Centrifuge rotor with sample holding means and means for balancing the same

Claim 1

In a rotor having a plurality of compartments evenly spaced around the circumference of the rotor and equidistant from the vertical axis of the rotor, automatic balancing means comprising a spring-loaded weight in each compartment constrained to move only radially, said weights having a volume sufficiently less than the compartment volume, a sample container in each compartment, the relationship among the weight, sample container and compartment being defined by the following equation: r1 - r2 - ( x + (RW/yxbh + 12/2h) tan theta ) wherein r1 is the distance between the center of rotation of the rotor and the radially innermost surface of the compartment, r2 is the distance between the center of rotation of the rotor and the radially outermost surface of the compartment, x is the distance between the radially innermost surface of the sample container and the radially outermost surface of a compartment, b is the width of the compartment, h is the height of the compartment, R is the distance between the center of rotation of the rotor to the center of gravity of the sample container plus sample, W is the total weight of the container and sample, y is the density of the weight, theta is the angle of incline of a surface of the weight with respect to a vertical plane 1 is the distance from the top of the weight to the intersection of the inclined surface, if any, and the radially outward surface of the weight and the angle theta , ranges from 0 to tan 1 (r2 - r1 - x1 ).