Tobacco curing apparatus

Claim 1

APPARATUS FOR HEATING AN ENCLOSED SPACE, COMPRISING: (A) AN OUTER CASING HAVING OPPOSITE CLOSED END AND SIDE WALL MEANS; (B) AN OPEN ENDED INNER CASING WITHIN SAID OUTER CASING AND HAVING SIDE WALL MEANS SPACED FROM THE SIDE WALL MEANS OF THE OUTER CASING AND COACTING THEREWITH TO DEFINE (1) A CHAMBER BETWEEN SAID INNER AND OUTER CASINGS, EXTENDING LENGTHWISE FROM END-TO-END OF THE INNER CASING AND HAVING OPEN COMMUNICATION WITH THE OPPOSITE END PORTIONS OF THE INTERIOR OF THE OUTER CASING, (2) THE OPPOSITE ENDS OF THE INNER CASING BY VIRTUE OF THEIR OPEN ENDED CONDITION BEING IN OPEN COMMUNICATION WITH THE END PORTIONS OF THE INTERIOR OF THE OUTER CASING; (C) MEANS ADJACENT TO ONE END OF THE INNER CASING PROVIDING AN AIR INLET INTO THE OUTER CASING TO ADMIT AIR INTO THE INNER CASING AT SAID END THEREOF AND ALSO INTO THE ADJACENT END OF SAID CHAMBER BETWEEN THE INNER AND OUTER CASINGS TO TRAVEL THROUGH IT TOWARD AND INTO THE OPPOSITE END OF THE INNER CASING; (D) A RECIRCULATION DUCT CONNECTED WITH THE OUTER CASING AT SAID AIR INLET MEANS AND CONNECTABLE WITH THE INTERIOR OF THE ENCLOSED SPACE TO CONVEY AIR FROM SAID SPACE TO SAID INLET MEANS; (E) A FUEL BURNER HAVING A NOZZLE ARRANGED TO DISCHARGE ITS FLAME AND PRODUCTS OF COMBUSTION INTO THE INNER CASING; (F) A BLOWER IN THE APPARATUS, SAID BLOWER HAVING (1) AN INLET IN OPEN COMMUNICATION WITH THE INTERIOR OF THE INNER CASING NEAR ONE END THEREOF AND AT A ZONE REMOTE FROM THE POINT AT WHICH THE BURNER NOZZLE DISCHARGES INTO THE INNER CASING TO RECEIVE SAID PRODUCTS OF COMBUSTION AND THE AIR WHICH ENTERS THE INNER CASING AND IS HEATED THEREIN; AND (G) A DISCHARGE DUCT LEADING FROM THE OUTLET OF THE BLOWER AND TO THE EXTERIOR OF THE INNER CASING AND PASSING THROUGH AN OPENING IN THE SIDE WALL MEANS OF THE OUTER CASING TO BE CONNECTABLE WITH THE INTERIOR OF THE ENCLOSED SPACE, (1) THE SIDE WALL MEANS OF THE INNER CASING BEING UNINTERRUPTED, OF SUBSTANTIALLY UNIFORM LENGTH AND SUBSTANTIALLY IMPERFORATE AT LEAST FOR THE LENGTH THEREOF WHICH EXTENDS FROM A POINT SUBSTANTIALLY IN LINE WITH THE INLET OF THE BLOWER TO THE REMOTE END OF THE INNER CASING SO THAT THE AIR WHICH ENTERS SAID CHAMBER AT THE END THEREOF REMOTE FROM THE BLOWER CANNOT REACH THE INTERIOR OF THE INNER CASING AND THE INLET OF THE BLOWER EXCEPT BY TRAVELING THE FULL LENGTH OF SAID UNINTERRUPTED AND SUBSTANTIALLY IMPERFORATE PORTION OF THE SIDE WALL MEANS OF THE INNER CASING.