Abstract: The spindle supporting head of a multiple spindle screw machine is intermittently rotated to place its spindles into successively different angular positions about the axis of a spindle drive shaft which extends coaxially into the center of the head. When each spindle is rotatably indexed into a particular angular position, a piece of bar stock is fed through the spindle and projects beyond one end thereof. Each of a plurality of tool slides, which are mounted adjacent the end of the head from which the spindle projects, carries a tool which registers with the stock projecting from an adjacent spindle. The slides are connected to servo motors which are operable by an associated computer to move their tools toward and away from the stock projecting from the associated spindles. Normally the head is secured against rotation by a hirth ring which intermittently is moved from its locking position to release the head so that it can be rotatably indexed.

Abstract: A mixer for liquids and liquid suspensions has a motor drive and housing which is portable and can be carried from tank to tank and attached to the tank where mixing is carried out. The housing depends from the yoke and contains a quill which is driven by the motor drive. A chuck mechanism is associated with the housing and quill to enable mixer impeller shafts to be held in assembled relationship in the mixer and readily removed and replaced with shafts having impellers specially adapted for the particular mixing application of interest. The chuck mechanism is operable even though the quill is hidden in the mixture housing.