US2836124A - Pumps - Google Patents

Description

May 27, 1958 K. R. LUNG 2,836,124

PUMPS Filed Jan. 18. 1955 INVENTOR.

KENNETH R. LUNG ATTORNEYS United StatesPatent O PUNIPS Kenneth R. Lung, Dayton, Ohio, assignor to The Tait Manufacturing Company, a corporation of Ohio Application January 18, 1955, Serial No. 482,605

2 Claims. (Cl. 103-103) This invention relates to centrifugal pumps, and more particularly to an impeller construction for a centrifugal pump and to a rotary seal having simple applicability to impellers for centrifugal pumps. This application is a continuation-iu-part of my applications Serial Number 359,539, filed June 4, 1953, now abandoned, and Serial Number 373,564, filed August 11, 1953, now Patent Number 2,810,346, both assigned to the same assignee as this application.

It is a primary object of the present invention to provide a pump impeller which is of improved and simplified novel construction having special advantages from the standpoints of economical cost of fabrication, mounting in conjunction with the drive shaft in a pump, and also ease and effectiveness of sealing against leakage from the interior of the pump along or around the drive shaft.

An additional object of the invention is to provide a pump impeller which is of such structural characteristics that it is easily fixed on the drive shaft from a position outside the pump casing, and particularly to provide such an impeller in combination with a rotary seal effective between the pump casing and a portion of the impeller itself independently of the drive shaft and thus to insure against possible access of liquid from the pump to the drive shaft.

Another object of the invention is to provide a pump impeller having the above outlined characteristics which includes a mounting sleeve cast integrally therewith and of such proportions as to be receivable on a drive shaft inserted therein from outside the pump casing so that a rotary seal may be located between this sleeve and the pump casing to establish complete protection of the drive shaft and its drive motor from access by liquid from the interior of the pump along the drive shaft.

A further object of the invention is to provide a pump impeller construction including a mounting sleeve as outlined above in combination with a collar receivable over the sleeve portion of the impeller outside the pump casing and carrying a set screw adapted to extend through a radial bore in the sleeve into a keyway or like depression in the drive shaft to lock the impeller both axially and angularly on the shaft.

It is also an object of the invention to provide a rotary seal adapted for use in a centrifugal pump which is of improved and simple construction embodying a minimum of component parts while affording a high degree of assured sealing effectiveness between a rotary part such as a pump impeller and a stationary part such as a pump casing.

Additional objects of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings Fig. 1 is a view partly in side elevation and partly in section showing a centrifugal and jet pump unit incorporating a centrifugal impeller and rotary seal constructed in accordance with the invention;

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Fig. 2 is an enlarged fragmentary view in section as indicated by the line 2-2 of Fig. l to illustrate the details of construction of the impeller and rotary seal; and

Fig. 3 is a section on the line 3-3 of Fig. 2.

Referring to the drawing, which illustrates preferred embodiments of the invention, the electric drive motor 10 is bolted to a mounting bracket 11 which is in turn shown as mounted by additional brackets 12 on a storage tank 13 or other suitable base. The main pump casing 15 is also bolted to the bracket 11 at 16, and it includes an inlet port 17 in the front thereof leading to a pumping chamber 18 within which the centrifugal impeller 24) operates, the back of the chamber 18 being closed by a gasket 21 and the front wall 22 of the bracket 11. The discharge from the pumping chamber 18 is conducted outwardly through volute diffuser passages 23 to the discharge chamber 25 in the forward portion of the casing 15 from which the discharge flow takes place through the outlet indicated at 26 at a pressure controlled by the control valve assembly 27 as described in detail in the above noted application Serial No. 359,539 and my copending application Serial No. 482,606 filed of even date herewith, now abandoned.

This centrifugal pump unit is shown as combined with a jet pump which comprises a housing 30 within which are the jet nozzle 31 and cooperating venturi tube 32,

and the suction line 33 leads to the housing 39 from the well or other source of liquid to be pumped and is provided with the usual screen 34. The jet pump housing 30 is indicated as mounted directly on the centrifugal pump casing 15 with the aid of a suitable gasket 35, it being understood that for deep well installations, the jet pump unit may be connected to the centrifugal pump by suitable elongated pipes as shown in detail in the above noted application Serial No. 359,539. The passage 36 in jet housing 30 connects With a port 37 leading from the discharge chamber 25 to supply the high pressure liquid to the inlet end of the jet nozzle 31 in the usual way. Fig. 1 also indicates a passage 38, which is normally plugged, for connecting to the usual automatic air volume control.

The construction of the impeller 26 and its sealed connection with the drive shaft of the motor 10 are shown in detail in Figs. 2 and 3. The impeller includes an extended sleeve 41) cast or otherwise formed integrally therewith of a single piece. This sleeve fits slidingly over the end portion of the motor shaft 41, which is formed with a keyway 42 or similar slot or depression. The sleeve 40, is of sufiicient length to project rearwardly from within the pumping chamber 18 through the bracket wall 22 for ready access from outside the pump. A col lar 44 fits over this outer end portion of sleeve 40, and this collar 44 carries a set screw 45 proportioned to pass through a radial bore 46 in the sleeve 40 and into the keyway 42, thus locking the impeller both axially and augularly on the motor shaft 41.

In addition to the fact that this impeller construction eliminates possible requirements for boring, tapping or threading operations on the impeller body and/or the motor shaft 41, it prevents the possibility of access by liquid to the shaft 41 from within the pump body, since the end of the shaft is completely shielded within the impeller sleeve. This structural arrangement also facilitates the establishment of a rotary seal where these parts project through the bracket wall 22, and Fig. 2 illustrates a novel form of rotary seal 50 which offers definite advantages of simplicity and effectiveness for sealing the junction between the sleeve 40 and the bracket wall 22.

An important component of the rotary seal 50 is the cup-like element press-fitted into the bore 56 in wall 22 through which the sleeve 40 project and this cup ole ment in clude s an inwardly extending'annular shoulder 57 at the outer end thereofand a flared rim portion58 on its inner end; The cup 55 isfpreferably of brass or other suitably corrosion resistant material so that if the seal assembly should require-replacement, itcan readilybe iremoved and replaced .by a similar cup without complications which are likely to be present when a rotary seal assembly bears tagainst machined surfaces on a housing member, a

a The othenpart of' this' seal assembly includes a statidnary sealing ring 7 60 ,of metal or ceramic which is sealed within the cup 55by'a sealing ring 61 of rubber or like material, 'the sealin'gring '61 bein'gretained in position axially of sleeve 40 by the shoulder, 57 on the cup member '55,'the inner end surface of ring 61 engaging a :c'ircumferentialshoulder 62'on'ring member'60. A ring shapedblock '65 of carbon has a machined surface on its V chiming operations thereon chucking of the bracket with all surfaces which require 7 iouterendfwhichtmates'in rotating sealing engagement indicatedat 6j6.

, with a complementary machined 'surface on the inner {end of the ring member 60,.these machined surfaces being A sleeve 74) of rubber or likematerial includes, a cy- 'lindrical skirt portion 71' at itsouter end which overlies the outer peripheral surface of carbon ring 65 and is compressed into sealing relation with ring 65 by a metal,

I collar 72; This collar 72 includes an inwardly extending skirt portion 73 whchtforms a seat for one end of a "compression spring, 75 having its opposite end seated attits opposite end which is of smaller-diameter propordirectly on. the rear wall of the impeller body. The rubber sleeve 70 also 'includes a cylindrical portion 76 the sleeve and is compressed into sealing relation with V sleeve '40 bya metal-ring 77. The middle portion 78 of sleeve 7t! forms a curving connection between its cylindrical portions: 71 and 76 and is of sufficient axial and radial dimensions to flex to the extent required to maintain the proper, sealing engagement of both end portions of this sleeve with theimpeller sleeve 40 and the carbonring65." V

"Inoperationdhe spring 75 continually urges the carhon-ring 65 into sealing engagement with'the ring mem- "ber 69,,Whl16 'the cylindrical portions 71 and 76 of the rubber-sleeve -70 maintain theirsealing engagement with the outer surfaces of ring 65 and impeller sleeve 401emultiple chucking and machining operations.

because it makes possible machining exposed, and thus eliminates the necessity for considerable importance in promoting economical manufacture of the pump of the invention.

A further important advantage is derived in the operation of the pump from the above described recess in the bracket 11, and this is greatly increased protection of the. rotary seal from abrasive action caused by sand in the water being ,pumped.- More specifically, in

the pump of the invention as shown in Fig; l which is constructed and' intended for mounting horizontally, whenever the pump is'shut down, anysand present within the pumping chamber will settle to the bottom of the chamber, including such sand as may at thetime be presout within the above recess, started, centrifugal action will maintain such sand near thetcylindrical wall of the recess, and since this recess is of sufficiently large diameter to provide an annular:

space of correspondingly large radial dimensions surrounding the rotary seal 50, there will be minimum possibility of abrasive action on any part of the seal by san or other gritty material within the Water.

'While the forms of apparatus herein described eonstitut'e preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise :forms'of apparatus, and that changes ,may be 1 made therein without departing from the, scope of the invention Which is defined in the appended claims.

, What is claimed is: V t t 1. An impeller for use in a centrifugal pump in combination Witha drive shaft having a slot therein, com

prisinga cast impeller body including a portion defining an inlet on oneside of said'body, a sleevecastintegrallyt with said body and projecting therefrom: on the opposite spectively, while the rubberring 61 maintains the seal betweenthe ring and cup 55. Ultimately, the rubber portion 76 is likely to freeze into adhesively sealed rela tio'n 'with the impeller sleeve 40 under the continued radial and circumferential forces effective thereon in use,

while Wear at the, machined surface 66 of'the rings 60' and is compensated for'by exten'sionfof the middle portion'78 of rubber sleeve 70.

This seal is therefore-highly effective while requiring 5 relatively few and simple component parts, and it also is easy to replace by the simple expedient of removing the ing the set screw 45 as described. Thus the advantages of economical cost of production of these parts is enhanced by their practical advantages in use; a Aspointed out in my above applicationSerial No. a 373,564, thebracket 11 includes a cylindricalrecess of' substantial axial depth'which is located directly behind the impeller and forms with the wall 22 an extension of the pumping chamber 18. This recess is-comparatively :largein diameter, :namely' a diameter relatively slightly less than that of the impeller, audits cylindrical wall facilitates chuckingof the bracket for all-necessary-maside thereof from said inlet to be received over said drive shaft, said sleeve being of relatively small radial section and having a radial'bore therein spaced from said body, a collar received over said sleeve in overlying relation with said here, said collar having a tapped radial o through bore of sufiiciently larger diameterrgthan said tapped bore to receive freely 'theret-hr ough a screw threaded'in said tapped bore, a set screw threaded in said tapped bore and extending freely through said through bore for seated engagement in said slot to draw'said sleeve into clamped relation with saidshaft on the opposite side of'saidtshaft from said slot, and said slotbcing dimensioned to, provide cooperating action between the side wallsthereof and said set screw preventing rotational movement of said sleeve on said shaft.

' 2. In a centrifugal pump, the combination of a housing and a bracket'cooperating to form the front and back walls respectively of a pumping chamber, an impeller in said pumpingchamber-including a front portion defining the inlet thereof, means for supporting said ,housing'and bracket in horizontally extending 'positionlo establish the .axis of said impeller in a' substantially horizontal plane, an integral sleeve projecting frorn the ba'ckof. said impeller, said bracket having an opening there throughfor receiving said sleeve, a drive shaft received in said sleeve and having a slot therein, said sleeve having a radially extending bore therethrough located outside said pumping chamber and overlying said slot in said shaft,'. a collar received over said'sleeve and having a tapped radial bore therethrough overlying said bore in said sleeve and of sufficiently larger diameter than said tapped bore to receive freely 'theret hrough a screw threaded in said tapped'bora-a-setscrew threaded in said tapped bore and extending frcely through said bore in said sleeve into seated engagement in said slot drawing said sleeve into clamped relation with saidrshaft on the opposite side of said shaft from said slot, said slot being dimensioned to provide cooperating action between the side Walls thereof andsaidset screw preventing rotational This is of 7 When the pump is re movement of said sleeve on said shaft, said bracket including a substantially flat wall facing said impeller and a cylindrical wall defining a cylindrical extension of said pumping chamber of substantial axial extent, rotary seal means including a part secured in said flat wall and relatively rotatable parts located Within said extension for sealing between said sleeve and said flat wall, and said extension being of a diameter relatively slightly less than that of said impeller and substantially greater than that of said seal means to provide a correspondingly large annular space surrounding said seal means for minimizing possible contact With said seal means of abrasive materials present in the liquid being pumped.

References Cited in the file of this patent UNITED STATES PATENTS 2,291,346 Robinson July 28, 1942 6 Curtis Apr. 10, 1945 Curtis July 10, 1945 Adams Dec. 30, 1947 Lipe et al. Jan. 11, 1949 Jensen Mar. 8, 1949 Stratford et al Sept. 13, 1949 Payne Sept. 16, 1952 Maurey Nov. 18, 1952 Heidegger May 12, 1953 Firth Mar. 27, 1956 FOREIGN PATENTS Great Britain Mar. 6, 1919 Great Britain Oct. 31, 1951 Great Britain Aug. 5, 1953 France June 10, 1953

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