GB678516A - Improved assembly for electrical resistance units - Google Patents

Abstract

678,516. Metal grid resistances. LAINE, R. Aug. 23, 1949, No. 21923/49. Class 37. In a resistance grid assembly the grid supporting members are provided with external longitudinal ribs. In Figs. 1 and 2 the individual strips of the grid 3 are formed with external ribs 4, 4<SP>1</SP> which register respectively with the diagonal rib of a top U-shaped channel 1 and with the opposite diagonal rib of a lower U-shaped channel 1<SP>1</SP> so that in the assembly the ribs cross to form an X. The grid strips pass alternately above and under stiffening and supporting metal bars 6, 6<SP>1</SP>, as shown, Fig. 2. The metal bars 6, 6<SP>1</SP> are provided with appropriate diagonal ribs and insulation takes the form of intervening micanite sheets 5, 51 and 7, 7<SP>1</SP>, also having appropriate diagonal ribs. The end grid strips 15, 16 are cut out at 13, 14 so that each has the same section as the remaining grid strips and consequently the same heating with current flow. In Fig. 3, the individual grid strips are secured by clasping members 23 to supporting bars 17, 18, wholly of insulating material or covered with insulating material. The grid strips pass alternately above and under the supporting bars as at 21, 22. Each resistance strip passes through the notch 27, Fig. 4, in the associated clasping member. Specification 657,017 is referred to.