EP0519231B1 - Vorwarneinrichtung für Induktionsschmelzöfen - Google Patents

Vorwarneinrichtung für Induktionsschmelzöfen Download PDF

Info

Publication number
EP0519231B1
EP0519231B1 EP92108661A EP92108661A EP0519231B1 EP 0519231 B1 EP0519231 B1 EP 0519231B1 EP 92108661 A EP92108661 A EP 92108661A EP 92108661 A EP92108661 A EP 92108661A EP 0519231 B1 EP0519231 B1 EP 0519231B1
Authority
EP
European Patent Office
Prior art keywords
furnace lining
ceramic
electrodes
furnace
early warning
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
EP92108661A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0519231A2 (de
EP0519231A3 (en
Inventor
Manfred Dr.-Ing. Hopf
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.)
Feuerfest Ueberwachungstechnologie Saveway GmbH
Original Assignee
Feuerfest Ueberwachungstechnologie Saveway GmbH
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 Feuerfest Ueberwachungstechnologie Saveway GmbH filed Critical Feuerfest Ueberwachungstechnologie Saveway GmbH
Publication of EP0519231A2 publication Critical patent/EP0519231A2/de
Publication of EP0519231A3 publication Critical patent/EP0519231A3/de
Application granted granted Critical
Publication of EP0519231B1 publication Critical patent/EP0519231B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D21/00—Arrangement of monitoring devices; Arrangement of safety devices
    • F27D21/0021—Devices for monitoring linings for wear

Definitions

  • the invention relates to a pre-warning device for breakthroughs of metal melts on ceramic furnace linings of melting furnaces, in particular induction melting furnaces with electrodes or electrode network to be arranged on the respective furnace lining, in particular on the outside thereof, the electrodes being divided into two groups of different polarity, spaced apart and for determining the electrical, temperature-dependent resistance of the furnace lining between the two electrode groups can be connected to an evaluation unit (FR-A 2427569).
  • an evaluation unit FR-A 2427569
  • the ceramic furnace linings are subject to very hard thermal, chemical and mechanical stresses during operation. This results in washouts and possibly cracks that can penetrate to the inductor in an induction melting furnace. If penetration of the molten metal towards the inductor is not recognized in good time, the induction melting furnace may be seriously damaged and, in extreme cases, even explosive emptying of the melting unit.
  • prewarning devices of the generic type which use the principle of resistance measurement. This is based on the knowledge that the electrical resistance between any two contact points of the ceramic furnace lining, for example on the outside, is dependent on the temperature, since it drops considerably with increasing temperature, by a few powers of ten in the high-resistance range. If there is a breakthrough in the wall of the furnace lining, a local temperature increase takes place, which can be determined with a suitable distribution of the electrodes on the furnace lining and on its outer wall via the resistance measurement. The problem lies in being able to arrange the electrode network on the outside of the ceramic furnace lining with a sufficiently close mesh in order to be able to achieve a reliable early warning of the melt breakthrough that is imminent.
  • the electrode network is arranged in grooves on the outside of a so-called finished crucible, which is inserted into an induction furnace as a prefabricated part and is surrounded there with a ceramic back-ramming compound in order to fill the necessary annular gap towards the inductor wall.
  • the electrode network is located at a sufficient distance from the inductor wall in order to be able to signal an impending breakthrough point in good time without the inductor being damaged.
  • the use of ready-made crucibles is very low, because conventional furnace delivery is preferred in which the furnace lining is built up from the ceramic material at the place of use.
  • the invention has for its object to provide a pre-warning device of the type mentioned, which allows easy attachment of the electrodes in the outside of the furnace lining and ensures high display security of the entire system.
  • This task is the prewarning device Generic type according to the invention solved in that at least one of the electrodes is arranged as an electrode network on one side on a ceramic film.
  • This ceramic film is arranged either with the side provided with the electrode network or with the side facing away from the furnace lining.
  • the film has a lower thermal conductivity and a lower electrical conductivity and in the second case an approximately the same or higher thermal conductivity and an approximately the same or higher electrical conductivity compared to the ceramic material of the furnace lining.
  • the arrangement of the electrode network on the ceramic film is crucial.
  • the ceramic film with the applied electrode network is prefabricated for the respective application and can be used regardless of whether the ceramic furnace lining is built up in a conventional delivery in the melting furnace, such as an induction melting furnace, or is introduced into the furnace as a finished crucible becomes.
  • the ceramic film with the integrated electrode network can easily be attached in an equidistant arrangement to the inductor wall in an induction melting furnace, and it can also take on the role of a thermal barrier coating.
  • a ceramic Foil material is preferably a fine, felt-like non-woven fabric made of ceramic material, as is known per se and roughly comparable in mechanical properties to a stiff, rigid paper or cardboard web.
  • the ceramic foil material has a behavior which does that the furnace lining is similar. If, on the other hand, the electrode network is arranged between the ceramic foil material and the ceramic furnace lining, the thermal resistance and the electrical resistance of the foil material must be higher, expediently much higher than that of the furnace lining.
  • a particularly advantageous development of the invention is to arrange the electrode network between two such ceramic foils, of which the foil to be arranged adjacent to the outside of the furnace lining has approximately the same or higher thermal conductivity and a lower specific resistance and that on the furnace lining foil to be arranged on the opposite side have a lower thermal conductivity and a higher specific resistance than the ceramic material of the furnace lining.
  • the thermal and electrical insulation properties of the ceramic film which has the higher resistance values make it possible it even saves a separate insulation layer, which is usually provided in an induction melting furnace between the inductor wall and the ceramic furnace lining.
  • the induction melting furnace shown in FIG. 1 shows a melting chamber 1 which, apart from an upper opening, is completely surrounded by a furnace lining 2 which consists of a sinterable, ceramic material.
  • a furnace lining 2 which consists of a sinterable, ceramic material.
  • an intermediate layer 3 adjoins the furnace lining 2 radially outward, into which an electrode network 7 is embedded, whereupon will be discussed in more detail below.
  • the intermediate layer is further surrounded on the outside by a coil compensation mass 4, behind which an induction coil 5 and a magnetic conductor 6 in the form of a yoke lie further radially outwards.
  • the peculiarity of such an induction melting furnace lies in the formation of the intermediate layer 3 between the ceramic furnace lining 2 and the coil compensating mass 4, because this intermediate layer 3 both takes on an insulating function and also has the electrode network 7 mentioned, which forms an electrical monitoring system for timely signaling of breakthroughs of metal melts heard through the ceramic furnace lining 2.
  • This electrode network 7 extends over the entire circumference along the outside of the ceramic furnace lining 2, as will be explained below with reference to the processing according to FIG. 4.
  • the intermediate layer 3 consists of one or more pre-assembled components, which is described below with reference to FIG. 3.
  • the intermediate layer 3 is composed of a plurality of prefabricated ceramic mats 8, each of which extends over the height of the furnace lining 2.
  • a ceramic mat 8 is shown in Fig. 3, it is such a prefabricated component that is adapted to the particular type of furnace for which it is to be used. It has an inner Film 9 and an outer film 10, both of which have, for example, a felt-like structure made of ceramic fibers. Both foils 9 and 10 have approximately the strength and the bendability of cardboard, so they can be adapted in their composite to the inner curvature of the furnace wall, which is formed by the coil compensation mass 4 (FIGS. 1 and 2) without being advanced.
  • the films 9 and 10 can therefore also be called a web material because they can be cut to length from longer webs of the ceramic material.
  • the electrical monitoring system is based on the principle of measuring the resistance of the ceramic furnace lining 2 between two electrodes 11, which, in a plurality or multiplicity in a special configuration, form the electrode network 7, which is arranged between the two ceramic foils 9 and 10. It must therefore be measured into the ceramic material of the furnace lining 2 from the mat 8 in the installed position on the outside of the furnace lining 2. Therefore, the film 9 lying directly on the furnace lining 2 has electrical conductivity and thermal conductivity properties which correspond to or are at least similar to those of the furnace lining 2. In contrast, the outer film 10 lying away from the furnace lining 2 in the installed position has insulating properties, ie it has a much lower electrical conductivity and thermal conductivity than the inner film 9.
  • the specific resistances of the foils 9 and 10 required in relation to the ceramic material of the furnace lining 2 can be set by suitable supplements, which are added to the ceramic material of the foils 9 and 10.
  • the electrodes 11 of the electrode network 7 consist of a material which has a high resistance to temperature changes, a high heat resistance and good corrosion resistance; austenitic electrode wires are suitable for this.
  • the electrodes 11 are assigned to a first group 12 and a second group 13, the electrodes 11, which are adjacent to one another, belong to the different groups 12 and 13 and are arranged equidistantly relative to one another. Therefore, the electrodes 11 of the two groups 12 and 13 form opposing comb-like structures which interlock in the direction of the comb teeth, so that one electrode 11 of one group 12 is adjacent to electrodes 11 of the other group 13.
  • This entire electrode network 7 is located between the two foils 9 and 10, which are connected to one another in a suitable manner, as a result of which the electrode network 7 is also fixed.
  • feed lines 14 and 15 are led out at a suitable point, which are connected to one of the electrode groups 12 and 13, which are subjected to different polarities during operation.
  • the mats 8 are arranged circumferentially around the furnace lining 2.
  • the mats 8 are along the through the ceramic Streak 4 formed inner wall of the inductor as an intermediate layer 3 (Fig. 1 and 2) before delivery of the furnace lining 2.
  • the height of the furnace lining to be monitored, that is to say to be covered by the mats 8, is indicated by arrow A and the corresponding extent by arrow B. So that breakthrough monitoring is partially possible for each of the mats 8, the respective one supply line of a mat 8 is electrically connected to a separate input of an evaluation unit 16, while the other supply lines of the mats 8 are at a base potential.
  • each of these mats 8 forms a monitoring segment for itself, so that a developing melt breakthrough along the circumference of the furnace lining can be indicated by the evaluation unit 16 in relation to zones or segments. This makes it possible to localize the impending fault.
  • the mats 8 can also be separated from one another in the vertical direction if it is desired to locate the impending fault location in the vertical direction of the furnace lining.
  • the two groups 12, 13 of the electrode network 7 are acted upon by a sinusoidal AC voltage, the frequency of which is between 20 and 30 Hz.
  • This frequency range has proven to be the one with the least interference due to harmonic effects, stray effects and due to the usual mains frequency of 50 Hz and the frequencies with which the inductor of an induction melting furnace is operated Switching overvoltages occur.
  • This is also related to the complexity of the electrical resistances which lie between the electrodes 11 of the two groups 12 and 13 of the electrode network 7 and which have a capacitive component which is also caused by the respective mat 8 in which the electrode network 7 in question is embedded is. Error indications caused by a DC measuring voltage, which are caused by polarization phenomena in the material of the furnace lining, are avoided by the mentioned measuring AC voltage.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Furnace Details (AREA)
  • Crucibles And Fluidized-Bed Furnaces (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Emergency Alarm Devices (AREA)
EP92108661A 1991-06-19 1992-05-22 Vorwarneinrichtung für Induktionsschmelzöfen Expired - Lifetime EP0519231B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4120205 1991-06-19
DE4120205A DE4120205A1 (de) 1991-06-19 1991-06-19 Vorwarneinrichtung fuer induktionsschmelzoefen

Publications (3)

Publication Number Publication Date
EP0519231A2 EP0519231A2 (de) 1992-12-23
EP0519231A3 EP0519231A3 (en) 1993-01-13
EP0519231B1 true EP0519231B1 (de) 1995-03-01

Family

ID=6434279

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92108661A Expired - Lifetime EP0519231B1 (de) 1991-06-19 1992-05-22 Vorwarneinrichtung für Induktionsschmelzöfen

Country Status (10)

Country Link
US (1) US5319671A (pl)
EP (1) EP0519231B1 (pl)
JP (1) JP3305359B2 (pl)
AT (1) ATE119268T1 (pl)
CZ (1) CZ285114B6 (pl)
DE (2) DE4120205A1 (pl)
HK (1) HK1000923A1 (pl)
HU (1) HU215627B (pl)
PL (1) PL169101B1 (pl)
SK (1) SK187092A3 (pl)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4322463A1 (de) * 1993-07-06 1995-01-12 Leybold Durferrit Gmbh Vorwarneinrichtung für Induktionsschmelzöfen
DE19602249A1 (de) * 1996-01-23 1997-07-24 Ald Vacuum Techn Gmbh Vorwarneinrichtung für Induktionsschmelzöfen
US6148018A (en) * 1997-10-29 2000-11-14 Ajax Magnethermic Corporation Heat flow sensing system for an induction furnace
FR2780135B1 (fr) 1998-06-18 2000-08-25 Philec Sa Protection thermique formant bouclier thermique
WO2004015349A2 (en) * 2002-08-06 2004-02-19 Lios Technology Gmbh Furnace, method and monitoring system for monitoring its condition
DE10237603B4 (de) 2002-08-16 2008-06-19 Wieland-Werke Ag Überwachungseinrichtung für Schmelzöfen und Schmelzofen mit Überwachungseinrichtung
DE10244826B4 (de) * 2002-09-26 2012-06-28 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Anordnung zur Überwachung des Verschleißzustandes der Feuerfestauskleidung von Schmelzwannen, insbesondere von Glasschmelzwannen
DE10320821A1 (de) * 2003-05-08 2004-11-25 Saveway Gmbh & Co. Kg Feuerfestes Bauteil aus Keramikmaterial
RU2320945C2 (ru) * 2005-08-08 2008-03-27 Закрытое акционерное общество "Электроника силовая" Способ контроля состояния футеровки индукционной плавильной печи
DE102006006524B4 (de) * 2006-02-10 2008-11-27 Saveway Gmbh & Co. Kg Verfahren zur Überwachung eines Induktionsofens und Induktionsofen
GB2458964A (en) * 2008-04-04 2009-10-07 Elmelin Plc Induction furnace lining
DE102009033502B4 (de) * 2009-07-15 2016-03-03 Schott Ag Verfahren und Vorrichtung zur Herstellung von Glasprodukten aus einer Glasschmelze
CA2837074A1 (en) 2011-05-23 2012-11-29 Inductotherm Corp. Electric induction furnace with lining wear detection system
US10598439B2 (en) 2011-05-23 2020-03-24 Inductotherm Corp. Electric induction furnace lining wear detection system
EP3488167B1 (en) * 2016-07-25 2020-11-25 Inductotherm Corp. Electric induction furnace with lining wear detection system
FR3084662B1 (fr) * 2018-08-01 2022-06-24 Saint Gobain Ct Recherches Detecteur d'usure pour four de verrerie
DE102019209389A1 (de) * 2019-06-27 2020-12-31 Fraunhofer Gesellschaft zur Förderung der angewandten Forschung e.V. Anordnung für den Niederdruckguss von hochschmelzenden Metallen
DE102021133072A1 (de) 2020-12-14 2022-06-15 Peter Schmidt Verfahren zur Messung des Verschleißzustandes von Induktionstiegelöfen
FR3123975B1 (fr) * 2021-06-09 2026-03-20 Saint Gobain Ct Recherches Plaque instrumentee pour four

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1922029A (en) * 1931-07-22 1933-08-15 Ajax Electrothermic Corp Protective device for induction furnace
DE1208451B (de) * 1961-05-17 1966-01-05 Bbc Brown Boveri & Cie Vorrichtung zur Signalisierung entstehender Schmelztiegeldurchbrueche bei Induktionschmelzoefen
DE1199930B (de) * 1962-10-11 1965-09-02 Bbc Brown Boveri & Cie Vorrichtung zur Signalisierung entstehender Schmelztiegeldurchbrueche
DE1220086B (de) * 1965-07-08 1966-06-30 Bbc Brown Boveri & Cie Vorrichtung zur Anzeige beginnender und zur Verhuetung vollstaendiger Schmelztiegeldurchbrueche
DE2718016C2 (de) * 1977-04-22 1984-02-23 Dmitrij Abramovič Gitgarc Verfahren zur Zustandsüberwachung des Futters eines Schmelzaggregats und Einrichtung zu dessen Durchführung
US4201882A (en) * 1978-05-05 1980-05-06 Apatova Larisa D Induction melting furnace
FR2427569A1 (fr) * 1978-05-30 1979-12-28 Kolotilo Daniil Four a induction
JPH0781785B2 (ja) * 1989-03-13 1995-09-06 富士電機株式会社 誘導加熱による金属溶湯炉

Also Published As

Publication number Publication date
DE59201510D1 (de) 1995-04-06
EP0519231A2 (de) 1992-12-23
US5319671A (en) 1994-06-07
HUT62698A (en) 1993-05-28
PL294910A1 (pl) 1993-02-08
PL169101B1 (pl) 1996-06-28
EP0519231A3 (en) 1993-01-13
SK187092A3 (en) 1995-06-07
HU9201919D0 (en) 1992-09-28
ATE119268T1 (de) 1995-03-15
HU215627B (hu) 1999-01-28
HK1000923A1 (en) 1998-05-08
CZ187092A3 (en) 1993-01-13
DE4120205A1 (de) 1992-12-24
JP3305359B2 (ja) 2002-07-22
CZ285114B6 (cs) 1999-05-12
JPH05180583A (ja) 1993-07-23

Similar Documents

Publication Publication Date Title
EP0519231A2 (de) Vorwarneinrichtung für Induktionsschmelzöfen
EP3197241B1 (de) Heizeinrichtung und verfahren zur temperaturmessung an der heizeinrichtung
EP1818638B1 (de) Verfahren zur Überwachung eines Induktionsofens und Induktionsofen
DE69732165T2 (de) Induktionsschmelzofen mit kaltem Tiegel
DE3503221A1 (de) Feuerfester gasdurchlaessiger stein
DE102017205886A1 (de) Vorrichtung mit Verschleißteil und Messeinrichtung für Verschleiß
DE4329509A1 (de) Brückenbildungsschutzvorrichtung für Induktionsöfen
DE2817869C3 (de) Deckel für einen Elektrolichtbogenofen
DE10237603B4 (de) Überwachungseinrichtung für Schmelzöfen und Schmelzofen mit Überwachungseinrichtung
EP1601235A2 (de) Überwachungseinrichtung für flexible Heizelemente
EP0541019A1 (de) Verfahren und Einrichtung zur Überwachung der Wandstärke eines keramischen Tiegels eines Induktionstiegelofens
CH665614A5 (de) Verbundfolie zum auskleiden von fluessigkeitsbehaeltern.
DE714365C (de) Kondensator, dessen Metallbelag so duenn ist, dass er bei einem Durchschlag an oder in der Naehe der Durchschlagsstelle wegbrennt
DE69811889T2 (de) Rinneninduktor
DE4322463A1 (de) Vorwarneinrichtung für Induktionsschmelzöfen
EP0005838A1 (de) Induktionstiegelofen
DE2560645C2 (de) Leitwertmeßsonde zum Messen des Pegels einer in einem Behälter befindlichen Flüssigkeit
EP0276206B1 (de) Kontaktschiene für elektrischen fadenwächter
DE202008009317U1 (de) Dichtungsanordnung für eine Flanschverbindung
DE1807641B2 (de) Fuehler fuer die waermemeldung
AT508538B1 (de) Wärmetauscher
DE19602249A1 (de) Vorwarneinrichtung für Induktionsschmelzöfen
EP3839319B1 (de) Elektroschweissband, verwendung und verfahren
DE4136917C1 (pl)
EP0110817A1 (de) Einrichtung zum Ermitteln der Lage des Giessspiegels

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

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A2

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

AK Designated contracting states

Kind code of ref document: A3

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

17P Request for examination filed

Effective date: 19930713

17Q First examination report despatched

Effective date: 19940816

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 ES FR GB IT LI NL SE

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

Ref country code: NL

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: 19950301

Ref country code: ES

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19950301

Ref country code: BE

Effective date: 19950301

REF Corresponds to:

Ref document number: 119268

Country of ref document: AT

Date of ref document: 19950315

Kind code of ref document: T

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

Effective date: 19950224

REF Corresponds to:

Ref document number: 59201510

Country of ref document: DE

Date of ref document: 19950406

ITF It: translation for a ep patent filed
ET Fr: translation filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Effective date: 19950522

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

Ref country code: LI

Effective date: 19950531

Ref country code: CH

Effective date: 19950531

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

Ref country code: SE

Effective date: 19950601

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
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

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

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

Ref country code: FR

Payment date: 20110524

Year of fee payment: 20

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

Ref country code: GB

Payment date: 20110506

Year of fee payment: 20

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

Ref country code: IT

Payment date: 20110524

Year of fee payment: 20

Ref country code: DE

Payment date: 20110504

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59201510

Country of ref document: DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59201510

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20120521

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 EXPIRATION OF PROTECTION

Effective date: 20120523

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 EXPIRATION OF PROTECTION

Effective date: 20120521