HEAT STORAGE MATERIALS AND DEVICES

1,255,331. Thermal storage heaters. ACCESSAIR S.A. 26 Nov., 1968 [27 Nov., 1967; 22 Jan., 1968; 9 April, 1968], No. 56104/68. Heading F4U. In an off-peak heat storage device, the heat storage material comprises host crystals of an inorganic ionic compound which has at least one phase change in the solid state at a defined temperature at which latent heat is released and an additive of dopant crystals which are epitaxial and/or isomorphic, and/or isotypic with a low temp. modification of the host crystal and do not undergo any phase change within the temp. range of operation of the material and wherein neither said compound nor said additive changes to theliquid phase or undergoes any chemical change within the said temperature range. As shown in Figs. 4-6, the heat storage body 40 of a heat storage device consists of a number of cylindrical units 41 pressed from the heat storage material specified above. Air channels 60 occur between the cylinders and a thermal insulation jacket 42 covers the storage unit. A damper 50 can turn on a pivot point 51 in the path of a blower 52. When the device discharges, the damper 50 is in the position shown in full lines in Fig. 5, and air passing through the grille 43 in the direction of the arrow 44 is heated by passing through the channels 60 and then passes through an outlet 46 into the blower and leaves via exit screen 47, the heating element 53 being inactive at this time. During charging, the damper 50 turns into the position shown in dotted lines to block the exit 47, the heating element 53 is switched on, and the heated air circulates to heat up the storage body. An apparatus of this type is also described in Specification 1,244,617.