METHOD FOR DETECTION OF DISTANCE BETWEEN ELECTRODES OF VACUUMISED ELECTRIC VACUUM INSTRUMENT (VERSIONS) Russian patent published in 2010 - IPC H01J9/42 

FIELD: electricity.

SUBSTANCE: invention relates to methods for detection of distance between electrodes of electric vacuum instruments (EVI). Volt-ampere curve (VAC) of current l_0sk is run with grid under negative potential from voltage of Usk between cathode and grid of EVI with filament current l_no=0, corresponding to specified initial temperature, at which electronic injector of EVI is assembled, and current VAC l_1sk - from grid at specified value of filament current l_nz>0, corresponding to established increased temperature, dependances of these currents logarithms lgI_0sk and lgI_1sk are built on curve on value of 1/U_sk, on linear sections of these dependences corresponding to mode of autoelectronic emission current mode from grid, two points are chosen, which satisfy the requirement of lgI_0sk = lgI_1sk, according values 1/U_0sk and 1/U_1sk are found, and values of voltages U_0sk and U_1sk are calculated, then value of distance d_1sk is calculated between grid and cathode at specified value of filament current lnz using the following formula: d_1sk=d_0sk(U_1sk/U_0sk), where d_0sk - specified distance between grid and cathode produced in process of electronic injector assembly at specified initial temperature. In the second version similarly distance is identified between grid and anode of EVI, where anode is source of autoelectronic emission current.

EFFECT: invention provides the possibility to detect least distance between EVI electrodes with high accuracy as temperature of its elements changes.

2 cl, 4 dwg