CATHODE STRUCTURE FOR ELECTRON TUBE OPERATING IN MAGNETIC FIELD AND ITS MANUFACTURE

摘要

PURPOSE:To prevent the falling off of an insulator, with which heater wire is coated, due to the vibration of a heater by arranging between a cathode sleeve and the heater a layer formed of soft material to absorb the vibration of the heater. CONSTITUTION:There are a cathode sleeve 11 to which electron emission material 12 is applied and heaters 14 which are mounted in a sleeve-shaped alumina fabric 21 inside thereof. The heater 14 which has the surface coated with an alumina insulated film by electrodeposition after a heater wire is bent in multiple layers is mounted in the soft sleeve-shaped alumina fabric 21 to absorb the vibration of the heater. In this way, the falling off of an insulator is prevented and the mutual dielectric breakdown and electric short of the heaters are prevented.