Patent ID: 6893412

Claim:
A platelet collecting apparatus comprising: a centrifugal separator possessing a rotatable rotor having a blood storing space formed therein and an inlet and an outlet both communicating with said blood storing space and centrifugally separating the blood introduced through said inlet inside said blood storing space by virtue of the rotation of said rotor; a first line for allowing the flow of the blood entering said centrifugal separator; a second line for allowing the flow of the blood emanating from said centrifugal separator; a plasma collecting bag connected to said first line and said second line so as to collect the plasma emanating from said centrifugal separator and return the collected plasma to said centrifugal separator; a platelet collecting bag connected to said second line so as to collect the platelets emanating from said centrifugal separator; a blood delivering pump disposed in said first line; and a controller for controlling the operation of said rotor of said centrifugal separator and the operation of said blood delivering pump, wherein said controller is programmed to increase the rotational frequency of said rotor in conformity with-the increase of the volume of erythrocytes in said centrifugal separator during blood collection.