Reflector and coolant sealing structure for gas cooled nuclear reactor

Claim 1

IN A NUCLEAR REACTOR HAVING A CORE SUPPORTED ADJACENT THE LOWER END OF A VESSEL AND AN INNER WALL EXTENDING GENERALLY ABOVE THE CORE TO FORM A PLENUM CHAMBER THEREABOVE, A REFLECTOR AND COOLANT SEALING STRUCTURE COMPRISING A SERIES OF ELONGATED VERTICALLY DISPOSED BLOCKS FORMED OF A NEUTRON-REFLECTING MATERIAL ARRANGED IN SIDE-SIDE SPACED-APART RELATION AROUND THE PERIPHERY OF THE CORE AND EACH OF SAID BLOCKS BEING PIVOTABLY SUPPORTED AT ITS LOWER END FOR MOVEMENT IN A DIRECTION TOWARD AND AWAY FROM SAID CORE, SAID BLOCKS HAVING A LONGITUDINALLY EXTENDING GROOVE AND AN UPPER AND A LOWER TRANSVERSELY EXTENDING GROOVE IN EACH OF OPPOSING SIDE WALLS, WHEREBY SAID ADJACENT BLOCKS COOPERATE TO DEFINE LONGITUDINALLY EXTENDING SLOT AND TRANSVERSELY EXTENDING CHANNELS, A FIRST SEALING ELEMENT DISPOSED IN EACH OF SAID LONGITUDINALLY EXTENDING SLOT THEREBY LIMITING FLOW OF COOLANT GAS RADIALLY BY SAID BLOCKS, A SECOND SEALING ELEMENT DISPOSED WITHIN EACH OF SAID UPPER AND LOWER TRANSVERSELY EXTENDING CHANNELS THEREBY LIMITING VERTICAL FLOW OF COOLANT INTERMEDIATE SAID BLOCK, A SEGMENTED EXPANDABLE RING SUPPORTED BY SAID INNER WALL, AND SPRING MEANS FOR BIASING SAID RING INTO ENGAGEMENT WITH THE UPPER END OF SAID BLOCKS.