EP0473809B1 - Gleichstrom-Lichtbogenofen - Google Patents

Gleichstrom-Lichtbogenofen Download PDF

Info

Publication number
EP0473809B1
EP0473809B1 EP90116866A EP90116866A EP0473809B1 EP 0473809 B1 EP0473809 B1 EP 0473809B1 EP 90116866 A EP90116866 A EP 90116866A EP 90116866 A EP90116866 A EP 90116866A EP 0473809 B1 EP0473809 B1 EP 0473809B1
Authority
EP
European Patent Office
Prior art keywords
lining layer
arc
arc furnace
sector
possesses
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
EP90116866A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0473809A1 (de
Inventor
Sven-Einar Stenkvist
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.)
ABB Asea Brown Boveri Ltd
Original Assignee
ABB Asea Brown Boveri Ltd
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 ABB Asea Brown Boveri Ltd filed Critical ABB Asea Brown Boveri Ltd
Priority to AT90116866T priority Critical patent/ATE93114T1/de
Priority to DE9090116866T priority patent/DE59002344D1/de
Priority to EP90116866A priority patent/EP0473809B1/de
Priority to ES90116866T priority patent/ES2044352T3/es
Priority to SU915001250A priority patent/RU2013730C1/ru
Priority to US07/748,866 priority patent/US5237585A/en
Priority to CA002049853A priority patent/CA2049853A1/en
Priority to ZA916844A priority patent/ZA916844B/xx
Priority to BR919103756A priority patent/BR9103756A/pt
Priority to JP3221355A priority patent/JPH04233191A/ja
Priority to CN91108582A priority patent/CN1027314C/zh
Priority to KR1019910015354A priority patent/KR920007498A/ko
Publication of EP0473809A1 publication Critical patent/EP0473809A1/de
Application granted granted Critical
Publication of EP0473809B1 publication Critical patent/EP0473809B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B7/00—Heating by electric discharge
    • 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
    • F27D11/00—Arrangement of elements for electric heating in or on furnaces
    • F27D11/08—Heating by electric discharge, e.g. arc discharge
    • F27D11/10—Disposition of electrodes
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B7/00—Heating by electric discharge
    • H05B7/02—Details
    • H05B7/06—Electrodes

Definitions

  • the invention relates to a direct current arc furnace with a furnace vessel which is surrounded by a metallic jacket, with at least one electrode connected as a cathode and at least one bottom contact, the bottom of the furnace consisting of a single or multi-layer lining layer which is electrically conductive Brick or other inserts with the same effect, which lining layer rests on a contact plate covering most of the bottom, which contact plate forms the ground contact switched as an anode and rests on a bottom plate, said contact plate is provided with a plurality of connection fittings, which are provided by openings reach through in the base plate and are connected via electrical lines to a power supply device provided next to the furnace vessel.
  • the invention relates to a state of the art, as it results, for example, from US Pat. No. 4,550,413.
  • the arc can be "centered" by special guiding of the power supply and discharge lines under and next to the furnace vessel. It is proposed in US-A-4,550,413 and US-A-4,577,326 to lay these lines in such a way that the magnetic fields caused by the flowing direct current act symmetrically on the arc.
  • these measures are complex and also increase the costs of the furnace.
  • Another solution is to make the electrode, including the electrode holder, horizontally displaceable relative to the furnace vessel, in order to compensate for asymmetries in the current supply and dissipation. This measure is also very complex because there must be sufficient space in the furnace cover for the travel of the electrode.
  • the invention has for its object to provide a DC arc furnace in which a targeted deflection and / or symmetry of the arc is achieved with simple means.
  • this object is achieved in that one or more sections of the lining layer consist of a material for the targeted deflection of the arc has a lower specific electrical conductivity than the lining layer in the rest of the section.
  • the lining layer in its section facing the power supply device preferably consists at least partially of a material which has a lower specific electrical conductivity than the lining layer in the rest of the section.
  • the lining layer in the area of the floor cut has a lower electrical conductivity than in the rest of the area, in order in this way to avoid a deflection of the arc. In this way, the arc is deflected in the direction of the floor tapping and thus more heat is introduced into the melt.
  • deflection of the arc can be accomplished if the lining layer in the area in which charging is carried out has a lower specific electrical conductivity than in the rest of the area. Analogous to the aforementioned, this leads to deflection of the arc towards charging and thus to an increased supply of heat.
  • the advantage of the invention is to be seen in particular in the fact that without complex wiring under or next to the furnace vessel or method of the electrode for the targeted deflection of the arc, this deflection, if necessary, leading to symmetry, or deliberately deflection of the arc in a predetermined direction . Since the lining layer has to be renewed at regular intervals anyway, existing arc furnaces can also be equipped with the lining layer according to the invention.
  • a direct current arc furnace according to FIG. 1 has a furnace vessel 1 which is provided with a jacket 2 made of metal.
  • the furnace lid and the electrode holder are omitted been.
  • the furnace has only one solid electrode 3 connected as a cathode, but this number can also be two, three or more.
  • An electrode spot, ie a slag-free surface of the melt 4 is obtained under the electrode 3 in the usual way.
  • the furnace has a tapping device in the form of an eccentric bottom cut 5 in an oriel-like projection 6 of the furnace vessel. There is contact with the floor in the bottom of the furnace.
  • the ground contact consists in the example of three lining layers 7a, 7b and 7c graphite or graphite-containing bricks 8a, 8b, 8c, which rest on a dome-shaped contact plate 9.
  • Connection fittings 10 (FIG. 1a) on the contact plate 9 project downwards through openings 11 in the vessel bottom 12 into the open.
  • the conventional furnace lining 13 adjoins the floor lining layer on the outside.
  • the vessel bottom 12 can be provided with a cooling device (not shown) in order to keep it at the lowest possible temperature.
  • the bricks 8a, 8b and 8c of the lining layers 7a, 7b and 7c serve as current conductors between the melt 14 and the contact plate 9.
  • the direct current arc furnace corresponds to the prior art and is described in detail, for example, in US Pat. No. 4,228,314, DE Pat. No. 30 22 566, GB-A 21 33 125 or DE-A-32 41 987, wherein the first-mentioned documents relate to classic arc furnaces, the latter-mentioned arc furnaces with eccentric floor tapping.
  • the jacket 2 of the furnace vessel is drawn radially inwards and forms an inwardly projecting collar 15, the end 16 of which is bent upwards.
  • the base plate 12 projects beyond the collar 15 in the radial direction.
  • a ring 17 made of insulating material is arranged in the overlap area. In this way, the entire bottom part of the furnace is supported on the collar 15 in an electrically insulated manner. The bottom part of the furnace virtually floats in the furnace vessel 1. At the same time, the electrical insulation between the furnace shell 2 and the base plate 12 and thus the ground contact is brought about via the insulating material.
  • connection fittings 9 can be seen from the top view of the underside of the furnace vessel 1 according to FIG. One recognizes four fittings 10 regularly distributed over the floor and the high-current lines 18 to the power supply device 19 of the arc furnace.
  • the top view of the upper lining layer 7a according to FIG. 3 shows the distribution of the bricks 8a: in a first sector 21 with an opening angle ⁇ of typically 45 ° to 90 °, which opens symmetrically towards the power supply device 12, the bricks 8a exist, 8b and / or 8c of the lining layers 7a, 7b and 7c made of a material with a lower carbon content than the bricks of the second sector 22, which typically have a carbon content of 10-20% by weight carbon.
  • the electrical conductivity in the first sector 21 is accordingly lower than outside this area.
  • bricks can also be used which have electrical conductors other than graphite, e.g. those in which the electrical conductivity is determined by the boride content.
  • Bricks can also be used which consist of a substantially non-conductive core which is completely or only partially covered with a metallic shell.
  • the said lining layers can also be designed differently in terms of their electrical conductivity in another way, for example by adding bricks to the lining layer (s) in the section of the lining layer which faces the power supply device (12) lower conductivity or non-conductive bricks are interspersed.
  • a second sector 23 with bricks that are less electrically conductive is provided, which sector opens symmetrically with an opening angle ⁇ toward the floor cut 5.
  • the same considerations apply to the dimensioning of the opening angle ⁇ and the conductivity of the bricks as were mentioned above in connection with the symmetrization.
  • the targeted deflection due to the construction of the sector 23 can also be used on its own if, for example, a line guide according to the prior art according to US Pat. No. 4,577,326 or US Pat. No. 4,550,413 is used.
  • FIG. 3 also indicates a third possibility of influencing the arc. It applies to arc furnaces with continuous charging with sponge iron pellets or scrap.
  • a deflection in the direction of the batch is achieved in that in a sector 25 with the opening angle ⁇ the material of the lining layer has a lower conductivity than in the section (s) 22.
  • this measure can be taken on its own if necessary.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Discharge Heating (AREA)
  • Furnace Details (AREA)
EP90116866A 1990-09-03 1990-09-03 Gleichstrom-Lichtbogenofen Expired - Lifetime EP0473809B1 (de)

Priority Applications (12)

Application Number Priority Date Filing Date Title
AT90116866T ATE93114T1 (de) 1990-09-03 1990-09-03 Gleichstrom-lichtbogenofen.
DE9090116866T DE59002344D1 (de) 1990-09-03 1990-09-03 Gleichstrom-lichtbogenofen.
EP90116866A EP0473809B1 (de) 1990-09-03 1990-09-03 Gleichstrom-Lichtbogenofen
ES90116866T ES2044352T3 (es) 1990-09-03 1990-09-03 Horno de arco electrico de corriente continua.
SU915001250A RU2013730C1 (ru) 1990-09-03 1991-08-21 Дуговая печь постоянного тока
US07/748,866 US5237585A (en) 1990-09-03 1991-08-23 Direct-current arc furnace having circumferential zones of varying conductivity
CA002049853A CA2049853A1 (en) 1990-09-03 1991-08-26 Direct-current arc furnace
ZA916844A ZA916844B (en) 1990-09-03 1991-08-29 Direct-current arc furnace
BR919103756A BR9103756A (pt) 1990-09-03 1991-08-30 Forno de arco voltaico de corrente continua
JP3221355A JPH04233191A (ja) 1990-09-03 1991-09-02 直流アーク炉
CN91108582A CN1027314C (zh) 1990-09-03 1991-09-02 直流电弧炉
KR1019910015354A KR920007498A (ko) 1990-09-03 1991-09-03 직류 아크로

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP90116866A EP0473809B1 (de) 1990-09-03 1990-09-03 Gleichstrom-Lichtbogenofen

Publications (2)

Publication Number Publication Date
EP0473809A1 EP0473809A1 (de) 1992-03-11
EP0473809B1 true EP0473809B1 (de) 1993-08-11

Family

ID=8204419

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90116866A Expired - Lifetime EP0473809B1 (de) 1990-09-03 1990-09-03 Gleichstrom-Lichtbogenofen

Country Status (12)

Country Link
US (1) US5237585A (xx)
EP (1) EP0473809B1 (xx)
JP (1) JPH04233191A (xx)
KR (1) KR920007498A (xx)
CN (1) CN1027314C (xx)
AT (1) ATE93114T1 (xx)
BR (1) BR9103756A (xx)
CA (1) CA2049853A1 (xx)
DE (1) DE59002344D1 (xx)
ES (1) ES2044352T3 (xx)
RU (1) RU2013730C1 (xx)
ZA (1) ZA916844B (xx)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH682280A5 (xx) * 1991-06-14 1993-08-13 Asea Brown Boveri
DE4129756C2 (de) * 1991-09-04 1995-06-29 Mannesmann Ag Metallurgisches Gefäß für eine Gleichstromlichtbogeneinrichtung
DE69320564T2 (de) * 1992-07-31 1999-04-29 Danieli & C. Officine Meccaniche S.P.A., Buttrio, Udine Gleichstromlichtbogenofen mit Steuerung der Lichtbogenablenkung
DE4240891C2 (de) * 1992-12-04 1995-11-16 Voest Alpine Ind Anlagen Gleichstrom-Lichtbogenofen und Verfahren zu dessen Betreibung
US5867523A (en) * 1996-05-28 1999-02-02 Hatch Associates Ltd. Electric furnace with conductive hearth
CN1045475C (zh) * 1996-06-21 1999-10-06 宝山钢铁(集团)公司 直流电弧炉通过倾动顶电极控制偏弧的方法
US5999557A (en) * 1998-06-19 1999-12-07 The Broken Hill Proprietary Company Steel making bath control
KR100341319B1 (ko) * 1999-12-30 2002-06-22 김형배 수석가공장치
DE10049959B4 (de) * 2000-10-10 2005-10-06 Georgsmarienhütte Gmbh Elektroofen für die Stahlherstellung
WO2006024149A1 (en) 2004-09-01 2006-03-09 Hatch Ltd. System and method for minimizing loss of electrical conduction during input of feed material to a furnace
US20080056327A1 (en) * 2006-08-30 2008-03-06 Hatch Ltd. Method and system for predictive electrode lowering in a furnace
CN101786619B (zh) * 2010-02-10 2012-03-28 黎应和 竖式高温连续石墨化炉
CN109964538B (zh) * 2016-11-15 2021-12-24 奥图泰(芬兰)公司 用于控制电弧炉中的电弧的方法和电弧炉
CN110081702B (zh) * 2019-05-14 2020-08-11 中冶赛迪工程技术股份有限公司 一种抑制直流电弧炉偏弧方法

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL8001669A (nl) * 1980-03-21 1981-10-16 Estel Hoogovens Bv Vuurvaste constructie van de bodem en het aansluitende haardgedeelte van een schachtoven.
SE452542B (sv) * 1983-04-21 1987-11-30 Asea Ab Likstroms-ljusbagsugn
DE3413745C2 (de) * 1983-04-21 1994-03-03 Asea Ab Gleichstromlichtbogenofen
SE452690B (sv) * 1983-07-07 1987-12-07 Asea Ab Likstroms-ljusbagsugn
ATE34901T1 (de) * 1984-01-31 1988-06-15 Bbc Brown Boveri & Cie Bodenelektrode fuer einen gleichstromlichtbogenofen.
DE3534750A1 (de) * 1985-09-28 1987-04-16 Krupp Gmbh Boden eines elektrisch beheizten schmelzofens, insbesondere eines gleichstromofens
FR2602320B1 (fr) * 1986-08-01 1989-12-29 Clecim Sa Procede de fusion de ferraille et four electrique pour la mise en oeuvre du procede
FR2602318B1 (fr) * 1986-08-01 1988-11-10 Clecim Sa Four a arc alimente a partir d'une source de courant continu pour la fusion continue de ferrailles
US5173920A (en) * 1989-08-21 1992-12-22 Asea Brown Boveri Ltd. Direct-current electric-arc furnace
US5052018A (en) * 1989-10-12 1991-09-24 Deutsche Voest-Alpine Industrieanlagen Gmbh Anode for a direct current arc furnace
CH680086A5 (xx) * 1990-05-09 1992-06-15 Asea Brown Boveri

Also Published As

Publication number Publication date
EP0473809A1 (de) 1992-03-11
JPH04233191A (ja) 1992-08-21
RU2013730C1 (ru) 1994-05-30
ZA916844B (en) 1992-05-27
US5237585A (en) 1993-08-17
CA2049853A1 (en) 1992-03-04
ATE93114T1 (de) 1993-08-15
DE59002344D1 (de) 1993-09-16
KR920007498A (ko) 1992-04-28
CN1027314C (zh) 1995-01-04
ES2044352T3 (es) 1994-01-01
BR9103756A (pt) 1992-05-19
CN1059594A (zh) 1992-03-18

Similar Documents

Publication Publication Date Title
EP0473809B1 (de) Gleichstrom-Lichtbogenofen
EP0010305B1 (de) Flüssigkeitsgekühlte Halterung für eine Elektrodenspitze
DE3107454C2 (xx)
DE69111720T3 (de) Mit gleichstrom betriebener ofen zum schmelzen von metall.
DE2510326A1 (de) Lichtbogenofen
DE69931980T2 (de) Elektrischer Strahlungsheizkörper
EP0151415B1 (de) Gleichstrom-Lichtbogenofen oder Gleichstrom-Lichtbogenpfanne
EP0518070B1 (de) Gleichstrom-Lichtbogenofenanlage
EP0587651B1 (de) Gleichstromlichtbogenofen
EP0541044A2 (de) Gleichstrom-Lichtbogenofen
DE3242209C2 (xx)
EP0753077B1 (de) Gleichstrombeheiztes metallurgisches gefäss mit bodenelektrode
DE3400186A1 (de) Durchfuehrung fuer elektroden in einem ofendeckel eines elektrolichtbogen- oder reduktionsofens
DE2847946C2 (de) Gleichstromgespeister Lichtbogenofen
EP0519319A1 (de) Verfahren zum Betrieb eines Gleichstrom-Lichtbogenofens
DE3825984C2 (xx)
DE4129756C2 (de) Metallurgisches Gefäß für eine Gleichstromlichtbogeneinrichtung
EP0273975B1 (de) Plasma-induktionsofen
EP0413970B1 (de) Gleichstromlichtbogenofen
EP1911329A1 (de) Transformatorsystem für elektrische lichtbogenöfen mit drei elektroden
DE4225256C2 (de) Mit Gleichstrom betriebene Ofenanlage
DE1240629B (de) Rinnenofen
DE4126627A1 (de) Anode fuer einen gleichstrom-lichtbogenofen
EP0793732B1 (de) Gleichstrom-lichtbogenofen mit zwei oder mehr elektroden
DE2946588A1 (de) Dreiphasen-lichtbogenschmelz- oder reduktionsofen

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

RBV Designated contracting states (corrected)

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

17P Request for examination filed

Effective date: 19920810

17Q First examination report despatched

Effective date: 19930128

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 LU NL SE

REF Corresponds to:

Ref document number: 93114

Country of ref document: AT

Date of ref document: 19930815

Kind code of ref document: T

REF Corresponds to:

Ref document number: 59002344

Country of ref document: DE

Date of ref document: 19930916

ITF It: translation for a ep patent filed
ET Fr: translation filed
GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19931021

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

Ref country code: CH

Payment date: 19931210

Year of fee payment: 4

EPTA Lu: last paid annual fee
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2044352

Country of ref document: ES

Kind code of ref document: T3

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

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

Ref country code: LU

Payment date: 19940801

Year of fee payment: 5

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19940815

Year of fee payment: 5

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

Ref country code: BE

Payment date: 19940825

Year of fee payment: 5

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

Ref country code: ES

Payment date: 19940915

Year of fee payment: 5

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

Ref country code: LI

Effective date: 19940930

Ref country code: CH

Effective date: 19940930

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

Ref country code: NL

Payment date: 19940930

Year of fee payment: 5

EAL Se: european patent in force in sweden

Ref document number: 90116866.6

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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: 19950903

Ref country code: GB

Effective date: 19950903

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 THE APPLICANT RENOUNCES

Effective date: 19950904

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

Ref country code: BE

Effective date: 19950930

BERE Be: lapsed

Owner name: ASEA BROWN BOVERI A.G.

Effective date: 19950930

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

Ref country code: NL

Effective date: 19960401

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

Effective date: 19950903

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 19960401

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

Ref country code: SE

Payment date: 19960819

Year of fee payment: 7

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

Ref country code: AT

Payment date: 19960821

Year of fee payment: 7

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

Ref country code: FR

Payment date: 19960827

Year of fee payment: 7

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

Ref country code: DE

Payment date: 19960917

Year of fee payment: 7

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

Ref country code: AT

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

Effective date: 19970903

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

Ref country code: SE

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

Effective date: 19970904

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

Ref country code: FR

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

Effective date: 19970930

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

Ref country code: DE

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

Effective date: 19980603

EUG Se: european patent has lapsed

Ref document number: 90116866.6

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 19991007

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

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050903