Cooled electric fuse
US4041434A · kind A · utility
Inventors
Key dates
| Filing date | Jul 26, 1976 |
| Grant date | Aug 9, 1977 |
| Priority date | — |
| Expiry date | Jul 26, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H85/47
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In fuses embodying this invention each of the terminal elements has a port for the passage of fluid through the casing of the fuse during normal operation thereof, i.e. while the fuse is carrying current. A tubular fusible element conductively interconnects said port in each of said terminal elements. The fuse further includes a toroidal body of quartz sand filling the space between said casing and said tubular fusible element. The fusible element has perforations covered by annular structures of electric insulating material precluding said quartz sand from penetrating into said tubular fusible element during the normal operation of said fuse. The fuse is further provided with a pair of check valves which open during normal operation of said fuse and then allow the flow of fluid through said tubular fusible element and close on occurrence of a build-up of a predetermined amount of pressure inside of said tubular fusible element and then inhibit said flow of fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.