Scattered light smoke alarm

• US 20020153499A1
• Filed: 04/09/2002
• Published: 10/24/2002
• Est. Priority Date: 04/19/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Oppelt, Ulrich, Siber, Bernd, Hensel, Andreas, Pfefferseder, Anton
• Granted Patent: US 6,828,913 B2
• Time in Patent Office: Days
• US Class Current: 250/559.16
• CPC Class Codes: G01V 8/12 using one transmitter and one receiver
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers
• CPC Class Codes: G08B 17/107 for detecting light-scattering due to smoke

Abstract

A dispersion light smoke detector has a structure for providing a definite measuring volume, the structure being formed as two light receivers or an imaging optical system for one light receiver.

Claims

1. A dispersion light smoke detector, comprising means for providing a definite measuring volume, said means being formed as means selected from the group consisting of two light receivers, and an imaging optical system for one light receiver.

2. A dispersion light smoke detector as defined in claim 1, wherein each of said light receivers is formed as a detector cell.

3. A dispersion light smoke detector as defined in claim 1, wherein each of said light receivers is formed as a detector array.

4. A dispersion light smoke detector as defined in claim 1, wherein each of said light receivers has two detector cells which are arranged perpendicular to one another for a two-dimensional tracking of a measuring object.

5. A dispersion light smoke detector as defined in claim 1, wherein said two light receivers have each an element selected from the group consisting of a detector cell and a detector array;

and further comprising a processor which is connected with said at least one element and is operative for determining a parameter of a measuring object selected from the group consisting of a distance, a speed, and both, from signals of said two light receivers.

6. A dispersion light smoke detector as defined in claim 5, wherein said processor is formed so as to evaluate contours of the measuring object for distinguishing between smoke and another object.