Method for detecting fires

US6856252B2 · kind B2 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Anton Pfefferseder · Oberhaching, DE
• Bernd Siber · Glonn, DE
• Andreas Hensel · Egmating, DE
• Ulrich Oppelt · Zorneding, DE

Key dates

• Filing date: Feb 5, 2002
• Grant date: Feb 15, 2005
• Expiry date: Feb 26, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G08B29/20
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A method for detecting fires is proposed that serves to avoid false alarms, by providing that an alarm threshold is determined as a function of signal parameters derived from at least one sensor signal. False alarms are thus advantageously precluded. This is still further improved by setting up an alarm interval for which the alarm threshold must be exceeded, if an alarm is to be indicated. The alarm interval can also be determined adaptively as a function of the signal parameters. An upper threshold and a lower threshold are provided for the alarm interval and the alarm threshold, respectively, in order to build in a certain safety, so that the alarm threshold and alarm interval will not assume values that put a function of the fire detector at risk. It is also possible to use more sensor signals, in which case signal parameters can be generated by linking the sensor signals. As the fire detector, a scattered light smoke detector is preferably used, which is equipped with a labyrinth and a measurement chamber.