EP3579990A1 - Electrohydraulic forming device - Google Patents

Electrohydraulic forming device

Info

Publication number
EP3579990A1
EP3579990A1 EP18703599.3A EP18703599A EP3579990A1 EP 3579990 A1 EP3579990 A1 EP 3579990A1 EP 18703599 A EP18703599 A EP 18703599A EP 3579990 A1 EP3579990 A1 EP 3579990A1
Authority
EP
European Patent Office
Prior art keywords
electrode
electrohydroforming
central electrode
peripheral electrode
peripheral
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.)
Granted
Application number
EP18703599.3A
Other languages
German (de)
French (fr)
Other versions
EP3579990B1 (en
Inventor
Gilles Avrillaud
Julien DEROY
Romain PECQUOIS
Pierre THOUET
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.)
ADM28 SARL
Original Assignee
ADM28 SARL
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 ADM28 SARL filed Critical ADM28 SARL
Publication of EP3579990A1 publication Critical patent/EP3579990A1/en
Application granted granted Critical
Publication of EP3579990B1 publication Critical patent/EP3579990B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/06—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure by shock waves
    • B21D26/12—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure by shock waves initiated by spark discharge

Definitions

  • the present invention relates to an electrohydroforming device.
  • Electrohydraulic forming also called electrohydroforming, makes it possible to deform a blank of material against a mold by applying a dynamic pressure. For this purpose, an electrical discharge is generated between at least two electrodes placed in a chamber filled with liquid, for example water. An electric arc is then formed between the two electrodes causing a high temperature gradient and the vaporization of the liquid. A pressure wave, also commonly known as a "shock wave", moves at high speed and presses the blank of material against the mold. Electrohydraulic forming is particularly advantageous in comparison with other forming processes since it allows a reduced elastic return and to obtain engraved type details and / or sharp angles and / or improved local elongations before rupture. the pieces to be formed.
  • Electrohydraulic forming or electrohydroforming has disadvantages.
  • One of the disadvantages of electrohydroforming is that the electrodes wear out quickly. As a result, the distance between the electrodes increases and the electric discharge is less strong. The efficiency of electrohydroforming is decreasing.
  • the electrodes are replaced regularly. The replacement of the electrodes generates additional maintenance costs and implies a decrease in the rate of production following a temporary immobilization of the apparatus.
  • US 4,068,514 discloses an electrohydroforming device comprising a central electrode extending in a longitudinal direction and a peripheral electrode formed by the wall of the forming chamber surrounding the central electrode. Since the wear of the peripheral electrode is distributed over a larger area, the distance between the electrodes varies less than with a device in which two electrodes, most often conical, are placed face to face and whose active parts are therefore very localized.
  • the electrodes can therefore be used longer without the efficiency of electrohydroforming, and in particular the pressure generated by the shock wave, is affected.
  • the replacement of an electrode involves the change of the entire electrohydroforming chamber which generates higher maintenance costs than for the other devices of the prior art and a temporary immobilization of the apparatus to replace the electrohydroforming chamber. longer electrode.
  • the present invention aims in particular to overcome the disadvantages of the aforementioned prior art.
  • the present invention provides a device for electrohydroforming a blank of material comprising:
  • At least one so-called central electrode extending in a so-called longitudinal direction and having a first end disposed inside the electrohydroforming chamber
  • peripheral electrode electrically isolated from each central electrode, having an end disposed at a distance and around the end of a central electrode, said end extending in a plane transverse to said central electrode,
  • a body provided with a bore for introducing each central electrode into the electrohydroforming chamber, the electrohydroforming chamber being partly formed by said body, and
  • each peripheral electrode is distinct from said body.
  • the use of a peripheral electrode distinct from the body partially forming the electrohydroforming chamber makes it possible to reduce the size of the peripheral electrode to be changed and the immobilization time of the device during the change of electrodes , thus reducing maintenance costs.
  • at least one peripheral electrode protrudes from the body, allowing better control over where the discharge occurs and increasing the efficiency of the electrohydroforming.
  • the at least one peripheral electrode is supported by an electrode holder.
  • an electrode holder reduces the size of the peripheral electrode to be changed and simplifies the replacement of the peripheral electrode.
  • the electrode holder can also act as a blank holder. This gives a compact electrohydroforming device and easy to assemble.
  • the device comprises a single peripheral electrode and at least one central electrode.
  • the electrohydroforming device may comprise several pairs of central and peripheral electrodes associated with one or more molds. It is thus possible to produce several parts in parallel or a large part by implementing several electric discharges in parallel.
  • the electrohydroforming chamber is formed by a body and the end of the peripheral electrode.
  • the electrohydroforming chamber is then closed by the blank of material to be deformed. This embodiment is advantageous because it is easy to machine and assemble.
  • a blank of material is held between the end of the peripheral electrode and the mold.
  • the end of the peripheral electrode may comprise a shoulder in which is housed the blank of material.
  • the peripheral electrode then serves as a blank holder and keeps the blank of material against the mold.
  • the device comprises a blank holder disposed between the end of the peripheral electrode and the mold.
  • the device further comprises a mold support that makes it easier to change the mold depending on the part to be formed.
  • the central electrode is surrounded over a portion of its length by an electrical insulator.
  • the body is in electrical contact with the central electrode and further comprises an electrical insulator for isolating the peripheral electrode from the central electrode.
  • the body When the central electrode is surrounded over a portion of its length by an electrical insulator, the body is easier to machine and assemble than when the body comprises the electrical insulator for isolating the peripheral electrode of the central electrode.
  • the body further comprises a cavity forming in part the electrohydroforming chamber and the electrical insulator forms at least partly a side wall of said cavity.
  • the electrical insulator constitutes the side wall of the cavity.
  • the insulator on the side wall is less stressed than when it surrounds the central electrode and form in part of the bottom wall of the cavity.
  • the end of the peripheral electrode and the mold are in electrical contact and subjected to a first electrical potential, the central electrode being subjected to a second electrical potential.
  • the central electrode and the mold When the peripheral electrode and the mold are in electrical contact, possibly via a mold support and / or a blank holder, the central electrode being otherwise isolated, it is easy to generate the discharge by connecting the central electrode or the body, if it is in electrical contact with the central electrode, to one of the terminals of a pulse voltage generator and by connecting one of the elements to the electrical contact of the peripheral electrode to the other terminal of the pulse voltage generator.
  • the design of the electrohydroforming device is therefore easier since the electrical connections with the terminals of the high-voltage pulse generator are not necessarily established at the level of the central and peripheral electrodes.
  • FIG. 1A shows a sectional view of an electrohydroforming device according to a first embodiment of the invention
  • FIG. 1B represents a sectional view of an electrohydroforming device according to an embodiment variant
  • FIG. 2 represents a sectional view of an electrohydroforming device according to a second embodiment of the invention
  • FIGS. 3A, 3B, 3C and 3D show a sectional view of the active parts of different central and peripheral electrodes according to FIG. different embodiments.
  • FIG. 1A represents a first embodiment of an electrohydroforming device according to the invention.
  • the electrohydroforming device 100 comprises an electrohydroforming chamber 1 10, a central electrode 120 and a peripheral electrode 130.
  • the central electrode 120 extends in a longitudinal direction XX 'and has a first end 122 disposed inside. of the electrohydroforming chamber 1 10.
  • the peripheral electrode 130 has an end 132 disposed at a distance and around the end 122 of the central electrode 120.
  • the end 132 of the peripheral electrode 130 extends in a plane transverse to said central electrode 120, that is to say in the plane perpendicular to the axis XX '.
  • the electrohydroforming device 100 also comprises a body 140 and a mold 150.
  • the body 140 has an internal cavity 142 and is traversed by the central electrode 120.
  • the internal cavity 142 of the body forms, with the end 132 of the peripheral electrode 130, the electrohydroforming chamber 1 10.
  • the electrohydroforming chamber 1 10 is intended to be filled with a liquid, for example water, and is closed by a blank of material 160 to be deformed.
  • the blank of material 160 is pressed against the mold 150 and is deformed against the mold 150 under the action of a shock wave propagating in the electrohydroforming chamber 1 10.
  • the shock wave is generated following the applying a high voltage electrical pulse between the electrodes 120 and 130 and generating an electric discharge between the electrodes.
  • the electric discharge causes the formation of an electric arc, an increase in temperature and the vaporization of the liquid causing the creation of the shock wave.
  • a portion of the end 132 of the peripheral electrode 130 surrounds the lower end 122 of the central electrode 120.
  • An electric arc is preferably created between two zones 124 and 134, called active portions. , the central electrode 120 and the peripheral electrode 130 respectively.
  • an electric arc is preferably created between two different points of the outer surface 125 of the active portion 124 of the central electrode 120 and the inner surface 135 of the active portion 134 of the peripheral electrode 130 corresponding to the shorter path between the center electrode 120 and the peripheral electrode 130, respectively.
  • each electrode is used locally at different points distributed on the outer surface 125 of the active portion 124 of the central electrode 120 and on the inner surface 135 of the active portion 134 of the peripheral electrode 130.
  • the peripheral electrode being distributed over a larger area, the distance between the electrodes varies less than with a device of the prior art in which two electrodes, usually conical, are placed face to face and whose active parts are therefore very localized.
  • the electrodes can therefore be used longer without the effectiveness of the electrohydroforming, and in particular the pressure generated by the shock wave, is affected.
  • section of the central electrode is not necessarily constant along its longitudinal axis XX 'as illustrated by example with reference to Figure 2.
  • section of the electrode is not necessarily axisymmetric.
  • the material blank 160 is held against the mold 150 by the peripheral electrode 130 (FIG. 1A).
  • the peripheral electrode 130 also comprises, on its lower face, a shoulder in which the blank of material 160 can be housed.
  • the peripheral electrode 130 then serves as a blank holder and makes it possible to hold the blank of material 160 against the mold 150.
  • the electrohydroforming device 100 ' furthermore comprises an electrode holder 136 supporting the peripheral electrode 130.
  • the electrode holder 136 is disposed between the mold 150 and the body 140. It comprises on its underside a shoulder in which can be accommodated the blank of material 160 and on its upper face a housing adapted to accommodate the peripheral electrode 132.
  • the electrode holder 136 therefore also acts as a blank holder to hold the blank of material 160 against the mold 150.
  • an additional piece 280 may be used to act as a blank holder and hold the blank of material to deform against the mold as illustrated with reference to Figure 2, for example.
  • the electrode holder 136 has no shoulder on its underside.
  • the body 140, the peripheral electrode 130 and the mold 150 are in electrical contact with each other when they consist of a conductive material such as steel, or any other alloy metallic.
  • an electrical insulator 1 15 surrounds the central electrode 120 over at least part of its length, in particular on the part of the central electrode 120 housed in the body 140.
  • the central electrode 120 is therefore electrically isolated from the peripheral electrode 130, even if the body 140 is in electrical contact with the peripheral electrode 130.
  • the central electrode 120 can therefore be subjected to a first electrical potential by connecting it to one of the terminals a high voltage pulse generator 170 and connecting the body 140, the peripheral electrode 130 or the mold 150 to the other terminal of the pulse generator high voltage 170.
  • This form of implementation of the invention is particularly advantageous because easy to machine and assemble.
  • the mold 150 may consist of a single piece or be attached to an additional piece called mold support, thus making it easier to change the mold depending on the workpiece.
  • the central electrode can be fixed in the electrohydroforming device by various means. It can, for example, be maintained using an additional piece (not shown) electrically isolated from the body.
  • the assembly formed by the mold and the peripheral electrode is movable relative to the body comprising the central electrode and the body is preferably fixed.
  • the peripheral electrode is then fixed on the mold.
  • the mold is mounted on the plate of a press and the peripheral electrode is fixed directly on the body.
  • the blank of material is held between the peripheral electrode and the mold when the mold is held against the peripheral electrode with the aid of the press.
  • peripheral electrode is easily accessible and can be easily changed.
  • FIG. 2 represents a second embodiment of an electrohydroforming device according to the invention.
  • the electrohydroforming device 200 is similar to that shown with reference to the FIG. 1A in that it also comprises an electrohydroforming chamber 210, a central electrode 220, a peripheral electrode 230, a body 240 and a mold 250.
  • the electrohydroforming device 200 further comprises an additional piece 280 serving as a blank holder.
  • the device further comprises an electrode holder 232 on which is fixed the peripheral electrode 230.
  • the body 240 further comprises an electrical insulator 215 positioned, either between the body and the central electrode as illustrated with reference to FIGS. 1A and 1B, but for example on the lower part of the body 240.
  • the electrical insulator 215 forms the side wall 243 of the cavity 240 forming part of the electrohydroforming chamber 210. In other alternative embodiments, the electrical insulator 215 may form only part of the side wall.
  • the central electrode 220 and the upper part 241 of the body 240 are then in electrical contact and the upper part 241 of the body 240, for example, can be connected to a first terminal of the high voltage pulse generator 270.
  • the peripheral electrode 230, the electrode holder 232, the blank holder 280 and the mold 250 are in electrical contact and the peripheral electrode 230 is connected to a second terminal of the high voltage pulse generator 270 via the electrode holder 232, the clamp blank 280 or mold 250 thus causing an electric discharge between the central electrode 220 and the peripheral electrode 230.
  • the shock wave thus generated propagates in a plane perpendicular to this discharge.
  • a portion of the shock wave propagates towards the bottom wall 244 and impacts the wall, which can damage it.
  • the insulation is located on the side wall, it is less stressed, which reduces the risk of damage.
  • the body 240 comprises a cavity 242 and that the side wall 243 and the bottom wall 244 can have different shapes adapted to a better confinement of the pressure waves towards the blank of material to be deformed.
  • the bottom wall 244 may be inclined to better reflect the shock waves to the blank of material to be deformed.
  • the active part 224 of the central electrode 220 and the active portion 234 of the peripheral electrode 230 are not necessarily of constant section and / or axisymmetric as illustrated with reference to FIG.
  • the electrohydroforming devices comprise only a central electrode and a peripheral electrode.
  • the electrohydroforming device may comprise several pairs of central and peripheral electrodes associated with one or more molds. It is thus possible to produce several parts in parallel or a large part by implementing several electric discharges in parallel.
  • FIGS. 3A-3D Different electrode shapes and different central electrode arrangements are illustrated with reference to FIGS. 3A-3D.
  • FIGS. 3A to 3D more particularly illustrate the active portions of central and peripheral electrodes seen in section along a plane ( ⁇ ', ⁇ ') perpendicular to the longitudinal axis XX 'of a central electrode.
  • the active part 301 of the central electrode is of circular shape and the active part 302 of the peripheral electrode has the shape of a circular ring.
  • the active parts 303, 305, 307 of several central electrodes are of rectangular section, preferably with rounded corners, and aligned in a common direction ZZ 'in the center of a ring of rectangular shape forming the active part 308 of the corresponding peripheral electrode.
  • the active parts 309, 31 1 of a plurality of central electrodes are of elliptical section and aligned in a common direction ZZ 'in the center of an elliptical ring forming the active part 312 of the corresponding peripheral electrode.
  • the active portions 313, 314, 315, 316 of four central electrodes are of square rectangular section, preferably with rounded corners, and are arranged inside a square-shaped ring forming the active part 317. of the corresponding peripheral electrode.
  • peripheral electrodes described here are formed in one piece.
  • the peripheral electrodes comprise different separate sections intended to be placed opposite each central electrode to generate discharges. These different sections therefore comprise the active parts of the peripheral electrode. This reduces the cost of replacement of the peripheral electrodes by replacing only certain sections. Note that other geometrical shapes may also be used provided that the distance between the outer surface of the active portion of the central electrode considered and the inner surface of the active portion of the surrounding peripheral electrode is substantially equidistant on the least a portion of the surfaces of the active parts considered in the plane.
  • the section of the active parts of the electrodes may be constant or vary in their longitudinal direction represented by the axis XX 'in FIGS. 1A, 1B and 2.
  • an electrohydroforming device allows the electrohydraulic forming of blanks of material with a peripheral electrode partially surrounding a central electrode, the peripheral electrode being distinct from the body forming in part the chamber of emperhydroformage.
  • the electric discharge is distributed over the periphery of the active parts of the electrodes.
  • the peripheral electrode which has a larger contact area, wears more slowly. Thus, the distance between the electrodes varies little, which keeps the efficiency of electrohydroforming by keeping a pressure generated by the substantially constant electric discharge.
  • the peripheral electrode may advantageously be easily changed when the electrohydroforming device is open to place the blank of material, the peripheral electrode being distinct from the body and the blank of material being preferentially placed between the peripheral electrode and the mold.
  • the central electrode may be displaced along its longitudinal axis in order to present to the peripheral electrode a less degraded active part.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)

Abstract

An electrohydraulic forming device (100) for forming a blank (160) of material, comprising: - an electrohydraulic forming chamber (110), - at least one central electrode (120) extending in a so-called longitudinal direction (XX') and comprising a first end (122) arranged inside the electrohydraulic forming chamber (110), - a body (140) provided with a bore for introducing each central electrode (120) into the electrohydraulic forming chamber, the electrohydraulic forming chamber being partially formed by said body (140), - a mould (150), and - at least one peripheral electrode (130) electrically insulated from each central electrode (120), having an end (132) arranged at a distance from and around the end (122) of a central electrode (120), said end (132) extending in a transverse plane relative to said central electrode (120).

Description

DISPOSITIF D'ELECTROHYDROFORMAGE  ELECTROHYDROFORMING DEVICE
Arrière-plan de l'invention Background of the invention
La présente invention concerne un dispositif d'électrohydroformage.  The present invention relates to an electrohydroforming device.
Objet et résumé de l'invention Object and summary of the invention
Le formage électrohydraulique, également appelé électrohydroformage, permet de déformer un flan de matière contre un moule par application d'une pression dynamique. A cet effet, on génère une décharge électrique entre au moins deux électrodes placées dans une chambre remplie de liquide, par exemple de l'eau. Un arc électrique est alors formé entre les deux électrodes provoquant un gradient de température élevé et la vaporisation du liquide. Une onde de pression, aussi communément appelée « onde de choc », se déplace à grande vitesse et vient plaquer le flan de matière contre le moule. Le formage électrohydraulique est particulièrement avantageux en comparaison avec les autres procédés de formage puisqu'il permet d'avoir un retour élastique réduit et d'obtenir des détails de type gravure et/ou des angles vifs et/ou des allongements locaux avant rupture améliorés sur les pièces à former.  Electrohydraulic forming, also called electrohydroforming, makes it possible to deform a blank of material against a mold by applying a dynamic pressure. For this purpose, an electrical discharge is generated between at least two electrodes placed in a chamber filled with liquid, for example water. An electric arc is then formed between the two electrodes causing a high temperature gradient and the vaporization of the liquid. A pressure wave, also commonly known as a "shock wave", moves at high speed and presses the blank of material against the mold. Electrohydraulic forming is particularly advantageous in comparison with other forming processes since it allows a reduced elastic return and to obtain engraved type details and / or sharp angles and / or improved local elongations before rupture. the pieces to be formed.
Le formage électrohydraulique ou électrohydroformage présente cependant des inconvénients. L'un des inconvénients de l'électrohydroformage est que les électrodes s'usent rapidement. De ce fait, la distance entre les électrodes augmente et la décharge électrique est moins forte. L'efficacité de l'électrohydroformage diminue. Afin de pallier à cet inconvénient, les électrodes sont remplacées régulièrement. Le remplacement des électrodes engendre des coûts supplémentaires de maintenance et implique une baisse de la cadence de production suite à une immobilisation temporaire de l'appareil.  Electrohydraulic forming or electrohydroforming, however, has disadvantages. One of the disadvantages of electrohydroforming is that the electrodes wear out quickly. As a result, the distance between the electrodes increases and the electric discharge is less strong. The efficiency of electrohydroforming is decreasing. In order to overcome this disadvantage, the electrodes are replaced regularly. The replacement of the electrodes generates additional maintenance costs and implies a decrease in the rate of production following a temporary immobilization of the apparatus.
Le document US4 068 514 décrit un dispositif d'électrohydroformage comprenant une électrode centrale s'étendant selon une direction longitudinale et une électrode périphérique formée par la paroi de la chambre de formage entourant l'électrode centrale. L'usure de l'électrode périphérique étant répartie sur une plus grande surface, la distance entre les électrodes varie moins qu'avec un dispositif dans lequel deux électrodes, le plus souvent coniques, sont placées face à face et dont les parties actives sont de ce fait très localisées. US 4,068,514 discloses an electrohydroforming device comprising a central electrode extending in a longitudinal direction and a peripheral electrode formed by the wall of the forming chamber surrounding the central electrode. Since the wear of the peripheral electrode is distributed over a larger area, the distance between the electrodes varies less than with a device in which two electrodes, most often conical, are placed face to face and whose active parts are therefore very localized.
Les électrodes peuvent donc être utilisées plus longtemps sans que l'efficacité de rélectrohydroformage, et notamment la pression générée par l'onde de choc, soit affectée. Cependant, le remplacement d'une électrode implique le changement de la totalité de la chambre d'électrohydroformage ce qui engendre des coûts de maintenance plus élevés que pour les autres dispositifs de l'art antérieur et une immobilisation temporaire de l'appareil pour remplacer l'électrode plus longue.  The electrodes can therefore be used longer without the efficiency of electrohydroforming, and in particular the pressure generated by the shock wave, is affected. However, the replacement of an electrode involves the change of the entire electrohydroforming chamber which generates higher maintenance costs than for the other devices of the prior art and a temporary immobilization of the apparatus to replace the electrohydroforming chamber. longer electrode.
La présente invention vise notamment à pallier aux inconvénients de l'art antérieur précités. The present invention aims in particular to overcome the disadvantages of the aforementioned prior art.
À cet effet, la présente invention propose un dispositif d'électrohydroformage d'un flan de matière comprenant :  For this purpose, the present invention provides a device for electrohydroforming a blank of material comprising:
- une chambre d'électrohydroformage,  an electrohydroforming chamber,
- au moins une électrode dite électrode centrale s'étendant selon une direction dite longitudinale et comportant une première extrémité disposée à l'intérieur de la chambre d'électrohydroformage, et  at least one so-called central electrode extending in a so-called longitudinal direction and having a first end disposed inside the electrohydroforming chamber, and
- au moins une électrode dite électrode périphérique électriquement isolée de chaque électrode centrale, présentant une extrémité disposée à distance et autour de l'extrémité d'une électrode centrale, ladite extrémité s'étendant dans un plan transversal par rapport à ladite électrode centrale,  at least one so-called peripheral electrode electrically isolated from each central electrode, having an end disposed at a distance and around the end of a central electrode, said end extending in a plane transverse to said central electrode,
- un corps muni d'un alésage pour l'introduction de chaque électrode centrale dans la chambre d'électrohydroformage, la chambre d'électrohydroformage étant en partie formée par ledit corps, et  a body provided with a bore for introducing each central electrode into the electrohydroforming chamber, the electrohydroforming chamber being partly formed by said body, and
- un moule.  - a mold.
En outre, chaque électrode périphérique est distincte dudit corps.  In addition, each peripheral electrode is distinct from said body.
Selon l'invention, l'utilisation d'une électrode périphérique distincte du corps formant en partie la chambre d'électrohydroformage permet de réduire la taille de l'électrode périphérique à changer et le temps d'immobilisation du dispositif lors du changement d'électrodes, réduisant ainsi les coûts de maintenance. Dans une forme de réalisation, Tau moins une électrode périphérique est en saillie par rapport au corps, ce qui permet de mieux contrôler l'endroit où se produit la décharge et d'augmenter l'efficacité de l'électrohydroformage. According to the invention, the use of a peripheral electrode distinct from the body partially forming the electrohydroforming chamber makes it possible to reduce the size of the peripheral electrode to be changed and the immobilization time of the device during the change of electrodes , thus reducing maintenance costs. In one embodiment, at least one peripheral electrode protrudes from the body, allowing better control over where the discharge occurs and increasing the efficiency of the electrohydroforming.
Dans une forme de réalisation, l'au moins une électrode périphérique est supportée par un porte-électrode.  In one embodiment, the at least one peripheral electrode is supported by an electrode holder.
L'utilisation d'un porte-électrode permet de réduire la taille de l'électrode périphérique devant être changée et de simplifier le remplacement de l'électrode périphérique. De manière avantageuse, le porte-électrode peut aussi faire office de serre-flan. On obtient ainsi un dispositif d'électrohydroformage compact et facile à assembler.  The use of an electrode holder reduces the size of the peripheral electrode to be changed and simplifies the replacement of the peripheral electrode. Advantageously, the electrode holder can also act as a blank holder. This gives a compact electrohydroforming device and easy to assemble.
Dans une forme de réalisation, le dispositif comporte une unique électrode périphérique et au moins une électrode centrale.  In one embodiment, the device comprises a single peripheral electrode and at least one central electrode.
Il peut être avantageux d'utiliser plusieurs électrodes centrales associées à une unique électrode périphérique, notamment dans le cas de pièces à former de grandes dimensions. En réalisant plusieurs décharges électriques simultanées ou différées à différents endroits, il est possible de réaliser un formage électrohydraulique plus homogène ou plus progressif ou plus profond qu'avec un dispositif d'électrohydroformage de l'art antérieur. Dans d'autres formes de réalisation, le dispositif d'électrohydroformage peut comporter plusieurs paires d'électrodes centrales et périphériques associées à un ou plusieurs moules. Il est ainsi possible de réaliser plusieurs pièces en parallèle ou une grande pièce en mettant en œuvre parallèlement plusieurs décharges électriques.  It may be advantageous to use a plurality of central electrodes associated with a single peripheral electrode, particularly in the case of large-sized workpieces. By performing several simultaneous or delayed electrical discharges in different places, it is possible to achieve an electrohydraulic forming more homogeneous or more progressive or deeper than with an electrohydroforming device of the prior art. In other embodiments, the electrohydroforming device may comprise several pairs of central and peripheral electrodes associated with one or more molds. It is thus possible to produce several parts in parallel or a large part by implementing several electric discharges in parallel.
Dans une forme de réalisation, la chambre d'électrohydroformage est formée par un corps et par l'extrémité de l'électrode périphérique. La chambre d'électrohydroformage est alors fermée par le flan de matière à déformer. Cette forme de réalisation est avantageuse car facile à usiner et à assembler.  In one embodiment, the electrohydroforming chamber is formed by a body and the end of the peripheral electrode. The electrohydroforming chamber is then closed by the blank of material to be deformed. This embodiment is advantageous because it is easy to machine and assemble.
Dans une forme de réalisation, un flan de matière est maintenu entre l'extrémité de l'électrode périphérique et le moule. On obtient ainsi un dispositif d'électrohydroformage compact et facile à assembler. De manière avantageuse, l'extrémité de l'électrode périphérique peut comprendre un épaulement dans lequel vient se loger le flan de matière. L'électrode périphérique fait alors office de serre-flan et permet de maintenir le flan de matière contre le moule. In one embodiment, a blank of material is held between the end of the peripheral electrode and the mold. This gives a compact electrohydroforming device and easy to assemble. Advantageously, the end of the peripheral electrode may comprise a shoulder in which is housed the blank of material. The peripheral electrode then serves as a blank holder and keeps the blank of material against the mold.
Dans une variante de réalisation, le dispositif comprend un serre-flan disposé entre l'extrémité de l'électrode périphérique et le moule.  In an alternative embodiment, the device comprises a blank holder disposed between the end of the peripheral electrode and the mold.
Dans une forme de réalisation, le dispositif comporte en outre un support de moule qui permet de changer plus facilement le moule en fonction de la pièce à former.  In one embodiment, the device further comprises a mold support that makes it easier to change the mold depending on the part to be formed.
Dans une forme de réalisation, l'électrode centrale est entourée sur une partie de sa longueur par un isolant électrique.  In one embodiment, the central electrode is surrounded over a portion of its length by an electrical insulator.
Dans une autre variante de réalisation, le corps est en contact électrique avec l'électrode centrale et comprend en outre un isolant électrique destiné à isoler l'électrode périphérique de l'électrode centrale.  In another alternative embodiment, the body is in electrical contact with the central electrode and further comprises an electrical insulator for isolating the peripheral electrode from the central electrode.
Lorsque l'électrode centrale est entourée sur une partie de sa longueur par un isolant électrique, le corps est plus facile à usiner et à assembler que lorsque le corps comprend l'isolant électrique destiné à isoler l'électrode périphérique de l'électrode centrale.  When the central electrode is surrounded over a portion of its length by an electrical insulator, the body is easier to machine and assemble than when the body comprises the electrical insulator for isolating the peripheral electrode of the central electrode.
Avantageusement, le corps comporte en outre une cavité formant en partie la chambre d'électrohydroformage et l'isolant électrique forme au moins en partie une paroi latérale de ladite cavité. De manière particulièrement avantageuse, l'isolant électrique constitue la paroi latérale de la cavité.  Advantageously, the body further comprises a cavity forming in part the electrohydroforming chamber and the electrical insulator forms at least partly a side wall of said cavity. Particularly advantageously, the electrical insulator constitutes the side wall of the cavity.
Une partie de l'onde de choc se propageant en direction de la paroi de fond de la cavité où débouche l'électrode centrale, l'isolant situé sur la paroi latérale est moins sollicité que lorsqu'il entoure l'électrode centrale et forme en partie la paroi de fond de la cavité.  Part of the shock wave propagating towards the bottom wall of the cavity where the central electrode opens, the insulator on the side wall is less stressed than when it surrounds the central electrode and form in part of the bottom wall of the cavity.
Dans une forme de réalisation, l'extrémité de l'électrode périphérique et le moule sont en contact électrique et soumis à un premier potentiel électrique, l'électrode centrale étant soumise à un second potentiel électrique.  In one embodiment, the end of the peripheral electrode and the mold are in electrical contact and subjected to a first electrical potential, the central electrode being subjected to a second electrical potential.
Lorsque l'électrode périphérique et le moule sont en contact électrique, éventuellement par l'intermédiaire d'un support de moule et/ou d'un serre-flan, l'électrode centrale étant par ailleurs isolée, il est aisé de générer la décharge électrique en reliant l'électrode centrale ou le corps, s'il est en contact électrique avec l'électrode centrale, à l'une des bornes d'un générateur de tension impulsionnel et en reliant l'un des éléments au contact électrique de l'électrode périphérique à l'autre borne du générateur de tension impulsionnel. La conception du dispositif d'électrohydroformage est donc plus aisée puisque les connexions électriques avec les bornes du générateur impulsionnel haute- tension ne sont pas nécessairement établies au niveau des électrodes centrales et périphériques. When the peripheral electrode and the mold are in electrical contact, possibly via a mold support and / or a blank holder, the central electrode being otherwise isolated, it is easy to generate the discharge by connecting the central electrode or the body, if it is in electrical contact with the central electrode, to one of the terminals of a pulse voltage generator and by connecting one of the elements to the electrical contact of the peripheral electrode to the other terminal of the pulse voltage generator. The design of the electrohydroforming device is therefore easier since the electrical connections with the terminals of the high-voltage pulse generator are not necessarily established at the level of the central and peripheral electrodes.
Brève description des dessins Brief description of the drawings
Des détails et avantages de la présente invention apparaîtront mieux de la description qui suit, faite en référence aux dessins annexés sur lesquels : la figure 1A représente une vue en coupe d'un dispositif d'électrohydroformage selon une première forme de réalisation de l'invention, la figure 1 B représente une vue en coupe d'un dispositif d'électrohydroformage selon une variante de réalisation,  Details and advantages of the present invention will become more apparent from the following description, with reference to the accompanying drawings, in which: FIG. 1A shows a sectional view of an electrohydroforming device according to a first embodiment of the invention FIG. 1B represents a sectional view of an electrohydroforming device according to an embodiment variant,
la figure 2 représente une vue en coupe d'un dispositif d'électrohydroformage selon une seconde forme de réalisation de l'invention, les figures 3A, 3B, 3C et 3D représentent une vue en coupe des parties actives de différentes électrode centrales et périphériques selon différentes variantes de réalisation.  FIG. 2 represents a sectional view of an electrohydroforming device according to a second embodiment of the invention; FIGS. 3A, 3B, 3C and 3D show a sectional view of the active parts of different central and peripheral electrodes according to FIG. different embodiments.
Description détaillée de plusieurs modes de réalisation de l'invention Detailed description of several embodiments of the invention
La figure 1A représente une première forme de réalisation d'un dispositif d'électrohydroformage selon l'invention. Le dispositif d'électrohydroformage 100 comprend une chambre d'électrohydroformage 1 10, une électrode centrale 120 et une électrode périphérique 130. L'électrode centrale 120 s'étend selon une direction longitudinale XX' et comporte une première extrémité 122 disposée à l'intérieur de la chambre d'électrohydroformage 1 10. L'électrode périphérique 130 présente une extrémité 132 disposée à distance et autour de l'extrémité 122 de l'électrode centrale 120. L'extrémité 132 de l'électrode périphérique 130 s'étend dans un plan transversal par rapport à ladite électrode centrale 120, c'est-à-dire dans le plan perpendiculaire à l'axe XX'.  FIG. 1A represents a first embodiment of an electrohydroforming device according to the invention. The electrohydroforming device 100 comprises an electrohydroforming chamber 1 10, a central electrode 120 and a peripheral electrode 130. The central electrode 120 extends in a longitudinal direction XX 'and has a first end 122 disposed inside. of the electrohydroforming chamber 1 10. The peripheral electrode 130 has an end 132 disposed at a distance and around the end 122 of the central electrode 120. The end 132 of the peripheral electrode 130 extends in a plane transverse to said central electrode 120, that is to say in the plane perpendicular to the axis XX '.
Le dispositif d'électrohydroformage 100 comprend également un corps 140 et un moule 150. Le corps 140 comporte une cavité interne 142 et est traversé par l'électrode centrale 120. La cavité interne 142 du corps forme, avec l'extrémité 132 de l'électrode périphérique 130, la chambre d'électrohydroformage 1 10. The electrohydroforming device 100 also comprises a body 140 and a mold 150. The body 140 has an internal cavity 142 and is traversed by the central electrode 120. The internal cavity 142 of the body forms, with the end 132 of the peripheral electrode 130, the electrohydroforming chamber 1 10.
La chambre d'électrohydroformage 1 10 est destinée à être remplie d'un liquide, par exemple de l'eau, et est fermée par un flan de matière 160 à déformer. Le flan de matière 160 est plaqué contre le moule 150 et se déforme contre le moule 150 sous l'action d'une onde de choc se propageant dans la chambre d'électrohydroformage 1 10. L'onde de choc est générée suite à l'application d'une impulsion électrique à haute tension entre les électrodes 120 et 130 et la génération d'une décharge électrique entre les électrodes. La décharge électrique entraine la formation d'un arc électrique, une augmentation de température et la vaporisation du liquide provoquant la création de l'onde de choc.  The electrohydroforming chamber 1 10 is intended to be filled with a liquid, for example water, and is closed by a blank of material 160 to be deformed. The blank of material 160 is pressed against the mold 150 and is deformed against the mold 150 under the action of a shock wave propagating in the electrohydroforming chamber 1 10. The shock wave is generated following the applying a high voltage electrical pulse between the electrodes 120 and 130 and generating an electric discharge between the electrodes. The electric discharge causes the formation of an electric arc, an increase in temperature and the vaporization of the liquid causing the creation of the shock wave.
Dans la forme de réalisation décrite ici, une partie de l'extrémité 132 de l'électrode périphérique 130 entoure l'extrémité 122 inférieure de l'électrode centrale 120. Un arc électrique se crée préférentiellement entre deux zones 124 et 134, appelées parties actives, de l'électrode centrale 120 et de l'électrode périphérique 130 respectivement. Après chaque décharge électrique, un arc électrique se crée préférentiellement entre deux points différents de la surface externe 125 de la partie active 124 de l'électrode centrale 120 et de la surface interne 135 de la partie active 134 de l'électrode périphérique 130 correspondant au plus court chemin entre l'électrode centrale 120 et l'électrode périphérique 130, respectivement. Ainsi, chaque électrode s'use localement en différents points répartis sur la surface externe 125 de la partie active 124 de l'électrode centrale 120 et sur la surface interne 135 de la partie active 134 de l'électrode périphérique 130. L'usure de l'électrode périphérique étant répartie sur une plus grande surface, la distance entre les électrodes varie moins qu'avec un dispositif de l'art antérieur dans lequel deux électrodes, le plus souvent coniques, sont placées face à face et dont les parties actives sont de ce fait très localisées. Les électrodes peuvent donc être utilisées plus longtemps sans que l'efficacité de l'électrohydroformage, et notamment la pression générée par l'onde de choc, soit affectée.  In the embodiment described here, a portion of the end 132 of the peripheral electrode 130 surrounds the lower end 122 of the central electrode 120. An electric arc is preferably created between two zones 124 and 134, called active portions. , the central electrode 120 and the peripheral electrode 130 respectively. After each electric discharge, an electric arc is preferably created between two different points of the outer surface 125 of the active portion 124 of the central electrode 120 and the inner surface 135 of the active portion 134 of the peripheral electrode 130 corresponding to the shorter path between the center electrode 120 and the peripheral electrode 130, respectively. Thus, each electrode is used locally at different points distributed on the outer surface 125 of the active portion 124 of the central electrode 120 and on the inner surface 135 of the active portion 134 of the peripheral electrode 130. the peripheral electrode being distributed over a larger area, the distance between the electrodes varies less than with a device of the prior art in which two electrodes, usually conical, are placed face to face and whose active parts are therefore very localized. The electrodes can therefore be used longer without the effectiveness of the electrohydroforming, and in particular the pressure generated by the shock wave, is affected.
On notera par ailleurs que la section de l'électrode centrale n'est pas forcément constante le long de son axe longitudinal XX' comme illustré par exemple en référence à la figure 2. En outre, la section de l'électrode n'est pas forcément axisymétrique. Note also that the section of the central electrode is not necessarily constant along its longitudinal axis XX 'as illustrated by example with reference to Figure 2. In addition, the section of the electrode is not necessarily axisymmetric.
Le flan de matière 160 est maintenu contre le moule 150 par l'électrode périphérique 130 (figure 1A). A cet effet, l'électrode périphérique 130 comprend également, sur sa face inférieure, un épaulement dans lequel peut être logé le flan de matière 160. L'électrode périphérique 130 fait alors office de serre-flan et permet de maintenir le flan de matière 160 contre le moule 150.  The material blank 160 is held against the mold 150 by the peripheral electrode 130 (FIG. 1A). For this purpose, the peripheral electrode 130 also comprises, on its lower face, a shoulder in which the blank of material 160 can be housed. The peripheral electrode 130 then serves as a blank holder and makes it possible to hold the blank of material 160 against the mold 150.
Dans une variante de réalisation représentée sur la figure 1 B, le dispositif d'électrohydroformage 100', de structure similaire à celle du dispositif représenté en référence à la figure 1A, comporte en outre un porte-électrode 136 supportant l'électrode périphérique 130. Le porte-électrode 136 est disposé entre le moule 150 et le corps 140. Il comprend sur sa face inférieure un épaulement dans lequel peut être logé le flan de matière 160 et sur sa face supérieure un logement adapté pour accueillir l'électrode périphérique 132. Le porte-électrode 136 fait donc également office de serre-flan pour maintenir le flan de matière 160 contre le moule 150.  In an alternative embodiment shown in FIG. 1B, the electrohydroforming device 100 ', similar in structure to that of the device shown with reference to FIG. 1A, furthermore comprises an electrode holder 136 supporting the peripheral electrode 130. The electrode holder 136 is disposed between the mold 150 and the body 140. It comprises on its underside a shoulder in which can be accommodated the blank of material 160 and on its upper face a housing adapted to accommodate the peripheral electrode 132. The electrode holder 136 therefore also acts as a blank holder to hold the blank of material 160 against the mold 150.
Dans d'autres variantes de réalisation, une pièce supplémentaire 280 peut être utilisée pour faire office de serre-flan et maintenir le flan de matière à déformer contre le moule tel qu'illustré en référence à la figure 2, par exemple. Dans ce cas, le porte-électrode 136 ne comporte pas d'épaulement sur sa face inférieure.  In other embodiments, an additional piece 280 may be used to act as a blank holder and hold the blank of material to deform against the mold as illustrated with reference to Figure 2, for example. In this case, the electrode holder 136 has no shoulder on its underside.
On remarquera par ailleurs que le corps 140, l'électrode périphérique 130 et le moule 150 sont en contact électrique l'un avec l'autre lorsque ceux-ci sont constitués d'un matériau conducteur tel que l'acier, ou tout autre alliage métallique. Dans la forme de réalisation décrite ici, un isolant électrique 1 15 entoure l'électrode centrale 120 sur une partie de sa longueur au moins, notamment sur la partie de l'électrode centrale 120 logée dans le corps 140. L'électrode centrale 120 est donc isolée électriquement de l'électrode périphérique 130, même si le corps 140 est en contact électrique avec l'électrode périphérique 130. L'électrode centrale 120 peut donc être soumise à un premier potentiel électrique en la reliant à l'une des bornes d'un générateur impulsionnel haute tension 170 et en reliant le corps 140, l'électrode périphérique 130 ou le moule 150 à l'autre borne du générateur impulsionnel haute tension 170. Cette forme de mise en œuvre de l'invention est particulièrement avantageuse car facile à usiner et à assembler. It will also be noted that the body 140, the peripheral electrode 130 and the mold 150 are in electrical contact with each other when they consist of a conductive material such as steel, or any other alloy metallic. In the embodiment described here, an electrical insulator 1 15 surrounds the central electrode 120 over at least part of its length, in particular on the part of the central electrode 120 housed in the body 140. The central electrode 120 is therefore electrically isolated from the peripheral electrode 130, even if the body 140 is in electrical contact with the peripheral electrode 130. The central electrode 120 can therefore be subjected to a first electrical potential by connecting it to one of the terminals a high voltage pulse generator 170 and connecting the body 140, the peripheral electrode 130 or the mold 150 to the other terminal of the pulse generator high voltage 170. This form of implementation of the invention is particularly advantageous because easy to machine and assemble.
On notera que le moule 150 peut être constitué d'un seul tenant ou être fixé sur une pièce supplémentaire appelée support de moule, permettant ainsi de changer plus facilement le moule en fonction de la pièce à former.  Note that the mold 150 may consist of a single piece or be attached to an additional piece called mold support, thus making it easier to change the mold depending on the workpiece.
On notera que les différents éléments constitutifs du dispositif d'électrohydroformage décrits ici sont fixés entre eux à l'aide de vis et que des joints peuvent être utilisés afin d'étanchéifier la chambre d'hydroformage, notamment au niveau de l'électrode centrale, de l'électrode périphérique et du moule par exemple. De tels moyens sont à la portée de l'homme du métier et ne sont pas décrits avec plus de détails ici par soucis de simplification.  It should be noted that the various constituent elements of the electrohydroforming device described here are fastened to one another by means of screws and that seals can be used in order to seal the hydroforming chamber, in particular at the level of the central electrode, of the peripheral electrode and the mold for example. Such means are within the reach of those skilled in the art and are not described in more detail here for the sake of simplification.
On notera par ailleurs que la façon dont est maintenue l'électrode centrale dans le corps n'est pas représentée. L'électrode centrale peut être fixée dans le dispositif d'électrohydroformage par différents moyens. Elle peut, par exemple, être maintenue à l'aide d'une pièce supplémentaire (non représentée) isolée électriquement du corps.  Note also that the way the central electrode is held in the body is not shown. The central electrode can be fixed in the electrohydroforming device by various means. It can, for example, be maintained using an additional piece (not shown) electrically isolated from the body.
De manière avantageuse, afin de pouvoir placer le flan de matière entre l'électrode périphérique et le moule, l'ensemble formé par le moule et l'électrode périphérique est mobile par rapport au corps comprenant l'électrode centrale et le corps est de préférence fixe. L'électrode périphérique est alors fixée sur le moule. Ainsi, il n'est pas nécessaire de déplacer les conducteurs d'amenée du courant reliés au corps lorsque l'on change le flan de matière à déformer.  Advantageously, in order to be able to place the blank of material between the peripheral electrode and the mold, the assembly formed by the mold and the peripheral electrode is movable relative to the body comprising the central electrode and the body is preferably fixed. The peripheral electrode is then fixed on the mold. Thus, it is not necessary to move the current supply conductors connected to the body when changing the blank of material to be deformed.
Dans une variante de réalisation, le moule est monté sur le plateau d'une presse et l'électrode périphérique est fixée directement sur le corps. Le flan de matière est maintenu entre l'électrode périphérique et le moule lorsque le moule est maintenu contre l'électrode périphérique à l'aide de la presse.  In an alternative embodiment, the mold is mounted on the plate of a press and the peripheral electrode is fixed directly on the body. The blank of material is held between the peripheral electrode and the mold when the mold is held against the peripheral electrode with the aid of the press.
On notera que dans les dispositifs d'électrohydroformage décrits ici et dans la présente demande, l'électrode périphérique est facilement accessible et peut être facilement changée.  Note that in the electrohydroforming devices described herein and in the present application, the peripheral electrode is easily accessible and can be easily changed.
La figure 2 représente une deuxième forme de réalisation d'un dispositif d'électrohydroformage selon l'invention. Le dispositif d'électrohydroformage 200 est semblable à celui représenté en référence à la figure 1 A en ce qu'il comprend également une chambre d'électrohydroformage 210, une électrode centrale 220, une électrode périphérique 230, un corps 240 et un moule 250. Contrairement au dispositif d'électrohydroformage représenté en référence à la figure 1A, le dispositif d'électrohydroformage 200 comprend en outre une pièce supplémentaire 280 faisant office de serre-flan. Le dispositif comprend en outre un porte-électrode 232 sur lequel est fixée l'électrode périphérique 230. Le corps 240 comprend en outre un isolant électrique 215 positionné, non plus entre le corps et l'électrode centrale comme illustré en référence aux figures 1A et 1 B, mais par exemple, sur la partie inférieure du corps 240. Dans la forme de réalisation illustrée ici, l'isolant électrique 215 constitue la paroi latérale 243 de la cavité 240 formant en partie la chambre d'électrohydroformage 210. Dans d'autres variantes de réalisation, l'isolant électrique 215 peut ne former qu'une partie de la paroi latérale. L'électrode centrale 220 et la partie supérieure 241 du corps 240 sont alors en contact électrique et la partie supérieure 241 du corps 240, par exemple, peut être reliée à une première borne du générateur impulsionnel haute tension 270. L'électrode périphérique 230, le porte-électrode 232, le serre-flan 280 et le moule 250 sont en contact électrique et l'électrode périphérique 230 est reliée à une seconde borne du générateur impulsionnel haute tension 270 par l'intermédiaire du porte-électrode 232, du serre-flan 280 ou du moule 250 provoquant ainsi une décharge électrique entre l'électrode centrale 220 et l'électrode périphérique 230. L'onde de choc ainsi générée se propage dans un plan perpendiculaire à cette décharge. Ainsi, une partie de l'onde de choc se propage vers la paroi de fond 244 et vient impacter cette paroi, ce qui peut l'endommager. L'isolant étant situé sur la paroi latérale, celui-ci est donc moins sollicité, ce qui diminue son risque d'endommagement. FIG. 2 represents a second embodiment of an electrohydroforming device according to the invention. The electrohydroforming device 200 is similar to that shown with reference to the FIG. 1A in that it also comprises an electrohydroforming chamber 210, a central electrode 220, a peripheral electrode 230, a body 240 and a mold 250. In contrast to the electrohydroforming device represented with reference to FIG. 1A, the electrohydroforming device 200 further comprises an additional piece 280 serving as a blank holder. The device further comprises an electrode holder 232 on which is fixed the peripheral electrode 230. The body 240 further comprises an electrical insulator 215 positioned, either between the body and the central electrode as illustrated with reference to FIGS. 1A and 1B, but for example on the lower part of the body 240. In the embodiment illustrated here, the electrical insulator 215 forms the side wall 243 of the cavity 240 forming part of the electrohydroforming chamber 210. In other alternative embodiments, the electrical insulator 215 may form only part of the side wall. The central electrode 220 and the upper part 241 of the body 240 are then in electrical contact and the upper part 241 of the body 240, for example, can be connected to a first terminal of the high voltage pulse generator 270. The peripheral electrode 230, the electrode holder 232, the blank holder 280 and the mold 250 are in electrical contact and the peripheral electrode 230 is connected to a second terminal of the high voltage pulse generator 270 via the electrode holder 232, the clamp blank 280 or mold 250 thus causing an electric discharge between the central electrode 220 and the peripheral electrode 230. The shock wave thus generated propagates in a plane perpendicular to this discharge. Thus, a portion of the shock wave propagates towards the bottom wall 244 and impacts the wall, which can damage it. The insulation is located on the side wall, it is less stressed, which reduces the risk of damage.
On notera que, comme dans la figure 1A, le corps 240 comprend une cavité 242 et que la paroi latérale 243 et la paroi de fond 244 peuvent avoir différentes formes adaptées à un meilleur confinement des ondes de pression vers le flan de matière à déformer. Par exemple, la paroi de fond 244 peut être inclinée de façon à mieux réfléchir les ondes de choc vers le flan de matière à déformer.  It should be noted that, as in FIG. 1A, the body 240 comprises a cavity 242 and that the side wall 243 and the bottom wall 244 can have different shapes adapted to a better confinement of the pressure waves towards the blank of material to be deformed. For example, the bottom wall 244 may be inclined to better reflect the shock waves to the blank of material to be deformed.
On notera également que la partie active 224 de l'électrode centrale 220 et la partie active 234 de l'électrode périphérique 230 ne sont pas forcément de section constante et/ou axisymétrique comme illustré en référence à la figure 2. It will also be noted that the active part 224 of the central electrode 220 and the active portion 234 of the peripheral electrode 230 are not necessarily of constant section and / or axisymmetric as illustrated with reference to FIG.
Dans les formes de réalisation décrites en référence aux figures 1A, 1 B et 2, les dispositifs d'électrohydroformage ne comportent qu'une électrode centrale et qu'une électrode périphérique.  In the embodiments described with reference to FIGS. 1A, 1B and 2, the electrohydroforming devices comprise only a central electrode and a peripheral electrode.
Dans d'autres formes de réalisation, le dispositif d'électrohydroformage peut comporter plusieurs paires d'électrodes centrales et périphériques associées à un ou plusieurs moules. Il est ainsi possible de réaliser plusieurs pièces en parallèle ou une grande pièce en mettant en œuvre parallèlement plusieurs décharges électriques.  In other embodiments, the electrohydroforming device may comprise several pairs of central and peripheral electrodes associated with one or more molds. It is thus possible to produce several parts in parallel or a large part by implementing several electric discharges in parallel.
Dans le cas de pièces à former de grandes dimensions, il peut être avantageux aussi d'utiliser plusieurs électrodes centrales associées à une unique électrode périphérique. En réalisant plusieurs décharges électriques simultanées ou différées à différents endroits, il est possible de réaliser un formage électrohydraulique plus homogène ou plus progressif ou plus profond.  In the case of pieces to form large dimensions, it may also be advantageous to use a plurality of central electrodes associated with a single peripheral electrode. By performing several simultaneous or delayed electrical discharges at different locations, it is possible to perform a more homogeneous or progressive or deeper electrohydraulic forming.
Différentes formes d'électrodes et différentes dispositions d'électrodes centrales sont illustrées en référence aux figures 3A à 3D.  Different electrode shapes and different central electrode arrangements are illustrated with reference to FIGS. 3A-3D.
Les figures 3A à 3D illustrent plus particulièrement les parties actives d'électrodes centrales et périphériques vues en coupe selon un plan (ΥΥ', ΖΖ') perpendiculaire à l'axe longitudinal XX' d'une électrode centrale.  FIGS. 3A to 3D more particularly illustrate the active portions of central and peripheral electrodes seen in section along a plane (ΥΥ ', ΖΖ') perpendicular to the longitudinal axis XX 'of a central electrode.
Dans la figure 3A, la partie active 301 de l'électrode centrale est de forme circulaire et la partie active 302 de l'électrode périphérique a la forme d'un anneau circulaire.  In FIG. 3A, the active part 301 of the central electrode is of circular shape and the active part 302 of the peripheral electrode has the shape of a circular ring.
Dans la figure 3B, les parties actives 303, 305, 307 de plusieurs électrodes centrales sont de section rectangulaire, de préférence à coins arrondis, et alignées selon une direction commune ZZ' au centre d'un anneau de forme rectangulaire formant la partie active 308 de l'électrode périphérique correspondante.  In FIG. 3B, the active parts 303, 305, 307 of several central electrodes are of rectangular section, preferably with rounded corners, and aligned in a common direction ZZ 'in the center of a ring of rectangular shape forming the active part 308 of the corresponding peripheral electrode.
Dans la figure 3C, les parties actives 309, 31 1 de plusieurs électrodes centrales sont de section elliptique et alignées selon une direction commune ZZ' au centre d'un anneau de forme elliptique formant la partie active 312 de l'électrode périphérique correspondante. Dans la figure 3D, les parties actives 313, 314, 315, 316 de quatre électrodes centrales sont de section rectangulaire carrées, de préférence à coins arrondis, et sont disposées à l'intérieur d'un anneau de forme carrée formant la partie active 317 de l'électrode périphérique correspondante. In FIG. 3C, the active parts 309, 31 1 of a plurality of central electrodes are of elliptical section and aligned in a common direction ZZ 'in the center of an elliptical ring forming the active part 312 of the corresponding peripheral electrode. In FIG. 3D, the active portions 313, 314, 315, 316 of four central electrodes are of square rectangular section, preferably with rounded corners, and are arranged inside a square-shaped ring forming the active part 317. of the corresponding peripheral electrode.
Les électrodes périphériques décrites ici sont formées d'une seule pièce. Dans une variante de réalisation, les électrodes périphériques comportent différents tronçons séparés destinés à être mis en regard de chaque électrode centrale pour générer des décharges. Ces différents tronçons comprennent donc les parties actives de l'électrode périphérique. On diminue ainsi les coûts de remplacement des électrodes périphériques en ne remplaçant que certains tronçons. On notera que d'autres formes géométriques peuvent également être utilisées pour peu que la distance entre la surface externe de la partie active de l'électrode centrale considérée et la surface interne de la partie active de l'électrode périphérique avoisinante soit sensiblement équidistante sur au moins une portion des surfaces des parties actives considérées dans le plan.  The peripheral electrodes described here are formed in one piece. In an alternative embodiment, the peripheral electrodes comprise different separate sections intended to be placed opposite each central electrode to generate discharges. These different sections therefore comprise the active parts of the peripheral electrode. This reduces the cost of replacement of the peripheral electrodes by replacing only certain sections. Note that other geometrical shapes may also be used provided that the distance between the outer surface of the active portion of the central electrode considered and the inner surface of the active portion of the surrounding peripheral electrode is substantially equidistant on the least a portion of the surfaces of the active parts considered in the plane.
Comme discuté précédemment en référence à la figure 2, la section des parties actives des électrodes peut être constante ou varier selon leur direction longitudinale représentée par l'axe XX' sur les figures 1A, 1 B et 2.  As discussed previously with reference to FIG. 2, the section of the active parts of the electrodes may be constant or vary in their longitudinal direction represented by the axis XX 'in FIGS. 1A, 1B and 2.
Les diverses formes de réalisation d'un dispositif d'électrohydroformage décrites ci-dessus permettent le formage électrohydraulique de flans de matière avec une électrode périphérique entourant en partie une électrode centrale, l'électrode périphérique étant distincte du corps formant en partie la chambre d'électrohydroformage. La décharge électrique est donc distribuée sur la périphérie des parties actives des électrodes. L'électrode périphérique, qui possède une plus grande surface de contact, s'use plus lentement. Ainsi, la distance entre les électrodes varie peu, ce qui permet de maintenir l'efficacité de l'électrohydroformage en gardant une pression générée par la décharge électrique sensiblement constante. Toutefois, lorsque les électrodes doivent être changées, l'électrode périphérique peut, de manière avantageuse, facilement être changée lorsque le dispositif d'électrohydroformage est ouvert pour placer le flan de matière, l'électrode périphérique étant distincte du corps et le flan de matière étant préférentiellement placé entre l'électrode périphérique et le moule. De manière avantageuse, l'électrode centrale peut être déplacée selon son axe longitudinal afin de présenter à l'électrode périphérique une partie active moins dégradée. The various embodiments of an electrohydroforming device described above allow the electrohydraulic forming of blanks of material with a peripheral electrode partially surrounding a central electrode, the peripheral electrode being distinct from the body forming in part the chamber of électrohydroformage. The electric discharge is distributed over the periphery of the active parts of the electrodes. The peripheral electrode, which has a larger contact area, wears more slowly. Thus, the distance between the electrodes varies little, which keeps the efficiency of electrohydroforming by keeping a pressure generated by the substantially constant electric discharge. However, when the electrodes are to be changed, the peripheral electrode may advantageously be easily changed when the electrohydroforming device is open to place the blank of material, the peripheral electrode being distinct from the body and the blank of material being preferentially placed between the peripheral electrode and the mold. Advantageously, the central electrode may be displaced along its longitudinal axis in order to present to the peripheral electrode a less degraded active part.
La présente invention ne se limite pas aux différentes formes de réalisation décrites et illustrées et aux variantes évoquées mais elle concerne également les formes de réalisation à la portée de l'homme du métier dans le cadre des revendications ci-après.  The present invention is not limited to the various embodiments described and illustrated and the variants mentioned but it also relates to the embodiments within the scope of the skilled person within the scope of the claims below.

Claims

REVENDICATIONS
1. Dispositif d'électrohydroformage (100 ; 100' ; 200) d'un flan de matière (160 ; 260) comprenant : An electrohydroforming device (100; 100 '; 200) of a blank of material (160; 260) comprising:
- une chambre d'électrohydroformage (1 10 ; 210),  an electrohydroforming chamber (1 10; 210),
- au moins une électrode dite électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316) s'étendant selon une direction dite longitudinale (XX') et comportant une première extrémité (122) disposée à l'intérieur de la chambre d'électrohydroformage (1 10 ; 210),  at least one so-called central electrode electrode (120; 220; 301; 303; 305; 307; 309; 31; 313; 314; 315; 316) extending in a so-called longitudinal direction (XX ') and comprising a first end (122) disposed within the electrohydroforming chamber (1 10; 210),
- au moins une électrode dite électrode périphérique (130 ; 230 ; 302, at least one so-called peripheral electrode (130; 230; 302,
308, 312, 317) électriquement isolée de chaque électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316), présentant une extrémité (132) disposée à distance et autour de l'extrémité (122) d'une électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316), ladite extrémité (132) s'étendant dans un plan transversal (ΥΥ', ΖΖ') par rapport à ladite électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316), 308, 312, 317) electrically isolated from each central electrode (120; 220; 301; 303; 305; 307; 309; 31; 313; 314; 315; 316) having an end (132) disposed at a distance and around the end (122) of a central electrode (120; 220; 301; 303; 305; 307; 309; 31; 313; 314; 315; 316), said end (132) extending in a plane transverse (ΥΥ ', ΖΖ') with respect to said central electrode (120; 220; 301, 303, 305, 307, 309, 31 1, 313, 314, 315, 316),
- un corps (140 ; 240) muni d'un alésage pour l'introduction de chaque électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316) dans la chambre d'électrohydroformage (1 10 ; 210), la chambre d'électrohydroformage (1 10 ; 210) étant en partie formée par ledit corps (140 ; 240), et  a body (140; 240) having a bore for introducing each central electrode (120; 220; 301; 303; 305; 307; 309; 31; 313; 314; 315; 316) into the chamber; electrohydroforming apparatus (110; 210), the electrohydroforming chamber (110; 210) being partially formed by said body (140; 240), and
- un moule (150 ; 250),  a mold (150; 250),
caractérisé en ce que chaque électrode périphérique (130 ; 230 ; 302, 308, 312, 317) est distincte dudit corps (140 ; 240).  characterized in that each peripheral electrode (130; 230; 302; 308; 312,317) is distinct from said body (140; 240).
2. Dispositif (100 ; 100' ; 200) selon la revendication 1 , caractérisé en ce que l'au moins une électrode périphérique (130 ; 230 ; 302, 308, 312, 317) est en saillie par rapport au corps (140 ; 240). 2. Device (100; 100 '; 200) according to claim 1, characterized in that the at least one peripheral electrode (130; 230; 302; 308; 312,317) projects from the body (140; 240).
3. Dispositif (100' ; 200) selon la revendication 1 ou 2, caractérisé en ce que l'au moins une électrode périphérique (130 ; 230 ; 302, 308, 312, 317) est supportée par un porte-électrode (136 ; 232). 3. Device (100 ', 200) according to claim 1 or 2, characterized in that the at least one peripheral electrode (130; 230; 302; 308; 312,317) is supported by an electrode holder (136; 232).
4. Dispositif (100, 100' ; 200) selon l'une des revendications précédentes, caractérisé en ce que le dispositif (100 ; 200) comporte une unique électrode périphérique (130 ; 230 ; 302, 308, 312, 317) et au moins une électrode centrale (120 ; 220 ; 301 , 303, 305, 307, 309, 31 1 , 313, 314, 315, 316). 4. Device (100, 100 ', 200) according to one of the preceding claims, characterized in that the device (100; 200) comprises a single peripheral electrode (130; 230; 302, 308, 312, 317) and at least one central electrode (120; 220; 301, 303, 305, 307, 309, 31 1, 313, 314, 315, 316).
5. Dispositif (100 ; 100' ; 200) selon l'une des revendications précédentes, caractérisé en ce que la chambre d'électrohydroformage (1 10 ; 210) est formée par un corps (140 ; 240) et par l'extrémité (132) de l'électrode périphérique (130). 5. Device (100; 100 '; 200) according to one of the preceding claims, characterized in that the electrohydroforming chamber (1 10; 210) is formed by a body (140; 240) and by the end ( 132) of the peripheral electrode (130).
6. Dispositif (100 ; 100') selon l'une des revendications précédentes, caractérisé en ce que l'électrode centrale (120) est entourée sur une partie de sa longueur par un isolant électrique (1 15). 6. Device (100; 100 ') according to one of the preceding claims, characterized in that the central electrode (120) is surrounded over a portion of its length by an electrical insulator (1 15).
7. Dispositif (200) selon l'une des revendications 1 à 5, caractérisé en ce que le corps (240) est en contact électrique avec l'électrode centrale (220) et comprend en outre un isolant électrique (215) destiné à isoler l'électrode périphérique (230) de l'électrode centrale (220). 7. Device (200) according to one of claims 1 to 5, characterized in that the body (240) is in electrical contact with the central electrode (220) and further comprises an electrical insulator (215) for isolating the peripheral electrode (230) of the central electrode (220).
8. Dispositif (200) selon la revendication 7, caractérisé en ce que le corps (240) comporte en outre une cavité (242) formant en partie la chambre d'électrohydroformage (210) et en ce que l'isolant électrique (215) forme au moins en partie une paroi latérale (243) de ladite cavité (242). 8. Device (200) according to claim 7, characterized in that the body (240) further comprises a cavity (242) partly forming the electrohydroforming chamber (210) and in that the electrical insulator (215) at least partially forms a side wall (243) of said cavity (242).
9. Dispositif (200) selon la revendication 8, caractérisé en ce que l'isolant électrique (215) constitue la paroi latérale (243) de la cavité (242). 9. Device (200) according to claim 8, characterized in that the electrical insulator (215) constitutes the side wall (243) of the cavity (242).
10. Dispositif (100 ; 200) selon l'une des revendications précédentes, caractérisé en ce que le dispositif (100 ; 200) comporte en outre un support de moule. 10. Device (100; 200) according to one of the preceding claims, characterized in that the device (100; 200) further comprises a mold support.
11. Dispositif (100 ; 200) selon l'une des revendications précédentes, caractérisé en ce qu'un flan de matière (160 ; 260) est maintenu entre l'extrémité (132) de l'électrode périphérique (130 ; 230) et le moule (150 ; 250). 11. Device (100; 200) according to one of the preceding claims, characterized in that a blank of material (160; 260) is held between the end (132) of the peripheral electrode (130; 230) and the mold (150; 250).
12. Dispositif (200) selon l'une des revendications précédentes, caractérisé en ce que le dispositif (200) comprend un serre-flan (280) disposé entre l'extrémité de l'électrode périphérique (230) et le moule (250). 12. Device (200) according to one of the preceding claims, characterized in that the device (200) comprises a blank holder (280) disposed between the end of the peripheral electrode (230) and the mold (250). .
13. Dispositif (100 ; 200) selon l'une des revendications précédentes, caractérisé en ce que l'extrémité (132) de l'électrode périphérique (130 ; 230) et le moule (150 ; 250) sont en contact électrique et soumis à un premier potentiel électrique, l'électrode centrale (120 ; 220) étant soumise à un second potentiel électrique. 13. Device (100; 200) according to one of the preceding claims, characterized in that the end (132) of the peripheral electrode (130; 230) and the mold (150; 250) are in electrical contact and subjected at a first electric potential, the central electrode (120; 220) being subjected to a second electric potential.
EP18703599.3A 2017-02-08 2018-02-08 Electrohydraulic forming device Active EP3579990B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR1751053A FR3062586B1 (en) 2017-02-08 2017-02-08 ELECTROHYDROFORMING DEVICE
PCT/EP2018/053214 WO2018146216A1 (en) 2017-02-08 2018-02-08 Electrohydraulic forming device

Publications (2)

Publication Number Publication Date
EP3579990A1 true EP3579990A1 (en) 2019-12-18
EP3579990B1 EP3579990B1 (en) 2020-10-14

Family

ID=58707742

Family Applications (1)

Application Number Title Priority Date Filing Date
EP18703599.3A Active EP3579990B1 (en) 2017-02-08 2018-02-08 Electrohydraulic forming device

Country Status (6)

Country Link
US (1) US11338346B2 (en)
EP (1) EP3579990B1 (en)
JP (1) JP7083176B2 (en)
CN (1) CN110582360B (en)
FR (1) FR3062586B1 (en)
WO (1) WO2018146216A1 (en)

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4068514A (en) * 1976-07-12 1978-01-17 Viktor Nikolaevich Chachin Device for electrohydraulic die-forging
RU2060077C1 (en) * 1992-09-02 1996-05-20 Волгоградский государственный технический университет Method of electrohydraulic pulse deformation of tubular blanks
JP4944322B2 (en) * 2001-09-26 2012-05-30 本田技研工業株式会社 Method for manufacturing hollow member
US7802457B2 (en) 2008-05-05 2010-09-28 Ford Global Technologies, Llc Electrohydraulic forming tool and method of forming sheet metal blank with the same
US8567223B2 (en) * 2009-09-21 2013-10-29 Ford Global Technologies, Llc Method and tool for expanding tubular members by electro-hydraulic forming
FR3000909B1 (en) * 2013-01-11 2015-05-15 Adm28 S Ar L METHOD, TOOLING AND PRESS FOR FORMING A PIECE
FR3013243B1 (en) * 2013-11-15 2016-01-01 Adm28 S Ar L ELECTRO-HYDROFORMING DEVICE
TW201600310A (en) * 2014-06-17 2016-01-01 Univ Nat Kaohsiung 1St Univ Sc Drawing die provided with slant blank clamping surface
FR3031054B1 (en) * 2014-12-29 2017-01-27 Adm28 S Ar L ELECTRO-HYDROFORMING DEVICE WITH OPTIMIZED CHAMBER
CN104785605B (en) * 2015-03-31 2017-04-19 西北工业大学 Electro-hydraulic forming device for pipe fitting and forming method

Also Published As

Publication number Publication date
JP7083176B2 (en) 2022-06-10
FR3062586A1 (en) 2018-08-10
CN110582360A (en) 2019-12-17
US11338346B2 (en) 2022-05-24
US20200001344A1 (en) 2020-01-02
JP2020506809A (en) 2020-03-05
CN110582360B (en) 2020-12-04
FR3062586B1 (en) 2020-02-28
WO2018146216A1 (en) 2018-08-16
EP3579990B1 (en) 2020-10-14

Similar Documents

Publication Publication Date Title
EP2943297B1 (en) Method, tool and press for the electrohydraulic forming of a workpiece
WO2016107927A1 (en) Chamber for electrohydraulic forming
CA2925503C (en) Spark-gap of an electric arc generation device, and corresponding electric arc generation device
EP3579990B1 (en) Electrohydraulic forming device
EP3134604B1 (en) Probe for generating seismic waves
FR3058655B1 (en) ELECTROHYDRAULIC FORMING METHOD AND DEVICE THEREOF
EP3047551B1 (en) Spark-gap of an electric arc generation device, and corresponding electric arc generation device
EP3240650B1 (en) Electrohydraulic forming apparatus
FR2987288A1 (en) HEAD OF AN ELECTROHYDRAULIC WIRE DISCHARGE DEVICE
FR3058654B1 (en) ELECTROHYDRAULIC FORMING METHOD AND DEVICE THEREOF
EP3496876B1 (en) Indirect electrohydraulic press forming tool, device and method
EP3720626B1 (en) Methods for shaping/welding parts by means of magnetic pulse
FR3032059A1 (en) CIRCUIT BREAKER EQUIPPED WITH AN EXTENDABLE EXHAUST HOOD
EP3240648B1 (en) Electrohydraulic forming device comprising an optimised chamber
FR2933321A1 (en) Electro-hydraulic machine-tool electrode for shaping e.g. metal tube, has conducting element, where non-insulated part of element and uncovered parts of insulator layer and material layer permit passage of electrical discharge within fluid
FR3086565A1 (en) PROCESS FOR TREATING A POROUS PART
CH532832A (en) Pair of Electrodes for vacuum electric discharge

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

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

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

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

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

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20190724

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

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

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20200625

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

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

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1323074

Country of ref document: AT

Kind code of ref document: T

Effective date: 20201015

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602018008737

Country of ref document: DE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: FRENCH

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1323074

Country of ref document: AT

Kind code of ref document: T

Effective date: 20201014

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20201014

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

Ref country code: RS

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: 20201014

Ref country code: PT

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: 20210215

Ref country code: FI

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: 20201014

Ref country code: NO

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: 20210114

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: 20210115

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20201014

Ref country code: ES

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: 20201014

Ref country code: BG

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: 20210114

Ref country code: PL

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: 20201014

Ref country code: LV

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: 20201014

Ref country code: IS

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: 20210214

Ref country code: SE

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: 20201014

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: 20201014

Ref country code: HR

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: 20201014

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602018008737

Country of ref document: DE

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

Ref country code: EE

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: 20201014

Ref country code: CZ

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: 20201014

Ref country code: SK

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: 20201014

Ref country code: SM

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: 20201014

Ref country code: RO

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: 20201014

Ref country code: LT

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: 20201014

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

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

Ref country code: DK

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: 20201014

26N No opposition filed

Effective date: 20210715

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

Ref country code: MC

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: 20201014

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20210228

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

Ref country code: CH

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

Effective date: 20210228

Ref country code: AL

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: 20201014

Ref country code: LI

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

Effective date: 20210228

Ref country code: LU

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

Effective date: 20210208

Ref country code: IT

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: 20201014

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

Ref country code: SI

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: 20201014

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

Ref country code: IE

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

Effective date: 20210208

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

Ref country code: IS

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: 20210214

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

Ref country code: BE

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

Effective date: 20210228

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

Ref country code: FR

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

Effective date: 20220228

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

Ref country code: FR

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

Effective date: 20220228

PGRI Patent reinstated in contracting state [announced from national office to epo]

Ref country code: FR

Effective date: 20230120

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

Ref country code: CY

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: 20201014

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

Ref country code: HU

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

Effective date: 20180208

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

Ref country code: FR

Payment date: 20231228

Year of fee payment: 7

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

Ref country code: MK

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: 20201014

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

Ref country code: DE

Payment date: 20240213

Year of fee payment: 7

Ref country code: GB

Payment date: 20240221

Year of fee payment: 7