US4430646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Forward scatter smoke detector
Assignee: Sentrol Inc A Corp Of Oregon
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Filing: 1980-12-31
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Granted: 1984-02-07
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Expires: 2000-12-31
Abstract
Abstract An optical smoke detector having a conical masking body located directly between a light source and a light receiver. The masking body is provided with a reflecting surface so that rays from the light source are diverted into a reaction zone to supplement direct rays from the light source to the zone. In one embodiment the reflecting surface is cuspidate while in another embodiment a second masking body is added which shadows the light receiver from viewing the base of the first masking body.
Inventors
- 👤 Robert B. Enemark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:52
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/49; G01N21/53; G01N2201/00; G01N2201/06; G01N2201/064; G01N2201/0642
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
131 words
A particle detector comprising: a source of light directed on a first path accessible to particles; a photocell having a photosensitive area viewing on a second path into a zone of intersection of the two paths and responsive to light scattered from particles in the zone; and a body masking direct light from the source to the photosensitive area and having a periphery outside which light passes to the intersection zone; wherein the detector includes a reflective surface disposed between the masking body periphery and the light source having reflective components at an angle relative to direct rays from the source toward the masking body such as to direct such rays away from the body into a substantial value of the intersection zone; and wherein the reflective surface is cone like.
Claim 2
Dependent Claim
131 words
A particle detector comprising: a source of light directed on a first path accessible to particles; a photocell having a photosensitive area viewing on a second path into a zone of intersection of the two paths and responsive to light scattered from particles in the zone; and a body masking direct light from the source to the photosensitive area and having a periphery outside which light passes to the intersection zone; wherein the detector includes a reflective surface disposed between the masking body periphery and the light source having reflective components at an angle relative to direct rays from the source toward the masking body such as to direct such rays away from the body into a substantial value of the intersection zone; and wherein the reflective surface is cone like.
Claim 3
Dependent Claim
16 words
A detector according to claim 1 wherein the reflective surface is a surface of axial revolution.
Claim 4
Dependent Claim
19 words
A detector according to claim 2 wherein the reflective surface is a surface of revolution of a curved line.
Claim 5
Dependent Claim
18 words
A detector according to claim 2 wherein the light source and photocell are on the axis of revolution.
Claim 6
Dependent Claim
27 words
A detector according to claim 1 wherein the surface has a conical apex directed toward the light source and the surface flares away from the light source.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-06 | 1987-08-08 | 1988-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-06 | 1991-08-08 | 1992-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-06 | 1995-08-08 | 1996-02-07 | $7700.00 | Window Closed / Lapsed |