Patent ID: 9668613
Date: 2017-06-06
CPC Classifications: A21B,A23L,A23V,A47J,F26B

Claim:
1. An apparatus for cooking, heating or drying comprising: a horizontal housing tunnel having an inlet end opening and an outlet end opening; a horizontal heating chamber within the housing tunnel for cooking, heating, or drying; a conveyor which enters the inlet end opening of the housing tunnel, extends through the heating chamber, and exits the outlet end opening of the housing tunnel; upwardly extending right and left side walls of the housing tunnel on opposite lateral sides of the conveyor; upwardly extending right and left side walls of the heating chamber inside of the upwardly extending right and left side walls of the housing tunnel, wherein the upwardly extending right and left side walls of the heating chamber face, and are on the opposite lateral sides of, the conveyor; upwardly extending right and left intermediate side walls on the opposite lateral sides of the conveyor, the right intermediate side wall being positioned between the upwardly extending right side wall of the housing tunnel and the upwardly extending right side wall of the heating chamber and the left intermediate side wall being positioned between the upwardly extending left side wall of the housing tunnel and the upwardly extending left side wall of the heating chamber; upwardly extending right and left inner flow gaps on the opposite lateral sides of the conveyor, the right inner flow gap being formed between the upwardly extending right side wall of the heating chamber and the upwardly extending right intermediate side wall and the left inner flow gap being formed between the upwardly extending left side wall of the heating chamber and the upwardly extending left intermediate side wall, wherein the right and left inner flow gaps have bottom ends; upwardly extending right and left outer flow gaps on the opposite lateral sides of the conveyor, the right outer flow gap being formed between the upwardly extending right intermediate side wall and the right side wall of the housing tunnel and the left outer flow gap being formed between the upwardly extending left intermediate side wall and the left side wall of the housing tunnel; and one or more fuel burners positioned to deliver a combustion gas product into the bottom ends of the right and left inner flow gaps, wherein the heating chamber and the right and left outer flow gaps have bottoms which are closed, the right and left outer flow gaps are spaced apart from the heating chamber by the right and left inner flow gaps, a plurality of right side flow ducts and a plurality of left side flow ducts are provided on the opposite lateral sides of the conveyor, the right side flow ducts have inlet openings in a lower portion of the right side wall of the heating chamber and outlet openings in a lower portion of the right intermediate side wall and extend laterally through a lower portion of the right inner flow gap, the left side flow ducts have inlet openings in a lower portion of the left side wall of the heating chamber and outlet openings in a lower portion of the left intermediate side wall and extend laterally through a lower portion of the left inner flow gap, and the right and left side flow ducts prevent flow from the lower portion of the heating chamber into the lower portions of the right and left inner flow gaps, so that a flow path is defined in the housing tunnel for the combustion products from the one or more fuel burners wherein the combustion products are forced to flow first upwardly through the right and left inner flow gaps, then downwardly through the heating chamber to establish a countercurrent heat exchange flow relationship between the heating chamber and the right and left inner flow gaps, then outwardly through the right and left side flow ducts from the lower portion of the heating chamber to the lower portions of the right and left outer flow gaps, and then upwardly through the right and left outer flow gaps to establish a co-current flow relationship between the right outer flow gap and the right inner flow gap and a co-current flow relationship between the left outer flow gap and the left inner flow gap.