Overload protector for a telephone set
US4486804A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1983 |
| Grant date | Dec 4, 1984 |
| Priority date | — |
| Expiry date | Mar 30, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/176
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An overload protector for a telephone set or other telecommunications terminal comprises an electrical component having DC continuity and DC resistance mounted by leads on a circuit board, the leads soldered to the conductor pattern. A compression spring is positioned on each lead, held in compression between component and circuit board. An insulating member fits around the component. In application of an overload, the component heats up to a level at which sufficient heat travels down the leads to melt the solder. Usually both leads become unsoldered. A convenient component is a carbon block resistor, in the Tip or Ring line. The insulating member would be a sleeve loosely fitting over the resistor and retaining heat in the resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.