US3881420A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Smoke cord
Assignee: Ensign Bickford Co
•
Filing: 1973-07-13
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Granted: 1975-05-06
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Expires: 1993-07-13
Abstract
Abstract A smoke and fume producing device is provided in the form of a continuous elongated cord. The cord consists of a central igniter stem surrounded by the main pyrotechnic smoke charge and suitable outer coverings. The smoke charge preferably consists of a mixture of zinc oxide, a perchlorate oxidizer and a plasticized polyvinyl chloride resin and burns without flaming at a temperature of about 500*C.
Inventors
- 👤 John Mitchell Smith
- 👤 Hector Joseph Zilcosky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:15
CPC Classifications
F; F42; F42B; F42B3/00; F42B3/28; C; C06; C06B; C06B45/00; C06D; C06D3/00; C06D7/00; F42B12/00; F42B12/02; F42B12/36; F42B12/46; F42B12/48; Y; Y10; Y10S; Y10S149/00; Y10S149/117
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
179 words
In a pyrotechnic fume generating cord having substantial flexibility and a length to diameter ratio of at least about 50: 1, said cord being adapted to be coiled and spliced and comprising an elongated igniter stem extending along the length of the cord, a fume generating pyrotechnic charge in abutting relationship with said stem along its length and capable of being ignited by said igniter stem and a covering circumscribably confining both said charge and said stem along the length thereof, the combination wherein said pyrotechnic charge is a flameless smoke generating charge, said igniter stem is an incendiary composition encased within said charge and adapted to progressively burn with a short flame zone for initiating confined combustion of said flameless smoke generating charge without rupturing said covering and said covering includes a yarn wrapping and an outer plastic sheath exhibiting sufficient structural integrity to provide limited confined flameless combustion of said charge and to promote complete combustion of said charge and improved smoke generation, said cord having a combustion time of up to about 20 feet per second.
Claim 2
Dependent Claim
179 words
In a pyrotechnic fume generating cord having substantial flexibility and a length to diameter ratio of at least about 50: 1, said cord being adapted to be coiled and spliced and comprising an elongated igniter stem extending along the length of the cord, a fume generating pyrotechnic charge in abutting relationship with said stem along its length and capable of being ignited by said igniter stem and a covering circumscribably confining both said charge and said stem along the length thereof, the combination wherein said pyrotechnic charge is a flameless smoke generating charge, said igniter stem is an incendiary composition encased within said charge and adapted to progressively burn with a short flame zone for initiating confined combustion of said flameless smoke generating charge without rupturing said covering and said covering includes a yarn wrapping and an outer plastic sheath exhibiting sufficient structural integrity to provide limited confined flameless combustion of said charge and to promote complete combustion of said charge and improved smoke generation, said cord having a combustion time of up to about 20 feet per second.
Claim 3
Dependent Claim
40 words
The cord of claim 1 wherein the flameless smoke generating charge includes a smoke producing mixture comprising about 10 to 60 percent by weight of a plasticized halogencontaining vinyl polymer and up to 40 percent by weight of zinc oxide.
Claim 4
Dependent Claim
44 words
The cord of claim 1 wherein the flameless smoke generating charge is a granular material comprised of plasticized polyvinyl chloride, zinc oxide and perchlorate oxidizer in substantially equal proportions, the charge being Capable of flameless smoke generating combustion at temperatures well below 1,000* C.
Claim 5
Dependent Claim
72 words
The cord of claim 1 wherein the flameless smoke generating charge includes a smoke producing material comprising about 10 to 60 percent by weight of a plasticized high molecular weight homopolymer of vinyl chloride having an inherent viscosity of about 1.2 and at least 15 percent by weight of zinc oxide, said charge generating large volume of smoke upon ignition and exhibiting flameless combustion at a combustion temperature of about 350*-500* C.
Claim 6
Dependent Claim
40 words
The cord of claim 1 wherein the flameless smoke generating charge comprises about 50 to 80 percent by weight of a flameless smoke generating composition and about 20 to 50 percent by weight of an agent dispersed with the smoke.
Claim 7
Dependent Claim
17 words
The cord of claim 5 wherein the agent dispersed with the smoke is a riot control agent.
Claim 8
Dependent Claim
23 words
The cord of claim 1 wherein the igniter stem comprises a metal oxide incendiary mixture and forms a continuous core of the cord.
Claim 9
Dependent Claim
21 words
The cord of claim 1 including a dispersible agent adapted to be dispersed as part of the flameless smoke generating charge.
References Cited (Backward Citations)
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US3052577A
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US3320881A
Cited
US3467558A
Cited
US3724382A
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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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |