GB486108A - Improvements in and relating to bakers' and like ovens - Google Patents

Abstract

486,108. Bakers' &c. ovens. BAKER, B. D., and BAKER PERKINS, Ltd. Sept. 30, 1936, No. 26508. [Class 51 (ii)] In a recirculation heating system for bakers' ovens the arrangement of the heating tubes or conduits is such that a heat gradient in one direction of flow of the gases is balanced or modified by a corresponding heat gradient in the reverse direction, and that there is uniform heating of the oven transversely to the direction of flow. In the arrangement shown the heating arrangements for each half of the length of the oven comprise tubes 18, 20 for top heat and 19, 21 for bottom heat, connected respectively between inlet and outlet headers 3, 3a, 4, 4a: and 7a, 7, 8a, 8, so that the heating-gases flow in opposite directions through the two sets of tubes in each tier. Outlet headers are superposed on inlet headers, and the connecting tubes may cross as shown or may be cranked to bring them into the same horizontal plane for the greater part of their length. Even distribution of gases between the headers and the flues may be promoted by decreasing the cross-section of the headers in the direction of gas flow therethrough, and the quantities of gases flowing in the two directions may be controlled by valves. The reverse flow may be through the adjacent limbs of U-tubes, and in a modification described with reference to Figs. 4-7, (not shown), the heating-system comprises partitioned flat box flues through which the heating-gases flow first on the side nearer the goods space and then on the side remote therefrom.