Stepping motor having rotor sections with permanent magnets disposed thereon at a constant pitch
US5760503A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 21, 1996 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Jun 21, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K37/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A stepping motor includes a stator and a rotor. The stator has pole teeth projecting from the inner surface at a constant pitch. The rotor has first through fourth rotor sections, and permanent magnets are embedded into the outer surface of each of the first through fourth rotor sections at a pitch equal to the pitch of the pole teeth. Two coils are provided in the stator so as to generate looped magnetic fluxes in the stator. A first offset corresponding to one half of the pitch of the permanent magnets is provided between each permanent magnet of the first rotor section and a correspond permanent magnet of the second rotor section, and a second offset equal to the first offset is provided between each permanent magnet of the third rotor section and a correspond permanent magnet of the fourth rotor section. Further, a third offset corresponding to a quarter of the pitch of the permanent magnets is provided between each permanent magnet of the second rotor section and a correspond permanent magnet of the third rotor section. When current is supplied to the coils, driving forces are generated at the permanent magnets of the first and second rotor sections as well as at the permanent…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.