Abstract: An artillery piece which has a gun barrel made up of a parallel rail electromagnetic launcher bore. Current from a source is injected into the rails to propel a bridging armature and projectile. The velocity of the porjectile is measured as it traverses a certain position within the barrel and the measured velocity is compared with a predetermined desired velocity. The velocity of the projectile is modified (if required) toward the muzzle end of the rails as a result of the comparison.

Abstract: An electromagnetic launcher having spaced-apart rails for launching a projectile by means of a current-carrying armature between the rails includes a breech end loop connected to a current commutating firing switch. A low resistance shorted loop is positioned in proximity to the breech loop and generates a current in a direction counter to the commutated breech current. The arrangement reduces the equivalent breech inductance which in turn reduces communication arcing energy as well as the duration of arcing, thereby prolonging firing switch life.

Abstract: An electromagnetic projectile launcher with augmenting conductors and a circuit breaker at the breech which closes as the projectile is launched to recover inductive energy from the launching rails for successive shots and a launcher with coaxial conductors which greatly reduce external flux.

Abstract: An electromagnetic projectile launching system is provided with a pair of conductive projectile launching rails which are connected to a high current inductive power source. Current from an inductive energy storage coil is switched to the launcher rails to successively launch a series of projectiles. As each projectile is launched, the inductance of the coil is reduced to increase inductor current so that each successive projectile is launched at approximately the same muzzle velcoity.

Abstract: Electrical circuit inductively coupled to the circuit of an electromagnetic projectile launcher for beneficially reducing switch arcing duration and switch arc energy dissipation.

Abstract: A multiple bore electromagnetic projectile launcher is provided with series circuit elements connected to the muzzle end of conductive rails of a bore to continue current conduction in those rails following the launch of a projectile and during the launch of a successive projectile. This current flow augments the flux in the successive bore during the launching of a successive projectile. Individual firing switches can be provided for each bore or additional conductive rails can be provided in an automatic switching arrangement to conduct current from a muzzle of a fired bore to the breech of a successive bore.

Abstract: An electromagnetic launcher having parallel rails bridged by a projectile driving armature. Another set of rails, acting as current feed rails, delivers current, from an energy source, to the projectile rails at the far or muzzle end thereof as opposed to the breech end, as is done in conventional electromagnetic launchers.

Abstract: Electrical circuitry for preventing or substantially reducing electrical arcing at the muzzle of an electromagnetic projectile launcher. The circuitry provides a plurality of switches which interconnect portions of the rails of the launcher so that a unidirectional current flows through, the armature of the launcher is a first direction when the armature is in a first section of the launcher and a second section of the launcher. The switches, also cause a current, in a direction opposite the direction of the first direction, to flow through the armature of the launcher when the armature is in the second section of the launcher.

Abstract: A switching system for switching large electric currents such as those utilized in the electromagnetic launching of projectiles, includes a plurality of controllable switching elements such as solid state switching devices which are electrically connected in parallel with each other and are also electrically connected in parallel with a pair of mechanical switch contacts. Current flow through the solid state switching devices also flows through a series connected structure which utilizes electromagnetic forces generated by this current to close the mechanical contacts, thereby shorting across the solid state switching device circuit branches. This switching system can be utilized in an electromagnetic projectile launching system to conduct current between a pulse current source and a pair of projectile launching rails. Launch current flow is initiated by the switching system and the mechanical switch contacts remain closed until current is interrupted at a current zero following a projectile launch.

Abstract: An electromagnetic launcher system for small diameter high velocity penetrator projectiles and larger diameter, slower projectiles is provided with a single high current pulse power supply. At least two bores of substantially different cross section are connected to the power supply. Augmentation conductors are utilized adjacent the larger diameter bore to achieve the desired acceleration of the large diameter projectile with a smaller root mean square current than used for the acceleration of the small diameter projectile to a desired high velocity.

Abstract: An electromagnetic launcher system which includes a homopolar generator pulse power supply recovers post-launch rail inductive energy and transfers it to the rotor of the homopolar generator to increase its kinetic energy for use in one or more subsequent launchings.

Abstract: An electromagnetic parallel rail launcher with an augmentation winding for post-firing inductive energy recovery. A power supply includes a storage inductor which, in conjunction with the inductance of the augmenting winding, provides the inductive energy storage prior to firing. As the launcher projectile exits, the storage inductor is substantially decoupled from the rail and augmenting winding inductance, so that a high efficiency inductive energy transfer may be accomplished between the rails and augmenting winding.

Abstract: An electromagnetic launcher having spaced-apart rails for launching a projectile includes a plurality of stages connected to the rails for supplying makeup current during a projectile launch. Each stage includes an inductive power supply and an electrically conducting loop physically adjacent the rails for a predetermined length and including a conducting switch, such as a controlled rectifier array. As a projectile launching armature enters the loop area, a countercurrent is built up in the loop and at current zero the switch reverts to a non-conducting condition, thereby causing injection of the inductive current into the rails.

Abstract: A container toothbrush for holding liquid toothpaste is provided and consists of a replaceable container having a threaded end portion, a toothbrush having a plurality of projecting bristles, a threaded counter bore that is removably attaches the toothbrush to the threaded end portion of the replaceable container, and a device for dispensing the liquid toothpaste from the container onto the bristles of the toothbrush just prior to brushing teeth.

Abstract: An electromagnetic projectile launching system is provided with a passive, conductive loop for energy retention, dissipation or recovery. In a parallel rail launcher, this passive loop is inductively coupled to substantially link magnetic flux produced within the launcher by current flowing in a pair of parallel projectile launching rails. During projectile acceleration, parasitic current flow in the passive inductive loop turn or turns is prevented by a rectifier array. When the projectile exits, post-firing rail inductive energy is inductively and rapidly transferred to the passive inductive loop and is either dissipated there or may be beneficially employed to help accelerate a successive projectile.

Abstract: The electromagnetic projectile launching systems of this invention accelerate projectiles by switching current from a current source to a pair of conductive projectile launching rails such that current flows through the rails and through an armature between the rails to produce an accelerating force on a projectile and the rate of current injection into the rails is controlled so that the initial projectile acceleration occurs at a reduced current level compared to the current used for subsequent projectile acceleration. This reduced current level is provided by initially shorting a resistor connected between one of the rails and the power source or alternatively by inserting a resistor in series with a switch which partially commutates current from the current source to the projectile launching rails. The maximum rail surface temperature during a launch is reduced by controlling the rate of initial current injection.

Abstract: An internally augmented, parallel rail electromagnetic projectile launching system includes a plurality of projectile launching rail pairs wherein the stacked height of the rails adjacent to the launcher bore decreases from the breech end to the muzzle end of the launcher. The launcher rail pairs may be electrically connected in series with each other and in series with an external current source. Alternatively, a separate though not necessarily entirely independent current source may be provided for each pair of rails and switching means may be included to substantially simultaneously connect each current source to its associated rail pair.

Abstract: An electromagnetic projectile launcher is provided with a pair of parallel conductive projectile launching rails which are generally T-shaped with a significant current carrying cross section located symmetrically around a horizontal bore center line. Augmenting conductors which may be either series or parallel connected are located adjacent to the projectile launching rails. In favorable embodiments, force augmentation is also achieved by a reduction in launcher rail height from the breech to the muzzle end.

Abstract: A current limiting apparatus is provided with a pair of generally parallel conductive rails each including an initial high conductivity portion and a more resistive portion. A sliding armature conductor is positioned between the rails and makes sliding electrical contact with the rails such that a high fault current flowing through the rails and through the armature conductor produces forces which propel the armature conductor along the rails thereby increasing the resistance through which the current flows. Final interruption of the current is accomplished by a separate circuit breaker which is connected in series with the current limiting apparatus.

Abstract: These electromagnetic guns or launchers comprise a pair of switching rails ith a slidable switching armature associated therewith for commutating a high direct current into a pair of projectile rails which are arranged in tandem with the switching rails and are electrically connected thereto. The kinetic energy of the switching armature is transferred to the projectile armature assembly so that the projectile armature assembly has an initial velocity as the current is commutated to the projectile rails. The projectile armature assembly may be mounted on and carried by the switching armature during its entire travel or the switching armature may bump the projectile armature assembly into the conductive breech region of the projectile rails at the end of its travel.