US 8,946,580 B2 · Contact bridge with blow magnets

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.

Claims12

Dependent claims

A contactor comprising

a contact bridge;
a first and a second contact arranged at respective ends of the contact bridge;
a first and a second permanent magnet arranged in the vicinity of the first and the second contact respectively, the first and the second permanent magnets being polarized in the same direction such that an arc generated at the first or the second contact is blown in a direction away from the contact bridge;
and
a third permanent magnet arranged in the vicinity of the contact bridge and between the first and the second permanent magnets, the third permanent magnet being arranged vertically in line with the first and the second permanent magnets, the third permanent magnet being polarized in a direction opposite to the first and the second permanent magnets, the first, second, and third permanent magnets are positioned to a first lateral side of the contact bridge.

2 more elements

Dependencies are inferred from the claim text.

Contact bridge with blow magnets

Life of this patent

Contact bridge with blow magnets

Life of this patent

Abstract

Claims12