Did You Know...
...that a workman who left the soap mixing machine on too long was responsible for making Ivory Soap? He was so embarrassed by his mistake that he threw the mess in a stream. Imagine his dismay when the evidence of his error floated to the surface! Result: Ivory soap, the soap that floats.
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| Number | Title | Issue Date |
| 7447423 | Fan speed control device and method detailed description of the invention A fan speed control device includes a controller, a switch and a voltage regulator. The controller detects a rotation speed signal of the fan to generate a first driving signal when the rotation speed signal is relatively higher than a predetermined rotation speed s... | 11/04/2008 |
| 7323842 | Rotating electrical machine A rotating electrical machine has a housing with a shaft mounted rotatably in it. A rotor is fixed to the shaft and has a plurality of magnetic poles. A stator is positioned about the rotor and has a winding. A switch is mounted within the housing and has a first po... | 01/29/2008 |
| 7215091 | Method for controlling a DC printer motor with a motor driver A method of the invention is for controlling a DC printer motor with a motor driver during a potential stall of the DC printer motor. One step of the method includes detecting the start of the potential stall of the DC printer motor. Another step includes thereafter... | 05/08/2007 |
| 7185528 | Speed and fluid flow controller A system and method for measuring fluid flow rate in a system where fluid is pumped, such as a gas monitoring instrument where gas is pumped from a space such as a room or enclosure through a conduit to a sensor. The flow of gas through a pump is determined by measu... | 03/06/2007 |
| 7166980 | Methods and apparatus for monitoring a brushed permanent magnet motor using back-emf measurements Techniques sense a back-emf voltage from a brushed permanent magnet motor. Such techniques can be used for a variety of purposes, such as to estimate the current that is being applied to the motor, to estimate the motor's velocity, position, torque, and the like. On... | 01/23/2007 |
| 7129610 | Commutator for an electric motor A commutator includes a support ring and a plurality of conducting segments arranged over a circumference of the support ring. Some of the conducting segments have an electrically insulating portion. The commutator is employed with a device that measures rotation of... | 10/31/2006 |
| 7123821 | DC motor A DC motor includes a power source, a stator and a rotor. Permanent magnets are mounted to either the stator or the rotor. Electromagnets are mounted to the other of either the stator or the rotor. Each electromagnet includes two coils which are each branched with a... | 10/17/2006 |
| 7114933 | Electrically driven potter's wheel A potter's wheel for working clay and other pottery material on a turntable driven by a DC brushless motor. In order that driving speed is not affected by the load due to user's access to the work of clay, the speed of the motor detected by a speed detector is fed b... | 10/03/2006 |
| 7111983 | Temperature detection method and apparatus for inverter-driven machines A resistance temperature detector device and system are provided for measuring the temperature adjacent to windings within a stator assembly. The resistance temperature detector comprises a resistive element enclosed within a plurality of insulative layers, includin... | 09/26/2006 |
| 7106028 | Controller of A.C. generator for vehicles The structure of the present invention includes: a switching element inserted in series in a field coil of an A.C. generator for intermittently controlling a field current supplied to the field coil in accordance with an output voltage from the A.C. generator in ord... | 09/12/2006 |
| 7062160 | Monitoring current in a motor during acceleration to verify motor frequency lock Method and apparatus for accelerating a motor from an intermediate velocity to a final operational velocity. The motor is accelerated from rest to the intermediate velocity through application of fixed duration drive pulses to the spindle motor. Once the motor reach... | 06/13/2006 |
| 7026780 | Method for stabilizing the movement of an articulated chain of a chain block, especially to prevent the formation of a resonance oscillation of the chain, and a chain block apparatus The invention concerns a method for stabilizing the motion of an articulated chain of a chain block, especially to prevent the formation of resonance oscillation of the chain, in which an articulated chain is led across a polygonal chain wheel with non-uniform pitch... | 04/11/2006 |
| 6970643 | Radiator having a fan in variable rotation speed A radiator includes a voltage regulator for providing a reference voltage, a fan including a power end connected to the reference voltage via a first resistor and a feedback end for outputting a pulse signal indicating the rotation speed of the fan, an integration c... | 11/29/2005 |
| 6703803 | Fan motor driving circuit A fan motor driving circuit of the present invention comprises a device for detecting a power source voltage and outputting a voltage in proportion to a difference between the power source voltage and a predetermined rated voltage when the power source vo... | 03/09/2004 |
| 6633145 | Circuit for improved back EMF detection A system and method of advancing the commutation sequence of a brushless DC motor is provided. The motor having a plurality of coils, each of the coils coupled together at one end to a common center tap and coupled at an opposite end, through a respective... | 10/14/2003 |
| 6438321 | Control of high speed DC motor vertical voltage vector component A motor controller utilizes sensors to detect the rotational speed and relative position of the motor rotor and generates a voltage vector to maintain the motor current in phase with the EMF before a voltage limit is reached. The approximate actual speed ... | 08/20/2002 |
| 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 |
| 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 noise, while maintaining an acceptable charge rate. The gate of... | 01/12/1999 |
| 5834911 | Brushless DC motor capable of being started stably In a state of synchronous operation in which a voltage and a frequency of an inverter output are increased in a stage of starting, when it is decided that a voltage difference signal is not at a specified level by a voltage difference signal level decidin... | 11/10/1998 |
| 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 being activated by a separate analog switch which can complete... | 09/01/1998 |
| 5652825 | Power supply for low-voltage DC motor An improved power supply for converting any of various standard national AC network voltages to low-voltage DC power suitable for driving a 1 or 2-watt device, such as a fan, features a semiconductor control circuit (18, FET 46) which chops each half-wave... | 07/29/1997 |
| 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 |
| 5015928 | Universal series motor with speed limiting circuit to protect the motor from overspeeding during relatively-small loads A shunt element and a voltage detection circuit are connected in parallel across the armature of a universal series motor. At relatively light loads on the motor, the armature speed increases, thereby increasing the back e.m.f. of the armature. The voltag... | 05/14/1991 |
| 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 |
| 4955431 | Cooling device for an internal combustion engine and method for controlling such a cooling device A device and method for cooling an internal combustion engine is disclosed in which a simple control circuit constructed of relatively inexpensive components enables the rotational speed of an electric motor employed in the cooling device to be controlled... | 09/11/1990 |
| 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 |
| 4831313 | Two speed motor controller An electronic control for regulating the operation of a two-speed motor in a heat transfer system such as a heat pump or air conditioner. The control receives high and low demand signals from a thermostat and a motor unit operates at high and low speeds i... | 05/16/1989 |
| 4803410 | Variable duty ratio speed controller for DC motors A speed controller for a DC motor includes a semiconductor switching device connected in series with it in a DC power circuit. The switching circuit is turned on and off with a duty ratio variable as a function of motor load. A time constant circuit inclu... | 02/07/1989 |
| 4801855 | Method and system for controlling chopper The magnitude of current change for the change of input voltage or for the change of speed of rotation of the shunt motor is utilized, i.e., the shunt characteristics are utilized, and the voltage applied to the motor is limited so that the armature curre... | 01/31/1989 |
| 4780653 | Anti-stall motor drive An anti-stall motor drive circuit for a very slow running permanent magnet d.c. motor is disclosed. The slow running speed of the motor sometimes allows an insulating film to build up between the brushes and the commutator which causes the stalled conditi... | 10/25/1988 |
| 4722669 | Fan speed controller The fan speed controller disclosed herein is particularly useful in the cooling of electronic equipment and provides a feedback control characteristic from an exhaust air temperature sensor such that the change in outlet temperature over the range of air ... | 02/02/1988 |
| 4707643 | Rotary speed ratio control for a multiple rotary drive system for a textile-working machine In the drive for a textile working machine, for the synchronized yet independently operable drive of at least two shafts, brake-clutch units associated with each shaft are provided, which are driven by a common electric motor. To achieve a regulation and ... | 11/17/1987 |
| 4703248 | Switching arrangement for full-wave power control which is insensitive to mains voltage fluctuations A switching arrangement for full-wave power control comprising a triac (2), the control electrode of which is preceded by a trigger diode, the control voltage being taken from an RC section having at least one potentiometer (9), which effects a phase shif... | 10/27/1987 |
| 4680517 | Motor drive control device A motor drive control device to control the speed of a motor includes a drive control section in series with the motor. Only, when a speed setting voltage exceeds a first predetermined value the, drive control section conducts to energize the motor, and w... | 07/14/1987 |
| 4645991 | Apparatus for removing torque ripples in direct-current motors An apparatus for removing torque ripples comprises a permanent magnet rotor, position sensors, stator armature coils, an operational circuit for effecting an arithmetic operation on detected signals from the position sensors, and a control circuit for dri... | 02/24/1987 |
| 4618805 | Device for regulating rotary speed of an alternating current electric motor A device for independently regulating rotary speed and torque of an alternating current electric motor whose armature winding is connected as a branch of a bridge circuit balanced for a fixed rotary speed and a fixed operational voltage of the motor. The ... | 10/21/1986 |
| 4616162 | Speed selection control for vehicle mounted electric accessory motor A speed selection control is provided for a DC electric accessory motor having an armature winding and being mounted on a vehicle having a high reactance, multiphase alternator with a diode bridge rectifying output circuit, a battery connected across the ... | 10/07/1986 |
| 4575664 | Tachometer check apparatus An electronic motor control system is taught herein which utilizes a tachometer check circuit. The tachometer check circuit is an electrical circuit which is interconnected with the output terminals of the tachometer. The circuit is utilized when the tach... | 03/11/1986 |
| 4547715 | Current control circuit An overcurrent protection circuit for inductive loads such as motors is provided. A source voltage is input to a divider circuit including semiconductor switching devices. The inductive load is also connected to the voltage source through the divider circ... | 10/15/1985 |
| 4533856 | Submerged scraper conveyor automatic speed control In a submerged scraper conveyor (10), an automatic voltage control system controls the speed of variable speed drive (32), in turn the speed of follower sprocket (22) and in turn the speed of drag chain (16) as a function of the torque on the headshaft (2... | 08/06/1985 |
