ROTARY ANODE X-RAY TUBE

PURPOSE:To prevent any damage to ball bearings used to rotate the anode target by forming minute cracks resulting from intergranular corrosion on the surface of a fixing shaft for supporting the ball bearings. CONSTITUTION:The anode target 3 of an X-ray tube is attached to a cylinder 4 also working as a rotor and the cylinder 4 is supported by a fixing shaft 7 through angular-contact-type ball bearings 5 and 6. A coil spring 9 and a slider 9 are attached inside the fixing shaft 7 and the cylinder 4 is rotated by applying pressure to the inner side of the ball bearing 6. The entire outer surface 12 of the fixing shaft 7 not only its area touching the slider 9 and the ball bearing 6, is subjected to chemical treatment performed utilizing intergranular corrosion to form minute cracks 13 and then nonvolatile lubricant 14 such as molybdenum disulfide is caused to penetrate the cracks 13. Therefore, it is possible to prevent any damage to the bearings 5 and 6 efficiently by providing it with both lubricative property and shock resistance.