CATHODE UNIT Russian patent published in 1999 - IPC

FIELD: heavy-current vacuum electric-arc gears. SUBSTANCE: cathode unit has main frame that houses hollow thermal emission cathode whose cavity communicates with external source of plasma-forming substance and additional cathode located inside main frame and insulated from it electrically. Thermal emission cathode is fabricated in the form of package of plates with uniaxial holes mounted with clearance one with regard to another with the use of spacing plates placed between them and having uniaxial holes of bigger diameter. These plates form cavities from which surfaces electrons are emitted. EFFECT: reduced consumption of working substance through cathode, prolonged operational life of cathode due to reduced carry- over of cathode material from hollow during its evaporation, enhanced reliability of initiation of discharge in hollow. 5 cl, 2 dwg