Temperature responsive, electric overcurrent protection module
US5363083A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 11, 1993 |
| Grant date | Nov 8, 1994 |
| Priority date | — |
| Expiry date | Jun 11, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2085/0483
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A temperature responsive electric overcurrent protection module incorporated in an electric circuit on a circuitboard has a PTC resistor which heats up when subjected to an excessive current. Its resistance rises with its temperature to control the current and protect the circuit, including electric components thereof. To protect the circuit against occasionally encountered, large overcurrents, which could damage the circuits and/or cause a burn-out, a thermal switch or overcurrent fuse is provided which comprises an electrically and thermally conductive contact plate, and an associate thermal switch formed by a planar frame secured to the substrate and a spring arm protruding therefrom. The contact plate is spaced from the substrate, and a free end of the spring arm is secured to the contact plate with a heat responsive solder, thereby prestressing the spring arm so that, upon a melting of the solder due to an overheating of the contact plate by the PTC resistor, the spring arm automatically moves away from the contact plate, thereby opening the circuit and preventing damage to it from the excessive overcurrent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.