Vacuum joint

Claim 1

A VACUUM JOINT STRUCTURE COMPRISING TWO JOINT MEMBERS PROVIDING AN INTERNAL EVACUATION SPACE, EACH OF SAID JOINT MEMBERS HAVING AN END SURFACE, MEANS FOR FORCING SAID END SURFACES TOWARD EACH OTHER, EACH OF SAID END SURFACES HAVING AN ANNULAR GROOVE THEREIN POSITIONED RADIALLY OUTWARD OF SAID INTERNAL SPACE, EACH OF SAID GROOVES HAVING ITS BOTTOM WALL DISPOSED SUBSTANTIALLY PARALLEL TO THE END SURFACE AND ITS SIDE WALL SURFACES INCLINED TOWARD EACH OTHER IN A DIRECTION MAKING THEM CLOSEST TOGETHER AT THE BOTTOM OF THE GROOVE, AN ANNULAR SEALING GASKET HAVING A RECTANGULAR CROSS SECTION AND RECEIVABLE IN SAID ANNULAR GROOVES WITH THE FOUR EDGES OF THE RECTANGLE IN CONTACT WITH SAID INCLINED WALL SURFACES, SAID ANNULAR GROOVES BEING SUFFICIENTLY DEEP THAT WHEN SAID JOINT MEMBERS ARE FORCED TOGETHER BY SAID FORCING MEANS SAID SEALING GASKET DOES NOT ENGAGE THE BOTTOM OF EITHER OF SAID GROOVES, SAID SEALING GASKET BEING SUBSTANTIALLY SOLID ACROSS ITS FACE SURFACES WHEREBY THE FORCE EXERTED AGAINST THE RADIALLY OUTER EDGES OF THE GASKET IS TRANSMITTED ACROSS THE GASKET AND RESISTED BY THE FORCE EXERTED AGAINST THE RADIALLY INNER EDGES OF THE GASKET, AND SAID JOINT STRUCTURE HAVING A PASSAGEWAY CONNECTING THE BOTTOM OF EACH OF SAID ANNULAR GROOVES WITH SAID INTERNAL SPACE IN SUBSTANTIALLY THE SAME PLANE AS SAID SEALING GASKET.