EP0931939B1 - Pompe à vide - Google Patents

Pompe à vide Download PDF

Info

Publication number
EP0931939B1
EP0931939B1 EP98111113A EP98111113A EP0931939B1 EP 0931939 B1 EP0931939 B1 EP 0931939B1 EP 98111113 A EP98111113 A EP 98111113A EP 98111113 A EP98111113 A EP 98111113A EP 0931939 B1 EP0931939 B1 EP 0931939B1
Authority
EP
European Patent Office
Prior art keywords
vacuum pump
diaphragm
stages
pump
pumping
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
EP98111113A
Other languages
German (de)
English (en)
Other versions
EP0931939A2 (fr
EP0931939A3 (fr
Inventor
Mauro De Simon
Vincenzo Spaziani
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.)
Varian SpA
Original Assignee
Varian SpA
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 Varian SpA filed Critical Varian SpA
Publication of EP0931939A2 publication Critical patent/EP0931939A2/fr
Publication of EP0931939A3 publication Critical patent/EP0931939A3/fr
Application granted granted Critical
Publication of EP0931939B1 publication Critical patent/EP0931939B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B45/00—Pumps or pumping installations having flexible working members and specially adapted for elastic fluids
    • F04B45/04—Pumps or pumping installations having flexible working members and specially adapted for elastic fluids having plate-like flexible members, e.g. diaphragms
    • F04B45/047—Pumps having electric drive
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B27/00—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders
    • F04B27/04—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F04B27/053—Multi-cylinder pumps specially adapted for elastic fluids and characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with an actuating element at the inner ends of the cylinders
    • 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
    • F04D19/046—Combinations of two or more different types of pumps

Definitions

  • the present invention relates to a vacuum pump.
  • More particularly the invention relates to a vacuum pump for producing high vacuum and ultrahigh vacuum.
  • turbomolecular pumps In the field of vacuum pumps, in order to obtain pressure values lower than 10 -2 Pa it is known the use of mechanical pumps named turbomolecular pumps.
  • turbomolecular pumps are not capable of discharging the sucked gas directly to the atmospheric pressure, typically 105 Pa.
  • the two teamed-up pumps are connected in series by a manifold that communicates the exhaust port of the primary turbomolecular pump with the suction port of the secondary or pre-vacuum pump, while the exhaust port of the secondary pump communicates directly with con the environment surrounding the pumping system for discharging to the atmospheric pressure.
  • the secondary or pre-vacuum pump is operated in advance with respect to the primary pump so as to establish the proper pressure conditions within the manifold coupling the two pumps, and only after reaching such conditions the primary turbomolecular pump is started.
  • both pumps are operated together until they achieve a compression ratio that could not be obtained by separately operating each pump.
  • a pumping system comprising a primary pump and a secondary pump as discussed above is disclosed, for example, in EP-A-0 256 234 and DE-A-4 320 963.
  • the system disclosed in the above EP application provides for teaming up two vacuum pumps coupled to each other by a curved duct that is external to both pumps and communicating the exhaust port of the primary pump with the suction port of the secondary pump.
  • a first object of the present invention is therefore to provide a vacuum pumping system capable of discharging to the atmospheric pressure and that is both compact and easy to be manufactured.
  • This first object of the invention is accomplished through a vacuum pump as recited in claim 1.
  • diaphragm pumps reside in that they are highly compact, do not require lubricant and are quite effective, but on the other hand their average operating life is rather short because of the diaphragm wear that requires a frequent replacement of the diaphragm.
  • a second object of the present invention is therefore to provide a simpler diaphragm replacement in diaphragm pumps used as pre-vacuum pumps of pumping systems for high vacuum and ultrahigh vacuum.
  • This second object of the invention is accomplished through a vacuum pump as claimed in claim 5.
  • a common drawback of the pumping systems further resides in that each pump is driven by a dedicated electric motor and therefore each motor requires a separate power supply which increases the power comsumption.
  • a pumping system adapted for achieving high vacuum conditions and providing for the periodically stopping of the secondary pump is disclosed in EP-A-0 373 975.
  • Such system comprises a gas reservoir chamber disposed between the primary pump and the secondary pump, and a valve for closing the gas passage from said chamber to the secondary pump.
  • the valve When the pressure in the reservoir chamber is lower than a predetermined value, the valve is closed and the secondary pump is stopped thus reducing the electric power consumption.
  • This system is however complicated by the presence of a reservoir chamber for the gas, and is more subject to breaking because of the presence of a stop valve.
  • a third object of the present invention is therefore to solve the problem of easily obtaining a reduction of the power consumption in high vacuum pumping systems.
  • This third object of the invention is achieved through a vacuum pump as claimed in claims 17 to 20.
  • a further advantage of the solution claimed in claims 17 to 20 is that the average life of the diaphragms in the diaphragm pumping stages is considerably increased since these pumping stages are operated at a speed considerably lower than that usually employed in the pumping systems.
  • a vacuum pump 1 for achieving high vacuum and ultrahigh vacuum conditions according to the invention, and comprising a plurality of pumping stages 2 of molecular type and a plurality of pumping stages 3 of diaphragm type.
  • the molecular pumping stages 2 are housed in a first portion 4a of a pump cylindric casing 5, and the diaphragm pumping stages 3 are housed in a second portion 4b of said casing 5.
  • Channel 7 is axially directed with respect to the pump body, and is completely housed inside the wall of the pump casing.
  • the molecular pumping stages 2 are made up through the cooperation of rotor disks 8a provided with blades and smooth rotor disks 8b with respective stator rings 9a and 9b.
  • channels 6a and 6b for pumping the gased sucked through the suction inlet 10 of the pump 1 and discharging them into channel 7.
  • the rotor disks 8a and 8b are integer with a shaft 11 supported by a pair of ball bearings 12a and 12b.
  • a first electric motor 13 that drives into rotation the shaft 11, typically at a speed comprised between 20,000 and 100,000 RPM.
  • the electric motor 13 is fed through an electric supply line 14 from a first electronic control unit 15 of the motor 13, which unit is housed in a space 16 at the opposed end of the pump 1 with respect to the suction inlet 10.
  • a substantially cylindric space 20 of the second casing portion 4b there is housed a plurality of diaphragm pumping stages 3 formed by three elastic diaphragm 40, preferably of VitonTM, radially disposed about a crankshaft 22 and connected to such crankshaft 22 by respective connecting rods 23.
  • each connecting rod 23 is secured to the center of the corresponding diaphragm 40, while the opposed end is fitted with a head member 25 provided with a transverse hole for rotatably coupling the rod to the central tubular portion of the crankshaft 22.
  • the crankshaft 22 further comprises a first end section 26 located towards the suction side of the pump 1 and a second end portion 27 located towards the other end of the pump 1.
  • Fans 29a and 29b provided with blades are fitted to said first and second crankshaft end portions 26 and 27, respectively, forming a forced air cooling unit for cooling the spaces 16 and 20.
  • the space 16 contains a second motor 30 for rotating the crankshaft 22, typically at a speed comprised between 1,000 and 4,000 RPM, and a second elettronic unit 31 for controlling the second electric motor 30.
  • crankshaft 22 is further supported by a bearing 21 and is substantially coaxial with the shaft 11 of the molecular pumping stages.
  • the air in space 16 is sucked by the fans 29a and 29b and discharged through a radial exhaust passage 32 in the wall 28 of the casing 5.
  • a wall 33 is disposed between the fan 29b and the space 16 to separate the space 20 from the space 16, and the second motor 30 as well as the electronic control units 15 and 31 are secured to such wall.
  • the space 16 is further enclosed by a substantially cylindric cover 34 provided with slits 35 for the inlet of the air for cooling the electronic components and the motor housed therein.
  • each of said diaphragms 40 is received in a corresponding pumping chamber 41a, 41b and 41c formed in the wall 28 of the casing 5, and is circumferentially retained within the pumping chamber by a metal ring 42 fixed to the outer edge of the pumping chamber 41a, 41b and 41c by a plurality of screws 43.
  • the diaphragm pumping stages 3 are further connected in series to each other by circumferential channels 44a and 44b formed in the wall 28 of the second portion 4b of the casing 5.
  • Channel 44a communicates the gas exhaust hole or port 45a of the pumping chamber 41a with the gas suction hole or port 46b of the adjacent pumping chamber 41b, and channel 44b communicates the exhaust port 45b of the pumping chamber 41b with the suction port 46c of the adjacent pumping chamber 41c.
  • the pumping chamber 41a is further provided with a suction port 46a that directly opens into the common gas passage 7, while the pumping chamber 46c is provided with an exhaust port 45c that in the illustrated example of Figures 1 and 2 is closed by a plug 47.
  • the cylindric casing 5 is formed by two halves that are secured to each other by screws 61, the joining line between the two halves being indicated by the arrow 60.
  • said casing 5 is provided with an open section substantially shaped like a horseshoe, facilitating the replacement of the diaphragms 40 contained inside the diaphragm pumping stages 3.
  • a vacuum pump 101 for obtaining high vacuum conditions comprises a plurality of pumping stages 102 of molecular type and a plurality of pumping stages 103 of diaphragm type.
  • the molecular pumping stages 102 are housed in a first portion 104a of the pump cylindric casing 105, and the diaphragm pumping stages 103 are housed in a second portion 104b of the pump casing 105, corresponding to the base 150 of the vacuum pump.
  • first portion 104a and the second portion 104b are communicating through a common passage 107 formed in the wall 128 of the cylindric casing 105, and the gases discharged by the molecular pumping stages 102 are sucked by the diaphragm pumping stages 103 through this common passage 107.
  • the molecular pumping stages 102 consist of rotor disks 108a provided with blades and of smooth rotor disks 108b cooperating with respective stator rings 109a and 109b.
  • gas pumping channels 106a and 106b With the gases that are sucked through the suction inlet 110 of the pump 101 and then discharged into channel 107.
  • said rotor disks 108a and 108b are integral with a rotatable shaft that is supported by a pair of bearings, and a first electric motor for driving the pump rotatable shaft is located between such bearings.
  • the first electric motor is fed through an electric supply line from a first electronic control unit 115 housed in a space 116 at the opposed end of the pump 101 with respect to the suction port 110, substantially around the base 150.
  • a pair of diaphragm pumping stages 103 each comprising a diaphragm 140 connected to a crankshaft 122 by respective connecting rods 123 are housed. Moreover such diaphragms 140 substantially lie in a same plane.
  • each connecting rod 123 is secured to the center of the corresponding diaphragm 140, while the opposed end is fitted with a head member 125 provided with a transverse hole for rotatably coupling the rod to the opposed ends 126 and 127 of the crankshaft 122.
  • the crankshaft 122 further comprises a first end section 126 fastened to the rotor of a second electric motor 130 driving the crankshaft 122.
  • a second electronic control unit 131 for the second motor 130 Inside the space 116, in addition to the above mentioned crank mechanism for moving the diaphragms 140a and 140b and to the second motor 130 there are located a second electronic control unit 131 for the second motor 130 and a pair of electric fans 129a and 129b.
  • the air flow generated by the electric fans 129a and 129b further cools the pump base 150 that contains the "hot” components such as the motor and the support bearings of the rotating shaft of the molecular stages.
  • the space 116 is further enclosed by a prismatic container 134 provided with slits 135a and 135b, respectively for the inlet and the outlet of the cooling air sucked by the electric fans 129a and 129b.
  • each of the diaphragms 140 is housed in a corresponding pumping chamber 141a and 141b formed in the base 150.
  • the diaphragms 140 are circumferentially retained inside the corresponding pumping chamber 141a and 141b by a metal ring 142 secured to the outer edge of the pumping chamber by a plurality of screws 143.
  • the diaphragm pumping stages 103 are connected in series to each other by a circumferential channel 144 formed in the base 150 of the casing 105.
  • This channel 144 communicates the exhaust port 145a of the pumping chamber 141a with the suction port 146b of the adjacent pumping chamber 141b.
  • the pumping chamber 141a is further provided with a suction port 146a that directly opens into the gas common passage 107, while the pumping chamber 141b is provided with an exhaust port 145b for evacuating the gases to the outside of the pump through a channel 147 that radiallly extends through the base 150 and terminates with a hole 148.
  • the diaphragm pumping stages are designed and dimensioned so as to meet the proper requirements for the maximum discharge pressure (PMOLmax) of the molecular stages and for the maximum flow (Qmax) needed in the particular use conditions of the vacuum pump.
  • the first condition: C1) PMEMmin ⁇ PMOLmax ensures that the diaphragm stages are capable of creating in the suction channel the maximum pressure that the molecular stages can reach, at least in the absence of gaseous load.
  • the minimum pressure PMEMmin that can be reached without any gas flow is about 1,000 Pa, whereas when using four pumping stages in series it is generally possible to achieve pressures of about 100 Pa.
  • turbomolecular pumping stages equipped with smooth rotor disks it was possible to obtain discharge pressures for the molecular stages in the order of 1,000 Pa thus allowing the use of pre-vacuum pumps of the two-stage diaphragm having a low cost.
  • condition C1 During the time interval when the flow is zero, only condition C1) has to be met for maintaining optimum operating conditions in the pumping system.
  • Fig. 5 is a curve showing the dependence of the minimum pressure PMEMmin that can be achieved through a conventional diaphragm pump, as a function of the rotational speed.
  • the minimum pressure PMEMmin is substantially constant until about 1/5 of the rated rocational speed.
  • the rotational speed of the motor driving the diaphragms is adjusted by modifying the armature voltage of a D.C. motor.
  • the electric motor speed can be changed in any kind of electric motor by using a proper control system.
  • a pressure transducer detects the output pressure of the molecular pumping stages and sets the motor feeding voltage so as to maintain such pressure at a predetermined value lower than the maximum discharge pressure PMOLmax of the molecular stages.
  • Fig. 6 schematically illustrates the system for controlling the rotational speed of the motor in the diaphragm stages of a vacuum pump.
  • reference 201 indicates a vacuum pump according to the invention
  • 202 the molecular pumping stages
  • 203 the diaphragm pumping stages
  • 207 the common passage between the two pumps
  • 211 the rotatable shaft of the molecular stages
  • 213 the motor of the molecular stages
  • 215 the electronic control unit for motor 213, 222 the crankshaft of the diaphragm pumping stages
  • 230 the second pump motor of the diaphragm stages
  • 231 the electronic control unit for the second motor 230
  • 245 the exhaust port for evacuating the gases from the diaphragm pumping stages.
  • Arrows A and B indicate the inlet direction and the outlet direction of the gas flowing into and out from pump 201, respectively.
  • Fig. 6 further shows a pressure transducer 270 connected to the common passage 207 and an operational amplifier 271 to which the signal of the transducer 270 and a signal (input 273) corresponding to the pressure threshold that is to be maintained inside channel 207 are applied.
  • the power W drawn by the motor of the molecular pumping stages is substantially proportional to the output pressure of the molecular stages.
  • the signal from the pressure transducer employed in the illustrated example of Fig. 6 can be replaced by a signal proportional to the current drawn by the motor of the molecular stages, which signal is available at the electronic control unit of said motor.
  • Fig. 8 schematically illustrates this simplified embodiment of the system for regulating the rotational speed of the diaphragm stages motor in a vacuum pump where the signal applied to amplifier 271 is directly obtained from control unit 215.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)

Claims (21)

  1. Pompe à vide (1 ; 101 ; 201), comprenant :
    un boítier de pompe (5 ; 105) ;
    une première pluralité d'étages de pompage (2 ; 102 ; 202) du type moléculaire formée par des disques de rotor (8a, 8b ; 108a, 108b) fixés à un arbre mobile en rotation (11 ; 211) et coopérant avec des anneaux de stator (9a, 9b ; 109a, 109b) logés dans une première partie (4a ; 104a) dudit boítier de pompe (5 ; 105) ;
    une seconde pluralité d'étages de pompage (3 ; 103 ; 203) de type à membrane, logée dans une seconde partie (4b ; 104b) dudit boítier de pompe (5 ; 105) ;
    un premier moteur électrique (13 ; 213) destiné à entraíner ledit arbre mobile en rotation (11 ; 211) des étages moléculaires ;
    un second moteur électrique (30 ; 130 ; 230) destiné à entraíner les membranes (40 ; 140) desdits étages à membrane ; caractérisée par
    ladite première partie de boítier (4a ; 104a) et ladite seconde partie de boítier (4b ; 104b) étant pourvues d'au moins un passage commun intégré (7 ; 107 ; 207) destiné à la circulation du gaz déchargé par lesdits étages de pompage moléculaire (2 ; 102 ; 202) et aspiré par lesdits étages de pompage à membrane (3 ; 103 ; 203).
  2. Pompe à vide selon la revendication 1, caractérisée en ce que ledit passage commun (7 ; 107 ; 207) est dirigé sensiblement axialement par rapport au corps de pompe, et est logé complètement à l'intérieur de la paroi (28 ; 128) dudit boítier de pompe (5 ; 105).
  3. Pompe à vide selon la revendication 1 ou 2, caractérisée en ce qu'un espace sensiblement cylindrique (20) est prévu dans ladite seconde partie de boítier (4b ; 104b) dans le but de loger lesdits étages de pompage à membrane (3 ; 103 ; 203).
  4. Pompe à vide selon la revendication 3, caractérisée en ce que ladite première partie de boítier (4a ; 104a) et ladite seconde partie de boítier (4b ; 104b) sont formées comme deux parties distinctes reliées l'une à l'autre par plusieurs moyens de fixation (28).
  5. Pompe à vide selon la revendication 4, caractérisée en ce que ladite seconde partie de boítier (4b ; 104b), logeant les étages de pompage à membrane (3 ; 103 ; 203), comporte une section ouverte sensiblement en forme de fer à cheval et apte à rendre plus facile le remplacement des membranes (40 ; 140) contenues dans lesdits étages de pompage à membrane (3 ; 103 ; 203).
  6. Pompe à vide selon la revendication 3 ou 4 ou 5, caractérisée en ce que lesdits plusieurs étages de pompage à membrane (3 ; 103 ; 203) sont formés par des membranes élastiques (40 ; 140) logées radialement dans autant de chambres de pompage (41a, 41b, 41c ; 141a, 141b) et en ce que chaque membrane (40 ; 140) est actionnée par une tige de liaison correspondante (23 ; 123) reliée mobile en rotation à un vilebrequin (22 ; 122 ; 222) entraíné par ledit second moteur électrique (30 ; 130 ; 230).
  7. Pompe à vide selon la revendication 6, caractérisée en ce que ledit espace (20) loge en outre une soufflante (29a, 29b) destinée à refroidir lesdits étages de pompage à membrane (3 ; 103 ; 203).
  8. Pompe à vide selon la revendication 7, caractérisée en ce que ladite au moins une soufflante (29a, 29b) est couplée audit vilebrequin (22 ; 122 ; 222).
  9. Pompe à vide selon la revendication 1 ou 2, caractérisée en ce que ladite seconde partie de boítier (4b ; 104b) correspond sensiblement à la base (150) de la pompe à vide logeant ledit premier moteur et les paliers supportant l'arbre des étages de pompage moléculaire (2 ; 102 ; 202).
  10. Pompe à vide selon la revendication 9, caractérisée en ce que lesdits plusieurs étages de pompage à membrane (3 ; 103 ; 203) comprennent au moins deux membranes élastiques sensiblement coplanaires (40 ; 140) disposées dans autant de chambres de pompage (41a, 41b, 41c ; 141a, 141b, 141c), et en ce que chaque membrane (40 ; 140) est actionnée par une tige de liaison correspondante (23 ; 123) couplée mobile en rotation à un vilebrequin (22 ; 122 ; 222) entraíné par ledit second moteur électrique (30 ; 130).
  11. Pompe à vide selon l'une quelconque des revendications des revendications 6 à 8 ou 10, caractérisée en ce que lesdites chambres de pompage (41a, 41b, 41c ; 141a, 141b) des étages de membrane sont raccordées les unes aux autres en série par des canaux de circulation de gaz (44a, 44b ; 144), et en ce que la première desdites chambres de pompage, dans le sens de circulation de gaz, comporte un orifice (46a ; 146a) destiné à l'entrée du gaz provenant dudit passage commun (7 ; 107) et la dernière desdites chambres comporte un orifice de décharge (46c ; 146b) destiné à évacuer le gaz à la pression atmosphérique.
  12. Pompe à vide selon l'une quelconque des revendications 3 à 8, caractérisée en ce que lesdits plusieurs étages de pompage à membrane (3 ; 103 ; 203) comprennent trois étages de pompage à membrane raccordés les uns aux autres en série.
  13. Pompe à vide selon l'une quelconque des revendications 9 ou 10, caractérisée en ce que lesdits plusieurs étages de pompage à membrane (3 ; 103 ; 203) comprennent deux étages de pompage à membrane raccordés l'un à l'autre en série.
  14. Pompe à vide selon l'une quelconque des revendications 3 à 13, caractérisée en ce qu'un espace (16 ; 116) est prévu dans l'extrémité de pompe (1 ; 101 ; 201), opposé par rapport à l'entrée d'aspiration (10 ; 110 ; 210), cet espace logeant ledit second moteur des étages de pompage à membrane et le module de commande électronique (15, 31 ; 115, 131 ; 215, 231) dudit premier moteur (13 ; 213) et dudit second moteur (30 ; 130 ; 230).
  15. Pompe à vide selon la revendication 14, caractérisée en ce que les axes de rotation dudit premier moteur (13 ; 213) et dudit second moteur (30 ; 130 ; 230) sont sensiblement coaxiaux.
  16. Pompe à vide selon la revendication 14, caractérisée en ce que ledit espace (16 ; 116) de l'extrémité de pompe (1 ; 101 ; 201), opposé à l'entrée d'aspiration (10 ; 110 ; 210), est sensiblement défini autour de ladite base (150).
  17. Pompe à vide selon l'une quelconque des revendications précédentes, caractérisée en ce que l'on a prévu un moyen destiné à réduire la vitesse de rotation dudit second moteur (30 ; 130 ; 230) des étages de pompage à membrane (3 ; 103 ; 203) lorsque la pression de sortie desdits étages de pompage moléculaire (2 ; 102 ; 202) est plus basse qu'un seuil prédéterminé.
  18. Pompe à vide selon la revendication 17, caractérisée en ce que ledit moyen de réduction comprend un premier signal proportionnel à la pression dans ledit canal commun (7 ; 107 ; 207), un deuxième signal proportionnel à un seuil de pression prédéterminé inférieur à la pression de décharge maximale PMOLmax des étages moléculaires, et un moyen (271) servant à comparer ledit premier signal avec ledit deuxième signal pour engendrer un troisième signal servant à commander la vitesse de rotation dudit second moteur (30 ; 130 ; 230).
  19. Pompe à vide selon la revendication 18, caractérisée en ce que ledit moyen de comparaison comprend un amplificateur opérationnel (271), et en ce que ledit troisième signal est appliqué audit second module de commande électronique (31 ; 131 ; 231) dudit second moteur électrique (30 ; 130 ; 230).
  20. Pompe à vide selon la revendication 19, caractérisée en ce que ledit premier signal est obtenu à partir d'un transducteur de pression (270) disposé en correspondance avec ledit canal commun (7 ; 107 ; 207).
  21. Pompe à vide selon la revendication 19, caractérisée en ce que ledit premier signal correspond à un signal proportionnel à la puissance tirée par le moteur (13 ; 213) des étages de pompage moléculaire (2 ; 102), ledit signal étant disponible à partir du module de commande électronique (15 ; 115 ; 215) dudit premier moteur électrique (13 ; 213).
EP98111113A 1997-12-24 1998-06-17 Pompe à vide Expired - Lifetime EP0931939B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITTO971139 1997-12-24
IT97TO001139A IT1297347B1 (it) 1997-12-24 1997-12-24 Pompa da vuoto.

Publications (3)

Publication Number Publication Date
EP0931939A2 EP0931939A2 (fr) 1999-07-28
EP0931939A3 EP0931939A3 (fr) 2000-08-30
EP0931939B1 true EP0931939B1 (fr) 2003-06-25

Family

ID=11416233

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98111113A Expired - Lifetime EP0931939B1 (fr) 1997-12-24 1998-06-17 Pompe à vide

Country Status (4)

Country Link
EP (1) EP0931939B1 (fr)
DE (1) DE69815806T2 (fr)
HK (1) HK1021401A1 (fr)
IT (1) IT1297347B1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6248157B1 (en) * 1999-08-20 2001-06-19 Systec Inc. Vacuum degassing
FR2822200B1 (fr) * 2001-03-19 2003-09-26 Cit Alcatel Systeme de pompage pour gaz a faible conductivite thermique
JP4250353B2 (ja) 2001-06-22 2009-04-08 エドワーズ株式会社 真空ポンプ
CN101852199B (zh) * 2009-03-31 2011-11-09 储继国 复合真空泵
JP6009193B2 (ja) * 2012-03-30 2016-10-19 株式会社荏原製作所 真空排気装置
DE102013213257B4 (de) * 2013-07-05 2024-09-19 Pfeiffer Vacuum Gmbh Membranvakuumpumpe mit Gasballastventil und Pumpenanordnung
EP3267040B1 (fr) 2016-07-04 2023-12-20 Pfeiffer Vacuum Gmbh Pompe turbomoléculaire

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0784871B2 (ja) 1986-06-12 1995-09-13 株式会社日立製作所 真空排気装置
DE3826710A1 (de) * 1987-08-07 1989-02-16 Japan Atomic Energy Res Inst Vakuumpumpe
JPH01277698A (ja) * 1988-04-30 1989-11-08 Nippon Ferrofluidics Kk 複合型真空ポンプ
DE3865012D1 (de) * 1988-06-01 1991-10-24 Leybold Ag Pumpsystem fuer ein lecksuchgeraet.
FR2640697B1 (fr) * 1988-12-16 1993-01-08 Cit Alcatel Ensemble de pompage pour l'obtention de vides eleves
FR2656658B1 (fr) * 1989-12-28 1993-01-29 Cit Alcatel Pompe a vide turbomoleculaire mixte, a deux arbres de rotation et a refoulement a la pression atmospherique.
IT1241431B (it) * 1990-03-09 1994-01-17 Varian Spa Pompa turbomolecolare perfezionata.
DE9305554U1 (de) * 1993-04-15 1993-06-17 KNF-Neuberger GmbH, 7800 Freiburg Zweifach-Verdrängerpumpe

Also Published As

Publication number Publication date
EP0931939A2 (fr) 1999-07-28
EP0931939A3 (fr) 2000-08-30
DE69815806D1 (de) 2003-07-31
IT1297347B1 (it) 1999-09-01
DE69815806T2 (de) 2004-05-19
ITTO971139A1 (it) 1999-06-24
HK1021401A1 (en) 2000-06-09

Similar Documents

Publication Publication Date Title
KR100521773B1 (ko) 내부 냉각 기류를 이용하는 모터-구동 원심 에어 컴프레서
IL109967A (en) Compressor
US6409477B1 (en) Vacuum pump
EP0931939B1 (fr) Pompe à vide
US6506031B2 (en) Screw compressor with axial thrust balancing and motor cooling device
US5501583A (en) Turbo vacuum pump
JP2002310092A (ja) 真空ポンプ
US6220824B1 (en) Self-propelled vacuum pump
EP0798463A2 (fr) Pompe à vide à spirales sans lubrification
JP2001090690A (ja) 真空ポンプ
KR100273380B1 (ko) 터보 압축기
KR20050084359A (ko) 진공 펌핑 시스템 및 진공 펌핑 장치 작동 방법
KR100273369B1 (ko) 터보압축기의 구동축 구조
US20240077078A1 (en) Rotary vane vacuum pump with gas ballast assembly
KR100273382B1 (ko) 터보 압축기
KR100320192B1 (ko) 터보 압축기의 가스베어링 구조
KR20010064027A (ko) 터보 압축기의 냉각구조
KR100339545B1 (ko) 터보 압축기
KR100304564B1 (ko) 터보압축기의레이디얼베어링구조
KR100273381B1 (ko) 터보 압축기의 구동축 지지장치
KR100253246B1 (ko) 터보압축기
KR20010017179A (ko) 터보 압축기의 축방향 실링구조
KR100273383B1 (ko) 터보 압축기
JP2023184405A (ja) 個別に制御可能なファンを備える真空ポンプ
JP2001207992A (ja) ターボ形ドライポンプ

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

RIC1 Information provided on ipc code assigned before grant

Free format text: 7F 04D 19/04 A, 7F 04D 25/16 B, 7F 04B 45/047 B, 7F 04B 37/14 B, 7F 04B 27/053 B

17P Request for examination filed

Effective date: 20001012

AKX Designation fees paid

Free format text: DE FR GB IT

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE FR GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69815806

Country of ref document: DE

Date of ref document: 20030731

Kind code of ref document: P

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20040326

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20080626

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20080731

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20080617

Year of fee payment: 11

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20080627

Year of fee payment: 11

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20090617

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20100226

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090617

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20100101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090617