GB435426A - Improvements relating to electrically operated devices for controlling or regulating the level of liquid or other flowing materials - Google Patents

Abstract

435,426. Regulating liquid levels. EVERSHED & VIGNOLES, Ltd., and NEEDHAM, J. C., Acton Lane Works, Chiswick, London. June 13, 1934, Nos. 17518/34 and 11783/35. [Class 123 (i)] Means for controlling the level of conducting liquid or flowing mater ial in a container com prises two pairs of electrodes a, b and a, c arranged in the neigh bourhood of the highest and lowest levels re spectively the conduct ing paths in each pair being in parallel witl each other and botl paths being in series with the actuating winding of a switch n controlling the stopping and starting of a pump or other device. One electrode such as a may be common to both pairs and may be the wall of a tank, if this be conducting. The electrode assembly may consist of stainless steel electrodes b, c connected by a stainless steel rod insulated throughout its length. The common electrode may be an enclosing tube suitably spaced and insulated from the remaining electrodes. According to the first Provisional Specification each pair of electrodes may consist of a copper tube concentric with an internal copper element. Alternating current is preferably applied to the circuit operating the switch n which comprises a counterweighted lever operable only when both pairs of electrodes are immersed and released only when both are uncovered. If the pump is to fill the tank the starting circuit for the pump is connected to the back contact p, as shown, but if it is to empty the tank, to the contact w. Specification 410,278 is referred to.