Baking oven

Claim 1

IN A CIRCULATING SYSTEM FOR AN OVEN HAVING A CONVEYOR RUN DEFINING THE BOTTOM OF A BAKING CHAMBER, AND HAVING A HEATING ZONE OF LONGITUDINAL EXTEND; GENERALLY HORIZONTAL PLENUM CHAMBER MEANS IN THE UPPER PORTION OF SAID OVER DEFINING THE TOP OF SAID BAKING CHAMBER, A PLURALITY OF VENTS DISTRIBUTED OVER THE ARES OF SAID PLENUM CHAMBER MEANS PROVIDING COMMUNICATION BETWEEN SAID PLENUM CHAMBER MEANS AND SAID BAKING CHAMBER, A BLOWER SUPPORTED AT THE UPPER PORTION OF SAID OVER BETWEEN THE ENDS OF SAID HEATING ZONE, A COLLECTING CHAMBER IN THE UPPER PORTION OF SAID OVEN, SAID COLLECTING CHAMBER INCLUDING HEADER PORTIONS FORE AND AFT OF SAID BLOWER EXTENDING LATERALLY OF THE WIDTH OF SAID OVEN AT LOCATIONS GENERALLY EQUALLY SPACED FROM THE BLOWER, AND A LONGITUDINALLY EXTENDING CONNECTING DUCT PORTION INTERMEDIATE THE SIDES OF THE OVEN BENEATH AND IN COMMUNICATION WITH THE INTAKE SIDE OF SAID BLOWER, VERTICAL DUCTS ALONG SAID OVEN SIDE WALLS COMMUNICATING AT THEIR UPPER ENDS WITH THE LATERAL SIES OF THE HEADER OF SAID COLLECTING CHAMBER, SAID DUCT HAVING OPENINGS SUPERJACENT THE SIDE EDGES OF SAID CONVEYOR RUN PROVIDING COMMUNICATION BETWEEN THE LOWER ENDS OF SAID VERTICAL DUCTS AND SAID BAKING CHAMBER, AND DUCT MEANS EXTENDING TRANSVERSELY OF THE LONGITUDINALLY EXTENDING CONNECTING DUCT PORTION OF SAID COLLECTING CHAMBER COMMUNICATING WITH THE DISCHARGE SIDE OF SAID BLOWER AND WITH SAID PLENUM CHAMBER MEANS.