Composite magnet of electromagnet and permanent magnet, and eddy current retarder
US6756870B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 18, 2001 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Jun 8, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K7/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A composite magnet has an iron core, a coil around the iron core, and a permanent magnet in the iron core. A first eddy current retarder includes a brake drum with a rotatable shaft, and a stationary magnet unit inside the inner peripheral surface of the brake drum and having an annular base portion, iron core portions, a support member having magnetic pole pieces at the ends of the iron core portions and opposed to the brake drum, electromagnets, and a permanent magnet in each of the iron core portions with its magnetic pole surface directed in the radial direction. A second eddy current retarder includes a stationary brake drum, an annular magnet support member coupled to a rotatable shaft and inside the inner peripheral surface of the brake drum, and magnets outside the magnet support member and opposed to the surface of the brake drum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.