GB348146A - Improvements in and relating to mercury vapour rectifiers - Google Patents

Abstract

348,146. Mercury-vapour rectifiers. AKT.-GES. BROWN, BOVERI, ET CIE, Baden, Switzerland. Feb. 7, 1930, No. 4165. Convention date, May 21, 1929. [Class 39 (i).] In an arrangement for reducing the quantity of vapour in front of the anodes by varying the size of the cathode spot e in accordance with the load, by means of a piston l which is operated by the arc current to regulate the flow of mercury in a pipe f between the cathode vessel o and a mercury container g, the vessel o is of conical shape and of such dimensions that there is always only sufficient mercury therein to form a surface corresponding to the size of the cathode spot. As shown in Fig. 1, a copper or iron closing plate c, provided with a cooler d, is secured to the casing by an insulator b, and supports the cathode vessel, which is formed of refractory metal such as tungsten, molybdenum or tantalum, or of heat-conducting metal lined with a refractory metal. To improve heat conduction, a copper layer may be inserted between the cathode vessel and the plate c when the latter consists of iron. The cathode vessel may consist of segmental pieces x and the cooling medium therefor should then consist of mercury. A conical insertion h of quartz or chamotte prevents the cathode spot from wandering to the casing. Condensate is collected in a gutter i and is returned to the pipe f through a pipe k which is provided with a valve n to prevent oscillations in the mercury column. The piston l is controlled by the solenoid m to act on the elastic wall of the vessel g. In a modification, the cathode closing plate consists of a vessel p, Fig. 2, containing cooling mercury, the level of which is higher than that of the cathode. A cooling coil s is mounted in the condensation space of the vessel which may be connected with the interior of the rectifier by a cooled passage ; the vacuumtight joint between the members o, h is then superfluous.