EP0408792B1 - Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement - Google Patents

Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement Download PDF

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Publication number
EP0408792B1
EP0408792B1 EP89113318A EP89113318A EP0408792B1 EP 0408792 B1 EP0408792 B1 EP 0408792B1 EP 89113318 A EP89113318 A EP 89113318A EP 89113318 A EP89113318 A EP 89113318A EP 0408792 B1 EP0408792 B1 EP 0408792B1
Authority
EP
European Patent Office
Prior art keywords
pump
gas
pump according
inlet
rotor
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
EP89113318A
Other languages
German (de)
English (en)
Other versions
EP0408792A1 (fr
Inventor
Frank Fleischmann
Hans-Peter Dr. Kabelitz
Hans Kriechel
Martin Mühlhoff
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
Original Assignee
Leybold AG
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
Application filed by Leybold AG filed Critical Leybold AG
Priority to DE89113318T priority Critical patent/DE58905785D1/de
Priority to EP89113318A priority patent/EP0408792B1/fr
Priority to US07/554,721 priority patent/US5051060A/en
Priority to JP2190867A priority patent/JP2994005B2/ja
Publication of EP0408792A1 publication Critical patent/EP0408792A1/fr
Application granted granted Critical
Publication of EP0408792B1 publication Critical patent/EP0408792B1/fr
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
    • F04D29/00—Details, component parts, or accessories
    • F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/68—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers
    • F04D29/681—Combating cavitation, whirls, noise, vibration or the like; Balancing by influencing boundary layers especially adapted for elastic fluid 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
    • 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
    • F04D19/044—Holweck-type pumps
    • 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
    • F05B2250/00—Geometry
    • F05B2250/20—Geometry three-dimensional
    • F05B2250/25—Geometry three-dimensional helical
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/60—Fluid transfer
    • F05D2260/607—Preventing clogging or obstruction of flow paths by dirt, dust, or foreign particles
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S415/00—Rotary kinetic fluid motors or pumps
    • Y10S415/914—Device to control boundary layer

Definitions

  • the invention relates to a gas friction pump with at least one outlet-side thread stage with an annular gas delivery channel.
  • Friction pumps include molecular and turbomolecular vacuum pumps.
  • a moving rotor wall and a stationary stator wall are designed and spaced apart such that the impulses transmitted from the walls to gas molecules located between them have a preferred direction.
  • the rotor and / or stator wall are equipped with thread-like depressions or projections.
  • Turbomolecular pumps have interlocking rows of stator and rotor blades in the manner of a turbine. You need a backing pressure of around 10 ⁇ 2 mbar. In contrast, molecular pumps deliver pressures of up to 10 mbar and more, so that the effort required for generating the forevacuum is considerably less.
  • Friction pumps of the type mentioned at the outset are frequently used for evacuating chambers in which etching, coating or other vacuum treatment or manufacturing processes are carried out. These processes run the risk of solids getting into the pump. In some processes, there is even the possibility that such solids only occur during the compression of the gases, that is to say during the passage of the gases to be pumped out through the vacuum chamber. Examples are the formation of aluminum chloride in aluminum etching, ammonium chloride in coating processes, etc.
  • the content of DE-A-25 26 164 belongs to the prior art. From this document a turbomolecular vacuum pump with a bell-shaped rotor is known, which carries rotor blades on its outside. Inside the rotor bell is a stationary cylindrical insert, which has a helical groove on its outside facing the inner wall of the rotor. In the space between the fixed insert and the inner wall of the rotor bell, a bore 22 which penetrates the fixed insert opens. Gas can be admitted through this bore, in order to lower the high-vacuum end pressure of the turbomolecular vacuum pump.
  • the present invention has for its object to design a gas friction vacuum pump of the type mentioned in such a way that on the one hand dust deposits in the outlet area can be eliminated and / or avoided and on the other hand the risk of contamination of the working chamber connected to the pump with oil vapors no longer is available.
  • the pump is equipped with a purge gas inlet which extends over the circumference of the gas delivery channel.
  • a flushing of the regions directed downstream with respect to the flushing gas inlet that is to say in particular the critical steps near the outlet, can be achieved by flushing in a flushing gas pulse (preferably nitrogen) of the order of 100 mbar l / s at operating speed. If this process is repeated at suitable intervals, removal of the deposited dust can be ensured.
  • a constant inlet of a few (1 to 5) mbar l / s purge gas preferably in the final pressure mode, causes a sufficient molecular flow in the conveying direction, so that the backflow portion and thus the oil backflow is avoided.
  • a sharp edge over which the flushing gas flows, forms the outlet-side boundary of the inlet opening of the flushing gas into the gas delivery channel. This creates a flow wall that effectively stops the backflow of oil and transports the oil molecules to the outlet.
  • the friction pump 1 shown in FIG. 1 has a first housing part 2. Part of this first housing part 2 is the outer cylinder 3, which is equipped with the flange 4. With the help of the flange 4, the friction pump 1 is connected either directly or via an attachment flange 5 to the recipient to be evacuated.
  • the friction pump has a second housing part 6, which serves to hold the rotor 7 and the stator of the drive motor 8.
  • the rotor 7 is bell-shaped. It comprises the hub part 9 and the cylindrical section 10.
  • the second housing part 6 projects into the space 11 formed by the bell-shaped rotor 7, in which the drive motor 8 and at least the upper bearing of the two rotor bearings 12 are also located.
  • the outside of the rotor 7, together with the inside of the outer cylinder 3, forms the pump-active surfaces or the annular gas delivery channel 20.
  • the gases to be pumped are conveyed from the inlet 13 to the outlet 14.
  • a forevacuum pump, not shown, is connected to the outlet 14 during operation.
  • the two housing parts 2 and 6 are designed in such a way that they can be separated and joined together in a simple manner.
  • a locking ring 15 serves for mutual locking in the assembled state.
  • the rotor 7 is equipped with a central shaft 16, which is supported in the bearings 12.
  • the bearings 12 are in turn supported by annular disks 21, 22 in a cylindrical section 17 which is part of the second housing part 6.
  • the first housing part 2 has an inner cylindrical section 18 which immediately surrounds the cylindrical section 17 of the second housing part 6.
  • the cylindrical portion 17 is equipped with an edge 19 which is the upper end face of the cylindrical section 18 rests.
  • the cylindrical section 17 projects downward from the cylindrical section 18 or the first housing part 2, so that there is the possibility of locking the two housing parts 2 and 6 against one another with the aid of the clamping ring 15. After loosening the clamping ring 15, the unit consisting of the rotor 7 and the second housing part 6 can be pulled up out of the first housing part 2.
  • the cylindrical section 10 of the rotor 7 has a relatively thin wall, so that the rotating mass is small.
  • the threaded structures that produce the gases are part of the stator.
  • the two rings 52 and 53 are equipped on their inner sides with threaded structures 56 and 57. Together with the outer surface of the cylinder section 10 of the rotor 7, these cause the gases to be conveyed in the direction of the outlet 14.
  • the rings 51, 52, 53 are held in their position in the assembled state. After loosening the top flange 5, the unit consisting of the rotor 7 and the housing part 6 and then the rings 51, 52, 53 can first be pulled out of the housing part 3.
  • the ring 51 has a smooth inner surface.
  • the structures 58 which produce the gases are provided on the rotor itself. For example, they can be designed as described in European patent application 88116749.8. These structures are designed as webs, the width and pitch of which decrease from the suction side to the pressure side. Thereby this results in an effective filling level 51, 58 with improved delivery performance.
  • the cylindrical housing 3 is equipped with a radial bore 61 to which a purge gas line, not shown, can be connected.
  • the bore 61 opens into an annular channel 62, in which the purge gas collects, so that it can be fed uniformly over the entire circumference of the gas delivery channel 20.
  • the enlarged representation of the geometry of the flushing gas inlet in FIG. 2 shows that the flushing gas is supplied between the two threaded step rings 52 and 53.
  • the collecting channel 62 is formed by an inner groove 63 in the housing part 3.
  • one of the two rings 52, 53 is provided with approximately radially directed grooves or is knurled so that there is a passage gap 65 extending over the entire circumference.
  • This passage gap 65 is followed by a volume expansion 66, which is formed by taking back the lower edge of the ring 52 and its thread structure 56. This results in an inlet opening 67 which is wider than the passage gap 65 and extends over the entire circumference of the gas delivery channel 20.
  • the pumped gas molecules move in the annular gas delivery channel 20 in the direction of arrow 68.
  • the flushing gas passes through the bore 61 into the ring channel 62 and is distributed over the circumference of the pump. It then passes through the gap 65 at high speed and reaches the volume extension 66, in which it calms down in part. Since this calming is only possible towards the inlet side, the flow rate of the purge gas is maintained along the end face of the ring 53. This creates a "flow wall", which effectively retains oil creeping on the thread bases 69 in the direction of the inlet 70 as well as molecular backflows present in the area of the groove bottoms, indicated by the arrows 71. The molecules entrained by the purge gas are promoted towards the outlet.
  • a sharp-edged design of the transition 72 of the groove bases 69 to the inlet-side end face of the ring 53 promotes the desired effect.

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

Claims (9)

  1. Pompe à gaz à effet visqueux (1) comportant au moins un étage à filetage (10, 57) côté refoulement et un canal de refoulement de gaz (20) de forme annulaire, caractérisée en ce que pour l'évacuation de poussières ou de substances solides et/ou pour éviter un reflux d'huile, elle est équipée d'une entrée de gaz de rinçage s'étendant sur la périphérie du canal de refoulement de gaz (20).
  2. Pompe selon la revendication 1, caractérisée en ce qu'une arête vive (72) par dessus laquelle s'écoule le gaz de rinçage à vitesse élevée, forme la limite côté sortie, de l'ouverture d'entrée (67) du gaz de rinçage dans le canal de refoulement de gaz (20).
  3. Pompe selon la revendication 1 ou 2, caractérisée en ce que qu'il est prévu un canal de collecte (62) de forme annulaire, pour le gaz de rinçage.
  4. Pompe selon la revendication 3, caractérisée en ce qu'une fente de passage (65) de forme annulaire, se raccorde au canal de collecte (62) de forme annulaire.
  5. Pompe selon la revendication 4, caractérisée en ce que la fente de passage (65) se raccorde à une chambre de tranquillisation (66) s'étendant vers l'entrée dans la pompe.
  6. Pompe selon l'une des revendications précédentes, caractérisée en ce qu'elle comporte au moins deux étages à filetage (10, 56 et 10, 57) et en ce que l'entrée de gaz de rinçage se situe entre ces deux étages à filetage.
  7. Pompe selon la revendication 6, caractérisée en ce que sont prévus des anneaux séparés (52, 53) portant les structures (56, 57) produisant le refoulement du gaz.
  8. Pompe selon la revendication 7, caractérisée en ce que l'entrée de gaz de rinçage se trouve dans la zone de jointure (64) des deux anneaux (52, 53).
  9. Pompe selon la revendication 8, caractérisée en ce que l'une des faces frontales des anneaux (52, 53), se trouvant dans la zone de jointure (64), est munie d'un moletage ou d'un rainurage pour former la fente de passage (65).
EP89113318A 1989-07-20 1989-07-20 Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement Expired - Lifetime EP0408792B1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DE89113318T DE58905785D1 (de) 1989-07-20 1989-07-20 Gasreibungspumpe mit mindestens einer auslassseitigen gewindestufe.
EP89113318A EP0408792B1 (fr) 1989-07-20 1989-07-20 Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement
US07/554,721 US5051060A (en) 1989-07-20 1990-07-19 Gas friction pump having an outlet-side helical stage
JP2190867A JP2994005B2 (ja) 1989-07-20 1990-07-20 少なくとも１つの出口側のねじ段を備えたガス摩擦ポンプ

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP89113318A EP0408792B1 (fr) 1989-07-20 1989-07-20 Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement

Publications (2)

Publication Number Publication Date
EP0408792A1 EP0408792A1 (fr) 1991-01-23
EP0408792B1 true EP0408792B1 (fr) 1993-09-29

Family

ID=8201651

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89113318A Expired - Lifetime EP0408792B1 (fr) 1989-07-20 1989-07-20 Pompe à effet visqueux avec au moins un étage hélicoidal à côté du refoulement

Country Status (4)

Country Link
US (1) US5051060A (fr)
EP (1) EP0408792B1 (fr)
JP (1) JP2994005B2 (fr)
DE (1) DE58905785D1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19804768B4 (de) * 1998-02-06 2006-08-24 Pfeiffer Vacuum Gmbh Rotorlagerung für eine Gasreibungspumpe

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4216237A1 (de) * 1992-05-16 1993-11-18 Leybold Ag Gasreibungsvakuumpumpe
JPH0886298A (ja) * 1994-09-19 1996-04-02 Hitachi Ltd ドライターボ真空ポンプ
DE19508566A1 (de) * 1995-03-10 1996-09-12 Balzers Pfeiffer Gmbh Molekularvakuumpumpe mit Kühlgaseinrichtung und Verfahren zu deren Betrieb
DE29516599U1 (de) * 1995-10-20 1995-12-07 Leybold Ag Reibungsvakuumpumpe mit Zwischeneinlaß
DE19632874A1 (de) 1996-08-16 1998-02-19 Leybold Vakuum Gmbh Reibungsvakuumpumpe
DE19809957A1 (de) * 1998-03-07 1999-09-09 Pfeiffer Vacuum Gmbh Mehrwellenvakuumpumpe
FR2783883B1 (fr) 1998-09-10 2000-11-10 Cit Alcatel Procede et dispositif pour eviter les depots dans une pompe turbomoleculaire a palier magnetique ou gazeux
US6193461B1 (en) 1999-02-02 2001-02-27 Varian Inc. Dual inlet vacuum pumps
DE19933332A1 (de) * 1999-07-16 2001-01-18 Leybold Vakuum Gmbh Reibungsvakuumpumpe für den Einsatz in einem System zur Druckregelung sowie Druckregelungssystem mit einer Reibungsvakuumpumpe dieser Art
US7025576B2 (en) 2001-03-30 2006-04-11 Chaffee Robert B Pump with axial conduit
SG152903A1 (en) * 2000-05-17 2009-06-29 Chaffee Robert B Inflatable device with recessed fluid contoller and modified adjustment device
CA2744867C (fr) 2001-07-10 2012-09-04 Robert Chaffee Dispositifs supports pneumatiques configurables
DE10136022B4 (de) * 2001-07-24 2006-01-12 Robert Bosch Gmbh Verfahren zur Vermeidung oder Beseitigung von Ausscheidungen im Abgasbereich einer Vakuumanlage
ATE333618T1 (de) * 2002-05-03 2006-08-15 Robert B Chaffee Selbstschliessendes ventil mit elektromechanischer vorrichtung zur betätigung des ventils
AU2003295748A1 (en) 2002-11-18 2004-06-15 Robert B. Chaffee Inflatable device
US20050079077A1 (en) * 2003-06-09 2005-04-14 Tsai Jing Hong Reversible inflation system
US7588425B2 (en) * 2005-03-18 2009-09-15 Aero Products International, Inc. Reversible inflation system
US20070077153A1 (en) * 2005-09-30 2007-04-05 Austen Timothy F Rechargeable AC/DC pump
US8033797B2 (en) * 2007-05-17 2011-10-11 The Coleman Company, Inc. Pump with automatic deactivation mechanism
US9336990B2 (en) * 2013-08-29 2016-05-10 Varian Semiconductor Equipment Associates, Inc. Semiconductor process pumping arrangements

Family Cites Families (8)

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Publication number Priority date Publication date Assignee Title
CH428072A (de) * 1965-11-19 1967-01-15 Bbc Brown Boveri & Cie Einrichtung an Verdichtern zur Verhinderung des Pumpens
DE2526164A1 (de) * 1975-06-12 1976-12-30 Leybold Heraeus Gmbh & Co Kg Turbomolekularvakuumpumpe mit zumindest teilweise glockenfoermig ausgebildetem rotor
DE2821052C2 (de) * 1978-05-13 1986-08-21 Robert Bosch Gmbh, 7000 Stuttgart Dosier- und Abfüllvorrichtung für flüssige Medien
JPS62153597A (ja) * 1985-12-27 1987-07-08 Hitachi Ltd 真空ポンプ
DE3705912A1 (de) * 1987-02-24 1988-09-01 Alcatel Hochvakuumtechnik Gmbh Hochvakuumpumpe mit einem glockenfoermigen rotor
DE3722164C2 (de) * 1987-07-04 1995-04-20 Balzers Pfeiffer Gmbh Turbomolekularpumpe
DE3826710A1 (de) * 1987-08-07 1989-02-16 Japan Atomic Energy Res Inst Vakuumpumpe
JPS6456987A (en) * 1987-08-26 1989-03-03 Hitachi Ltd Turbo-vacuum pump

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19804768B4 (de) * 1998-02-06 2006-08-24 Pfeiffer Vacuum Gmbh Rotorlagerung für eine Gasreibungspumpe

Also Published As

Publication number Publication date
US5051060A (en) 1991-09-24
JPH0357898A (ja) 1991-03-13
EP0408792A1 (fr) 1991-01-23
JP2994005B2 (ja) 1999-12-27
DE58905785D1 (de) 1993-11-04

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