Unitized motor starter
US3987382A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1975 |
| Grant date | Oct 19, 1976 |
| Priority date | — |
| Expiry date | Jul 22, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H89/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A unitized combination motor starter is provided with a single insulated housing wherein a plurality of pole units are disposed side-by-side. Each pole unit includes a circuit breaker contact section and a contactor contact section. A spring powered mechanism for circuit breaker operation is disposed on one side of the pole units and an electromagnet for contactor operation is disposed on the other side of the pole units. The current carrying elements of each pole unit are arranged to provide a current loop having relatively close opposing arms so that large mechanical forces accompany high magnitude current flow. These forces are directed so as to produce a blow-off effect at the circuit breaker contacts, resulting in current limiting action to protect the contactor contacts. A removable and replaceable overload sensing electromagnet is provided for each of the pole units, and the coils thereof are of relatively high impedance to act as a current limiter during short circuit conditions to thereby protect heaters of overload relays connected in series with the unitized combination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.