Reduced gain thrust control valve
View Patent ↗A reduced gain thrust control valve for use in a rocket engine has a housing with a fluid inlet and a piston and cylinder unit for controlling a fluid output of the control valve. The fluid inlet is formed by at least one metering element formed in the housing. The at least one metering element has a rectangular portion for producing improved control stability, a tee and slot portion for controlling thrust during a start transient engine phase, and a fixed turbine bypass portion for accommodating a retainer. The retainer incorporates at least one fluid channel so as to produce repeatable fixed bypass flow metering.
1. A reduced gain thrust control valve for use in a rocket engine comprising:
a housing having a fluid inlet;
said fluid inlet having at least one metering element formed therein;
said at least one metering element comprising first means for producing improved control stability, second means for controlling thrust during a start transient engine phase, and third means for accommodating a retainer; and
a piston and cylinder unit for controlling a fluid output of said control valve.
2. A reduced gain thrust control valve according to claim 1 , wherein said at least one metering element is machined into said housing.
3. A reduced gain thrust control valve according to claim 1 , wherein said housing has a plurality of said metering elements machined therein.
4. A reduced gain thrust control valve according to claim 1 , wherein said first means comprises a rectangular portion.
5. A reduced gain thrust control valve according to claim 1 , wherein said second means comprises a tee and slot portion.
6. A reduced gain thrust control valve according to claim 1 , wherein said third means comprises a fixed turbine bypass portion.
7. A reduced gain thrust control valve according to claim 1 , wherein said fixed turbine bypass portion is always uncovered and used to compensate for engine to engine variations.
8. A reduced gain thrust control valve according to claim 1 , further comprising:
said housing having an opening and said retainer being positioned within said opening; and
said retainer having at least one fluid channel therein.
9. A reduced gain thrust control valve according to claim 1 , wherein said piston and cylinder unit comprises a piston and a cylinder which move axially with respect to said housing.
10. A reduced gain thrust control valve according to claim 8 , wherein said piston and cylinder unit covers and uncovers said first and second means of said at least one metering element.
11. A metering element for use in a reduced gain thrust control valve for an engine comprising:
a rectangular portion for providing control stability margin and a steady state operating range for said engine;
a tee and slot portion for controlling thrust during an engine start transient;
a fixed turbine bypass portion; and
said fixed turbine bypass portion accommodating a retainer having at least one fluid channel so as to produce repeatable fixed bypass flow metering.