Did You Know...
...that Charles Goodyear performed some of his experiments on rubber while in debtor's prison? He was there so often he referred to it as his "hotel". Chronically in debt because of poor business sense and ill health, Goodyear depended on the generosity of friends and family. Even after he unlocked the secret to vulcanizing rubber, he was unable to improve his financial situation. When he died, his estate was $200,000 in debt.
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| Number | Title | Issue Date |
| 8035332 | Motor apparatus and method A method of operating a motor, the method comprising: operating a motor at a first speed; operating the motor in negative slip; imbalancing at least one phase of the motor to dissipate regeneration energy using windings of the motor; and wherein a next motor speed i... | 10/11/2011 |
| 7358620 | Methods and apparatus for ride-through operation of a complementary device to a transient power source In accordance with certain exemplary embodiments, the present technique provides methods and apparatus for providing operating power to a complementary device to an induction device based uninterruptible power source (UPS) via a direct current (dc) bus. In one embod... | 04/15/2008 |
| 7327110 | Drive circuit for braking a motor during a malfunction A drive system with an electric motor is described, which includes an integrated armature short-circuit brake and a mechanical brake. If the electric motor cannot be controllably slowed down, a control signal is applied at an activation time to the integrated armatu... | 02/05/2008 |
| 7268514 | Motor control for stopping a load and detecting mechanical brake slippage A method and apparatus for stopping an AC motor that is controlling a load while detecting mechanical brake slippage of a mechanical brake for holding the load against movement includes a controller for decreasing torque-producing current commands from the drive whi... | 09/11/2007 |
| 7242163 | System and method for clamp current regulation in field-weakening operation of permanent magnet (PM) machines A device to regulate current produced by a permanent magnet machine responsive to a plurality of phase current signals. The motor produces torque for application on a shaft. A processing and drive circuit responsive to a direct current command signal and a quadratur... | 07/10/2007 |
| 7212391 | Grounded isolation system An system and method are disclosed for isolating and grounding a load device, where grounding only occurs after the voltage(s) on the load device have been reduced to acceptable levels. The system includes power and grounding contacts, a sensing device, and a contro... | 05/01/2007 |
| 7193380 | Method for rotating a printer paper-feed roller A method for rotating a printer paper-feed roller wherein the roller is driven by a DC (direct current) motor. A feedback-control signal is applied to the motor until the roller reaches a desired rotational position. The feedback-control signal is a function of an e... | 03/20/2007 |
| 7190146 | Control system and method for an overhead bridge crane Included herein is a system and method for controlling a velocity vector of an overhead crane. A motor is attached to the crane and is positioned to move the overhead crane and has an output vector including a rotational direction and a rotational speed. A variable ... | 03/13/2007 |
| 7187155 | Leakage inductance saturation compensation for a slip control technique of a motor drive An electronic drive for vector control of an induction motor controls slip and operating frequency in response to changes in stator voltage. The drive includes a torque control loop, a flux control loop and a frequency control loop. The control is based on a command... | 03/06/2007 |
| 7170245 | Motor power supply control apparatus A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking re... | 01/30/2007 |
| 7161325 | Lead-angle control method and device for operating permanent magnet synchronous motor in flux weakening regions A lead-angle control device according to the present invention includes: a space voltage vector controller calculating effective vector application times necessary for obtaining output voltage vectors of an inverter from stationary-coordinate-system instruction volt... | 01/09/2007 |
| 7148652 | Method and apparatus for determining and handling brake failures in open loop variable frequency drive motors A controller for a variable frequency drive monitors electrical power from a variable frequency drive motor while a brake is maintaining a load driven or moved by the motor without requiring additional feedback components of a closed loop configuration. If excess el... | 12/12/2006 |
| 7106012 | Electronic control unit, electric power-assisted steering device and transmission ratio-variable steering unit An electronic control unit for producing a sufficiently boosted voltage even when a supply voltage becomes high includes an inverter that drives switching elements and converts a DC voltage into an AC voltage, and booster means which boosts a DC voltage that is inpu... | 09/12/2006 |
| 7102314 | Brushless motor control apparatus having overheat protecting function A brushless motor control apparatus detects a phase current flowing in a brushless motor, converts the phase current to a vector current including a d-axis current of a magnetic flux direction component and a q-axis current of a torque direction component orthogonal... | 09/05/2006 |
| 7042178 | Motor driving apparatus A motor driving apparatus including a regeneration control function and a power storage device for accumulating a regenerative current and for supplying an inverter section with electric power during acceleration. The inverter section is connected to a converter sec... | 05/09/2006 |
| 7023168 | Field weakening motor control system and method A control system for an electric machine includes a flux weakening module, which includes a voltage magnitude calculator that receives d-axis and q-axis command voltages and that generates a voltage magnitude. An error circuit compares the voltage magnitude to a ref... | 04/04/2006 |
| RE39023 | Power output apparatus and method of controlling the same While a ring gear shaft 126 linked with a drive shaft rotates, a power output apparatus 110 applies a torque to a first motor MG1 attached to a sun gear shaft 125, thereby abruptly increasing a revolving speed of an engine 150, to ... | 03/21/2006 |
| 6945752 | Azimuthal driving system for wind turbines Wind power installations generally have an active drive for wind direction tracking. The active drive rotates the machine housing of the wind power installation in such a way that the rotor blades of the rotor are oriented in the direction of the wind. Multiple azim... | 09/20/2005 |
| 6930458 | Apparatus for controlling deceleration of DC motor An apparatus for controlling deceleration of a DC motor which is driven in a forward operating direction with a forward-drive electric current applied thereto by a forward driving device, wherein the forward motor driving device applies the forward-drive electric cu... | 08/16/2005 |
| 6930457 | DC motor brush filter circuit The present invention provides a motor control circuit including a motor with a motor winding and a brush, a battery, a relay, and a ground return circuit. The battery is for energizing the motor. The relay selectively provides connection between the battery and the... | 08/16/2005 |
| 6927502 | Three-phase asynchronous motor driven azimuthal drive for wind power installations Wind power installations generally have an active drive for wind direction tracking. The active drive rotates the machine housing of the wind power installation in such a way that the rotor blades of the rotor are oriented in the direction of the wind. That drive wh... | 08/09/2005 |
| 6879123 | Device to control a 3-phase motor A device to control a 3-phase motor having an inverter connected to each phase terminal and a brake to arrest the 3-phase motor, includes a power supply to supply power to the brake and the inverter at the same time based on a predetermined synchronization signal. T... | 04/12/2005 |
| 6876171 | Driving apparatus and method of three phase induction motor A driving apparatus of a three-phase induction motor includes: a three-phase power supply unit for supplying three-phase power; a rectifier for rectifying the three phase voltage supplied from the three phase power supply unit; a voltage reducing unit for reducing a... | 04/05/2005 |
| 6870344 | Motor control system An inverter part having a switching unit for applying a three-phase AC voltage to a motor, a lock detection unit for detecting a lock state of the motor and also generating a lock detection signal by the detection, and a current control unit for passing a d-shaft ar... | 03/22/2005 |
| 6741050 | Method of controlling and switching for braking an electronically commutated electrical motor A control method and a switching circuit for braking an electronically commutated electrical motor, wherein operation is in a phase period (T) of an inverter relative to at lest one winding, sequentially, both in a motoring mode and a generating operating mode using... | 05/25/2004 |
| 6741062 | Circuit configuration for supplying an electric motor A circuit configuration supplies an electric motor with a stator and a rotor. The stator has a large number of electromagnets, arranged in particular in the form of a ring, and the rotor has a large number of permanent magnets that are associated with the electromag... | 05/25/2004 |
| 6710573 | Method of controlling pulsed AC power PWM AC power is supplied to an induction motor or other AC load. The frequency and magnitude of the waveforms is controlled by detecting the peak voltage or width of the reverse EMF pulses at the commencement of the power waveform applied to the load, and then adjus... | 03/23/2004 |
| 6700347 | Speed varying device This invention is to provide a variable speed apparatus capable of equalizing a moving distance at the time of deceleration from deceleration start to deceleration completion in the case that a deceleration stop command is inputted during acceleration to ... | 03/02/2004 |
| 6667596 | Method and device for controlling deceleration in an induction machine In order to control the run-down of an induction machine, whose stator is connected to a singe-phase or polyphase AC main power supply system via an AC power controller which can be controlled by phase gating, a phase gating angle is first increased in st... | 12/23/2003 |
| 6650245 | Multi-functional hybrid contactor A multi-functional hybrid contactor has a motor protection function against an abnormal state in addition to the starting, running and stopping of the motor, the same effect as the case that an electronic motor protection relay (EMPR) is connected in para... | 11/18/2003 |
| 6646411 | Control method of compressor motor and inverter equipped with the same method A control device for a compressor motor and an inverter according to the present invention monitors the amplitude of a phase current of a three-phase DC motor. As the amplitude of the phase current approaches an overload condition of the inverter or motor... | 11/11/2003 |
| 6236177 | Braking and control circuit for electric power tools A power tool including a braking and control circuit. The braking and control circuit includes a microcontroller-based control means circuit. The microcontroller assures control of switch means, such as triacs, switches and relays, and ensures that brakin... | 05/22/2001 |
| 6208113 | System for controlling the rotation of AC motors The present invention relates to a system for controlling the rotation speed of AC motors, in particular single phase motors. In this case, a controllable electronic switching device is connected upstream of the motor and is actuated by a control unit suc... | 03/27/2001 |
| 6177772 | Method and apparatus for braking a polyphase DC motor A circuit and method for braking a disk drive when a power fault occurs has a circuit (10) for producing an output signal (28) indicating that the motor of the disk drive has slowed at least to a predetermined rotational speed after the occurrence of the ... | 01/23/2001 |
| 6147470 | Device for controlling induction motor and method of controlling the same A vector control apparatus having a DC braking function which is insusceptible to trip even upon DC braking and scarcely suffers vibration upon stoppage is provided. The control apparatus includes a DC braking control arithmetic unit 1 and switches S1, S3... | 11/14/2000 |
| 6121739 | Dosing pump and method for enhancing dosing precision The invention relates to a method for enhancing the dosing precision of a dosing pump which is driven by an asynchronous motor via an eccentric gear. The supply of the motor is cut off approximately half a cycle time before a desired dosing pause period o... | 09/19/2000 |
| 6118234 | Method and apparatus for effecting dynamic braking of a direct current motor A double pole, double throw switching arrangement for effecting dynamic rotor braking of user controlled operation of a reversible direct current servo motor. Two columns of stationary center and oppositely disposed side contacts are disposed in spaced pa... | 09/12/2000 |
| 5909097 | Method of stopping an electric motor-driven balancing machine main shaft A method of stopping an electric motor-driven balancing machine main shaft after an unbalance measuring run in a specific rotary angle stoppage position corresponding to a desired balancing rotary angle position provides that in the course of retardation ... | 06/01/1999 |
| 5896019 | Motor control device A motor control device that can control the rotational direction of a rotor with polarity in an initial position detection. The motor control device includes first metering voltage signal generating system for sequentially creating 2N-phase signals to an ... | 04/20/1999 |
| 5894211 | Electric machine An electric machine includes a rotor and a stator, a rotor position transducer being provided to detect the position of the rotor relative to the stator. Phase windings are sequentially energizable to drive the rotor. The rotor position transducer is powe... | 04/13/1999 |
