Abstract: An elongated armature can be moved rectilinearly but is preferably rotated between a first position in which it bridges the gap between two parallel rails to short circuit a very large DC current applied to one end of the rails and a second position where electrical contact with one rail is interrupted. Interruption of the circuit through the armature generates a massive arc which is driven by electromagnetic forces toward the second ends of the rails. Means are also provided for rapidly increasing the voltage across switch terminals to either more rapidly commutate the current into a secondary circuit and/or to more rapidly cause arc extinction. The switch is particularly useful for projectile launcher systems where the armature can be continuously rotated for burst firing. Preferably, the launcher rails are longitudinal extensions of the switch rails so that the arc initially produced by switch opening or armature rotation can be used directly in arc driving of projectiles.

Abstract: An electromagnetic projectile launching system is provided with a rail configuration in the breech area which increases the electromagnetic field to increase armature acceleration and initiate sliding current transfer at a lower current. Two configurations are disclosed. The first comprises multiple rails disposed parallel to the launcher barrel rails in tne breech region and connected in series such that current in the multiple rails flows in the same direction as current in the closest barrel rail. Connecting shunts are disposed in equal numbers on opposite sides of the barrel rails to balance electromagnetic forces. The second configuration comprises nonparallel barrel rails containing a bend in the breech region.

Abstract: Electromagnetic projectile accelerator comprising stationary coreless coils arranged in a row thus forming a tube. On the interior wall surface of said tube electrically opposite poled plates are mounted establishing an electric field.The magnetic projectile moving through the said electric field generates an alternating switching mode in the respective electromagnetic coils whereby the acceleration of the projectile within the tube is performed.

Abstract: The conductivity of the laminations in an armature which conducts current between the launcher rails or switch rails of an electromagnetic propulsion system is graded such that uniform current density is achieved in each lamination. The conductivity of each lamination, which increases from the breech end to the muzzle end of the armature, is related to that of the lamination at the breech end by a single proportionality factor which is a function of the length of the armature in the direction of armature travel, the half-width of the gap between the rails, the velocity of the armature, the magnetic permeability of the rails, and the conductivity of the breech laminations and of the rails.

Abstract: An electromagnetic projectile launching system is provided with an automatic plasma armature formation device. An arc created when a conductive armature breaks contact with a pair of conductive rails is commutated through an aperture in one of the rails to a second pair of conductive rails where the arc is used as a plasma driving armature to propel a projectile.

Abstract: An axi-symmetrical projectile, having a mass ranging from fractions of a gram to kilograms, is accelerated to velocities in the range of 10.sup.5 to 10.sup.7 centimeters per second by a propelling force produced by a plasma resulting from electric discharge. The discharge is imploded against the projectile surface so lines of the magnetic fields are approximately azimuthal around the projectile axis. The projectile is tapered so it experiences a net, stable axial accelerating force along the accelerator axis by the combined action of the magnetic field producing radially directed momentum and pressure on the plasma, the interaction of the magnetic field and ions induced by the plasma on the surface, as well as material the plasma ablates from the surface. The plasma discharge is initiated either in low density background gas between anode and cathode of a discharge module, or along an insulator surface between the electrodes in low density background gas.

Abstract: An electromagnetic projectile launcher having a pair of conductive rails with a breech and a nozzle end and an impedance electrically connected across the conductive rails adjacent the muzzle end of the conductive rails, and a second impedance which increases as the distance to the muzzle decreases, is disposed in the muzzle end of the rails and in arcs confined within the muzzle to commutate the current to the first impedance to substantially suppress any external arc as the projectile exits from the launcher.

Abstract: A switching system for commutating high DC current from a first to a second pair of conductors comprising a switching armature slidably engaging the first pair of conductors, insulating inserts disposed on the first pair of conductors adjacent the second pair of conductors and means for drawing two series arcs between the armature and the first pair of conductors as the current is commutated to the second pair of conductors.

Abstract: Resistive inserts are disposed in the breech of a projectile launcher to prevent excessive premature heating, to prevent premature movement of the projectile armature, and to prevent welding of the armature to the projectile rails during the period while the current builds up to the launching magnitude.

Abstract: Series resistance is added to the projectile current loop to assure there will be no premature launching or excessive heating of the projectile armature during the energizing cycle.

Abstract: A self-augmented parallel rail electromagnetic projectile launcher with a commutating circuit breaker disposed adjacent the breech.

Abstract: A multiple stage magnetic railgun accelerator (10) for accelerating a projectile (15) by movement of a plasma arc (13) along the rails (11,12). The railgun (10) is divided into a plurality of successive rail stages (10a-n) which are sequentially energized by separate energy sources (14a-n) as the projectile (15) moves through the bore (17) of the railgun (10). Propagation of energy from an energized rail stage back towards the breech end (29) of the railgun (10) can be prevented by connection of the energy sources (14a-n) to the rails (11,12) through isolation diodes (34a-n). Propagation of energy from an energized rail stage back towards the breech end of the railgun can also be prevented by dividing the rails (11,12) into electrically isolated rail sections (11a-n, 12a-n). In such case means (55a-n) are used to extinguish the arc at the end of each energized stage and a fuse (31) or laser device (61) is used to initiate a new plasma arc in the next energized rail stage.

Abstract: An electromagnetic propulsion power supply system utilizing mutual induction coils as transformers to provide high currents to the projectile rail conductors.

Abstract: A multistage electromagnetic accelerator in which energy is serially induced in stages of parallel rail having serially segmented segments or stages utilizing a high DC current source, circuit breakers, and induction coils with both primary and secondary windings to produce ultra high exit velocity in an armature and projectile which are slidably disposed between the parallel rails.