EP3201469B1 - Pumping system for generating a vacuum and method for pumping by means of this pumping system - Google Patents

Pumping system for generating a vacuum and method for pumping by means of this pumping system Download PDF

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Publication number
EP3201469B1
EP3201469B1 EP14781160.8A EP14781160A EP3201469B1 EP 3201469 B1 EP3201469 B1 EP 3201469B1 EP 14781160 A EP14781160 A EP 14781160A EP 3201469 B1 EP3201469 B1 EP 3201469B1
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EP
European Patent Office
Prior art keywords
vacuum pump
pump
pumping system
main
auxiliary
Prior art date
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Revoked
Application number
EP14781160.8A
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German (de)
French (fr)
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EP3201469A1 (en
Inventor
Didier MÜLLER
Jean-Eric Larcher
Théodore ILTCHEV
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Ateliers Busch SA
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Ateliers Busch SA
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Application filed by Ateliers Busch SA filed Critical Ateliers Busch SA
Priority to PT147811608T priority Critical patent/PT3201469T/en
Priority to PL14781160T priority patent/PL3201469T3/en
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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
    • F04C25/00—Adaptations of pumps for special use of pumps for elastic fluids
    • F04C25/02—Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
    • 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
    • F04B37/00—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00
    • F04B37/10—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use
    • F04B37/14—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use to obtain high vacuum
    • 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
    • F04B41/00—Pumping installations or systems specially adapted for elastic fluids
    • F04B41/06—Combinations of two or more pumps
    • 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
    • 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
    • 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
    • F04C23/005—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 dissimilar 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
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/02—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids specially adapted for several pumps connected in series or in parallel
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04F—PUMPING OF FLUID BY DIRECT CONTACT OF ANOTHER FLUID OR BY USING INERTIA OF FLUID TO BE PUMPED; SIPHONS
    • F04F5/00—Jet pumps, i.e. devices in which flow is induced by pressure drop caused by velocity of another fluid flow
    • F04F5/14—Jet pumps, i.e. devices in which flow is induced by pressure drop caused by velocity of another fluid flow the inducing fluid being elastic fluid
    • F04F5/16—Jet pumps, i.e. devices in which flow is induced by pressure drop caused by velocity of another fluid flow the inducing fluid being elastic fluid displacing elastic fluids
    • F04F5/20—Jet pumps, i.e. devices in which flow is induced by pressure drop caused by velocity of another fluid flow the inducing fluid being elastic fluid displacing elastic fluids for evacuating
    • 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
    • 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
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/06—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids specially adapted for stopping, starting, idling or no-load operation

Definitions

  • the present invention relates to the field of vacuum techniques. More specifically, it relates to a pumping system comprising at least one lug pump, as well as a method of pumping by means of this pumping system.
  • the speed of rotation of the pump plays a very important role, by defining the operation of the pump during the various successive phases during the emptying of the vacuum chamber.
  • the electrical power required in the first pumping phases when the suction pressure is between atmospheric pressure and approximately 100 mbar, that is to say during operation at high mass flow, would be very high if the rotation speed of the pump could not be reduced.
  • variable speed drive which allows the speed or consequently the power to be reduced or increased according to different criteria such as pressure, maximum current, torque limit, temperature, etc. But during periods of operation at reduced rotational speed there are drops in flow at high pressure, the flow being proportional to the rotational speed. Also, the variation of speed by frequency converter imposes an additional cost and size.
  • the state of the art concerning vacuum pump systems which aim to improve the final vacuum and increase the flow rate typically includes booster pumps of the Roots type arranged upstream of the main dry pumps.
  • This type of system is bulky, works either with bypass valves presenting reliability problems, or by using means of measurement, control, adjustment or control.
  • these means of control, adjustment or slaving must be actively controlled, which necessarily results in an increase in the number of system components, its complexity and its cost.
  • the patent application US 2003/0068233 A1 offers a vacuum pumping system which includes a main pump, the discharge of which is connected to an exhaust duct provided with a non-return valve. An auxiliary pump is also provided, downstream of the main pump. This auxiliary pump is connected in parallel with the non-return valve.
  • Vacuum pumping systems comprising a main pump and an auxiliary pump connected in parallel with a non-return valve are also known from the documents.
  • WO 2014/012896 A2 JP 2007 100562 A , EP 1,243,795 A1 , DE 88 16 875 U1 and DE 38 42 886 A1 .
  • the present invention aims to allow obtaining a better vacuum than that (of the order of 0.01 mbar) that a single lug pump is capable of generating in a vacuum enclosure.
  • Another object of the present invention is to allow a draining flow rate which is greater at low pressure to be obtained than that which can be obtained using a single pin pump during a pumping operation to create a vacuum. in an empty enclosure.
  • the present invention also aims to allow a reduction in the electrical energy necessary for emptying a vacuum enclosure and maintaining the vacuum, as well as a drop in the temperature of the outlet gases.
  • a pumping system to generate a vacuum, comprising a main vacuum pump which is a lug pump having a gas inlet suction connected to a vacuum enclosure and a gas outlet discharge leading into a gas discharge duct to a gas exhaust outlet outside the pumping system.
  • the pumping system also comprises a non-return valve positioned between the gas outlet discharge and the gas exhaust outlet, as well as an auxiliary vacuum pump which has its motor and which is connected in parallel with the non-return valve. -return.
  • the auxiliary vacuum pump is arranged to start at the same time as the main vacuum pump and to pump all the time that the main vacuum pump pumps the gases contained in the vacuum enclosure and all the time that the main vacuum pump maintains a defined pressure in the vacuum enclosure.
  • the auxiliary vacuum pump can be of different types, including another lug pump, a screw type dry pump, a multi-stage Roots type pump, a membrane pump, a dry vane pump, a vane pump lubricated;
  • the auxiliary pump is operated continuously all the time that the main vacuum pump with lugs empties the vacuum enclosure, but also all the time that the main vacuum pump with lugs maintains a pressure defined (eg final vacuum) in the enclosure by evacuating the gases by its discharge.
  • a pressure defined eg final vacuum
  • the coupling of the main vacuum pump with lugs and of the auxiliary pump can be done without the need for specific measurements or devices (eg pressure, temperature, current sensors , etc.), neither servos, nor data management and without calculation. Consequently, the pumping system suitable for implementing the pumping method according to the present invention may comprise only a minimum number of components, be very simple and cost considerably less, compared with existing systems.
  • the main lug vacuum pump can operate at a single constant speed, that of the electrical network, or else rotate at variable speeds according to its own operating mode. Consequently, the complexity and the cost of the pumping system suitable for implementing the pumping method according to the present invention can be further reduced.
  • the auxiliary pump integrated in the pumping system can always operate according to the pumping method according to the invention without undergoing mechanical damage. Its dimensioning is conditioned by a minimum energy consumption for the operation of the device. Its nominal flow rate is chosen according to the volume of the exhaust duct between the main lug vacuum pump and the non-return valve. This flow rate can advantageously be from 1/500 to 1/20 of the nominal flow rate of the main lug vacuum pump, but can also be lower or higher than these values, in particular from 1/500 to 1/10 or even 1 / 500 to 1 / 5u nominal flow rate of the main vacuum pump.
  • the non-return valve placed in the duct downstream from the main lug vacuum pump can for example be a standard element available commercially, but it is also conceivable to design an element dedicated to the specific application. It is sized according to the nominal flow rate of the main lug vacuum pump. In particular, provision is made for the non-return valve to close when the suction pressure of the main lug vacuum pump is between 500 mbar absolute and the final vacuum (eg 100 mbar).
  • the auxiliary pump can be made of materials and / or with coatings with high chemical resistance to the substances and gases commonly used in the semiconductor industry.
  • the auxiliary pump is preferably small.
  • the auxiliary vacuum pump always pumps in the volume between the gas outlet discharge of the main vacuum pump with lugs and the non-return valve.
  • the sizing of the auxiliary vacuum pump aims for a minimum energy consumption of its motor. Its nominal flow rate is chosen according to the flow rate of the main vacuum pump with lugs, but also taking into account the volume that the gas evacuation pipe defines between the main vacuum pump and the non-return valve. This flow can be from 1/500 to 1/20 of the nominal flow rate of the main lug vacuum pump, but can also be lower or higher than these values.
  • the pressure is high, for example equal to atmospheric pressure. Due to the compression in the main lug vacuum pump, the pressure of the gases discharged at its outlet is higher than atmospheric pressure (if the gases at the outlet of the main pump are discharged directly to the atmosphere) or higher than the pressure at the inlet of another device connected downstream. This causes the non-return valve to open.
  • the pressure at the outlet of the main lug vacuum pump becomes that at the inlet of the auxiliary vacuum pump, that of its outlet always being the pressure in the duct after the non-return valve.
  • main lug vacuum pump consumes less and less energy for compression and produces less and less compression heat.
  • the figure 1 shows a pumping system SP for generating a vacuum, which is suitable for implementing a pumping method according to an embodiment of the present invention.
  • This pumping system SP comprises an enclosure 1, which is connected to the suction 2 of a main vacuum pump constituted by a lug pump 3.
  • the gas outlet discharge from the main lug vacuum pump 3 is connected to a discharge pipe 5.
  • a discharge check valve 6 is placed in the discharge pipe 5, which after this non-return valve continues into the gas outlet pipe 8.
  • the non-return valve 6, when 'it is closed, allows the formation of a volume 4, comprised between the gas outlet discharge from the main lug vacuum pump 3 and itself.
  • the pumping system SP also includes the auxiliary vacuum pump 7, connected in parallel to the non-return valve 6.
  • the suction of the auxiliary vacuum pump is connected to the volume 4 of the evacuation duct 5 and its discharge is connected to the conduit 8.
  • the auxiliary vacuum pump 7 is also started.
  • the main lug vacuum pump 3 draws the gases into the enclosure 1 through the conduit 2 connected to its inlet and compresses them to then discharge them on its outlet into the exhaust conduit 5 by the non-return valve 6
  • the closing pressure of the non-return valve 6 is reached, it closes.
  • the pumping of the auxiliary vacuum pump 7 gradually lowers the pressure in the volume 4 to the value of its limit pressure.
  • the power consumed by the main lug vacuum pump 3 gradually decreases. This occurs in a short time, for example for a certain cycle in 5 to 10 seconds depending on the ratio between the volume 4 and the nominal flow rate of the auxiliary vacuum pump 7, but can also last longer.
  • the auxiliary vacuum pump 7 can be another lug pump, a screw type dry pump, a multi-stage Roots pump, a membrane pump, a vane dry pump, a lubricated paddles or even an ejector.
  • the ejector can be either a "simple" ejector in the sense that the flow rate of its propellant gas comes from a distribution network on the industrial site, or equipped with a compressor which supplies the ejector the propellant gas flow at the pressure necessary for its operation. More specifically, this compressor can be driven by the main pump or, alternatively or by addition, independently, independent of the main pump. This compressor can draw atmospheric air or gases into the gas outlet pipe after the non-return valve. The presence of such a compressor makes the pump system independent of a source of compressed gas, which can respond to certain industrial environments.
  • the figure 2 shows an SPP pumping system suitable for implementing a pumping process not in accordance with the present invention.
  • the system shown in figure 2 shows the piloted pumping system SPP, further comprising suitable sensors 11, 12, 13 which control either the motor current (sensor 11) of the main lug vacuum pump 3, or the pressure (sensor 13) of the gases in the volume of the outlet pipe of the main lug vacuum pump, limited by the non-return valve 6, i.e. the temperature (sensor 12) of the gases in the volume of the outlet pipe of the main lug vacuum pump, limited by the non-return valve 6, a combination of these parameters.
  • the main lug vacuum pump 3 begins to pump the gases from the vacuum enclosure 1
  • parameters such as the current of its motor, the temperature and the pressure of the gases in the volume of the outlet duct 4 begin to change and reach threshold values detected by the sensors. After a delay, this causes the auxiliary vacuum pump to start.
  • these parameters return to the initial ranges (outside the setpoints) with a delay, the auxiliary vacuum pump is stopped.
  • the auxiliary vacuum pump can also be of the lug type, of the screw dry type, of the multi-stage Roots, of the membrane, of the paddle dryer, of the lubricated paddles or of an ejector (without or with compressor supplying its propellant gas), such as in the embodiment of the invention of the figure 1 .

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)

Description

Domaine technique de l'inventionTechnical field of the invention

La présente invention se rapporte au domaine des techniques du vide. Plus précisément, elle concerne à un système de pompage comprenant au moins une pompe à ergots, ainsi qu'un procédé de pompage au moyen de ce système de pompage.The present invention relates to the field of vacuum techniques. More specifically, it relates to a pumping system comprising at least one lug pump, as well as a method of pumping by means of this pumping system.

Art antérieurPrior art

Les objectifs généraux d'augmentation des performances des pompes à vide, de réduction des coûts des installations et de la consommation d'énergie dans les industries comme l'industrie chimique, l'industrie pharmaceutique, l'industrie du dépôt sous vide, l'industrie des semi-conducteurs, etc. ont conduit à des évolutions significatives en termes de performances, d'économie d'énergie, d'encombrement, dans les entrainements, etc.The general objectives of increasing the performance of vacuum pumps, reducing installation costs and energy consumption in industries such as the chemical industry, the pharmaceutical industry, the vacuum deposition industry, the semiconductor industry, etc. have led to significant changes in terms of performance, energy savings, space, training, etc.

L'état de la technique montre que pour améliorer le vide final, il faut par exemple ajouter des étages supplémentaires dans les pompes à vide de type Roots multi-étagées ou Claws (à ergots) multi-étagées. Pour les pompes à vide sèches de type à vis, il faut mettre des tours supplémentaires aux vis, et/ou augmenter le taux de compression interne.The state of the art shows that to improve the final vacuum, it is necessary, for example, to add additional stages in the multi-stage Roots type vacuum pumps or multi-stage Claws (with lugs). For screw type dry vacuum pumps, the screw must be rotated further, and / or the internal compression ratio increased.

La vitesse de rotation de la pompe joue un rôle très important, en définissant le fonctionnement de la pompe lors des différentes phases se succédant au cours du vidage de l'enceinte à vide. Avec les taux de compression interne des pompes disponibles sur le marché (dont l'ordre de grandeur se situe par exemple entre 2 et 20), la puissance électrique requise dans les premières phases de pompage, lorsque la pression à l'aspiration se trouve entre la pression atmosphérique et 100 mbar environ, c'est-à-dire lors de fonctionnement à débit massique fort, serait très élevée si la vitesse de rotation de la pompe ne pouvait être réduite.The speed of rotation of the pump plays a very important role, by defining the operation of the pump during the various successive phases during the emptying of the vacuum chamber. With the internal compression rates of pumps available on the market (whose order of magnitude is for example between 2 and 20), the electrical power required in the first pumping phases, when the suction pressure is between atmospheric pressure and approximately 100 mbar, that is to say during operation at high mass flow, would be very high if the rotation speed of the pump could not be reduced.

La solution triviale est d'utiliser un variateur de vitesse qui permet la réduction ou l'augmentation de la vitesse et par conséquent de la puissance en fonction des différents critères de type pression, courant maximal, couple limite, température, etc. Mais durant les périodes de fonctionnement en vitesse de rotation réduite il y a des baisses de débit à haute pression, le débit étant proportionnel à la vitesse de rotation. Aussi, la variation de vitesse par variateur de fréquence impose un coût et un encombrement supplémentaires.The trivial solution is to use a variable speed drive which allows the speed or consequently the power to be reduced or increased according to different criteria such as pressure, maximum current, torque limit, temperature, etc. But during periods of operation at reduced rotational speed there are drops in flow at high pressure, the flow being proportional to the rotational speed. Also, the variation of speed by frequency converter imposes an additional cost and size.

Une autre solution triviale est l'utilisation des clapets de type by-pass à certains étages, dans les pompes à vide multi-étagées de type Roots ou à ergots (Claws), ou à certaines positions bien définies le long des vis, dans les pompes à vide sèches de type à vis. Cette solution nécessite de nombreuses pièces et présente des problèmes de fiabilité.Another trivial solution is the use of bypass type valves on certain stages, in multi-stage vacuum pumps of Roots type or with lugs (Claws), or in certain well defined positions along the screws, in the screw type dry vacuum pumps. This solution requires many parts and presents reliability problems.

L'état de la technique concernant les systèmes de pompes à vide qui visent l'amélioration du vide final et l'augmentation du débit comprend typiquement des pompes booster de type Roots agencées en amont des pompes principales sèches. Ce type de systèmes est encombrant, fonctionne soit avec des clapets by-pass présentant des problèmes de fiabilité, soit en employant des moyens de mesure, contrôle, réglage ou asservissement. Cependant, ces moyens de contrôle, réglage ou asservissement doivent être pilotés d'une manière active, ce qui résulte forcément en une augmentation du nombre de composants du système, de sa complexité et de son coût.The state of the art concerning vacuum pump systems which aim to improve the final vacuum and increase the flow rate typically includes booster pumps of the Roots type arranged upstream of the main dry pumps. This type of system is bulky, works either with bypass valves presenting reliability problems, or by using means of measurement, control, adjustment or control. However, these means of control, adjustment or slaving must be actively controlled, which necessarily results in an increase in the number of system components, its complexity and its cost.

La demande de brevet US 2003/0068233 A1 propose un système de pompage à vide qui comprend une pompe principale, dont le refoulement est raccordé à un conduit d'échappement pourvu d'un clapet anti-retour. Une pompe auxiliaire est également prévue, en aval de la pompe principale. Cette pompe auxiliaire est raccordée en parallèle du clapet anti-retour.The patent application US 2003/0068233 A1 offers a vacuum pumping system which includes a main pump, the discharge of which is connected to an exhaust duct provided with a non-return valve. An auxiliary pump is also provided, downstream of the main pump. This auxiliary pump is connected in parallel with the non-return valve.

Des systèmes de pompage à vide comprenant une pompe principale et une pompe auxiliaire raccordée en parallèle d'un clapet anti-retour sont également connus des documents WO 2014/012896 A2 , JP 2007 100562 A , EP 1 243 795 A1 , DE 88 16 875 U1 et DE 38 42 886 A1 .Vacuum pumping systems comprising a main pump and an auxiliary pump connected in parallel with a non-return valve are also known from the documents. WO 2014/012896 A2 , JP 2007 100562 A , EP 1,243,795 A1 , DE 88 16 875 U1 and DE 38 42 886 A1 .

Résumé de l'inventionSummary of the invention

La présente invention a pour but de permettre l'obtention d'un vide meilleur que celui (de l'ordre de 0.01 mbar) qu'une seule pompe à ergots est capable de générer dans une enceinte à vide.The present invention aims to allow obtaining a better vacuum than that (of the order of 0.01 mbar) that a single lug pump is capable of generating in a vacuum enclosure.

La présente invention a aussi pour but de permettre l'obtention d'un débit de vidage qui soit supérieur à basse pression à celui qui peut être obtenu à l'aide d'une seule pompe à ergots lors d'un pompage pour réaliser un vide dans une enceinte à vide.Another object of the present invention is to allow a draining flow rate which is greater at low pressure to be obtained than that which can be obtained using a single pin pump during a pumping operation to create a vacuum. in an empty enclosure.

La présente invention a également pour but de permettre une réduction de l'énergie électrique nécessaire pour le vidage d'une enceinte à vide et le maintien du vide, ainsi qu'une baisse de la température des gaz de sortie.The present invention also aims to allow a reduction in the electrical energy necessary for emptying a vacuum enclosure and maintaining the vacuum, as well as a drop in the temperature of the outlet gases.

Ces buts de la présente invention sont atteints à l'aide d'un système de pompage pour générer un vide, comprenant une pompe à vide principale qui est une pompe à ergots ayant une aspiration d'entrée des gaz reliée à une enceinte à vide et un refoulement de sortie des gaz donnant dans un conduit d'évacuation des gaz vers une sortie d'échappement des gaz hors du système de pompage. Le système de pompage comprend en outre un clapet anti-retour positionné entre le refoulement de sortie des gaz et la sortie d'échappement des gaz, ainsi qu'une pompe à vide auxiliaire qui a son moteur et qui est raccordée en parallèle du clapet anti-retour. La pompe à vide auxiliaire est agencée de manière à se mettre en marche en même temps que la pompe à vide principale et à pomper tout le temps que la pompe à vide principale pompe les gaz contenus dans l'enceinte à vide et tout le temps que la pompe à vide principale maintient une pression définie dans l'enceinte à vide.These objects of the present invention are achieved using a pumping system to generate a vacuum, comprising a main vacuum pump which is a lug pump having a gas inlet suction connected to a vacuum enclosure and a gas outlet discharge leading into a gas discharge duct to a gas exhaust outlet outside the pumping system. The pumping system also comprises a non-return valve positioned between the gas outlet discharge and the gas exhaust outlet, as well as an auxiliary vacuum pump which has its motor and which is connected in parallel with the non-return valve. -return. The auxiliary vacuum pump is arranged to start at the same time as the main vacuum pump and to pump all the time that the main vacuum pump pumps the gases contained in the vacuum enclosure and all the time that the main vacuum pump maintains a defined pressure in the vacuum enclosure.

La pompe à vide auxiliaire peut être de différents types, notamment une autre pompe à ergots, une pompe sèche de type à vis, une pompe de type Roots multi-étagé, une pompe à membrane, une pompe sèche à palettes, une pompe à palettes lubrifiée;The auxiliary vacuum pump can be of different types, including another lug pump, a screw type dry pump, a multi-stage Roots type pump, a membrane pump, a dry vane pump, a vane pump lubricated;

L'invention a également pour objet un procédé de pompage au moyen d'un système de pompage tel que défini précédemment. Ce procédé comporte des étapes dans lesquelles :

  • la pompe à vide principale est mise en marche afin de pomper les gaz contenus dans l'enceinte à vide et de refouler ces gaz par son refoulement de sortie des gaz ;
  • en même temps que la pompe à vide principale, la pompe à vide auxiliaire est mise en marche ; et
  • la pompe à vide auxiliaire continue de pomper tout le temps que la pompe à vide principale pompe les gaz contenus dans l'enceinte à vide et tout le temps que la pompe à vide principale maintient une pression définie dans l'enceinte à vide.
The invention also relates to a pumping method by means of a pumping system as defined above. This process includes steps in which:
  • the main vacuum pump is started in order to pump the gases contained in the vacuum enclosure and to discharge these gases by its outlet gas outlet;
  • at the same time as the main vacuum pump, the auxiliary vacuum pump is started; and
  • the auxiliary vacuum pump continues to pump as long as the main vacuum pump pumps the gases contained in the vacuum enclosure and while the main vacuum pump maintains a defined pressure in the vacuum enclosure.

Dans le procédé selon l'invention, on fait fonctionner la pompe auxiliaire en continu tout le temps que la pompe à vide principale à ergots vide l'enceinte à vide, mais aussi tout le temps que la pompe à vide principale à ergots maintient une pression définie (p.ex. le vide final) dans l'enceinte en évacuant les gaz par son refoulement.In the method according to the invention, the auxiliary pump is operated continuously all the time that the main vacuum pump with lugs empties the vacuum enclosure, but also all the time that the main vacuum pump with lugs maintains a pressure defined (eg final vacuum) in the enclosure by evacuating the gases by its discharge.

Grâce au procédé selon l'invention, le couplage de la pompe à vide principale à ergots et de la pompe auxiliaire peut se faire sans nécessiter de mesures ni d'appareils spécifiques (p.ex. de capteurs de pression, de température, de courant, etc.), ni d'asservissements, ni de gestion de données et sans calcul. Par conséquent, le système de pompage adapté pour la mise en œuvre de du procédé de pompage selon la présente invention peut ne comprendre qu'un nombre minimal de composants, présenter une grande simplicité et coûter nettement moins cher, par rapport aux systèmes existants.Thanks to the method according to the invention, the coupling of the main vacuum pump with lugs and of the auxiliary pump can be done without the need for specific measurements or devices (eg pressure, temperature, current sensors , etc.), neither servos, nor data management and without calculation. Consequently, the pumping system suitable for implementing the pumping method according to the present invention may comprise only a minimum number of components, be very simple and cost considerably less, compared with existing systems.

Grâce au procédé selon l'invention, la pompe à vide principale à ergots peut fonctionner à une seule vitesse constante, celle du réseau électrique, ou bien tourner à des vitesses variables suivant son propre mode de fonctionnement. Par conséquent, la complexité et le coût du système de pompage adapté pour la mise en œuvre du procédé de pompage selon la présente invention peuvent être réduits davantage.Thanks to the method according to the invention, the main lug vacuum pump can operate at a single constant speed, that of the electrical network, or else rotate at variable speeds according to its own operating mode. Consequently, the complexity and the cost of the pumping system suitable for implementing the pumping method according to the present invention can be further reduced.

Par sa nature, la pompe auxiliaire intégrée dans le système de pompage peut toujours fonctionner suivant le procédé de pompage selon l'invention sans subir des dommages mécaniques. Son dimensionnement est conditionné par une consommation énergétique minimale pour le fonctionnement du dispositif. Son débit nominal est choisi en fonction du volume du conduit d'évacuation entre la pompe à vide principale à ergots et le clapet anti-retour. Ce débit peut être avantageusement de 1/500 à 1/20 du débit nominal de la pompe à vide principale à ergots, mais peut aussi être inférieur ou supérieur à ces valeurs, notamment de 1/500 à 1/10 ou bien de 1/500 à 1/5u débit nominal de la pompe à vide principale.By its nature, the auxiliary pump integrated in the pumping system can always operate according to the pumping method according to the invention without undergoing mechanical damage. Its dimensioning is conditioned by a minimum energy consumption for the operation of the device. Its nominal flow rate is chosen according to the volume of the exhaust duct between the main lug vacuum pump and the non-return valve. This flow rate can advantageously be from 1/500 to 1/20 of the nominal flow rate of the main lug vacuum pump, but can also be lower or higher than these values, in particular from 1/500 to 1/10 or even 1 / 500 to 1 / 5u nominal flow rate of the main vacuum pump.

Le clapet anti-retour, placé dans le conduit en aval de la pompe à vide principale à ergots peut par exemple être un élément standard disponible dans le commerce mais il est également imaginable de concevoir un élément dédié à l'application spécifique. Il est dimensionné suivant le débit nominal de la pompe à vide principale à ergots. En particulier, il est prévu que le clapet anti-retour se ferme quand la pression à l'aspiration de la pompe à vide principale à ergots se situe entre 500 mbar absolu et le vide final (p.ex. 100 mbar).The non-return valve, placed in the duct downstream from the main lug vacuum pump can for example be a standard element available commercially, but it is also conceivable to design an element dedicated to the specific application. It is sized according to the nominal flow rate of the main lug vacuum pump. In particular, provision is made for the non-return valve to close when the suction pressure of the main lug vacuum pump is between 500 mbar absolute and the final vacuum (eg 100 mbar).

Selon encore une autre variante, la pompe auxiliaire peut être réalisée en matières et/ou avec des revêtements à résistance chimique élevée aux substances et gaz communément utilisés dans l'industrie des semi-conducteurs.According to yet another variant, the auxiliary pump can be made of materials and / or with coatings with high chemical resistance to the substances and gases commonly used in the semiconductor industry.

La pompe auxiliaire est de préférence de petite taille.The auxiliary pump is preferably small.

De préférence, suivant le procédé de pompage employant le système de pompage selon l'invention, la pompe à vide auxiliaire pompe toujours dans le volume entre le refoulement de sortie des gaz de la pompe à vide principale à ergots et le clapet anti-retour.Preferably, according to the pumping method using the pumping system according to the invention, the auxiliary vacuum pump always pumps in the volume between the gas outlet discharge of the main vacuum pump with lugs and the non-return valve.

Le dimensionnement de la pompe à vide auxiliaire vise une consommation d'énergie minimale de son moteur. Son débit nominal est choisi en fonction du débit de la pompe à vide principale à ergots, mais aussi en prenant en compte le volume que le conduit d'évacuation des gaz délimite entre la pompe à vide principale et le clapet anti-retour. Ce débit peut être de 1/500 à 1/20 du débit nominal de la pompe à vide principale à ergots, mais peut aussi être inférieur ou supérieur à ces valeurs.The sizing of the auxiliary vacuum pump aims for a minimum energy consumption of its motor. Its nominal flow rate is chosen according to the flow rate of the main vacuum pump with lugs, but also taking into account the volume that the gas evacuation pipe defines between the main vacuum pump and the non-return valve. This flow can be from 1/500 to 1/20 of the nominal flow rate of the main lug vacuum pump, but can also be lower or higher than these values.

Au départ d'un cycle de vidage de l'enceinte, la pression y est élevée, par exemple égale à la pression atmosphérique. Vu la compression dans la pompe à vide principale à ergots, la pression des gaz refoulés à sa sortie est plus haute que la pression atmosphérique (si les gaz à la sortie de la pompe principale sont refoulés directement à l'atmosphère) ou plus haute que la pression à l'entrée d'un autre appareil connecté en aval. Cela provoque l'ouverture du clapet anti-retour.At the start of an emptying cycle of the enclosure, the pressure is high, for example equal to atmospheric pressure. Due to the compression in the main lug vacuum pump, the pressure of the gases discharged at its outlet is higher than atmospheric pressure (if the gases at the outlet of the main pump are discharged directly to the atmosphere) or higher than the pressure at the inlet of another device connected downstream. This causes the non-return valve to open.

Quand ce clapet anti-retour est ouvert, l'action de la pompe à vide auxiliaire est très faiblement ressentie, puisque la pression à son aspiration est presque égale à celle à son refoulement. En revanche, quand le clapet anti-retour se ferme à une certaine pression (parce que la pression dans l'enceinte a baissé entretemps), l'action de la pompe à vide auxiliaire provoque une réduction progressive de la différence de pression entre l'enceinte à vide et le conduit d'évacuation en amont du clapet.When this non-return valve is open, the action of the auxiliary vacuum pump is very slightly felt, since the pressure at its suction is almost equal to that at its discharge. On the other hand, when the non-return valve closes at a certain pressure (because the pressure in the enclosure has dropped in the meantime), the action of the auxiliary vacuum pump causes a gradual reduction in the pressure difference between the vacuum enclosure and the evacuation duct upstream of the valve.

La pression à la sortie de la pompe à vide principale à ergots devient celle à l'entrée de la pompe à vide auxiliaire, celle de sa sortie étant toujours la pression dans le conduit après le clapet anti-retour. Plus la pompe à vide auxiliaire pompe, plus la pression à la sortie de la pompe à vide principale à ergots, dans le volume limité par le clapet anti-retour fermé, se réduit et par conséquent la différence de pression entre l'enceinte et la sortie de la pompe à vide principale à ergots baisse. Cette faible différence réduit les fuites internes dans la pompe à vide principale à ergots et engendre une baisse de la pression dans l'enceinte, ce qui améliore le vide final.The pressure at the outlet of the main lug vacuum pump becomes that at the inlet of the auxiliary vacuum pump, that of its outlet always being the pressure in the duct after the non-return valve. The more the auxiliary vacuum pump pumps, the lower the pressure at the outlet of the main lug vacuum pump, in the volume limited by the closed non-return valve, and consequently the pressure difference between the enclosure and the output of the main vacuum pump with drop pins. This small difference reduces internal leakage in the main lug vacuum pump and causes the pressure in the enclosure to drop, which improves the final vacuum.

De plus, la pompe à vide principale à ergots consomme de moins en moins d'énergie pour la compression et produit de moins en moins de chaleur de compression.In addition, the main lug vacuum pump consumes less and less energy for compression and produces less and less compression heat.

D'un autre côté, il est aussi évident que l'étude du concept mécanique cherche à réduire le volume entre le refoulement de sortie des gaz de la pompe à vide principale à ergots et le clapet anti-retour dans le but de pouvoir y faire baisser la pression plus vite.On the other hand, it is also obvious that the study of the mechanical concept seeks to reduce the volume between the gas outlet discharge from the main vacuum pump with pins and non-return valve in order to be able to lower the pressure faster.

Brève description des dessinsBrief description of the drawings

Les particularités et les avantages de la présente invention apparaîtront avec plus de détails dans le cadre de la description qui suit avec des exemples de réalisation donnés à titre illustratif et non limitatif en référence aux dessins ci-annexés qui représentent :

  • la figure 1 représente de manière schématique un système de pompage adapté pour la réalisation d'un procédé de pompage selon un mode de réalisation de la présente invention ; et
  • la figure 2 représente de manière schématique un système de pompage adapté pour la réalisation d'un procédé de pompage non conforme à la présente invention.
The features and advantages of the present invention will appear in more detail in the context of the description which follows with examples of embodiment given by way of illustration and not limitation with reference to the attached drawings which represent:
  • the figure 1 shows schematically a pumping system suitable for carrying out a pumping method according to an embodiment of the present invention; and
  • the figure 2 shows schematically a pumping system suitable for carrying out a pumping process not in accordance with the present invention.

Description détaillée des modes de réalisation de l'inventionDetailed description of the embodiments of the invention

La figure 1 représente un système de pompage SP pour générer un vide, qui est adapté pour la mise en œuvre d'un procédé de pompage selon un mode de réalisation de la présente invention.The figure 1 shows a pumping system SP for generating a vacuum, which is suitable for implementing a pumping method according to an embodiment of the present invention.

Ce système de pompage SP comporte une enceinte 1, laquelle est reliée à l'aspiration 2 d'une pompe à vide principale constituée par une pompe à ergots 3. Le refoulement de sortie des gaz de la pompe à vide principale à ergots 3 est relié à un conduit d'évacuation 5. Un clapet anti-retour de refoulement 6 est placé dans le conduit d'évacuation 5, qui après ce clapet anti-retour continue en conduit de sortie des gaz 8. Le clapet anti-retour 6, lorsqu'il est fermé, permet la formation d'un volume 4, compris entre le refoulement de sortie des gaz de la pompe à vide principale à ergots 3 et lui-même.This pumping system SP comprises an enclosure 1, which is connected to the suction 2 of a main vacuum pump constituted by a lug pump 3. The gas outlet discharge from the main lug vacuum pump 3 is connected to a discharge pipe 5. A discharge check valve 6 is placed in the discharge pipe 5, which after this non-return valve continues into the gas outlet pipe 8. The non-return valve 6, when 'it is closed, allows the formation of a volume 4, comprised between the gas outlet discharge from the main lug vacuum pump 3 and itself.

Le système de pompage SP comporte aussi la pompe à vide auxiliaire 7, branchée en parallèle au clapet anti-retour 6. L'aspiration de la pompe à vide auxiliaire est reliée au volume 4 du conduit d'évacuation 5 et son refoulement est relié au conduit 8.The pumping system SP also includes the auxiliary vacuum pump 7, connected in parallel to the non-return valve 6. The suction of the auxiliary vacuum pump is connected to the volume 4 of the evacuation duct 5 and its discharge is connected to the conduit 8.

Dès la mise en route de la pompe à vide principale à ergots 3, la pompe à vide auxiliaire 7 est mise en route elle-aussi. La pompe à vide principale à ergots 3 aspire les gaz dans l'enceinte 1 par le conduit 2 branché à son entrée et les comprime pour les refouler par la suite à sa sortie dans le conduit d'évacuation 5 par le clapet anti-retour 6. Lorsque la pression de fermeture du clapet anti-retour 6 est atteinte, il se ferme. A partir de ce moment le pompage de la pompe à vide auxiliaire 7 fait baisser progressivement la pression dans le volume 4 jusqu'à la valeur de sa pression limite. En parallèle, la puissance consommée par la pompe à vide principale à ergots 3 baisse progressivement. Cela se produit en un court laps de temps, par exemple pour un certain cycle en 5 à 10 secondes en fonction du rapport entre le volume 4 et le débit nominal de la pompe à vide auxiliaire 7, mais peut durer aussi plus longtemps.As soon as the main lug vacuum pump 3 is started, the auxiliary vacuum pump 7 is also started. The main lug vacuum pump 3 draws the gases into the enclosure 1 through the conduit 2 connected to its inlet and compresses them to then discharge them on its outlet into the exhaust conduit 5 by the non-return valve 6 When the closing pressure of the non-return valve 6 is reached, it closes. From this moment, the pumping of the auxiliary vacuum pump 7 gradually lowers the pressure in the volume 4 to the value of its limit pressure. In parallel, the power consumed by the main lug vacuum pump 3 gradually decreases. This occurs in a short time, for example for a certain cycle in 5 to 10 seconds depending on the ratio between the volume 4 and the nominal flow rate of the auxiliary vacuum pump 7, but can also last longer.

Avec un ajustement judicieux du débit de la pompe à vide auxiliaire 7 et de la pression de fermeture du clapet anti-retour 6 en fonction du débit de la pompe à vide principale à ergots 3 et du volume de l'enceinte 1, il est en outre possible de réduire le temps avant la fermeture du clapet anti-retour 6 par rapport à la durée du cycle de vidage et donc réduire la quantité d'énergie consommée pendant ce temps de fonctionnement de pompe auxiliaire 7, avec l'avantage de la simplicité et de la fiabilité du système.With a judicious adjustment of the flow rate of the auxiliary vacuum pump 7 and the closing pressure of the non-return valve 6 as a function of the flow rate of the main vacuum pump with pins 3 and of the volume of the enclosure 1, it is in further possible to reduce the time before closing the non-return valve 6 compared to the duration of the emptying cycle and therefore reduce the amount of energy consumed during this operating time of auxiliary pump 7, with the advantage of simplicity and the reliability of the system.

Selon les différentes possibilités de combinaison, la pompe à vide auxiliaire 7 peut être une autre pompe à ergots, une pompe sèche de type à vis, une pompe Roots multi-étagée, une pompe à membrane, une pompe sèche à palettes, une pompe à palettes lubrifiée ou même un éjecteur. Dans ce dernier cas, l'éjecteur peut être soit un éjecteur « simple » dans le sens que le débit de son gaz propulseur vient d'un réseau de distribution sur le site industriel, soit muni d'un compresseur qui fournit à l'éjecteur le débit de gaz propulseur à la pression nécessaire pour son fonctionnement. Plus spécifiquement, ce compresseur peut être entraîné par la pompe principale ou, alternativement ou en addition, de manière autonome, indépendante de la pompe principale. Ce compresseur peut aspirer l'air atmosphérique ou des gaz dans le conduit de sortie de gaz après le clapet anti-retour. La présence d'un tel compresseur rend le système de pompes indépendant d'une source de gaz comprimé, ce qui peut répondre à certains environnements industriels.According to the different combination possibilities, the auxiliary vacuum pump 7 can be another lug pump, a screw type dry pump, a multi-stage Roots pump, a membrane pump, a vane dry pump, a lubricated paddles or even an ejector. In the latter case, the ejector can be either a "simple" ejector in the sense that the flow rate of its propellant gas comes from a distribution network on the industrial site, or equipped with a compressor which supplies the ejector the propellant gas flow at the pressure necessary for its operation. More specifically, this compressor can be driven by the main pump or, alternatively or by addition, independently, independent of the main pump. This compressor can draw atmospheric air or gases into the gas outlet pipe after the non-return valve. The presence of such a compressor makes the pump system independent of a source of compressed gas, which can respond to certain industrial environments.

La figure 2 représente un système de pompage SPP adapté pour la mise en œuvre d'un procédé de pompage non conforme à la présente invention.The figure 2 shows an SPP pumping system suitable for implementing a pumping process not in accordance with the present invention.

Par rapport au système montré à la figure 1, le système représenté à la figure 2 représente le système de pompage piloté SPP, comprenant en outre des capteurs adéquats 11, 12, 13 qui contrôlent soit le courant du moteur (capteur 11) de la pompe à vide principale à ergots 3, soit la pression (capteur 13) des gaz dans le volume du conduit de sortie de la pompe à vide principale à ergots, limité par le clapet anti-retour 6, soit la température (capteur 12) des gaz dans le volume du conduit à sortie de la pompe à vide principale à ergots, limité par le clapet anti-retour 6, soit une combinaison de ces paramètres. En effet, quand la pompe à vide principale à ergots 3 commence à pomper les gaz de l'enceinte à vide 1 les paramètres tels le courant de son moteur, la température et la pression des gaz dans le volume du conduit de sortie 4 commencent à se modifier et atteignent des valeurs de seuil détectées par les capteurs. Après une temporisation cela provoque la mise en marche de la pompe à vide auxiliaire 7. Quand ces paramètres repassent dans des plages initiales (hors consignes) avec une temporisation la pompe à vide auxiliaire est arrêtée.Compared to the system shown in figure 1 , the system shown in figure 2 shows the piloted pumping system SPP, further comprising suitable sensors 11, 12, 13 which control either the motor current (sensor 11) of the main lug vacuum pump 3, or the pressure (sensor 13) of the gases in the volume of the outlet pipe of the main lug vacuum pump, limited by the non-return valve 6, i.e. the temperature (sensor 12) of the gases in the volume of the outlet pipe of the main lug vacuum pump, limited by the non-return valve 6, a combination of these parameters. In fact, when the main lug vacuum pump 3 begins to pump the gases from the vacuum enclosure 1, parameters such as the current of its motor, the temperature and the pressure of the gases in the volume of the outlet duct 4 begin to change and reach threshold values detected by the sensors. After a delay, this causes the auxiliary vacuum pump to start. When these parameters return to the initial ranges (outside the setpoints) with a delay, the auxiliary vacuum pump is stopped.

Dans le mode de réalisation de la figure 2, la pompe à vide auxiliaire peut aussi être de type à ergots, de type sèche à vis, Roots multi-étagé, à membrane, sèche à palettes, à palettes lubrifiées ou un éjecteur (sans ou avec compresseur fournissant son gaz propulseur), comme dans le mode de réalisation de l'invention de la figure 1.In the embodiment of the figure 2 , the auxiliary vacuum pump can also be of the lug type, of the screw dry type, of the multi-stage Roots, of the membrane, of the paddle dryer, of the lubricated paddles or of an ejector (without or with compressor supplying its propellant gas), such as in the embodiment of the invention of the figure 1 .

Bien que divers modes de réalisation aient été décrits, on comprend bien qu'il n'est pas concevable d'exposer de manière exhaustive tous les modes de réalisation possibles. Il est bien sûr envisageable de remplacer un moyen décrit par un autre moyen sans sortir du cadre de la présente invention telle que définie par les revendications. Toutes ces modifications font partie des connaissances communes d'un homme du métier dans le domaine de la technologie du vide.Although various embodiments have been described, it will be understood that it is not conceivable to set out exhaustively all the possible embodiments. It is of course possible to replace a means described by another means without departing from the scope of the present invention as defined by the claims. All these modifications are part of the common knowledge of a person skilled in the art in the field of vacuum technology.

Claims (13)

  1. Pumping system for generating a vacuum (SP), comprising a main vacuum pump which is a claw pump (3) having a gas suction inlet (2) connected to a vacuum chamber (1) and a gas discharge outlet (4) leading into a gas evacuation conduit (5) in the direction of a gas exhaust outlet (8) outside the pumping system,
    the pumping system further comprising:
    - a non-return valve (6) positioned between the gas discharge outlet (4) and the gas exhaust outlet (8), and
    - an auxiliary vacuum pump (7) which has its motor and which is connected in parallel to the non-return valve,
    the pumping system being characterized in that the auxiliary vacuum pump (7) is designed in such a way as to go into operation at the same time as the main vacuum pump (3) and to pump all the while that the main vacuum pump (3) pumps the gases contained in the vacuum chamber (1) and all the while that the main vacuum pump (3) maintains a defined pressure in the vacuum chamber (1).
  2. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) is a dry screw pump.
  3. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) is a claw pump.
  4. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) is a multi-stage Roots pump.
  5. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) is a diaphragm pump.
  6. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) a dry rotary vane pump.
  7. Pumping system according to claim 1, characterized in that the auxiliary vacuum pump (7) is a lubricated rotary vane pump.
  8. Pumping system according to any one of the preceding claims, characterized in that the main vacuum pump (3) is configured to operate only at a single constant speed.
  9. Pumping system according to any one of the preceding claims, characterized in that the nominal flow rate of the auxiliary vacuum pump (7) is from 1/500 to 1/5 of the nominal flow rate of the main vacuum pump (3).
  10. Pumping system according to any one of the preceding claims, characterized in that the non-return valve (6) is configured to close when the pressure at the suction end of the main vacuum pump (3) is less than 500 mbar absolute.
  11. Pumping method by means of a pumping system (SP) according to any one of the preceding claims, characterized in that
    - the main vacuum pump (3) is started up in order to pump the gases contained in the vacuum chamber (1) and to discharge these gases through its gas discharge outlet (4);
    - the auxiliary vacuum pump (7) is started up simultaneously with the main vacuum pump (3); and
    - the auxiliary vacuum pump (7) continues to pump all the while that the main vacuum pump (3) pumps the gases contained in the vacuum chamber (1) and all the while that the main vacuum pump (3) maintains a defined pressure in the vacuum chamber (1).
  12. Pumping method according to claim 11, characterized in that the auxiliary vacuum pump (7) pumps <at> a flow rate on the order of 1/500 to 1/20 of the nominal flow rate of the main vacuum pump (3).
  13. Pumping method according to any one of the claims 11 and 12, characterized in that the non-return valve (6) closes when the pressure at the suction end of the main vacuum pump (3) is less than 500 mbar absolute.
EP14781160.8A 2014-10-02 2014-10-02 Pumping system for generating a vacuum and method for pumping by means of this pumping system Revoked EP3201469B1 (en)

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PL14781160T PL3201469T3 (en) 2014-10-02 2014-10-02 Pumping system for generating a vacuum and method for pumping by means of this pumping system

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PCT/EP2014/071197 WO2016050313A1 (en) 2014-10-02 2014-10-02 Pumping system for generating a vacuum and method for pumping by means of this pumping system

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US (1) US10808730B2 (en)
EP (1) EP3201469B1 (en)
JP (1) JP6512674B2 (en)
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US10808730B2 (en) 2020-10-20
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WO2016050313A1 (en) 2016-04-07
JP2017531754A (en) 2017-10-26
RU2674297C2 (en) 2018-12-06
KR102330815B1 (en) 2021-11-24
BR112017006572B1 (en) 2022-08-23
DK3201469T3 (en) 2020-04-27
JP6512674B2 (en) 2019-05-15
CN107002681A (en) 2017-08-01
TWI696760B (en) 2020-06-21
CA2961979A1 (en) 2016-04-07
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US20170284394A1 (en) 2017-10-05
RU2017114342A (en) 2018-11-07

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