Abstract: Direct current ballasting and starting circuitry for efficiently operating a gaseous discharge lamp on direct current. A series-pass switching transistor in one of a pair of input lines alternately switches between on and off states to periodically supply pulses of energy from a source of direct current voltage. During steady-state operation, current sensing circuitry limits the maximum current conductable by the transistor such that the output of the circuitry is current regulated. A filter, in series with the transistor, smoothes the pulses of energy delivered by the transistor into direct current with a comparatively small alternating current component. Starting circuitry in series connection between the filter and an output terminal, senses the nonionized state of the lamp and provides a voltage pulse of sufficient magnitude and duration to initiate ionization in the lamp, but permits uninterfered passage of current through the filter to the output.

Abstract: A closed loop system is disclosed for monitoring and regulating the power applied to the stator of an induction motor for controlling the operation of the rotating anode of an X-ray tube in order to insure acceleration of the rotor to a selected speed of rotation, to maintain the selected speed of rotation, and to provide a braking voltage to the rotor as desired. The system provides direct inter-related operation of an anode rotor, an anode rotor rotation sensing detector, and an X-ray generator.

Abstract: Apparatus to indicate the temperature of an X-ray tube target includes an analog storage circuit to simulate the heat energy stored. Input signals representing the current and the voltage of the electron beam in the tube are multiplied to give a signal representing the instantaneous power input. The power signal is integrated in the storage circuit to give a temperature signal representing the total heat input. The temperature signal is dissipated by a cooling curve circuit representing the heat loss with time. An indicator reads the temperature signal.Input voltage and current signals are processed to refer them to ground before multiplication. The current signal is corrected to set its zero value. The voltage signal derived from a transformer primary is corrected for transformer regulation. To eliminate spurious inputs the power signal is gated to the storage circuit only when a measured current is flowing.

Abstract: Failure inducive operating conditions of an X-ray generator tube are sensed. Some of the sensed operating conditions are events such as hot overload of the target and thermal shock of the target, while other sensed operating conditions include hot target bearing use and thermionic cathode filament heater use. Certain of the sensed operating conditions are integrated, with the integrated output being compared against a predetermined standard to yield a prediction of remaining operating life. Other sensed conditions, if present, are indicative of incipient failure without integration. The integrated signals are stored in electrochemical cells and read out periodically for a prediction of incipient tube failure.

Abstract: An apparatus for sensing the speed of a rotating anode of an X-ray tube and for providing signals responsive to the detected rotating speed.