Abstract: In an exemplary embodiment, the rotary anode is mounted by magnetic bearings and is provided with an auxiliary device for conducting the anode current to the external power supply. The auxiliary device comprises at least one auxiliary cathode which rotates with the anode and an auxiliary anode which is arranged concentrically to the anode rotary axis on a stationary part. The heating of the auxiliary cathodes can proceed via generator windings which rotate with the rotary anode and associated stationary exciting windings arranged about the x-ray tube. It is also possible to provide for this purpose a rotating transformer whose primary windings externally annularly surrounds the x-ray tube and whose secondary winding is arranged on a rotating anode part.

Abstract: An exemplary embodiment comprises an image intensifier television chain, a device for dose output regulation during fluoroscopy, a function generator for determining the exposure voltage from the fluoroscopic voltage, and an automatic exposure control which keeps the integral of the light output from image intensifier per exposure constant. A manual selector is present by which the exposure voltage can be set, e.g. at any whole number value between 50 kV and 125 kV independently of the automatic circuit for setting this voltage. The automatic exposure control is designed in such manner that, given the manual setting of the exposure voltage, the function generator changes the x-ray tube current given constant exposure time for patient thicknesses that lie below a lower value and, for patient thicknesses above this lower value, changes the exposure time given constant x-ray tube current.

Abstract: The measuring arrangement contains a frequency converter which exhibits a light source which emits light pulses whose frequency corresponds to the x-ray tube current. A light conductor leads from the light source to an opto-electric transducer which is connected to an analog frequency meter and/or a pulse counter.

Abstract: In the illustrated embodiments a logical switching member is energized from a common power supply at the time that a manual switch is actuated for initiating an x-ray exposure. If the logical switching member does not receive an inhibiting signal within a definite inhibition interval less than a minimum exposure time, the switching member reaches a normal operating state and supplies its logical output signal to turn off the x-ray source. The inhibiting signal is not generated if the radiation detector fails to receive radiation from the x-ray source, or if there is a circuit failure in the inhibiting signal generating circuitry connected to the input of the switching member, or if the dosage fails to increase at least at a selected minimum rate during the inhibition time interval.