Centrifuge unit

A control unit for separating biological substances used in combination with a centrifuge apparatus which includes a motor for rotatably driving a rotor, said control unit comprising:

• force input means for providing operator entry of input data representing a desired level of centrifugal force,
• computation means for calculating motor rotational speed using said input data representing a desired level of centrifugal force,
• memory means for recording and recalling actual centrifugal force as a function of time,
• integration means for integrating said actual centrifugal force over a predetermined time interval of the operational cycle of the centrifuge unit so as to compute an accumulative centrifugal force quantity, and
• display means for visually displaying the computed accumulative centrifugal force quantity.

A method of controlling speed of a motor-driven rotor of a centrifuge unit by utilizing calculation and control means, said method comprising the steps of:

• inputting by operator entry into the calculation and control means input data representing a desired level of centrifugal force for constant speed operation,
• inputting into the calculation and control means input data representing a sample tip radius dimension,
• determining with the calculation and control means, from the input data, a rotational speed for the rotor, and
• setting, by use of the calculation and control means, the speed of the rotor to the determined rotational rotor speed,
• recording the actual centrifugal force during an operation cycle of the centrifuge unit,
• integrating the recorded actual centrifugal force over an interval of time substantially equal to that of the operation cycle, so as to compute an accumulative centrifugal force quantity,
• said recording and integrating utilizing the calculation and control means, and
• visually displaying the computed accumulative centrifugal force quantity.

In combination with a centrifuge apparatus, of the type wherein a housing encloses a motor-driven rotor, for separating biological hazardous substances of varying density, the improvement comprising:

• access means for venting the interior of the housing,
• said access means being capable of an open state when venting is desired and a closed state when venting is not desired,
• said access means being in its open state for venting when said centrifuge apparatus is being operated to clean itself,
• whereby the housing can be vented with said access means in said open state when a sufficient negative pressure exists inside the housing to prevent biological contaminants from escaping.