초록 ▼

A convergent-divergent rocket nozzle is made to be extendible by moving successively larger, conic annuli into a tandem arrangement therewith, so that they collectively form a single exit cone. In a stowed position, the movable, conic annuli concentrically surround the primary nozzle. Each of these

A convergent-divergent rocket nozzle is made to be extendible by moving successively larger, conic annuli into a tandem arrangement therewith, so that they collectively form a single exit cone. In a stowed position, the movable, conic annuli concentrically surround the primary nozzle. Each of these movable segments of the nozzle is moved relative to its adjacent upstream segment by being attached to rotary means that engage elongated positive traction surfaces on a set of guide members that are spaced circumferentially about and fixed at each end to the upstream segment, parallel to the axis of the nozzle. The rotary means are actuated, by means of a flexible shaft, by a small, electric motor that is mounted to each movable segment. When in fully deployed position, each movable segment is locked in place by tang latches, fixed to the adjcent, upstream segment, that engage an internal flange or shoulder on the movable segment. Prior to deployment, the rotary means is disengaged from the positive traction surface of each guide member, and the tang latches, being outwardly spring biased, then function as deceleration means to slow the segment being deployed. An elastomeric ring is confined between flanges of each adjacent pair of nozzle segments, where it functions as a hot gas seal and as a shock absorber.

대표청구항 ▼

1. A nested extendible thrust nozzle for a rocket motor comprising; a plurality of nested nozzle segments, the inner one of said segments being attachable to a rocket motor case, and at least one outer segment being movable from a nested position relative to the inner segment to an extended, full

1. A nested extendible thrust nozzle for a rocket motor comprising; a plurality of nested nozzle segments, the inner one of said segments being attachable to a rocket motor case, and at least one outer segment being movable from a nested position relative to the inner segment to an extended, fully deployed position, said segments each having a divergent conic interior surface, which surfaces collectively form a single, substantially conic surface when said outer segment is in its fully deployed position; a set of elongated, stationary guide members fixed at each end to the exterior of said interior segment, each guide member of said set having an elongated positive traction surface that is disposed substantially parallel to the axis of the nozzle; and rotational traction means attached to said outer segment and engaging the traction surface of each of said guide members for moving said outer segment to its deployed position. 2. The nozzle of claim 1 further including means for actuating said rotational traction means. 3. The nozzle of claim 2 wherein the full extent of travel of said rotational traction means is greater than the length of said positive traction surface whereby mometum only moves said outer segment from the end of the positive traction surface to its fully deployed position. 4. The nozzle of claim 1 wherein said nozzle segments are longitudinal segments, said inner segment comprising a convergent-divergent thrust nozzle, and further including a plurality of outer segments, each of which outer segments is movable with respect to said inner segment to an individual, fully deployed position, and comprising successively larger, conic annuli the interior surfaces of which collectively form a single, substantially conic surface with the divergent portion of said inner segment when said outer segments are all deployed in adjoining, tandem arrangement, a set of elongated, stationary guide members fixed to the exterior of each of the segments to and including the penultimate outer segment, each guide member having a positive traction surface that is disposed substantially parallel to the axis of the nozzle; rotational traction means attached to each of the movable segments and engaging the traction surface of each guide member for moving its segment along the axis of the nozzle; and means for actuating the rotational traction means. 5. The nozzle of claim 4 wherein the positive traction surface on each guide member ends before the full extent of travel of the rotational traction means, so that only the momentum of each of the movable segments propels it from the end of the associated traction surfaces to its fully deployed position relative to the nozzle segment upstream thereof. 6. The nozzle of claim 5 wherein the guide members and their traction surfaces are screws and the rotational traction means is a threaded nut on each of the screws. 7. The nozzle of claim 6 wherein the screws and nuts have acme threads. 8. The nozzle of claim 5 wherein the guide members and their traction surfaces comprise rack gears and the rotational traction means is a pinion gear engaging each of the rack gears. 9. The nozzle of claim 8 further including roller bearings operatively attached to each pinion gear but bearing on flat portions of the rack gear. 10. The nozzle of claim 2 wherein the means for actuating the rotational traction means comprises: a flexible shaft; a first set of gears fixed to the flexible shaft, one said gear for each rotational traction means; a second set of gears, each gear fixed to one of said rotational traction means and engaging a gear of the first set, whereby the rotational traction means is actuated when the flexible shaft is rotated; a source of rotational power; and means for connecting the source of rotational power to the flexible shaft for rotation thereof. 11. The nozzle of claim 10 wherein the first and second sets of gears are worm gears. 12. The nozzle of claim 10 wherein the guide members and their traction surfaces are screws, the rotational traction means are threaded nuts on the screws, and the second set of gears comprises gear teeth formed on the periphery of each said nuts. 13. The nozzle of claim 10 wherein the source of rotational power is an electric motor. 14. The nozzle of claim 13 wherein the means for connecting the source of rotational power to the flexible shaft comprises a gear fixed to the armature shaft of the electric motor and a second gear engaged therewith and fixed to the flexible shaft. 15. The nozzle of claim 14 further including a plurality of housings, each housing enclosing one of said rotational traction means and the adjacent portions of its corresponding guide member and of the flexible shaft, and one of said housings enclosing the connection of the electric motor with the flexible shaft. 16. The nozzle of claim 15 further including protective tubes enclosing the flexible shaft between the housings. 17. The nozzle of claim 4 further including an annular array of tang latches fixed to the aft end portion of each nozzle segment to and including the penultimate segment, each tang latch being fixed at its forward end to its corresponding nozzle segment and spring biased outwardly therefrom; and an inwardly extending flange in the forward end portion of each of the movable nozzle segments that passes over the tang latches in frictional contact therewith until it moves beyond the ends of the latches, whereupon the latches spring into an abutting position against the flange, whereby the tang latches function to decelerate each of the movable members as well as to lock it into a deployed position. 18. The nozzle of claim 17 further including an annular, outwardly extending shoulder on the aft end portion of each of the nozzle segments to and including the penultimate segment; and an elastomeric ring seated in the surface of said shoulder so that it becomes confined between the shoulder and the inwardly extending flange of an adjacent nozzle segment when the segments are in deployed position, whereby the elastomeric ring functions as a hot gas seal and shock absorber between the nozzle segments. 19. The nozzle of claim 4 wherein there are three nozzle segments.