Supporting structure

Claim 1

IN A THERMIONIC ELECTRON DISCHARGE DEVICE, INTEGRAL MEANS FOR SUPPORTING A CATHODE WITHIN A MINIATURE CYLINDRICAL GRID ELECTRODE HAVING A GIVEN INTERNAL DIAMETER COMPRISING: A SUBSTANTIALLY DISC-LIKE SUPPORT INSULATOR FORMED OF FIRST AND SECOND OPPOSITELY DISPOSED SURFACES HAVING SAID INSULATOR THICKNESS CONSTITUTING THE VERTICAL DISTANCE THEREBETWEEN, SAID INSULATOR HAVING AN INTERNAL WALL DEFINING AN AXIAL APERTURE THERETHROUGH, SAID FIRST SURFACE HAVING AT LEAST A RAISED FIRST CIRCULAR LEVEL PROXIMAL TO SAID APERTURE AND A LOWER CIRCULAR SECOND LEVEL DISTAL THERETO WITH A PORTION OF SAID INSULATOR THICKNESS DEFINING A SUBSTANTIALLY VERTICAL INSULATIVE AREA THEREBETWEEN TO EFFECT AT LEAST A PARTIAL SHADOWING OF SAID SECOND LEVEL BY SAID FIRST LEVEL TO INHIBIT SUBLIMATION LEAKAGE THEREACROSS, SAID FIRST LEVEL HAVING A CIRCULAR AREA ADJACENT SAID APERTURE AND SAID SECOND LEVEL BEING SUBSTANTIALLY PLANAR AND HAVING A CIRCULAR AREA ADJACENT THE PERIPHERY THEREOF SAID SUPPORT INSULATOR BEING OF A DIAMETER SMALLER THAN THE INTERNAL DIAMETER OF SAID ELECTRODE; A SUBSTANTIALLY CYLINDRICAL EYELET ENCOMPASSING SAID CATHODE AND CONNECTED THEREWITH, SAID EYELET BEING DISPOSED WITHIN SAID AXIAL APERTURE AND SPACED FROM SAID INTERNAL WALL THEREOF, SAID EYELET HAVING A TERMINALLY FORMED OUTSTANDING SEATING LEDGE AFFIXED TO ONLY SAID FIRST SURFACE OF SAID SUPPORT INSULATOR ON SAID FIRST LEVEL THEREOF ON THE AREA PROXIMAL TO SAID APERTURE TO EFFECT SPACED ALIGNMENT OF SAID EYELET WITHIN SAID APERTURE; AND AN INSULATOR RETAINER EXTERNALLY DIMENSIONED TO SLIDE WITHIN SAID ELECTRODE FOR AFFIXATION THERETO, SAID RETAINER HAVING AN INTERNAL DIMENSION AT LEAST EQUAL TO THE DIAMETER OF SAID INSULATOR TO PERMIT INSULATOR PLACEMENT THEREIN, SAID RETAINER BEING TERMINALLY FORMED WITH AN INSTANDING SEATING LEDGE SECURED TO SAID SUPPORT INSULATOR ON THE PHERIPHERAL METALLIZED AREA ON ONLY THE LOWER SECOND LEVEL OF SAID FIRST SURFACE.