Apparatus for coating granules

Claim 1

APPARATUS FOR COATING GRANULES, SAID APPARATUS COMPRISING (A) A HORIZONTAL ROTATABLE CYLINDRICAL DRUM ADAPTED TO HOLD GRANULES AND MOUNTED FOR ROTATION ABOUT A HORIZONTAL AXIS; (B) MEANS FOR ROTATING SAID DRUM; (C) MEANS POSITIONED IN SAID DRUM FOR SPRAYING LIQUID COATING ONTO GRANULES BEING TUMBLED WITHIN SAID DRUM; (D) A NONROTATABLE AIR DUCT CENTRALLY MOUNTED WITHIN SAID DRUM AND EXTENDING THE LENGTH THEREOF; SAID AIR DUCT BEING DIVIDED DIAGONALLY ALONG ITS LENGTH INTO FIRST AND SECOND CHAMBERS; (E) AIR INLET MEANS COMMUNICATING WITH SAID FIRST CHAMBER; (F) AIR OUTLET MEANS COMMUNICATING WITH SAID SECOND CHAMBER; (G) SAID FIRST CHAMBER HAVING A SINGLE SLOT OPENING EXTENDING ALONG ITS LENGTH AND BEING ADAPTED TO DELIVER AIR TO THE INTERIOR OF SAID DRUM AT AN EQUAL VOLUME, CONSTANT TEMPERATURE AND PRESSURE THROUGH SAID OPENING ALONG A GUIDED PATH IN A GENERALLY DOWNWARD DIRECTION ONTO GRANULES BEING TUMBLED WITHIN SAID DRUM; (H) SAID SECOND CHAMBER HAVING A SINGLE SLOT OPENING EXTENDING ALONG ITS LENGTH ADAPTED TO RECEIVE AIR FROM THE INTERIOR OF SAID DRUM; AND (I) GUARD MEANS FOR SAID SLOT OPENING OF SAID SECOND CHAMBER FOR PREVENTING FALLING GRANULUS FORM ENTERING SAID SECOND CHAMBER THROUGH SAID SLOTS OPENING.