| 摘要 |
A centrifuge includes a vacuum pump machine configured of an auxiliary vacuum pump and an oil diffusion pump for exhausting gas inside a rotary chamber to outside, in which a rotor rotates at high speed. In the centrifuge, a thermistor for detecting a temperature of oil and an oil surface inside a boiler of the oil diffusion pump is provided inside the boiler, and power of a heater is adjusted with the temperature detected by the thermistor, so that a degree of vacuum inside the rotary chamber is stably reduced from atmospheric pressure to a high vacuum state. Besides, when the heater does not heat, a current is carried through the thermistor for self-heating, and it is determined from variation in a resistance value whether the oil exists or not at a position at which the thermistor 8 is placed. |
