GB1363816A - Centrifuge and self positioning tube holder thereof - Google Patents

Abstract

1363816 Centrifugal separator AMERICAN HOSPITAL SUPPLY CORP 6 Nov 1972 [31 Jan 1972] 51064/72 Heading B2P In a centrifuge having a rotor 10, Fig. 1, which is selectively rotatable in clockwise and counterclockwise directions about a vertical axis 14 by a motor 13 and which is equipped with circumferentially - spaced holders 11 adapted to support, or formed integrally with, open-topped centrifuge containers 12, each of the holders is pivotable about a horizontal axis and is provided with a weight 21, Figs. 4 and 11, shiftable with respect to the holder between a first position A when the rotor rotates in one sense and a second position C when the rotor rotates in the opposite sense, the weight 21 when in position A urging the holder 11 to pivot the open top of its container 12 inwardly towards the axis 14, Fig. 11, and when in position C urging the holder to pivot the open top of the container outwardly away from the axis 14. Each container may be moulded from plastics or metal and is supported by a pin 16 within a recess 18 of the rotor. The containers or tubes 12 which may be formed of glass or plastics may be removably or permanently mounted in cavities in the holders or may be integral parts of the latter. The weight 21, which may consist of a solid sphere or of particulate material, or which may be a liquid, is movable in an internal J-shaped passage 20 in its respective holder. Instead of the connecting portion 20C between the legs 20A and 20B of the passage 20 being arcuate as shown, it may be of U- shaped or triangular configuration. When the rotor is stationary the weight is in the intermediate rest position B and the tube in the corresponding holder is generally vertical. When the weight is in position A and the tube 12 inclined inwardly as in Fig. 11, a sample of solid material mixed with a washing liquid may be automatically fed to the tube from a manifold chamber 23 in the rotor through a discharge nozzle 24. After filling and centrifuging the rotor 10 is brought to rest and the weight 21 returns to position B. To decant some or all of the liquid from the tube the rotor is rotated counterclockwise so that the weight occupies position C causing the holder to pivot clockwise about the axis of pivot pin 16 until it engages an adjustable stop 25, Fig. 11, and the tube occupies the decanting position shown in Fig. 13.