COUNTING DEVICE FOR FINE PARTICLE

PURPOSE:To remove chocking of pores, by a method wherein, in a Coulter counter, a piezo-electric element is mounted to a side wall at a side which is positioned facing and opposite to a side wall where pores are bored. CONSTITUTION:With a pressure reducing pump 7 started, silver surfaces of a manometer 8 are deflected by a suction action, and a sample liquid 22 in a beaker 23 is fed in a blood cell detecting cell 2 and a pressure reducing pipe 5. A cock 6 is then closed, and the specified volume of the sample liquid 22 is sucked in the cell 2 as a result of the movement of the silver surfaces. The sample liquid 22 passes through pores 33a, and blood cells 21 are detected as a pulse at a detecting circuit 11 by detecting electrodes 34a and 34b. If the fine pore 33a is choked with a foreign matter 43, a choke monitoring circuit 40 detects it, and interrupts an operation of a counting circuit 14, and an AC pulse is generated at a driving circuit to apply it to a piezo-electric vibrator 35. The vibration of the vibrator 35 is propagated to the foreign matter 43 through the sample liquid 22 to flip off the foreign matter 43 from the fine pore 33a.