Patent Number: 046541829
Section: claims

1. Apparatus for containing plasma in a high energy plasma device, said apparatus comprising: a confinement vessel having a wall defining a closed interior including a plasma path, said wall having an inside surface;  a magnet system including first conductors disposed outside said vessel for generating a magnetic field extending inside said closed interior;  an armature ring disposed inside said wall;  means for supporting said ring for rotation in a plane extending transversely of said plasma path and for preventing substantial movement of said ring in the direction of said plasma path, said ring including armature conductors extending at an angle to lines of force of said magnetic field;  means for supplying direct current to said armature conductors;  a protective coating carried by said ring and facing said plasma path to provide a first wall whereby the interaction of said magnetic field and the current in said armature conductors causes rotation of said armature ring to prevent damage to said wall due to localized heating.  a vacuum tight liner wall made up, at least in part, by a series of sections, each section having a closed peripheral wall defining an interior with open ends, with adjacent interiors of adjacent sections forming, at least in part, a plasma path, at least one of said sections having an inside surface and an outside surface with its interior being generally circular in section;  a magnet system including first conductors disposed outside said one section for generating a magnetic field extending inside said one section;  an armature ring supported inside said one section, said ring carrying means for entering into rolling engagement with the inside surface of said one section, said ring comprising current carrying armature conductors extending at an angle to lines of force of said magnetic field; and  armor tiles carried by said ring and facing said plasma path for acting as plasma limiters whereby the interaction of said magnetic field and the current in the armature conductors causes rotation of said armature ring in said one section to prevent damage to said liner wall due to localized heating.  rotatably mounting inside said section an armature ring comprising rollers for engaging said inside surface and further comprising armature conductors extending at an angle to lines of force of said magnetic field;  affixing armor tiles to said ring facing said plasma path for acting as plasma limiters;  causing direct current to flow through said armature conductors whereby the interaction of said magnetic field and the current in said armature conductors results in rotation of said armature ring to prevent damage to said section due to localized heating. 2. Apparatus as set forth in claim 1 further comprising a plurality of said armature rings disposed at spaced locations along said plasma path. 3. Apparatus for containing plasma in a high energy plasma device, said apparatus comprising: 4. Apparatus as set forth in claim 3 wherein said liner wall defines a torus. 5. Apparatus as set forth in claim 3 further comprising means for supplying direct current to said armature conductors of said armature ring. 6. Apparatus as set forth in claim 5 wherein said armature ring is electrically conductive and comprises a first annular end and a second annular end with said armature conductors comprising spaced bars interconnecting said first and second ends. 7. Apparatus as set forth in claim 6 wherein said means for supplying direct current comprises a first brush mounted on a first conductive standard extending through said liner and slidably engaging said one annular end, and a second brush mounted on a second conductive standard extending through said liner and slidably engaging said second annular end, said brushes functioning to direct current through said bars and to hold said armature ring from substantial axial movement. 8. Apparatus as set forth in claim 6 wherein said means for entering into rolling engagement comprises rollers extending between said first and second annular ends between adjacent bars. 9. Apparatus as set forth in claim 8 wherein each of said annular ends has a plurality of cavities, one cavity in each of said annular ends forming an aligned pair, each roller having a pair of oppositely extending lugs received in a respective pair of cavities to retain the roller. 10. Apparatus as set forth in claim 9 wherein each cavity holds spring means bearing against one of said lugs for biasing its corresponding roller against the interior surface of said one section. 11. Apparatus as set forth in claim 3 wherein said armature ring is formed of material having a greater coefficient of thermal expansion than the coefficient of expansion of the material of said one section so that upon heating, said armature ring expands into engagement with the interior surface of said one section. 12. A method of protecting a vacuum tight liner wall in a high energy plasma device, said liner wall including a section having a closed peripheral wall defining an interior with open ends and forming, in part, a plasma path, said section having an inside surface and an outside surface with said interior being generally circular in section, said plasma device including a magnet system including first conductors disposed outside said section for generating a magnetic field extending inside said section, said method comprising the following steps: