There is the first storage unit (21), the second storage unit (22) with the blood storage slot (20) of what storage of blood and the third storage unit (23) being connected between the first storage unit of what and the second storage unit and with the first storage unit and the second storage unit is set. Blood storage slot (20) is provided with ripple struction (28). The stroke for changing ripple struction (28) by using ripple adjustment mechanism (83,93), can adjust the volume of blood storage slot (20).用於存儲血液的血液存儲槽(20)具有第一存儲部(21)、第二存儲部(22)、以及設置於第一存儲部與第二存儲部之間並且與第一存儲部及第二存儲部連通的第三存儲部(23)。在血液存儲槽(20)設置有波紋結構(28)。通過使用波紋調整機構(83、93)改變波紋結構(28)的伸縮量，能够調整血液存儲槽(20)的容積。
