Patent GB-191420009-A (GB)
Title: Improvements in or relating to Thermo-piles and Thermo-electric Measuring Apparatus.
Inventor: HAUSRATH HERBERT
IPC: G01J5/12
Filed: 1914-09-21
Granted: 1915-10-21
Abstract: 20,009. Hausrath, H. Sept. 21. Thermo-electric batteries for use in measuring radiation or electric energy. Stacks of thin plates, shown in full lines in Fig. 1, are clamped between the outer ends of the elements, shown by broken and dotted lines; the plates are either of non-conducting material or insulated metal or alternately of conducting and insulating material, the insulating plates being larger than the others, to avoid short-circuits. Adjacent elements may be connected by drops of solder as indicated in Fig. 1. Pins or other pieces passing through holes or notches in the plates fasten them together, the points of contact of conducting-plates with the pins or the like being staggered, for which purpose the pins may be round and the holes square and angularly displaced. A pair of elements may be soldered to a plate of the form shown in Fig. 2, if necessary into a fine groove, the narrow connecting-strips of the plate being removed after the pile is assembled, so that the end pieces form parts of separate stacks. For measuring radiation, the pairs of elements, if of strip form, may be twisted through 180 degrees so that their hot junctions are in one plane. A thin narrow strip may then be cemented along the junctions. In order to avoid inequalities in the rates of heating or cooling of the junctions, three elements may be united to a single strip or the like, arrangements for this purpose being diagrammatically shown in Figs. 5 and 6, where the insulating-plates are indicated by full lines and the conducting-plates are not shown. A temperature-compensation pile may alternatively be used; the two piles may be separate or may be built up between a central stack of plates and each of two outer stacks. A differential arrangement for photometry comprises two piles 5, 6 and 7, 8, Fig. 9, held by two stacks of plates 9, 10 of conducting and insulating material, so that a circuit is completed between the stacks alternately by pairs of elements of the two piles. Between the piles is a screen 11 the faces of which may be reflective. Iron and nickel elements may be used. Interlooped wires, Fig. 4, may be soldered together and loosely twisted over themselves, preferably in opposite directions, to give greater elasticity. The two metals may also be electro-deposited side by side with only slight overlapping on a cathode of polished metal, resin or the like, or glass. The cathode may be dissolved or melted, or the deposit removed mechanically, in some cases after being cut into strips. Two or three sheets of different metals, exceeding 0À1 mm. in thickness, may be soldered together edge to edge and afterwards reduced by rolling, grinding, or both. A welded butt joint may be made by means of a hammer with an electrically-heated platinum strip laid over the joint; this treatment may be applied to one side or both. The sheets may also be electrically welded with a small overlap. Thin bi-metallic sheets obtained by any of these processes may be embedded side by side in a material such as paraffin, and cut simultaneously by a microtome. Very delicate sheets may be cut together with a foundation of metal foil, which is etched away after assemblage of the pile. The complete pile may be protected by a coating of varnish or oxide, or by enclosing it in an inert gas. According to the Provisional Specification, the metals may be deposited by the Schoop squirting process or by cathode spraying.