Abstract: A nozzle having a movable diverging section, the nozzle including a stationary throat forming a ball joint and a diverging section having a top portion that is movably mounted around the throat; an annular lubrication chamber being interposed between the stationary throat and the top portion of the diverging section, the annular lubrication chamber containing a grease seal; an annular throttling element arranged between the stationary throat and the diverging section downstream from the annular lubrication chamber, the annular throttling element being made of refractory material; and an annular thermal protection element arranged between the stationary throat and the diverging section downstream from the annular lubrication chamber and upstream from the annular throttling element, the annular thermal protection element closing the lubrication chamber in its bottom portion.

Abstract: A modulator device for modulating a gas ejection section, includes a shutter member for partially shutting a nozzle throat, a control guide of the shutter member, a main piston, and a primer piston. The control guide is movable between a retraction position for retracting the partial shutter element relative to the nozzle throat and a shutting position in which the partial shutter element is in contact with the nozzle throat. The primer piston is movable between a rest position and a priming position for priming the main piston when the pressure in the modulator device reaches a first predetermined value. The main piston is movable between a first position for locking the control guide against movement in its retraction position, and a second position for locking the control guide when the pressure in the modulator device reaches a second predetermined value less than the first predetermined value.

Abstract: A modulator device for modulating a gas ejection section, includes a shutter member for partially shutting a nozzle throat, a control guide of the shutter member, a main piston, and a primer piston. The control guide is movable between a retraction position for retracting the partial shutter element relative to the nozzle throat and a shutting position in which the partial shutter element is in contact with the nozzle throat. The primer piston is movable between a rest position and a priming position for priming the main piston when the pressure in the modulator device reaches a first predetermined value. The main piston is movable between a first position for locking the control guide against movement in its retraction position, and a second position for locking the control guide when the pressure in the modulator device reaches a second predetermined value less than the first predetermined value.

Abstract: A nozzle having a movable diverging section, the nozzle including a stationary throat forming a ball joint and a diverging section having a top portion that is movably mounted around the throat; an annular lubrication chamber being interposed between the stationary throat and the top portion of the diverging section, the annular lubrication chamber containing a grease seal; an annular throttling element arranged between the stationary throat and the diverging section downstream from the annular lubrication chamber, the annular throttling element being made of refractory material; and an annular thermal protection element arranged between the stationary throat and the diverging section downstream from the annular lubrication chamber and upstream from the annular throttling element, the annular thermal protection element closing the lubrication chamber in its bottom portion.