GB191511144A - Improvements in and connected with Electric Heaters. - Google Patents

Abstract

11,144. Igranic Electric Co., [Cutler- Hammer Manufacturing Co.]. July 31. Resistances for heating. Resistance strips are secured by bending over them flexible metal strips which are welded to a plate or member forming part of the body to be heated. Fig. 1 shows the parts before assembling in one form. A channel strip 1 is electrically welded to the plate 2, and after inserting a slotted resistance strip 4 with mica strips 3, 5 and a metal coverplate 6, the sides are folded down upon the cover-plate under heavy pressure. Mica spacers may be inserted to position the strip 4. Several strips may be mounted closely side by side to cover a larger area. In the modification shown in Fig. 25, the folded portions of the channel strip 31 are welded to a cover-plate 36 of substantial thickness. In another modification, Fig. 34, the resistances are held between adjacent strips 46 welded to the plate 47. In a further modification, an annular strip 38, Fig. 27, is welded to a disk 37 for use as a stove or hotplate. The plate or member 2 may be of substantial thickness; for instance, the strips may be welded directly to the inner or outer surface of a pipe or roll. Or the plate may be thin to enable it to be bent round a curved surface; for instance, the plate and heaters may be clamped upon a pipe, or mounted in the form of a hoop or helical winding upon the pipe. Or separate plates may be applied to each side of a box 18, Fig. 13, channel, or other structure. The heaters may be enclosed in a water-tight cover welded along the edges; Fig. 30 shows a heater of this kind suitable for immersion.