Abstract: The invention relates to a rotary-anode X-ray tube comprising a plain bearing, notably a spiral groove bearing, which comprises a bearing shaft and a bearing shell which encloses the bearing shaft, contains essentially molybdenum and/or tungsten or alloys thereof, and consists of at least two bearing shell portions, a liquid lubricant being present between the bearing shaft and the bearing shell. The material consumption and the manufacturing effort for the bearing shell are reduced in that on the outer side of the bearing portions there are provided connection elements which consist of a weldable material, and that the connection elements are connected to one another by way of a welded joint.

Abstract: An X-ray tube, comprising a cathode arrangement which includes an electron emitter connected to supporting pins which in turn are connected to the cathode structure via a respective fixing element. Particularly simple adjustment of the position of the filament is achieved in that the fixing elements are connected to the cathode structure in a first region and to the associated supporting pin in a second region which is remote from the first region, and that the fixing elements comprise a deformation zone between the first and the second region, deformation of said zone enabling adjustment of the position of the electron emitter relative to the cathode structure.

Abstract: An anode of a rotary-anode X-ray tube is connected to a bearing portion which is rotatable about an axis of rotation and which cooperates with the stationary bearing portion in which there is provided a cavity which extends in the direction of the axis of rotation and whose side walls can be cooled by means of a cooling medium. Effective cooling, in combination with a small pressure drop of the cooling medium, is achieved in that there is provided a cooling member which serves to produce an essentially laminar cooling medium flow and which consists of a number of lamellae which extend essentially parallel to the axis and which are in thermal contact with the side walls of the cavity.

Abstract: A cathode for an X-ray tube including an emitter and a cap of a ceramic material such as Al.sub.2 O.sub.3 surrounding the emitter and having an open part surrounding an exit portion of the emitted electron beam.