GB1241539A - Cell-washing centrifuge and method - Google Patents

Abstract

1,241,539. Centrifugal separators; mixing apparatus. AMERICAN HOSPITAL SUPPLY CORP. 4 May, 1970 [27 Oct., 1969]. No. 21283/70. Headings B1C and B2P. Blood cells in the bottom of an open-topped centrifuge tube are mixed with washing liquid by directing a stream of the liquid against the upper portion of the inner surface of the tube while the tube is inclined to, and is travelling about, an axis of centrifugation and simultaneously restraining movement of the tube about its own axis whereby the liquid accelerates under the influence of centrifugal force along the inner surface of the tube from the upper to the lower portion thereof and into forceful contact with the cells to dislodge them and mix thoroughly with them. A cell-washing centrifuge, Fig. 3, comprises a casing 11, a hood 12 and a tube-supporting head 13. The top of the casing is provided with a well 18 in which is disposed the tubesupporting head 13 which is slidably received on a motor-driven shaft 19 to which is fixed a friction drive member 21 in engagement with the underside of the head. The head is provided with tube-receiving recesses 25 each having a vertical outer surface 25a and an inwardly sloping inner surface 25b to permit pivotal movement of each tube 26 between an inclined washing position, Fig. 3, and an upstanding decanting position, Fig. 9. The head is splined to a shaft 30. The hood 12 consists of an arm 31 pivotally carried by a shaft 32 connected to a hood lifting and pivoting mechanism 33 actuation of which is synchronised with the operation of the head driving motor 24 through timing and synchronizing means 36 which also controls the operation of a flow-control valve 16. Fixed to the shaft 30, which is rotatably supported in bearings 37, 38 in the arm 31 is a distributor 39 which is secured to a cover 40. The distributor is formed with an annular chamber 46 to which washing liquid is supplied from a source 13 via a tube 15 and the control valve 16. The chamber 46 has an upwardly and outwardly sloping side wall up which the washing liquid 61, Fig. 7, moves under the action of centrifugal force and passes into passages 50 of circumferentially spaced nozzles 48 projecting downwardly through openings in the cover 40 into the open ends of the tubes. The cover 40 has an internal annular shoulder 54 which engages the upper ends of the tubes 26 when in an inclined position and an outwardly and downwardly inclined undersurface which is slidably engageably with the upper ends of the tubes 26 to permit gradual outward pivoting movement of the tubes under the action of centrifugal force. The cover as part of the hood is slowly raised during rotation of the head 13.