US3871173A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant chamber pressure throttling injector
Assignee: United States Department of the Navy
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Filing: 1970-03-24
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Granted: 1975-03-18
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Expires: 1990-03-24
Abstract
Abstract A rocket engine having an injector assembly consisting of a throttle piston and deflector plate, which varies the propellant flow rate, coupled to a central throat pintle, which simultaneously varies the throat area of the exhaust nozzle, in order to maintain a cosntant pressure in the combustion chamber for all degrees of throttling. As the injector throttle piston moves aft to reduce the propellant flow by reducing the area of the orifices through which both the fuel and oxidizer pass, the throat pintle moves forward to reduce the throat area of the nozzle. This joint movement of the throttle piston and throat pintle causes a thrust fall-off without any change in the combustion chamber pressure. The rocket engine also has a thrust chamber made of a composite design of materials which can withstand the high temperatures and pressures resulting from the combustion of higher energy propellants.
Inventors
- 👤 Ronald F Mckenna
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:23
CPC Classifications
F; F02; F02K; F02K9/00; F02K9/97; F02K9/42; F02K9/44; F02K9/52; F02K9/56; F02K9/58; F02K9/80; F02K9/86
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
129 words
A bipropellant rocket engine comprising an injector assembly and thrust chamber: said injector assembly including an axially moveable annular deflector plate having two annular concave deflector surfaces in the thrust chamber over which propellants flow and are formed into circumferential sheets, and a central pintle coaxially arranged in said thrust chamber and being formed partially of pyrolytic graphite in order to withstand the high temperatures and pressures of combustion; said thrust chamber including a combustion chamber and an exhaust nozzle; and means to actuate said deflector plate and said pintle to vary the thrust of the rocket engine by simultaneously varying the propellant flow rate and the throat area of said exhaust nozzle in order to maintain the pressure in the combustion chamber constant for all degrees of throttling.
Claim 2
Dependent Claim
129 words
A bipropellant rocket engine comprising an injector assembly and thrust chamber: said injector assembly including an axially moveable annular deflector plate having two annular concave deflector surfaces in the thrust chamber over which propellants flow and are formed into circumferential sheets, and a central pintle coaxially arranged in said thrust chamber and being formed partially of pyrolytic graphite in order to withstand the high temperatures and pressures of combustion; said thrust chamber including a combustion chamber and an exhaust nozzle; and means to actuate said deflector plate and said pintle to vary the thrust of the rocket engine by simultaneously varying the propellant flow rate and the throat area of said exhaust nozzle in order to maintain the pressure in the combustion chamber constant for all degrees of throttling.
Claim 3
Dependent Claim
63 words
A rocket engine according to claim 1 wherein: the wall structure of said thrust chamber is a composite structure formed of two inner layers of graphite base materials and an outer layer of a silica phenolic; and the centerbody of said pintle is formed of Columbium in order to withstand the high temperatures and pressures encountered in the combustion of high energy propellants.
Claim 4
Dependent Claim
56 words
A rocket engine according to claim 2 Wherein said injector assembly further includes circumferentially spaced fuel injection slots and oxidizer injection slots, each slot being rectangular in cross section, whereby as the deflector plate is actuated to decrease the propellant flow rate and partially cover said injection slots, a constant mixture ratio of propellants is maintained.
Claim 5
Dependent Claim
101 words
A rocket engine according to claim 3 wherein said actuation means include a cam gear and a plurality of guide posts, said cam gear having oppositely inclined ramps which actuate said guide posts forward and aft of the rocket engine, said guide posts being connected to said deflector plate and said throat pintle, whereby actuation of said guide posts by said cam gear moves said deflector plate and said throat pintle in opposite directions to simultaneously vary the propellant flow rate and throat area of the nozzle to maintain the pressure in the combustion chamber constant for all degrees of throttling.
Claim 6
Dependent Claim
166 words
A bipropellant rocket engine comprising an injector assembly and thrust chamber: said injector assembly consisting of an annular deflector plate over which propellants flow and are formed into circumferential sheets, and a central pintle coaxially arranged in said thrust chamber and being formed partially of pyrolytic graphite with a centerbody made of Columbium in order to withstand the high temperatures and pressures of combustion; said thrust chamber including a combustion chamber and exhaust nozzle, the wall structure of said thrust chamber being a composite structure formed of two inner layers of graphite base materials and an outer layer of a silica phenolic in order to withstand the high temperatures and pressures encountered in the combustion of high energy propellants; and means to actuate said deflector plate and said pintle to vary the thrust of the rocket engine by simultaneously varying the propellant flow rate and the throat area of said exhaust nozzle to maintain the pressure in the combustion chamber constant for all degrees of throttling.
Claim 7
Dependent Claim
166 words
A bipropellant rocket engine comprising an injector assembly and thrust chamber: said injector assembly consisting of an annular deflector plate over which propellants flow and are formed into circumferential sheets, and a central pintle coaxially arranged in said thrust chamber and being formed partially of pyrolytic graphite with a centerbody made of Columbium in order to withstand the high temperatures and pressures of combustion; said thrust chamber including a combustion chamber and exhaust nozzle, the wall structure of said thrust chamber being a composite structure formed of two inner layers of graphite base materials and an outer layer of a silica phenolic in order to withstand the high temperatures and pressures encountered in the combustion of high energy propellants; and means to actuate said deflector plate and said pintle to vary the thrust of the rocket engine by simultaneously varying the propellant flow rate and the throat area of said exhaust nozzle to maintain the pressure in the combustion chamber constant for all degrees of throttling.
Claim 8
Dependent Claim
80 words
A rocket engine according to claim 5 wherein: said injector assembly further includes two concave deflector surfaces formed on the face of said annular deflector plate over which propellants flow and are formed into circumferential sheets; and circumferentially spaced fuel injection slots and oxidizer injection slots, each slot being rectangular in cross section, whereby as the deflector plate is actuated to decrease the propellant flow rate and partially cover said injection slots, a constant mixture ratio of propellants is maintained.
Claim 9
Dependent Claim
101 words
A rocket engine according to claim 6 wherein said actuation means include a cam gear and a plurality of guide posts, said cam gear having oppositely inclined ramps which actuate said guide posts forward and aft of the rocket engine, said guide posts being connected to said deflector plate and said throat pintle, whereby actuation of said guide posts by said cam gear moves said deflector plate and said throat pintle in opposite directions to simultaneously vary the propellant flow rate and throat area of the nozzle to maintain the pressure in the combustion chamber constant for all degrees of throttling.
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) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |