US4034676A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inhibitor coating for solid rocket propellent charge
Assignee: Rheinmetall Air Defence AG
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Filing: 1975-06-16
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Granted: 1977-07-12
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Expires: 1995-06-16
Abstract
Abstract An inhibitor coating for a solid propellant charge for protecting against undesired burning-off, comprising: A. an insulating layer containing a binder and a filler, and B. a protective- and adhesion layer located between the insulating layer and the propellant charge; C. the binder consisting of a castable mass which has poor smoke developing properties; D. the filler consisting of a fine granular cooling agent possessing good packability; and E. the protective- and adhesion layer consisting of a completely set polyisocyanate forming a barrier against plasticizer migration.
Inventors
- 👤 Eduard Daume
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:59
CPC Classifications
C; C06; C06B; C06B45/00; C06B45/12; C06B21/00; C06B21/0008; C06B21/0025; Y; Y10; Y10S; Y10S102/00; Y10S102/704
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
129 words
The combination of an inhibitor coating and a solid double base propellant charge comprising: a. a polyurethane protective- and adhesion layer consisting essentially of a lowmolecular weight triisocyanate applied to the propellant charge; b. a castable insulating layer for protecting said propellant charge against undesired burning-off applied to said protective- and adhesion layer and comprising: (i) a binder of polyurethane, (ii) a fine granular cooling agent as filler; c. said polyurethane of the insulating layer being different from the polyurethane of said protective- and adhesion layer and possessing poor smoke developing properties; d. said filler containing aluminium hydroxide and possessing good packability; e. said protective- and adhesion layer being completely moisture hardened by atmospheric moisture before the application of the insulating layer and forming a barrier against plasticizer migration.
Claim 2
Dependent Claim
129 words
The combination of an inhibitor coating and a solid double base propellant charge comprising: a. a polyurethane protective- and adhesion layer consisting essentially of a lowmolecular weight triisocyanate applied to the propellant charge; b. a castable insulating layer for protecting said propellant charge against undesired burning-off applied to said protective- and adhesion layer and comprising: (i) a binder of polyurethane, (ii) a fine granular cooling agent as filler; c. said polyurethane of the insulating layer being different from the polyurethane of said protective- and adhesion layer and possessing poor smoke developing properties; d. said filler containing aluminium hydroxide and possessing good packability; e. said protective- and adhesion layer being completely moisture hardened by atmospheric moisture before the application of the insulating layer and forming a barrier against plasticizer migration.
Claim 3
Dependent Claim
69 words
The combination as defined in claim 1, wherein the cooling agent has a grain size less than 150 microns, and the grain size is adjusted such that there is attained a packability of at least 55 percent by volume, the packability being designated by the symbol P which is the quotient of the solid density ρ in grams/cm 3 and the density ρ R in grams/cm 3 wherein ##EQU2##
Claim 4
Dependent Claim
33 words
The combination as defined in claim 1, wherein the binder of the insulating layer is cross-linked with diamine and additionally with castor oil in that the diamine is partially replaced by castor oil.
Claim 5
Dependent Claim
16 words
The combination as defined in claim 1, wherein the binder contains a plasticizer of acetyltri-n-butyl citrate.
Claim 6
Dependent Claim
22 words
The combination as defined in claim 2, wherein the grain size of the fine granular cooling agent is less than 150 microns.
References Cited (Backward Citations)
US3144830A
Cited
US3529042A
Cited
US3447980A
Cited
US3716604A
Cited
US3682727A
Cited
US3554820A
Cited
US3813308A
Cited
US3855176A
Cited
US3714047A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-11 | 1981-01-10 | 1981-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-11 | 1985-01-10 | 1985-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-11 | 1989-01-10 | 1989-07-12 | $7700.00 | Window Closed / Lapsed |