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| Number | Title | Issue Date |
| 7398412 | Measure controlled delay with duty cycle control The disclosed embodiments relate to circuits that produce synchronized output signals. More specifically, there is provided a synchronization circuit adapted to receive an input signal, the synchronization circuit comprising a delay monitor adapted to produce a dela... | 07/08/2008 |
| 7298103 | Control and motor arrangement for use in model train A control and motor arrangement in accordance with the present invention includes a motor configured to generate a locomotive force for propelling the model train. The control and motor arragement further includes a command control interface configured to receive co... | 11/20/2007 |
| 7184654 | Semiconductor device control apparatus and method 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 de... | 02/27/2007 |
| 7171578 | Pulse output function for programmable logic controller with linear frequency change Certain exemplary embodiments provide a method for producing pulsed outputs, comprising: automatically changing a first user-specified pulse frequency to a second pulse frequency; and automatically outputting a plurality of pulses from the programmable logic control... | 01/30/2007 |
| 7141945 | Method and apparatus for controlling motor drive In the invention, a PWM signal is formed at a frequency of a reference pulse signal, the PWM signal which has a pulse width being changed according to a frequency difference between an FG pulse signal for detecting a speed of a brushless motor and the reference puls... | 11/28/2006 |
| 6960894 | Cordless, powered surgical tool A powered tool for performing surgical procedures. The tool includes a handpiece in which a power generating unit is housed. A control member is mounted to the handpiece. The control member is mounted to the handpiece so that the orientation of the control member ca... | 11/01/2005 |
| 6504337 | Motor modeling using harmonic ampere-turn saturation method A method and apparatus are provided for modeling an electric motor. The method includes the steps of interpolating a flux density for each angular position within an air gap of the electric motor from a predetermined air gap and tooth magnetization magnet... | 01/07/2003 |
| 5901269 | Speed regulating circuit for motor of power coping saw A speed regulating circuit for a motor of a power coping saw includes a DC voltage circuit, a manual speed regulating circuit, a feedback controlling circuit and a motor driving circuit. The DC voltage circuit includes a diode, a resistor, a capacitor, an... | 05/04/1999 |
| 5590237 | Apparatus and method for controlling the rotation speed of electric motors The device for controlling the rotation speed of electric motors comprises an adjustable frequency generator (2) generating an output signal (s1) having a frequency which can be adjusted in relation to the desired speed (vd), a pulse... | 12/31/1996 |
| 5463302 | Slip compensation method in a squirrel cage induction motor The invention relates to a method for slip compensation in a squirrel cage induction motor when the motor (2) is fed by an inverter (1) without feedback at a supply frequency less than 20% of the rated supply frequency of the motor after the motor has fir... | 10/31/1995 |
| 4990002 | Motor control circuit A control circuit for maintaining power output of a motor, irrespective of amplitude changes in line voltage. The output of an amplifier is indicative of the line voltage. A ramp generator generates a ramp voltage which is consistent and repetitive, irres... | 02/05/1991 |
| 4845412 | Speed control apparatus for motor In a motor speed controll apparatus for a DC motor, there are provided a frequency signal generating circuit for outputting a signal at a time period corresponding to a rotation speed of a motor, a sawtooth wave output circuit for outputting a sawtooth wa... | 07/04/1989 |
| 4796210 | Method of displaying the speed and distance on board a motor vehicle A method is provided for displaying the speed and the distance on board a motor vehicle. The shaft of an auxiliary motor drives a speed indicator and a mileage recorder and its rotation controls a train of pulses. The speed of rotation of the auxiliary mo... | 01/03/1989 |
| 4785228 | Electrical energy enhancement apparatus A plurality of permanent magnets mounted at equally spaced angular intervals on a drive shaft are rotated past a plurality of electromagnets at equally spaced fixed angular intervals about the axis of the shaft on a plate supported by a frame. An electric... | 11/15/1988 |
| 4752851 | Overload protection for series resistances of electric motors, especially of fans of vehicles driven by electric motors Overload protection for the series resistance of an electric motor in which a voltage drop across the electric motor is monitored. During the occurrence of a reduced voltage drop, for example, as a result of a blocking of the motor or of a fan driven by t... | 06/21/1988 |
| 4673851 | PWM motor operating system with RFI suppression A pulse width modulated DC motor operating system is disclosed which reduces the communication back to the power supply of transient spikes caused by the switching characteristics of the freewheeling diode. The switched current path comprises, in series, ... | 06/16/1987 |
| 4604559 | Apparatus and method for providing useful audio feedback to aid in the operation of remotely controlled powered manipulators The user of a remotely controlled, powered manipulator is provided with audible feedback signals which provide useful information relating to the force and speed of the motor. An audio tone is generated and is frequency modulated by a signal which corresp... | 08/05/1986 |
| 4224558 | Selectable servo ratio and dual speed control system for large centrifuge units A selectable servo ratio and dual speed centrifuge control apparatus utilizing a plurality of phase-lock loops with selected gain increments to provide motor control from coarse to fine in conjunction with an automatic acceleration and deceleration circui... | 09/23/1980 |
| 4087726 | Constant-frequency current choppers for low-rate supply of an inductive load In a constant frequency chopper for low-rate supply for an inductive load, a cut-off capacitor discharge circuit is added which shunts the cut-off capacitor and which, when the motor is required to operate at a low rate, helps to bypass the excess energy ... | 05/02/1978 |
| 4048549 | Circuit for eliminating current noises from d.c. motor A circuit for eliminating a.c. noise current which is produced as a result of the interruption of electrical contact between a brush and a commutator of a d.c. motor and comprises a capacitor which applies the noise current to a transistor, which in turn ... | 09/13/1977 |
| 4029192 | Digital circuit for controlling the return speed of a business machine carriage A digital electrical circuit for selectively activating a clutch mechanism for controlling the return speed of a business machine carriage. A carriage speed pulse transducer provides a series of sync pulses with intervals between each sync pulse being a f... | 06/14/1977 |
| 3958182 | Electronic circuit for supplying energizing pulses of predetermined duration to an electric motor An electronic circuit for supplying energizing pulses of predetermined duion to an electric motor comprises a principal chain of frequency dividing elements, a bistable multivibrator, and an auxiliary divider circuit comprising a secondary chain of serie... | 05/18/1976 |
| 3937001 | Watch movement driven by a spring and regulated by an electronic circuit An electronically regulated watch movement comprising a time-wheel mechanism driven by a drive, a generator being coupled to the drive via at least a portion of the time-wheel mechanism and with substantial gear reduction. The generator includes a rotor w... | 02/10/1976 |
