Rotary driers

Claim 1

AN ARRANGEMENT IN A ROTATABLE DRUM FOR TREATMENT OF A SOLID MATERIAL IN A FLUENT STATE BY EXCHABGE OF HEAT BETWEEN THE MATERIAL AND A GASEOUS MEDIUM, COMPRISING LIFTING BARS EXTENDING SUBSTANTIALLY LONGITUDINALLY WITHIN THE DRUM FOR LIFTING THE MATERIAL DURING ROTATION OF THE DRUM, SAID LIFTING BARS EXTENDING FROM THE CHARGE END OF THE DRUM TO A POINT AT A DISTANCE BEFORE THE DISCHARGE END AND BEING INTERCONNECTED TO FORM A SEPARATE CAGE HAVING AN OUTER DIAMETER SMALLER THAN THE INNER DIAMETER OF THE DRUM, SAID CAGE BEING ADAPTED TO ROLL FREELY IN THE ROTATING DRUM, A SECTOR UNIT BEING PROVIDED IN THE DRUM BETWEEN THE DISCHARGE END AND THE CAGE IN CONNECTION WITH THE CAGE TO FORM ONE ROLLING UNIT THEREWITH, SCREW-LIKE FEEDING BARS BEING SUPPORTED BY THE INNER EDGES OF SAID LIFTING BARS, SAID FEEDING BARS BEING SUBDIVIDED INTO SEPARATE SECTIONS EXTENDING EACH BETWEEN TWO ADJACENT LIFTING BARS, THE FREE EDGE OF EACH LIFTING BAR BEING FORMED WITH SPACED-APART TONGUES OF CONSIDERABLE WIDTH IN THE LONGITUDINAL DIRECTION OF THEIR FREE EDGES, THE SPACES BETWEEN SAID TONGUES HAVING AN INNER EDGE EXTENDING IN THE LONGITUDINAL DIRECTION, SAID TONGUES BEING BENT IN THE DIRECTION OF ROTATION AND ALONG A LINE SUBSTANTIALLY COINCIDENT WITH THE INNER EDGE OF THE SPACES BETWEEN THE TONGUES, THE BENDING ANGLE OF THE TONGUES BEING SUCH THAT THE TONGUES EXTEND SUBSTANTIALLY IN A TANGENTIAL DIRECTION.