Abstract: In an improved food freezing tunnel, an improved freezing air flow apparatus, more uniformly distributes upwardly flowing freezing air through a horizontally traveling porous food conveyor, thereby more effectively freezing the conveyed food pieces. The improved freezing air flow apparatus utilizes a centrifugal fan wheel, without a surrounding volute or housing, mounted with its rotational axis arranged vertically. It is dependingly mounted from a fan motor, in turn centrally supported, on horizontal frame, within the fan chamber located over an open bottom lower air souce chamber of the freezing tunnel. Returning air, after passing from the fan chamber up through the freezing coil chamber, and beyond up through the porous conveyor belts of the freezing chamber, is drawn down within the overall freezing tunnel building alongside each side of the freezing tunnel, to be again drawn upwardly through the open bottom air source chamber and then back up into the fan wheel and fan chamber for recirculation.

Abstract: Vibratory weir assemblies, in selected embodiments, are respectively installed in food freezing tunnels to cause at the outset of the freezing operations complete separation of pieces of foods, such as french fries, so they will be individually frozen during the remaining fluidization freezing travel through a food freezing tunnel. Previously prepared foods, such as precooked french fries, moving into a food freezing tunnel on a mesh conveyor, are confronted by a vibrating weir located just above the mesh conveyor. By the time the food pieces are vibrated up and over the vibrating weir each one is free of the other, so subsequently, as they progress on a mesh conveyor, the fluidizing and freezing air circulates completely about them. The vibrating weir is actuated principally up and down with some translatory movement, by using an overhead mechanism having an appearance of modified advancing and shaking mechanisms previously used under shaking tables and/or advancing and shaking conveyors.