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| Number | Title | Issue Date |
| 7340820 | Machine stator fabrication method A machine stator is fabricated by positioning pre-wound stator windings with respect to a laminated stator yoke and directly molding composite tooth tips into contact with respective teeth of the laminated stator yoke, or by positioning pre-wound stator windings aro... | 03/11/2008 |
| 7299664 | Device for controlling motor in washing machine and method for controlling process of washing machine by using the same Device for controlling a motor in a washing machine and a method for controlling a process of a washing machine by using the same, the device including a motor, a power source part for supplying a voltage to the motor, a plurality of torque varying parts parallel to... | 11/27/2007 |
| 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 |
| 7235948 | Forklift and method for controlling induction motor applied to the same A forklift having a cargo apparatus, the responsiveness of which to the operation by a user is improved. The forklift has: a DSP which generates a frequency instruction f* in response to the operation to a cargo apparatus operation lever, a voltage instruction V* fr... | 06/26/2007 |
| 7224557 | Method and system of controlling asynchronous contactors for a multi-phase electric load Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect... | 05/29/2007 |
| 7211974 | Motor and drive control system thereof Provided is a motor having a magnetic polar unit in which a permanent magnetic polar array having arranged therein alternately a plurality of permanent magnetic polar elements in alternate opposite poles is made to face a plurality of electromagnetic coil arrays alt... | 05/01/2007 |
| 7190086 | Wind energy plant with an asynchronous machine for determining the azimuth position An asynchronous machine has a first rotor/stator arrangement in which the rotor is connected to a shaft, and a method of controlling such an asynchronous machine is provided. A drive is provided which permits nullification of the play of the mechanical components in... | 03/13/2007 |
| 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 |
| 7135833 | Motor control for flux-reduced braking A method and apparatus for braking an AC motor in the higher portion of its speed range includes substantially reducing flux before applying reverse torque commands to brake the motor. A DC link bus regulator is employed to prevent increases in bus voltage and frequ... | 11/14/2006 |
| 7122992 | Inverter system for driving induction motor An inverter system for driving an induction motor is disclosed. The inverter system for driving an induction motor comprises: a rectifying circuit for rectifying a three-phase AC voltage and outputting the same; a smoothing circuit for smoothing the rectified voltag... | 10/17/2006 |
| 7034477 | Domestic electrical appliance including an electric motor Domestic electrical appliance, including a universal electric motor powered by direct current via an electrical circuit linked to a DC electrical voltage source, said circuit including a chopper arrangement, including a capacitor in parallel with the DC voltage sour... | 04/25/2006 |
| 7013207 | Automotive performance meter Methods, systems and circuits for analyzing the performance of a vehicle having an electrical system are provided which determine a shift point while the vehicle is being driven. The shift point is determined using acceleration data and RPM data generated from the e... | 03/14/2006 |
| 6973377 | Automotive performance meter Methods, systems and circuits for analyzing the performance of a vehicle having an electrical system are provided which determine a shift point while the vehicle is being driven. The shift point is determined using acceleration data and RPM data generated from the e... | 12/06/2005 |
| 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 |
| 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 |
| 6696813 | Open-loop synchronizer for a slide out room An open-loop system for synchronizing movement of a slide out room includes a pair of motors connected to extendable members which support the room during movement between an extended and a retracted position for driving the extendable members, a controll... | 02/24/2004 |
| 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 |
| 5914583 | Motor control for box printing equipment A motor control system for controlling the operating speed and direction of a three-phase induction motor. The invention particularly finds use for bringing a rotary printing cylinder precisely into register for processing products in sheet form, such as ... | 06/22/1999 |
| 5777450 | Method and apparatus for control in power failure A method and apparatus for controlling, in power failure, such a machine that a workpiece and a tool are required to be always synchronized in their motion. The method and apparatus allow the tool and workpiece to move back and stop at a safe area without... | 07/07/1998 |
| 5726550 | Motor control system for centrifuge A motor control system for controlling power supplied to an electric motor rotating a rotor employed in a centrifuge is provided. The motor control system includes first, second, and third converters and first and second smoothing capacitors. In a motor p... | 03/10/1998 |
| 5703459 | Driver for an induction motor A driver for an induction motor includes a voltage limiter which limits an upper limit value of an output voltage from an invertor circuit in accordance with an output frequency command, a lowest frequency limiter which limits a lower limit of an output f... | 12/30/1997 |
| 5179336 | Method for decreasing the speed of an alternating current motor The invention is carried out by providing an adjustable frequency power supply connected to an alternating current induction motor which is rotated at speeds in excess of 60 hertz. A plurality of sequential frequency ranges are selected which, together, c... | 01/12/1993 |
| 5149998 | Eddy current drive dynamic braking system for heat reduction A dynamic braking means for a variable speed dynamoelectric eddy current drive consists of an ac motor (4) rotationally coupled through a shaft (6) to an inductor drum assembly (13) of an eddy current coupling (3), where an annular field coil 12 generates... | 09/22/1992 |
| 5077508 | Method and apparatus for determining load holding torque A motor control method and apparatus for a hoist is disclosed in which a drive motor is connected to an adjustable frequency power supply in which the frequency of the power supplied to the motor can be selectively varied. At the initiation of a hoist ope... | 12/31/1991 |
| 5070290 | Alternating current motor control system with emergency control responsive to failure of power supply A control system for an alternating current motor, such as an elevator hoisting induction motor, in response to failure of power supply, such as service interruption, phase open and so forth, performs in a first emergency control mode and in a second emer... | 12/03/1991 |
| 5049793 | Method of controlling V/F inverter for machines having mechanical braking systems There is disclosed a method of controlling a voltage-to-frequency inverter which controls an induction motor by the use of an open-loop system. The motor drives a machine such as a crane, and is braked by a mechanical brake. When the machine is started or... | 09/17/1991 |
| 5006045 | Scroll compressor with reverse rotation speed limiter Here is disclosed an air conditioner comprising a scroll type compressor and a brushless DC motor having a rotor provided with a permanent magnet and a stator provided with a sensor adapted to detect a relative position of said rotor and said stator. Here... | 04/09/1991 |
| 4961042 | Device for controlling AC motor A device for controlling an AC motor for a fork lift truck comprises a detector to detect direction of rotation of an AC motor. The direction of rotation thus detected is compared with a desired direction of rotation of the AC motor, and the AC motor is c... | 10/02/1990 |
| 4914366 | Positioning control system A plurality of speed-sliding compensation amount functions are stored in a sliding compensation amount data memory and one of these functions is selected in response to input of a selection signal. In the selected function, sliding compensation amount dat... | 04/03/1990 |
| 4777420 | Induction motor control apparatus and method An AC induction motor is energized by a voltage fed inverter coupled with a DC power source and is controlled in response to a torque request signal that is provided to accelerate or decelerate the motor as desired to maintain a desired torque output. The... | 10/11/1988 |
| 4772808 | Control device for electrical appliances A control device for supplying current to electrical appliances and particularly appliances having single phase capacitor start motors wherein the control device includes a changeover switch which is mounted between a source of power and the appliance mot... | 09/20/1988 |
| 4761600 | Dynamic brake control A dynamic brake control system for an alternating current motor powered by a variable voltage, variable frequency inverter which regulates the speed of the motor. An AC to DC converter converts AC line power to DC power with the DC power being transferred... | 08/02/1988 |
| 4712054 | Controller with two modes of braking induction motors To a controller utilizing thyristors have been added delayed resetting circuits connected to timing circuits for enabling delayed firing, and also circuits for inverting polarity of error signal in order to accommodate regenerative and reverse-plug brakin... | 12/08/1987 |
| 4651073 | Positioning control device for an electric motor A rotational position, velocity and acceleration of an electrical motor are detected and an amount of overrun produced when the motor has stopped is estimated from the detected velocity and acceleration, and at least one of motor position detection data a... | 03/17/1987 |
| 4460862 | Electronic speed and slowing down control with intrinsic safety An electronic system is disclosed for controlling both the ascendant and the descendant speed in vertical machines such as cranes, elevators, etc., in which it is required to lift different loads in a regulated and self-controlled manner, laying aside the... | 07/17/1984 |
| 4417191 | Method and circuit for D.C. braking a three-phase asynchronous machine A method for D.C. braking a three-phase asynchronous machine and a circuit arrangement useful in implementing the method. For braking, the first and third stator windings are separated from their phases and a pulsating direct current is caused to flow fro... | 11/22/1983 |
| 4395670 | Hybrid electrical braking method and system for tool equipment having induction motor drives A hybrid electrical braking method and system are provided for tool equipment having induction motor drives. This hybrid electrical braking can be used to advantage in various types of induction motor driven tool equipment where it is desirable rapidly to... | 07/26/1983 |
| 4392098 | RPM Sensor for electronic motor braking The motor braking circuit for use with an alternating current motor and an AC power source includes a power circuit for supplying a DC braking current to the AC motor and a motor speed sensor which causes a mechanical brake to engage the AC motor and its ... | 07/05/1983 |
| 4340131 | Operational control system for lift and elevator machinery Operational control system for lift and elevator machinery adapted for electrodynamic braking, said operational control system being adapted to be connected to the machinery of existing lift or elevator equipment. The operational control system is designe... | 07/20/1982 |
| 4335342 | Reciprocating drive system for a body such as a carriage supporting electrostatic means for spraying a pulverized material, the system including an asynchronous squirrel cage motor A reciprocating drive system moves a body of defined inertia, such as a carriage supporting electrostatic spraying means, at full speed between two points at which the direction of movement is reversed. The drive system includes an electric motor with pol... | 06/15/1982 |
