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 of variable throat section for an aerospace vehicle thruster, the nozzle including a cylindrical housing presenting a throat of aperture diameter less than the diameter of the housing, and a needle suitable for sliding inside the housing between a high discharge rate front position in which the nose is set back from the throat of the housing, and a low discharge rate rear position in which the nose is in abutment against the throat, the needle including a rod for sliding inside the housing of the nozzle, the rod terminating in a nose of decreasing diameter. The nose of the rod is suitable for coming into abutment against the throat of the nozzle housing forming a seat and includes at least two axial grooves formed in its outer periphery to allow gas to pass when the nose is axially in abutment against the throat of the housing of the nozzle.

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 of variable throat section for an aerospace vehicle thruster, the nozzle including a cylindrical housing presenting a throat of aperture diameter less than the diameter of the housing, and a needle suitable for sliding inside the housing between a high discharge rate front position in which the nose is set back from the throat of the housing, and a low discharge rate rear position in which the nose is in abutment against the throat, the needle including a rod for sliding inside the housing of the nozzle, the rod terminating in a nose of decreasing diameter. The nose of the rod is suitable for coming into abutment against the throat of the nozzle housing forming a seat and includes at least two axial grooves formed in its outer periphery to allow gas to pass when the nose is axially in abutment against the throat of the housing of the nozzle.