EP0171515A1 - Centrifugal pump with an isolating tubular air gap cap - Google Patents

Centrifugal pump with an isolating tubular air gap cap Download PDF

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Publication number
EP0171515A1
EP0171515A1 EP85105626A EP85105626A EP0171515A1 EP 0171515 A1 EP0171515 A1 EP 0171515A1 EP 85105626 A EP85105626 A EP 85105626A EP 85105626 A EP85105626 A EP 85105626A EP 0171515 A1 EP0171515 A1 EP 0171515A1
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EP
European Patent Office
Prior art keywords
pump
pump impeller
impeller
centrifugal pump
pot
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.)
Granted
Application number
EP85105626A
Other languages
German (de)
French (fr)
Other versions
EP0171515B1 (en
Inventor
Ernst Hauenstein
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.)
CP Pumpen AG
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CP Pumpen AG
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Filing date
Publication date
Application filed by CP Pumpen AG filed Critical CP Pumpen AG
Priority to AT85105626T priority Critical patent/ATE29275T1/en
Publication of EP0171515A1 publication Critical patent/EP0171515A1/en
Application granted granted Critical
Publication of EP0171515B1 publication Critical patent/EP0171515B1/en
Expired legal-status Critical Current

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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
    • F04D13/00—Pumping installations or systems
    • F04D13/02—Units comprising pumps and their driving means
    • F04D13/021—Units comprising pumps and their driving means containing a coupling
    • F04D13/024—Units comprising pumps and their driving means containing a coupling a magnetic coupling
    • F04D13/027—Details of the magnetic circuit
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00—Pumping installations or systems
    • F04D13/02—Units comprising pumps and their driving means
    • F04D13/021—Units comprising pumps and their driving means containing a coupling
    • F04D13/024—Units comprising pumps and their driving means containing a coupling a magnetic coupling
    • F04D13/025—Details of the can separating the pump and drive area
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00—Pumping installations or systems
    • F04D13/02—Units comprising pumps and their driving means
    • F04D13/021—Units comprising pumps and their driving means containing a coupling
    • F04D13/024—Units comprising pumps and their driving means containing a coupling a magnetic coupling
    • F04D13/026—Details of the bearings
    • 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
    • F04D29/04—Shafts or bearings, or assemblies thereof
    • F04D29/041—Axial thrust balancing
    • F04D29/0416—Axial thrust balancing balancing pistons
    • 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
    • F04D29/08—Sealings
    • F04D29/16—Sealings between pressure and suction sides
    • F04D29/165—Sealings between pressure and suction sides especially adapted for liquid pumps
    • F04D29/167—Sealings between pressure and suction sides especially adapted for liquid pumps of a centrifugal flow wheel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2260/00—Function
    • F05B2260/40—Transmission of power
    • F05B2260/404—Transmission of power through magnetic drive coupling
    • F05B2260/4041—Transmission of power through magnetic drive coupling the driven magnets encircling the driver magnets

Definitions

  • the invention relates to a centrifugal pump according to the preamble of claim 1.
  • centrifugal pumps are known from DE-OS 26 20 502, the axis being at least partially held on the canned pot bottom, which can result in undesirable mechanical stress on the canned pot and can cause difficulties in equalizing pressure differences behind and in front of the pump impeller.
  • DE-OS 27 33 631 It is provided in DE-OS 27 33 631 to compensate for the fluctuating axial forces by controlling the passage of the compensating opening of the pump impeller, which can at least lead to undesired disturbances in the impeller flow and to loss of performance.
  • EP-A1 0 078 345 in turn, even provides a control device for increasing the cross section of compensation openings in the pump housing, which is from the axial position of the shaft is controlled.
  • CH-PS 529 929 wearable axial main bearings and axial auxiliary bearings are provided, the wear of which allows the axial displacement of the pump impeller under certain operating conditions, which should result in a reduction in axial force.
  • new wear and a new "run-in" is always necessary, which must ultimately lead to total wear of the thrust bearings.
  • the invention is based on the object of avoiding these disadvantages, the short stationary axis already having the advantage in comparison to the long idling shafts that one does not have to take into account the lubrication of a bearing located far away from the motor.
  • the aim was to have a construction that was as simple and economical as possible and easy to maintain.
  • This balancing effect is so excellent that you can do without an axial bearing of the pump impeller if you use both the space behind and in front of the pump impeller with the intake and pressure ports to conduct the medium, e.g. connects in a liquid-conducting manner, the size of the passage cross-sections being variable due to the axial position of the pump impeller and allowing the desired compensation to be achieved automatically.
  • drados rings which are attached to the front and rear of the impeller and are preferably located near the axle on the front. At least on the front, a mating ring on the housing is preferable, while on the back the bottom of the pot can serve as an emergency support.
  • These rings can advantageously have emergency running properties and consist, for example, of polytetrafluoroethylene, which is chemically stable and is well self-lubricating.
  • the throttle rings will hardly ever come into contact in normal operation, since they are separated from each other or from the bottom of the pot by a damping medium layer and, in the event of extreme movements of the pump impeller in one direction, will intercept and immediately regulate the balancing effect.
  • a canned pot 2 is inserted so tightly in the pump housing 1 that the canned pot 2 separates the pump chamber 3 from the motor chamber 4 in a sealed manner and without any movable seals.
  • the pump impeller 5 is housed connected to the associated external rotor 6 equipped with permanent magnets 60.
  • the electric drive motor 10 and the inner rotor 9 connected to it and equipped with permanent magnets 90 are accommodated in the engine compartment.
  • the pot wall 20 has an edge 22 which is mounted sealingly in the pump housing 1 and constitutes the only sealing point of the canned pot 2 at the pump housing. 1
  • the pot base 21 of the canned pot 2 is connected in one piece to the pot wall 20, with the entire canned pot 2 preferably being made of electrically non-conductive ceramic material.
  • the pot base 21 is arched towards the motor 10, which allows the pump impeller 5 to be balanced with the external rotor 6 in a favorable manner.
  • the pump impeller 5 is rotatably mounted on the stationary axis 7, this bearing being limited to a purely radial bearing.
  • An axial bearing is not necessary and is not provided: the axis 7 is fastened in the intake manifold 8 by means of supporting ribs 80, a ceramic sliding bearing 70 serving for the radial mounting of the pump impeller 5, and an external lubrication channel 75 through a supporting rib 80 and through the axis 7 to the ceramic Slide bearing 70 is guided. If the pump medium is unfavorable for bearing lubrication, external lubrication can take place.
  • the axis 7 has a generously dimensioned compensating channel 71, which has some front lateral openings 72 and a rear opening 73, so that the suction port 8 of the pump housing 1 located on the front 52 of the pump impeller 5 with that on the rear 53 of the pump impeller 5 located part of the pump chamber 3 is permeably connected by this channel 71 with low inertia for the pumped medium.
  • the pump impeller 5 of the illustrated type of a radial pump has a front suction opening 50 and radial channels 51 which lead to the pressure connection 11 of the pump housing 1 are arranged to promote.
  • the pump impeller 5 is otherwise free of openings.
  • the pump chamber located in front of the pump impeller is connected to the suction nozzle 8 and to the pressure nozzle 11 and the rear part of the pump chamber to the pressure nozzle 11 in a medium-conducting manner.
  • 5 throttle rings 520 and 530 are provided on the pump impeller 5 on the front 52 and on the rear 53 of the pump impeller, respectively, which allow a balanced axial self-adjustment of the pump impeller 5 to be optimized for the intended purpose.
  • the rear throttle ring 530 is held by a retaining ring 531 and has no counterpart on the pot base 21, which does not mean, however, that a counter ring should not be attached if necessary.
  • a counter ring 521 is fastened to the pump housing 1 close to the axis by means of retaining ring 522.
  • the operating conditions can also be taken into account with a throttle screw 74 which is designed as a grub screw in a rib 80 and is accessible from the outside and through which the free passage in the channel 71 can be changed.
  • the intended emergency running properties of the throttle rings 520/521 and 530 are used at most in exceptional cases if, due to extraordinary events, the pump impeller 5 travels a somewhat larger axial path than is planned in the axial mobility. Otherwise the pressure equalization through channel 71 acts so spontaneously that even violent pressure fluctuations can be absorbed.
  • the throttle rings have an optimized, regulating effect on the desired operating center position of the pump impeller 7.

Abstract

In a centrifugal pump containing a sealing shroud the pump impeller is mounted only radially for rotation on a stationary axle or shaft. The stationary axle or shaft is fixed in the suction connection by means of wing rib supports or ribs and possesses an equalizing channel which connects the pump chamber portion at the rear of the pump impeller with the suction connection. This pump chamber portion at the rear of the pump impeller is connected with the delivery or pressure connection, whereas the pump chamber portion at the front side of the pump impeller is also connected with the suction connection as well as with the delivery or pressure connection. Advantageously, throttling rings are provided for self-metering throughflow throttling, depending on the axial position of the pump impeller. Additionally, the throughflow can be regulated by a throttling screw which is provided for the equalizing channel. In this way the pump impeller requires no axial or thrust bearing and can automatically adjust itself to variable requirements within a predetermined range.

Description

Die Erfindung betrifft eine Kreiselpumpe nach dem Oberbegriff des Anspruch 1.The invention relates to a centrifugal pump according to the preamble of claim 1.

Derartige Kreiselpumpen sind aus der DE-OS 26 20 502 bekannt, wobei die Achse mindestens teilweise am Spaltrohrtopfboden gehaltert ist, was eine unerwünschte mechanische Beanspruchung des Spaltrohrtopfes mit sich bringen kann und Schwierigkeiten beim Ausgleich von Druckunterschieden hinter und vor dem Pumpenlaufrad mit sich bringen kann.Such centrifugal pumps are known from DE-OS 26 20 502, the axis being at least partially held on the canned pot bottom, which can result in undesirable mechanical stress on the canned pot and can cause difficulties in equalizing pressure differences behind and in front of the pump impeller.

Bei mit der Welle umlaufenden Pumpenlaufrädern einer Spaltrohrpumpe (ohne Topfboden) ist es bereits bekannt die Druckunterschiede teilweise auszugleichen, soweit sie nicht zur Förderung eines Nebenstromes zur Kühlung und zum Schmieren des hinteren Lagers benötigt werden. Dazu hat man Ausgleichsöffnungen in das Pumpenlaufrad gemacht, welche von der Pumpenlaufrad-Hinterseite in das Innere des Pumpenlaufrades hineinreichen. Dass diese mit Leistungsverlusten verbunden ist und die Aufnahme der verbleibenden Axialkräfte durch Axiallager nötig macht geht aus allen Vorveröffentlichungen hervor, vgl. z.B. DE-OS 27 33 631, CH-PS 529 929 und EP-A1 0 078 345.In the case of pump impellers rotating around the shaft of a canned pump (without a pot bottom), it is already known to partially compensate for the pressure differences insofar as they are not required to promote a secondary flow for cooling and lubricating the rear bearing. For this purpose, compensation openings have been made in the pump impeller, which extend from the rear of the pump impeller into the interior of the pump impeller. All previous publications show that this is associated with a loss of power and necessitates the absorption of the remaining axial forces by axial bearings, cf. e.g. DE-OS 27 33 631, CH-PS 529 929 and EP-A1 0 078 345.

Es ist dabei in der DE-OS 27 33 631 vorgesehen die schwankenden Axialkräfte durch Steuerung des Durchlasses der Ausgleichsöffnung des Pumpenlaufrades auszugleichen, was zumindest zu unerwünschten Störungen der Laufradströmung und zu Leistungsverlusten führen kann.It is provided in DE-OS 27 33 631 to compensate for the fluctuating axial forces by controlling the passage of the compensating opening of the pump impeller, which can at least lead to undesired disturbances in the impeller flow and to loss of performance.

In der EP-A1 0 078 345 wiederum ist sogar ein Steuerapparat zur Steigerung des Querschnittes von Ausgleichsöffnungen im Pumpengehäuse vorgesehen, welcher von der Axiallage der Welle her gesteuert wird. Bei der CH-PS 529 929 werden verachleissbare Axialhauptlager und Axielhilfalager vorgesehen, deren Verschleiss unter gewissen Betriebsbedingungen eine Axial-Lageverschiebung des Pumpenlaufrades erlauben, die eine Axialkraftminderung zu Folge haben soll. Soweit das überhaupt geht, ist bei sich ändernden Betriebsbedingungen, und das ist nicht gerade selten der Fall, immer wieder ein neuer Verschleiss und ein neues "Einlaufen" nötig, das schliesslich zum totalen Verschleiss der Axiallager führen muss.EP-A1 0 078 345, in turn, even provides a control device for increasing the cross section of compensation openings in the pump housing, which is from the axial position of the shaft is controlled. In CH-PS 529 929, wearable axial main bearings and axial auxiliary bearings are provided, the wear of which allows the axial displacement of the pump impeller under certain operating conditions, which should result in a reduction in axial force. As far as that is possible, and with changing operating conditions, and this is not infrequently the case, new wear and a new "run-in" is always necessary, which must ultimately lead to total wear of the thrust bearings.

Der Erfindung liegt die Aufgabe zugrunde diese Nachteile zu vermeiden, wobei die kurze stationäre Achse im Vergleich zu den langen mitlaufenden Wellen schon den Vorteil hat, dass man nicht die Schmierung eines weit motorseitig entfernt angeordneten Lagers berücksichtigen muss.The invention is based on the object of avoiding these disadvantages, the short stationary axis already having the advantage in comparison to the long idling shafts that one does not have to take into account the lubrication of a bearing located far away from the motor.

Ausgleichsöffnungen in das Innere des Pumpenlaufrades haben sich nicht als ausreichend vorteilhaft gezeigt und die Steuerung der Durchlässe nach Axiallage ergab dabei auch keine brauchbare Verbesserung.Compensating openings in the interior of the pump impeller have not proven to be sufficiently advantageous, and the control of the passages according to the axial position did not result in any useful improvement.

Angestrebt wurde eine möglichst einfache wirtschaftliche und wartungsfreundliche Konstruktion.The aim was to have a construction that was as simple and economical as possible and easy to maintain.

Ueberraschenderweise wurde nun gefunden, dass sich ein gut beherrschbarer, praktisch verzögerungsfreier bzw. trägheitsarmer Druckausgleich durch die hohle Achse bewirken lässt, ohne dass man Ausgleichsöffnungen am Pumpenlaufrad selbst benötigt.Surprisingly, it has now been found that a well controllable, practically instantaneous or low-inertia pressure compensation can be achieved through the hollow axis without the need for compensation openings on the pump impeller itself.

Diese Ausgleichswirkung ist so hervorragend, dass man auf eine Axiallagerung des Pumpenlaufrades ganz verzichten kann, wenn man sowohl den Raum hinter als auch vor dem Pumpenlaufrad mit dem Ansaugstutzen und mit dem Druckstutzen mediumleitend, z.B. flüssigkeitsleitend verbindet, wobei durch die Axiallage des Pumpenlaufrades die Grösse der Durchlassquerschnitte veränderlich ist und den erwünschten Ausgleich selbsttätig erreichen lässt.This balancing effect is so excellent that you can do without an axial bearing of the pump impeller if you use both the space behind and in front of the pump impeller with the intake and pressure ports to conduct the medium, e.g. connects in a liquid-conducting manner, the size of the passage cross-sections being variable due to the axial position of the pump impeller and allowing the desired compensation to be achieved automatically.

Damit dies auch bei vorübergehend ungünstigen Laufbedingungen nicht zu einem direkten Kontakt des Pumpenlaufrades mit dem Pumpengehäuse führt, ist es vorteilhaft Droaselringe vorzusehen, die vordereeitig und hinterseitig am Laufrad angebracht sind und sich vorderseitig vorzugsweise nahe der Achse befinden. Wenigstens vorderaeitig ist auch ein Gegenring am Gehäuse vorzuziehen, während rückseitig der Topfboden als Notabstützung dienen kann. Diese Ringe können vorteilhafterweise Notlaufeigenachaften haben und z.B. aus Polytetrafluoräthylen bestehen, das chemisch beständig und gut selbstschmierend ist.It is advantageous that this does not result in direct contact of the pump impeller with the pump housing even under temporarily unfavorable running conditions To provide droasel rings, which are attached to the front and rear of the impeller and are preferably located near the axle on the front. At least on the front, a mating ring on the housing is preferable, while on the back the bottom of the pot can serve as an emergency support. These rings can advantageously have emergency running properties and consist, for example, of polytetrafluoroethylene, which is chemically stable and is well self-lubricating.

Die Drosselringewerden aber kaum je im normalen Betrieb zur Anlage kommen, da sie voneinander bzw. vom Topfboden durch eine dämpfende Mediumschicht getrennt sind und bei extremen Bewegungen des Pumpenlaufradee in eine Richtung eine augenblickliche Ausgleichawirkung abfangend und rückregulierend wirken wird.However, the throttle rings will hardly ever come into contact in normal operation, since they are separated from each other or from the bottom of the pot by a damping medium layer and, in the event of extreme movements of the pump impeller in one direction, will intercept and immediately regulate the balancing effect.

Die Erfindung wird nachstehend beispielsweise anhand der rein schematischen Zeichnung näher besprochen. Es zeigen:

  • Fig. 1 eine Ansicht einer erfindungsgemässen Pumpe von der Ansaugseite her, und
  • Fig. 2 einen Längsschnitt durch die Pumpe.
The invention is discussed in more detail below, for example, using the purely schematic drawing. Show it:
  • Fig. 1 is a view of an inventive pump from the suction side, and
  • Fig. 2 shows a longitudinal section through the pump.

Im Pumpengehäuse 1 ist ein Spaltrohrtopf 2 so dicht eingesetzt, dass der Spaltrohrtopf 2 den Pumpenraum 3 vom Motorraum 4 dicht und ohne bewegliche Dichtungen trennt.A canned pot 2 is inserted so tightly in the pump housing 1 that the canned pot 2 separates the pump chamber 3 from the motor chamber 4 in a sealed manner and without any movable seals.

Im Pumpenraum 3 ist das Pumpenlaufrad 5 mit dem zugehörigen, mit Permanentmagneten 60 bestückten Aussenläufer 6 verbunden untergebracht.In the pump chamber 3, the pump impeller 5 is housed connected to the associated external rotor 6 equipped with permanent magnets 60.

Im Motorraum ist der elektrische Antriebsmotor 10 und der mit ihm verbundene, mit Permanentmagneten 90 bestückte Innenläufer 9 untergebracht.The electric drive motor 10 and the inner rotor 9 connected to it and equipped with permanent magnets 90 are accommodated in the engine compartment.

Es liegt hier also eine Umkehrung der Zuordnung der mit Permanentmagneten bestückten Läufer gegenüber der üblichen Konstruktion und eine Umkehr der Anordnung des Spaltrohrtopfes 2 vor, was es ermöglicht, die das Spaltrohr bildende Topfwand 20 mindestens angenähert nur mit Druckkräften zu beaufschlagen, was sich auf die Gesamtkonstruktion vorteilhaft auswirkt, und was Gegenstand einer am gleichen Tage mit Anwaltszeichen 7074 eingereichten Patentanmeldung ist.There is therefore a reversal of the assignment of the runners equipped with permanent magnets compared to the usual construction and a reversal of the arrangement of the canned pot 2, which makes it possible to at least approximate the pot wall 20 forming the canned pipe only To apply compressive forces, which has an advantageous effect on the overall construction, and which is the subject of a patent application filed on the same day with the legal number 7074.

Die Topfwand 20 hat einen Rand 22, welcher im Pumpenge- häuse 1 dichtend gehaltert ist und die einzige Dichtungsstelle des Spaltrohrtopfes 2 am Pumpengehäuse 1 darstellt.The pot wall 20 has an edge 22 which is mounted sealingly in the pump housing 1 and constitutes the only sealing point of the canned pot 2 at the pump housing. 1

Der Topfboden 21 des Spaltrohrtopfes 2 ist einstückig mit der Topfwand 20 verbunden, wobei hier beispielsweise der ganze Spaltrohrtopf 2 bevorzugterweise aus elektrisch nicht leitendem keramischen Material besteht.The pot base 21 of the canned pot 2 is connected in one piece to the pot wall 20, with the entire canned pot 2 preferably being made of electrically non-conductive ceramic material.

Der Topfboden 21 ist gegen den Motor 10 hin eingewölbt, was eine günstige Ausbalancierung des Pumpenlaufrades 5 mit dem Aussenläufer 6 gestattet.The pot base 21 is arched towards the motor 10, which allows the pump impeller 5 to be balanced with the external rotor 6 in a favorable manner.

Dabei ist das Pumpenlaufrad 5 auf der stationären Achse 7 drehbar gelagert, wobei sich diese Lagerung auf eine reine Radiallagerung beschränkt. Eine Axiallagerung ist nicht nötig und nicht vorgesehen: Die Achse 7 ist im Ansaugstutzen 8 mittels Tragrippen 80 befestigt, wobei ein Keramikgleitlager 70 der radialen Lagerung des Pumpenlaufrades 5 dient, und wobei ein Fremdschmierkanal 75 durch eine Tragrippe 80 und durch die Achse 7 zum Keramik-Gleitlager 70 geführt ist. Bei für die Lagerschmierung ungünstigem Pumpmedium kann so eine Fremdschmierung erfolgen.The pump impeller 5 is rotatably mounted on the stationary axis 7, this bearing being limited to a purely radial bearing. An axial bearing is not necessary and is not provided: the axis 7 is fastened in the intake manifold 8 by means of supporting ribs 80, a ceramic sliding bearing 70 serving for the radial mounting of the pump impeller 5, and an external lubrication channel 75 through a supporting rib 80 and through the axis 7 to the ceramic Slide bearing 70 is guided. If the pump medium is unfavorable for bearing lubrication, external lubrication can take place.

Die Achse 7 hat einen grosszügig dimensionierten dem Ausgleich dienenden Kanal 71, welcher einige vordere seitliche Oeffnungen 72 und eine hintere Oeffnung 73 aufweist, so dass der an der Vorderseite 52 des Pumpenlaufrades 5 befindliche Ansaugstutzen 8 des Pumpengehäuses 1 mit dem an der Hinterseite 53 des Pumpenlaufrades 5 befindlichen Teil des Pumpenraumes 3 durch diesen Kanal 71 trägheitsarm für das gepumpte Medium durchlässig verbunden ist.The axis 7 has a generously dimensioned compensating channel 71, which has some front lateral openings 72 and a rear opening 73, so that the suction port 8 of the pump housing 1 located on the front 52 of the pump impeller 5 with that on the rear 53 of the pump impeller 5 located part of the pump chamber 3 is permeably connected by this channel 71 with low inertia for the pumped medium.

Das Pumpenlaufrad 5 der gezeichneten Bauart einer Radialpumpe hat eine vordere Ansaugöffnung 50 und Radialkanäle 51, welche zum Druckstutzen 11 des Pumpengehäuses 1 fördernd angeordnet sind. Das Pumpenlaufrad 5 ist sonst frei von Oeffnungen. Dabei ist der vor dem Pumpenlaufrad befindliche Pumpenraum mit dem Ansaugstutzen 8 und mit dem Druckstutzen 11 und der hintere Pumpenraumteil mit dem Druckstutzen 11 mediumleitend verbunden.The pump impeller 5 of the illustrated type of a radial pump has a front suction opening 50 and radial channels 51 which lead to the pressure connection 11 of the pump housing 1 are arranged to promote. The pump impeller 5 is otherwise free of openings. The pump chamber located in front of the pump impeller is connected to the suction nozzle 8 and to the pressure nozzle 11 and the rear part of the pump chamber to the pressure nozzle 11 in a medium-conducting manner.

Wenn die Pumpe in Betrieb ist, kann sich deshalb ein sich hinter dem Pumpenlaufrad aufbauender Druck mit einem sich vor dem Pumpenlaufrad aufbauenden unterschiedlichen Druck trägheitsarm ausgleichen, so dass das Pumpenlaufrad 5 keiner axialen Lagerung bedarf und selbstzentriert läuft.When the pump is in operation, a pressure building up behind the pump impeller can therefore compensate for low inertia with a different pressure building up in front of the pump impeller, so that the pump impeller 5 requires no axial bearing and runs self-centered.

Nun sind aber verschiedene Pumpen für ganz bestimmte Zwecke mit ganz bestimmten Eigenschaften ausgestattet, und es können auch gewisse Unterschiede in den Betriebsbedingungen auftreten.Now, however, various pumps are equipped with very specific properties for very specific purposes, and certain differences in the operating conditions can also occur.

Der Zweckbestimmung entsprechend sind an der Vorderseite 52 bzw. an der Rückseite 53 des Pumpenlaufrades 5 Drosselringe 520 bzw. 530 am Pumpenlaufrad 5 vorgesehen, welche ein ausgeglichenes axiales Selbsteinstellen des Pumpenlaufrades 5 zweckbestimmungsmässig optimieren lassen. Der rückseitige Drosselring 530 wird von einem Haltering 531 gehaltert und hat kein Gegenstück am Topfboden 21, was aber nicht heisst, dass man dort nötigenfalls keinen Gegenring anbringen dürfte. Dagegen ist am Pumpengehäuse 1 achsnah ein Gegenring 521 mittels Haltering 522 befestigt.In accordance with the intended use, 5 throttle rings 520 and 530 are provided on the pump impeller 5 on the front 52 and on the rear 53 of the pump impeller, respectively, which allow a balanced axial self-adjustment of the pump impeller 5 to be optimized for the intended purpose. The rear throttle ring 530 is held by a retaining ring 531 and has no counterpart on the pot base 21, which does not mean, however, that a counter ring should not be attached if necessary. In contrast, a counter ring 521 is fastened to the pump housing 1 close to the axis by means of retaining ring 522.

Den Betriebsbedingungen kann man darüberhinaus mit einer als Madenschraube in einer Rippe 80 ausgebildeten und von aussen zugänglichen Drosselschraube 74 Rechnung tragen, durch welche der freie Durchgang im Kanal 71 veränderbar ist.The operating conditions can also be taken into account with a throttle screw 74 which is designed as a grub screw in a rib 80 and is accessible from the outside and through which the free passage in the channel 71 can be changed.

Höchstens ausnahmsweise kommen die vorgesehenen Notlaufeigenschaften der Drosselringe 520/521 und 530 zum Einsatz, wenn durch ausserordentliche Ereignisse das Pumpenlaufrad 5 einen etwas grösseren Axialweg zurücklegt, als dies in der Axialbeweglichkeit eingeplant ist. Sonst wirkt der Druckausgleich durch den Kanal 71 so spontan, dass selbst heftige Druckschwankungen abgefangen werden - können. Die Drosselringe wirken dabei zweckbestimmungsgemäss optimiert regulierend auf die gewünschte Betriebs-Mittellage des Pumpenlaufrades 7.The intended emergency running properties of the throttle rings 520/521 and 530 are used at most in exceptional cases if, due to extraordinary events, the pump impeller 5 travels a somewhat larger axial path than is planned in the axial mobility. Otherwise the pressure equalization through channel 71 acts so spontaneously that even violent pressure fluctuations can be absorbed. The throttle rings have an optimized, regulating effect on the desired operating center position of the pump impeller 7.

Während hier eine Radialpumpe gezeichnet wurde, kann die Erfindung auch bei anderen Kreiselpumpen nutzbringend angewendet werden, so z.B. bei Radial-Axial-Pumpen.While a radial pump has been drawn here, the invention can also be used to advantage in other centrifugal pumps, e.g. with radial-axial pumps.

Claims (9)

1. Kreiselpumpe mit einem ihr Pumpengehäuse antriebsseitig gegen ein gepumptes Medium dichtenden Spaltrohrtopf, auf dessen einer Seite ein motorgetriebener Permanentmagnet-Läufer angeordnet ist, während auf der anderen Topfseite ein zweiter Permanentmagnet-Läufer mit einem auf einer stationären Achse drehbaren Pumpenlaufrad mechanisch verbunden ist, wobei dieses Pumpenlaufrad seine Rückseite einem Topfboden des Spaltrohrtopfes zukehrt, während seine Vorderseite einem Ansaugstutzen des auch einen Druckstutzen aufweisenden Pumpengehäuses zugekehrt ist, dadurch gekennzeichnet , dass die stationäre Achse (7) im Ansaugstutzen (8) fliegend befestigt ist und einen Ausgleichskanal (71) aufweist, welcher vom Ansaugstutzen (8) zu einem hinter der Rückseite (53) des Pumpenlaufrades (5) liegenden hinteren Pumpenraumteil (31) führt, wobei das Pumpenlaufrad (5) nur radial gelagert ist, und wobei der hintere Pumpenraumteil (31) und ein den Ansaugstutzen (8) umgebender vorderer Pumpenraumteil (30) je mit dem Ansaugstutzen (8) und mit dem Druckstutzen (11) mediumleitend verbunden sind.1. Centrifugal pump with a canned tube sealing its pump housing on the drive side against a pumped medium, on one side of which a motor-driven permanent magnet rotor is arranged, while on the other side of the pot a second permanent magnet rotor is mechanically connected to a pump impeller rotatable on a stationary axis, whereby This pump impeller turns its rear side toward a pot bottom of the canned pot, while its front side faces an intake port of the pump housing, which also has a pressure port, characterized in that the stationary axis (7) is fixed in the intake port (8) and has a compensating channel (71), which leads from the intake port (8) to a rear pump chamber part (31) located behind the rear side (53) of the pump impeller (5), the pump impeller (5) being mounted only radially, and with the rear pump chamber part (31) and a the intake port (8) surrounding front pump chamber part (30) each are connected to the suction pipe (8) and the pressure pipe (11) in a medium-conducting manner. 2. Kreiselpumpe nach Anspruch 1, dadurch gekennzeichnet, dass das Pumpenlaufrad (5) zumindest auf einer Seite (52, 53) einen Drosselring (520, 530) aufweist, wobei vorzugsweise wenigstens dem vorderen Drosselring (520) gegenüberliegend ein Gehäusedrosselring (521) vorgesehen ist.2. Centrifugal pump according to claim 1, characterized in that the pump impeller (5) at least on one side (52, 53) has a throttle ring (520, 530), preferably at least the front throttle ring (520) opposite a housing throttle ring (521) is provided is. 3. Kreiselpumpe nach einem der Ansprüche 1 und 2, dadurch gekennzeichnet,.dass ein, vorzugsweise als Schraube ausgebildeter,Drosselkörper (74), vorzugsweise von aussen betätigbar, im Ausgleichskanal (71) verstellbar ist.3. Centrifugal pump according to one of claims 1 and 2, characterized in that a throttle body (74), preferably designed as a screw, can preferably be actuated from the outside, is adjustable in the compensating channel (71). 4. Kreiselpumpe nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass zu einem Gleitlager (70) des Pumpenlaufrades (5) ein sogenannter Fremdschmierkanal (75) durch die Achse (7) geführt ist.4. Centrifugal pump according to one of claims 1 to 3, characterized in that a so-called external lubrication channel (75) is guided through the axis (7) to a slide bearing (70) of the pump impeller (5). 5. Kreiselpumpe nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass Drosselringe (520, 521, 530) mit Notlaufeigenschaften vorgesehen sind.5. Centrifugal pump according to one of claims 1 to 4, characterized in that throttle rings (520, 521, 530) are provided with emergency running properties. 6. Kreiselpumpe nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass der Topfboden (21) von der Achse (7) unberührt und von ihr hinweggewölbt verläuft.6. Centrifugal pump according to one of claims 1 to 5, characterized in that the pot bottom (21) of the axis (7) is unaffected and curved away from it. 7. Kreiselpumpe nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass die Topfwand (20) vom Pumpenlaufrad (5) hinweglaufend vom Topfboden (21) absteht und vom mit dem Pumpenlaufrad (5) verbundenen Permanentmagnet-Läufer (60) wenigstens teilweise umgeben ist.7. Centrifugal pump according to one of claims 1 to 6, characterized in that the pot wall (20) from the pump impeller (5) protrudes from the pot base (21) and at least partially surrounds the permanent magnet rotor (60) connected to the pump impeller (5) is. 8. Kreiselpumpe nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass das Laufrad frei von Ausgleichsöffnungen ist.8. Centrifugal pump according to one of claims 1 to 7, characterized in that the impeller is free of compensation openings. 9. Kreiselpumpe nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass wenigstens ein vorderer Drosselring (520, 521) achsnah angeordnet ist.9. Centrifugal pump according to one of claims 1 to 8, characterized in that at least one front throttle ring (520, 521) is arranged close to the axis.
EP85105626A 1984-07-16 1985-05-08 Centrifugal pump with an isolating tubular air gap cap Expired EP0171515B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85105626T ATE29275T1 (en) 1984-07-16 1985-05-08 CENTRIFUGAL PUMP WITH CANNED TUBE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH345184 1984-07-16
CH3451/84 1984-07-16

Publications (2)

Publication Number Publication Date
EP0171515A1 true EP0171515A1 (en) 1986-02-19
EP0171515B1 EP0171515B1 (en) 1987-09-02

Family

ID=4256229

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85105626A Expired EP0171515B1 (en) 1984-07-16 1985-05-08 Centrifugal pump with an isolating tubular air gap cap

Country Status (5)

Country Link
US (1) US4645433A (en)
EP (1) EP0171515B1 (en)
JP (1) JPS6138192A (en)
AT (1) ATE29275T1 (en)
DE (1) DE3560533D1 (en)

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EP0237868A2 (en) * 1986-03-21 1987-09-23 Ernst Hauenstein Radial or axial flow centrifugal pump
WO1996032592A1 (en) * 1995-04-14 1996-10-17 Ceramiques & Composites S.A. Magnetic drive centrifugal pump
DE4238132C2 (en) * 1992-11-12 2002-10-24 Teves Gmbh Alfred Centrifugal pump, in particular water pump for motor vehicles
EP1329638A1 (en) * 2002-01-18 2003-07-23 CP Pumpen AG Magnetically coupled centrifugal pump
WO2007112938A2 (en) * 2006-03-31 2007-10-11 H. Wernert & Co. Ohg Rotary pump with coaxial magnetic coupling

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US5039061A (en) * 1990-01-26 1991-08-13 John H. Carter Co., Inc. Magnetically actuated linear valve operator and method
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US5659205A (en) * 1996-01-11 1997-08-19 Ebara International Corporation Hydraulic turbine power generator incorporating axial thrust equalization means
US5779456A (en) * 1996-10-28 1998-07-14 Finish Thompson Inc. Magnetic drive
US6293772B1 (en) 1998-10-29 2001-09-25 Innovative Mag-Drive, Llc Containment member for a magnetic-drive centrifugal pump
US7682301B2 (en) * 2003-09-18 2010-03-23 Thoratec Corporation Rotary blood pump
JP4679261B2 (en) * 2005-06-24 2011-04-27 日本電産サンキョー株式会社 Magnetic coupling pump device
EP2005376A2 (en) * 2006-03-31 2008-12-24 Orqis Medical Corporation Rotary blood pump
BRPI0923965B1 (en) * 2009-01-09 2020-01-28 Sulzer Management Ag centrifugal pump with a device for removing particles
US8905729B2 (en) 2011-12-30 2014-12-09 Peopleflo Manufacturing, Inc. Rotodynamic pump with electro-magnet coupling inside the impeller
US8905728B2 (en) 2011-12-30 2014-12-09 Peopleflo Manufacturing, Inc. Rotodynamic pump with permanent magnet coupling inside the impeller
CN102966557A (en) * 2012-11-07 2013-03-13 无锡惠山泵业有限公司 Clean water pump
US9771938B2 (en) * 2014-03-11 2017-09-26 Peopleflo Manufacturing, Inc. Rotary device having a radial magnetic coupling
AU2017353926B2 (en) * 2016-11-01 2020-04-30 Psg Worldwide, Inc. Magnetically coupled sealless centrifugal pump
CN107313974A (en) * 2017-07-04 2017-11-03 安徽腾龙泵阀制造有限公司 A kind of separation sleeve for improving magnetic drive pump stability

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EP0237868A3 (en) * 1986-03-21 1988-01-20 Ernst Hauenstein Radial or axial flow centrifugal pump
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Also Published As

Publication number Publication date
DE3560533D1 (en) 1987-10-08
ATE29275T1 (en) 1987-09-15
JPH0562240B2 (en) 1993-09-08
JPS6138192A (en) 1986-02-24
EP0171515B1 (en) 1987-09-02
US4645433A (en) 1987-02-24

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