US3362338A

US3362338A - Impellers for centrifugal pumps

Info

Publication number: US3362338A
Application number: US522664A
Authority: US
Inventors: Stethem Walter Chapple
Original assignee: SA Armstrong Ltd
Current assignee: SA Armstrong Ltd
Priority date: 1965-01-28
Filing date: 1966-01-24
Publication date: 1968-01-09
Anticipated expiration: 1985-01-09
Also published as: CH435989A; NL6601006A; GB1140334A

Description

Jan. 9, 1968 w. c. s E 3,362,338

IMPELLERS FOR CENTRIFUGAL PUMPS Filed Jan. 24, 1966 IIVI/EA/TDR WALTER (f/APPLE STETHEM ATTORNEYS United States Patent 3,362,338 IMPELLERS FOR CENTRIFUGAL PUMPS Walter Chapple Stethem, Don Mills, Ontario, Canada, as-

signor to S. A. Armstrong Limited, Toronto, Ontario, Canada Filed Jan. 24, 1966, Ser. No. 522,664 Claims priority, application Canada, Jan. 28, 1965, 921,845 4 Claims. (Cl. 103-415) ABSTRACT OF THE DISCLOSURE A single or double stage inlet impeller for a centrifugal pump includes two impeller elements in a back-to-back relationship, the two impeller elements being arranged on 1 This invention relates to an impeller for use in centrifugal pumps and more particularly to an impeller element of one-piece stamped construction.

An object of the invention is to provide an impeller which is eflicient, simple and economical to manufacture.

An impeller constructed in accordance with the invention comprises a one-piece disc having alternately protruding and recessed generally radial folds which constitute fluid channels on both faces of the disc, each of the fluid channels being defined by a pair of opposed side walls and a transverse wall, and the disc having a central opening intersecting the inner ends of the fluid channels to provide inlets for the fluid channels.

Preferred embodiments of the invention are illustrated by way of example in the accompanying drawings, in which:

FIG. 1 is a perspective view of an impeller element forming part of an impeller constructed in accordance with the invention;

FIG. 2 is a perspective view, partly broken away, of a single stage, single inlet impeller constructed in accordance with the invention and having a single impeller element;

FIG. 3 is an elevational view of the impeller of FIG. 2;

FIG. 4 is a perspective view, partly broken away, of a single stage, single inlet impeller constructed in accordance with the invention and having three impeller elements;

FIG. 5 is a perspective view, partly broken away, of a single stage double inlet impeller constructed in accordance with theinvention and having two impeller elements; and

FIG. 6 is a perspective view, partly broken away, of a two stage impeller constructed in accordance with the invention and having two impeller elements.

Referring to FIG. 1, an impeller element 10 comprises a one-piece disc 11 that is formed with alternately protruding and recessed generally radial folds which constitute a set of fluid channels 12 on one face of the disc and another similar set of fluid channels 13 on the opposite face of the disc. The fluid channels 12 are defined by side walls 14 and transverse walls 15, and the fluid channels 13 are defined by the side walls 14 and transverse walls 16. The transverse walls 15 are coplanar, as are the transverse walls 16, and the two planes which respectively contain the

transverse walls

15 and 16 are mutually parallel and are substantially perpendicular to the axis of rotation of the impeller. The side walls 14 are substantially perpendicular to the

transverse walls

15, 16. A central opening 17 intersects the inner ends of the

fluid channels

12, 13 to provide a series of radially disposed inlets 18 of generally rectangular shape. The side Walls 14 are curved and they diverge outwardly from the inlets 18 in a spiral configuration to terminate at their outer ends at outlets 19 which are of considerably larger area than the area of the inlets 18, so that fluid velocity head at the inlets 18 will be converted to fluid pressure head at the outlets 19.

The impeller element 10 can be combined with a front plate 20- and a back plate 21 (see FIGS. 2 and 3) to provide a single stage, single inlet impeller. The front plate 20 is secured to the transverse walls 15 and it closes the fluid channels 13 except for their inlets and outlets; the front plate 20 has a central aperture 22 bounded by a cylindrical flange 23, and the aperture 22 communicates with all the inlets 18 to provide a suction inlet for the impeller. The back plate 21 is secured to the transverse walls 16 and it closes the fluid channels 12 on the opposite face of the disc, except for their inlets and outlets; the back plate 21 is provided with a central hub 24 having a threaded bore 25 for attachment to a motor shaft (not shown).

FIGS. 4, 5 and 6 show various other forms of impellers having a plurality of impeller elements 10.

The impeller of FIG. 4 comprises three impeller elements that are secured together back to back to provide fluid channels 26 of increased capacity, and it will be noted that the fluid channels 12 of one disc are aligned with the fluid channels 13 of an adjacent disc. Like the impeller of FIGS. 2 and 3, this assembly of impeller elements is provided with a front plate 20 and a back plate 21. In a similar manner, other numbers of impeller elements can be combined together to provide an impeller of the desired capacity.

A single stage double inlet impeller is shown in FIG. 5, and it includes two impeller elements in a back to back relationship, the two impeller elements being arranged on opposite sides of a flat, circular center plate 27. At both its opposite ends the assembly is provided with a front plate 20, and thus the impeller has two suction inlets each communicating with the inlets of the impeller element (or elements) on the near side of the center plate 27 but not with the impeller element (or elements) on the opposite side of the center plate 27. A central hub 28 having a threaded bore 29 is provided on the center plate for attachment to a motor shaft. For balance, it is preferable to have the same number of impeller elements on each side of the center plate.

All the above described impellers are of the single stage type. An example of double stage type is given in FIG. 6 which shows an impeller that is substantially the same as the impeller shown in FIG. 5 except that center plate 30 is of larger diameter than the impeller discs. The housing (not shown) within which the impeller is to be placed is so arranged that fluid which enters suction inlet 31 is expelled through outlets 32, flows around the center plate 30, thence through suction inlet 33 on the opposite side of the center plate, eventually to be expelled through the outlets on that side; the path of the fluid is indicated by a series of arrows.

The impeller elements can be formed from any material possessing sufficient strength and which is capable of being stamped or otherwise conveniently formed, such as cold rolled steel, brass, stainless steel and aluminum. The various component parts of the impeller can conveniently be secured together by spotwelding, silver soldering or like methods.

Although the impellers described herein are intended for use with relatively incompressible fluids, such as water, it is to be understood that principles of the invention can be applied to impellers suitable for use with compressible fluids, such as air.

What I claim as my invention is:

1. An impeller, a plurality of one-piece discs positioned coaxially, each disc having alternately protruding and recessed generally radial folds which constitute fluid channels on both sides of the disc, each of the fluid channels being defined by a pair of opposed side walls and a transverse wall, and each disc having a central opening intersecting the inner ends of the fluid channels to provide inlets for the fluid channels, a front plate secured to the outer face of one end disc to close the fluid channels of said outer face except for their inlets and outlets, said front face having a central aperture in communication with the fluid channel inlets to provide a suction inlet for the impeller, and a back plate secured to the outer face of the opposite end disc to close the fluid channels 20 of said outer face except for their inlets and outlets wherein the discs are arranged in two groups on either side of a center plate so that the fluid channel inlets of each group communicate with each other but not with those of the other group, and wherein the back plate has References Cited UNITED STATES PATENTS 929,129 7/ 1909 Harder 230-434 2,486,619 11/ 1949 Truxler 230-134.45 2,802,620 8/1957 Darrah 230134 2,899,129 8/1959 Schwaiger 230-134 FOREIGN PATENTS 192,822 12/ 1907 Ger-many. 368,563 2/ 1923 Germany.

419,252 11/ 1954 Great Britain.

HENRY F. RADUAZO, Primary Examiner.