GB257169A - Improvements relating to electrically-driven rotary pumps - Google Patents

Abstract

257,169. Drysdale & Co., Ltd., and Young, J. Feb. 10, 1926. Pumping-machines and apparatus.-A rotary pump b and the electric driving motor a on its shaft c are arranged for working in submerged positions, the casing being provided with a valve to prevent the liquid from reaching the motor when the machine is not running. The pump and motor are spaced apart by a hollow cylinder d, and the motor is hermetically sealed except at the gland e where the shaft leaves it. A ring g concentric with the shaft c is secured to a, flange on the cylinder d, and a valve ring h of the same diameter and width as the ring g is supported immediately above it on a flexible disc k, which may be of stainless steel, copper or other non-corrodible metal. The disc is clamped between a nut w on the shaft and an extension v on an electromagnet n. This magnet is energized, when the motor is running, through brushes t, u and slip rings s, r. Its core contains spring-pressed pins p which engage an armature ring m secured to the ring h. When the machines are not running the pins p keep the rings g, h in engagement so that no liquid can reach the motor. When the machines are running, the magnet n is energized and the armature m with the ring h is lifted against the pins p. The liquid is then prevented from entering the cylinder d by a centrifugal repeller 4 rotating with the shaft c and constructed like the impeller of a centrifugal pump.