METHOD AND DEVICE FOR COUNTING PARTICLE IN FLUID

PROBLEM TO BE SOLVED: To provide a device capable of accurately and easily counting the number of particles of any given particle diameter and larger by controlling a film thickness of a fluid containing the particles to any thickness through the use of a rotating member and a detecting member interlocked with the rotating member. SOLUTION: Particle counting devices 1 and 1c are provided with a casing 2, a rotating member 32 rotatably arranged in the casing 2 and comprising a smooth surface 33, at least one detecting member 4 arranged in the casing 2 adjacently to the rotating member 32, comprising a smooth protruded surface interlocked with the rotating member 32 to come close to the surface 33 so as to form a fluid passage, and is biased toward the rotating member 32 by a predetermined force, a supporting means 5 to support the detecting member 4, a vibration sensor 71 to detect the vertical vibration of the detecting member 4, and a torque sensor to detect torque exerted on the detecting member 4.