Did You Know...
...that the first rickshaw was invented in 1869 by an American Baptist minister, the Rev. E. Jonathan Scobie, to transport his invalid wife around the streets of Yokohama?
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| Number | Title | Issue Date |
| 6850023 | Method of measuring motor speed A speed sensor for an electric motor detects the variation in the electric field of the armature due to commutation to produce an output signal indicative of the speed of rotation of the motor. ... | 02/01/2005 |
| 6806669 | Motor overload coil control A motor overload coil control is disclosed for use in a motor starter/relay contactor. The control includes an 8-bit, 8-pin microcontroller that together with an I/O reduction circuit, is capable of functioning 13 I/O's with only 5 I/O pins on the microcontroller. T... | 10/19/2004 |
| 6188187 | Apparatus and method of regulating the speed of a DC brushless motor A control circuit for regulating the rotational speed of a DC brushless motor includes an electrical conduction switch having an input, an output and a control terminal for passing a motor supply signal to a DC brushless motor. A voltage averaging circuit... | 02/13/2001 |
| 6154001 | Anti-glitch circuit for voice-coil-motor servo operation in disk drive systems A circuit to pull down a driver circuit of a motor, including a circuit to monitor the input signal to a driver amplifier to compare the input signal with the output signal from the motor and to output a difference signal when the input signal and the out... | 11/28/2000 |
| 6011902 | Motor control circuit In an optical disc player, as signals are read from and written to an optical disc, the optical disc is rotated by a spindle motor and an optical pickup is moved by a sled motor. These motors are both direct-current motors. The motor control circuit of th... | 01/04/2000 |
| 5892347 | Tape drive with high performance gain amplifier using radio frequency dielectric heating A power amplifier (18) for driving a brushless DC motor (22) includes a processor (40) which receives a signal indicative of motor situational usage and generates a mode state signal indicative of which one of a plurality of amplification modes is to be i... | 04/06/1999 |
| 5818179 | Brushless motor drive circuit including a linear amplifier for sending an output signal based upon the detected back electromotive force voltage In a d.c. brushless motor drive circuit, the output amplifier produces a motor winding drive current with dulled rise/fall edges from a detected sinusoidal back e.m.f. voltage induced on the winding during the steady-state operation when the motor runs at... | 10/06/1998 |
| 5640073 | Brushless dc motor unit and method of driving the unit A brushless dc motor unit has 3-phase armature windings, a permanent-magnet rotor, a dc power supply having a motor drive voltage and a midpoint voltage that is one half of the motor drive voltage, and an electronic commutation circuit. Back emf voltages ... | 06/17/1997 |
| 5625264 | System for controlling a brushless DC motor A system for controlling a brushless DC motor which can minimize a torque ripple of a motor, thus reducing minute vibrations of the motor and loading devices and increasing efficiency. The system includes a current command generator for producing a curren... | 04/29/1997 |
| 5600219 | Sensorless closed-loop actuator unlatch A first method for detecting movement of an actuator includes supplying a demand current to a voice coil motor of the actuator (A1), sampling a voice coil motor voltage (B1), performing a slope detection of a voice coil motor voltage... | 02/04/1997 |
| 5473725 | Method and device for controlling the speed of the brushless DC motor provided for an electric vehicle The speed of a brushless DC motor driving an electric vehicle is controlled with a speed feedback signal proportional to rotation speed of the motor by processing the back electromotive force (EMF) waves of the brushless DC motor. In this method, the back... | 12/05/1995 |
| 5414792 | Electric throttle and motor control circuitry A solid state, electric motor control circuit is provided in conjunction with a solid state throttle and vehicle sensor circuit that together incorporate; a Hall Effect throttle position sensor circuit, a throttle position signal amplifier circuit, a vehi... | 05/09/1995 |
| 5404418 | Closed-loop feedback control system having an adaptive filter A closed-loop feedback control system is disclosed for controlling an operation of a load. An actual operation signal is subtracted from a reference operation signal to produce a resultant signal which is used to control the operation of the load. A filte... | 04/04/1995 |
| 5397967 | Slew rate circuit for high side driver for a polyphase DC motor A high side driver circuit and method for controlling the turnoff slew rate to an inductor of a motor is presented. The inductor is selectively connected between a supply voltage on a high side and a reference potential on a low side. The driver circuit h... | 03/14/1995 |
| 5367600 | Motor control for a treadmill having improved power supply and improved speed regulation under intermittent loading A motor control for a treadmill has an improved, inexpensive, and simple set of power supplies, derived from the bus voltages of the DC busses with simple voltage dividers, to supply operational amplifiers connected to the positive DC voltage bus with a d... | 11/22/1994 |
| 5364026 | Ventilation fan control The residential structure ventilating apparatus disclosed herein employs a variable speed exhaust fan. The speed is responsive to a sensor which detects air temperature at the exhaust port. The fan is energized when the sensed air temperature rises above ... | 11/15/1994 |
| 5351336 | Motor control having improved speed regulation under intermittent loading A control for energizing a DC motor to provide improved speed regulation to the motor under transient conditions. The control includes a regulating circuit having an output signal controlling the armature voltage applied to the motor. An input speed refer... | 09/27/1994 |
| 5317669 | Direct current motor speed control apparatus The present invention is a two unit electronic control system to reduce power demands imposed upon direct current power sources. The present invention comprises a contact/resistor network, a trigger generator, a pulse generator, a waveform stabilization c... | 05/31/1994 |
| 5299277 | Flexible disk drive device A flexible disk drive device includes an adjusting circuit which sets termination timing of outputting of an index signal in response to the rotating speed of a motor by adjusting charge or discharge time constant of a capacitor; a reference voltage gener... | 03/29/1994 |
| 5267344 | Direct current power control circuit for use in conjunction with regulated input signal A solid state DC power control circuit to efficiently use DC battery power without the normally associated energy waste which includes an input control signal, amplifying and conditioning circuit (133), a triangular waveform generator circuit (131), a com... | 11/30/1993 |
| 5230035 | Motor speed controller A motor speed controller, for example for accurate linear control of DC motors, includes an error amplifier, such as an integrating error amplifier, for providing a variable controlled voltage to a motor in response to an input to the amplifier, the input... | 07/20/1993 |
| 5201023 | Variable speed latching motor control A solid state electronic motor power control circuit for portable paint pumps having a MOSFET power control device and an operational amplifier connected to the MOSFET to selectively operate as a switch driver in a first state and as a linear gain amplifi... | 04/06/1993 |
| 5179621 | Direct current power control circuit A solid state DC power control circuit to efficiently use DC battery power without the normally associated energy waste which includes an input control signal filtering, amplifying, and conditioning circuit (133), a triangular waveform generator circuit (... | 01/12/1993 |
| 5123081 | Temperature control system for motors and power components of a material handling vehicle The present invention features a system and method for preventing overheating of a motor and/or power amplifier of a material handling vehicle by controlling the performance of the vehicle as a function of motor and/or power amplifier temperature. Tempera... | 06/16/1992 |
| 5086492 | Switching current regulator for motor control An improved motor control circuit is disclosed in which energy stored in the motor is transferred back to the power supply rather than being passively dissipated. The sense of a feedback signal is reversed at a summation node by combining the signal with ... | 02/04/1992 |
| 5046123 | Error signal detection circuit in a servo control device An error signal detection circuit in a servo control device comprises a reference signal generation circuit for selectively generating reference signals of different periods, each having a slope which changes from a reference value at a substantially cons... | 09/03/1991 |
| 5029229 | Direct current power control circuit A solid state DC power control circuit to efficiently use DC battery power without the normally associated energy waste which includes an input control signal filtering, amplifying, and conditioning circuit, a triangular waveform generator circuit, a comp... | 07/02/1991 |
| 5010582 | Pickup driving device for disk player A pickup driving device for a disk player is provided, wherein the gain of a negative feedback circuit for driving a slider motor is made variable and the gain is changed correspondingly to the operation mode of a disk player, which made it possible to in... | 04/23/1991 |
| 5003628 | Variable speed D.C. motor control A manually operated switch lever moves arm 105 along resistor 113 to generate a "raw" motor speed demand signal which is amplified and inverted by amplifiers 115 and 119 to form a "base line" demand signal. The "raw" demand signal and a motor load signal at th... | 03/26/1991 |
| 4901366 | Circuit arrangement for the timed control of semiconductor switches In a circuit arrangement for the timed control of semiconductor switches (1-4) to each of which a freerunning diode (D1-D4) is connected in parallel and which are arranged in branches of a bridge, an ohmic-inductive load (5) of low loss power which lies i... | 02/13/1990 |
| 4862048 | Speed control system In a speed control system for a carriage movable along a predetermined path, light beams originating at the ends of the path are deflected by light conductors aboard the carriage so that they are interrupted, as the carriage moves, by a slotted plate exte... | 08/29/1989 |
| 4859918 | Method and apparatus for producing a speed control voltage for direct current motors in typewriters or similar office machines A method and means for producing a control voltage for controlling a direct current motor makes use of a tachometer voltage providing two ninety degree phase shifted tachometer signals. From these are derived four coding signals comprising the tachometer ... | 08/22/1989 |
| 4851743 | DC motor speed controller having protection A controller for a battery-driven DC motor controls the average motor current by switching a series-connected FET on and off with a pulse-width-modulated gate signal. Motor speed is changed by changing the duty cycle of the signal, which is generated by a... | 07/25/1989 |
| 4851744 | Feedback circuitry for D.C. motor speed control A circuit for controlling the speed of a DC motor provides delay and sampling means in the feedback loop to delay the triggering of the SCRs driving the DC motor and measured the motor armature voltage during the period of the delay, thereby eliminating e... | 07/25/1989 |
| 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 |
| 4842190 | Control circuit for a forced-air heating system A control circuit for a forced-air heating system comprises a silicon diode that is positionable in thermally-conductive relationship with the interior space of a furnace plenum. A current source supplies current to the silicon diode, and the potential dr... | 06/27/1989 |
| 4843288 | Phase locked motor control system for multiple disk drive units A motor control system and related method are provided for phase and frequency locked operation of multiple spindle motors in a computer disk drive environment or the like, for coupling two or more disk drive units together to provide expanded data storag... | 06/27/1989 |
| 4839570 | Current limiting control circuit for d.c. motors A current limiting control circuit for a d.c. motor, wherein compensation is provided for the inherent voltage drop across the armature of the d.c. motor with a first dedicated amplifier, while a second dedicated amplifier provides current limit control. ... | 06/13/1989 |
| 4837486 | DC motor speed stabilizing method and apparatus The speed of a DC motor is stabilized to correspond to a reference speed by a motor driving control that is instantaneously responsive to the interval between reference pulses corresponding to the reference speed and actual observed pulses corresponding t... | 06/06/1989 |
| 4833375 | Digital motor control system A digital motor control system includes a flip-flop latch for receiving motor circuit drive data from a microprocessor, a counter for counting to a predetermined value representing the total duration of a motor drive pulse, a comparator for comparing the ... | 05/23/1989 |
