GB713653A - An electrically heated muffler for containers - Google Patents

Abstract

713,653. Electric heating muffles. HERON, A. G. June 23, 1952 [July 5, 1951], No. 13282/51. Class 39 (3) A muffle for melting, e.g. paraffin wax or butter in a container, or for drying a container comprises a hollow frame about which is wound an electric heating conductor 9 embedded in refractory insulation in a metal sheath, the muffle being adapted to be passed over the container. The conductor 9, which may be of steel, aluminium or copper embedded in magnesium oxide or silicate and sheathed in metal, is wound in a coil on a former A comprising T-section bars 1 extending between rings 2, 3, crimped wires 10 surrouding the former. A bolt 7 secures spaced inner and outer barrels 8, 13 to a cruciform frame 6 fixed to the ring 2, insulation, e.g. slag wool or fibre glass, being packed between the barrels 8, 13 which are bolted together at their lower ends, a cover 19 being secured to a frame 14 over the open upper end of the barrel 13. A thermostat 18 is provided. For melting thermoplastics, e.g. paraffin wax or butter, the muffle is placed over the container. For drying empty containers the arrangement is as above, but air is circulated by a pump through the container and muffle by means of a vent 20 in the top of the muffle. In a modification, the parts 1, 2, 3, 6 are omitted, a rigid, wire mesh forming the former, which is of similar shape to the first embodiment.