Contact bridge with blow magnets
US8946580B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 2009 |
| Grant date | Feb 3, 2015 |
| Priority date | — |
| Expiry date | Nov 4, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2001/545
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention relates to contactors for unidirectional DC operation with permanent magnetic arc extinguishing. In addition to the blow magnets, the contactors are equipped with compensatory permanent magnets for compensating the magnetic field in the vicinity of the contact bridge in order to prevent contact levitation, i.e., an uncontrolled opening of the contacts that is due to a magnetic force generated by a strong current flowing through the contact bridge. To this end, the compensatory permanent magnets are arranged in the vicinity of the contact bridge and polarized in the opposite direction of the blow magnets. The magnetic field of the compensatory magnets and the current flowing through the contact bridge are generating a magnetic force that acts on the contact bridge and tends to keep the electrical contacts closed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.