PROBLEM TO BE SOLVED: To reduce damage to the inner surface of a bearing box, by reducing friction between the bearing outer ring and bearing box, upon occurrence of creep phenomenon.SOLUTION: A rotary anode X-ray tube device has a negative electrode releasing thermal electrons, a positive electrode opposed to the negative electrode, and a bearing for supporting the positive electrode rotatably. The bearing has a bearing inner ring connected mechanically with the negative electrode, a plurality of rolling elements arranged on the outer periphery of the bearing inner ring, a bearing outer ring provided farther outside than the plurality of rolling elements, and a bearing box for supporting the bearing outer ring. Surface roughness of the inner surface of the bearing box, facing the outer peripheral surface of the bearing outer ring, is differentiated from the surface roughness of the outer peripheral surface of the bearing outer ring. An X-ray imaging apparatus using the rotary anode X-ray tube device is also provided.SELECTED DRAWING: Figure 7COPYRIGHT: (C)2017,JPO&INPIT【課題】クリープ現象の発生時の軸受外輪と軸受箱との間の摩擦を低減して前記軸受箱内面の損傷を低減すること。【解決手段】熱電子を放出する陰極と、前記陰極と対向配置された陽極と、前記陽極を回転自在に支持する軸受と、を有し、前記軸受は、前記陰極と機械的に接続された軸受内輪と、前記軸受内輪の外周に配置された複数個の転動体と、前記複数個の転動体のさらに外側に設けられた軸受外輪と、前記軸受外輪を支持する軸受箱と、を有し、前記軸受外輪の外周面の表面粗さに対し、前記軸受外輪の前記外周面と対向する前記軸受箱の内表面の表面粗さを異なる表面粗さとした、ことを特徴とする、回転陽極型X線管装置、および回転陽極型X線管装置を用いたX線撮影装置。【選択図】図7
