GB469250A - Improvements in the arrangement and construction of electric ovens - Google Patents

Abstract

469,250. Electric ovens. KNATT, J., RUDD, E. W., and WEBB & CO. (ENGINEERS), Ltd., H. Jan. 24, 1936, No. 2307. [Class 39 (iii)] In an electric oven, for example, a baker's oven, the heating elements are detachably housed in metal tubes embedded in filling material and disposed outside the heating chamber in the floor and roof thereof. Figs. 1, 2, show two superposed ovens, the heating chambers 1, 2 of which have a tiled floor 3 and roof 4, the roof tiles 4 being supported as shown in Fig. 2, or in abutting relationship, Fig. 6, by metal T-bars 4a engaging grooves in the tiles and resting at their ends on the fireclay &c. walls 5. Spaces 7, 8 are provided between the roof 4 and floor 3 respectively and a brickwork surround 6, to accommodate transversely disposed metal tubes 9, 10 and heat absorbing packing 11, the tubes at their inner ends being built into the brickwork 6 and being exposed at their outer ends whereby heating elements may be detachably mounted in the tubes and connected in circuit within a recess 12 closed by a cover. The tubes may be spaced more closely near the charging end 13 of the oven. The brickwork 6 is enclosed in a shell 14 of heat insulating bricks, surrounded by ordinary brickwork 15, 16, 17, and ballast 19, 20, a hot water tank 20a being fitted at the top of the structure. In a modification, a portable oven comprises a metal or other inner casing 23, Fig. 5, spaced from an outer metal or other casing 23 by metal supports and slag wool or other heat insulating packing 25. The walls 26 and the floor and roof of the heating chamber are formed of firebrick &c. tiles, the roof tiles being preferably supported by a plurality of metal T-bars 28, Fig. 6, resting at their ends on metal U-bars 27 resting on the side walls of the heating chamber. The metal tubes 9, 10 are positioned by engaging the inner metal casing and embedded in heat absorbing material 11 covered by the slag wool &c. 25. A series of ovens may be mounted one above the other, each oven having a door at one end and a vapour outlet at the other end.