WO2013057550A2 - Procédé d'aiguisage et aiguiseur pour une lame à biseau unique - Google Patents

Procédé d'aiguisage et aiguiseur pour une lame à biseau unique Download PDF

Info

Publication number
WO2013057550A2
WO2013057550A2 PCT/IB2012/001885 IB2012001885W WO2013057550A2 WO 2013057550 A2 WO2013057550 A2 WO 2013057550A2 IB 2012001885 W IB2012001885 W IB 2012001885W WO 2013057550 A2 WO2013057550 A2 WO 2013057550A2
Authority
WO
WIPO (PCT)
Prior art keywords
blade
substantially flat
abrasive surface
flat abrasive
sharpening
Prior art date
Application number
PCT/IB2012/001885
Other languages
English (en)
Other versions
WO2013057550A3 (fr
Inventor
Mark James Henry
Original Assignee
De Buyer Industries
Mj Henry Group, Inc.
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 De Buyer Industries, Mj Henry Group, Inc. filed Critical De Buyer Industries
Publication of WO2013057550A2 publication Critical patent/WO2013057550A2/fr
Publication of WO2013057550A3 publication Critical patent/WO2013057550A3/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D15/00—Hand tools or other devices for non-rotary grinding, polishing, or stropping
    • B24D15/06—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges
    • B24D15/08—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges of knives; of razors
    • B24D15/084—Hand tools or other devices for non-rotary grinding, polishing, or stropping specially designed for sharpening cutting edges of knives; of razors the sharpening elements being fitted to knife sheaths, holders or handles

Definitions

  • the present invention relates to a sharpening method and blade sharpener particularly for single-bevel blades.
  • a chisel-edged blade or single-bevel blade, having an edge bevel on one side of the blade only and a nominally flat opposing side, in the Japanese blade tradition, generally possesses superior cutting performance when compared with more common two- bevelled, symmetrical cutting edges in the Western European-American blade tradition.
  • Such chisel-edged blades are ground with a major bevel on one side and a nominally flat or slightly concave surface on the opposite side.
  • the present invention combines a single bevel "chisel" edge blade of specific geometry and a flat abrasive and/or polishing surface. In this manner, a chisel-edged blade can be maintained not by skill-intensive whetstone sharpening of the chisel edge alone, but instead primarily by constant light honing of the flat back face. DESCRIPTION OF THE PREFERRED EMBODIMENTS
  • a subject of the present application is therefore a method for sharpening a blade comprising:
  • the substantially flat abrasive surface can be used as a honing/storage device if the said substantially flat abrasive surface is mounted to any stable object (bench, wall, wood block, frame, etc).
  • the plate may be used alone and may include mounting holes, lugs or magnets for attachment to an appropriate surface in a professional kitchen, meatworks, a butcher, food processing operations, a home kitchen, etc.
  • the blade sharpener is comprised in a blade or knife storage device.
  • the storage device may be a block having openings for multiple blades, a scabbard, or an open mechanism adapted to be attached to a wall or cupboard.
  • a block or scabbard having openings is preferred.
  • the sliding motion occurs preferably naturally in the same action of sliding the knife into its storage position and sliding it back out of the storage device.
  • the substantially flat abrasive surface of the blade sharpener may be of any material that has an ability to hone or lap the substantially flat back surface of the cutting edge of the blade whenever the blade and flat plate are moved in a sliding motion in relation to each other.
  • a sharpening plate (or a deburring tool or bearing guide) according to the present invention may be formed of any one or more of the following materials: magnetic or non-magnetic stainless steel (regular annealed austenitic or ferritic alloys); magnetic or non-magnetic hardened and tempered stainless steel alloys; titanium alloys; ceramic; ceramic-metallic composites such as tungsten carbide; natural or synthetic abrasive stone; natural or synthetic diamond or gemstone-coatings on a supporting base plate or plates, or on another object or objects; and any other material capable of polishing, honing or lapping a blade material.
  • Such materials are preferably readily available, inexpensive and effective for a honing or sharpening abrasive action, particularly stainless steel alloys, ceramics, industrial diamond coatings.
  • the substantially flat abrasive surface of the blade sharpener may be integral or not.
  • the average surface may comprise successive blocks of different materials affixed to the plate mechanically, either solidly, or floating, to ensure constant contact with the cutting edge during the sliding motion described herein.
  • the substantially flat abrasive surface may be slightly concave to improve honing efficiency.
  • a very shallow concave surface concept may optionally be utilized to enhance the ability of the abrasive surface to focus the sharpening/honing/lapping action on the very edge of the cutting edge of a blade.
  • a blade used in the present method can be flat or even slightly convex, as long as the cutting edge makes contact with the substantially flat abrasive surface along its length. This may be possible even with a slightly convex blade, if the substantially flat abrasive surface is sufficiently concave to compensate for the convex shape.
  • the substantially flat abrasive surface is concave and the back side of the blade is flat.
  • lightly concave is meant a radius of curvature of the concavity of of 7.0 m to 0.1 m, preferably of 2.0 m to 0.2 m, most preferably of 1 .5 m to 0.5 m and, most importantly in practise, to ensure the tip of the cutting edge remains in contact with the abrasive element.
  • a convex guiding member or convex blade may abrade the side of the blade instead of the very cutting edge, and efficacy of the invention would be reduced. .
  • the same values apply for "slightly convex”.
  • the radius of curvature need not correspond to a circle of constant radius.
  • the center of the curvature radius can be less than the radius of curvature of the edges.
  • the substantially flat abrasive surface has a surface of sufficient area to contact the cutting edge constantly during the sliding motions of placing and removing the blade, generally of more than 2 cm 2 , preferably of 3 to 600 cm 2 , particularly of 5 to 400 cm 2 .
  • the surface refers to the sum of the individual surfaces.
  • Knives which are chisel ground come in left and right-handed varieties, depending upon which side is ground and are often sharper than a typical double bevelled Western culinary knife. Japanese use such blades widely in their kitchen knives, though they are rarely used in the West.
  • the flat face of the blade which is the back side of the blade named "Urasuki" in Japan may be slightly concave. When the back side of the blade is concave, the drag and adhesion during cutting is reduced so the food separates more cleanly, with less blade force.
  • a single-bevel blade may be formed of any one or more of the following materials: hardened and tempered stainless steel alloys; titanium alloys; ceramic; ceramic-metallic composites such as tungsten carbide; any other hardenable metal; and any other hard and tough material suitable for holding a reasonable edge and performing cutting tasks.
  • Some force normal to the surfaces is required for abrasion, whereby the blade and the substantially flat abrasive surface are pressed together in flat contact with each other during the sliding action, and this may be achieved with a variety of mechanical or magnetic means.
  • Mechanical means include for example a leaf spring or spring guiding elements pressing the blade against the plate, for instance rollers, guides, etc.
  • Magnetic means include for example magnetically charged plate and/or blade, magnets behind or embedded in a plate or a blade.
  • the whole plate is magnetized creating an attractive force sufficient to create pressure between a blade and the substantially flat abrasive surface.
  • Button or bar magnets may be used to create a variable force that may be adjusted by user or a professional customizing a sharpening device according to the present method. Individual magnets may be moved or used in different numbers to adjust the force to an ideal amount.
  • mechanical or magnetic means may push the blade against the substantially flat abrasive surface, or the flat abrasive surface towards the blade.
  • mechanical or magnetic means may push the blade against the substantially flat abrasive surface, or the flat abrasive surface towards the blade.
  • leaf springs or helicoidal springs or sprung guides may be provided behind the substantially flat abrasive surface, on the side opposite to the blade 2, or to press on the chisel side of the blade (opposite to the flat side).
  • the blade sharpener may include additional elements for guiding the top or the bottom of the blade or both.
  • small 'burrs' formed on the single bevel side can be automatically removed by any appropriate mechanical mechanism that applies a light abrasion to that chisel edge, at an appropriate angle. For example, this can be achieved with a rod or plate of any hard material set at an angle slightly greater than the final bevel of the final chisel edge, and pressed relatively lightly against the cutting edge by any common mechanical or magnetic means.
  • the de- burring fixture may operate whenever the blade is slid into and out of storage, or only intermittently as required, for example, with a retractable de-burring element.
  • the de-burring element may pivot on a pin, move on a slide, and/or be held in contact by springs, levers, magnets, etc.
  • the de-burring element may rotate or be fixed, and/or be retractable or in a fixed position. Retraction of the de-burring element may be by conventional methods.
  • the blade sharpener includes additional elements for de- burring the chisel cutting edge.
  • the blade sharpener includes bearing guides that assist in guiding the blade into contact with the flat plate.
  • the cutting edge may typically not contact the bearing guides, which will typically be spaced from the flat plate by a small distance.
  • a bearing guide preferably the first bearing guide at an entrance of the blade sharpener, may alternatively or additionally be used as a de-burring tool.
  • said bearing guide may be angled, from a top perspective, so that the cutting edge contacts it at an angle slightly greater than the final cutting edge angle.
  • the blade sharpener includes a different section or mechanism at the front of the substantially flat abrasive surface, at the point of initial contact with a knife being stored or inserted.
  • the substantially flat abrasive surface has an additional honing or sharpening feature integral with or mounted on or near a leading edge of the substantially flat abrasive surface.
  • the additional sharpening mechanism may additionally or alternatively be simply a raised ridge extending along some or all of the width of the leading edge of the substantially flat abrasive surface.
  • a different material or coating on the substantially flat abrasive surface near the leading edge may be used, or alternatively a separate component of any material may be used.
  • the separate component may be rigidly attached or may be coupled to the substantially flat abrasive surface to allow some movement so that the substantially flat abrasive surface "floats" to ensure reliable contact with the flat backside of the blade.
  • the substantially flat abrasive surface is comprised in a blade or knife storage device and the additional honing or sharpening feature is a sharpening member hinged on the stationary blade storage device for allowing the pivoting of the sharpening member.
  • the sharpening member comprises a single or a plurality of pivoting inflexible abrasive elements.
  • the sharpening member or members cooperate with the substantially flat abrasive surface for providing a groove having abrasive faces and are operable to engage the cutting edge on the chisel side of the blade.
  • a subject of the present invention is also a blade sharpener comprising a substantially flat abrasive surface and means for pressing a blade against the substantially flat abrasive surface.
  • the substantially flat back face of the blade is lightly honed or lapped.
  • a sharpening device may be mounted anywhere.
  • a sharpening plate may be mounted to a wall or other fixture, for instance a cupboard or bench.
  • the control of the blade position with respect to the sharpening plate may be achieved by the shape and position of the storage device opening and/or the additional magnetic or mechanical elements, and in this manner, the proper sharpening angle may be created.
  • the mounting plate including positioning elements may be used as a stand-alone sharpening system, and may in some exemplary embodiments not be used for storage of a knife.
  • the present invention provides constant maintenance of a sharp cutting edge through honing/lapping generated by the sliding action of simple knife storage and retrieval. Only in extreme circumstances, for example, when the blade is used on a very abrasive cutting surface, is the honing and lapping action of the flat plate not likely able to keep pace with the rate of wear of the cutting edge. In such cases, the blade may be either conventionally sharpened on stones or similar abrasive devices on the chisel edge side.
  • a dulled chisel-edge blade may be sharpened on the flat back face with a more abrasive version of the present invention, or on conventional stones and the like.
  • the present invention may be equipped with abrasive elements acting on the chisel edge constantly, or intermittently, when required, to also maintain sharpness of the chisel side of the blade.
  • Figure 1 represents a side view of a Japanese styling single bevel knife located in contact with a blade sharpener comprising a substantially flat abrasive surface
  • Figures 2 and 3 represent two longitudinal cross sections of possible chisel edge blades
  • Figure 4 is a front view of Figure 1 .
  • Figure 5 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention provided with a leaf spring
  • Figure 6 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention provided with magnets
  • Figure 7 represents a perspective view of a Japanese styling single bevel knife inserted into a sheath provided with a substantially flat abrasive surface of the present invention
  • Figure 8 is a front view similar to Figure 4, wherein the substantially flat abrasive surface is concave,
  • Figure 9 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention provided with two short successive abrasive surfaces
  • Figure 10 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention further provided with a hinged sharpening member and a sheath.
  • Figure 1 1 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention further provided with a hinged sharpening member.
  • Figure 12 represents a blank of flat metal prepared for providing a blade sharpener and Figure 13 represents a same blank of which some strips have been bent.
  • Figure 1 shows a Japanese style single bevel knife comprising a handle 1 and a blade 2.
  • the knife provided with a cutting edge 7 is located in contact with a blade sharpener 3 comprising a substantially flat abrasive surface 4.
  • Figure 2 represents the longitudinal cross section of a chisel edge blade 2 provided with a flat back side 5.
  • the back side 5 and the front side 6 are substantially parallel.
  • the cutting edge 7 is provided at the bottom beveled side of the blade.
  • Figure 3 is a modification of the blade of figure 2, wherein the back side 5 and the front side 6 are substantially parallel but the back side 5 is concave.
  • Figure 4 is a front view of Figure 1 , showing the back side 5 of the blade 2 located in contact with the flat abrasive surface 4.
  • Figure 5 represents a perspective view of a blade 2 of a single bevel knife located in contact with a flat abrasive surface 4 of a blade sharpener of the invention provided with a leaf spring 10.
  • the leaf spring 10 pushes the blade against the flat abrasive surface 4 such that sliding the substantially flat back surface of the blade onto and along the flat abrasive surface 4 as shown by the arrows, allows honing the blade 2.
  • the cutting edge 7 is guided by a series of rollers 1 1 .
  • the blade sharpener of figure 5 is usually inserted into a sheath as represented in figure 7, such that the mechanism is invisible to the user.
  • the blade sharpener of figure 5 is further provided with a de-burring element 12 which, in this example, is a rod of hard material set at an angle slightly greater than the bevel of the final chisel edge, automatically removing small burrs possibly formed on the chisel or single bevel side.
  • Deburring element 12 applies a light abrasion to the chisel side of the edge, at an appropriate angle. Deburring element 12 is pressed lightly against the cutting edge by a spring 13 and operates whenever the blade is slid into and out of storage.
  • the blade sharpener of the embodiment of Figure 6 is provided with button magnets 14 which attract the blade 2 against the flat abrasive surface 4.
  • Button magnets may be used to create a variable force that may be adjusted by user or a professional customizing a sharpening device according to the present method. Button magnets may be moved or used in different numbers to adjust the force to an ideal amount for the desired sharpening/honing efficacy.
  • the back side 5 of the blade is concave. Arrangements similar to those of figure 5 may be provided to this embodiment.
  • Figure 7 represents a typical commercial blade sharpener of the invention.
  • the blade sharpener is included in a case which is a sheath 20 usually made of wood, plastic material or metal.
  • the sheath 20 is provided with a passageway having an entrance slot 21 allowing introduction of the blade 2 of a knife into the sheath 20.
  • the passageway has inner walls and guides the blade such that honing occurs.
  • Devices for pushing the blade onto the flat abrasive surface 4 may be provided on the sheath 20 itself.
  • the width of the passageway is adjusted such that the blade is pushed onto the flat abrasive surface without specific device, by an inner wall or other guiding element of the sheath 20.
  • the depth of the passageway is sufficient for allowing complete insertion of a blade into the sheath.
  • Different sizes of sheaths may be provided according to the size of the blade.
  • the flat abrasive surface 4 installed in the sheath 20 is pushed towards the blade 2 by helicoidal springs provided between the inner wall of the sheath 20 facing the backside of the blade 2 and the flat abrasive surface 4.
  • the blade pushes the flat abrasive surface 4 away.
  • the elements may also be reversed, with the flat abrasive surface fixed, and the blade pressed against it.
  • a hinged sharpening member or members 30 provided at the bottom of the scabbard slot like the one shown in Figure 1 1 .
  • the hinged sharpening member 30 may be the only one in the scabbard, or the only one visible of several sharpening members.
  • Figure 8 is a front view similar to Figure 4, wherein the substantially flat abrasive surface is concave.
  • the concavity is represented by an arc of a circle.
  • a concavity in the flat plate used to sharpen knives improves the sharpening ability of the device, system and method according to the present invention.
  • the illustration of this concavity shows a highly exaggerated concavity.
  • the actual concavity would be smaller, in a range of a maximum depth of 0.1 mm to 2.0mm relative to a line joining the top and the bottom sides of the flat abrasive surface 4 facing the flat backside 5 of a blade.
  • a concave flat abrasive surface is usually used with blades having a flat backside such as represented in Figure 2.
  • a flat abrasive surface is usually used with blades having a concave backside 5 such as represented in Figure 3.
  • a blade can be flat or even convex, as long as the cutting edge makes contact with the plate along its length. This may be possible even with a convex blade, if the plate is sufficiently concave to compensate.
  • Such a combination of means eliminates the higher cost of concave blade grinding and instead shifts the concave to the plate, which is much easier to press with the necessary concave shape to make it work with a nominally flat blade. Therefore lower cost knives may be obtained.
  • the concavity has the same shape throughout the length of the flat abrasive surface.
  • the flat abrasive surface 4 had a length similar to that of the corresponding blade 2.
  • figure 9 represents an embodiment wherein the flat abrasive surface represents only a part of the length of the blade 2 with which it is used.
  • the flat abrasive surface 4 is comprised of two different abrasive materials provided as two adjacent parallelepipedic flat blocks fixed onto a support 22 which is in this embodiment an inner wall of a sheath (the remaining part of the sheath is a casing not represented in this figure), at the entrance of the passageway, such that upon introduction of the blade into the sheath and removal of the blade, the whole length of the backside of a blade is scraped against the abrasive elements.
  • the blade 2 is in an almost fully withdrawn position either being withdrawn or re-stored.
  • FIG 10 represents a perspective view of a blade of a single bevel knife located in contact with a blade sharpener of the invention further provided with a hinged sharpening member.
  • a hinged sharpening member 30 having a pin 31 providing a hinge axis 32 (not represented in this figure) is fastened to a stationary part of the sheath (not represented in this figure) facing the front side 6 of the blade 2.
  • the hinged sharpening member 30 may pivot about the pin 31 . Therefore an additional honing is provided by the hinged sharpening member 30.
  • the cutting edge 7 is therefore provided with a second bevel, the first one being provided by the flat abrasive surface 4.
  • the hinged sharpening member 30 also functions as a de- burring element.
  • the hinged sharpening member 30 preferably comprises several rigid abrasive elements, particularly parallel plates, optionally interleaved with corresponding holes provided in the flat abrasive surface 4.
  • Figure 1 1 represents a perspective view similar to the view of figure 10, but the sheath 33 and the hinge axis 32 have been represented.
  • Figure 12 represents a blank 40 of flat metal provided with a number of aligned holes 41 .
  • This blank is a future sharpener of the invention.
  • the blank is provided with two strips 42, 43 which are to be bent.
  • the blank is further provided with a number of tongues 44 which also are to be bent.
  • the central part of one face of the blank i.e. the part of the blank which will not be bent constitutes a flat abrasive surface 4 of the invention.
  • Such a blade sharpener of the invention which may be used in the above methods is particularly easy and simple to manufacture from a blank of metal.
  • these blade sharpeners may be included in any suitable mounting device such as a scabbard, a holster, a protective case or a knife block.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

L'invention concerne un procédé d'aiguisage d'une lame (2) comprenant les étapes consistant à : - prendre un aiguiseur comportant une surface abrasive (4) sensiblement plane et, - prendre une lame (2) à biseau unique de style japonaise comportant une surface arrière (5) sensiblement plane et un tranchant (7), - prendre des moyens (10, 14) pour presser la lame (2) contre la surface abrasive (4) sensiblement plane et - faire glisser la surface arrière (5) sensiblement plane de la lame (2) sur et le long de la surface abrasive (4) sensiblement plane, pour affûter la lame (2). L'invention concerne également un aiguiseur comportant une surface abrasive (4) sensiblement plane et des moyens (10, 14) pour presser une lame contre la surface abrasive (4) sensiblement plane, et un aiguiseur comportant une surface abrasive (4) sensiblement plane et des moyens (10, 14) pour presser une lame contre la surface abrasive (4) sensiblement plane.
PCT/IB2012/001885 2011-10-21 2012-08-31 Procédé d'aiguisage et aiguiseur pour une lame à biseau unique WO2013057550A2 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US201161549804P 2011-10-21 2011-10-21
US61/549804 2011-10-21
US201161565190P 2011-11-30 2011-11-30
US61/565190 2011-11-30

Publications (2)

Publication Number Publication Date
WO2013057550A2 true WO2013057550A2 (fr) 2013-04-25
WO2013057550A3 WO2013057550A3 (fr) 2013-07-11

Family

ID=47178217

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2012/001885 WO2013057550A2 (fr) 2011-10-21 2012-08-31 Procédé d'aiguisage et aiguiseur pour une lame à biseau unique

Country Status (1)

Country Link
WO (1) WO2013057550A2 (fr)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH188675A (de) * 1936-01-03 1937-01-15 Friedrich Victor Messerbank zum Schärfen von Messern.
US3676961A (en) * 1969-05-07 1972-07-18 Wiltshire Cutlery Co Pty Knife scabbard or holder
IL148599A0 (en) * 2002-03-10 2002-09-12 Gotit Ltd Sharpening apparatus
US7334339B2 (en) * 2002-10-11 2008-02-26 Miltner Richard H Folding knives

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None

Also Published As

Publication number Publication date
WO2013057550A3 (fr) 2013-07-11

Similar Documents

Publication Publication Date Title
US10124458B2 (en) Cutting tool sharpener
US9833880B1 (en) Hand-held sharpener with multiple abrasive rods to sharpen a cutting edge of a tool
EP2461940B1 (fr) Nouveaux affûteurs pour créer des tranchants à entailles transversales
CA2973976C (fr) Aiguiseur de couteaux epais
US12048979B2 (en) Rotatable edge guide to support a cutting tool during a sharpening operation
US9333612B2 (en) Tool sharpener with adjustable support guide
EP1944128A1 (fr) Taille-crayon abrasif
US20150031274A1 (en) Adjustable knife holder adapted to maintain sharpness of a knife blade and method of manufacturing the adjustable knife holder
US9242331B2 (en) Electric sharpener for ceramic and metal blades
US6997795B2 (en) Versatile manual scissor sharpener
US9545703B1 (en) Miniature knife sharpening apparatus
CN116847950A (zh) 具有精确调节能力的磨刀器
US9623533B2 (en) Sharpening a cutting edge of a tool using a reverse sharpening guide
US10850361B1 (en) Powered sharpener with manual hone stage
WO2013057550A2 (fr) Procédé d'aiguisage et aiguiseur pour une lame à biseau unique
WO2013124705A1 (fr) Procédé d'affûtage et dispositif d'aiguisage de lame
US10675735B2 (en) Handheld sharpening apparatus
US2795975A (en) Rotary knife blade steel
US20220314389A1 (en) Knife Sharpening Device with 1-Point Bearing
US20240238932A1 (en) Knife sharpener
US316731A (en) James beady
KR200334586Y1 (ko) 칼날양면 황토 연마기
Bottorff Sharpening Made Easy: A Primer on Sharpening Knives and Other Edged Tools
Griffin Sharpening a Knife: Information & Tips for a Veterinarian Whose Wife & Meat Cutting Put Him Through College
AU2002301512B2 (en) Knife and blade sharpener

Legal Events

Date Code Title Description
122 Ep: pct application non-entry in european phase

Ref document number: 12784672

Country of ref document: EP

Kind code of ref document: A2