Tomographic x-ray apparatus for the production of transverse layer images

A tomographic x-ray apparatus for the production of transverse layer images of a radiography subject, comprising a patient support, an x-ray measuring arrangement including an x-ray source, which generates an x-ray beam penetrating the radiography subject, and a radiation receiver which determines the radiation intensity behind the subject, a drive device for the measuring arrangement, a rotating frame for effecting rotational scanning movement of the measuring arrangement, and a measured value converter for the transformation of the signals delivered by the radiation receiver into a layer image, a stationary apparatus part and the rotating frame having a plurality of slip ring arrangements therebetween for the supply of current to the x-ray tube, each slip ring arrangement comprising two coaxial ring members (16, 21), of which one (16) is connected with the rotationg frame (3), and the other is stationary, said coaxial ring members having sliding contacts (18, 19, 20) for the transmission of the x-ray tube current, said stationary part and rotating frame having interpenetrating axially projecting ribs (28 to 35), and having central openings (17, 22) of size to receive the patient support (1) therethrough, said plurality of slip ring arrangements having first and second slip rings (11, 13) in engagement with respective ones of the sliding contacts (18, 20) for conducting x-ray tube current during rotational scanning movement of the measuring arrangment, said interpenetrating axially projecting ribs defining first and second annular chambers (27, 36) containing the first and second slip rings (11, 13) respectively, and including oppositely axially projecting laterally overlapping annular ribs (29, 30, 33) of insulating material between said first and second annular chambers (27, 36) and defining a meandering air path between said first and second slip rings (11, 13), so as to electrically isolate said first and second slip rings with air without immersion thereof in insulating oil.