Automatic control system

摘要

An automatic control system is provided for regulating the emission of an X-ray tube of the type which is activated by the heating of a cathode filament by passing current through the filament, and which emits X-ray radiation systematically in accordance with the amount of tube current flowing between the anode and cathode of the tube, with a relatively high voltage being applied between the anode and cathode. Current is passed through the filament and a tube current sensor is coupled to the X-ray tube for developing a tube current signal representative of the magnitude of the current flowing between the cathode and anode of the X-ray tube. Coupled to the current sensing circuit and responsive to the tube current signal is a circuit for generating a filament current control signal. A filament current control circuit is coupled between the filament current control signal generating means and the filament and is responsive to the filament current control signal for regulating the amount of current flowing through the filament, whereby the filament current is automatically adjusted in accordance with the magnitude of the tube current to maintain the tube current at a predetermined level.