Circuitry for portable lighting devices and portable rechargeable electronic devices
US7609005B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 7, 2006 |
| Grant date | Oct 27, 2009 |
| Priority date | — |
| Expiry date | Sep 7, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/007182
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A portable rechargeable electronic device, such as a flashlight, with external charging contacts and a short protection circuit is disclosed. The short protection circuit electrically uncouples one of the exposed charging contacts from the rechargeable power supply for the device when the charging contacts are short circuited. The charging contact is uncoupled without opening the power circuit for the device; thus, the device can continue to operate while the charging contacts are shorted. The power supply for the device may be a rechargeable lithium-ion battery pack. A flashlight with a circuit for reducing the initial surge of current that is sent through the lamp filament when a flashlight is turned on is also provided. The circuit reduces the stresses placed on the lamp bulb when it is turned on, thereby extending the life expectancy of the lamp bulb. A flashlight with an electronic switch is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.