Variable aperture annular nozzle for rocket motor igniter
AssigneeThiokol Corporation
InventorFrank H. Bell
Life of this patent
Estimating the term…
Abstract
A single port rocket motor igniter nozzle features an adjustable throat or annulus that is formed by a tapered flange and an opening in an igniter body that contains a propellant charge, the position of the flange relative to the opening being adjustable to vary the throat area by a calibrated central shaft. The igniter allows rapid evaluation of propellant grain designs and nozzle throat areas, and as a result, enables the faster development and assembly of a less expensive igniter that is operative to produce at optimum pressure and burning rate, and to effectively propagate, the high temperature gases that are needed for rocket motor propellant ignition.
Claims12
An ignition device comprising
- a body forming a combustion chamber having oppositely disposed first and second openings in the wall thereof, at least the second of said openings being generally circular,
- an insulation coating on the wall of the chamber between the chamber wall first and second openings,
- a propellant charge having an axial bore and substantially filling the coated portion of the chamber wall with the bore of the charge extending longitudinally between the chamber wall first and second openings,
- a shaft having a first end and a second end, said shaft extending in sealing manner through the first opening in the wall of the chamber and through the bore of said charge with the second end thereof in position adjacent the second opening in the chamber wall, and
- a plug supported by the second end of said shaft adjacent the second chamber wall opening, said plug having an annular flange that diverges outwardly with respect to the second chamber wall opening thereby forming an annular aperture the area of which is predetermined in accordance with the adjusted position of said shaft within the chamber.
Dependencies are inferred from the claim text.