초록 ▼

A rocket propelled vehicle includes a lower stage solid propellant rocket motor and at least one upper stage solid propellant rocket motor. Each of the rocket motors includes a case, a nozzle and a solid propellant having a central combustion chamber, with the case of the lower stage motor, in a pre

A rocket propelled vehicle includes a lower stage solid propellant rocket motor and at least one upper stage solid propellant rocket motor. Each of the rocket motors includes a case, a nozzle and a solid propellant having a central combustion chamber, with the case of the lower stage motor, in a preferred embodiment, being open at the forward end and the case of the upper stage motor being open at the aft end and forming a continuation of the open end of the lower stage case, with a layer of slow burning material cast on the surface defining the central combustion chamber of the upper stage solid propellant, and with ignition of all stages being accomplished approximately simultaneously through operation of a single ignition system. Pressurization of the lower and upper stages during burning of the lower stage propellant counteracts and substantially eliminates compressive stresses in the upper stage vessel membranes, which compressive stresses are induced by transmission of lower stage thrust to the upper stages and the payload beyond by superimposing tensile stresses therein, and additionally provides a source for the secondary discharge of gases. Such gaseous discharge may be used to create a boundary layer surrounding the skin of the vehicle for diminishing friction with the medium through which the vehicle flies, and may also be used for thrust vector control to steer the vehicle.

대표청구항 ▼

A multi-stage rocket comprising, a lower stage rocket motor including a first nozzle and having a first solid propellant and a first case, said first solid propellant having a perforation therein forming a first central combustion chamber, said first case having a forward end and an aft end with sai

A multi-stage rocket comprising, a lower stage rocket motor including a first nozzle and having a first solid propellant and a first case, said first solid propellant having a perforation therein forming a first central combustion chamber, said first case having a forward end and an aft end with said nozzle being attached to said aft end of said first case, at least a first upper stage rocket motor including a second nozzle and having a second solid propellant and a second case, said second solid propellant having a forward end and an aft end with said second case being open at the aft end of said second solid propellant and attached to said second nozzle, said second solid propellant having a perforation therein forming a second central combustion chamber with a first layer of slow burning material covering the surface defining said second central combustion chamber, and ignition means provided in operative association with said first and second combustion chambers and operative when activated, to ignite said propellants in said lower and upper stages approximately simultaneously, the burn rate and thickness of said slow burning material covering the surface defining said second central combustion chamber being arranged so that, upon operation of said ignition means, burning of said slow burning material lasts through substantially the entire burn of said first solid propellant and delays for a corresponding period exposure of the surface defining said second central combustion chamber and thereby burning of said second solid propellant, whereby said upper stage at least is pressurized during burning of said first solid propellant, such pressurization reducing compressive stresses in said second case induced by transmission of lower stage thrust to forward portions of the rocket by superimposing counteracting tensile stresses therein, and additionally providing a source for the secondary discharge of gas during burning of said first solid propellant.