Conveyor oven

A conveyor oven, comprising

• a cabinet defining an oven tunnel for receiving food products;
• a conveyor for moving food products along a cooking path in said tunnel;
• and
• at least one heating unit situated in said cabinet facing said cooking path, said heating unit including an elongated hot air convection duct substantially coextensive with the width of said oven tunnel with a porous wall facing said cooking path and defining a plurality of openings for directing parallel streams of hot air toward said food products and an IR strip heater substantially coextensive with the width of said oven tunnel juxtaposed with said convection duct with a primary source of input heat energy for said strip heater separate from the hot air in said convection duct and independent thereof;
• and
• means for independently controlling the heat input to said convection duct and the heat energy produced by said IR strip heater.

A conveyor oven, comprising

• a cabinet having walls defining an oven tunnel for receiving food products,
• a conveyor for moving food products along a cooking path in said tunnel,
• a heating unit situated in said cabinet facing said cooking path, said heating unit including a convection duct substantially coextensive with the width of said oven and adapted to exhaust hot air toward food products in said cooking path, and an elongated IR strip heater element substantially coextensive with the width of the oven tunnel arranged alongside and parallel to said convection duct;
• and
• a plate disposed between said heating unit and said cooking path, said plate having apertures for directing hot air from said convection duct towards food products and including a portion between said IR strip heater and said conveyor which is transmissive to IR radiant energy produced by said IR strip heater.

A conveyor oven, comprising

• a cabinet having walls defining an oven tunnel of predetermined length and width for receiving food products,
• a conveyor for moving food products along a cooking path in the direction of the length of said tunnel,
• a first pair of elongated parallel IR strip heaters approximately coextensive with the width of said oven tunnel arranged in opposed relationship on opposite sides of said cooking path, respectively, facing said cooking path, said first pair of IR strip heaters being displaced approximately one-quarter of the length of the oven tunnel from the longitudinal midpoint thereof,
• a second pair of elongated parallel IR strip heaters approximately coextensive with the width of said oven tunnel arranged in opposed relationship on opposite sides of said cooking path, facing said cooking path respectively, said second pair of said strip heaters being displaced from the midpoint in the opposite direction by the same distance as the first pair of heating elements, and
• at least one convection heating duct between the heaters on at least one side of said cooking path having a porous wall facing said cooking path for directing hot air toward the food products.

A conveyor oven, comprising

• a cabinet housing an oven tunnel for receiving food products and a recirculation plenum adjacent to said oven tunnel,
• an internal partition separating said oven tunnel and plenum,
• a conveyor for moving food products along a cooking path in said tunnel,
• a heating unit situated in said cabinet facing said cooking path, said heating unit including at least one convection heating duct substantially coextensive with the width of said oven and adapted to exhaust hot gases toward food products in said cooking path,
• said partition between said recirculation plenum and said oven tunnel having an elongated opening extending the length of said oven tunnel,
• a centrifugal fan operatively disposed in said plenum, said centrifugal fan having a circular inlet,
• a transition mounted in said plenum for connecting said enlongated opening to said circular inlet of said centrifugal fan,
• an elongated auxiliary burner duct,
• a gas burner housed in said auxiliary duct,
• an opening in said transition, said auxiliary duct being connected to said opening in said transition so as to allow exhaust gases from said gas burner to flow directly into said transition, and
• said partition having at least one additional opening forming an inlet to said at least one convection duct,
• whereby, said centrifugal fan draws gases from said oven tunnel and said auxiliary duct into said plenum and recirculates said gases to the oven tunnel via the convection heating duct.

A conveyor oven, comprising a cabinet housing an oven tunnel for receiving food products and a recirculation plenum adjacent to said oven tunnel,

• an internal partition separating said oven tunnel and plenum,
• a conveyor for moving food products along a cooking path in said tunnel,
• upper and lower heating units situated in said cabinet facing said cooking path, each said heating unit including at least one convection heating supply duct substantially coextensive with the width of said tunnel and adapted to exhaust hot gases toward food products in said cooking path,
• said upper heating unit including at least one return duct with an opening facing the cooking path coextensive with the width of said tunnel and extending alongside said supply duct, said return duct leading into said plenum,
• means for heating air in said plenum, and
• forced air means for exhausting air from said plenum into said supply ducts to recirculate convection air.

A method of cooking food products, comprising

• defining an oven tunnel for receiving food products,
• conveying food products along a cooking path in said tunnel,
• blowing hot gases toward said food products moving along said cooking path to effect convective heating,
• exhausting said hot gases from said oven tunnel and recirculating said exhausted hot gases back into said oven tunnel,
• simultaneously transferring energy to said food products with infrared energy from a primary source of input heat energy separate from the hot gases used in said convective heating and independent thereof, and
• independently controlling the heat input to said hot gases used in said convective heating and the heat energy produced by said infrared radiation.

A method of cooking food products, comprising

• defining an oven tunnel for receiving food products,
• conveying food products along a cooking path in said tunnel,
• transferring energy to hot gases within said oven tunnel from the exhaust of a primary gas burner located within said oven tunnel, and
• withdrawing said hot gases from said oven tunnel, combining them with the exhaust from an auxiliary gas burner located outside of said oven tunnel to form combined convection gases and recirculating said combined convection gases to said oven tunnel and directing said combined convection gases toward said cooking path to effect convection heating of food products traveling along said cooking path.

A conveyor oven, comprising

• a cabinet defining an oven tunnel for receiving food products,
• a conveyor for moving food products along a cooking path in said tunnel,
• a lower heating unit in said cabinet below said cooking path, said lower heating unit including at least two spaced elongated forced air convection ducts, each having a plurality of openings facing said cooking path for directing parallel streams of hot air toward the food products, and between said ducts, an infrared (IR) strip heater element substantially coextensive with the width of said oven tunnel;
• and
• a primary source of input heat energy for said IR heater separate from and independent of said ducts,
• said oven operable to heat food products on the conveyor simultaneously by convective energy and infrared radiant energy.