Mixing devices

Claim 1

IN A MIXING DEVICE FOR MIXING AND KNEADING SUBSTANCES AND COMPRISING A MIXING VESSEL TO RECEIVE SAID SUBSTANCES HAVING A FRUSTO-CONICAL SIDE WALL WITH A SUBSTANTIALLY VERTICAL CENTRAL AXIS AND INCREASING A DIAMETER IN THE UPWARD DIRECTION AND A BOTTOM WALL, A MIXING MEMBER IN SAID VESSEL HAVING A LONGITUDINAL SHAFT WHICH IS INCLINED WITH RESPECT TO SAID VERTICAL CENTRAL AXIS OF THE VESSEL, MEANS CARRIED BY SAID BOTTOM WALL OF THE VESSEL SUPPORTING THE LOWER END OF SAID SHAFT, AND DRIVE MEANS AT THE TOP OF SAID VESSEL SUPPORTING THE UPPER END OF SAID SHAFT AND BEING OPERATIVE TO EFFECT ROTATION OF SAID MIXING MEMBER ABOUT THE AXIS OF SAID SHAFT AND SIMULTANEOUS REVOLVING OF SAID MIXING MEMBER ABOUT SAID VERTICAL CENTRAL AXIS OF THE VESSEL WITH THE OUTER PERIPHERY OF SAID MIXING MEMBER, ALONG ITS ENTIRE LENGTH, BEING MAINTINED AT A CONSTANT DISTANCE FROM SAID SIDE WALL OF THE VESSEL; THE IMPROVEMENT CONSISTING OF FIRST AND SECOND CONVEYING MEANS FIXEDLY MOUNTED ON SAID SHAFT AT DIFFERENT RADIAL POSITIONS WITH RESPECT TO THE LATTER AND BEING OPERATIVE, UPON SAID ROTATION OF THE MIXING MEMBER, TO CONVEY SUBSTANCES IN SAID VESSEL LONGITUDINALLY ALONG SAID SHAFT IN OPPOSED DIRECTIONS THROUGH FIRST AND SECOND COAXIAL, ANNULAR ZONES, RESPECTIVELY, WHICH ARE LONGITUDINALLY COEXTENSIVE ALONG SAID SHAFT, SAID FIRST CONVEYING MEANS HAVING A GREATER CONVEYING CAPACITY THAN SAID SECOND CONVEYING MEANS SO THAT THE FLOW RATE OF SUBSTANCES CONVEYED THROUGH SAID FIRST ZONE IN ONE LONGITUDINAL DIRECTION IS GREATER THAN THE FLOW RATE OF SUBSTANCES CONVEYED THROGH SAID SECOND ZONE IN THE OPPOSITE LONGITUDINAL DIRECTION, THE VOLUME SWEPT BY SAID FIRST AND SECOND CONVEYING MEANS UPON ROTATION OF SAID MIXING MEMBER BEING SUBSTANTIALLY LESS THAN THE VOLUME OF SAID VESSEL SO THAT SUBSTANCES IN THE VESSEL ARE DRAWN INTO, AND CONVEYED THROUGH SAID FIRST ZONE FROM ONE END OF THE MIXING MEMBER AND ONLY A PART OF THE SUBSTANCES CONVEYED THROUGH SAID FIRST ZONE IS RETURNED THROUGH SAID SECOND ZONE TOWARD SAID ONE END OF THE MIXING MEMBER WITH THE REMAINDER OF SAID SUBSTANCES CONVEYED THROUGH SAID FIRST ZONE BEING DISCHARGED FROM THE MIXING MEMBER TO MINGLE WITH SUBSTANCES IN SAID VESSEL OUTSIDE OF SAID VOLUME SWEPT BY THE FIRST SECOND CONVEYING MEANS.