US3659955A - Device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof - Google Patents

Device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof Download PDF

Info

Publication number
US3659955A
US3659955A US841299A US3659955DA US3659955A US 3659955 A US3659955 A US 3659955A US 841299 A US841299 A US 841299A US 3659955D A US3659955D A US 3659955DA US 3659955 A US3659955 A US 3659955A
Authority
US
United States
Prior art keywords
pump
bore
rotor
liquid
running condition
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US841299A
Other languages
English (en)
Inventor
Siegfried Schonwald
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Siemens Corp
Original Assignee
Siemens Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from DE6600523U external-priority patent/DE6600523U/de
Priority claimed from DE19681703815 external-priority patent/DE1703815C/de
Application filed by Siemens Corp filed Critical Siemens Corp
Application granted granted Critical
Publication of US3659955A publication Critical patent/US3659955A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/44—Fluid-guiding means, e.g. diffusers
    • F04D29/46—Fluid-guiding means, e.g. diffusers adjustable
    • F04D29/48—Fluid-guiding means, e.g. diffusers adjustable for unidirectional fluid flow in reversible pumps
    • F04D29/486—Fluid-guiding means, e.g. diffusers adjustable for unidirectional fluid flow in reversible pumps especially adapted for liquid pumps
    • A—HUMAN NECESSITIES
    • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
    • A47L15/00—Washing or rinsing machines for crockery or tableware
    • A47L15/42—Details
    • A47L15/4214—Water supply, recirculation or discharge arrangements; Devices therefor
    • A47L15/4225—Arrangements or adaption of recirculation or discharge pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0027—Varying behaviour or the very pump
    • F04D15/0044—Varying behaviour or the very pump by introducing a gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0077—Safety measures

Definitions

  • ABSTRACT Device for automatically stopping delivery of liquid by a centrifugal pump operating in reverse running condition through the introduction of air into the pump chamber of the pump includes means defining a bore formed in the housing of the pump for connecting the pump chamber to atmosphere, and means cooperating with the bore-defining means for adjusting the pressure in the pump chamber to positive pressure in forward running condition of the pump rotor and to negative pressure in reverse running condition thereof whereby in the latter condition air is sucked from the atmosphere into the pump chamber to stop delivery of liquid by the pump.
  • a centrifugal pump of radial construction delivers liquid, during reverse rotation of the pump rotor, in the same flowthrough direction as during nonnal or forward rotation of the pump rotor, although with markedly reduced pumping power.
  • This delivery of liquid during reverse operation of the pump must be stopped if, for example, a second pump assembly operates from the same drive shaft as the first-mentioned pump and is dependent on rotary direction, as is, for example, the case with circulating and draining or discharge pumps of dishwashing machines, A further requirement is that the delivery of liquid should stop from the very instant that the pump is switched from forward to reverse operation so that as little liquid as possible leaves the pump at the pressure side thereof.
  • lt is accordingly an object of my invention to provide device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation of the latter which avoids the disadvantages of the heretofore known devices for effecting this purpose. More specifically, objects of my invention are to provide such device which will not disturb liquid flow during forward rotation of the pump rotor, which will not present any danger of obstruction, and which will moreover be relatively inexpensive.
  • I provide, according to my invention, device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof by introducing air into the pump chamber of the pump, comprising means defining a bore formed in the housing of the pump for connecting the pump chamber of the pump to atmosphere, and means cooperating with the boredefining means for adjusting the pressure in the pump chamber to positive pressure in forward running condition of the pump rotor and to negative pressure in reverse running condition thereof, whereby in the latter condition air is sucked from the atmosphere into the pump chamber to stop delivery of liquid.
  • the bore is formed in a surface of the pump housing that is sub jected to flow dependent upon rotational direction, and a bulge is provided upstream of the bore in the reverse rotating direction of the pump rotor.
  • the liquid flow adjacent the surface of the pump housing is blocked by and accumulates at the bulge so that a positive pressure is produced at the bore opening in the pump chamber.
  • the liquid flow adjacent the surface of the pump housing is accelerated as it flows over the bulge so that a negative pressure is produced at the bore opening in the pump chamber.
  • the bulge extends partly around the bore.
  • the flow device comprising the bulge and the bore-defining means are recessed in the housing wall.
  • two pockets are machined or otherwise formed in the housing wall, a bulge being left between the pockets.
  • the bore is located at an end of one of the pockets adjacent the flow-engaging surface of the bulge, which has a steep construction,
  • the surface of the bulge facing away from the bore slopes upwardly from the other pocket.
  • the side surfaces of the pockets in accordance with another feature of the invention, have an upwardly opening funnel shape so as to be able to capture as much liquid as possible.
  • the bore-defining means extend transversely to the rotational plane of the pump rotor and are located within the confines of an angle located between the minimum of the local meridian velocity as the leading limiting edge thereof in the rotational sense of the rotor in the reverse running condition thereof and the maximum of the local meridian velocity as the trailing limiting edge thereof.
  • the bore is located in a region of the space occupied by the rotor wherein, in the reverse running condition of the centrifugal pump, the lowest pressure from the inner to the outer diameter of the rotor occurs.
  • This region is characterized by a minimum of the local meridian velocity as a forward or leading limit in the rotational direction of the rotor in the reverse running condition thereof and a maximum of the local meridian velocity as a rear or trailing limit.
  • This region corresponds substantially to the confines of the angle respectively 15 forward of to 35 behind the tongue point or the narrowest cross section between the housing wall and the rotor or the location of the smallest angle between the housing wall and the radius vector to the housing wall.
  • a centrifugal pump of radial construction with a rotor and spiral housing is conventionallydesigned so that above the rotor space, relative to the rotor, a symmetrical source or intake flow of liquid occurs i.e., the flow velocities or accelerations in concentric or coaxial circles in the rotor space are constant.
  • the flow pattern over the rotor assumes a completely different, nonsymmetrical shape due to superimposition of two flow fields.
  • a source or intake flow symmetrical to the rotor yet having a reduced source magnitude. This flow is superimposed by a second velocity field oscillating relative to the rotor due to the guidance of liquid in the spiral housing.
  • the pressure reduction adjusted between the minimum and the maximum of the meridian velocity for reverse rotational direction of the rotor can be increased if the intermediate region is shortened in the rotational direction, and a greater radial acceleration is thereby produced.
  • the narrowing spiral is sharply inwardly bent at the tongue.
  • the minimum of the meridian velocity is thereby lowered more deeply and is displaced toward the pressure tube extension.
  • the bore in the pump housing is additionally surrounded by flow guides open to the main liquid flow, in accordance with another feature of my invention.
  • the bore in the housing wall is provided with the aforementioned bulge at one side thereof which, in another embodiment of the invention, partly surrounds the bore so as to increase the blocking of the liquid and thereby the positive pressure at the bore in the forward running condition of the pump.
  • the aforedescribed flow device including the bore-defining means for admitting air to the pump chamber is not limited only to the aforedescribed region of alternating pressure but rather can actually be applied to all surfaces of the pump housing subjected to flow dependent upon rotational direction. Especially advantageous is, of course, the effect at a location at which the pressure, in the reverse running condition of the pump, is in any case already lower than in the forward running condition of the pump. Such a region is found, as aforementioned, transversely to the plane of rotation of the rotor in vicinity of the pressure tube extension at the spiral.
  • FIG. 1 is a partly diagrammatic plan view of the pump of my invention with the housing cover thereof removed;
  • FIG. 2 is a plan view of the housing cover removed from the housing of FIG. 1;
  • FIGS. 3a and 3b are a top plan view and a longitudinal sectional view, respectively, of one embodiment of the flow guiding device of my invention wherein the bulge and bore thereof are recessed in the housing wall of the pump;
  • FIGS. 4a and 4b are a top plan view and a longitudinal sectional view, respectively of another embodiment of FIGS. 3a and 3b wherein the bulge projects from the housing wall of the pump.
  • FIGS. 1 and 2 there is shown a centrifugal pump having a rotor l which, in forward rotating condition thereof, rotates in the direction of the arrow 20, and liquid, such as water, is flung centrifugally outwardly from the suction opening 3 into the channel 4 widening outwardly spirally between the rotor l and the housing wall 13, and is discharged from the pump through the pressure tubes 5.
  • liquid such as water
  • a bore 7 is formed in the pump housing cover 6, and can be connected by a tube to the inner chamber of a dishwashing machine, for example.
  • the optimum location of the bore is dependent in a known manner upon the construction of the pump. lts exact position is variable for example, in accordance with the amount of bend in the point of the tongue 8 forming part of the pump housing.
  • FIG. 1 there is shown in single-line hatching a region 9 of the pump substantially wherein a bore will produce the desired effect for a centrifugal pump of the illustrated type.
  • This region 9 is radially inwardly limited by the fact that negative pressure prevails at this inner limit both in the forward as well as the reverse operating conditions of the rotor 1, while the region 9 is limited radially outwardly by the fact that no adequate pressure reduction is realized any longer at this outer limit in the reverse operating condition of the rotor.
  • the bore 7, in the structure of the embodiment shown in FIG. 1, is located on a radius angularly displaced 25 from the reference radius in the reverse running direction of the rotor l, and actually still within the confines of the space occupied by the rotor 1.
  • FIGS. 3a and 3b there is shown one embodiment of the flow guide according to my invention wherein two pockets [0 and 11 are machined or otherwise formed in the inner surface of the cover 6 of the pump housing, a bulge 12 being left between the two pockets.
  • a bore 7 is located at one end of the pocket 11 adjacent the flow-engaging surface of the bulge 12, which has a steep construction.
  • the surface of the bulge 12 facing away from the bore 7 extends upwardly at an inclination from the other pocket 10.
  • the side surfaces of the pockets 10 and 11 are funnel-shaped and open upwardly as viewed in FIG. 3b so as to capture as much of the liquid in the pump, as possible.
  • both the bulge l2 and the bore 12 are thus recessed in the housing cover 6.
  • the aforedescribed flow device can be dispensed with, in fact when the bore is formed in a recess which has inclined side surfaces in the reverse running direction of the rotor.
  • the bore and the non-illustrated tube connected thereto are thereby prevented from filiing with spray water in the reverse running condition of the pump.
  • a bulge 22 which partly surrounds the bore 7.
  • the liquid flow adjacent the surface of the housing wall and cover accumulates at the bulge 22 so that a positive pressure is produced at the bore 7. Consequently, in the forward running direction of the rotor, only water is delivered but no air is aspirated into the pump.
  • the regions at which the bore may be located approximately coincide.
  • Device for automatically stopping delivery of liquid by a centrifugal pump having a spiral housing provided with a transverse side wall and a rotor with an open blading rotatably mounted therein and operating in reverse running condition through the introduction of air into the pump chamber of the pump comprising a tongue formed on the spiral housing and projecting adjacent the periphery of the rotor, means defining a bore formed in the side wall of the housing of the pump for connecting the pump to atmosphere, said means having an abrupt projecting surface engageable by the liquid in forward running condition of the pump and a smooth inclined surface, located opposite said abrupt projecting surface, and engageable by the liquid in reverse running condition of the pump, said bore extending transversely to the rotational plane of the pump rotor and communicating with the open blading of said pump rotor, said bore being located within the peripheral area covered by the rotor blading and said location being within the confines of an angle forward of to 35 behind said tongue in the forward running condition of the pump.
  • Device including means cooperating with said bore-defining means for adjusting the pressure in the pump chamber to positive pressure in forward running condition of the pump rotor and to negative pressure in reverse running condition thereof whereby in the latter condition air is sucked from the atmosphere into the pump chamber to stop delivery of liquid by the pump.
  • said pressure adjusting means comprises a bulge located in fluid flow stream of the pump upstream of said bore in the reverse running condition of the pump.
  • the spiral pump housing is formed with a tongue disposed adjacent the periphery of the pump rotor, said bore being located on a radius of the rotor displaced substantially through an angle of 25 from a radius of the rotor passing through the tip of said tongue as viewed in reverse running direction of the rotor.
  • the spiral housing has a construction wherein an angle a between a tangent to the spiral of the housing and a radius r located at the vicinity of said tongue is smaller than at the remaining periphery of said spiral.
  • said bulge being i t i k lOlDJl 056i

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
US841299A 1968-07-13 1969-07-14 Device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof Expired - Lifetime US3659955A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE6600523U DE6600523U (de) 1968-07-13 1968-07-13 Selbsttaetige unterbindung der fluessigkeitsfoerderung einer kreiselpumpe bei rueckwaertslauf
DE19681703815 DE1703815C (de) 1968-07-13 Einrichtung zum selbsttätigen Unterbinden der Flüssigkeitsförderung einer radialen Kreiselpumpe bei Rückwärtslauf

Publications (1)

Publication Number Publication Date
US3659955A true US3659955A (en) 1972-05-02

Family

ID=25754678

Family Applications (1)

Application Number Title Priority Date Filing Date
US841299A Expired - Lifetime US3659955A (en) 1968-07-13 1969-07-14 Device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof

Country Status (6)

Country Link
US (1) US3659955A (de)
CH (2) CH503907A (de)
FR (1) FR2014590A1 (de)
GB (2) GB1217460A (de)
NL (1) NL6909152A (de)
SE (1) SE354689B (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120148393A1 (en) * 2010-12-14 2012-06-14 Delta Electronics, Inc. Centrifugal fan
CN103267018A (zh) * 2013-06-03 2013-08-28 高邮市高农机械配件有限公司 内燃机冷却水泵吸水室流道

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3929758C2 (de) * 1989-09-07 1994-11-17 Klein Schanzlin & Becker Ag Kreiselpumpengehäuse in Blechbauweise

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1783667A (en) * 1930-01-28 1930-12-02 Deming Co Centrifugal pump
US2050523A (en) * 1935-07-08 1936-08-11 Edward A Freed Fan
FR861453A (fr) * 1938-11-18 1941-02-10 Masch Fabrikburckhardt A G Pompe rotative à roue à ailettes, à anneau de liquide, pourle déplacement simultané d'un gaz et d'un liquide
US2291138A (en) * 1939-01-05 1942-07-28 Bingham Pump Company Inc Centrifugal pump
US2566892A (en) * 1949-09-17 1951-09-04 Gen Electric Turbine type pump for hydraulic governing systems
US2808780A (en) * 1952-10-07 1957-10-08 Philips Corp Rotary pump
US3040663A (en) * 1959-12-30 1962-06-26 Gen Electric Two-way valveless pump
US3134386A (en) * 1963-01-24 1964-05-26 Gen Electric Washing machine with selectively variable washing action
US3227089A (en) * 1963-04-23 1966-01-04 Philips Corp Centrifugal pump
US3244105A (en) * 1963-03-26 1966-04-05 Gen Motors Corp Pump for a domestic appliance
US3259072A (en) * 1964-10-26 1966-07-05 Gen Motors Corp Rotary fuel pump

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1783667A (en) * 1930-01-28 1930-12-02 Deming Co Centrifugal pump
US2050523A (en) * 1935-07-08 1936-08-11 Edward A Freed Fan
FR861453A (fr) * 1938-11-18 1941-02-10 Masch Fabrikburckhardt A G Pompe rotative à roue à ailettes, à anneau de liquide, pourle déplacement simultané d'un gaz et d'un liquide
US2291138A (en) * 1939-01-05 1942-07-28 Bingham Pump Company Inc Centrifugal pump
US2566892A (en) * 1949-09-17 1951-09-04 Gen Electric Turbine type pump for hydraulic governing systems
US2808780A (en) * 1952-10-07 1957-10-08 Philips Corp Rotary pump
US3040663A (en) * 1959-12-30 1962-06-26 Gen Electric Two-way valveless pump
US3134386A (en) * 1963-01-24 1964-05-26 Gen Electric Washing machine with selectively variable washing action
US3244105A (en) * 1963-03-26 1966-04-05 Gen Motors Corp Pump for a domestic appliance
US3227089A (en) * 1963-04-23 1966-01-04 Philips Corp Centrifugal pump
US3259072A (en) * 1964-10-26 1966-07-05 Gen Motors Corp Rotary fuel pump

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120148393A1 (en) * 2010-12-14 2012-06-14 Delta Electronics, Inc. Centrifugal fan
US8967962B2 (en) * 2010-12-14 2015-03-03 Delta Electronics, Inc. Centrifugal fan
US9964119B2 (en) 2010-12-14 2018-05-08 Delta Electronics, Inc. Centrifugal fan
CN103267018A (zh) * 2013-06-03 2013-08-28 高邮市高农机械配件有限公司 内燃机冷却水泵吸水室流道

Also Published As

Publication number Publication date
CH492880A (de) 1970-06-30
DE1703815B2 (de) 1972-09-21
CH503907A (de) 1971-02-28
NL6909152A (de) 1970-01-15
DE1703815A1 (de) 1972-03-09
FR2014590A1 (de) 1970-04-17
SE354689B (de) 1973-03-19
GB1217460A (en) 1970-12-31
GB1213448A (en) 1970-11-25

Similar Documents

Publication Publication Date Title
US6582189B2 (en) Turbo machines
US5167678A (en) Apparatus for separating gas with a pump from a medium being pumped
US4642023A (en) Vented shrouded inducer
US5551842A (en) Unit for delivering fuel from a supply tank to the internal combustion engine of a motor vehicle
US3542496A (en) Dishwasher pump
JPS6114500A (ja) 渦防止インデューサ組立体及びポンプ
US3659955A (en) Device for automatically stopping delivery of liquid by a centrifugal pump during reverse operation thereof
JPS62261699A (ja) 流体圧機械特に遠心ポンプ
US3085741A (en) Centrifugal fans
US2623466A (en) Dual discharge pump
KR100299266B1 (ko) 재생펌프
US2918017A (en) Centrifugal pumps
US2933045A (en) Centrifugal pumps
US2580347A (en) Centrifugal pump
US2405836A (en) Self-priming pump
CN115151729A (zh) 排水泵
WO2017154151A1 (ja) 電動送風機および電気掃除機
KR102518288B1 (ko) 일체형 가스 및 오일 씰링 구조를 포함하는 압축기
US3073527A (en) Dishwashing machines
US5779433A (en) Rotary suction and blowing machine
USRE25409E (en) Coester
JP2579695B2 (ja) 段付き軸流インデューサ
US2184349A (en) Pump
JP3771794B2 (ja) 遠心ポンプ
US3506374A (en) Self-priming pump