Submersible multistage pump with impellers having diverging shrouds

(19)

(11)

EP 2 025 942 A3

(12)	EUROPEAN PATENT APPLICATION

(88)	Date of publication A3:
	18.08.2010 Bulletin 2010/33

(43)	Date of publication A2:
	18.02.2009 Bulletin 2009/08

(21)	Application number: 08161663.3

(22)	Date of filing: 01.08.2008

(51)

International Patent Classification (IPC):

F04D 1/06^(2006.01)
F04D 29/22^(2006.01)

F04D 13/08^(2006.01)
F04D 29/44^(2006.01)

(84)	Designated Contracting States:
	AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR
	Designated Extension States:
	AL BA MK RS

(30)

Priority:

01.08.2007 US 953386 P

(71)	Applicant: Franklin Electric Co., Inc.
	Bluffton IN 46714 (US)

(72)	Inventors:
	Bookout, Russell Fort Wayne, IN 46807 (US) Volk, James J. Fort Wayne, IN 46814 (US)

(74)	Representative: Newstead, Michael John et al
	Page Hargrave Southgate Whitefriars Lewins Mead Bristol BS1 2NT Bristol BS1 2NT (GB)

(54)	Submersible multistage pump with impellers having diverging shrouds

(57) A centrifugal pump may include plural pump stages (300), each comprising an impeller assembly (304), a stationary disc assembly (306) and a diffuser assembly (302), all disposed about an impeller shaft (102) that is driven by a motor. The impeller assembly (304) may include upper and lower impeller shrouds (338,334) having facing surfaces, and a plurality of impeller vanes (344) extending between the surfaces of the shrouds (338,334) to define a plurality of flow passages (346) for liquid to flow outwardly from a central hub (340) of the impeller assembly (304). To assist in pressure recovery of the pump, the distance between the surfaces of the impeller shrouds (338,334) may increase as the radial distance from the central hub (340) increases.

Search report