Patent US3914935A successfully refreshed from Google Patents.
US3914935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual area nozzle
Assignee: Boeing North American Inc
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Filing: 1971-03-01
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Granted: 1975-10-28
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Expires: 1991-03-01
Abstract
Abstract A boost-sustain solid rocket system having boost and sustain grains in the rocket casing with a fixed nozzle and a movable nozzle, which is operable in response to a pressure drop to a predetermined level in the combustion chamber resultant during burn-out of the boost grain, to block a portion of the throat areas of said nozzles and increase the combustion chamber pressure during burning of the sustain grain.
Inventors
- 👤 Jr William M Burkes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:14
CPC Classifications
F; F02; F02K; F02K9/00; F02K9/80; F02K9/86
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
221 words
A solid rocket system comprising a rocket casing, solid propellant boost and sustain grains in said casing, a combustion chamber and a rocket nozzle, said rocket nozzle being connected to the exit end of said combustion chamber and comprising a first convergent-divergent nozzle portion having a minimum throat area, a second convergent-divergent nozzle portion having an additional throat area, a solid annular plug means spaced from the interior periphery of said combustion chamber in juxtaposition to said second convergent-divergent nozzle portion in a first position so as to effectively allow flow of exhaust gases through both of said nozzle portions during boost phase operation, and means including at least one axially extending translatable rod fixed to said plug means to move said plug means translationally into a second fixed position blocking all of the additional throat area of said second convergent-divergent nozzle portion during a sustain phase operation so as to decrease the total effective throat area of the overall nozzle and to allow flow of exiting gases through only said first nozzle portion, said means to move said plug means being in direct communication to said combustion chamber during all phases of operation and being operable only in response to a pressure drop to a lower predetermined pressure level in said combustion chamber during burnout of one of said grains.
Claim 2
Dependent Claim
221 words
A solid rocket system comprising a rocket casing, solid propellant boost and sustain grains in said casing, a combustion chamber and a rocket nozzle, said rocket nozzle being connected to the exit end of said combustion chamber and comprising a first convergent-divergent nozzle portion having a minimum throat area, a second convergent-divergent nozzle portion having an additional throat area, a solid annular plug means spaced from the interior periphery of said combustion chamber in juxtaposition to said second convergent-divergent nozzle portion in a first position so as to effectively allow flow of exhaust gases through both of said nozzle portions during boost phase operation, and means including at least one axially extending translatable rod fixed to said plug means to move said plug means translationally into a second fixed position blocking all of the additional throat area of said second convergent-divergent nozzle portion during a sustain phase operation so as to decrease the total effective throat area of the overall nozzle and to allow flow of exiting gases through only said first nozzle portion, said means to move said plug means being in direct communication to said combustion chamber during all phases of operation and being operable only in response to a pressure drop to a lower predetermined pressure level in said combustion chamber during burnout of one of said grains.
Claim 3
Dependent Claim
54 words
The invention as set forth in claim 1 in which said first nozzle portion comprises means forming a central convergent-divergent aperture in said annular plug means and said means to move said plug means is responsive to a pressure drop to a predetermined level in said combustion chamber during burnout of said boost grain.
Claim 4
Dependent Claim
85 words
The invention as set forth in claim 1 in which said first nozzle portion is centrally contained in said plug means and said plug means translatable rod has at least one fixed piston portion extending rearwardly therefrom into a reservoir formed within a surrounding support for said second nozzle portion, a pressure sensing port in said combustion chamber cooperating with said rod and said reservoir, to actuate said plug means into blocking position when the pressure in said combustion chamber drops to said predetermined level.
Claim 5
Dependent Claim
49 words
The invention as set forth in claim 3 in which said reservoir contains a hydraulic fluid and said pressure port is in flow communication with a diaphragm-operated valve for releasing hydraulic fluid from said reservoir to permit movement of said rod and said plug means into said blocking position.
Claim 6
Dependent Claim
95 words
A nozzle for disposition at the downstream exit end of a thrust-producing device comprising: an outer housing for receiving the combustion gases of said device, an inner annular wall portion peripherally formed on said housing, said wall portion forming a convergent-divergent passage for exhaust gases, wherein the point of greatest convergence forms a fIrst throat area, a rigidly affixed hollow body disposed in said first throat area, said body containing a second throat area formed concentrically therein, means for selectively controlling at least a portion of the exhaust gas flowing though said first throat area.
Claim 7
Dependent Claim
95 words
A nozzle for disposition at the downstream exit end of a thrust-producing device comprising: an outer housing for receiving the combustion gases of said device, an inner annular wall portion peripherally formed on said housing, said wall portion forming a convergent-divergent passage for exhaust gases, wherein the point of greatest convergence forms a fIrst throat area, a rigidly affixed hollow body disposed in said first throat area, said body containing a second throat area formed concentrically therein, means for selectively controlling at least a portion of the exhaust gas flowing though said first throat area.
Claim 8
Dependent Claim
60 words
The nozzle of claim 5 wherein said means for selectively controlling at least a portion of the gas through said first throat area comprises an axially movable annular ring disposed upstream from said wall portion, said ring provided with a downstream portion of seating against the upstream surfaces of both said wall portion and said body in the closed position.
Claim 9
Dependent Claim
13 words
The nozzle of claim 6 further comprising means for moving said annular ring.
Claim 10
Dependent Claim
34 words
The nozzle of claim 6 further comprising means on the mating surfaces of said ring, said wall portion and said body for effecting a seal therebetween when said ring is in a closed position.
References Cited (Backward Citations)
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 |