US2074650A - Centrifugal pump - Google Patents

Description

March 23, 1937. wfs. HOLDAWAY CENTRIFUGAL PUMP Filed Jan. 24, 1934 Z'Sheets-Shefl. l

Patented Mar. 23, 1937 UNITED STATES PATENT OFFICE My invention relates generally to centrifugal pumps, and particularly to a centrifugal pump having a runner designed to operate in a conventional type of casing which greatly increases 1 5 the fluid impelling activity of the pump.

It is an important object of my invention to embody in a centrifugal pump runner diverging radial fluid passages havinga Venturi action on the principles of the Daniel Bernoulli theorem,

10 which have not heretofore to my knowledge been utilized in the construction and arrangement of centrifugal pump runners or impellers.

Other objects and advantages of my invention will be apparent from a reading of the following 1:, description in connection with the drawings, wherein for purposes of illustration I have shown a preferred embodiment of my invention.

In the drawings:- g Figure ,1 is a sectional elevational view showing one side of therunner and one of the sections of the casing. a

Figure 2 is a transverse vertical sectional view through Figure 1, taken approximately on the line 2--2.

'25 Figure 3 is an enlarged transverse vertical sectional view taken approximately on the line 33 of Figure 1. v

Figure 4 is an elevational view of a portion of the periphery of the impeller showing the 30 shape of the opening of the fluid passages.

Referring in detail to the drawings, wherein like numerals refer to like parts throughout the same, the numeral 5 generally designates a conventional type of two part casing composed of 35 the inside section 6 and the outside section I. The inside section 6 has an axially extending heavy frame portion 8 having the axial bore 9, an outer end portion of which is reduced in diameter and threaded as indicated by the 40 numeral I0. -Into the threaded outer end portion of the bore9 is threaded a packing nut I I through which the impeller shaft l2 passes rotatably. The-packing nut or gland II is in compressing relation to a packing ring I3 which is forcibly 45 abutted with the adjacent end of the hollow stub shaft I4 in which the squared end l5 of the shaft I2 is fixed.

The outside casing section I has an axial-opening it around which is bolted the flange ll of 50 the suction conduit It. The fastening bolts are designated i9. Peripheral flanges 20, 2| on the inside and outside casing sections, respectively, are fastened together by bolts 22.

Both of the casing sections have the generally 55 circular form indicated in Figure-2 with the tangentially arranged discharge conduit. portion 23. It will be notedthat the circular runner or impeller 24 is arranged eccentrlcally within the casing so that its periphery runs very closely to the upper portion of the interior of the casing 5 adjacent the outlet conduit portion 23, and that the periphery of the runner is spaced at a uni-'- formly increasing distance from the interior of the periphery of the casing, proceeding in a counterclockwise direction, until the maximum 10 spacing is reached immediately adjacent the outlet conduit portion 23.

The runner or impeller 24 is composed of a pair of similarly made sections which are connected by radially and circumferentiallyspaced bolts 25 which are located in the regions between adjacent pairs of fluid passages 26, which are formed by registering recesses 21, 29 in the runner sections 29, 30, respectively. The opposite sides of the runner are slightly beveled in conformity with the bevel of the interior wall of the casing sections, but the outer side of the impeller section 29 has a concave irregularity 3| which creates a greater spacing of this side of the section of the impeller from the interior side wall of the casing 6 than would be afforded by a uniform bevelling of the said side of the impeller section 29. Projecting axially from the outer side of the impeller section 29 is the stub shaft ll whose bore l5 extends completely through the runner 30 section 29 as shown in Figure 2. In this bore extends the squared portion I5 of the runner shaft l2 whose inner end protrudes from the inner side of the runner section 29 and is conically formed as indicated at 32. The conical shaft end protrudesat the apex of a conical formation 93 which is defined by a V-shaped annular recess 34 which surrounds the conical shaft end 32 and defines a portion of the outwardly converging inlet 35 of the fluid passages. It will be noted that the conical shaft, end 32 projects axially beyond the inner side of the impeller section 29 and beyond the plane which passes through the center of the inlet openings 35 of the'fiuid passages 25. V

The impeller section 30 has its outer side slightly spaced from the inner wall of the casing section I by virtue of the provision of an annular shoulder 36 which surrounds the opening IS in the casing section I and against which the outer side of the impeller section 30 bears. Itwill be noted that the outer side of the runner section 30 has an annular neck 31 which projects through the opening I6 and has its radially outward side in bearing relation to the surface of theopening l6. c5

The outer end of the neck 3'! is in bearing relation to the adjacent end of the suction conduit l8 which has a portion arranged radially inwardly and in concentric relation to the opening IS in the casing section I. It will be noted that the outer side of the runner section 29 has a portion immediately adjacent the stub shaft H in bearing relation to the adjacent part of the inner wall of the casing section 6. 10 It will be noted that the upper part of the casing indicated by the numeral 38 is comparatively flat and merges in a'counter-clockwise direction into an oval form indicated by the numeral 29 at the bottom of Figure 2 which continues into and forms the outlet conduit portion 23. It will be noted that the opposite sides of the oval portion 36 bulge beyond the outer sides of the casing, thereby increasing the fluid conducting capacity and decreasing the resistance to the passage of the impelled fluid to and through the outlet conduit portion 23.

The fluid passages 26 taper in cross section radially outwardly from the outward end 40 of the radially outwardly converging inlet portions 35.

The inlet portions 35 are arranged at equally circumferentially spaced intervals, and the mouths .or discharge orifices of the fluid passages designated 4|, which are seen to have an oval form (see Figured) are similarly uniformly circumferentially spaced on the periphery of' the runner or impeller. The mouths are circumferentially displaced in a clockwise direction with respect to the intake orifices 36 of the fluid passages, and the intake orifice and the outlet orifice of each fluid passage 26 is connected by a passage of outwardly increasing cross section having a uniform curvature substantiallyillustrated in Figure 1. The walls of the fluid passages 26 range from circular at the point 40 near the inner end thereof 40 to oval at the mouth ll as shown in Figure 4.

Thus the fluid passages 26 diverge in opposite lateral and opposite circumferential directions from .the point 40 to the periphery of the runner or impeller.

Reference may be had to Text Book on Hydraulics," 2nd Edition, Revised, page 42 and page 79 '(George E. Russell of the Massachusetts In-- stitute of Technology, Henry Holt and Company New York, 1915) for an exposition of the principles underlying the present applicant's use of the Bernoulli theorem in the construction and arrangement of his fluid passages in the runner or impeller shown and described herein. Applicants fluid passages are constructed on the Venturi principle, having walls which diverge radially outwardly in the manner shown. Applicant believes himself to be the first person to apply the principles of the Bernoulli theorem to the impeller of a centrifugal pump, although others may have approached in some respect or accidentally thereto. A true application of these principles to an effective degree has not heretofore been made.

While a standard type of impeller casing has in effect been utilized by me to house my new and improved runner, the combination of these obtains a degree of simplicity and efficiency in a rotary, centrifugal pump not heretofore attained, an improvement of fifty percent or more in capacity being available with no greater power application. Any suitable means of applying rotative power to the outer end of the impeller shaft l2, such as a belt pulley and powered belt (not shown) will be suitable for operating the impeller.

Although I'have shown and described a preferred embodiment of my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in material and structure and arrangement of parts within the spirit of the invention and the scope of the subjoined claim.

What is claimed is:-

In a centrifugal pump, a rotor formed with an axial chamber, said Venturi passages having nonradial portions curving away from the direction of rotation of the rotor, said non-radial portions being located radially outwardly from said flaring mouths.

WILLIAM S. HOLDAWAY.

Images