US2272906A - Centrifugal pump - Google Patents

Description

CENTRIFUGAL PUMP Filed Jan. 12,' 1940 2 Sheets-Sheet l 5%4 Mafia ATTORNEY Feb. 10, 1942. L. E. DA coL CENTRIFUGAL PUMP Filed Jan. 12, 1940 2 Sheets-Sheet 2 INVENTOR LAWRENCE EUGENE DAC ox.

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ATTORNEY Patented Feb. 10, 1942 CENTRIFUGAL PUMP Lawrence Eugene Da Col, San Francisco, Calif., assigner to Fairbanks, Morse & Co., Chicago, lll., a corporation of Illinois Application January 12, 1940, Serial No. 313,504-

(ci. 10s-@5) 1 Claim.

My invention relates to pumping equipment and more particularly to improvements in well pumps of centrifugal type.

An object of my invention is to provide a combined pump and injector unit comprising a centrifugal impeller assembly and injector means directly associated therewith, the latter of which serves to increase the suction pressure of the unit whereby to render the same especially appiicable for well pumping purposes. More speciiically, an object of the invention is to provide a highly eflicent unit of this character which is compact and economical of manufacture.

With the foregoing and other objects in view, the invention resides in the novel features of form, construction, arrangement' and combination of parts presently described and pointed out in the claim.

In the accompanying drawings,

Fig. 1 is a side elevational view, partly in section, showing a presently preferred embodiment of my invention;

Fig. 2 is a transverse sectional view taken at line 2 2 of Fig. 1, and

Fig. 3 is a transverse sectional view taken at line 3-3 of Fig. l.

Referring now 4to the drawings -by characters of reference, I designates a motor of appropriate type and power rating having a shaft 3 on the outer end of which is mounted a centrifugal impeller 4. 'Ihe impeller casing or volute is of transversely split construction, one part thereof comprising the end wall 5 of a substantially annular bracket 6 by which the pump assembly is detachably secured to the end bell l of motor I. f

Securement of bracket 5 to the motor is effected by bolts, one of which is indicated at 8, Fig. 1, which extend through recesses formed in an inwardly directed end ange 9 at the inner end of the bracket 6 for threaded engagement with the motor housing, the bolt heads being rendered accessible through windows IU formed in the bracket 5. A re-entering sleeve l2 formed integrally on end wall 5 of the bracket 6 encases suitable packing means, (not shown), for checking leakage along the pump shaft. An opening i3 at the bottom of the bracket 6 affords a drain passage for leakage iluid.

The centrifugal impeller 4 may be of any suitable type Well known in the art, the one selected for illustration herein being of integral construction and comprising spaced, opposed discs interconnected by convolute Webs or vanes I (Fig. 2) which deiine similarly shaped passages I5 A hub portion I6 projecting from the inner face of the impeller is provided with a threaded bore for the reception of the threaded end of shaft 3, and centrally at the opposite or outer face of the impeller there is formed a short tubular extension I'l which provides an intake passage for the impeller body.

that converge toward center of the impeller body. 55

Complementing the outer Vend portion of bracket 6 in the formation ofthe impeller housing is a dished end plate I8 having a marginal flange I9 which fits the rabbetted margin of the bracket end wall 5. These housing parts are detachably clamped together in liquid sealing relation by bolts, (not shown) that extend through mating ears formed thereon and indicated at 20.

Formed in the end plate I8, in the plane of and surrounding the peripheral discharge openings of the impeller passages I5 is a circular channel 2|' which conducts the high pressure fluid received from the impeller to the pump discharge passage 22. Such discharge passage is produced by a radial extension .23, formed integrally with the housing member I8 which projects substantially vertically from the top thereof. The lower or intake end 24 of such passage is curved laterally in a suitable manner to merge smoothly with the annular channel 2|, whereby to direct the fluid therefrom without creating undue turbulence.

The radial extension 23 continues forwardly vbeyond the outer end face of housing member i8 where it is provided with a radial injector passage 25 arranged parallel to discharge passage 22 and separated therefrom for a portion of its length by a partitioning web 26. At its upper end discharge passage 22 curves forwardly to communicate with a chamber 21 in passage 25 through a lateral opening therein, and the lower end 28 of the injector passage 25 is rearwardly curved and terminates at an opening 29 which confronts the intake opening provided by the tubular extension Il of the impeller.

Disposed within passage 25 are injector means, comprising a nozzle element 30 and an inductor tube 3l. Nozzle element 30 is located in Passage 25, with its upper or intake end disposed immediately below and in communication with the chamber 21, and is preferably held in place as by press fitting. As best appears from Fig. 1, nozzle 35 extends through a combining chamber 32 in passage 25, and is adapted to form and direct a stream of high velocity fluid into the subtending mouth of inductor tube 3|. Tube 3i ex-l tends downwardly from chamber 32 for substantially the length of passage 25 therebelow, and

is shaped internally to produce the well known Venturi effect. Like nozzle element 30, tube 3| may be secured in place as by a press t connection with the wall surfaces of passage 25 and both of these members are adapted to be installed and withdrawn through an internally threaded nipple 33 forming a vertical continuation of passage 28 above the chamber 21, and defining the discharge terminal ofthe pump. A fragmentary portion 34 of a discharge pipe is shown connected to nipple 33.

A lateral opening 35 in the induction or combining chamber 32 provides the intake or suction port leading into the pump, and an integrally formed, horizontally projecting nipple 36 communicating with .the opening 35 provides a connection for an intake pipe, a portion of which is indicated at 31.

Describing now the operation of the pump assembly, as will be understood, rotation of the impeller 4 causes fluid in the impeller casing to be forced outwardly thereof and through discharge passage 22 into chamber 21. At chamber 21 the high pressure fluid is divided to form two oppositely directed streams, one of such streams discharging upwardly and outwardly of the pump unit through pipe 34, and the other stream flowing downwardlywith increased velocity through nozzle 30 and into the mouth of Venturi tube 3l, for subsequent re-entrance into the suction throat of the impeller housing. The suction normally produced at the intake of the centrifugal pump is augmented by the action of the injector means which, accordingly, increases the lifting capacity of the unit. The discharge chamber 21 is desirably provided with oppositely disposed lateral openings 38 normally closed by plugs 39, either of which may be replaced by a faucet for withdrawing fluid at the unit, such openings also serving to admit priming uid when such becomes necessary. It will appear that since the passages 22 and 25 extend above the pumping chamber they act as stand pipes when the pump is idle and the pumping chamber will normally remain filled.

Having described my invention, what I claim and desire to secure by Letters Patent is:

In a centrifugal pump, the combination of an impeller mounted to rotate about a horizontal axis, a transversely split impeller casing, one secthereof and terminating downwardly at the casing discharge port', said conduits being disposed in parallel, side-by-side relation, and combining to provide a recirculatng passage for pumped fluid, a lateral opening in said rst conduit located immediately below the junction of said conduits and above the impeller casing and providing a pump intake terminal, and injection means in said first conduit, including a nozzle element disposed immedately below the junction of said conduits and directed toward the casing intake, and an inductor tube whose mouth is disposed immediately below the lateral intake terminal in said rst conduit, said first conduit and discharge opening being so constructed and arranged as to enable the nozzle element and Vinductor tube to be inserted and removed therethrough.

LAWRENCE EUGENE DA COL.

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