Overload protected solid state varistors
US6094128A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 11, 1998 |
| Grant date | Jul 25, 2000 |
| Priority date | — |
| Expiry date | Aug 11, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01C7/126
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A fail-safe varistor includes either a fail-short or a fail-open device. Both devices include a fusible, electrically conductive material that melts before the varistor fails due to overvoltage. In the fail-open device, the fusible, electrically conductive material joins separated portions of the leads. The material also may join at least one of the leads directly to a ceramic disk of the varistor. Upon reaching the predetermined temperature, the varistor melts causing a circuit including the varistor to open. In the fail-short device, the material melts creating a short between the leads. This short causes a fuse or a breaker to open the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.