EP0290663A1 - Pompe à vide à deux arbres, mono-ou polyétagée - Google Patents

Pompe à vide à deux arbres, mono-ou polyétagée Download PDF

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Publication number
EP0290663A1
EP0290663A1 EP87107090A EP87107090A EP0290663A1 EP 0290663 A1 EP0290663 A1 EP 0290663A1 EP 87107090 A EP87107090 A EP 87107090A EP 87107090 A EP87107090 A EP 87107090A EP 0290663 A1 EP0290663 A1 EP 0290663A1
Authority
EP
European Patent Office
Prior art keywords
pump according
pump
expansion
cooling
shafts
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
EP87107090A
Other languages
German (de)
English (en)
Other versions
EP0290663B1 (fr
Inventor
Ralf Steffens
Hans-Peter Dr. Kabelitz
Hanns-Peter Dr. Berges
Hartmut Kriehn
Wolfgang Leier
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 EP87107090A priority Critical patent/EP0290663B1/fr
Priority to DE8787107090T priority patent/DE3786917D1/de
Priority to US07/192,559 priority patent/US4983107A/en
Priority to JP63115016A priority patent/JP2650041B2/ja
Publication of EP0290663A1 publication Critical patent/EP0290663A1/fr
Application granted granted Critical
Publication of EP0290663B1 publication Critical patent/EP0290663B1/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
    • F04C18/082—Details specially related to intermeshing engagement type pumps
    • 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
    • F04C29/04—Heating; Cooling; Heat insulation

Definitions

  • the invention relates to a twin-shaft vacuum pump with a pumping chamber, with a pair of rotary pistons located in the pumping chamber, with shields that laterally delimit the pumping chamber, and with a housing ring that peripherally delimits the pumping chamber.
  • Two-shaft pumps are e.g. B. Root pumps, whose rotary lobes are approximately 8-shaped in section, Northey pumps with claw rotors, screw pumps and the like.
  • the pairs of rotary lobes rotate in a contact-free manner with respect to one another and to the walls of the pump chamber and cause the pumping medium to be conveyed from the inlet to the pump outlet.
  • the two-shaft pumps mentioned are particularly suitable for use as vacuum pumps, since there is no need for sealants and coolants in the pumping chamber, so there is no risk of contamination due to the sealant.
  • the volumetric efficiency of twin-shaft pumps of this type is therefore defined by the ratio of the amount of gas actually pumped to the theoretically pumpable amount of gas.
  • the selection of any small games is not possible due to thermal reasons.
  • the pump heats up during operation. There is a reduction in the existing games, so that there is a risk of the pistons starting up on the housing. With an increase in Speeds that are desired to reduce the construction volume increase these difficulties due to the increased power density.
  • the housing there is the option of dissipating the heat by water or air cooling.
  • the heat from the rotating pistons is essentially dissipated only by the medium itself, which either transfers the heat of the piston to the housing or removes it itself. Since only a few molecules are available to dissipate the heat when the twin-shaft pumps are operated in a vacuum, the thermal problems in this area of application are particularly critical.
  • the present invention has for its object to reduce the adverse effects of thermal expansion occurring in twin-shaft vacuum pumps of the type mentioned.
  • this object is achieved in that the housing ring and the rotary pistons consist of different materials and that the coefficient of expansion of the piston material is smaller than the coefficient of expansion of the housing material.
  • the pistons are made of gray cast iron or ceramic and the associated housing ring is made of aluminum, the less warming housing can follow the expansion of the more warming rotors, since aluminum has a much larger expansion coefficient than gray cast iron or ceramic.
  • the pump is equipped with claw-type rotors, it is sufficient if the claws of these rotors are made of ceramic, for example, in order to delay radial play or prevent them from occurring.
  • a rotor of this type is less expensive to manufacture than a rotor made entirely of ceramic.
  • bushings are arranged on the shafts for fixing the position of the rotors, which consist of a material whose coefficient of expansion is smaller than the coefficient of expansion of the rotor material. This measure is particularly advantageous for multi-stage pumps.
  • a further advantageous measure consists in cooling the outer side shields, but not the housing ring (s) and the intermediate shields present in multi-stage pumps. This keeps the bearing temperature low and reduces the rotor temperature somewhat, while the housing temperature takes on higher values. This enables the housing to take part in the expansion movements of the rotors, which heat up more strongly (to "breathe”). This applies in particular if the pump housing is encapsulated and the heat emission is further reduced.
  • the temperature of the rotors can be further reduced if they are equipped with cooling.
  • 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 shafts 2, 3 are arranged vertically. This also applies to the drive motor, not shown, which is arranged next to the pump housing. Below the lower bearing plate 17, the shafts 2, 3 are equipped with gear wheels 23, 24 of the same diameter, which serve to synchronize the movement of the rotor pairs 4, 5 or 6, 7 or 8, 9.
  • the drive motor also has a gear on its underside. The drive connection is established by a further gear 26, which is in engagement with the gear of the drive motor and the gear 24 of the synchronization gear.
  • 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 end opening of the first stage is designated 33 and leads into the connecting duct 34.
  • the connecting duct 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.
  • An oil-containing space 40 formed by a common shaft trough 41, is provided below the system consisting of the pump housing and motor.
  • An oil pump 42 connected to the shaft 2 protrudes into this shaft trough 41.
  • Lubricant channels not shown in detail, extend from the oil pump to the points of the pump (bearings, engagements of the gear wheels 23 to 26, oil seals or the like) which require oil lubrication .
  • cooling water channels 43 and 44 are provided in the side plates 14 and 17. Cooling water inlet and outlet are labeled 45 and 46 (upper plate 14) and 47 and 48 (lower plate 17).
  • a cooling water drain 49 is arranged at the lowest point of the channel system 44, so that a simple cooling water drain is possible and complete emptying is ensured.
  • the rotors 4 to 9 are pushed onto and held on the shafts 2, 3 in such a way that their positions are not influenced by a longitudinal play of the shafts. Torque transmission must be possible without play.
  • the upper bearings 27 are designed as roller or needle bearings, which form a longitudinal expansion play of the shafts.
  • pairs of bushings 51 to 53 are provided, which are located at the level of the intermediate shields 15, 16 and in the lower end shield 17.
  • the packages consisting of bushings and rotors are spring-loaded on the shafts with the help of disc springs 54, 55 and nuts 56, 57.
  • the material of the bushings is steel or ceramic and therefore has a smaller coefficient of expansion than pistons made of gray cast iron, for example.
  • Thermal operational safety is further improved if the side shields 14, 17 are cooled, but the housing rings 18 to 20 and the intermediate shields 15, 16 are not. An effective movement of the housing and the intermediate shields is thereby achieved. Storage temperatures can be kept low. In addition, piston cooling is associated with this to a small extent.
  • the side shields 14, 17 are flowed through essentially horizontally.
  • the cooling water outlet 46 of the upper plate 14 is connected to the cooling water inlet 47 of the lower plate 17 and the outlet 48 of the lower plate 17 to the inlet 45 of the upper plate 14 by two connecting lines 58 and 59.
  • a closed cooling circuit is formed, in which a circuit of the cooling medium occurs only by conventional means. This convection flow is increased when the cooling water inlet 45, 47 is respectively lower than the cooling water outlet 46, 48.
  • a fresh water supply line 61 with a valve 62 is connected to the line 59.
  • the valve opens when the temperature of the cooling medium exceeds a specified value (measuring point 63).
  • the cold cooling medium supplied initially mixes with the existing warm coolant, so that the pump is not subjected to a cold shock.
  • a container 64 is connected to the line 58, which receives excess cooling water and serves as an expansion vessel.
  • Fig. 3 shows a piston 4 to 9 of the claw type.
  • the central section 65 and the claw 66 are separate components, each with a flat surface. The two parts are screwed together (screw connection 67) in such a way that the flat surfaces lie against one another.
  • the central body 65 is made of gray cast iron, for example, while the claw 66 is made of ceramic. When a piston of this type is heated, the axial expansion is reduced.
  • FIGS. 1 and 4 show a single-stage, likewise vertically arranged two-shaft vacuum pump 1.
  • Parts of the exemplary embodiments according to FIGS. 1 and 4 which correspond to one another are provided with the same reference numerals.
  • To reduce excessive heating and thus expansion of the pistons 4, 5, these are equipped with cooling.
  • the shafts 2, 3 are extended downward and passed through the oil space 40 and the oil pan 41.
  • the radial shaft sealing rings 71, 72 serve to seal the shafts 2, 3 in the oil pan.
  • the shafts 2, 3 are each provided with a blind hole 73, 74 which is open at the bottom. With their lower ends, the shafts 2, 3 protrude into a coolant tank 75, which is arranged below the oil space 40. Coolant supply lines 76, 77 protrude into the blind bores 73, 74 from below and extend with open ends to approximately the center of the rotors 4, 5.
  • the coolant supply lines 76, 77 are connected to a feed pump 78, the inlet side of which is connected to the coolant tank 75 via the line 79.
  • a heat exchanger 81 is expediently switched on in line 79 so that a sufficiently low temperature of the coolant is ensured.
  • the coolant is injected into the blind bores 73, 74 and flows back into the coolant tank 75 due to gravity. From there it passes through line 79 and the heat exchanger back to the feed pump 78.
  • Water is expediently considered as a coolant. Oil or compressed air can also be used. If oil is used for lubricating the bearings and / or gearwheels at the same time, separate oil and coolant containers 40 and 75 can be dispensed with, so that seals 71 and 72 can also be dispensed with.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Non-Positive Displacement Air Blowers (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
EP87107090A 1987-05-15 1987-05-15 Pompe à vide à deux arbres, mono-ou polyétagée Expired - Lifetime EP0290663B1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP87107090A EP0290663B1 (fr) 1987-05-15 1987-05-15 Pompe à vide à deux arbres, mono-ou polyétagée
DE8787107090T DE3786917D1 (de) 1987-05-15 1987-05-15 Ein- oder mehrstufige zweiwellenvakuumpumpe.
US07/192,559 US4983107A (en) 1987-05-15 1988-05-11 Multistage rotary piston vacuum pump having sleeves to fix shaft positions
JP63115016A JP2650041B2 (ja) 1987-05-15 1988-05-13 ２軸真空ポンプ

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP87107090A EP0290663B1 (fr) 1987-05-15 1987-05-15 Pompe à vide à deux arbres, mono-ou polyétagée

Publications (2)

Publication Number Publication Date
EP0290663A1 true EP0290663A1 (fr) 1988-11-17
EP0290663B1 EP0290663B1 (fr) 1993-08-04

Family

ID=8196997

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87107090A Expired - Lifetime EP0290663B1 (fr) 1987-05-15 1987-05-15 Pompe à vide à deux arbres, mono-ou polyétagée

Country Status (4)

Country Link
US (1) US4983107A (fr)
EP (1) EP0290663B1 (fr)
JP (1) JP2650041B2 (fr)
DE (1) DE3786917D1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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
WO2001048383A1 (fr) * 1999-12-27 2001-07-05 Leybold Vakuum Gmbh Pompe a vide a vis refroidie
WO2001048385A1 (fr) * 1999-12-27 2001-07-05 Leybold Vakuum Gmbh Pompe a vide a vis pourvue d'un circuit de refrigerant
DE10040482A1 (de) * 2000-08-18 2002-02-28 Univ Ilmenau Tech Zweiwellenklauenpumpe
EP2902629A1 (fr) * 2014-01-30 2015-08-05 Pfeiffer Vacuum GmbH Pompe à vide avec réfrigérateur de lubrifiant
CN111594439A (zh) * 2020-04-23 2020-08-28 浙江佳成机械有限公司 一种三级螺杆压缩机

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992014060A1 (fr) * 1991-02-01 1992-08-20 Leybold Aktiengesellschaft Pompe a vide du type a marche a sec avec deux arbres
EP0497995A1 (fr) * 1991-02-01 1992-08-12 Leybold Aktiengesellschaft Pompe sèche à vide
GB9604486D0 (en) * 1996-03-01 1996-05-01 Boc Group Plc Improvements in vacuum pumps
DE19736017A1 (de) * 1997-08-20 1999-02-25 Peter Frieden Trockenverdichtende Vakuumpumpe oder Kompressor
DE19820523A1 (de) * 1998-05-08 1999-11-11 Peter Frieden Schraubenspindel-Vakuumpumpe mit Rotorkühlung
US7077159B1 (en) * 1998-12-23 2006-07-18 Applied Materials, Inc. Processing apparatus having integrated pumping system
JP3673743B2 (ja) * 2001-09-27 2005-07-20 大晃機械工業株式会社 スクリュー式真空ポンプ
GB0223769D0 (en) * 2002-10-14 2002-11-20 Boc Group Plc A pump
GB2426036A (en) * 2005-05-10 2006-11-15 Bernard Whicher Vertical Northey compressor
WO2018132019A2 (fr) * 2017-01-10 2018-07-19 John Fleming Améliorations apportées à des pompes à griffes rotatives
JP7008955B1 (ja) * 2021-07-16 2022-01-25 オリオン機械株式会社 クローポンプ

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB525761A (en) * 1939-02-28 1940-09-04 Milo Ab Improvements in or relating to rotary compressors
GB529059A (en) * 1939-05-11 1940-11-13 James Pontus Johnson Improvements in or relating to air pumps
DE758120C (de) * 1939-03-19 1953-10-05 Bosch Gmbh Robert Drehkolbengeblaese
CH365821A (de) * 1959-03-17 1962-11-30 Balzers Hochvakuum Verfahren zum Betrieb von mechanischen Vakuumpumpen und Vakuumpumpe zur Durchführung dieses Verfahrens
US3150593A (en) * 1961-04-24 1964-09-29 Waukesha Foundry Co Metering pump
US3237276A (en) * 1962-05-04 1966-03-01 Ohe Ernst Von Der Cylindrical rotor assembly
DE2007880A1 (de) * 1970-02-20 1971-09-02 Brown, Arthur Corning N Y (VStA) Rotationsverdrangungsmaschine
DE3124247C1 (de) * 1981-06-19 1983-06-01 Boge Kompressoren Otto Boge Gmbh & Co Kg, 4800 Bielefeld Schraubenverdichter
GB2141486A (en) * 1983-06-16 1984-12-19 Pfeiffer Vakuumtechnik Rotary pump

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Publication number Priority date Publication date Assignee Title
US901539A (en) * 1905-06-14 1908-10-20 John George Leyner Multiple-stage air-compressor.
US1653814A (en) * 1926-01-02 1927-12-27 William E Mild Rotary compressor
US2014932A (en) * 1933-03-17 1935-09-17 Gen Motors Corp Roots blower
US2367463A (en) * 1939-03-18 1945-01-16 Heimbach Bruno Rotary blower
US2708548A (en) * 1953-10-12 1955-05-17 Hosdreg Company Inc Blower
US2938664A (en) * 1955-01-17 1960-05-31 Leybold S Nachfolger Fa E Pump
JPS4857706U (fr) * 1971-10-29 1973-07-23
US4035112A (en) * 1974-02-20 1977-07-12 Outboard Marine Corporation Rotary engine cooling and exhaust system
FR2389784B1 (fr) * 1977-05-06 1984-02-24 Siebec Filtres
GB2088957B (en) * 1980-12-05 1984-12-12 Boc Ltd Rotary positive-displacement fluidmachines
JPS58160585A (ja) * 1982-03-19 1983-09-24 Hitachi Ltd スクリユ−ロ−タ
US4504201A (en) * 1982-11-22 1985-03-12 The Boc Group Plc Mechanical pumps
IT1179911B (it) * 1984-04-16 1987-09-16 Gilardini Spa Compressore volumetrico per l alimentazione a motori endotermici di veicoli
JPS61152991A (ja) * 1984-12-26 1986-07-11 Hitachi Ltd スクリユ−流体機械
DE3545821A1 (de) * 1985-12-23 1987-07-02 Wankel Gmbh Fluessigkeitsgekuehltes gehaeuse einer rotationskolbenbrennkraftmaschine

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB525761A (en) * 1939-02-28 1940-09-04 Milo Ab Improvements in or relating to rotary compressors
DE758120C (de) * 1939-03-19 1953-10-05 Bosch Gmbh Robert Drehkolbengeblaese
GB529059A (en) * 1939-05-11 1940-11-13 James Pontus Johnson Improvements in or relating to air pumps
CH365821A (de) * 1959-03-17 1962-11-30 Balzers Hochvakuum Verfahren zum Betrieb von mechanischen Vakuumpumpen und Vakuumpumpe zur Durchführung dieses Verfahrens
US3150593A (en) * 1961-04-24 1964-09-29 Waukesha Foundry Co Metering pump
US3237276A (en) * 1962-05-04 1966-03-01 Ohe Ernst Von Der Cylindrical rotor assembly
DE2007880A1 (de) * 1970-02-20 1971-09-02 Brown, Arthur Corning N Y (VStA) Rotationsverdrangungsmaschine
DE3124247C1 (de) * 1981-06-19 1983-06-01 Boge Kompressoren Otto Boge Gmbh & Co Kg, 4800 Bielefeld Schraubenverdichter
GB2141486A (en) * 1983-06-16 1984-12-19 Pfeiffer Vakuumtechnik Rotary pump

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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
WO2001048383A1 (fr) * 1999-12-27 2001-07-05 Leybold Vakuum Gmbh Pompe a vide a vis refroidie
WO2001048385A1 (fr) * 1999-12-27 2001-07-05 Leybold Vakuum Gmbh Pompe a vide a vis pourvue d'un circuit de refrigerant
US6758660B2 (en) 1999-12-27 2004-07-06 Leybold Vakuum Gmbh Screw vacuum pump with a coolant circuit
DE10040482A1 (de) * 2000-08-18 2002-02-28 Univ Ilmenau Tech Zweiwellenklauenpumpe
EP2902629A1 (fr) * 2014-01-30 2015-08-05 Pfeiffer Vacuum GmbH Pompe à vide avec réfrigérateur de lubrifiant
CN111594439A (zh) * 2020-04-23 2020-08-28 浙江佳成机械有限公司 一种三级螺杆压缩机

Also Published As

Publication number Publication date
DE3786917D1 (de) 1993-09-09
JPS63302193A (ja) 1988-12-09
JP2650041B2 (ja) 1997-09-03
EP0290663B1 (fr) 1993-08-04
US4983107A (en) 1991-01-08

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