Rotary air lock

Claim 1

A ROTARY FEEDER FOR PARTICULATE SOLIDS COMPRISING A HOUSING HAVING A CYLINDRICAL INNER WALL AND TRANSVERSE END WALLS FORMING A CYLINDRICAL CHAMBER THEREIN, SAID HOUSING INCLUDING AN INLET HAVING AN OPENING THROUGH SAID INNER WALL AND AN OUTLET HAVING AN OPENING THROUGH SAID INNER WALL REMOTE FROM THE OTHER OPENING; A ROTOR MOUNTED IN SAID HOUSING FOR ROTATION IN SAID CHAMBER, SAID ROTOR HAVING A CENTRAL SHAFT AND LONGITUDINAL VANES EXTENDING OUTWARDLY THEREFROM INTO SEALING ENGAGEMENT WITH SAID INNER WALL, MEANS FOR ROTATING SAID SHAFT, AT LEAST ONE SEALING END PLATE BEING TRANSVERSELY MOUNTED BETWEEN AN END WALL AND SAID VANES AND IN SUBSTANTIALLY SEALED RELATION WITH THE INNER WALL AT ITS PERIPHERY WITH PROVISION FOR SLIDING LONGITUDINAL MOVEMENT THEREOF, PLATE RESILIENT MEANS BIASING SAID END PLATE LONGITUDINALLY TOWARD AND INTO COMPLETE SEALING ENGAGEMENT WITH THE END OF THE ROTOR, AND GAS MEANS MAINTAINING GAS UNDER PRESSURE IN THE SPACE BETWEEN THE OUTER SURFACE OF SAID SEALING END PLATE AND ITS ADJACENT END WALL TO INCREASE THE SEALING BIAS AND TO INSURE AN OUTFLOW OF GAS AND THEREBY PREVENT AN INFLOW OF MATERIAL.