Molded case circuit breaker with improved high fault current interruption capability
US4470027A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 1982 |
| Grant date | Sep 4, 1984 |
| Priority date | — |
| Expiry date | Jul 16, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H71/504
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A contact structure (40, 44; 62, 63) is arranged to provide oppositely directed parallel current paths within a closed loop magnetic flux amplifier (46) to be directly separable under high overload current conditions, the flux amplifier (46) functioning to arrest the movable contact (62, 63) momentum. Manufacturing economies are realized by subassembling the stationary contact structure (40, 42, 44) and flux amplifier (46) and subsequently trapping one end (42a) of that assembly within the base (4a) and securing the other end with a single screw (68). The movable contact arm (62) comprises a plurality of blanked laminations assembled to provide improved contact (63) mounting and bearing (62d) surfaces. The molded case sidewalls are strengthened in the contact separation area by offsetting the parting line (PL) between cover (6) and base (4) closer to the bottom of base (4) and overlapping the thinner base sidewalls with thicker cover sidewalls at the offset (4e, 6e).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.