GB380900A - Improvements in or relating to pumping devices - Google Patents

Abstract

380,900. Rotary pumps. CARTER, M., 20, Balfour Street, BEAN, H. and CAMPBELL, A., (trading as UNIVERSAL VALVE & CHEMICAL ACCESSORIES CO.), Dawson Lane, Dudley Hill, both in Bradford. Aug. 4, 1931, No. 22035. [Class 110 (ii).] In pumping devices of the kind comprising primary and secondary pumps in series wherein the inequality of pressures on the suction and delivery sides of the secondary pump is utilized to vary the effective capacity of the primary pump, the parts are so disposed that an increase of delivery pressure over suction pressure causes an increase in the volume swept by the pistons, blades, vanes or the like of the primary pump, and vice versa. The suction and delivery sides of the secondary pump may be connected to the opposite sides of a piston, diaphragm or flexible bellows, the movement of the latter acting on the primary pump either by mechanical connection or through the medium of a fluid pressure or other form of relay ; or the suction and delivery sides of the secondary pump may be connected to the opposite sides of a moving part of the primary pump. According to Fig. 3 the delivery and suction sides of the secondary pump are connected to the upper and lower sides respectively of a piston 3 which is connected by a link 10 to a ring 4. The ring 4 is pivoted to the casing 1 at 6 and is eccentrically disposed in relation to a rotor 5 carrying spring-pressed blades 7, the eccentricity being varied by the movement of the piston 3. A dashpot 13 forming a loose fit in the hollow upper side of the piston 3 is provided or alternatively, two spring-loaded blades fitted in the body of the pump may bear on the outer face of the ring 4 at the two opposite horizontal points thereof. According to a modification, Fig. 5, the piston 3 has a serrated face constituting a rack which engages a pinion 14 mounted on a sleeve 15 threaded in the casing 1 and carrying the connecting link 10 by means of a ball joint. According to a further modification, Fig. 7, the ring 4 has flattened sides which slide in correspondingly formed parts of the casing 1. The space below the ring 4 communicates with the suction side of the secondary pump whilst the secondary pump delivers through passages 12 across the space above the ring 4. The movement of the ring 4 is controlled by a spring 16. The capacity of the secondary pump may be adjustable. A single primary pump may be used to feed a number of secondary pumps.