GB190811128A - Improvements in Electric Heating Apparatus - Google Patents

Abstract

11,128. Hankin, M. May 27, 1907, [date applied for under Section 91 of Patents &c. Act, 1907]. Resistances for electric heaters are formed with a granular core b separated from an enclosing metal tube a by an envelope c o f material of similar composition but of greater specific resistance than that of the core. Terminal rods e enter the core b at each end, and are carried by, but insulated from, metal caps d, screwed over the ends of the tube a and containing a layer g of material of similar composition to the envelope c. A mixture of powdered cast iron or other metal with fire-clay, plumbago, asbestos, or the like, may be made into a paste with water and packed closely into the tube, the proportion of conducting-material being reduced for the outer layer or envelope c. The Specification in the original form, as open to inspection under Section 91 (3) (a), comprises also a composition of 100 parts by weight of refractory earth, 100 parts of cast iron, and 10 parts of plumbago for the core, and, for the envelope, 100 parts of refractory earth, 25 parts of cast iron, 10 parts of plumbago, and 1 part of asbestos, which after being packed in the metal case is heated gradually to a high temperature and is converted into a compact mass. This subject-matter does not appear in the Complete Specification as accepted. Specification No. 24,517, A.D. 1902, is referred to.