Abstract: The invention relates to a rotary-anode X-ray tube which includes a sleeve bearing comprising an inner bearing member (9) and an outer bearing member (8). The inner bearing member itself includes three bearing portions, the first (94) of which takes up the axial bearing forces whereas the second bearing portion takes up the radial bearing forces and the third bearing portion (96) interconnects the first and the second bearing portion in such a manner that the symmetry axis (11) of the first or the second bearing portion can perform a swaying motion about the axis of rotation (10) during rotation of the two bearing members. Adequate bearing capacity is thus ensured even when the axial bearing surfaces do not extend exactly perpendicularly to the radial bearing surfaces.

Abstract: A rotary-anode X-ray tube including a sleeve bearing with a stationary and a rotatable bearing portion having facing bearing faces, at least one of which is provided with a groove pattern, has a lubricant which is liquid at least in the operating condition present between the bearing faces. A reduction of bearing wear is achieved by addition of a solid having a low sliding friction to the lubricant.

Abstract: A rotary-anode X-ray tube, include a sleeve bearing which serves to journal the rotary anode which sleeve bearing has a stationary bearing portion and a bearing portion which is rotatable about an axis of rotation. The two bearing portions cooperate with one another via a lubricant and have bearing surfaces which extend perpendicularly to the axis of rotation in order to take up axial bearing forces. The bearing surfaces changes over into external surfaces which form a lubricant gap between the bearing portions and one of which is provided with a groove pattern.

Abstract: A rotary-anode X-ray tube, having a sleeve beating with a stationary bearing portion and a rotatable bearing portion, one of the facing surfaces of which is provided with a groove pattern, in which a bearing gap formed between the two bearing portions is filled with a lubricant at least at the area of the groove pattern. Gas inclusions can be discharged from the area of the bearing in that in at least one of the two bearing portions, in an area outside the groove pattern, there is provided a filter member which cannot be wetted by the lubricant and via which the bearing gap communicates with the vacuum space of the X-ray tube.

Abstract: A rotary-anode X-ray tube includes a sleeve bearing, notably a helical groove bearing, for journalling the rotary anode. The bearing comprises a stationary and a rotatable bearing portion, a liquid lubricant being present between the two bearing portions and at least one of the bearing, portions being provided with at least one capillary-type lubricant duct. The lubricant duct can be particularly simply formed by imparting to the duct a cross-sectional area which is greater than permissible so as to achieve a capillary effect and by arranging in the lubricant duct a member which can be wetted by the lubricant and which extends over at least a part of the length of the lubricant duct, thus reducing the cross-sectional area of the lubricant duct to such an extent that a capillary effect is achieved.

Abstract: A rotary-anode X-ray tube includes a sleeve bearing having bearing faces which are rotatable relative to one another in a direction of rotation and at least one of which is provided with a pattern of grooves. The service life of such a sleeve bearing can be prolonged by providing the grooves with a recess at their rearmost end, viewed in the direction of rotation.

Abstract: The invention relates to a rotary anode X-ray tube with a sliding bearing, in particular a spiral flute bearing. In the case of such an X-ray tube, the passing of lubricant into the vacuum space of the X-ray tube, filled with a strong electric field in the operating state, is prevented by the surfaces, over which the lubricant reaches the space mentioned, being provided with a coating which can be wetted by the lubricant and forms an alloy with the latter.

Abstract: The invention relates to a rotary-anode X-ray tube comprising a bearing arrangement for the rotary anode having at least two spiral groove bearings. A lubricant decoupling of the bearings adjoining each other is achieved in that the distance between the surfaces of the rotating part and the stationary part in the boundary region between the spiral groove bearings is enlarged.

Abstract: The invention relates to a rotary-anode X-ray tube comprising a sleeve bearing, notably a helical-groove bearing, for journalling the rotary anode in the axial direction, which bearing comprises at least two pairs of bearing surfaces for taking up axial forces acting in opposite directions, each pair comprising two bearing surfaces which are present on bearing portions which are rotatable with respect to one another and which bearing surfaces cooperate via a lubricant, the helical-groove bearing communicating with the vacuum space of the X-ray tube via at least opening. Because at the area between the pairs of bearing surfaces there is provided a lubricant reservoir which communicates with the lubricant in the pairs of bearing surfaces and in the stationary bearing portion there is provided a duct which connects the lubricant reservoir to the vacuum space of the X-ray tube, it is achieved that the bearing will not be damaged in the case of loss of lubricant.