EP0426078B1 - Method of operating a volumetric pump - Google Patents

Method of operating a volumetric pump Download PDF

Info

Publication number
EP0426078B1
EP0426078B1 EP90120721A EP90120721A EP0426078B1 EP 0426078 B1 EP0426078 B1 EP 0426078B1 EP 90120721 A EP90120721 A EP 90120721A EP 90120721 A EP90120721 A EP 90120721A EP 0426078 B1 EP0426078 B1 EP 0426078B1
Authority
EP
European Patent Office
Prior art keywords
gas
pump
stator
clearance
operating
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.)
Revoked
Application number
EP90120721A
Other languages
German (de)
French (fr)
Other versions
EP0426078A1 (en
Inventor
Jean-Marie Crinquette
Eric Taberlet
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.)
Alcatel CIT SA
Original Assignee
Alcatel CIT SA
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9387014&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0426078(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Alcatel CIT SA filed Critical Alcatel CIT SA
Priority to AT90120721T priority Critical patent/ATE92159T1/en
Publication of EP0426078A1 publication Critical patent/EP0426078A1/en
Application granted granted Critical
Publication of EP0426078B1 publication Critical patent/EP0426078B1/en
Anticipated expiration legal-status Critical
Revoked 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
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C27/00—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids

Definitions

  • the present invention relates to a method of operating a positive displacement pump or primary vacuum pump, comprising a stator and a rotor rotating in the stator, while maintaining a predetermined leakage game with respect to the latter.
  • Positive displacement pumps are capable of creating pressures from 0.001 to 0.0001 millibars, by driving back against the atmosphere.
  • the characteristic curve of the volume flow S (in m3 / h) as a function of the pressure P (in millibars) of such a pump depends on the play existing between the rotor and the stator of the pump.
  • Volume flow S / pressure P diagrams have been represented in FIG. 1. Each of the curves corresponds to a given clearance, the clearance increasing from one curve to another according to the arrow j.
  • the document GBA 947383 describes a positive displacement compressor of the twin screw type in which a liquid such as oil is injected into the machine so as to ensure a seal by liquid seal.
  • a liquid such as oil
  • such an injection is incompatible with a clean vacuum.
  • the constant problem posed to the pump manufacturer is to produce a pump which does not seize up and which has the minimum clearance between the rotor and the stator.
  • An object of the present invention is to provide a vacuum pump in which the pumping efficiency is optimal, without mechanical modifications thereof.
  • This object is achieved by injecting into the clearance between the rotor and the stator, a gas of molecular mass different from that of the pumped gas.
  • the European document EP-A-320956 (on which the preamble of claim 1 is based) describes a positive displacement pump into which an inert gas, nitrogen in the example cited, is injected into the working chambers of the pump, so as to reduce the partial pressure of ammonium chloride which is produced during the manufacture of silicon nitride.
  • an inert gas nitrogen in the example cited
  • ammonium chloride is deposited on the walls of the stator and the rotor.
  • the introduction of nitrogen decreases the partial pressure of ammonium chloride so that it no longer deposits on the walls.
  • the gas introduced here nitrogen has a lower molecular mass than that of the pumped gas.
  • the subject of the invention is therefore a method of operating a positive displacement pump, comprising a rotor rotating in a stator with a given clearance, used for pumping a gas or a mixture of gases of given molecular mass, and comprising means for injecting a gas into the above-mentioned set, characterized in that said injected gas has a higher molecular mass than that of the gas or of the pumped gas mixture.
  • the flow rate of injected gas is between 3 and 15 times the flow rate of pumped gas.
  • the flow rate of injected gas is adjustable.
  • the invention is specified on an example of a pump, namely a multi-stage Roots type pump, but it should be understood that the invention applies to any type of positive displacement pump such as vane pump, cylindrical or conical groove pump helical, twin screw pump, etc.
  • FIG. 2 schematically represents a multi-stage Roots pump having three stages 10, 20 and 30 respectively comprising stators 11, 21, 31 and rotors 12, 13; 22, 23; 32, 33.
  • the reference 4 designates the admission of stage 10, 14 is the discharge of stage 10 and the admission of stage 20, 24 is the discharge of stage 20 and the admission of stage 30, 34 is the delivery of stage 30.
  • a means for injecting, within the clearance 35 between the rotor and the stator of the stage, a gas higher molecular weight than that of the pumped gas. This is achieved for example by a nozzle 40 formed in the stator and connected to an auxiliary gas source, not shown, with adjustable flow rate.
  • any other gas injection means can be used such as for example multiple orifices in the wall of the stator, slot in the stator, porous part of the wall of the stator, etc.
  • molecular mass 28 can be injected.
  • This gas will advantageously be injected with a flow rate equal to several times that of the pumped gas, for example with a flow rate of between 3 times and 15 times that of the pumped gas.
  • This injected gas produces a kind of molecular seal which prevents the molecules of pumped gas from going in the direction of delivery-inlet, so that the efficiency of the pump is improved.
  • the invention finds application for any type of positive displacement pump.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Reciprocating Pumps (AREA)
  • Non-Positive Displacement Air Blowers (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)

Abstract

The object of the invention is a volumetric pump comprising a rotor turning in a stator with a given clearance, used for the pumping of a gas or a gas mixture of given molecular mass, characterised in that it comprises means for injecting into the said clearance a gas of higher molecular mass than that of the pumped gas or gas mixture. Applications to vane pumps, Roots pumps, double cylindrical or conical screw pumps, etc. <IMAGE>

Description

La présente invention concerne un procédé de fonctionnement d'une pompe volumétrique ou pompe à vide primaire, comportant un stator et un rotor tournant dans le stator, en conservant un jeu de fuite prédéterminé par rapport à ce dernier.The present invention relates to a method of operating a positive displacement pump or primary vacuum pump, comprising a stator and a rotor rotating in the stator, while maintaining a predetermined leakage game with respect to the latter.

Les pompes volumétriques sont capables de créer des pressions de 0,001 à 0,0001 millibars, en refoulant contre l'atmosphère. La courbe caractéristique du débit volumique S (en m³/h) en fonction de la pression P (en millibars) d'une telle pompe dépend du jeu existant entre le rotor et le stator de la pompe. Des diagrammes débit volumique S / pression P ont été représentés dans la figure 1. Chacune des courbes correspond à un jeu donné, le jeu augmentant d'une courbe à l'autre selon la flèche j.Positive displacement pumps are capable of creating pressures from 0.001 to 0.0001 millibars, by driving back against the atmosphere. The characteristic curve of the volume flow S (in m³ / h) as a function of the pressure P (in millibars) of such a pump depends on the play existing between the rotor and the stator of the pump. Volume flow S / pressure P diagrams have been represented in FIG. 1. Each of the curves corresponds to a given clearance, the clearance increasing from one curve to another according to the arrow j.

Il est bien évident que le constructeur d'une pompe à vide choisit une valeur du jeu entre le rotor et le stator en réalisant un compromis entre deux objectifs antagonistes. Afin d'éviter tout grippage dû par exemple à la dilatation différentielle entre le stator et le rotor, le constructeur est amené à choisir un jeu important. En revanche, il est conduit à choisir le jeu le plus faible possible pour améliorer les caractéristiques de la pompe, comme le suggèrent à l'évidence les courbes caractéristiques de la figure 1.It is quite obvious that the manufacturer of a vacuum pump chooses a value of the play between the rotor and the stator by realizing a compromise between two antagonistic objectives. In order to avoid any seizure due for example to the differential expansion between the stator and the rotor, the manufacturer has to choose a large clearance. On the other hand, it is necessary to choose the smallest possible clearance to improve the characteristics of the pump, as is evident from the characteristic curves of Figure 1.

Le document GBA 947383 décrit un compresseur volumétrique de type à double vis dans lequel un liquide tel que de l'huile est injecté dans la machine de façon à assurer une étanchéité par joint liquide. Cependant dans le cas de pompes à vide, une telle injection est incompatible avec un vide propre.The document GBA 947383 describes a positive displacement compressor of the twin screw type in which a liquid such as oil is injected into the machine so as to ensure a seal by liquid seal. However, in the case of vacuum pumps, such an injection is incompatible with a clean vacuum.

Le problème constant posé au constructeur de pompe est de réaliser une pompe ne grippant pas et ayant le minimum de jeu entre le rotor et le stator.The constant problem posed to the pump manufacturer is to produce a pump which does not seize up and which has the minimum clearance between the rotor and the stator.

Il a été proposé, dans la demande de brevet français n° 89 11302 au nom de la Demanderesse, de réliser une pompe dans laquelle le jeu est rendu variable pendant le pompage grâce à une partie élastiquement déformable de la paroi du rotor et/ou du stator, ou grâce à un déplacement relatif du rotor par rapport au stator.It has been proposed, in French patent application No. 89 11302 in the name of the Applicant, to make a pump in which the clearance is made variable during pumping thanks to an elastically deformable part of the wall of the rotor and / or of the stator, or by relative displacement of the rotor relative to the stator.

Cette solution résoud le problème posé, mais nécessite d'apporter à la pompe un certain nombre de modifications mécaniques qui en augmentent le prix de revient.This solution solves the problem, but requires making a certain number of mechanical modifications to the pump which increase the cost price.

Un but de la présente invention est de réaliser une pompe à vide dans laquelle le rendement de pompage est optimal, sans modifications mécaniques de celle-ci.An object of the present invention is to provide a vacuum pump in which the pumping efficiency is optimal, without mechanical modifications thereof.

Ce but est atteint en injectant dans le jeu compris entre le rotor et le stator, un gaz de masse moléculaire différente de celle du gaz pompé.This object is achieved by injecting into the clearance between the rotor and the stator, a gas of molecular mass different from that of the pumped gas.

On notera que le document européen EP-A-320956 (sur lequel est basé le préambule de la revendication 1) décrit une pompe volumétrique dans laquelle on injecte un gaz inerte, de l'azote dans l'exemple cité, dans les chambres de travail de la pompe, de manière à diminuer la pression partielle de chlorure d'ammonium qui est produit lors de la fabrication de nitrure de silicium. En effet dans les parties haute pression de la pompe, le chlorure d'ammonium se dépose sur les parois du stator et du rotor. L'introduction d'azote diminue la pression partielle de chlorure d'ammonium de telle sorte qu'il ne se dépose plus sur les parois.Note that the European document EP-A-320956 (on which the preamble of claim 1 is based) describes a positive displacement pump into which an inert gas, nitrogen in the example cited, is injected into the working chambers of the pump, so as to reduce the partial pressure of ammonium chloride which is produced during the manufacture of silicon nitride. In fact, in the high pressure parts of the pump, ammonium chloride is deposited on the walls of the stator and the rotor. The introduction of nitrogen decreases the partial pressure of ammonium chloride so that it no longer deposits on the walls.

Le gaz introduit ici: l'azote a une masse moléculaire moins élevée que celle du gaz pompé.The gas introduced here: nitrogen has a lower molecular mass than that of the pumped gas.

L'invention a ainsi pour objet un procédé de fonctionnement d'une pompe volumétrique, comprenant un rotor tournant dans un stator avec un jeu donné, utilisée pour le pompage d'un gaz ou d'un mélange de gaz de masse moléculaire donnée, et comportant des moyens pour injecter un gaz dans le jeu précité, caractérisé par le fait que ledit gaz injecté est de masse moléculaire plus élevée que celle du gaz ou du mélange de gaz pompé.The subject of the invention is therefore a method of operating a positive displacement pump, comprising a rotor rotating in a stator with a given clearance, used for pumping a gas or a mixture of gases of given molecular mass, and comprising means for injecting a gas into the above-mentioned set, characterized in that said injected gas has a higher molecular mass than that of the gas or of the pumped gas mixture.

De préférence, le débit de gaz injecté est compris entre 3 et 15 fois le débit de gaz pompé.Preferably, the flow rate of injected gas is between 3 and 15 times the flow rate of pumped gas.

Avantageusement, le débit de gaz injecté est réglable.Advantageously, the flow rate of injected gas is adjustable.

L'invention sera bien comprise par la description donnée ci-après d'un mode préféré de réalisation de l'invention, en référence au dessin ci-annexé dans lequel :

  • la figure 1 est un diagramme représentant, en fonction de la pression P, le débit volumique S d'une pompe pour diverses valeurs du jeu,
  • la figure 2 est une vue de principe d'une pompe Roots multiétagée,
  • la figure 3 est une vue en coupe axiale d'un étage de pompe Roots munie du dispositif de l'invention.
The invention will be better understood from the description given below of a preferred embodiment of the invention, with reference to the attached drawing in which:
  • FIG. 1 is a diagram representing, as a function of the pressure P, the volume flow rate S of a pump for various values of the clearance,
  • FIG. 2 is a principle view of a multi-stage Roots pump,
  • Figure 3 is an axial sectional view of a Roots pump stage provided with the device of the invention.

La figure 1 a déjà été commentée et on n'y reviendra pas.Figure 1 has already been commented on and we will not return to it.

L'invention est précisée sur un exemple de pompe, à savoir une pompe de type Roots multiétagée, mais on doit bien comprendre que l'invention s'applique à tout type de pompe volumétrique tel que pompe à palettes, pompe cylindrique ou conique à sillon hélicoïdal, pompe à double vis, etc.The invention is specified on an example of a pump, namely a multi-stage Roots type pump, but it should be understood that the invention applies to any type of positive displacement pump such as vane pump, cylindrical or conical groove pump helical, twin screw pump, etc.

La figure 2 représente schématiquement une pompe Roots multiétagée ayant trois étages 10, 20 et 30 comprenant repectivement des stators 11, 21, 31 et des rotors 12, 13 ; 22, 23 ; 32, 33. La référence 4 désigne l'admission de l'étage 10, 14 est le refoulement de l'étage 10 et l'admission de l'étage 20, 24 est le refoulement de l'étage 20 et l'admission de l'étage 30, 34 est le refoulement de l'étage 30.FIG. 2 schematically represents a multi-stage Roots pump having three stages 10, 20 and 30 respectively comprising stators 11, 21, 31 and rotors 12, 13; 22, 23; 32, 33. The reference 4 designates the admission of stage 10, 14 is the discharge of stage 10 and the admission of stage 20, 24 is the discharge of stage 20 and the admission of stage 30, 34 is the delivery of stage 30.

Conformément à l'invention, et comme il est représenté dans la figure 3 montrant le troisième étage de la pompe, il est prévu un moyen pour injecter, au sein même du jeu 35 entre le rotor et le stator de l'étage, un gaz de masse moléculaire plus élevée que celle du gaz pompé. Ceci est réalisé par exemple par un ajutage 40 pratiqué dans le stator et relié à une source de gaz auxiliaire non représentée, à débit réglable.According to the invention, and as shown in FIG. 3 showing the third stage of the pump, a means is provided for injecting, within the clearance 35 between the rotor and the stator of the stage, a gas higher molecular weight than that of the pumped gas. This is achieved for example by a nozzle 40 formed in the stator and connected to an auxiliary gas source, not shown, with adjustable flow rate.

Bien entendu, tout autre moyen d'injection de gaz peut être utilisé comme par exemple orifices multiples dans la paroi du stator, fente dans le stator, partie poreuse de la paroi du stator, etc....Of course, any other gas injection means can be used such as for example multiple orifices in the wall of the stator, slot in the stator, porous part of the wall of the stator, etc.

A titre d'exemple, si l'on pompe de l'hélium de masse moléculaire 4, on pourra injecter de l'azote, de masse moléculaire 28. Ce gaz sera avantageusement injecté avec un débit égal à plusieurs fois celui du gaz pompé, par exemple avec un débit compris entre 3 fois et 15 fois celui du gaz pompé.For example, if we pump mass helium molecular 4, nitrogen, of molecular mass 28 can be injected. This gas will advantageously be injected with a flow rate equal to several times that of the pumped gas, for example with a flow rate of between 3 times and 15 times that of the pumped gas.

Ce gaz injecté produit une sorte de joint moléculaire qui empêche les molécules de gaz pompé de se diriger dans le sens refoulement-admission, de sorte que le rendement de la pompe se trouve amélioré.This injected gas produces a kind of molecular seal which prevents the molecules of pumped gas from going in the direction of delivery-inlet, so that the efficiency of the pump is improved.

On peut modifier les caractéristiques de pompage, et en particulier amener le point de fonctionnement de la pompe à passer d'une courbe donnée de la figure 1 sur une autre courbe, comme si le jeu de la pompe était modifié, en réglant le débit du gaz injecté et/ou sa masse moléculaire.It is possible to modify the pumping characteristics, and in particular to bring the operating point of the pump to pass from a curve given in FIG. 1 onto another curve, as if the play of the pump was modified, by adjusting the flow rate of the injected gas and / or its molecular mass.

Il est possible de prévoir une injection sur plusieurs des étages de la pompe, par exemple sur les deux derniers étages.It is possible to provide an injection on several of the stages of the pump, for example on the last two stages.

L'invention trouve application pour tout type de pompe volumétrique.The invention finds application for any type of positive displacement pump.

Claims (3)

  1. A method for operating a positive displacement pump (30) comprising a rotor (32, 33) rotating in a stator (31) with a given amount of clearance (35), the pump being used for pumping a gas or a mixture of gases having a given molecular mass and comprising means for injecting a gas into said clearance, the pump being characterized in that said injected gas has a molecular mass which is higher than that of the gas or mixture of gases being pumped.
  2. A method for operating a pump according to claim 1, characterized in that the flow rate of the injected gas is adjustable.
  3. A method for operating a pump according to claims 1 or 2, characterized in that the flow rate of the injected gas lies in the range 3 times to 15 times the flow rate of the pumped gas.
EP90120721A 1989-11-02 1990-10-29 Method of operating a volumetric pump Revoked EP0426078B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT90120721T ATE92159T1 (en) 1989-11-02 1990-10-29 PROCEDURE FOR OPERATING A VOLUMETRIC PUMP.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8914354A FR2653831A1 (en) 1989-11-02 1989-11-02 VOLUMETRIC PUMP.
FR8914354 1989-11-02

Publications (2)

Publication Number Publication Date
EP0426078A1 EP0426078A1 (en) 1991-05-08
EP0426078B1 true EP0426078B1 (en) 1993-07-28

Family

ID=9387014

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90120721A Revoked EP0426078B1 (en) 1989-11-02 1990-10-29 Method of operating a volumetric pump

Country Status (7)

Country Link
EP (1) EP0426078B1 (en)
JP (1) JPH0730744B2 (en)
AT (1) ATE92159T1 (en)
DE (1) DE69002439T2 (en)
ES (1) ES2042175T3 (en)
FR (1) FR2653831A1 (en)
RU (1) RU1831588C (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2691382B1 (en) * 1992-05-22 1994-09-09 Cit Alcatel Pumping installation for pumping an enclosure containing gases mixed with solid particles or liable to generate solid particles or condensates.
DE19819538C2 (en) * 1998-04-30 2000-02-17 Rietschle Werner Gmbh & Co Kg Pressure suction pump
GB0719394D0 (en) * 2007-10-04 2007-11-14 Edwards Ltd A multi stage clam shell vacuum pump
DE102010044918A1 (en) * 2010-09-09 2012-03-15 Oerlikon Leybold Vacuum Gmbh Method for determination of working area of high vacuum pumping system, involves describing maximum amount of gas intakeable into high vacuum pump by upper border lines, and defining area lying below curves as working area
JP5627035B2 (en) * 2012-06-18 2014-11-19 株式会社ササクラ Evaporative air conditioner

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB385192A (en) * 1932-05-10 1932-12-22 Otto Becker Junior Improvements in and relating to rotary blowers
SE317154B (en) * 1959-01-15 1969-11-10 Svenska Rotor Maskiner Ab
JPS5517236A (en) * 1978-07-19 1980-02-06 Mitsubishi Electric Corp Manufacturing method of mica plate for commutator segment
JP2515831B2 (en) * 1987-12-18 1996-07-10 株式会社日立製作所 Screen vacuum pump

Also Published As

Publication number Publication date
FR2653831A1 (en) 1991-05-03
ES2042175T3 (en) 1993-12-01
DE69002439T2 (en) 1993-11-18
EP0426078A1 (en) 1991-05-08
DE69002439D1 (en) 1993-09-02
JPH0730744B2 (en) 1995-04-10
RU1831588C (en) 1993-07-30
JPH03160185A (en) 1991-07-10
ATE92159T1 (en) 1993-08-15

Similar Documents

Publication Publication Date Title
FR2738619A1 (en) ADJUSTABLE PALLET PUMP AS LUBRICATING PUMP
FR2723766A1 (en) SCREW VACUUM PUMP
FR2542385A1 (en) WHEAT PUMP
FR2533629A1 (en) APPARATUS AND METHOD FOR PURGING A TURBOCHARGER ENGINE WITH A DIVIDED EXHAUST SYSTEM
EP0426078B1 (en) Method of operating a volumetric pump
FR2787147A1 (en) REGENERATION PUMP WITH EXTENDED RANGE OF OPERATION
FR2643389A1 (en) CHEMICAL VAPOR DEPOSITION APPARATUS FOR FORMING THIN FILM
GB2278888A (en) A fuel pump with curved vapour channel
FR2556054A1 (en) DIFFUSER FOR CENTRIFUGAL COMPRESSOR
FR2743113A1 (en) DEVICE FOR PUMPING OR COMPRESSING A TANDEM BLADED POLYPHASTIC FLUID
EP3607204B1 (en) Pumping unit and use
FR2619867A1 (en) POLYETAGE MOLECULAR PUMP
EP1589227A1 (en) Multi-stage vacuum pump and pumping system having such a pump
FR2782543A1 (en) HYDRAULIC TRANSPORT DEVICE
FR2768189A1 (en) PUMPING METHOD AND SYSTEM FOR MIXING LIQUIDS
FR2519383A1 (en) Multiple stage radial compressor with water injection - has jet openings through walls of stages, arranged symmetrically about axis
FR2634820A1 (en) ROTARY PISTON MACHINE
FR2541388A1 (en) INJECTION FOR HIGH PRESSURE SCREW COMPRESSOR
FR2726608A1 (en) VACUUM PUMP PROVIDED WITH AN EPICYCLOIDAL GEAR DEMULTIPLICATION DEVICE
EP0143684B1 (en) Multi-stage series compressor
EP0600820B1 (en) Pump, especially for concentrated fibrous suspensions
FR2781528A1 (en) Flow unit for providing fuel flow from fuel tank has degassing valve fitted into flow unit breathing cover, which is integral with the rotor case; it has rotor blade annular channel connected to degassing valve
FR2510204A1 (en) MAGNETIC DRIVE PUMP, IN PARTICULAR FOR FUELS
FR2472094A1 (en) ROTARY PISTON PUMP WITH SEVERAL FLOORS
FR2482208A1 (en)

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: A1

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

17P Request for examination filed

Effective date: 19911104

17Q First examination report despatched

Effective date: 19920213

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

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

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

Ref country code: SE

Effective date: 19930728

Ref country code: DK

Effective date: 19930728

Ref country code: AT

Effective date: 19930728

REF Corresponds to:

Ref document number: 92159

Country of ref document: AT

Date of ref document: 19930815

Kind code of ref document: T

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19930804

REF Corresponds to:

Ref document number: 69002439

Country of ref document: DE

Date of ref document: 19930902

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

Ref country code: ES

Payment date: 19930910

Year of fee payment: 4

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

Ref country code: DE

Payment date: 19930922

Year of fee payment: 4

Ref country code: CH

Payment date: 19930922

Year of fee payment: 4

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

Ref country code: FR

Payment date: 19930930

Year of fee payment: 4

ITF It: translation for a ep patent filed

Owner name: JACOBACCI CASETTA & PERANI S.P.A.

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

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 19931029

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

Ref country code: LU

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

Effective date: 19931031

Ref country code: BE

Effective date: 19931031

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

Ref country code: NL

Payment date: 19931031

Year of fee payment: 4

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2042175

Country of ref document: ES

Kind code of ref document: T3

BERE Be: lapsed

Owner name: ALCATEL CIT

Effective date: 19931031

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: LEYBOLD AKTIENGESELLSCHAFT

Effective date: 19940426

NLR1 Nl: opposition has been filed with the epo

Opponent name: LEYBOLD AG.

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

Ref country code: ES

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

Effective date: 19941031

RDAG Patent revoked

Free format text: ORIGINAL CODE: 0009271

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

Free format text: STATUS: PATENT REVOKED

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

27W Patent revoked

Effective date: 19941216

GBPR Gb: patent revoked under art. 102 of the ep convention designating the uk as contracting state

Free format text: 941216

NLR2 Nl: decision of opposition