| 摘要 |
PURPOSE:To simplify installations for the rotary anode device of an X-ray tube and achieve effective prevention of stains of a rotary anode attached to the end of the rotor of a turbo molecule pump by cooling the rotary anode by means of an oil with a low vapor pressure and installing the whole path of a cooling-oil-circulating system in a vacuum area including the exhaust chamber of the turbo molecule pump. CONSTITUTION:In a turbo molecule pump 1, a rotor 2 is fixed to the top end of a rotary shaft 5 rotationally driven by a high-frequency motor 4 at an ultrahigh speed. The top opening of a housing 11 is closed with a ceiling plate 13. Adjacent to one end of the rotor 2, an ultrahigh vacuum chamber 14 surrounding a rotary anode 3 is provided. Adjacent to the other end of the rotor 2, an exhaustion chamber 17 connected to an auxiliary vacuum pump 16 through an exhaust system path 15 is provided. In addition, adjacent to the lower surface of a base frame 8, a lubricant oil (A) stored in the oil tank 18 is supplied to bearings 7 and 9 after being caused to pass through a suction nozzle 19, an oil supply hole 21 which is installed in the center of the rotary shaft 5 continuously with the suction nozzle 19 and small holes 22 and 23 branching from the oil supply hole 21 in that order. The lubricant oil (A) after passing through the bearings 7 and 9 are returned to the oil tank 18 either directly or through a return port 24. |
