US2376071A - Centrifugal pump - Google Patents

Centrifugal pump Download PDF

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Publication number
US2376071A
US2376071A US354432A US35443240A US2376071A US 2376071 A US2376071 A US 2376071A US 354432 A US354432 A US 354432A US 35443240 A US35443240 A US 35443240A US 2376071 A US2376071 A US 2376071A
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casing
liquid
stationary
tubular
hood
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US354432A
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Miess Fred
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Priority to US538906A priority patent/US2419905A/en
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D1/00Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
    • F04D1/12Pumps with scoops or like paring members protruding in the fluid circulating in a bowl
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D1/00Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
    • F04D1/14Pumps raising fluids by centrifugal force within a conical rotary bowl with vertical axis

Definitions

  • Centrifugal pumps of conventional design com prise a stationary casing, arotary impeller within the casing, a. shaft for supporting and motlvating the impeller; packing glands around the shaft where it-passes through the casing, and bearing means for supporting the shaft for-rotation.
  • centrifugal "pumps are subject to rapid wear and consequent loss of efllciency when handling gritty or other destructive liquids, and this isparticularly true of the rotary impeller and the packing glands;
  • Another difficultywith such dlately beneath the lower portion of the casing 5 is a'sump I2 which is'adapted to receive the liquid to be pumped. Beneath, andclosely adjacent,
  • centrifugal pump which overcomes the shortcomings of prior art devices in that iteliminates the necessity of packing glands; is self-priming, and requires no foot valve.
  • centrifugal pump which is of extremely simple and inexpensive design, consisting fundamentally of a rotating element which serves as both the casing and the rotary impeller.
  • Figure 2 is a vertical elevation showing part of the pump in section
  • Figure 4 is a but showing a mo view on the line Ill-Ill view similar tothat of Figure 1- cation;
  • Figure 6 is a-view similar tothat ofFlgures .2 and 5 but disclosing still another modification.
  • FIG. 5 is a'vertical; sectional elevation-of the Referring more particularly to the drawings,
  • lthe numerals I and 2 designate a pair of spaced bearingathe shaft-receiying apertures 01 which are in vertical alignment and are adapted 'to.receive a shaft 3' which depends therefrom and has integrally formed at the lower end thereof a right 'an'gular flange I from which there depends a tubular housing 5 which takes the shape of an "inverted frusto-cone. Immediately below the v flange 4, the upper, and therefore largest. portion 55 face of the-casing is preferably provided'with :I''
  • annular trough I4 This annular trough llprovides an outer wall which extends upwardly beyond the horizontal plane of-the upper surface of the annular flange! and a concentric inner wall which is closely adjacent the outer surface of the upper portion of the flange 5 and terminates imme-' diately below the tubular extensions 6.
  • the lower portion of the outer wall of the annular trough ll isprovided with an aperture I! with which there is connected a spout I8.
  • This spout I8 is connected :(not shown) with the inst'rumentality to'which the liquid is'to be pumped; and'a .re--
  • turn pipe (likewise not shown), is connected to the sump l2, thus-providing a circuit.
  • the shape of the said casing is to a large extent immaterial so faras i ability to function is concerned.
  • the inverted frusto-cone is preferable from the standpoint of emciency, and-principally to enable the entering liquid to more readily attainthe rotary motion of the casing,
  • Figures 4 and 5 wherein there is illustrated a form which is in most respects similar to the embodiment of Figures 1 and 2, except that there is provided what is equivalent to the sealing of the annular trough l4.
  • the numeral 25 designates a pulley which is mounted on a suitably supported bearing 26 for rotation on a vertical axis. Integrally connected to the bottom of the pulley 25 at a position slightly below the bearing 26 is an annular flange 28which is suitably connected to a spaced parallel annular flange 30 as by means of the ears and nuts and bolts collectively designated at 32.
  • the mid-portion of the flange 30 is downwardly diverted into an inverted frusto-conical casing 535, the axis of which is coincident with the axis of the pulley 25.
  • the casing 35 extends downwardly into a sump l2 and carries on its inner surface a pair of opposed helical vanes 13B.
  • the casing 35 forces the liquid to rise from the sump E2, move through the interior thereof in the direction of the arrows of Figures 5, through the apertures 2-3 in the tubular extensions 41 carried by the flanges M and d5, inwardly to the bottom of the hollow tube 58 and upwardly therethrough. It is evident that the liquid in the space around the stationary apertures 47 is under pressure from centrifugal force, since the liquid is rotating with the casing 35. Since there is no centrifugal pressure in the stationary tube 50 or the stationary tubular extensions d! carried by the spaced annular flanges M and 45, it is further evident that the liquid under pressure in the casing 35 will discharge through the openings 48 in the stationary tubular extensions 417 and the stationary tube 58.
  • a centrifugal pump adapted to lift liquid from a sump containing the liquid to be pumped, the said pump comprising a substantially vertically disposed rotatable tubular casing having its upper end abruptly expanded into an enlarged head defining an annular liquid-receiving compartment, stationary means in the head in concentric relation thereto for receivin liquid from the liquid-receiving compartment, the said concentric stationary means having oppositely directed tubular extensions communicating with oppositely disposed liquid passage ports through the concentric means, the said ports extending According to the construction and arthe device which is disposed above the casing 35.
  • the function of the jacket 55 is to permit depression of the liquid level inside the jacket below the liquid level outside of the said jacket by means of gas undersuitable pressure, thereby eliminating the friction which would exist between the casing 35 and the surrounding liquid, if it were through the said extensions and having liquid intake openings in end portions of the extensions while being disposed in a horizontal plane, the said intake openings of-the ports projecting in a direction tangential to the rotation of the rotatable casing and in opposition to the direction of rotation of the rotatable casing, the intake openings of the ports being spaced at a greater distance from the axis of rotation of the tubular casing than the peripheral wall of the lower end of the tubular casing, stationary vertical discharge means for conducting liquid under pressure vertically upwardly from the said concentric stationary means, mechanism for rotating the casing, the said tubular casing having an open lower end forming a liquid intake opening, a gastight hood en
  • a centrifugal pump adapted to lift liquid from a sump containing the liquid to be pumped
  • the said pump comprising a substantially vercentric stationary means having oppositely directed tubular extensions communicating with oppositely disposed liquid passage ports through the saidconcentric stationary means, the said ports extending through the said extensions and ihavin in ake openin s in end portions thereof while being disposed in a horizontal plane, the
  • said depending portion of the hood being of inverted frusto-conical shape substantially concentric with the rotating casing of the pump and containing a gas under sumcient pressure to depress the liquid within the housing to a level below that of the liquid outside of the housing,

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Description

May 15,1945. F. M|Ess 2,376,071
CENTRIFUGAL PUMP Filed Aug. 27, 1940 2 Sheets-Sheet 1 liweizlar: flea-0 -M/55.
ay '15, 1945. F, MESS 2,376,071-
CENTRIFUGAL PUMP 2 Sheets- Sheet 2 Filed Au 27, 1940 F-IE ' .J/ 5.5 H 1E i i' mm HT j 2! 44 .5? Q v 7 i B m If! I fawenlor: 7 2250 M555,
Patented May 15,1945- 2 Claims. (onion-101) of the casing 5 is provided 7 V opposite-tubular-extensions i, the side faces of invention relates to centrifugal pumps and more particularly to one which may be used for handling and distributing mercury in an electrical ignition apparatus, although not limited thereto.
' Centrifugal pumps of conventional design com prise a stationary casing, arotary impeller within the casing, a. shaft for supporting and motlvating the impeller; packing glands around the shaft where it-passes through the casing, and bearing means for supporting the shaft for-rotation.
- tures 1, whereby the said apertures may face a' tween the bearings i and 2 the shaftcured thereto ap'ulley 8 to which there nected a belt 9, thelatter deriving energy froin' which are provided with reverselyw disposed" apergiven direction of rotation of the ca'sin 5. Be-
- any suitable source (not shown). Disposed imme- Such centrifugal "pumps are subject to rapid wear and consequent loss of efllciency when handling gritty or other destructive liquids, and this isparticularly true of the rotary impeller and the packing glands; Another difficultywith such dlately beneath the lower portion of the casing 5 is a'sump I2 which is'adapted to receive the liquid to be pumped. Beneath, andclosely adjacent,
- the upper portion of the casing 5, and accordingly the flange l which is integrally formed onrthe pumps is that unless they are submerged, prim- 'ing is required, and this is easily lost by a slight i leakage in the packing glands or "foot? valvesof the pumps.
It is among the objects of the present invention to provide a centrifugal pump which overcomes the shortcomings of prior art devices in that iteliminates the necessity of packing glands; is self-priming, and requires no foot valve.
Another object is the provision of a centrifugal pump which is of extremely simple and inexpensive design, consisting fundamentally of a rotating element which serves as both the casing and the rotary impeller.
The foregoing and other objects become apparent after referring to the drawings.
In said drawings: I V a Figure 1 is a plan of the top'of the pump of the present invention; v
Figure 2 is a vertical elevation showing part of the pump in section;
Figure 31s a sectional of Figure 2;
Figure 4 is a but showing a mo view on the line Ill-Ill view similar tothat of Figure 1- cation;
'modifled form of Figure}; and
Figure 6 is a-view similar tothat ofFlgures .2 and 5 but disclosing still another modification."
Figure 5 is a'vertical; sectional elevation-of the Referring more particularly to the drawings,
lthe numerals I and 2 designate a pair of spaced bearingathe shaft-receiying apertures 01 which are in vertical alignment and are adapted 'to.receive a shaft 3' which depends therefrom and has integrally formed at the lower end thereof a right 'an'gular flange I from which there depends a tubular housing 5 which takes the shape of an "inverted frusto-cone. Immediately below the v flange 4, the upper, and therefore largest. portion 55 face of the-casing is preferably provided'with :I''
bottom of the shaft 3, is .a stationary annular trough I4, This annular trough llprovides an outer wall which extends upwardly beyond the horizontal plane of-the upper surface of the annular flange! and a concentric inner wall which is closely adjacent the outer surface of the upper portion of the flange 5 and terminates imme-' diately below the tubular extensions 6. The lower portion of the outer wall of the annular trough ll isprovided with an aperture I! with which there is connected a spout I8. This spout I8 is connected :(not shown) with the inst'rumentality to'which the liquid is'to be pumped; and'a .re--
turn pipe (likewise not shown), is connected to the sump l2, thus-providing a circuit.
Y According to the .manner of operation of the device of the present-invention; it be found that when the sump I2 is continuously provided; Y with sufllicent liquid to rise upwardly into .the
lower portion of the casing 5. rotation-of the latter at 'suilicient speed will cause the liquid to acquire the motion ofthe rotating casing and tend to cause it to rise along the sidewalls thereof. Centrifugal force will cause it to flow 'outwardlyfthrough the apertures 1 .in the tubular extensions 8 in the direction of the arrows of Figures l and}: The liquid is made to .flow in the manner described 'as long as liquid continues to enter the bottom of the casing 5 from..the f sump l2." One essential is that the liquid must enter the casing 5 nearer its axis of-fr'otation than the poiiitatwhichit leaves the upper po tion of'the' said casing. The shape of the said casing is to a large extent immaterial so faras i ability to function is concerned. However, the inverted frusto-cone is preferable from the standpoint of emciency, and-principally to enable the entering liquid to more readily attainthe rotary motion of the casing, In addition, the inner sur.--
with a pair of radially has se- 7 opposed helical vanes 20 which enhance the at- I tainment of therotary motion of the liquid.
attention is directed to Figures 4 and 5, wherein there is illustrated a form which is in most respects similar to the embodiment of Figures 1 and 2, except that there is provided what is equivalent to the sealing of the annular trough l4. Herein the numeral 25 designates a pulley which is mounted on a suitably supported bearing 26 for rotation on a vertical axis. Integrally connected to the bottom of the pulley 25 at a position slightly below the bearing 26 is an annular flange 28which is suitably connected to a spaced parallel annular flange 30 as by means of the ears and nuts and bolts collectively designated at 32. The mid-portion of the flange 30 is downwardly diverted into an inverted frusto-conical casing 535, the axis of which is coincident with the axis of the pulley 25. In the manner of the embodiment of Figures 1 and 2, the casing 35 extends downwardly into a sump l2 and carries on its inner surface a pair of opposed helical vanes 13B. rangement of the flanges 28 and 3!] of the embodiment of Figures 4 and 5, there is provided therebetween a hollow basin 42 in which there is disposed in spaced relationship with respect to the inner surfaces of the walls thereof a pair of spaced parallel flanges M and 45 which carry a pair of radially opposite tubular extensions 37 which are provided with reversely disposed apertures 48. Referring again to Figure 5, the midportion of the flange M terminates in a tubular shaft 50 which extends upwardly through the pulley and is secured against rotation therewith by means of a suitable clamping bracket 5|. The operation of the embodiment of Figures 4 and 5 is as follows:
Upon the rotation of the pulley 25, the casing 35 forces the liquid to rise from the sump E2, move through the interior thereof in the direction of the arrows of Figures 5, through the apertures 2-3 in the tubular extensions 41 carried by the flanges M and d5, inwardly to the bottom of the hollow tube 58 and upwardly therethrough. It is evident that the liquid in the space around the stationary apertures 47 is under pressure from centrifugal force, since the liquid is rotating with the casing 35. Since there is no centrifugal pressure in the stationary tube 50 or the stationary tubular extensions d! carried by the spaced annular flanges M and 45, it is further evident that the liquid under pressure in the casing 35 will discharge through the openings 48 in the stationary tubular extensions 417 and the stationary tube 58.
Referring to Figure 6 of the drawings, I have shown a second modification which difiers only from that of Figures 4 and 5 by the addition of a stationary air-tight jacket 55 for that portion of This air-tight jacket 55 carries a lower comnot displaced by the said gas. The pressure of the gas in the jacket 55 is proportional to the difference between the outside and inside liquid levels and therefore can be used to control the starting andstopping of the pump.
While I have shown and described several specific embodiments ofthe present invention, it will be readily understood by those skilled in the art that I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of the invention as defined'by the appended claims.
I claim:
1. A centrifugal pump adapted to lift liquid from a sump containing the liquid to be pumped, the said pump comprising a substantially vertically disposed rotatable tubular casing having its upper end abruptly expanded into an enlarged head defining an annular liquid-receiving compartment, stationary means in the head in concentric relation thereto for receivin liquid from the liquid-receiving compartment, the said concentric stationary means having oppositely directed tubular extensions communicating with oppositely disposed liquid passage ports through the concentric means, the said ports extending According to the construction and arthe device which is disposed above the casing 35.
municating inverted frusto-conical extension 58 whichis concentric with the rotary casing 35. The function of the jacket 55 is to permit depression of the liquid level inside the jacket below the liquid level outside of the said jacket by means of gas undersuitable pressure, thereby eliminating the friction which would exist between the casing 35 and the surrounding liquid, if it were through the said extensions and having liquid intake openings in end portions of the extensions while being disposed in a horizontal plane, the said intake openings of-the ports projecting in a direction tangential to the rotation of the rotatable casing and in opposition to the direction of rotation of the rotatable casing, the intake openings of the ports being spaced at a greater distance from the axis of rotation of the tubular casing than the peripheral wall of the lower end of the tubular casing, stationary vertical discharge means for conducting liquid under pressure vertically upwardly from the said concentric stationary means, mechanism for rotating the casing, the said tubular casing having an open lower end forming a liquid intake opening, a gastight hood enclosing the said enlarged head and mechanism for rotating the casing, the said hood having aidepending portion enclosing the rotating casing and forming a housing therefor, the depending portion of the hood being adapted to extending into the liquid being pumped, the said liquid thereby forming a seal for the hood, and an upstanding portion of the hood forming a sleeve for the stationary vertical discharge means in gas-tight relation therewith.
2. A centrifugal pump adapted to lift liquid from a sump containing the liquid to be pumped,
the said pump comprising a substantially vercentric stationary means having oppositely directed tubular extensions communicating with oppositely disposed liquid passage ports through the saidconcentric stationary means, the said ports extending through the said extensions and ihavin in ake openin s in end portions thereof while being disposed in a horizontal plane, the
said intake openings of the ports projecting in a direction of rotation tangential to the rotation of the rotatable casing and in opposition to the direction of rotation of the casing, the said intake openings of the port being spaced at a greater distance from the axis ofrotation of the tubular casing than the peripheral wall ofthe lower end of the tubular casing, stationary vertical discharge means for conducting liquid under pressure vertically upwardly from the said concentric stationary means; mechanism for rotating the casing, the said tubular casing having an open lower end forming a liquid intake opening, a gastight hood enclosing the enlarged'head and mech anism' for rotating the casing, the said hood having 2. depending portion enclosing the rotating casing and forming a housing therefor, the depending portion of the hood being adapted to extend into the liquid being pumped, the said liquid thereby forming a seal for the hood, the
said depending portion of the hood being of inverted frusto-conical shape substantially concentric with the rotating casing of the pump and containing a gas under sumcient pressure to depress the liquid within the housing to a level below that of the liquid outside of the housing,
thereby reducing iriction between the pump casing and surrounding liquid, the pressure of the said gas controlling starting and stopping of the pump, and an upstanding portion of the hood forming a sleeve for the stationary vertical discharge means in gas-tight relation therewith.
mums.
US354432A 1940-08-27 1940-08-27 Centrifugal pump Expired - Lifetime US2376071A (en)

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2436034A (en) * 1942-11-13 1948-02-17 Economy Pumps Inc Pump with rotary casing
US2630069A (en) * 1946-05-20 1953-03-03 Thaddeus S Harris Automatic control unit for deep well jet pumps
US2882698A (en) * 1955-01-31 1959-04-21 John R Boyle Refrigerating system
US3091183A (en) * 1960-02-23 1963-05-28 James R Nahrgang Centrifugal pump
US3519365A (en) * 1968-09-30 1970-07-07 Alfred Conhagen Centrifugal pump
US3791757A (en) * 1970-09-11 1974-02-12 Sener Tecnica Industrial New type of rotary pump for liquids
US3936214A (en) * 1975-01-22 1976-02-03 Sun Oil Company Pumping two-phase fluids
JPS54146002A (en) * 1978-05-04 1979-11-14 Fueeresu Fuakurafu Pump for conveying liquid under vacuum
US6698916B2 (en) * 2001-06-19 2004-03-02 Toyo Denki Industrial Co., Ltd. Underwater agitation pump
US20070110560A1 (en) * 2005-11-17 2007-05-17 Clement Roger B Vertically-oriented centrifugal pump
WO2014152448A1 (en) 2013-03-15 2014-09-25 Envirotech Pumpsystems, Inc. Gear-driven flow-through pitot tube pump
US20170191378A1 (en) * 2015-12-30 2017-07-06 General Electric Company Method and system for centrifugal pump

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2436034A (en) * 1942-11-13 1948-02-17 Economy Pumps Inc Pump with rotary casing
US2630069A (en) * 1946-05-20 1953-03-03 Thaddeus S Harris Automatic control unit for deep well jet pumps
US2882698A (en) * 1955-01-31 1959-04-21 John R Boyle Refrigerating system
US3091183A (en) * 1960-02-23 1963-05-28 James R Nahrgang Centrifugal pump
US3519365A (en) * 1968-09-30 1970-07-07 Alfred Conhagen Centrifugal pump
US3791757A (en) * 1970-09-11 1974-02-12 Sener Tecnica Industrial New type of rotary pump for liquids
US3936214A (en) * 1975-01-22 1976-02-03 Sun Oil Company Pumping two-phase fluids
JPS6337280B2 (en) * 1978-05-04 1988-07-25 Fueeresu Fuakurafu
JPS54146002A (en) * 1978-05-04 1979-11-14 Fueeresu Fuakurafu Pump for conveying liquid under vacuum
US6698916B2 (en) * 2001-06-19 2004-03-02 Toyo Denki Industrial Co., Ltd. Underwater agitation pump
US20070110560A1 (en) * 2005-11-17 2007-05-17 Clement Roger B Vertically-oriented centrifugal pump
US7686573B2 (en) * 2005-11-17 2010-03-30 Clement Roger B Vertically-oriented centrifugal pump
WO2014152448A1 (en) 2013-03-15 2014-09-25 Envirotech Pumpsystems, Inc. Gear-driven flow-through pitot tube pump
CN105308325A (en) * 2013-03-15 2016-02-03 环境技术泵系统股份有限公司 Gear-driven flow-through pitot tube pump
EP2971784A4 (en) * 2013-03-15 2016-10-19 Envirotech Pumpsystems Inc Gear-driven flow-through pitot tube pump
US10151314B2 (en) 2013-03-15 2018-12-11 Envirotech Pumpsystems, Inc. Gear-driven flow-through pitot tube pump
US20170191378A1 (en) * 2015-12-30 2017-07-06 General Electric Company Method and system for centrifugal pump
US10060290B2 (en) * 2015-12-30 2018-08-28 General Electric Company Method and system for centrifugal pump

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