GB1071266A - Liquid-moving unit comprising a centrifugal pump and an electric driving motor therefor - Google Patents

Abstract

1,071,266. Centrifugal pumps. SIGMUND PULSOMETER PUMPS Ltd. Oct. 6, 1964 [Oct. 15, 1963], No.40710/63. Heading F1C. [Also in Division H2] In order to provide lubrication and cooling in a unit comprising a centrifugal pump driven by an electric motor mounted on a common support, which unit may circulate water in domestic and other hot water installations, some of the pumped liquid is circulated from the pump housing 25, Fig. 1, through a filter 46 to a chamber 27 containing the motor rotor 38 and at least some of the bearings, and the liquid is drawn back into the housing by supplementary pump impeller vanes 49. The liquid passes to the chamber 27 through a stopped bore 47 in stationary shaft 29 and is withdrawn through the clearance 44 between the rotor 38 and the wall of chamber 27. It then unites with the main flow which discharges from the housing 25 through one or more ports 23 to a main outlet 21 separated from a main inlet 20 and associated port 22 by cross-webs (not shown). Flow through the port 23 may be controlled by an obturator 24. The filter may be of expanded metal or wire mesh and associated with a deflector 50. The liquid in the chamber 27 cools the rotor and lubricates and cools bearing surfaces between stationary thrust rings 41, 42 and rotary sleeves 35, 36 and between these sleeves and the shaft 29. Terminal connections and electrical leads may be disposed at the outer end of the motor casing 1. In an alternative embodiment, Fig. 2 (not shown), in which the rotor-impeller shaft is rotatably supported in two plain bearings with the impeller overhung, the lubricating and cooling liquid passes through the filter into an axial bore extending the whole length of the shaft, and then through one or more grooves in the inner surface of one bearing, the clearance between the rotor and chamber wall, and one or more grooves in the inner surface of the other bearing to the supplementary impeller vanes.