[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

EP0568271B1 - Câbles d'acier pour le renforcement des articles en caoutchouc et des bandages pneumatiques radiaux - Google Patents

Câbles d'acier pour le renforcement des articles en caoutchouc et des bandages pneumatiques radiaux Download PDF

Info

Publication number
EP0568271B1
EP0568271B1 EP19930303148 EP93303148A EP0568271B1 EP 0568271 B1 EP0568271 B1 EP 0568271B1 EP 19930303148 EP19930303148 EP 19930303148 EP 93303148 A EP93303148 A EP 93303148A EP 0568271 B1 EP0568271 B1 EP 0568271B1
Authority
EP
European Patent Office
Prior art keywords
steel
cord
filament
wrap
sheath layer
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
EP19930303148
Other languages
German (de)
English (en)
Other versions
EP0568271A1 (fr
Inventor
Yoshinori Kuriya
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.)
Bridgestone Corp
Original Assignee
Bridgestone Corp
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 Bridgestone Corp filed Critical Bridgestone Corp
Publication of EP0568271A1 publication Critical patent/EP0568271A1/fr
Application granted granted Critical
Publication of EP0568271B1 publication Critical patent/EP0568271B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B1/00—Constructional features of ropes or cables
    • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
    • D07B1/0606—Reinforcing cords for rubber or plastic articles
    • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B1/00—Constructional features of ropes or cables
    • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
    • D07B1/0606—Reinforcing cords for rubber or plastic articles
    • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
    • D07B1/0626—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration the reinforcing cords consisting of three core wires or filaments and at least one layer of outer wires or filaments, i.e. a 3+N configuration
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B1/00—Constructional features of ropes or cables
    • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
    • D07B1/0606—Reinforcing cords for rubber or plastic articles
    • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
    • D07B1/0633—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration having a multiple-layer configuration
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2023—Strands with core
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2024—Strands twisted
    • D07B2201/2029—Open winding
    • D07B2201/2031—Different twist pitch
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2015—Strands
    • D07B2201/2024—Strands twisted
    • D07B2201/2029—Open winding
    • D07B2201/2031—Different twist pitch
    • D07B2201/2032—Different twist pitch compared with the core
    • D—TEXTILES; PAPER
    • D07—ROPES; CABLES OTHER THAN ELECTRIC
    • D07B—ROPES OR CABLES IN GENERAL
    • D07B2201/00—Ropes or cables
    • D07B2201/20—Rope or cable components
    • D07B2201/2095—Auxiliary components, e.g. electric conductors or light guides
    • D07B2201/2097—Binding wires
    • D07B2201/2098—Binding wires characterized by special properties or the arrangements of the binding wire

Definitions

  • This invention relates to steel cords used as a reinforcement for rubber articles such as pneumatic tires, industrial belts and the like as well as a pneumatic radial tire comprising a carcass ply comprised of such steel cords and having improved durability.
  • tires are well-known.
  • tires for trucks and buses or for light trucks generally comprise a carcass ply using cords of two or three layer construction.
  • the tensile load of the steel cord lowers during the running of the tire because the sectional area of steel filaments constituting the steel cord is decreased by fretting.
  • the decrease of sectional area in some filaments constituting the steel cord becomes conspicuous, such filaments are apt to undergo breakage as a result of tensile shock or repetitive bending. Once these filaments are broken, tensile stress in the other filaments increases to promote fatigue breakage of the cord. Therefore, in order to increase the durability of the cord, it is required to avoid a part of the steel filaments constituting the steel cord becoming prematurely broken as compared with the remaining steel filaments, and it is desirable that the tensile loads of all filaments in the cord are equally lowered.
  • the present inventor has made studies with respect to steel cords formed by spirally winding a wrap steel filament around a steel cord of layer twisting structure for stably preventing the lowering of tensile load in the steel filaments (filament diameter: 0.15-0.25 mm) constituting the steel cord used in a carcass ply during the running of a tire, and found that the lowering of tensile load in the steel filaments constituting the outermost layer of the steel cord is extremely large and that a main factor in the lowering of tensile load is a fretting phenomenon with the wrap filament.
  • the inventor has made studies with respect to steel cords formed by removing the wrap filament, which is the main factor in the lowering of tensile load, for preventing the occurrence of fretting around the wrap filament, and confirmed that the fretting is certainly removed to control the lowering of tensile load of the steel filament, but the restraining property of the cord is poor due to the absence of the wrap filament and furthermore when the cord is excessively bent, the steel filaments constituting the cord are scattered and finally broken when abnormal force is applied to the steel filaments. In the latter case, the life at break of the cord is largely decreased as compared with the cord stabilized by wrapping the cord with the wrap filament. As a result, in order to prevent the decrease of the cord life based on the application of extreme bending force, it becomes required to restrain the cord with the steel filament in any form.
  • the inventor has made further studies with respect to the steel cord of layer twisting structure and discovered that it is advantageous to prevent the lowering of tensile load in the steel filaments of the outermost layer by controlling the application of abnormal force to the steel filament while maintaining the restraint of the filaments constituting the cord when a large bending force is applied to the cord and mitigating the fretting between the wrap filament and the steel filaments constituting the outermost layer of the cord, and as a result the invention has been accomplished.
  • a steel cord for the reinforcement of rubber articles formed by twisting 1 to 4 steel filaments as a core and at least one sheath layer comprised of a plurality of steel filaments arranged around the core, provided that the twisting pitch of at least one sheath layer is different from that of a remaining sheath layer adjacent thereto or that of the core, and wherein wrap steel filament is spirally wound around a sheath layer located at an outermost side of the steel cord in the same twisting direction as in one said sheath layer.
  • a pneumatic radial tire comprising a carcass ply of a radial structure toroidally extending between a pair of bead portions and containing steel cords therein, said steel cord being formed by twisting 1 to 4 steel filaments as a core and at least one sheath layer comprised of a plurality of steel filaments arranged around the core, provided that the twisting pitch of at least one sheath layer is different from that of a remaining sheath layer adjacent thereto or that of the core, and wherein a wrap steel filament is spirally wound around a sheath layer located at an outermost side of the steel cord in the same twisting direction as in the said sheath layer.
  • the wrap steel filament is wound around the outermost sheath layer at a twisting pitch of 2-6 mm.
  • the resistance to corrosion fatigue is improved and also the lowering of tensile load of the cord due to fretting between the outermost sheath layer and the wrap steel filament can be controlled while maintaining the restraint of the steel filaments in the cord.
  • Figs. 1 and 2 are sectionally shown embodiments of steel cord for the reinforcement of rubber articles according to the invention having layer twisting structures of 3+9+1 and 1+6+12+1, respectively.
  • numeral 1 is a core comprised of one or three steel filaments
  • numeral 2 is a sheath layer comprised of a plurality of steel filaments arranged adjacent to each other around the core 1.
  • the sheath layer 2 is comprised of nine steel filaments in Fig. 1 and six steel filaments in Fig. 2.
  • a second sheath layer 3 comprised of twelve steel filaments is arranged around the sheath layer 2 in the embodiment of Fig. 2.
  • numeral 4 is a wrap steel filament spirally wound around the outermost sheath layer in the same twisting direction as in the outermost sheath layer.
  • Fig. 3 is sectionally shown a third embodiment of the steel cord according to the invention having a layer twisting structure of 3+9+15+1, in which a second sheath layer 3 comprised of 15 steel filaments is arranged around a first sheath layer 2 comprised of 9 steel filaments.
  • a steel cord having a layer twisting structure of 3+8+13+1 may be used as a modification of this embodiment.
  • the non-uniform lowering of tensile load in the steel filaments is due to the fact that the wrap steel filament is twisted in the direction opposite to the twisting direction of the steel filaments in the outermost sheath layer. Since the twisting direction of the wrap steel filament is different from that of the steel filaments in the outermost sheath layer, the contact area therebetween becomes small and the contact pressure per unit area is large.
  • torsion is applied to the carcass ply cord at a ground contact portion of the tire in the axial direction of the cord.
  • torsional force is applied in a direction opposite to the twisting direction of the steel filaments in the outermost sheath layer, if the twisting direction of the wrap steel filament is opposite to the twisting direction of the steel filaments in the outermost sheath layer, torsional force is created in a direction of tightening the twisting direction of the wrap steel filament and hence a relative movement between the wrap steel filament and the steel filaments in the outermost sheath layer occurs.
  • the twisting direction of the spiral wrap steel filament restraining the steel cord of layer twisting structure is made in the same direction as the steel filaments of the outermost sheath layer, whereby the contact area between the steel filaments in the outermost sheath layer and the wrap steel filament is increased and the contact pressure therebetween is decreased. Further, even if torsional force is applied to the cord, the relative movement between the steel filaments in the outermost sheath layer and the wrap steel filament reduces and hence the reduction of sectional area in the steel filaments of the outermost sheath layer and the lowering of tensile load accompanied therewith are controlled.
  • the steel filaments are restrained by the wrap steel filament, even when the cord is extremely bent, the steel filaments constituting the cord are not scattered and hence the breaking life of the cord is not lowered even when abnormal force is applied to a part of the steel filaments.
  • the filament diameter may be the same or different between the core and the sheath.
  • the twisting pitch of the steel filaments in the outermost sheath layer is the same as that of the spiral wrap steel filament, there is caused movement of the wrap steel filament into the outermost sheath layer, so that it is necessary that the twisting pitch of the steel filaments in the outermost sheath layer is different from that of the wrap steel filament.
  • the invention is particularly preferable to apply the invention to a steel cord having a layer twisting structure of 3+8+1 in view of the cord durability. That is, when the invention is applied to rubber penetration type cords having a gap between the steel filaments in the sheath layer, if a large bending force is applied to the cord under a low internal pressure, the movement of the steel filaments becomes small because rubber penetrates into the inside of the cord and hence the resistance to cord breaking-up is improved.
  • Steel cords are prepared as shown in Table 1 and applied to a carcass ply of a radial tire for trucks and buses having a tire size of 11/70R22.5 14PR at an end count of 22.0 cords/5 cm.
  • the fretting depth and cord breakage under large bending force are measured by running such a tire on a drum under the following test conditions:
  • steel cord of Comparative Example 1 having a layer twisting structure of 3+9+1 and a wrap steel filament of Z-lay (control)
  • steel cord of Comparative Example 2 having a layer twisting structure of 3+9 and no wrap steel filament
  • steel cord of Example 1 having a layer twisting structure of 3+9+1 and a wrap steel filament of S-lay according to the invention.
  • the measured results are shown in Table 1.
  • the steel filaments of the outermost sheath layer corresponding to two cords are taken out from the tire after the running under usual conditions and broken through a tensile test. Then, the broken sections of these filaments are observed by means of a microscope to measure a fretting depth h shown in Fig. 4 when the section of the original steel filament is circle.
  • the fretting depth is evaluated by an index value according to the following equation:
  • Steel cords are prepared as shown in Table 2 and applied to a carcass ply of a radial tire for trucks and buses having a tire size of 11/70R22.5 14PR at an end count of 20.0 cords/5 cm.
  • the fretting depth and cord breakage under large bending force are measured in the same manner as in Example 1 by running such a tire on a drum under the same conditions as in Example 1.
  • steel cord of Comparative Example 3 having a layer twisting structure of 1+6+12+1 and a wrap steel filament of Z-lay (control)
  • steel cord of Comparative Example 4 having a layer twisting structure of 1+6+12 and no wrap steel filament
  • steel cord of Example 2 having a layer twisting structure of 1+6+12+1 and a wrap steel filament of S-lay according to the invention.
  • the measured results are shown in Table 2.
  • the twisting pitch of the core is considered to be infinite.
  • Steel cords are prepared as shown in Table 3 and applied to a carcass ply of a radial tire for trucks and buses having a tire size of 11/70R22.5 14PR at an end count of 19.8 cords/5 cm.
  • the fretting depth and cord breakage under large bending force are measured in the same manner as in Example 1 by running such a tire on a drum under the same conditions as in Example 1.
  • steel cord of Comparative Example 5 having a layer twisting structure of 3+9+15+1 and a wrap steel filament of S-lay (control)
  • steel cord of Comparative Example 6 having a layer twisting structure of 3+9+15 and no wrap steel filament
  • steel cord of Example 3 having a layer twisting structure of 3+9+15+1 and a wrap steel filament of Z-lay according to the invention.
  • the measured results are shown in Table 3.
  • Steel cords are prepared as shown in Table 4 and applied to a carcass ply of a radial tire for trucks and buses having a tire size of 11/70R22.5 14PR at an end count of 31.8 cords/5 cm.
  • the fretting depth and cord breakage under large bending force are measured in the same manner as in Example 1 by running such a tire on a drum under the same conditions as in Example 1.
  • steel cord of Comparative Example 7 having a layer twisting structure of 3+8+1 and a wrap steel filament of Z-lay (control)
  • steel cord of Comparative Example 8 having a layer twisting structure of 3+8 and no wrap steel filament
  • steel cord of Example 4 having a layer twisting structure of 3+8+1 and a wrap steel filament of S-lay according to the invention.
  • the measured results are shown in Table 4.
  • the steel cord according to the invention has such a layer twisting structure that the wrap steel filament is spirally wound around the outermost sheath layer in the same direction as in the steel filaments of the outermost sheath layer.
  • the fretting between the steel filaments of the outermost sheath layer and the wrap steel filament is decreased and also the lowering of tensile load in the steel filaments of the cord becomes equal to improve the cord life, so that the tire durability can considerably be improved.

Landscapes

  • Ropes Or Cables (AREA)
  • Tires In General (AREA)

Claims (4)

  1. Câblé en acier pour le renforcement d'articles en caoutchouc, formé en torsadant de 1 à 4 filaments en acier comme partie centrale (1) et d'au moins une couche de gainage (2, 3) comprenant plusieurs filaments en acier arrangés autour de la partie centrale, dans lequel le pas de torsion d'au moins une couche de gainage est différent de celui d'une couche de gainage restante adjacente à la première ou de celui de la partie centrale, et dans lequel un filament d'enroulement en acier (4) est enroulé en spirale autour d'une couche de gainage située du côté le plus externe de câblé en acier, caractérisé en ce que ledit filament d'enroulement en acier (4) est enroulé dans la même direction de torsion que ladite couche de gainage.
  2. Câblé en acier selon la revendication 1, caractérisé en ce que ledit filament d'enroulement en acier (4) est enroulé autour de ladite couche de gainage la plus externe à un pas de torsion de 2-6 mm.
  3. Câblé en acier selon la revendication 1 ou 2, caractérisé en ce que ledit câblé possède une structure de torsion en couches choisie parmi les types 3+9+1, 3+8+1, 1+6+12+1 et 3+9+15+1.
  4. Bandage pneumatique radial comprenant une nappe de carcasse de structure radiale s'étendant en forme toroïdale entre une paire de portions de talons et contenant des câblés en acier, caractérisé en ce que ledit câblé en acier est tel que revendiqué dans l'une quelconque des revendications 1 à 3.
EP19930303148 1992-04-27 1993-04-22 Câbles d'acier pour le renforcement des articles en caoutchouc et des bandages pneumatiques radiaux Expired - Lifetime EP0568271B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP107742/92 1992-04-27
JP10774292 1992-04-27

Publications (2)

Publication Number Publication Date
EP0568271A1 EP0568271A1 (fr) 1993-11-03
EP0568271B1 true EP0568271B1 (fr) 1996-06-19

Family

ID=14466812

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19930303148 Expired - Lifetime EP0568271B1 (fr) 1992-04-27 1993-04-22 Câbles d'acier pour le renforcement des articles en caoutchouc et des bandages pneumatiques radiaux

Country Status (3)

Country Link
EP (1) EP0568271B1 (fr)
DE (1) DE69303222T2 (fr)
ES (1) ES2090867T3 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2795751A1 (fr) 1999-06-29 2001-01-05 Michelin Soc Tech Cable d'acier multicouches pour carcasse de pneumatique
FR2833277A1 (fr) * 2001-12-07 2003-06-13 Michelin Soc Tech Cable metallique utilisable pour renforcer une armature de carcasse d'un pneumatique et un tel pneumatique
FR2843361B1 (fr) * 2002-08-07 2005-04-08 Otico Cable de renforcement pour chenille souple sans fin
JP5692749B2 (ja) * 2011-02-24 2015-04-01 株式会社ブリヂストン ゴム物品補強用スチールコードおよびゴム−スチールコード複合体

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB720149A (en) * 1952-06-17 1954-12-15 Dunlop Rubber Co Improvements in or relating to pneumatic tyres
JP2659072B2 (ja) * 1988-12-16 1997-09-30 住友電気工業株式会社 ゴム補強用スチールコード
JPH0811872B2 (ja) * 1990-11-29 1996-02-07 株式会社ブリヂストン ゴム物品補強用スチールコード及び空気入りラジアルタイヤ

Also Published As

Publication number Publication date
DE69303222D1 (de) 1996-07-25
EP0568271A1 (fr) 1993-11-03
DE69303222T2 (de) 1996-12-05
ES2090867T3 (es) 1996-10-16

Similar Documents

Publication Publication Date Title
EP2065511B1 (fr) Cable metallique de renforcement de caoutchouc et pneumatique radial associe
EP0460705B1 (fr) Cordes en acier pour le renforcement de produits en caoutchouc
EP0719889B1 (fr) Câbles d'acier pour le renforcement d'articles en caoutchouc
US5396942A (en) Pneumatic radial tires with core-sheath steel belt cords
EP0752325A1 (fr) Pneu a carcasse radiale
EP0834613B1 (fr) Cable d'acier destine au renfort d'article en caoutchouc et pneumatique
EP0488735B1 (fr) Câbles d'acier destinés au renforcement de caoutchouc et aux bandages pneumatiques radiaux
EP1344864B1 (fr) Cable d'acier, procédé pour sa fabrication et pneumatique comportant un tel cable
EP0669421B1 (fr) Câbles d'acier pour le renforcement d'articles en caoutchouc et bandages pneumatiques radiaux comportant de tels câbles
EP0568271B1 (fr) Câbles d'acier pour le renforcement des articles en caoutchouc et des bandages pneumatiques radiaux
JP3187601B2 (ja) ゴム物品補強用スチールコードおよび空気入りラジアルタイヤ
EP1001074B1 (fr) Câbles d'acier pour le renforcement des articles en caoutchouc et pneumatiques
JPH1128906A (ja) 空気入りラジアルタイヤ
US5871603A (en) Pneumatic tires with organic or inorganic fiber cord bead core
JPH07117406A (ja) 重荷重用空気入りラジアルタイヤ
JPH10280288A (ja) ゴム補強用スチールコードおよびそれを使用した重荷重用ラジアルタイヤ
JP3529875B2 (ja) ゴム物品補強用スチールコードおよび空気入りラジアルタイヤ
JPH09209281A (ja) ゴム補強用スチールコード及びそれを使用したラジアルタイヤ
JPH10131065A (ja) ゴム物品補強用スチールコードおよびそれを使用した重荷重用ラジアルタイヤ
JPH05279975A (ja) 空気入りラジアルタイヤ
JPH08176977A (ja) ゴム補強用スチールコード及びそれを使用したラジアルタイヤ
JPS6241338A (ja) ゴム物品補強用スチ−ルコ−ド

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): BE DE ES FR GB IT

17P Request for examination filed

Effective date: 19931018

17Q First examination report despatched

Effective date: 19950116

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): BE DE ES FR GB IT

ITF It: translation for a ep patent filed
REF Corresponds to:

Ref document number: 69303222

Country of ref document: DE

Date of ref document: 19960725

ET Fr: translation filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2090867

Country of ref document: ES

Kind code of ref document: T3

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2090867

Country of ref document: ES

Kind code of ref document: T3

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

Ref country code: FR

Payment date: 19970409

Year of fee payment: 5

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

Ref country code: GB

Payment date: 19970414

Year of fee payment: 5

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: ES

Payment date: 19970428

Year of fee payment: 5

Ref country code: DE

Payment date: 19970428

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: BE

Payment date: 19970612

Year of fee payment: 5

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

Ref country code: GB

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

Effective date: 19980422

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 EXPIRATION OF PROTECTION

Effective date: 19980423

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: 19980430

Ref country code: BE

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

Effective date: 19980430

BERE Be: lapsed

Owner name: BRIDGESTONE CORP.

Effective date: 19980430

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

Effective date: 19980422

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: 19990202

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: 20000601

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

Ref country code: IT

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

Effective date: 20050422