Abstract: A centrifuge rotor having an internal chamber in which are mounted a plurality of swinging centrifuge tubes containing fluid samples. Located within the rotor chamber is a liquid support medium which minimizes the amount of stress experienced on the centrifuge tube and at the pivotal junction of the tube with the rotor. The unique arrangement of having the buoyant force of a liquid within the rotor provides support to the tubes when the tubes have pivoted to their position during operational speed. The liquid support is designed to reorient in response to centrifugation in order to automatically provide the buoyant force to the tube during centrifugation and thereby reduce or greatly minimize the strength necessary in the mechanical design and construction of the support elements for the swinging tubes or containers.

Abstract: A rotor seat which automatically adjusts its position with respect to the rotor in response to air flow levitation air entering between the rotor and the rotor seat. The central portion of the rotor seat which has a mating design with the design of the bottom of the rotor is free to move in a vertical direction toward or away from the rotor in response to the flow of air. The rotor seat maintains its optimum position relative to the rotor, allowing the rotor to decelerate in a stable manner.

Abstract: A rotor for a centrifuge including a symmetrically shaped rotor body adapted for rotation about its axis and including a suitable cavity for receipt of samples to be centrifuged. The rotor body is provided with means adapted to cooperate with a centrifuge driving means for rotating the rotor body abouts its axis for centrifuging liquid samples in the cavity. The rotor body is provided with an annular shoulder formed around the top of the rotor and surrounding the opening to the sample cavity, the shoulder having an inward facing surface adapted to receive a thin flexible disc having a bowed shape in the direction of the opening to the cavity so that the edge of the disc seats against the annular shoulder. In its preferred form the disc has a diameter greater than that of the annular space bounded by said shoulder and is bowed by a force against the center portion of the disc causing it to flex in the downward direction thereby assuming a "dish-shape" covering the opening to the cavity of the rotor body.