Abstract: A surgical device includes a housing, a drive shaft, a motor, a control button, and a motor speed controller. The motor is configured to rotate the drive shaft that is disposed within housing. The control button is disposed on the housing and the motor speed controller is operably associated with the control button. The motor speed controller varies an angular velocity of the motor as a function of a percent of actuation of the control button between an unactuated position and a fully actuated position.

Abstract: A load torque estimation apparatus includes an acquisition unit configured to acquire a smoothed signal, the smoothed signal being obtained by smoothing a signal indicating a composite current of electric currents flowing in respective phases of an electric motor; and an estimation unit configured to estimate load torque of the electric motor based on the smoothed signal and a rotational speed of the electric motor.

Abstract: A power tool comprises a housing, a direct current motor arranged in the housing, a speed reduction mechanism coupled to a shaft of the motor, a tool head driven by the speed reduction mechanism, a first direct current power source, and a switching device. The motor comprises a common brush, a high speed brush and a low speed brush which are in sliding contact with a commutator. The switching device is configured to selectively connect the common brush and the high speed brush with the power source to operate the motor in a high speed mode and to connect the common brush and the low speed brush with the power source to operate the motor in a low speed mode.

Abstract: A fan control system includes a controller that is coupled to a plurality of fan couplers. A computer-readable medium is coupled to the controller and includes a first fan identification corresponding to a first fan, a second fan identification corresponding to a second fan, and at least one fan property associated with each of the first fan identification and the second fan identification. The controller is operable to monitor at least one operating parameter of each of the first fan and the second fan when the first fan and the second fan are coupled to a respective fan coupler. The controller is further operable to use the at least one fan property associated with each of the first fan identification and the second fan identification and the at least one operating parameter of each of the first fan and the second fan in order to adjust a speed of the second fan relative to a speed of the first fan.

Abstract: A circuit for varying the speed of a variable speed motor having a power source to provide a voltage to the motor and a diode as a means to provide a voltage drop within the circuit that is substantially independent of the amount of current to the motor. The invention may further comprise an electric toothbrush using the circuit.

Abstract: Electrically powered devices are provided that are generally capable of automatically adjusting an operating speed of a tool removably connected to the device. The device includes circuitry that evaluates tool wear for the tool removably connected to the device, produces a tool wear speed related signal, and adjusts the operating speed of the tool based on the speed related signal. The device may further be capable of automatically setting the initial operating speed of the particular tool removably connected to the device by identifying the particular tool and setting the initial operating speed which may later be adjusted.

Abstract: A fan control device receives a reference revolution signal to control the rotation speed of a fan. The fan control device includes a reference signal generating module, a revolution modifying module and a fan driving module. The reference signal generating module generates a first reference signal and a second reference signal. The revolution modifying module receives the first reference signal and the second reference signal, and generates a target revolution signal according to the reference revolution signal and the first and second reference signals. The fan driving module receives the target revolution signal and generates a driving signal to drive the fan according to the target revolution signal.

Abstract: A drive unit, in particular for a fan in motor vehicles, is indicated, comprising an electric motor (12) operated on a DC line (UBat), and comprising a device (13) for controlling the speed of the motor (12) by changing the operating voltage applied at the motor (12). In order to cost-effectively realize a stepwise adjustment of the motor speed, the speed control device (13) comprises a plurality of resistors (R1-R3) and a plurality of semiconductor switches (T1-T3) for selectively connecting the motor (12) in series with at least one of the resistors (R1-R3) (FIG. 1).

Abstract: The present invention provides a multistage rotating speed control circuit which is connected to a positive DC supply voltage and controls the rotating speed of the DC motor. The multistage rotating speed control circuit comprises a digital control circuit and a driving circuit. Besides, it comprises an input voltage modifying circuit which delivers an input voltage; a reference voltage generating circuit which provides a fixed number of reference voltage; and a comparing circuit consisting of the fixed number of comparators, each of which receiving the aforementioned input voltage at its positive end and a different reference voltage generated by the reference voltage generating circuit at its negative end, delivering an output digital signal based on the comparison result of the two input signals, these output digital signals collectively making up an input digital signal set for the digital control circuit.

Abstract: An electric motor vehicle comprises as a drive system a battery, a motor, and a controller for controlling the rotation of the motor. The electric motor vehicle disposes an accelerator for controlling speed of the motor, a key switch for turning on or off the motor and the controller, a circuit for judging an opening/closing state of the accelerator when the key switch is turned on, and a circuit for preventing the rotation of the motor when the key switch is turned on with the accelerator open.

Abstract: An arrangement is disclosed for controlling fan motors in fan-powered terminal units which permit the air flow of the terminal units to be factory preset and reset using a voltmeter. The fan motor is responsive to the pulse width of pulses of a pulse width modulated signal to provide an air flow which is proportional to the pulse width. By adjusting the pulse width, the air flow may be set as desired. A pulse width modulated signal having pulses with a set amplitude and frequency is generated. The dc voltage of the pulse width modulated signal is measured using a voltmeter. As the pulses have a set amplitude and frequency, the pulse width of the pulses may be adjusted by controlling the dc voltage of the pulse width modulated signal. The fan motor is programmed to deliver the set air flow over a range of static pressures.

Abstract: A cooling system for cooling components of a computer is provided. The cooling system includes a DC fan which operates at a speed which is substantially proportional to the voltage that is applied to the fan. A zener diode voltage divider is connected in series between a voltage source and a first input of the fan. The second input of the fan is connected to a reference voltage source. A switch is also connected in series between the voltage source and the first voltage input of the fan so as to be connected in parallel with the zener diode voltage divider. When the switch is in a first position, the voltage produced by the voltage source is applied directly to the fan allowing the fan to operate at a first speed. When the switch is in a second position, the voltage from the voltage source is applied to the first input of the fan through the zener diode such that the first input of the fan receives a second voltage that is less than the first voltage thereby causing the fan to operate at a second speed.

Abstract: A method and apparatus automatically associate a sensed mechanical parameter to a range of motor velocity for controlling the rotational velocity of a motor driving a medical instrument. The method and apparatus sense or measure the mechanical parameter whose value, controlled by a human operator, through for example, a footpad, can be measured and converted to a digital signal. The method and apparatus, in response to the measured sensed mechanical parameter, automatically scale the range of parameter values to a new range of motor velocity values thereby adjusting, to the mechanical displacement (force or distance) with which the user is most comfortable. The transformation also provides deadband values around the minimum and maximum motor velocities so that maximum motor velocity is not "chased" and minimum motor velocity is not sensitive to small perturbations due to thermal effects and other events which may affect the mechanical sensor output.

Abstract: A DC motor control system reduces power demands imposed upon a DC power source energizing a utilizing device by varying the time during which power application occurs, but not the magnitude of the power which remains constant. The DC motor control system includes a transducer/resistor network, a trigger pulse circuit, a control signal circuit, a driver circuit, and a switch network. The control signal circuit outputs a duty cycle control signal as regulated by the transducer/resistor network and the trigger pulse circuit. The transducer/resistor network permits an operator to determine the duration of the duty cycle control signal, which varies from 0% to 100%, while the trigger pulse circuit establishes the frequency of the duty cycle control signal. The driver circuit receives and amplifies each duty cycle control signal outputted by the control signal circuit. The driver circuit inputs each amplified duty cycle control signal into the switch network to activate it.

Abstract: An electrical implement having a bypass mechanism for controlling a variable speed motor is disclosed. The implement includes a tool, a variable speed electrical motor activatable for driving the tool, a housing supporting the motor and tool, and a control knob for controlling the speed of the motor. The control mechanism includes an on/off switch and a variable speed control circuit. The variable speed control circuit includes a variable resistance rheostat and bypass switch. The control knob controls whether the bypass switch causes current to bypass the rheostat to operate the motor at a predetermined speed or else whether the resistance in the rheostat is variable to change the speed of the motor. The control mechanism includes a cantilevered beam engageable by the control knob to operate the bypass switch. The cantilevered beam is sufficiently flexible to allow for large deflections while placing only limited force across the bypass switch.

Abstract: A system, which may be a cooling system for a motor vehicle engine, has two direct current motors together with switching circuits which provide selective connection of the windings of the two motors to a direct current voltage source in such a way as to obtain different operating modes for each motor. One of the motors has four brushes, the first of which is permanently connected to the first polarity of the source, while its second, third and fourth brushes are arranged so that they can be connected to the appropriate source polarities respectively through either three interruptors or two. The second motor has two brushes permanently connected, respectively, to the same first source polarity and to the third or fourth brush of the first motor.

Abstract: A MOSFET control topology and a physical structure for a motor control which provide a more efficient and economic DC motor control are disclosed. The control topology introduces a synchronous-rectification technique wherein free-wheel diodes are replaced with MOSFET devices that are switched on and off by a logic circuit so that they are conductive for commuting motor current during periods that the motor current supply is switched off. The physical structure and method of assembling a DC motor control eliminate time consuming assembly techniques while ensuring effective waste heat exchange between electronic components and a heat sink of the control by providing quick-install spring retainers for urging the components into heat sink conducting contact with the heat sink. The physical structure also provides for high density packing of electronic components in a controller.

Abstract: A fan speed control adjusts the speed of an electric fan motor without producing audible noise at frequencies above about 60 Hz. A linear slide switch is positionable in each of four discrete positions to connect various capacitances in series with the motor to limit the power provided to the motor from an ac source. An actuator engaging the slide switch includes detents to urge the switch into each of the four positions. The urging force is a maximum approximately half-way between adjacent positions and decreases linearly to a minimum at each position. The maximum force necessary to move the switch from one position to the next is not greater than about 0.8 lb., to avoid overshoot when the actuator is operated by an extended arm.

Abstract: A method of controlling a drive unit of a pile-lifting device located at a sheet-fed printing machine includes starting-up the drive unit with a first mode of operation selected by an electronic current wherein rated torque is high and rated speed is low for respectively lifting and lowering the pile and, after a given period of time, following the starting-up of the drive unit, switching to a second mode of operation of the drive unit wherein the rated torque is low and the rated speed is high if the speed has exceeded a preset value during a lifting of the pile, and has not exceeded a preset value during a lowering of the pile; and a device for performing the method.

Abstract: A dc motor wherein a driving force thereof can be used effectively with a simple and compact mechanical construction and a motor controlling system which can control such a dc motor to be driven efficiently. The motor comprises at least two coils, and change-over means for changing electric connection of the coils to change over the motor, when power is selectively supplied to the coils, between a first mode in which the torque produced is relatively high and the rotational frequency is relatively low and a second mode in which the torque is relatively low and the rotational frequency is relatively high. The motor controlling system includes selecting means for automatically selecting one of the first and second modes to control the change-over means is response to a given condition of the motor.

Abstract: A motor control apparatus for a sewing machine includes an adjustable speed setter for generating a speed set signal. A first memory stores a plurality of reference values each defining a reference region into which the speed set signal can fall. A second memory stores speed setpoint values corresponding to the reference regions. A central processing unit selects one of the reference regions by comparing the speed set signal with the reference values and selects the corresponding speed setpoint value from the second memory. A motor is controlled to run at the selected speed setpoint value.

Abstract: An electric food mixer includes a membrane potentiometer control which is responsive to a user's touch to select the speed of the mixer's motor. The top surface of the membrane potentiometer control is flexible and forms a continuous strip which is mounted flush with the mixer motor's housing so as to facilitate cleaning and improve the appearance of the mixer. The top surface of the membrane potentiometer control may include a flexible liquid crystal display to provide to the user visual feedback of the selected motor speed. A digital control is responsive to the output of the membrane potentiometer control for operating the mixer's motor at a mixer motor speed selected in accordance with the membrane potentiometer's output from a large number of selectable mixer motor speeds stored in a look up table in the digital control.

Abstract: An arrangement is disclosed for controlling fan motors in fan-powered terminal units which permit the air flow of the terminal units to be factory preset and reset using a voltmeter. The fan motor is responsive to the pulse width of pulses of a pulse width modulated signal to provide an air flow which is proportional to the pulse width. By adjusting the pulse width, the air flow may be set as desired. A pulse width modulated signal having pulses with a set amplitude and frequency is generated. The dc voltage of the pulse width modulated signal is measured using a voltmeter. As the pulses have a set amplitude and frequency, the pulse width of the pulses may be adjusted by controlling the dc voltage of the pulse width modulated signal. The fan motor is programmed to deliver the set air flow over a range of static pressures.