Automatic sample processing apparatus

Abstract

An automatic sample preparation apparatus including a centrifuge apparatus for centrifugally separating the lighter components of a sample mixture from its heavier components and an automatic sample loading apparatus which utilizes centrifugal forces to load the sample into a centrifuge drum through an aperture in the bottom end of the drum. A separation chamber in the drum has a truncated conical interior side wall with a trap or cavity therein ringing the wall. The centrifuge drum is spun to force the heavier components into the cavity while the lighter components are forced up the conical interior side wall portion. Means are provided to remove one or both of the components from the separation chamber while the centrifuge drum is spinning to prevent the sample from pouring out of the drum through the bottom aperture. In one embodiment, one of the components is aspirated from the separation chamber by a vacuum source coupled to the interior of the chamber through the hollow shaft on which the drum is spun. Means are also provided for automatically washing sample residues from the separation chamber before subsequent samples are loaded into the chamber. In another embodiment, a plurality of the centrifuge apparatus are mounted on a circular plate rotating in step with a circular tray carrying a plurality of samples from which the samples are initially loaded into the centrifuge drums by the automatic sample loading apparatus. Another circular tray carries a plurality of containers for sequentially receiving the separated component from the centrifuge drum.