PURPOSE: To simplify balance adjustment and to make it possible to change the number of separating stages and separating capacity in response to purposes by a constitution wherein specimen separating pipes are wound around a plurality of rotary shafts which are provided on the concentric circles of the rotary surface of a rotary supporting body at an equal interval.

CONSTITUTION: Rotary supporting plates 3A and 3B are linked and rotated with a horizontal shaft 2 as the center. Rotating shafts 4A and 4B which can be rotated on their axes are horizontally supported at symmetrical positions on the concentric circumference of the rotary surface between the plates 3A and 3B. The supporting plates 3A and 3B are revolved with a rotating motor 5. The shafts 4A and 4B are linked to the plates 3A and 3B with a rotating means and rotated at the same speed. Specimen separating pipes 8A and 8B are made to extend from a specimen introducing/ discharging part 10. The pipes are wound around the shafts 4A and 4B through the shaft 2 and the shafts 4A and 4B and fixed. The pipes are guided to the introducing/ discharging part 10 through the shaft 2 and the shafts 4A and 4B again. A flow-path reversing and switching valve 13 which is provided between the discharging part 10 and the passing position of the shaft 2 switches and connects the flow paths of the separating pipes 8A and 8B in parallel and in series.