Two-phase brushless direct-current motor having single hall effect device
US6005320A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1999 |
| Grant date | Dec 21, 1999 |
| Priority date | — |
| Expiry date | Jun 22, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S310/03
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A two-phase brushless direct-current (BLDC) motor having a single Hall effect device. The BLDC motor includes a stator comprised of 2n coils grouping as first and second phase coils at a uniform interval, and a rotor which N-pole and S-pole magnets of the same number as that of the stator coils are alternately disposed, the 2n magnets forming n pairs, each pair of magnets are disposed at a uniform interval, wherein a distant ratio from the center of one N-pole magnet to the centers of the S-pole magnets adjacent the N-pole magnet is established into 1:1.4. Since 2n auxiliary magnets are disposed annularly on the rotor with the same length as each other corresponding to the N-pole and S-pole magnets, a single Hall effect device detects the magnetic pole by magnetic flux of the rotating auxiliary magnets and generates the rotating position signal of the rotor, so that a switching controller can activate the first and second phase coils alternately. Thus, the motor has a simple driving circuit, a high efficiency and a small torque ripple.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.