MANUFACTURE OF HELICAL COIL CONTAINER

PURPOSE:To form easily a helical coil container with high accuracy by forming a fitting structure and key structure worked with desired accuracy in a connection of the coil container divided into a plurality of parts in the winding direction. CONSTITUTION:In a connection part of a helical coil container 14 divided into a plurality of parts in the winding direction, there are provided a fitting 12 structure and a key 11 structure formed with desired accuracy in a helical groove of a discharge tube. After the key 11 is inserted and connected by bolts 13, the connection is formed by being covered with a sealing film 15 from the inside of the container 14. Thus, the container 14 spaced from the discharge tube can be easily obtained with high accuracy. Also, a coil is wound around the container groove and a lid 16 of the container 14 is mounted with bolts 17 having a seal cap 18. Then, when the contact surfaces of the container 14 and lid 16 are seal welded 19 in the winding direction, stable plasma enclosure is provided and a helical coil holding air-tightness is obtained. Further, when another seal structure 20 is provided outside the container 14, only repair spots can be repaired from the outside after assembling of the coil without disassembly.