Foreign matter accumulation sensor and vacuum pump

Abstract

[Problem] To provide a foreign matter accumulation sensor capable of effectively detecting the amount of foreign matter accumulation in a small space, as well as a vacuum pump. [Solving Means] A foreign matter accumulation sensor includes: a stator disc 219 and an electrode 252 that are capable of constituting a gas flow path 227 inside a turbo molecular pump in a non-rotating state; a rotating disc 229 that is opposed to the stator disc 219 and the electrode 252 and is capable of constituting the gas flow path 227 in a rotating state; a first conducting wire 254 connected to the electrode 252; and a second conducting wire 256 connected to the stator disc 219, wherein estimation of an amount of foreign matter accumulation is made possible on a basis of a change in electrostatic capacitance between the stator disc 219, the rotating disc 229, and the electrode 252.