Aspirated smoke detector with improved optical chamber

Patent metadata

Field	Value
Publication number	US-9824564-B2
Application number	US-201514968136-A
Country	US
Kind code	B2
Filing date	Dec 14, 2015
Priority date	Dec 14, 2015
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

An aspirated smoke detector with an improved optical chamber is provided. The aspirated smoke detector can include a base, an optical block housed within the base, the optical block housing an emitter and a receiver, and a chamber cover disposed over the base and the optical block to form an optical chamber therebetween. The chamber cover can capture light emitted by the emitter and reflect the captured light within the chamber cover while avoiding multiple back reflections of the captured light.

First claim

What is claimed is:

1. An aspirated smoke detector comprising: a base;
an optical block housed within the base, the optical block housing an emitter and a receiver; and
a chamber cover disposed over the base and the optical block to form an optical chamber therebetween,
wherein the chamber cover captures light emitted by the emitter and reflects the light captured by the chamber cover within the chamber cover while avoiding multiple back reflections of the light captured by the chamber cover,
wherein the chamber cover includes a plurality of varying shape sector members disposed on an outer concentric ring of the chamber cover and extending into the optical chamber,
wherein first respective ones of the plurality of varying shape sector members having a first shape are arranged relative to second respective ones of the plurality of varying shape sector members having a second shape so as to form a plurality of angled corridors therebetween, and
wherein each of the plurality of varying shape sector members is symmetrical.

2. The aspirated smoke detector of claim 1 wherein the light emitted by the emitter and received by the receiver fails to pass through a mirror or a lens.

3. The aspirated smoke detector as in claim 1 wherein the chamber cover is symmetrical.

4. The aspirated smoke detector as in claim 1 wherein each of the plurality of varying shape sector members directs the light captured by the chamber cover into a respective angled corridor of the plurality of angled corridors.

5. The aspirated smoke detector as in claim 1 wherein the plurality of varying shape sector members form a repeating pattern of shapes on the outer concentric ring.

6. The aspirated smoke detector as in claim 1 wherein the chamber cover reflects the light emitted by the emitter into the optical chamber in a repeatable manner.

7. The aspirated smoke detector as in claim 1 wherein the chamber cover includes an inner concentric ring, and wherein a plurality of ribs traverse the inner concentric ring and attenuate light reflection within the optical chamber.

8. A chamber cover for an optical chamber of an aspirated smoke detector comprising:
an annular disc that includes an outer concentric ring and an inner concentric ring;
a plurality of ribs traversing the inner concentric ring; and
a plurality of varying shape sector members protruding from a first side of the outer concentric ring,
wherein first respective ones of the plurality of varying shape sector members having a first shape are arranged relative to second respective ones of the plurality of varying shape sector members having a second shape so as to form a plurality of angled corridors therebetween, and
wherein each of the annular disc, the plurality of ribs, and the plurality of varying shape sector members is symmetrical.

9. The chamber cover of claim 8 wherein the plurality of varying shape sector members form a repeating pattern of shapes on the outer concentric ring.

10. The chamber cover of claim 8 wherein at least one of the annular disc, the plurality of ribs, and the plurality of varying shape sector members comprises plastic.

11. A method comprising:
an emitter emitting light into an optical chamber of an aspirated smoke detector;
a chamber cover capturing a first portion of the light emitted by the emitter; and
the chamber cover reflecting the first portion of the light within the chamber cover while avoiding multiple back reflections of the first portion of the light,
wherein the chamber cover reflecting the first portion of the light within the chamber cover includes a plurality of varying shape sector members of the chamber cover directing the first portion of the light into respective ones of angled corridors formed between differently shaped members of the plurality of varying shape sector members, and
wherein each of the plurality of varying shape sector members is symmetrical.

12. The method of claim 11 further comprising the chamber cover reflecting a second portion of the light emitted by the emitter into the optical chamber in a repeatable manner.

13. The method of claim 12 further comprising a receiver receiving the second portion of the light reflected by the chamber cover.

Assignees

• Honeywell Int Inc

Inventors

• Bressanutti Massimo
• Miheli Mauro
• Petronio Dino

Classifications

• G01N21/39

  using tunable lasers · CPC title

• G01N21/01

  Arrangements or apparatus for facilitating the optical investigation · CPC title

• G08B17/107 Primary

  for detecting light-scattering due to smoke · CPC title

• G01N2021/0112

  Apparatus in one mechanical, optical or electronic block · CPC title

• G01N21/00 Primary

  Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light (G01N3/00 - G01N19/00 take precedence) · CPC title