Vacuum pump, stator column, base, and exhaust system of vacuum pump

An exhaust system of a vacuum pump, comprising:

• a vacuum pump that has a temperature sensor unit disposed in a purge gas flow path to measure a temperature of a rotating portion, and has a thread groove-type seal for causing at least some of purge gas to flow back toward the temperature sensor unit, the thread groove-type seal being provided on a downstream side of the purge gas flow path in which the temperature sensor unit is disposed;
• a purge gas storage device for storing the purge gas used in the vacuum pump;
• and
• a purge gas supply device for supplying the purge gas stored in the purge gas storage device to the vacuum pump, wherein
• the exhaust system supplies the vacuum pump with the purge gas that satisfies either one of the following conditions at least when the temperature sensor unit measures the temperature of the rotating portion:
• a flow velocity of the purge gas is higher than a flow velocity of an exhaust gas flowing backward in at least a part downstream of the temperature sensor unit, the exhaust gas being exhausted in the vacuum pump;
• and
• pressure of the purge gas around the temperature sensor unit creates an intermediate flow or a viscous flow.