High speed rotary drum system

Herein disclosed is a rotary drum for use in an ultra-high speed centrifuge. An electrically conductive rotary drum is disposed in an electrically conductive stationary drum through bearings provided at both ends thereof. A mercury brush is disposed in contact with each shaft of the rotary drum so that a current from a DC current source connected to either brush flows through the rotary drum to the other brush connected to the stationary drum to form a closed DC loop through the DC source. A pair of magnets are disposed around the outer diameter of the stationary drum so as to produce a flux transverse to the wall of the rotary drum. If the current flows axially through the rotary drum, it rotates as the rotor of a DC motor. Centrifugal stress is reduced by the effect of the attractive force induced by the current flowing through the rotary drum, and bearing action is developed between the rotary drum shaft and the bearings due to repulsion caused by current flowing through the stationary drum and said bearings. (Ohno, Y.)