EP0478882A1 - Stator for a turbomolecular pump - Google Patents

Stator for a turbomolecular pump Download PDF

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Publication number
EP0478882A1
EP0478882A1 EP91105817A EP91105817A EP0478882A1 EP 0478882 A1 EP0478882 A1 EP 0478882A1 EP 91105817 A EP91105817 A EP 91105817A EP 91105817 A EP91105817 A EP 91105817A EP 0478882 A1 EP0478882 A1 EP 0478882A1
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EP
European Patent Office
Prior art keywords
stator
spacer rings
ring
stator according
spacer
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
EP91105817A
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German (de)
French (fr)
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EP0478882B1 (en
Inventor
Rainer Hölzer
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.)
Balzers und Leybold Deutschland Holding AG
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Leybold AG
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Publication date
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Publication of EP0478882A1 publication Critical patent/EP0478882A1/en
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Publication of EP0478882B1 publication Critical patent/EP0478882B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • F04D19/00—Axial-flow pumps
    • F04D19/02—Multi-stage pumps
    • F04D19/04—Multi-stage pumps specially adapted to the production of a high vacuum, e.g. molecular pumps
    • F04D19/042—Turbomolecular vacuum 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
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/52—Casings; Connections of working fluid for axial pumps
    • F04D29/54—Fluid-guiding means, e.g. diffusers
    • F04D29/541—Specially adapted for elastic fluid pumps
    • F04D29/542—Bladed diffusers
    • 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
    • F04D29/60—Mounting; Assembling; Disassembling
    • F04D29/64—Mounting; Assembling; Disassembling of axial pumps
    • F04D29/644—Mounting; Assembling; Disassembling of axial pumps especially adapted for elastic fluid pumps

Definitions

  • the invention relates to a stator for a turbomolecular vacuum pump with spacer rings and with partial ring disks carrying the stator blades, which are arranged with an outer edge between the spacer rings.
  • the structure of stators for turbomolecular vacuum pumps is described in DE OS 22 14 702.
  • the known stators include spacer rings and blade ring disks.
  • the blade ring disks have outer edge areas. Characterized in that the outer edge of a blade ring disk is clamped between two spacer rings, the ring disks and thus the stator blades are securely held in the pump.
  • the rotors of turbomolecular vacuum pumps are generally designed in one piece.
  • a turbomolecular vacuum pump with a one-piece rotor is assembled in such a way that the stator is built “around the rotor” by inserting the partial stator ring disks into the region of the rotor blades from the side.
  • stator disks Since the blades of the stator ring disks protrude into the space between the rotor blades, the stator disks must be designed as partial, preferably half ring disks. They are brought into position from the side.
  • the pump housing is pushed onto the fully assembled stator in such a way that it surrounds the stator.
  • the housing can be used to ensure that the stator core is centered. As a rule, however, means (centering edges, bolts, etc.) are provided which cause the stator to self-center.
  • stator half-washers When installing stators of this type, it always happens that two stator half-washers are not placed exactly on the associated spacer ring, in such a way that the half-ring discs overlap in a joint area. The consequence of such incorrect assembly is an oblique structure of the stator package.
  • the object of the present invention is to design the stator for a turbomolecular vacuum pump of the type mentioned at the outset in such a way that there is no longer any risk of incorrect assembly of the type described.
  • this object is achieved in that the outer edge of the partial stator ring washers is flanged and that the spacer rings are equipped with a corresponding, circumferential, receiving the flanged edge recess. If two partial ring washers are placed on a spacer ring in such a way that they overlap in a joint area during the assembly of a stator of this type, the step which is formed as a result is relatively high because of the flanged edge and is therefore immediately noticeable to the fitter. He is thus able to correct an incorrect placement of the ring washers immediately. There is no longer any danger of the stator being built up at an angle.
  • Figures 1 to 5 each show in cross section two spacer rings 1 and 2. They are designed in a manner known per se as profile rings and have mutually corresponding projections and recesses, which are not described in detail, and which bring about self-centering of the assembled stator package. Between the spacer rings is the outer edge of a partial ring, preferably semi-annular disc 3, which carries inwardly directed stator blades, not shown in detail.
  • FIG. 6 shows an enlarged section through the outer edge of the partial ring disk 3.
  • the outer edge of the ring washer 3 is flanged (flanged edge 4).
  • a peripheral groove or recess 5 is assigned to this edge 4 in the respectively associated spacer ring 2. In the assembled state of the stator, the flanged edge 4 is located therein.
  • the spacer rings 1, 2 have in the exemplary embodiments according to FIGS. 1 to 4 and inner axially directed surface areas 7, 8 and 9, 10 with different functions.
  • the outer surface areas 7 (downward axial surface area) and 8 (upward axial surface area) lie against one another and determine the distance between the inner axial surface areas 9, 10.
  • the system is indirectly ensured by the spacer ring 11.
  • the distance between the axial n surface areas 9, 10 is chosen so large that a space 6 is created which is sufficiently large to accommodate the outer edge of the annular disk 3. This ensures that the outer surface areas 7, 8 - regardless of the thickness of the partial stator washers 3 - are assured, i.e. the stator structure becomes independent of the tolerance of the metal sheets used for the stator washers 3.
  • the ring washers 3 may be appropriate to provide the ring washers 3 with one or more elevations 12 (Fig. 6). If these elevations (or a circumferential bead) are produced by embossing - for example at the same time as the stator blades are punched - a spring effect is created. This ensures that the partial ring disks 3 are clamped between the spacer rings 1, 2.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Non-Positive Displacement Air Blowers (AREA)

Abstract

The invention relates to the stator for a turbomolecular vacuum pump with spacer rings (1, 2) and with split washers (3), which carry the stator blades and are arranged with an outer edge between the spacer rings; in order to prevent incorrect assembly it is proposed that the outer edge of the split washers (3) be flanged and that the spacer rings (1, 2) be equipped with a corresponding recess (5) receiving the flanged edge (4).

Description

Die Erfindung bezieht sich auf einen Stator für eine Turbomolekularvakuumpumpe mit Distanzringen und mit die Statorschaufeln tragenden Teilringscheiben, die mit einem äußeren Rand zwischen den Distanzringen angeordnet sind.The invention relates to a stator for a turbomolecular vacuum pump with spacer rings and with partial ring disks carrying the stator blades, which are arranged with an outer edge between the spacer rings.

Der Aufbau von Statoren für Turbomolekularvakuumpumpen ist in der DE OS 22 14 702 beschrieben. Die vorbekannten Statoren umfassen Distanzringe und Schaufelringscheiben. Die Schaufelringscheiben weisen äußere Randbereiche auf. Dadurch, daß zwischen zwei Distanzringen jeweils der äußere Rand einer Schaufelringscheibe eingeklemmt ist, erfolgt eine sichere Halterung der Ringscheiben und damit der Statorschaufeln in der Pumpe. Ergänzend zu dem in der DE OS 22 14 702 beschriebenen Stand der Technik ist darauf hinzuweisen, daß die Rotoren von Turbomolekularvakuumpumpen in der Regel einstückig ausgebildet sind. Die Montage einer Turbomolekularvakuumpumpe mit einem einstückigen Rotor erfolgt in der Weise, daß der Stator "um den Rotor herum" aufgebaut wird, indem die Statorteilringscheiben von der Seite in den Bereich der Rotorschaufeln eingefügt werden. Das geschieht in der Weise, daß abwechselnd ein Distanzring und eine Schaufelringscheibe aufeinandergelegt werden. Da die Schaufeln der Statorringscheiben in den zwischen den Rotorschaufeln befindlichen Zwischenraum hineinragen, müssen die Statorscheiben als Teil-, vorzugsweise Halbringscheiben, ausgebildet sein. Sie werden von der Seite her in ihre Position gebracht. Auf den fertig montierten Stator wird das Pumpengehäuse derart aufgeschoben, daß es den Stator umgibt. Es besteht die Möglichkeit, mit dem Gehäuse die Zentrierung des Statorpakets sicherzustellen. In der Regel sind jedoch Mittel (Zentrierränder, Bolzen u.dgl.) vorgesehen, die eine Selbstzentrierung des Stators bewirken.The structure of stators for turbomolecular vacuum pumps is described in DE OS 22 14 702. The known stators include spacer rings and blade ring disks. The blade ring disks have outer edge areas. Characterized in that the outer edge of a blade ring disk is clamped between two spacer rings, the ring disks and thus the stator blades are securely held in the pump. In addition to the prior art described in DE OS 22 14 702, it should be pointed out that the rotors of turbomolecular vacuum pumps are generally designed in one piece. A turbomolecular vacuum pump with a one-piece rotor is assembled in such a way that the stator is built “around the rotor” by inserting the partial stator ring disks into the region of the rotor blades from the side. This is done in such a way that a spacer ring and a blade ring disc are placed alternately on top of one another. Since the blades of the stator ring disks protrude into the space between the rotor blades, the stator disks must be designed as partial, preferably half ring disks. They are brought into position from the side. The pump housing is pushed onto the fully assembled stator in such a way that it surrounds the stator. The housing can be used to ensure that the stator core is centered. As a rule, however, means (centering edges, bolts, etc.) are provided which cause the stator to self-center.

Bei der Montage von Statoren dieser Art kommt es immer wieder vor, daß zwei Statorhalbringscheiben nicht exakt auf den zugehörigen Distanzring aufgelegt werden, und zwar derart, daß sich die Halbringscheiben in einem Stoßbereich überlappen. Die Folge einer derartigen Fehlmontage ist ein schiefer Aufbau des Statorpaketes.When installing stators of this type, it always happens that two stator half-washers are not placed exactly on the associated spacer ring, in such a way that the half-ring discs overlap in a joint area. The consequence of such incorrect assembly is an oblique structure of the stator package.

Der vorliegenden Erfindung liegt die Aufgabe zugrunde, den Stator für eine Turbomolekularvakuumpumpe der eingangs genannten Art derart auszubilden, daß die Gefahr von Fehlmontagen der beschriebenen Art nicht mehr besteht.The object of the present invention is to design the stator for a turbomolecular vacuum pump of the type mentioned at the outset in such a way that there is no longer any risk of incorrect assembly of the type described.

Erfindungsgemäß wird diese Aufgabe dadurch gelöst, daß der äußere Rand der Statorteilringscheiben umgebördelt ist und daß die Distanzringe mit einer korrespondierenden, umlaufenden, den umgebördelten Rand aufnehmenden Aussparung ausgerüstet sind. Sollten bei der Montage eines Stators dieser Art zwei Teilringscheiben derart auf einen Distanzring gelegt werden, daß sie sich in einem Stoßbereich überlappen, dann ist die sich dadurch ausbildende Stufe wegen des umgebördelten Randes relativ hoch und fällt dadurch dem Monteur sofort auf. Er ist damit in der Lage, ein fehlerhaftes Auflegen der Teilringscheiben sofort zu korrigieren. Die Gefahr eines schiefen Aufbaus des Stators besteht nicht mehr.According to the invention, this object is achieved in that the outer edge of the partial stator ring washers is flanged and that the spacer rings are equipped with a corresponding, circumferential, receiving the flanged edge recess. If two partial ring washers are placed on a spacer ring in such a way that they overlap in a joint area during the assembly of a stator of this type, the step which is formed as a result is relatively high because of the flanged edge and is therefore immediately noticeable to the fitter. He is thus able to correct an incorrect placement of the ring washers immediately. There is no longer any danger of the stator being built up at an angle.

Weitere Vorteile und Einzelheiten der Erfindung sollen anhand von in den Figuren 1 bis 6 dargestellten Ausführungsbeispielen erläutert werden. Die Figuren 1 bis 5 zeigen jeweils im Querschnitt zwei Distanzringe 1 und 2. Sie sind in an sich bekannter Weise als Profilringe ausgebildet und weisen zueinander korrespondierende, im einzelnen nicht näher bezeichnete Vorsprünge und Aussparungen auf, die eine Selbstzentrierung des zusammengebauten Statorpaketes bewirken. Zwischen den Distanzringen befindet sich der äußere Rand einer Teilring-, vorzugsweise Halbringscheibe 3, die nach innen gerichtete, im einzelnen nicht dargestellte Statorschaufeln trägt. Figur 6 zeigt vergrößert einen Schnitt durch den äußeren Rand der Teilringscheibe 3.Further advantages and details of the invention will be explained on the basis of the exemplary embodiments shown in FIGS. 1 to 6. Figures 1 to 5 each show in cross section two spacer rings 1 and 2. They are designed in a manner known per se as profile rings and have mutually corresponding projections and recesses, which are not described in detail, and which bring about self-centering of the assembled stator package. Between the spacer rings is the outer edge of a partial ring, preferably semi-annular disc 3, which carries inwardly directed stator blades, not shown in detail. FIG. 6 shows an enlarged section through the outer edge of the partial ring disk 3.

Der äußere Rand der Teilringscheibe 3 ist jeweils umgebördelt (Bördelkante 4). Dieser Kante 4 ist im jeweils zugehörigen Distanzring 2 eine umlaufende Nut bzw. Aussparung 5 zugeordnet. Darin befindet sich im zusammengebauten Zustand des Stators die Bördelkante 4.The outer edge of the ring washer 3 is flanged (flanged edge 4). A peripheral groove or recess 5 is assigned to this edge 4 in the respectively associated spacer ring 2. In the assembled state of the stator, the flanged edge 4 is located therein.

Wegen des Vorhandenseins der Bördelkante 4 an den jeweiligen Halbringen 3 und den Nuten bzw. Aussparungen 5 an den Distanzringen 1, 2 kommt es bei der Montage von in dieser Weise ausgebildeten Statoren nicht mehr zu stirnseitigen Überlappungen der Statorteilringe 3. Die Gefahr eines windschiefen Aufbaus wegen derartiger Montagefehler besteht nicht mehr.Due to the presence of the flanged edge 4 on the respective half rings 3 and the grooves or recesses 5 on the spacer rings 1, 2, when the stators designed in this way are fitted, there is no longer any overlap of the stator partial rings 3 on the face side. The risk of skewed construction due to such assembly errors no longer exist.

Die Distanzringe 1, 2 weisen bei den Ausführungsbeispielen nach den Figuren 1 bis 4 und innere axial gerichtete Flächenbereiche 7, 8 und 9, 10 mit unterschiedlichen Funktionen auf. Die äußeren Flächenbereiche 7 (nach unten gerichteter axialer Flächenbereich) und 8 (nach oben gerichteter axialer Flächenbereich) liegen einander an und bestimmen den Abstand der inneren axialen Flächenbereiche 9, 10. Beim Ausführungsbeispiel nach Figur 4 ist die Anlage mittelbar durch den Abstandsring 11 sichergestellt. Der Abstand der axiale n Flächenbereiche 9, 10 ist so groß gewählt, daß ein Raum 6 entsteht, der ausreichend groß für die Aufnahme des äußeren Randes der Ringscheibe 3 ist. Dadurch ist die Anlage der äußeren Flächenbereiche 7, 8 - unabhängig von der Stärke der Statorteilringscheiben 3 - sichergestellt, d.h., der Statoraufbau wird unabhängig von der Toleranz der für die Statorringscheiben 3 verwendeten Bleche.The spacer rings 1, 2 have in the exemplary embodiments according to FIGS. 1 to 4 and inner axially directed surface areas 7, 8 and 9, 10 with different functions. The outer surface areas 7 (downward axial surface area) and 8 (upward axial surface area) lie against one another and determine the distance between the inner axial surface areas 9, 10. In the exemplary embodiment according to FIG. 4, the system is indirectly ensured by the spacer ring 11. The distance between the axial n surface areas 9, 10 is chosen so large that a space 6 is created which is sufficiently large to accommodate the outer edge of the annular disk 3. This ensures that the outer surface areas 7, 8 - regardless of the thickness of the partial stator washers 3 - are assured, i.e. the stator structure becomes independent of the tolerance of the metal sheets used for the stator washers 3.

Um einen allzu lockeren Sitz der Statorteilringscheiben 3 zwischen den Distanzringen 1, 2 zu vermeiden, kann es zweckmäßig sein, die Teilringscheiben 3 mit einer oder mehreren Erhebungen 12 (Fig. 6) zu versehen. Werden diese Erhebungen (oder auch eine umlaufende Sicke) durch Prägen - z.B. gleichzeitig mit dem Stanzen der Statorschaufeln - hergestellt, dann entsteht eine Federwirkung. Eine klemmende Halterung der Teilringscheiben 3 zwischen den Distanzringen 1, 2 ist dadurch sichergestellt.To make the stator ring washers 3 too loose between the spacer rings 1, 2 avoid, it may be appropriate to provide the ring washers 3 with one or more elevations 12 (Fig. 6). If these elevations (or a circumferential bead) are produced by embossing - for example at the same time as the stator blades are punched - a spring effect is created. This ensures that the partial ring disks 3 are clamped between the spacer rings 1, 2.

Eine weitere vorteilhafte Maßnahme besteht noch darin, daß die nach innen gerichteten Kanten 13, 14 der Distanzringe abgeschrägt sind. Dadurch erweitert sich der Raum 6 in Richtung der nicht dargestellten Statorschaufeln. In dieser Erweiterung findet bereits der Schaufelfuß der Statorschaufeln Platz, welcher zur Pumpwirkung noch nicht viel beiträgt. Nur die wirksamen Bereiche der Statorschaufeln liegen damit innerhalb des Strömungskanales der Pumpe.Another advantageous measure is that the inward edges 13, 14 of the spacer rings are beveled. This expands the space 6 in the direction of the stator blades, not shown. In this extension there is already space for the blade root of the stator blades, which does not yet contribute much to the pumping effect. Only the effective areas of the stator blades are thus within the flow channel of the pump.

Claims (8)

1. Stator für eine Turbomolekularpumpe mit Distanzringen (1, 2) und mit die Statorschaufeln tragenden Teilringscheiben (3), die mit einem äußeren Rand zwischen den Distanzringen angeordnet sind, dadurch gekennzeichnet, daß der äußere Rand der Teilringscheiben (3) umgebördelt ist und daß die Distanzringe (1, 2) mit einer korrespondierenden, die Bördelkante (4) aufnehmenden Aussparung (5) ausgerüstet ist.1. Stator for a turbomolecular pump with spacer rings (1, 2) and with the stator blades bearing ring washers (3) which are arranged with an outer edge between the spacer rings, characterized in that the outer edge of the ring washers (3) is flanged and that the spacer rings (1, 2) are equipped with a corresponding recess (5) receiving the flanged edge (4). 2. Stator nach Anspruch 1, dadurch gekennzeichnet, daß die Distanzringe (1, 2) innere (9, 10) und äußere (8, 9) im wesentlichen axial gerichtete Flächen aufweisen, die derart bemessen und einander zugeordnet sind, daß im zusammengefügten Zustand des Statorpaketes die äußeren Axialflächen (7, 8) einander anliegen und daß die inneren Axialflächen (9, 10) jeweils einen der Aufnahme der Ränder der Statorteilringscheiben (3) dienenden Raum (6) bilden.2. Stator according to claim 1, characterized in that the spacer rings (1, 2) inner (9, 10) and outer (8, 9) have substantially axially directed surfaces which are dimensioned and assigned to one another such that in the assembled state of the stator pack, the outer axial surfaces (7, 8) abut each other and that the inner axial surfaces (9, 10) each form a space (6) which serves to accommodate the edges of the stator partial annular disks (3). 3. Stator nach Anspruch 2, dadurch gekennzeichnet, daß die Aussparung (5) Bestandteil des Raumes (6) ist.3. Stator according to claim 2, characterized in that the recess (5) is part of the space (6). 4. Stator nach Anspruch 1, 2 oder 3, dadurch gekennzeichnet, daß die Ränder der Statorteilringscheiben (3) mit axial gerichteten, federnden Erhebungen (12) ausgerüstet sind.4. Stator according to claim 1, 2 or 3, characterized in that the edges of the stator ring washers (3) are equipped with axially directed, resilient elevations (12). 5. Stator nach Anspruch 2, 3 oder 4, dadurch gekennzeichnet, daß die äußeren Flächenbereiche (7, 8) einander mittelbar über einen Abstandsring (11) anliegen.5. Stator according to claim 2, 3 or 4, characterized in that the outer surface areas (7, 8) abut one another indirectly via a spacer ring (11). 6. Stator nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Distanzringe (1, 2) zueinander korrespondierende Vorsprünge und Aussparungen zum Zwecke der Selbstzentrierung des Statorpaketes aufweisen.6. Stator according to one of the preceding claims, characterized in that the spacer rings (1, 2) have mutually corresponding projections and recesses for the purpose of self-centering the stator package. 7. Stator nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet , daß die nach innen gerichteten Kanten (13, 14) der Distanzringe (1, 2) abgeschrägt sind.7. Stator according to one of claims 1 to 6, characterized in that the inwardly directed edges (13, 14) of the spacer rings (1, 2) are chamfered. 8. Stator nach Anspruch 7, dadurch gekennzeichnet, daß sich der Fuß der Statorschaufeln in dem Raum zwischen den abgeschrägten Kanten (13, 14) befindet.8. Stator according to claim 7, characterized in that the foot of the stator blades is in the space between the chamfered edges (13, 14).
EP91105817A 1990-09-29 1991-04-12 Stator for a turbomolecular pump Expired - Lifetime EP0478882B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE9013671U DE9013671U1 (en) 1990-09-29 1990-09-29 Stator for a turbomolecular vacuum pump
DE9013671U 1990-09-29

Publications (2)

Publication Number Publication Date
EP0478882A1 true EP0478882A1 (en) 1992-04-08
EP0478882B1 EP0478882B1 (en) 1994-05-25

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EP91105817A Expired - Lifetime EP0478882B1 (en) 1990-09-29 1991-04-12 Stator for a turbomolecular pump

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DE (2) DE9013671U1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997015760A1 (en) * 1995-10-20 1997-05-01 Leybold Vakuum Gmbh Friction vacuum pump with intermediate inlet
WO2001011242A1 (en) * 1999-08-07 2001-02-15 Leybold Vakuum Gmbh Stator ring for a turbomolecular vacuum pump
EP1130269A3 (en) * 2000-03-02 2002-10-30 Pfeiffer Vacuum GmbH Turbo-molecular pump
EP2607706A3 (en) * 2011-12-23 2014-04-09 Oerlikon Leybold Vacuum GmbH Vacuum pump
US8709070B2 (en) 2011-05-10 2014-04-29 Abbott Cardiovascular Systems Inc. Bioabsorbable scaffold with particles providing delayed acceleration of degradation
EP1918588A3 (en) * 2006-10-26 2015-05-20 Pfeiffer Vacuum Gmbh Stator disc for a turbo molecular pump

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE29717764U1 (en) * 1997-10-06 1997-11-20 Leybold Vakuum GmbH, 50968 Köln Stator for a turbomolecular vacuum pump
DE202008011489U1 (en) * 2008-08-28 2010-01-07 Oerlikon Leybold Vacuum Gmbh Stator-rotor arrangement for a vacuum pump and vacuum pump

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2214702A1 (en) * 1972-03-25 1973-09-27 Leybold Heraeus Gmbh & Co Kg TURBOMOLECULAR PUMP
DE2523390B1 (en) * 1975-05-27 1976-05-13 Pfeiffer Vakuumtechnik STATOR BRACKET FOR TURBO MOLECULAR PUMPS
GB2206648A (en) * 1987-07-04 1989-01-11 Pfeiffer Vakuumtechnik Turbo-molecular pumps

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2214702A1 (en) * 1972-03-25 1973-09-27 Leybold Heraeus Gmbh & Co Kg TURBOMOLECULAR PUMP
DE2523390B1 (en) * 1975-05-27 1976-05-13 Pfeiffer Vakuumtechnik STATOR BRACKET FOR TURBO MOLECULAR PUMPS
GB2206648A (en) * 1987-07-04 1989-01-11 Pfeiffer Vakuumtechnik Turbo-molecular pumps

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 8, no. 201 (M-325)(1638) 14. September 1984 & JP-A-59 090 796 ( SHIMAZU ) 25. Mai 1984 *
PATENT ABSTRACTS OF JAPAN vol. 9, no. 198 (M-404)(1921) 15. August 1985 & JP-A-60 062 692 ( HITACHI ) 10. April 1985 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997015760A1 (en) * 1995-10-20 1997-05-01 Leybold Vakuum Gmbh Friction vacuum pump with intermediate inlet
US6030189A (en) * 1995-10-20 2000-02-29 Leybold Vakuum Gmbh Friction vacuum pump with intermediate inlet
WO2001011242A1 (en) * 1999-08-07 2001-02-15 Leybold Vakuum Gmbh Stator ring for a turbomolecular vacuum pump
EP1130269A3 (en) * 2000-03-02 2002-10-30 Pfeiffer Vacuum GmbH Turbo-molecular pump
EP1918588A3 (en) * 2006-10-26 2015-05-20 Pfeiffer Vacuum Gmbh Stator disc for a turbo molecular pump
US8709070B2 (en) 2011-05-10 2014-04-29 Abbott Cardiovascular Systems Inc. Bioabsorbable scaffold with particles providing delayed acceleration of degradation
EP2607706A3 (en) * 2011-12-23 2014-04-09 Oerlikon Leybold Vacuum GmbH Vacuum pump

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Publication number Publication date
DE59101715D1 (en) 1994-06-30
EP0478882B1 (en) 1994-05-25
DE9013671U1 (en) 1992-01-30

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