Pump impeller with skirt

Claim 2

A centrifugal pump including a volute casing and an impeller rotatably mounted within said casing, said impeller having an open unobstructed eye at the axis thereof and defined by a spiraling vane curving about the eye, said vane including an elastomer skirt bounded by an elastomer edge which forms a leading edge in the vane, said leading edge extending radially and concavely to define opposite axially oriented extremities, said elastomer skirt being rigidly reinforced in the vane at said opposite axially oriented extremities and being unsupported between said opposite extremities whereby said unsupported portion forms a yieldable throat region which extends from said leading edge along the vane toward the trailing edge of the vane to impart yieldability to that part of the vane which engages the material being pumped.

Claim 3

The pump of claim 1, wherein said volute casing has an outlet which is offset axially with respect to the trailing edge of the vane.

Claim 4

The pump of claim 1, wherein the impeller is closed and includes shrouds on opposite sides of the vane joined to the vane, and said skirt includes another edge which extends from the leading edge of the vane along a side of the vane which substantially parallels the plane of a shroud, said other edge being reinforced in the vane.

Claim 5

The pump of claim 1, wherein the skirt is a detachable element detachably connected in the vane with detachable fasteners securing the skirt where such is reinforced.

Claim 6

The pump of claim 1, wherein the detachable skirt element comprises a rigid skeletal member embedded within elastomer material, and said skeletal member bounds the throat region of the skirt.

Claim 7

A centrifugal pump comprising a volute casing a closed single-vane impeller having an open unobstructed eye rotatably mounted in said casing, Said impeller comprising a rigid body including opposed shrouds and an elongated wall disposed between said shrouds spirally curving about the eye of the impeller, said impeller further comprising an elastomer skirt joined to said wall with the skirt and wall together forming said single vane of the impeller, said skirt having an edge forming the leading edge of the vane which extends across the impeller between the opposed shrouds, said skirt being fastened to said wall adjacent opposite axially oriented extremities of its said edge, said skirt having an unsupported portion between said axially opposite extremities and in a region extending from said leading edge toward the trailing edge of the vane thus to provide a yieldable throat region which is yieldable radially on the impeller being rotated and the vane entering material being pumped.

Claim 8

A centrifugal pump comprising a volute casing a closed single-vane impeller having an open unobstructed eye rotatably mounted in said casing, Said impeller comprising a rigid body including opposed shrouds and an elongated wall disposed between said shrouds spirally curving about the eye of the impeller, said impeller further comprising an elastomer skirt joined to said wall with the skirt and wall together forming said single vane of the impeller, said skirt having an edge forming the leading edge of the vane which extends across the impeller between the opposed shrouds, said skirt being fastened to said wall adjacent opposite axially oriented extremities of its said edge, said skirt having an unsupported portion between said axially opposite extremities and in a region extending from said leading edge toward the trailing edge of the vane thus to provide a yieldable throat region which is yieldable radially on the impeller being rotated and the vane entering material being pumped.

Claim 9

The centrifugal pump of claim 6, wherein said elastomer skirt includes another edge substantially paralleling the plane of a shroud in the impeller, and the skirt is detachably connected to said wall by detachable fasteners including fasteners extending along said outer edge of the skirt.

Claim 10

The pump of claim 7, wherein the detachable skirt comprises a rigid skeletal member embedded within elastomer material, said skeletal member bounding the throat region of the skirt.

Claim 11

The centrifugal pump of claim 6, wherein said volute casing includes an outlet which is offset axially from the trailing edge of the impeller vane, and the casing defines a volute chamber which sweeps in a gradually progressing offset from a region directly outwardly from said impeller to said outlet.