GB574107A - Improvements in or relating to electric heaters - Google Patents

Abstract

574,107. Heating by electric resistances. INGRAM, Sir H. Jan. 3, 1944, No. 66. [Class 39 (iii)] Electric heaters or radiators comprise a homogeneous body of vitreous micaceous insulating material such as that known under the Registered Trade Mark "Mycalex" in which during manufacture of the insulating material from a ground mixture of mica and low fusing- point vitreous material formed into a homogeneous body under pressure and by heating to a temperature below the point of total dehydration one or more resistance elements are totally embedded. Resistance wires or carbon filaments a are wound on a notched thin flat plate or former b, which is then placed within the micaceous mixture to which pressure is applied to form a thin plate e, which is dried and becomes vitreous on heating. The ends of the wires a are connected to copper strip d also embedded in the plate. Small brass pillars are attached to the strips d either before moulding or by perforation of the strip after moulding, to form terminals with screws h. Formers may be connected in the plate by copper strips c. Apertures f are formed in the plate after moulding for suspending or fixing the plate, the sides and corners of which are preferably cut to relieve pressure in the plate. The heaters may form domestic radiators, may be attached to drying cupboards, central heating systems or incubators, used as immersion heaters, for prevention of freezing of water pipes, for cooling systems of automobiles, for defrosting windscreens or prevention of condensation on radio or other apparatus. The surface of the radiator may be ground or decorated by strips on the edges or painted or glazed. The windings form flat parallel wires on one side of the former connected by shorter stretches a' of wire lying on the reverse side between notches. Specification 532,824, [Group V], is referred to.