GB760591A - Improvements in centrifugal pumps - Google Patents

Abstract

760,591. Centrifugal pumps. CLARK, J. B. Oct. 27, 1954 [Nov. 2, 1953]. No. 30184/63. Class 110 (1). In a centrifugal pump of the kind having a conical impeller with spiral vanes, followed by non-rotatable spiral vanes which straighten out the flow of liquid from the impeller and guide it to the discharge outlet, the im-. peller is fast on the shaft of an electric motor enclosed in a cylindrical casing forming the pump body, the casing having fixed spiral ducts and communicating therewith an annular axial passage which delivers the liquid to the discharge outlet. The electric motor is housed in a cylindrical casing 10, Fig. 1, having an outer wall 13 and an inner wall 14 forming an annular axially-extending passage 15 which curves inwardly adjacent the outlot end of the impeller. The passage 15 contains spiral vanes 17 integral with axial vanes 17a, which are followed by axial vanes 15a and by struts (not shown) at the left-hand end of the passage. These struts are followed by correspondingly disposed struts 23c at the entrance to a discharge member 23. The impeller, Figs. 1 and 3, comprises spiral vanes 32 between conical walls 30, 31 and operates within a housing 36 to which is attached an inlet branch 36a. The impeller ducts are preferably of uniform cross-sectional area throughout their length. A sealing ring 38 is prevented from rotating by dowel pins 39 and is held by fluid. pressure in sealing engagement with a flange 37 on the impeller and with an annular bearing face on the inlet branch 36a. A further seal 42 of the carbon-ring type is provided at the rear of the impeller. Creepage of water along the shaft 26 is prevented by a rubber or like slinger ring 45a. Leakage water is drained off through ducts 40a and 40b. The motor leads pass through a passage 45 formed in the discharge member 23.