Apparatus for detect missing battery in smoke detector
US4959640A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 1989 |
| Grant date | Sep 25, 1990 |
| Priority date | — |
| Expiry date | Mar 9, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B29/181
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A battery-powered smoke detector in which the battery is inserted in a removable door that is then inserted into the detector to power the detector is rendered incapable of insertion into the smoke detector unless a battery is in place in the removable door. A spring-loaded door stop is moved by the spring into a position where it prevents the door from being inserted into the smoke detector. A pin in the female terminal of the door that engages the male terminal of the battery is forced away from the door stop by a spring. When the door stop is depressed manually and a battery is inserted into the terminals, the pin is forced by the male terminal of the battery into a latching position in the door stop, holding it in a position where it will not interfere with insertion of the door. The absence of a door provides warning to an observer that the battery-powered smoke detector is not operable for lack of a battery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.