Brushless DC motor fan driven by an AC power source
AssigneeSunonwealth Electric Machine Industry Co., Ltd.
InventorsYin Rong Hong, Alex Horng
Life of this patent
Estimating the term…
Abstract
A brushless DC motor fan includes a rotor, a stator, a drive circuit, and a conversion circuit. An input of the conversion circuit is connected to an AC power source. The conversion circuit drops the voltage of the AC power source before connecting to a sensor element and a drive circuit. The drive circuit outputs alternately conducted current with positive/negative polarity to make the coil of the stator be alternately conducted, thereby generating an alternating magnetic field for driving the rotor.
Claims18
A brushless direct current motor fan driven by an alternating current power source, the brushless direct current motor fan comprising:
- a rotor including a shaft rod and a rotor permanent magnet with at least one set of north pole and south pole;
- a stator including a plurality of pole plates and a coil, the stator including a central hole, for an axle tube to be sleeved on;
- an axle tube, a bearing mounted inside for pivotally supporting a shaft, the axle tube being extended through the central hole of the stator;
- a drive circuit board including a sensor element and a plurality of electric elements to constitute a drive circuit;
- and
- a fixed plate including a plurality of electric elements mounted thereon to constitute a conversion circuit and including a power line adapted to be electrically connected to the alternating current power source;
- the alternating current being converted into a direct current power source after rectification, filtering and regulation by the conversion circuit, the direct current power source driving the drive circuit and cooperating with the sensor element that detects a change in polarity of the permanent magnet to thereby provide alternately conducted current with positive/negative polarity to the coil of the stator, thereby generating an alternating magnetic field for driving the rotor.
A brushless direct current motor fan driven by an alternating current power source, the brushless direct current motor fan comprising:
- a rotor including a shaft and a rotor permanent magnet with at least one set of north pole and south pole;
- a stator including a plurality of pole plates and a coil, the stator including a central hole for an axle tube to be sleeved on;
- an axle tube, a bearing mounted inside for pivotally supporting a shaft, the axle tube being extended through the central hole of the stator;
- a sensor element for detecting a change in polarity of the permanent magnet of the rotor and sending a pulse signal in response thereto;
- a drive circuit including an output connected to the coil of the stator, the drive circuit receiving the pulse signal from the sensor element and providing alternately conducted current with positive/negative polarity to the coil, thereby generating an alternating magnetic field to drive the rotor;
- and
- a conversion circuit including an input adapted to be electrically connected to the alternating current power source, the alternating current being converted into a direct current power source after half-wave or full wave rectification by the conversion circuit and then filtered by the conversion circuit to output a direct current power source that is electrically connected to the sensor element and the driving circuit.
Dependencies are inferred from the claim text.