Abstract: A dual concentric poppet valve assembly (44) includes an assembled body (45) having an opening (55) therethrough and having a sealing surface (56) surrounding the opening. A first member (46) is mounted in the body opening for axial movement relative to the body. The first member has a first sealing surface (70) arranged to be moved toward and away from the body sealing surface (56) to define a first variable-area orifice (96) therebetween. The first member has a concentric opening (72) therethrough and has a second sealing surface (71) surrounding the first member opening. A second member (48) is mounted in the first member opening for co-axial movement relative to the first member. The second member has a sealing surface (83) arranged to be moved toward and away from the first member second sealing surface (71) to define a second variable-area orifice (98) therebetween.

Abstract: A device (20) for providing a uniformly-variable orifice includes an object (21) having an outer surface, a wall (24) surrounding the object in spaced relation to the outer surface and defining an annular orifice therebetween; and deforming means (F.sub.1) for causing at least one of the surface and wall to move perpendicularly and uniformly toward the other of the surface and wall without substantially altering the geometric shape of the annular orifice, whereby the movable member may be moved relative to the other to vary the area of the orifice. In the preferred embodiment, the area of the orifice varies substantially linearly with application of the deforming displacement.

Abstract: The present invention provides an improved hot gas control valve (20) which is adapted to apportion a gas flow, such as that issuing from a solid propellent gas generator, among a plurality of outlets communicating with rocket thruster nozzles (36). The improved valve has a body (21) and a valve member (22). The body has an inlet (24) communicating with an internal cavity. The cavity is partially bounded by a partially-spherical concave surface (32). The body has a plurality of outlet passages terminating in ports at the concave body surface. The valve member is operatively arranged within the cavity for omni-directional pivotal movement therewithin. The valve member has a surface (40) sealingly engaging the body concave surface and terminating in an edge (41). This valve member edge cooperates with the body ports to form variable-area metering orifices (A, B, C and D) therebetween.

Abstract: A control valve assembly for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve is switched by a pressure signal depending on the state of its counterpart's piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow.

Abstract: An adjustable converging-diverging nozzle (10) includes a body (11) having a flow passageway (14) therethrough. The passageway is configured to define an entrance section (18), a narrowed throat section (19), and an exit section (20). Two opposing vane members (12,13) are pivotally mounted on the body. Each vane member has a first surface (33,33') facing into the passageway to form a movable wall portion of the throat section. Each first surface is eccentric to the pivotal axis (38,38') of the associated vane member. A pair of actuators (42,43) are mounted on the body for selectively varying the angular positions of the associated vane members. The vane members may be moved to a closed position to reduce the orifice area of the throat section to zero, or may be moved to other angular positions to vary the magnitude and/or direction of the thrust vector of hot gas discharged through the nozzle. The invention also provides an improved method of operating the nozzle by selectively moving the vane member(s).

Abstract: A two-axis force motor (10) has an armature (12) mounted within a body (11) for omni-directional pivotal movement relative to the body. The motor has an electrical section for causing the armature to pivot selectively in either or both of two mutually-perpendicular intersecting planes (x-x,y-y). The motor also has a fluidic section, which includes a plurality of valve members (64) spaced about the armature. These valve members are biased to engage the armature and are closed when the armature is in a null position. When the armature is pivoted off-null, some of the valve members will be opened, while others will remain closed.