Matches 1 - 50 out of 175 1 2 3 4 >
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7551411 Control and protection methodologies for a motor control module  
A motor control module designed to control operation of a plurality of different motors in a plurality of different tools a power tool uses an electronic clutch in the module in conjunction with a...
7545110 Motor drive control  
A drive system for a multi-phase brushless motor comprises a single current sensor drive circuit, including switch means, switchable between a plurality of states. A controller is arranged to...
7456597 Method of driving fan motor  
A fan motor is driven under a pulse width modulation (PWM) control. PWM signals to be supplied to a circuit for driving the fan motor are formed from carrier waves having a specified frequency and...
7359628 Control device for an electric motor  
The invention relates to a drive device for an electric motor, in particular for a brushless DC motor in an electrical tool, which is powered by a rechargeable battery. The drive device has at...
7308192 Motor drive control with a single current sensor using space vector technique  
A drive system for a three phase brushless AC motor that is operative to optimize a transistor switching pattern to improve power output while allowing current measurement in all of the phases...
7260319 Abnormality monitoring device for motor control system  
An abnormality monitoring device monitors a PWM driving signal output from a driving section of an associated motor control system to judge whether the driving section is operating abnormally. By...
7245106 Controller of pulse width modulation signal-driven device, and method of reducing noise of the device  
A controller of a pulse width modulation signal-driven device, includes: an instruction input of operating the pulse width modulation signal-driven device; a control section generating a control...
7231139 Digital noise reduction for motors  
A system and method for reducing fan noise by controlling the drive current to the fan motor. In one embodiment the system approximates a linear drive using a number of transistors in parallel and...
7193377 System and method for controlling motor speed using a biased pulse width modulated drive signal  
A motor drive circuit includes a switching circuit having an input node that receives a drive signal and a control node that receives a control signal. The switching circuit couples the input node...
7158865 Current driver employing pulse-width modulation  
A current driver capable of generating a controlled current in the form of a pulse-width modulation (PWM) signal suitable for controlling an electronic device such as a solenoid is disclosed. The...
7092623 Method and apparatus to achieve accurate fan tachometer with programmable look-up table  
A system and method for measuring the speed of a fan is presented. The duty cycle of a pulse width modulated (PWM) power signal may control speed of the fan. The fan may generate tachometer pulses...
6982531 Driving circuit for switches of direct current fan motor  
A driving circuit for switches of direct current fan motor is disclosed. The driving circuit includes a plurality of switches, a first control circuit, and a second circuit. The switches are driven...
6836614 Electrical power tool having a motor control circuit for providing control over the torque output of the power tool  
A power tool such as an electric drill typically contains a gear train that couples the output spindle of the motor to the tool bit-receiving chuck. The control circuit for the power tool is...
6810202 Apparatus for controlling rotational speed of motor  
An apparatus for controlling a rotational speed of a motor, coupled to a sensing unit capable of outputting a sensing signal. The apparatus includes a controlling unit, coupled to the sensing unit,...
6775469 Method of controlling an electronically commutatable motor  
An electronically commutatable motor having field windings activatable in sequence with a commutation frequency via semiconductor output stages using control signals connectable and disconnectable...
6700339 Circuit for regulating a power supply voltage  
Disclosed is a circuit for regulating a power supply. In one embodiment, the circuit includes a signal generator for generating a square wave signal that varies in magnitude between a first voltage...
6680596 Electric motor having regenerative braking  
An electric motor having a regenerative braking capability is described which has several embodiments, each of which utilize two pairs of brushes, each pair of which has individual brushes...
6671459 DC motor control method and apparatus  
A method for maintaining a target speed of a DC motor includes the steps of obtaining a feedback signal from the motor corresponding to motor speed, measuring an actual time for a predetermined...
6650074 Fan speed controller with conditioned tachometer signal  
The speed of a fan motor is controlled by varying a DC voltage to the fan motor. A series pass transistor is used to vary the DC voltage to the fan motor. A power management controller sets the fan...
6617818 Voltage independent PWM base frequency generating method  
A DC brushless motor operation speed control method is disclosed. First, a linearly voltage dependent current source is used to charge a capacitor and the terminal voltage of the capacitor is...
6580235 Electric motor with two modes of power supply switching  
An electronically switched motor includes a stator-rotor assembly fitted with three-phase driving windings, a series of switches for powering the windings, and a control circuit suitable for...
6534948 Motor driving circuit, a method for driving a motor, and a semiconductor integrated circuit device  
A motor driving system is disclosed. The circuit includes a power converter for supplying a brushless motor having a permanent magnetic rotor with pulse-width modulation controlled driving power, a...
6424113 Method and apparatus for pulse width modulation  
A pulse width modulation circuit ( 10 ) for a motor controller is operated by generating an offset voltage and adding the offset voltage to a carrier timing signal to form an offset carrier timing...
6385395 Fan motor with its speed controlled by operating periods of a pulse wave  
A fan motor whose speed is controlled by an operating period of pulse waves includes first and second rectifying circuits, a voltage comparison circuit, and a differential amplifier. A pulse wave...
6327424 Method of and circuit for operating a motor using power transistors  
The pulse duration of voltage pulses for the control of a motor winding through power transistors is effected by writing data from a microprocessor or CPU to a module having intermediate register...
6326760 Method and device for controlling a synchronous motor with permanent magnet  
A method and device for controlling a synchronous permanent magnet motor with at least one phase, a coil and a rotor, wherein the method and device controls the powering of each motor phase,...
6321032 Brushless repulsion motor  
A brushless repulsion motor which includes a stator and rotor rotatably mounted on the stator is provided. The stator and rotor are contained within a first housing, the stator having at least one...
6091887 Method and apparatus for controlling a physical parameter  
The invention relates to a method for adjusting a real value (actual value) of a physical quantity to a preset value (target value) with the following steps: (a) the difference between the...
6055359 DC motor drive control with improved current sensing  
A PWM DC motor control circuit having improved current sensing. A power switching device controls the DC motor in a common drain connection, whereby armature current sensing is achieved at the...
6002225 Method for the control of a motor  
A method of breaking a motor includes the step of applying a pulse width modulated signal to the winding of the motor. A switching voltage is used to intermittently reverse the poles of the motor...
5986426 Adaptive pulse width modulated motor control  
A motor control method and apparatus for spindle motor control and for voice coil motor (VCM) control in a direct access storage device (DASD). Characteristics of the pulse width modulation (PWM)...
5933573 Method of controlling an electric motor and apparatus for carrying out the method  
An electric motor (12) is supplied with current (i mot ) via a semiconductor switch (14). During operation, the semiconductor switch (14) is driven by a Pulse Width Modulation (PWM) unit 15 using a...
5859511 Motor with input-controlled high side driver  
A circuit for operating a polyphase DC motor, such as the type having a plurality of "Y" connected stator coils, has circuitry for charging the coils at a rate which will reduce EMI and other...
5802248 Multi-speed motor  
Control circuitry for a multi-speed, rotational, direct current motor can include a means to select one of a plurality of discrete circuits to select a desired speed of the motor, each circuit...
5798573 Split power supply  
A power supply circuit for a control circuit of a motor having an armature, includes a first power supply branch having a series combination of a first resistor, a first diode and a Zener diode...
5787376 Power steering motor control unit with driving mode correction  
A power steering motor control unit for driving a motor in a PWM mode with feedback motor current control reduces fluctuations in the output torque of the motor caused by switching among a...
5721474 Method and apparatus for preventing excessive current flow in a motor  
A motor control circuit comprises a current command circuit generates a current command signal proportional to a selected motor speed. A comparator generates a comparator output signal proportional...
5574344 Power steering apparatus for performing feedback control of motor-driving current  
A power steering apparatus for use in association with an electric motor, includes a switch circuit driven by a PWM wave signal which switches between one polarity and the other of the voltage...
5309077 Apparatus and method for loading a cassette tape in a video equipment  
An apparatus and a method for loading a cassette tape in a video equipment, in which driving of a DC motor can be controlled according to an amount of load which is applied to the DC motor when the...
5296787 Method for regulating a motor current of a brushless D.C. motor  
A method for regulating a motor current in phase windings of a brushless d.c. motor, wherein current is applied to the phase windings individually via an electronically controllable, d.c.-voltage...
5291109 Windshield wiper system  
A windshield wiper system (10) which includes an electrical drive motor (12) that makes available a driving moment for at least one windshield wiper (16) performing a back and forth movement on a...
5260634 Constant current driving system for a stepper motor in rotating disk  
In order to drive the stepper motor of a floppy disk drive with practically constant current in the face of fluctuations in supply voltage fed from a host system, a power control pulse generator...
5220634 Control circuit for a DC motor  
A DC power supply for a DC motor is controlled by a drive transistor. An "ON" state of the drive transistor is maintained by a comparator which compares a terminal voltage at a point between the DC...
5126642 Variable speed motor control  
A motor control for a multi-phase compressor motor. The control responds to a speed control signal to cause the motor speed to track the speed control signal without changing the motor torque. This...
5077824 Direct-current motor control  
A motor control circuit for controlling supply of electric power from a power source to an electric motor, in particular for use in electric power tools, comprising: an output power device for...
5077823 Electric motor starting circuit  
The invention provides a cushioning control circuit which restricts the initial flow of current to a D.C. permanent magnet motor by providing a neon control lamp in series with a pair of triac...
5017854 Variable duty cycle pulse width modulated motor control system  
A control system for controlling a direct current powered motor in which the direct current voltage, which may not be constant, is reversibly commutated across the coil or winding of the motor...
4980620 Current-free synthesis of parameter-free zero-impedance converter  
A method of synthesizing a system which forces finite value of an impedance to zero comprising a positive voltage feedback of a prescribed amount of voltage feed back and a negative voltage...
4963810 Variable load motor drive control  
The invention relates to a method and apparatus for making low inertia motors useful under circumstances where the load exerting drag on the motor during start-up acceleration may be different from...
4905300 Motor control and power systems and methods of operation thereof  
A pulsating D.C. voltage is developed by a rectifier 86 and is filtered by a capacitor 100 to facilitate application of a relatively smooth, enhanced D.C. voltage to a motor 106. The charged...
Matches 1 - 50 out of 175 1 2 3 4 >