Class / Patent application number | Description | Number of patent applications / Date published |
318244000 | ALTERNATING CURRENT COMMUTATING MOTORS | 17 |
20090039807 | MOTOR CONTROLLER - In one aspect, a control circuit to control a speed of a motor includes a PWM oscillator configured to generate a PWM output signal having a duty cycle. The speed of the motor is controlled by the PWM output signal to be proportional to the duty cycle. The control circuit also includes a duty cycle control circuit responsive to a duty cycle selection signal and coupled to the PWM oscillator. The duty cycle control circuit is configured to compare a voltage reference and a supply voltage. The duty cycle control circuit controls the duty cycle of the PWM output signal to be inversely proportional to the supply voltage. | 02-12-2009 |
20090058330 | DRIVING A MULTI-PHASED MOTOR - Motor control circuitry reduces the amount of driving voltage profile data stored in a profile datastore to completely rotate the phased motor. The stored driving voltage profile data defines driving voltages samples applied during a limited portion of the electrical period required to completely rotate the phased motor. For example, in one implementation, only one-sixth of the electrical period is defined and stored in a profile datastore. The driving voltage samples for another three-sixths of the electrical period are derived from this one-sixth profile (e.g., reversing, inverted, reversed and inverted), and the driving voltage samples for another two-sixths of the electrical period are based on saturated levels at the power supply voltage and a neutral voltage (e.g., ground). The described motor control circuitry can also provide improved torque at low power supply levels, particularly when saturated portions of the driving voltage profile exceed sixty degrees. | 03-05-2009 |
20110148331 | MOTION CONTROL SYSTEM SELF-CALIBRATING - A motion control system including components such as an accelerometer for detecting zero force positions and for self-calibrating the motion control system. The motion control system may be implemented in an active seat suspension. | 06-23-2011 |
20110148332 | POWER TOOL - According to an aspect of the present invention, there is provided a power tool including: a motor; a switching device that switches over, in response to a conduction angle thereof, an AC voltage to be applied to the motor; a rotation speed setting unit that sets a target rotation speed of the motor; a rotation speed detection unit that detects an actual rotation speed of the motor; and a controller that determines the conduction angle by comparing the actual rotation speed with the target rotation speed and that controls the switching device by use of the conduction angle based on a maximum conduction angle, the maximum conduction angle being set in accordance with the target rotation speed. | 06-23-2011 |
20110204831 | DRIVE DEVICE FOR ALTERNATING CURRENT MOTOR AND ELECTRIC MOTOR VEHICLE - Provided is a drive device for an alternating current motor which performs vector control on sensorless driving of the alternating current motor in an extremely low speed region without applying a harmonic voltage intentionally while maintaining an ideal PWM waveform. A current and a current change rate of the alternating current motor are detected, and a magnetic flux position inside of the alternating current motor is estimated and calculated in consideration of an output voltage of an inverter which causes this current change. The current change rate is generated on the basis of a pulse waveform of the inverter, and hence the magnetic flux position inside of the alternating current motor can be estimated and calculated without applying a harmonic wave intentionally. | 08-25-2011 |
20130169199 | METHOD FOR DETERMINING ROTATIONAL SPEED OF AN ELECTRIC MOTOR IN A POWER TOOL - An overspeed protection subsystem is provided for a power tool having an electric motor. The overspeed protection subsystem is comprised of: a motor switch coupled in series with the motor; a motor control module interfaced with the motor switch to control switching operation of the motor switch; and an overspeed detection module that determines rotational speed of the motor and disables the power tool when the rotational speed of the motor exceeds a threshold. | 07-04-2013 |
20130234630 | PROGRAMMABLE MOTOR AND METHOD - An electronically commutated motor is programmed by applying a low frequency mains supply ( | 09-12-2013 |
20150028779 | ELECTRIC MACHINE - An electric machine, including a set of at least six windings, voltage supply devices capable of supplying an electrical phase, and a circuit for controlling the voltage supply devices controlling phase shifts between the phases supplied by the voltage supply devices, each voltage supply device supplying a phase at the end common to two windings, the other end of the two windings being supplied by one of the two voltage supply devices supplying a phase of which the phase shift with the phase supplied by the voltage supply device is one of the two lowest, in terms of absolute value, among the phase shifts supplied by the voltage supply devices and the phase supplied by the voltage supply device. | 01-29-2015 |
318245000 | Universal or A.C.-D.C. motors | 9 |
20080284361 | Method and Circuit For Regulating the Speed of a Commutator Series-Wound Motor - The invention relates to a method and a circuit for regulating the speed of a commutator series-wound motor, especially a universal motor ( | 11-20-2008 |
20110018477 | METHOD AND DEVICE FOR OPERATING AN ELECTRIC DRIVE WITH THE AID OF A PHASE ANGLE CONTROL - The invention relates to a method for operating an electric motor ( | 01-27-2011 |
20120249023 | Disconnection from Mains using Switches for Power Tools - A method for operating a mains-operated electric motor for a power tool using switches, in particular semiconductor switches, includes monitoring the operation of the switches using an electronic controller for operating safety. | 10-04-2012 |
20130069566 | Electronically controlled universal motor - An electric motor apparatus comprising a rotor component rotating with respect to a stator component. A rotational position indicator generates rotational position information indicative of a relative orientation of the rotor and stator components. A rotor winding control unit is fixedly mounted on the rotor component and is coupled to a rotor supply voltage supplied to the rotor component. The rotor control unit generates a rotor waveform in dependence on the rotational position information and applies the rotor waveform to a rotor winding arrangement. A stator winding waveform generator generates a stator waveform in dependence on the rotational position information and applies the stator waveform to a stator winding arrangement. The rotor waveform and stator waveform are generated in synchronization with the relative orientation of the rotor and stator components in order to synchronize mutual interactions of the rotor winding arrangement and the stator winding arrangement with the relative orientation. | 03-21-2013 |
20150108926 | Method and Device for Electrodynamic Braking of a Universal Motor - A method and device for electrodynamic braking of a universal motor. The method comprises the steps of continuously ascertaining a rotational speed of the universal motor, temporarily, periodically short-circuiting an armature of the universal motor with a semiconductor switch, and regulating firing angles of the semiconductor switch with a regulating device. The regulating device regulates firing angles of the semiconductor switch such that the rotational speed of the universal motor is adapted with minimal deviation to a rotational speed of a target rotational speed profile. | 04-23-2015 |
20150108927 | Method and Device for the Electrodynamic Braking of a Universal Motor - A method and device for the electrodynamic braking of a universal motor. The method comprises continuously ascertaining a rotational speed of the universal motor, temporarily, periodically short-circuiting an armature of the universal motor with a semiconductor switch to brake the universal motor, and setting firing angles of the semiconductor switch according to an indexed mapping of firing angles to target rotational speeds of the universal motor. Each of the set firing angles is adapted to an ascertained rotational speed value. | 04-23-2015 |
20150137716 | METHOD FOR ACTIVATING AN ELECTRIC MACHINE - In a method for activating an electric machine having a rotor, a stator winding having multiple phases and a rectifier having multiple half-bridges corresponding to the number of phases, which each have active switching elements, alternating current signals, which are phase-offset to one another by switching the switching elements, are applied to the phases in a first motor operating mode in which the rotor rotates above a limiting speed, and in a second motor operating mode, in which the rotor rotates below the limiting speed, constant direct-current signals are at least partially applied to the phases by switching the switching elements as a function of an instantaneous angle position of the rotor, the direct-current signals being selected in such a way that a current flow does not exceed a predefined maximum current absolute value through any of the phases. | 05-21-2015 |
20150340974 | Electronic Braking for a Universal Motor in a Power Tool - A power system is provided comprising an electric universal motor including an armature rotatable coupled to an armature shaft and a commutator disposed on an armature shaft, a pair of brushes engaging the commutator, and a field having at least two field windings electrically coupled in series with the pair of brushes. The power system includes a power line having two terminals arranged to provide alternating-current (AC) power from a power supply, and a power switch provided in series with the field windings on a power line to provide AC power from the terminals to the motor when the power switch is closed. An electronic brake module is provided in the power system and configured to generate a braking force to stop the motor when the switch is opened, the electronic brake module comprising: a solid-state semiconductor switch arranged across the motor armature and the pair of brushes, a first diode arranged between a first node of the power line and the semiconductor switch, and a second diode arranged between a second node of the power line and the semiconductor switch, wherein the first node is arranged between one of the terminals and the power switch, and the second node is arranged between the power switch and the armature. A controller is provided in the power system and configured to initiate a braking mode of operation to close the semiconductor switch when the power switch is opened. | 11-26-2015 |
20160020443 | Power Tool System - A power tool system includes a first power tool having a first power tool rated voltage, a second power tool having a second power tool rated voltage that is different from the first power tool rated voltage, and a first battery pack coupleable to the first power tool and to the second power tool. The first battery pack is switchable between a first configuration having a first battery pack rated voltage that corresponds to the first power tool rated voltage such that the first battery pack enables operation of the first power tool, and a second configuration having a convertible battery pack rated voltage that corresponds to the second power tool rated voltage such that the battery pack enables operation of the second power tool. | 01-21-2016 |