Patent US3916209A successfully refreshed from Google Patents.
US3916209A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vaned baffle for optical smoke detector
Assignee: SENTROL, INC. A CORP. OF OREGON
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Filing: 1974-04-08
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Granted: 1975-10-28
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Expires: 1994-04-08
Abstract
Abstract An optical smoke detector comprises split optical block mounting an exciter lamp and a smoke sensing photocell in two passages directed toward an intersection zone in a dark chamber formed by one side of the block, a base with a bottom and side wall and a cover, all secured together by one screw. A light pipe from the lamp extends outside the cover to indicate lamp operation. A second photocell is in a third passage communicating with the lamp passage, the third passage mounting diffuser and pin hole apertured disks for spreading a controlled light intensity over the second photocell. The optical block assembly includes an alarm circuit board operationally connected to the photocells and physically positioning the block on the base. Smoke enters the dark chamber through passages formed by curved, light obstructing vanes converging toward an opening to the chamber between the opening and a baffle.
Inventors
- 👤 Donald F Steele
- 👤 Robert B Enemark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:49
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B17/103; G08B17/107; G08B17/11; G08B17/113
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
159 words
A smoke detector for ceiling mounting comprising: walls forming a dark chamber, one wall having an opening having a vertical axis, a light source directed into the chamber, a photoelectric cell detecting light scattered from particles in a zone of the light, a horizontal light baffle spaced outside and light-shielding said opening and defining a horizontal space allowing unimpeded horizontal smoke flow into the space, and a plurality of vanes between the baffle and said one wall leading horizontally toward the space between the baffle and opening, at least two of the vanes being curved convergently toward the opening to form at least one horizontal passage increasingly converging toward said opening, the increasing convergence of the passage accelerating the smoke, and the curvature imparting horizontal eddying motion to the smoke as it turns from horizontal flow between the vanes and enters the dark chamber vertically through the opening, thereby to promote movement of the smoke into the light zone.
Claim 2
Dependent Claim
159 words
A smoke detector for ceiling mounting comprising: walls forming a dark chamber, one wall having an opening having a vertical axis, a light source directed into the chamber, a photoelectric cell detecting light scattered from particles in a zone of the light, a horizontal light baffle spaced outside and light-shielding said opening and defining a horizontal space allowing unimpeded horizontal smoke flow into the space, and a plurality of vanes between the baffle and said one wall leading horizontally toward the space between the baffle and opening, at least two of the vanes being curved convergently toward the opening to form at least one horizontal passage increasingly converging toward said opening, the increasing convergence of the passage accelerating the smoke, and the curvature imparting horizontal eddying motion to the smoke as it turns from horizontal flow between the vanes and enters the dark chamber vertically through the opening, thereby to promote movement of the smoke into the light zone.
Claim 3
Dependent Claim
19 words
A detector according to claim 1 wherein the curvature of the vanes obstructs direct light rays from the opening.
Claim 4
Dependent Claim
21 words
A detector according to claim 1 wherein the vanes are gradually curved to minimize air friction or turbulence in the passage.
Claim 5
Dependent Claim
22 words
A detector according to claim 1 wherein the vanes form entrances to a plurality of passages throughout more than 180* of angle.
Claim 6
Dependent Claim
16 words
A detector according to claim 4 wherein the vane entrances extend throughout substantially 360* of angle.
Claim 7
Dependent Claim
30 words
A detector according to claim 1 wherein the vanes form an entrance to and an exit from the passage, the exit being disposed at the chamber opening and communicating therewith.
Claim 8
Dependent Claim
24 words
A detector according to claim 1 wherein the chamber opening is adjacent to the light scattering zone and the vanes converge toward the opening.
Claim 9
Dependent Claim
14 words
A detector according to claim 7 wherein the vanes extend laterally of the opening.
Claim 10
Dependent Claim
45 words
A detector according to claim 7 wherein the vanes are disposed in trios, the outer two vanes of the trio having a junction at the opening, and the intermediate vane terminating short of the junction to form an air passage between the termination and junction.
Claim 11
Dependent Claim
17 words
A detector according to claim 1 wherein the chamber walls form a second opening to the chamber.
Claim 12
Dependent Claim
20 words
A detector according to claim 1 wherein the light baffle and vanes form a unitary structure detachable from the chamber.
Claim 13
Dependent Claim
40 words
A detector according to claim 1 wherein a ring has a lip encircling the opening to the chamber, and the vanes extend from the opening beyond the lip so as to provide access to the passage unobstructed by the lip.
Claim 14
Dependent Claim
24 words
A detector according to claim 4 wherein at least two vanes converge to a junction deflecting air through the opening into the dark chamber.
Claim 15
Dependent Claim
31 words
A detector according to claim 13 wherein said junction extends across the convergent end of another passage thereby to obstruct air flow past the chamber opening and out an opposed passage.
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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) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |