning of starting or until a position detection pulse signal FG is detected a predetermined number of times; position detection operation is carried out only during the ON operation of PWM, whereby PWM sensorless starting is carried out.

Abstract: A driving control device for an actuator comprises a driving device to drive an actuator having an electric motor (30) and a driving control device (50) to control the rotation of the electric motor (30) by controlling the driving device. The driving control device includes an H bridge circuit constructed by four switching semiconductor elements (Tr1 to Tr4), and rotates the electric motor in normal and reverse directions by turning on and turning off the switching semiconductor elements (Tr1 to Tr4). The driving control device (50) conducts to activate and to stop the electric motor (30) by applying a PWM signal to the switching semiconductor elements (Tr3 and Tr4) constructing the lower arm of the H bridge circuit (51).

Abstract: There are provided as drive sources an engine 2, a front motor 3 provided on a front wheels 8 side of the vehicle and a rear motor 4 provided on a rear wheels 9 side of the vehicle, and in executing a regeneration of deceleration energy when braking, a regeneration capacity of the front motor 3 and a regeneration capacity of the rear motor 4 are calculated, respectively, so that the regeneration is executed with either of these motors 3, 4 which can provide a larger regeneration capacity.

Abstract: In determining a starting point of a motor of an electric actuator during its initialization procedure, when a rotation angle sensor detects pulse signals in a certain initialization pattern, power supply to the motor is stopped by the control of a motor drive circuit. This electrical control of motor rotation enables the initialization procedure of the actuator to be carried out without using mechanical restriction means for locking purposes, and the influence of variations in the deflection amount of any stoppers is eliminated. The precision in determining the starting point in the initialization procedure is thus improved.

Abstract: A ventilator having an abnormal operation indication device includes a power supply circuit, a central processing unit, a fan motor, and a load sensing circuit. Thus, the load sensing circuit detects the abnormal operation signals through the sensor, so that the abnormal operation indication lamp on the panel of the ventilator lights, so as to indicate that the part of the ventilator is disposed at an abnormal operation state and needs to be inspected and amended, thereby facilitating inspection and maintenance of the parts of the ventilator.

Abstract: An electric vehicle driven by electric motors is provided. The vehicle is switched between forward travel, neutral and reverse travel by a directional speed lever which allows adjustment of the vehicle speed. When the directional speed lever passes through a neutral region at a high speed during forward travel of the vehicle, the vehicle is controlled to shift to normal reverse operation after a lapse of a predetermined period of time since the rotational speed of the electric motors becomes zero, thereby to avoid application of a heavy load to drive circuits for the electric motors.

Abstract: An electric vehicle driven by a pair of left and right electric motors is provided. The vehicle includes a controller for controlling the start of the vehicle. The controller performs such control as avoiding brake drag caused by the operation of the electric motors before the elimination of the braking of a pair of left and right parking electromagnetic brakes.

Abstract: A washing machine motor drive device drives a motor using an inverter circuit, which implements a constant torque control through a change in the torque-revolution speed characteristic of the motor. This facilitates an easy control of braking torque (negative torque), thereby providing a maximized braking torque. An easy control of regenerative energy is also provided, and back electromotive force is consumed by the internal resistance of the motor. Practically described, DC power of a rectifier circuit connected to an alternating current source is converted by an inverter circuit into AC power for driving the motor for operating an agitator or a washing/spinning tub. Motor rotor position is detected by rotor position detector, motor current is detected by current detector, and a control device controls the inverter circuit for resolving the motor current into a current component corresponding to magnetic flux and a current component corresponding to torque.

Abstract: Control section determines necessary acceleration of a transporting section in accordance with an actual transporting speed, and also determines a correction coefficient corresponding to the number of rotations of an engine from among correction coefficients having a characteristic of becoming closer to a value of one as the number of rotations of the engine increases. The control section multiplies the necessary acceleration by the correction coefficient to thereby provide corrected necessary acceleration, and controls rotation of a transporting drive motor in accordance with the corrected necessary acceleration. When the amount of electric power to be generated by a power generator driven by the engine has increased, the control section controls the opening of a throttle valve.

Abstract: A motor control method and apparatus for stopping an object moved by a motor accurately at a predefined target position, shortening the time period required in stop control, in which the motor is driven at a first (high) speed up to a distance from the target position adequate for stop control and then is sequentially braked to a predetermined speed lower than the first speed, driven at a second (low) speed up to a distance from the target position equal to the stopping distance, and braked to a stop. The method and apparatus are used in a time recorder. An impact printing apparatus is also disclosed with printing pin actuation timing correction dependent upon scanning speed or platen shape, striking duration timing dependent upon scanning rate, or printing pin actuation timing dependent upon stored shift amounts.

Abstract: A computer system or other electronic system includes a plurality of cooling fans configured to operate in parallel. The cooling fans are operated in a manner to decrease the operating time of a fan. The cooling fans can alternate in operation. Thus, operating time is more equally divided between the two cooling fans and the hours of operation and number of rotations of the fans is more nearly equal. In an embodiment to reduce noise, two fans run at a lower speed instead of one fan at a higher speed. In an embodiment, a fan operates with a reduced speed which maintains a desired operating temperature. In an embodiment a thermal table is stored in BIOS (basic/input output system).

Abstract: An electric vehicle accessory motor drive power supply system (40) that utilizes a single power supply design to provide efficient variable speed motor control to both brushless and brush-type DC motors (42,44). The power supply system includes at least one of each type of motor along with a first DC-DC converter (46) that provides operating power to the brushless motor (42) and a second DC-DC converter (48) that provides operating power to the brush-type motor (44). Both converters (46,48) have a power input (52) connected to the electric vehicle's high voltage bus (50) and each includes a data input (54) for receiving a speed control signal (SC) indicative of desired motor speed, as well as an output (56) for providing a motor drive signal to its associated DC motor (42,44).

Abstract: A circuit arrangement with a digital controller for operating an electric motor and a method for starting an electric motor are disclosed. Electric motors require a considerably higher current immediately after they have been switched on and during the running-up phase because of the inductance of the motor windings. In order to increase the control sensitivity of the controller for the normal operation, the control range of a digital controller is switched over into a higher current range for the running-up phase. For the normal operation of the motor, the control range of the controller is switched back again into a lower current range. As a result, the control sensitivity of the controller is completely available for the normal operation of the motor.

Abstract: A processor system and method for accurately determining true ground speed in a vehicle having wheel-axles propelled by traction motors is provided. The vehicle is equipped with a radar unit for providing a radar signal indicative of vehicle speed relative to the ground. The radar signal is accurate when averaged over a sufficiently long period of time but may be susceptible to undesirable short term variations. The vehicle is further equipped with speed sensors coupled to the wheel-axles to supply respective wheel-axle speed signals. The respective wheel-axle speed signals may be accurate over a sufficiently short period of time but may also be susceptible to undesirable long term variations.

Abstract: A power drive device is disclosed that includes a motor, a control device coupled to the motor, and a rotatable reference axle member rotatably interlocked with the rotation of the motor. A first detection member detects a first phase and a third phase of rotation of the reference axle member wherein the first phase corresponds to a rotation starting position of the reference axle member and the third phase corresponds to a near completion position of the reference axle member. The device also includes a second detection member that detects a second phase and a fourth phase of rotation of the reference axle member, wherein the fourth phase of rotation corresponds to a rotation completion position of the reference axle member. The control device drives the motor in accordance with the detected phases of the first and second detection members, and in particular, can control the velocity of the motor and the timing of the operation of the motor in relation to a second motor.

Abstract: A pulsing drive system delivers pulsed power signals to the driven wheels of a vehicle for improving the efficiency internal combustion or an electric motor driven vehicles. A controller receives signals such as velocity and demand, and communicates to a means for selectively communicating energy wherein the means for selectively communicating energy converts the pulse signal to a correspondingly conditioned power pulse for powering the vehicle. When combined with a plurality of motors sized with optimal horsepower ranges according to a binary array, an arrangement of such motors provides for an optimally efficient operation of the vehicle by bringing on-line strategically selected combinations of the motors. A control system selectively brings on-line the multiple motors.

Abstract: A combined driving structure is made up of an engine and an electrical machine. The engine is connected to the electrical machine through a clutch which allows the electrical machine to be used as a starting motor for the battery, and when the engine is started, allows the engine to drive a load and also drive the electrical machine to operate as a generator. In addition, the electrical machine can be operated as a motor at low speeds to drive the load by electrical power when the engine is stopped, and as a generator to provide regenerative braking for charging the battery, either with or without friction damping of the engine by the clutch.

Abstract: A pulsing drive system delivers pulsed power signal of the driven wheels of a vehicle for improving the efficiency internal combustion or an electric motor driven vehicles. A controller receives signals such as velocity and demand, and communicates to a means for selectively communicating energy wherein the means for selectively communicating energy converts the pulse signal to a correspondingly conditioned power pulse for powering the vehicle. When combined with a plurality of motors sized with optimal horsepower ranges according to a binary array, an arrangement of such motors provides for an optimally efficient operation of the vehicle by bringing on-line strategically selected combinations of the motors. A control system selectively brings on-line the multiple motors.

Abstract: An electric vehicle control system, according to the present invention, comprises at least two electric motors for independently driving left and right wheels of the vehicle, power supply unit for supplying power to the motors, unit for detecting command entered by a driver of the vehicle and driving operational amount provided for the vehicle, unit for detecting output torques of the two motors, unit for calculating a motor speed difference command signal for making the two output torques consistent with each other, unit for calculating a vehicle speed command signal for the vehicle on the basis of detected command and the driving operational amount, unit for calculating motor speed command signals for respective of the motors on the basis of calculated motor speed difference command signal and the vehicle speed command signal, unit for detecting actual speeds of the two motors, and control unit for voltage controlling supply power from the power supply unit to the motors so that the detected actual speeds o

Abstract: A drive system for a printing machine with a plurality of printing units connected to one another via a gear train into which power is fed at different points by at least two motors, includes supplying each of the motors via a respective controllable, line-commutated converter. A signal is generated by each of the converters that is limited in time between two firing pulses. A current setpoint value is transferred only within a time span in which all of the converters have activated the signal. Coverage of all of the signals which are limited in time is assured in all operating states.

Abstract: The present invention relates to a procedure for selecting the mode of controlling the motor of a crane, or an equivalent lifting apparatus, when at least two alternative modes of controlling the motor are available, and at least one of the modes involves control by means of a switch having at least two positions connectable in a predetermined order, so as to produce corresponding control signals at a control input port. Each control mode uses at least one control signal common to all modes. According to the invention, the control signals applied to a control input port are monitored, the prevailing control situation is determined on the basis of the monitored signals and the mode of control is selected on the basis of which ones of the signals are active and the prevailing control situation.

Abstract: A motion controller, which is adaptable to a variety of different motors, provides motor control signals to the motors of a multi-axis coordinated system as a function of position and velocity commands from a host computer. The motion controller configures the motor control signals to be compatible to the particular motors being driven based upon motor identification instructions from the host computer.

Abstract: An apparatus for selectively controlling a plurality of electric motors for driving individual work objects, the apparatus including an electrical switch which is adapted to produce predetermined speed signals for the electric motor selected, a programmable controller disposed in signal receiving relation relative to the electrical switch and which is adapted to generate a predetermined signalling sequence in response to the signal received from the electrical switch, a variable speed motor drive electrically coupled with the programmable controller, and with the electric motor selected, the variable speed motor drive selectively driving the selected electric motor at a predetermined speed in response to the signalling sequence received from the programmable controller, and a sensor adapted to indicate the work performed by the electric motor whereby the electric switch may be selectively adjusted to control the operation of the electric motor selected.

Abstract: In a machine tool having first and second spindles, which are connected to respective spindle motors and control circuits each control circuit including a velocity controller and a position controller, and which simultaneously grasp the same workpiece, in which state the workpiece is subjected to machining. At such time, a digital velocity command provided by, e.g., a numerical control unit, is supplied to the two spindles simultaneously, switches for isolating the position controller from the velocity controller at each spindle is controlled at the respective spindle, a synchronous operation mode, which changes over the velocity command to a position command, is established, and the digital velocity command value is processed as a position command, whereby the two spindles are subjected to identical positional control. As a result, the rpm's of the spindles are synchronized and the workpiece can be machined and separated into two parts without subjecting it to excessive force.

Abstract: An output circuit having a fail-safe function with: a control signal generating circuit which generates a control signal to control the current of a load and includes an operational amplifier which amplifies a difference between a control value and a feedback value to produce the control signal; a drive circuit which drives a load according to the control signal from the operational amplifier; an output current detecting circuit for detecting a current in a load solenoid and adding an offset current to the detected current, with the output of the output current detecting circuit being fed back to the control voltage generating circuit as the feedback value.

Abstract: A two motor assembly for driving two fan blades to move air through a heat exchanger comprising a first two speed DC motor comprising magnets for establishing a fixed magnetic field, an armature rotor rotatable to drive a first fan blade, a multiplicity of armature coil turns on the armature rotor, a commutator assembly on the armature rotor, and sets of brushes including a tap brush cooperating with the commutator assembly to alternatively operate the two speed DC motor (1) is a first speed mode wherein (A) a system voltage is applied and distributed across all of the multiplicity of armature coil turns to produce a net total back EMF and armature reaction interacting with the magnetic field to cause the armature rotor to rotate in the first speed mode and (B) a tap voltage intermediate the system voltage reduced across a predetermined number of armature coil turns less than all of the multiplicity of armature coil turns is provided through the tap brush and (2) a different second speed mode.