US 2002/0164245 A1 · Pump

Abstract

A pump, comprising: an impeller 1 having blades; and a casing 121 for storing the impeller therein, on an inner surface of which, confronting to the impeller, are formed plural numbers of shallow grooves 124 in a direction of pressure gradient of fluid, around a periphery thereof, wherein the fluid being increased up in pressure by the blades 122 flows within the grooves in a reverse direction, directing to an upstream side, so as to spout out at a place where re-circulations occur when the flow rate is low in amount. Also, an outlet angle of the blade 122 is set to be within a region from 30 degree to 90 degree. Further, preferably, front guide vanes 11 are provided, so that a direction of absolute flow at an outlet of the impeller is directed into an axial direction of the pump at an amount of designed flow rate.

Claims15

Dependent claims

A pump, comprising:

an impeller having blades;
and
a casing for storing said impeller therein, on an inner surface of which, confronting to said impeller, are formed plural numbers of grooves in a direction of pressure gradient of fluid, around a periphery thereof, for connecting between an inlet side of blades and an area on the inner surface of said casing where the blades exist, wherein,
an outlet angle of the blade, being measured from a peripheral direction of the blade of said impeller, is set to be within a region from 30 degree to 90 degree.

1 more element

A vertical shaft pump, comprising:

a pump casing;
an impeller having plural numbers of blades, being provided within said casing;
a delivery bent disposed in a downstream side of said pump casing;
a pump shaft, penetrating through said delivery bent vertically and being attached with the impeller at a lower side thereof;
and
plural numbers of grooves, which are provided on an inner surface of said casing, connecting between an inlet side of said impeller and an area on the inner surface of said casing where the blades exist, wherein said grooves are formed to be equal or greater than 5 mm in depth thereof, while to be smaller than the depth in width of said grooves;
an outlet angle of the blade is set to be within a region from 30 degree to 90 degree;
and
said delivery bent is formed in an oval shape in cross-section thereof, in which difference between inner and outer diameters of a curvature is smaller than width of a flow passage therein, on a cross-section in vicinity of the curvature of said flow passage.

6 more elements

Dependencies are inferred from the claim text.

Pump

Life of this patent

Pump

Life of this patent

Abstract

Claims15