GB647400A - Improvements in or relating to guide means for impellers for centrifugal pumps or blowers - Google Patents

Abstract

647,400. Centrifugal pumps and blowers. BUCHI, A. Nov. 3, 1947, No. 29307. Convention date, Nov. 12, 1946. [Class 110(i)] A inlet device for a centrifugal pump or blower comprises at least one funnelshaped annular deflecting vane guiding the fluid from the axial into the radial direction at the entrance to the impeller, the ratio between the radii of curvature and the width of substantially equal parts of the passages formed by the annular vanes being approximately equal for all passages when measured in various axially disposed planes passing therethrough. In one construction, Fig. 7, annular vanes 11, 11<SP>1</SP> are built into the inner part of the impeller, which is fastened to the hub by means of a ring 19. The blades 3<SP>1</SP> of the inner part of the impeller, which extend axially and are curved so as to admit fluid without shock, may be connected to a ring 20 which engages with sealing means 21 and may have protrusions 20<SP>1</SP> which interengage with or are riveted or welded to the impeller disc 1. The ring 20 may be fastened to the outer impeller blades 3. The blades 3<SP>1</SP> may be omitted or replaced by a continuation of the blades 3, and the impeller may be shrouded. In the construction shown in Fig. 9, an annular vane 11, and radial vanes 22 are carried by webs 13. The vanes 22 may be omitted. In the multi-stage blower shown in Fig. 13, annular vanes 11b and 11b<SP>1</SP> are carried by the impeller blading and stationary annular vanes 27<SP>1</SP> and 27" are carried by the stator blading. In a modification, Fig. 14 (not shown), annular vanes giving a deflection of nearly 180 degrees are carried by the stator blading, and project into the eye of the impeller. The casing is split into sections on planes perpendicular to the axis, the size of the annular vanes being such as to avoid fouling the impeller on separation of the casing parts.