Abstract: A rotor drive shaft assembly for use in a centrifugation system. The rotor drive shaft has a bearing material configured as a sleeve and mounted on the inside wall of a spindle hub with a clearance existing between the sleeve and a housing that surrounds the lower base of the shaft. When the rotor and hub experience radial displacement at a critical speed, the sleeve makes contact with the housing in order to limit further radial displacement. Alternatively, the sleeve can be mounted on the outside of the housing with the clearance existing between the sleeve and the spindle hub, with the sleeve making contact with the spindle hub at the critical speed in order to limit further radial displacement. In another embodiment, a support tube is provided which surrounds the lower portion of the shaft with a clearance existing between the shaft and the support tube.

Abstract: In a centrifuge rotor assembly, a self-retaining rotor lid which is designed to stay on the rotor even when the lid is not tied down or secured to the rotor. The lid has a lip formed on an outer edge of the major side of the lid that faces the open end of the rotor body. The height of the lip is such that the lip extends beyond the edge of the open end of the rotor body. The lip has a diameter that is nominally smaller than the diameter of the open end of the rotor body, thus establishing a clearance therebetween. The clearance allows easy engagement of the lid to the rotor body, but is small enough to prevent the lid from tilting, which keeps the lid on the rotor even when the lid is not secured during centrifugation.