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EP0365695A1 - Pompe à vide à déplacement positif avec deux arbres - Google Patents

Pompe à vide à déplacement positif avec deux arbres Download PDF

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Publication number
EP0365695A1
EP0365695A1 EP88117651A EP88117651A EP0365695A1 EP 0365695 A1 EP0365695 A1 EP 0365695A1 EP 88117651 A EP88117651 A EP 88117651A EP 88117651 A EP88117651 A EP 88117651A EP 0365695 A1 EP0365695 A1 EP 0365695A1
Authority
EP
European Patent Office
Prior art keywords
rotors
pump according
vacuum pump
purge gas
pump
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
EP88117651A
Other languages
German (de)
English (en)
Other versions
EP0365695B1 (fr
Inventor
Hanns-Peter Dr. Berges
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 DE8888117651T priority Critical patent/DE3876243D1/de
Priority to EP88117651A priority patent/EP0365695B1/fr
Priority to JP1275119A priority patent/JPH02153292A/ja
Priority to US07/481,853 priority patent/US5046934A/en
Publication of EP0365695A1 publication Critical patent/EP0365695A1/fr
Application granted granted Critical
Publication of EP0365695B1 publication Critical patent/EP0365695B1/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
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/123—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with radially or approximately radially from the rotor body extending tooth-like elements, co-operating with recesses in the other rotor, e.g. one tooth
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C13/00—Adaptations of machines or pumps for special use, e.g. for extremely high pressures
    • F04C13/005—Removing contaminants, deposits or scale from the pump; Cleaning
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C23/00—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids
    • F04C23/001—Combinations of two or more pumps, each being of rotary-piston or oscillating-piston type, specially adapted for elastic fluids; Pumping installations specially adapted for elastic fluids; Multi-stage pumps specially adapted for elastic fluids of similar working principle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
    • F04C29/0007—Injection of a fluid in the working chamber for sealing, cooling and lubricating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2220/00—Application
    • F04C2220/10—Vacuum
    • F04C2220/12—Dry running
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2280/00—Arrangements for preventing or removing deposits or corrosion
    • F04C2280/02—Preventing solid deposits in pumps, e.g. in vacuum pumps with chemical vapour deposition [CVD] processes

Definitions

  • the invention relates to a twin-shaft vacuum pump with a pair of claw rotors rotating in the suction chamber, which together with the suction chamber wall forms a suction side and a pressure side.
  • a two-shaft vacuum pump of this type is known from EU-A 87107089.
  • the rotors are each equipped with a claw (tooth) and a recess and perform their rotary motion in the scooping chamber in a meshing and contact-free manner.
  • the respective cutouts control the inlet and outlet openings located in the side plates of the scoop chamber.
  • twin-shaft vacuum pumps of the type described are therefore often used to evacuate vacuum chambers in which etching, coating or other vacuum treatment or manufacturing processes are carried out. In such operations there is a risk that solids get into the pump, and although also indirectly, that is to say that solid particles only form during the compression of the gases, that is to say during the passage of the gases to be discharged through the vacuum pump. Examples include the formation of aluminum chloride in aluminum etching, ammonium chloride in coating processes, etc.
  • Solid particles that get directly or indirectly into the vacuum pump are deposited in the scooping chamber, including on the peripheral surfaces of the rotors, where they initially narrow the gap between the rotors. Further deposits cause the rotors to touch, which causes the solid particles to roll onto the rotor surfaces. If the deposits continue to increase, the rolled-on layer is thickened, so that a force is generated which forces the rotors and thus the rotor shafts apart. This leads to bearing damage and thus to the failure of the pump, particularly if the rolled layer continues to grow.
  • the present invention has for its object to prevent in a twin-shaft vacuum pump of the type mentioned that solid particles entering the vacuum pump accumulate in the scoop.
  • this object is achieved in that a purge gas line opens on the pressure side into the scoop. If a flushing gas is supplied via this flushing gas line during operation of the pump, gas vortices arising in the scooping chamber prevent the deposition of solid particles entering the scooping chamber.
  • the amount of purge gas supplied does not have to be very high, since otherwise the final pressure of the pump would be unnecessarily deteriorated. It is particularly advantageous if the purge gas at high speed, for. B. is supplied via a nozzle. The solid particles suspended as a result of the resulting vortices can then be conveyed to the next pump stage or to the pump outlet.
  • the purge gas line is expediently located in the immediate vicinity of the gap seal of the two rotors. As a result, the particularly endangered peripheral surfaces of the two rotors are kept free of deposits.
  • the exemplary embodiment shown in FIG. 1 is a three-stage vacuum pump 1 with two shafts 2 and 3 and three pairs of rotors 4, 5 or 6, 7 or 8, 9.
  • the axial length of the rotors decreases from the suction side to the pressure side .
  • the rotary pistons are of the claw type (see FIG. 2) and rotate in the scoops 11, 12, 13, which are formed by the shields 14 to 17 and the housing rings 18 to 20.
  • the drive motor 22 is located next to the vertically arranged pump housing. Below the lower bearing plate 17, the shafts 2, 3 are equipped with gear wheels 23, 24 of the same diameter, which are used to synchronize the movement of the rotor pairs 4, 5 or 6, 7 or 8, 9 serve.
  • the drive motor 22 also has a gearwheel 25 on its underside. The drive connection is established by a further gearwheel 26 which is in engagement with the gearwheels 24 and 25.
  • the shafts 2, 3 are supported by roller bearings 27.
  • the upper end plate 14 is equipped with a horizontally arranged connecting flange 28, which forms the inlet 29 of the pump.
  • the inlet channel 31 opens at the end (opening 32) into the scoop chamber 11 of the first stage.
  • the one on the front The outlet opening of the first stage is designated 33 and leads into the connecting channel 34.
  • the connecting channel 34 located in the shield 15 is connected to the inlet opening 35 of the second stage.
  • the end shield 16 is designed accordingly.
  • Below the lowermost (third) pump stage is the outlet 36, which is connected to the front outlet opening 37 in the lower bearing plate 17.
  • Figure 2 shows the contour of the rotors. They each have a claw 41, 42 and a recess 43, 44 and carry out their rotary movement according to the arrows 45 in a meshing and contactless manner.
  • the gap seal located between the two rotors is designated by 46.
  • the control of the inlet opening 32, 35 and the outlet opening 33, 37 takes place via the respective recess 43, 44.
  • the rotors form two spaces 47 and 48, of which the enlarging space 47 is connected to the inlet opening 32, 35 .
  • the space 47 therefore forms the suction side.
  • the shrinking space 48 is connected to the outlet 33, 37 after a slight rotational movement. The space 48 thus forms the pressure side.
  • the mouth 49 of a purge gas line (not shown in FIG. 2) is located on the pressure side 48.
  • the mouth 49 is located in the immediate vicinity of the sealing gap 46 between the two rotors, so that this sealing gap is preferably kept free of solid particles.
  • Figure 1 shows that the scoops 11, 12, 13 are assigned a plurality of mouths 49.
  • the scooping chamber 12 there are, for example, two openings 49, directly opposite one another in the respective side plates 15, 16.
  • the desired effect of keeping solid particles in suspension is achieved in a particularly favorable manner.
  • the orifices 49 are connected to a purge gas source 51, specifically via bores 52, 53 in the side plates 15, 16 and via the line system 54 provided outside the pump with the valve 55.
  • Nozzles are located in the bores 52, 53, which are only shown schematically 56, 57, which serve on the one hand to reduce the amount of gas supplied and on the other hand to increase the speed of the gas.
  • a suitable purge gas is nitrogen, for example.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Reciprocating Pumps (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
EP88117651A 1988-10-24 1988-10-24 Pompe à vide à déplacement positif avec deux arbres Expired - Lifetime EP0365695B1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DE8888117651T DE3876243D1 (de) 1988-10-24 1988-10-24 Zweiwellenvakuumpumpe mit schoepfraum.
EP88117651A EP0365695B1 (fr) 1988-10-24 1988-10-24 Pompe à vide à déplacement positif avec deux arbres
JP1275119A JPH02153292A (ja) 1988-10-24 1989-10-24 吸入室を備えた２軸式真空ポンプ
US07/481,853 US5046934A (en) 1988-10-24 1990-02-20 Twin shaft vacuum pump with purge gas inlet

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP88117651A EP0365695B1 (fr) 1988-10-24 1988-10-24 Pompe à vide à déplacement positif avec deux arbres

Publications (2)

Publication Number Publication Date
EP0365695A1 true EP0365695A1 (fr) 1990-05-02
EP0365695B1 EP0365695B1 (fr) 1992-11-25

Family

ID=8199481

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88117651A Expired - Lifetime EP0365695B1 (fr) 1988-10-24 1988-10-24 Pompe à vide à déplacement positif avec deux arbres

Country Status (4)

Country Link
US (1) US5046934A (fr)
EP (1) EP0365695B1 (fr)
JP (1) JPH02153292A (fr)
DE (1) DE3876243D1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2670839A1 (fr) * 1990-12-21 1992-06-26 Cit Alcatel Machine, telle que pompe a vide ou compresseur du type volumetrique ou a entrainement.
WO1992015786A1 (fr) * 1991-03-04 1992-09-17 Leybold Aktiengesellschaft Systeme pour l'alimentation en gaz inerte d'une pompe a vide a etages multiples fonctionnant a sec
DE4233142A1 (de) * 1992-10-02 1994-04-07 Leybold Ag Verfahren zum Betrieb einer Klauenvakuumpumpe und für die Durchführung dieses Betriebsverfahrens geeignete Klauenvakuumpumpe
WO1994009275A1 (fr) * 1992-10-12 1994-04-28 Leybold Aktiengesellschaft Procede pour faire fonctionner une pompe a vide a compression a sec
DE19629174A1 (de) * 1996-07-19 1998-01-22 Leybold Vakuum Gmbh Klauenvakuumpumpe
WO2007036689A1 (fr) * 2005-09-28 2007-04-05 Edwards Limited Procede de pompage de gaz
GB2440341A (en) * 2006-07-24 2008-01-30 Boc Group Plc Vacuum pump with purge gas channel
WO2008129317A1 (fr) * 2007-04-23 2008-10-30 Edwards Limited Pompe à vide
EP1990543A1 (fr) * 2007-05-11 2008-11-12 Alcatel Lucent Pompe à vide sèche
CN102762867A (zh) * 2009-12-24 2012-10-31 爱德华兹有限公司 具有吹扫气体系统的干式真空泵和吹扫方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9708397D0 (en) * 1997-04-25 1997-06-18 Boc Group Plc Improvements in vacuum pumps
JP2001304115A (ja) * 2000-04-26 2001-10-31 Toyota Industries Corp 真空ポンプにおけるガス供給装置
EP1552152B1 (fr) * 2002-10-14 2013-03-20 Edwards Limited Pompe a vide a piston rotatif pourvue d'un equipement de lavage
DE102010055798A1 (de) * 2010-08-26 2012-03-01 Vacuubrand Gmbh + Co Kg Vakuumpumpe
JP6025876B2 (ja) * 2012-03-02 2016-11-16 ドーヴァー パンプ ソリューションズ グループ（ヨーロッパ）ゲーエムベーハーＤｏｖｅｒ Ｐｕｍｐ Ｓｏｌｕｔｉｏｎｓ Ｇｒｏｕｐ （Ｅｕｒｏｐｅ） Ｇｍｂｈ 密閉機構、密閉機構を有する搬送装置、および密閉機構を操作する方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1834976A (en) * 1928-03-09 1931-12-08 Patiag Patentverwertungs Und I Rotary compressor, pump or the like
FR2109798A5 (fr) * 1970-10-01 1972-05-26 Atlas Copco Ab
US4621985A (en) * 1984-05-30 1986-11-11 Honjo Chemical Kabushiki Kaisha High vacuum apparatus
EP0290662A1 (fr) * 1987-05-15 1988-11-17 Leybold Aktiengesellschaft Pompe à vide à déplacement positif avec deux arbres

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2111126A (en) * 1981-12-09 1983-06-29 British Oxygen Co Ltd Rotary positive-displacement fluid-machines
NL180992C (nl) * 1984-12-07 1987-06-01 Naaktgeboren Maschf Rotterdam Tankwagen.
GB8809621D0 (en) * 1988-04-22 1988-05-25 Boc Group Plc Dry pump with closed loop filter

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1834976A (en) * 1928-03-09 1931-12-08 Patiag Patentverwertungs Und I Rotary compressor, pump or the like
FR2109798A5 (fr) * 1970-10-01 1972-05-26 Atlas Copco Ab
US4621985A (en) * 1984-05-30 1986-11-11 Honjo Chemical Kabushiki Kaisha High vacuum apparatus
EP0290662A1 (fr) * 1987-05-15 1988-11-17 Leybold Aktiengesellschaft Pompe à vide à déplacement positif avec deux arbres

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2670839A1 (fr) * 1990-12-21 1992-06-26 Cit Alcatel Machine, telle que pompe a vide ou compresseur du type volumetrique ou a entrainement.
EP0492332A1 (fr) * 1990-12-21 1992-07-01 Alcatel Cit Pompe à vide avec injection de gaz sec
US5234323A (en) * 1990-12-21 1993-08-10 Alcatel Cit Fluid positive displacement machine with gas injection in the discharge region
WO1992015786A1 (fr) * 1991-03-04 1992-09-17 Leybold Aktiengesellschaft Systeme pour l'alimentation en gaz inerte d'une pompe a vide a etages multiples fonctionnant a sec
DE4233142A1 (de) * 1992-10-02 1994-04-07 Leybold Ag Verfahren zum Betrieb einer Klauenvakuumpumpe und für die Durchführung dieses Betriebsverfahrens geeignete Klauenvakuumpumpe
WO1994008141A1 (fr) * 1992-10-02 1994-04-14 Leybold Aktiengesellschaft Procede pour l'utilisation d'une pompe a vide a griffes et pompe a vide a griffes propre a l'application de ce procede
US5660535A (en) * 1992-10-02 1997-08-26 Leybold Aktiengesellschaft Method of operating a claw-type vacuum pump and a claw-type vacuum pump suitable for carrying out the method
WO1994009275A1 (fr) * 1992-10-12 1994-04-28 Leybold Aktiengesellschaft Procede pour faire fonctionner une pompe a vide a compression a sec
US5975857A (en) * 1992-10-12 1999-11-02 Leybold Aktiengesellschaft Process for operating a dry-compression vacuum pump as well as a suitable vacuum pump for implementation of this process
DE19629174A1 (de) * 1996-07-19 1998-01-22 Leybold Vakuum Gmbh Klauenvakuumpumpe
WO2007036689A1 (fr) * 2005-09-28 2007-04-05 Edwards Limited Procede de pompage de gaz
GB2440341A (en) * 2006-07-24 2008-01-30 Boc Group Plc Vacuum pump with purge gas channel
GB2440341B (en) * 2006-07-24 2011-09-21 Boc Group Plc Vacuum pump
WO2008129317A1 (fr) * 2007-04-23 2008-10-30 Edwards Limited Pompe à vide
US9004891B2 (en) 2007-04-23 2015-04-14 Edwards Limited Vacuum pump
EP1990543A1 (fr) * 2007-05-11 2008-11-12 Alcatel Lucent Pompe à vide sèche
FR2916022A1 (fr) * 2007-05-11 2008-11-14 Alcatel Lucent Sas Pompe a vide seche
CN102762867A (zh) * 2009-12-24 2012-10-31 爱德华兹有限公司 具有吹扫气体系统的干式真空泵和吹扫方法
CN102762867B (zh) * 2009-12-24 2015-12-09 爱德华兹有限公司 具有吹扫气体系统的干式真空泵和吹扫方法
US9334863B2 (en) 2009-12-24 2016-05-10 Edwards Limited Pump

Also Published As

Publication number Publication date
DE3876243D1 (de) 1993-01-07
JPH02153292A (ja) 1990-06-12
EP0365695B1 (fr) 1992-11-25
US5046934A (en) 1991-09-10

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