Patent application number | Description | Published |
20100215491 | ROTOR ASSEMBLY - A rotor assembly that includes a shaft to which are mounted an impeller, a rotor core and a bearing cartridge. The bearing cartridge is mounted between the impeller and the rotor core and comprises a pair of bearings, a spring that applies a preload to each of the bearings, and a sleeve that surrounds the bearings. | 08-26-2010 |
20100225196 | ELECTRIC MACHINE - An electric machine that includes a permanent-magnet rotor and a stator. The stator includes a plurality of poles, each pole having a leading edge and a trailing edge relative to the direction of rotation of the rotor. The leading edge of each pole is thicker than the trailing edge in a direction normal to the rotational axis of the rotor. | 09-09-2010 |
20100225197 | STATOR CORE - A stator core that includes a pair of poles separated by an air gap. Each pole includes a first side adjacent the air gap and a second opposite side remote from the air gap. A pole arc is formed in the first side and an arcuate mounting recess is formed in the second side of each pole. Additionally, an electric machine that includes the stator core. | 09-09-2010 |
20100225207 | ELECTRIC MACHINE - An electric machine that includes a stator and a Hall-effect sensor. The stator includes a pair of asymmetric poles and the sensor is oriented such that the plane of the sensor is substantially parallel to armature field lines passing through the sensor. | 09-09-2010 |
20110254476 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes rectifying an alternating voltage to provide a rectified voltage having a ripple of at least 50%, exciting a winding of the motor with the rectified voltage, and performing a first process or a second process in response to current in the winding exceeding a threshold that is proportional to the rectified voltage. The first process includes freewheeling the winding, while the second process includes continuing to excite the winding for an overrun period and freewheeling the winding at the end of the overrun period. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254480 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes rectifying an alternating voltage to provide a rectified voltage, exciting a winding of the motor with the rectified voltage for a conduction period over each electrical half-cycle of the motor, and updating the conduction period in response to a zero-crossing in the alternating voltage. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254481 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes rectifying an alternating voltage to provide a rectified voltage, exciting a winding of the motor with the rectified voltage and freewheeling the winding when current in the winding exceeds a threshold. The winding is freewheeled for a freewheel period, which is updated in response to a zero-crossing in the alternating voltage. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254483 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes rectifying an alternating voltage to provide a rectified voltage, and exciting a winding of the motor with the rectified voltage. The winding is excited in advance of predetermined rotor positions by an advance period that is updated in response to a zero-crossing in the alternating voltage. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254485 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes exciting a winding of the motor for a conduction period over each electrical half-cycle of the motor. The length of the conduction period is defined by a waveform that varies periodically with time. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254487 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes exciting a winding of the motor in advance of predetermined rotor positions by an advance period. The length of the advance period is defined by a waveform that varies periodically with time. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254488 | CONTROL OF A BRUSHLESS PERMANENT-MAGNET MOTOR - A method of controlling a brushless permanent-magnet motor that includes rectifying an alternating voltage to provide a rectified voltage having a ripple of at least 50%, and exciting a winding of the motor with the rectified voltage. The winding is excited in advance of zero-crossings of back EMF by an advance period and is excited for a conduction period over each electrical half-cycle of the motor. The advance period and/or the conduction period are then adjusted in response to changes in the speed of the motor and/or the RMS value of the alternating voltage so as to maintain constant average power. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20110254489 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes exciting a winding of the motor until current in the winding exceeds a threshold, and then continuing to excite the winding for an overrun period. The length of the overrun period is adjusted in response to a change in one of time, motor speed and excitation voltage. Additionally, a control system that implements the method, and a motor system that incorporates the control system. | 10-20-2011 |
20140009095 | CONTROL OF A BRUSHLESS MOTOR - A method of controlling a brushless motor that includes sensing a temperature and using the sensed temperature to define a current limit. A lower current limit is then defined for a lower sensed temperature. A winding of the motor is sequentially energised and de-energised, with the winding being de-energised when current in the winding exceeds the defined current limit. | 01-09-2014 |
20140009099 | METHOD OF PREHEATING A BRUSHLESS MOTOR - A method of preheating a brushless motor that includes sequentially energising and de-energising a phase winding over one or more drive periods. The phase winding is energised in the same direction throughout each drive period so as to lock a rotor of the motor at an aligned position. | 01-09-2014 |