Patent Number: 046631089
Section: claims

1. A vacuum liner for containing plasma in a high energy plasma device, said liner comprising: a vacuum tight liner wall made up 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 a plasma path, said sections being bellows-shaped and having a plurality of corrugations extending transversely to the axis of said plasma path; and  means for limiting the plasma for said liner wall and comprising a ring formed by beads nested in the interior groove formed by each of said corrugations, said beads extending from their grooves inwardly past the interior ridges flanking them, the material from which said beads are formed having a higher melting temperature than that of the material from which said sections are formed. 2. A vacuum liner as set forth in claim 1 wherein said liner wall defines a torus. 3. A vacuum liner as set forth in claim 1 wherein each bead has an aperture therethrough and each ring further comprises fastening means extending through the apertures of the beads forming said ring. 4. A vacuum liner as set forth in claim 1 wherein said liner wall is formed of steel. 5. A vacuum liner as set forth in claim 1 wherein said beads are formed of carbon. 6. A vacuum liner as set forth in claim 1 wherein certain of said beads have a stem received by a groove and an arm extending outwardly over an interior ridge partially defining said groove. 7. A vacuum liner as set forth in claim 6 wherein said arm overlaps a bead disposed in an adjacent groove. 8. A vacuum liner as set forth in claim 6 wherein said certain beads having oppositely extending arms, each arm overlapping a bead in a respective adjacent groove. 9. A vacuum liner as set forth in claim 8 wherein said bead in an adjacent row is formed as a split cylinder having a flat surface facing the plasma. 10. A vacuum liner as set forth in claim 3 wherein said fastening means is a piece of resilient wire having a length greater than the circumference of its ring so that the ends of said piece both are disposed in the apertures of adjacent beads. 11. A vacuum liner as set forth in claim 10 wherein all beads in a ring are held in compression and wherein each bead has a tail portion with a concavity and further has a nose portion sized for reception in the concavity of the next bead, whereby all portions of said wire are shaded from said plasma. 12. A vacuum liner as set forth in claim 1 wherein said bellows-shaped sections are first sections and wherein said liner wall also includes second sections each having a peripheral wall defining an interior with open ends, the interiors of said second sections also forming parts of said plasma path, said second sections having generally smooth inner surfaces. 13. A vacuum liner as set forth in claim 12 wherein said means for limiting movement of the plasma further comprises a ring formed by tiles substantially covering the inner surface of each second section.