GB743868A - Improvements in or relating to pumps - Google Patents

Abstract

743,868. Centrifugal pumps. DAVIS FOUNDATION. Inc., J. A. May 26 1953, No. 14638/53. Class 110(1) A iiquid pump comprises an impeller chamber 1 contracting at one end towards an inlet 11, a stator chamber 8 of greater length than the chamber 1 and connected to the larger end of the latter, as by bolts 8a, a substantially conical impeller 4 with spiral vanes 5 surmounted by a shroud 5a; and a core 8b within the chambers 8, with' stator vanes 8e between the core and chamber, the area of flow through the impeller and stator passages being substantially constant throughout the length of the passages. The vanes 8e are curved over about half their length to substantially the reverse of the curvature of the outer ends of the vanes 5 and are substantially parallel with the axis of the chamber 8 over the remainder of their length. The outer surface 4x of the impeller 4 is not truly conical but is slightly convex in axial section. The shroud 5a is bevelled at 5b to provide a clearance 10a with respect to a corresponding shaped ring 10. The movement of liquid through the impeller passages has an ejector effect at the clearance 10b, whereby sand, grit or other sediment which has passed through the clearance 10a is carried away. Two inlet pipes 12 are shown, but one or more than two may be provided. A valve may be provided at the discharge 8d for varying the flow through the pump.