(19)
(11) EP 2 429 765 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
25.05.2016 Bulletin 2016/21

(21) Application number: 10735484.7

(22) Date of filing: 29.01.2010
(51) International Patent Classification (IPC): 
B24D 13/04(2006.01)
B24D 13/10(2006.01)
(86) International application number:
PCT/DK2010/050026
(87) International publication number:
WO 2010/085964 (05.08.2010 Gazette 2010/31)

(54)

METHOD FOR MANUFACTURING A GRINDING ELEMENT FOR USE IN ROTATING GRINDING OR POLISHING TOOLS AND SUCH GRINDING ELEMENT

VERFAHREN ZUR HERSTELLUNG EINES SCHLEIFELEMENTS FÜR UMLAUFENDE SCHLEIF- ODER POLIERWERKZEUGE UND DERARTIGES SCHLEIFELMENT

PROCÉDÉ DE FABRICATION D'UN ÉLÉMENT DE MEULAGE DESTINÉ À ÊTRE UTILISÉ DANS DES OUTILS ROTATIFS DE MEULAGE OU DE POLISSAGE ET UN TEL ÉLÉMENT DE MEULAGE


(84) Designated Contracting States:
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 SE SI SK SM TR

(30) Priority: 30.01.2009 DK 200900147

(43) Date of publication of application:
21.03.2012 Bulletin 2012/12

(73) Proprietor: Jespersen, Poul Erik
7870 Roslev (DK)

(72) Inventor:
  • Jespersen, Poul Erik
    7870 Roslev (DK)

(74) Representative: Nielsen, Leif et al
Patrade A/S Fredens Torv 3A
8000 Aarhus C
8000 Aarhus C (DK)


(56) References cited: : 
WO-A1-97/35688
DE-B- 1 202 750
US-A- 5 129 191
WO-A1-97/35688
US-A- 2 400 809
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Field of the Invention



    [0001] The present invention relates to a method for manufacturing a grinding element for use in rotating grinding or polishing tools, and which includes abrasive cloth and stiffening brushes, which are mounted and secured in a substantially U-shaped profile with a bottom and two legs, which form side walls, the free edge regions delimiting the opening of the profile, as the profile, the abrasive cloth, the brushes and an adhesive means are continuously advanced to and through a mounting step and a fixing step, where the profile is statically deformed by the free edge regions of the two legs being pressed against each other, in order to narrow the opening and squeeze around and secure the abrasive cloth and the brushes, and by the formed grinding element being cut up into requested lengths.

    Background of the Invention



    [0002] Similar rotating grinding or polishing tools are known, e.g. from document WO 97/35688, which are provided with grinding elements. Such tools are widely used within the woodworking industry and in the metal working industry. The tools can also be used within industry for processing of other materials such a glass fibre constructions.

    [0003] Grinding elements, which were mentioned in the introduction, therefore include a profile, which can have different shapes for placing in a mounting groove in the grinding or polishing tool. Thus the profile can substantially be U-shaped, but generally it will have an undercutting, such as the profile is not flung out of the groove, but instead is secured in the groove. Therefore, the profile will at a free edge region, in which the abrasive cloth and the stiffening brushes extend from the profile, have a smaller distance than the distance at the bottom of the profile.

    [0004] Thus the grinding elements will include the abrasive cloth and stiffening brushes. Such grinding elements have a widely use because of the effective results, which are obtained by grinding of both plane and profiled items. It is important that the abrasive cloth of the grinding elements and brushes of the grinding elements have a correct length in order to have the requested grinding/polishing effect in the finished product.

    [0005] The grinding or polishing tools of such a type in which such grinding elements are used, have preferably been used for grinding and polishing of not-plane surfaces such as curved furniture parts, panelled doors etc. However, this is also extensively used in other areas, in which there can be a machining of plane surfaces.

    [0006] The lamellas of the grinding element are formed by an abrasive cloth is slit transversely of the longitudinal direction, so that tapes or lamellas appear, which are at one end interconnected by means of an unbroken strip of abrasive cloth, which is secured in the U-shaped profile. The free end thus consists of a number of parallel lamellas of abrasive cloth, which extend substantially perpendicular to the longitudinal direction of the profile. In a plane parallel to the grinding lamellas the stiffening brushes will be disposed in immediate vicinity of the lamellas, in that way that they are supporting the lamellas by the grinding.

    [0007] The grinding or the polishing effect is obtained as a result of the effect of the lamellas, as they sweep over an item during rotation of the tool. The stiffening brushes have, like the word says, a function to support the grinding lamellas. The brushes can also be manufactured of a material, so that they contribute to the grinding or polishing effect.

    [0008] The tools can be formed with the grinding elements radially disposed on a grinding or polishing head, or can be axial disposed on the surface of a grinding or polishing cylinder.

    [0009] Thus way the grinding effect can be exerted on a surface, which is perpendicular on the rotation direction of the tool, or on a surface which goes like a tangent to a cylindrical circumference on a cylindrical grinding or polishing tool.

    [0010] The grinding or polishing effect of the tools appears as a result of the effect of the lamellas during their flexible sweeping of the item during the rotation of the tool.

    [0011] In the prior art grinding elements the lamellas and the brushes will be disposed in profiles which can be formed of plastic or metal.

    [0012] To secure the brushes and the lamellas mechanically in the profile, this can squeeze around the elements, and at the same time, the securing can be improved by means of an adhesive, which is disposed in the bottom of the U-shaped profile.

    [0013] In the prior art systems the grinding elements are manufactured in lengths, which correspond with the length on the grinding element which is to be used in a tool.

    [0014] From a manufacturing point of view, it is desired to manufacture grinding elements in endless lengths and cutting them off in the lengths, which are necessary in an actual tool as this will facilitate the production method.

    [0015] This has been a problem because a cutting of the profiles will be combined with drawbacks, as the grinding particles on the abrasive cloth will cause a very large abrasion on the cutting tools.

    Object of the Invention



    [0016] It is an object of the present invention to provide a method for manufacturing a grinding element which is suitable for endless manufacture, which makes it possible to cut up the grinding elements in the required lengths based on an endless manufacture.

    Description of the Invention



    [0017] This is obtained according to the present invention with a method of the introductorily mentioned type which is peculiar by steps including
    conveying a plane metal band;
    applying a longitudinal bead of glue on an area of the metal band which subsequently constitutes a side wall of the profile;
    applying abrasive cloth on the metal band as a first edge region of the abrasive cloth is pressed against the glue bead and as another edge region of the abrasive cloth is stretched beyond a side edge of the metal band;
    folding the metal band for forming the substantially U-shaped profile;
    placing the brushes over the opening in the profile and transversely to the formed profile;
    placing a retainer wire against the opening of the profile;
    inserting the retainer wire in the profile with the brushes disposed between the retainer wire and the side walls and bottom of the profile;
    implementing the fixing step where the free edge regions of the legs are pressed against each other for providing a final shape, such that the legs are provided a converging shape in direction against the free edge regions; and
    implementing the cutting step.

    [0018] With this method it will be possible to manufacture grinding elements in endless lengths.

    [0019] A plane metal band or a metal strip is used in the manufacture. This has a limited thickness which can be 1 mm or less and a width between 3 and 5 cm dependent on the size of the finished U-shaped profile. The metal band is conveyed in a plane state at the same time with applying a bead of glue in the longitudinal direction of the strip. The bead of glue is applied with an extruder nozzle, which is adapted in the instrument, and which makes a glue quantity coordinated with the conveying speed for the metal band. That section of the metal band which is applied a glue joint will after the subsequent folding constitute one of the side walls in the U-shaped profile, as the profile will have side walls which correspond to the branches on the U-shape, and a bottom which corresponds to the bottom of the U.

    [0020] Immediately after applying the glue joint, the abrasive cloth is applied. Just as the metal band, the abrasive cloth will come from reels or another large supply enabling a continuous production process. The abrasive cloth will be an elongated strip of the abrasive cloth, which has a width larger than the height of the final U-shaped profile, such as the grinding lamellas can stretch outside the final U-shaped profile. This means that the abrasive cloth is placed on the metal band with a substantial section of the width, which constitutes the height of the lamellas extending beyond the side edge of the metal band. The first edge region of the abrasive cloth will be pressed against the glue bead. This occurs when the metal band, the glue bead and the abrasive cloth are passed in a nip between two rollers. This may be effected in a very simple way as the abrasive cloth and the metal band are in a plane state.

    [0021] Immediately afterwards the metal band is folded to form the substantially U-shaped profile. The folding can be effected by a rolling of the metal band to the requested profile. At first the side edges of the metal band will be folded up such as they are substantially perpendicular to the non-folded section. In this situation there will still be a large opening which faces upwards in the U-shape.

    [0022] This means that the brushes from the top side can be led down in the upwards facing opening in the profile. This occurs when the brushes are disposed with their longitude extension transversely to the formed longitudinal direction of the profile. The brushes will in this way have a free end stretching beyond the abrasive cloth on the one side and beyond the free edge of the other side of the U-profile. After this a roller wheel can be used to lead the brushes down in the bottom of the U-shaped profile, which still is in an open state. The roller used for forcing down the brushes will at the same time with the circumference have a groove in which a retainer wire is disposed. The retainer wire will be led down in the bottom of the U-profile, at the same time with the brushes being pressed down in the bottom of the profile. The brushes will hereby be disposed with an orientation upwards along each side of the roller wheel, which is used for their downlead. The retainer wire, which is led down, can be made of plastic or metal. In this way the retainer wire is led down into the profile so that the brushes are disposed in a position between the retainer wire and the side walls of the profile respectively the bottom of the profile. On the one side wall the abrasive cloth will be glued on.

    [0023] Then a fixing step is performed in which the U-shaped side walls of the profile are pressed further towards each other, such as a squeezing around the side walls of the profile is established. This squeezing can be effected in the form of rollers, which are led inwards towards the side wall of the profile. During this process the abrasive cloth is kept in a horizontal position. This can be effected as a roller wheel, which keeps the abrasive cloth in a horizontal position, so that it is perpendicular to the grinding brushes, which will have a substantially perpendicular orientation with an extension out of the upwardly facing opening in the profile. As the free edge regions of the legs are pressed against each other, for example by a roller wheel, a final shape is formed in which the legs are provided a converging shape in direction against the free edge regions. The bottom of the U-profile will be wider than the entrance opening at the top of the U-profile, in which the brushes and abrasive cloth are extending.

    [0024] In this situation a subsequent treatment of the grinding strips could be performed, but it will also be possible to perform a cutting of the endless manufactured element in individual grinding elements. As the abrasive cloth is kept in a horizontal orientation, it will be possible to perform a finishing/trimming of the brushes. The trimming can include straightening out fibres and the brushes by using a combing device or similar, which places the brushes parallel with each other. The trimming can also include a shortening of the brushes in height in that way they have a correctly uniform height in proportion to the length of the abrasive cloth. In a such situation, the shortening of the individual grinding elements will first be effected after a trimming is performed.

    [0025] As the legs in the U-shaped profile have a converging shape in direction against the free edge regions of the legs, it will be possible to secure the abrasive cloth and the brushes in the profile. Inside the profile, the glue bead, which is used for gluing on the abrasive cloth on the metal band, and the retainer wire, which is disposed, will fill the interior of the profile, so that both brushes and abrasive cloth are secured not only by the squeezing effect, but also by the gluing to the side wall, and the placing of the retainer wire in the bottom of the U-shaped profile. Because of the converging orientation the retainer wire can not be pulled out from the open side of the profile.

    [0026] According to a further embodiment, the method according to the invention is characterized by a step for removing grain of sand on the mentioned first edge region of the abrasive cloth, before applying the abrasive cloth on the metal band. As the grains of sand are removed on the first edge region, it will be possible to obtain a very well-defined thickness, just as it will be possible to obtain a well-defined thickness on the abrasive cloth and the metal band. Hereby, in a more safe way, a squeezing can be effected which ensures that the elements are secured in the U-shaped profile, as this is squeezed into the final shape with the legs converging in direction against the free edge regions. Besides an edge region without grinding particles/grain of sand will provide a smooth surface, which provides a better glue surface such as the gluing of the abrasive cloth and the metal band is secured best possible.

    [0027] According to a further embodiment, the method according to the invention is characterized in that a trimming step is accomplished before the cutting step. A trimming step will be advantageous in the continuous manufacturing step, rather than a trimming after obtaining individual grinding elements. Hereby the trimming can be proceeding most efficiently.

    [0028] According to a further embodiment, the method according to the invention is characterized in that trimming is chosen among straightening out fibres, which preferably is performed before finishing the fixing step and shortening of the fibres to a predetermined length, which preferably is effected after finishing the fixing step. Trimming will primarily be intended for using in straightening out or alignment of the fibres such as all are orientated parallel to each other. As mentioned, this is performed before finishing the fixing step in which the free edge regions are pressed against each other into the final converging shape. The straightening out of fibres will not only be effected in that section of the fibres, which are situated outside the U-shaped profile, but will also be made for the fibres, which are situated inside the U-profile. As the fibres in the U-profile can move in relation to each other in an intervening closing step, in which the edge regions of the metal band are not brought to the final converging shape, a particular effective straightening out of the fibres is achieved.

    [0029] Trimming can also include a step in which the fibres are shortened to a predetermined length, such as they have a correctly length in relation to the abrasive cloth, which is disposed in the grinding element. A such shortening and trimming of the fibres are particularly efficient, when the abrasive cloth during the trimming is bent away into a horizontal position. Alternatively, the abrasive cloth can be bent away under another angle, as only it is kept away from contact with the fibres of the stiffening brushes.

    [0030] Even if straightening the fibre of the brushes preferably is effected before finishing the fixing step, it could also be effected after finishing the fixing step. The shortening, which will be effected of the fibres, will preferably be performed after finishing the fixing step with the legs in their final converging shape, in which they are statically deformed into the final shape of the substantially U-shaped profile. It is hereby ensured that no changes in the length are performed, and the fibre of the brushes will have a correctly length, when the shortening first is effected, when the fibres are disposed with a final fixing in the profile.

    [0031] According to a further embodiment, the method according to the invention is characterized by slitting the abrasive cloth for the forming of lamellas, as slits extend perpendicularly to the longitudinal direction of the profile from mentioned first edge region of the abrasive cloth to the free edge of the mentioned second edge region of the abrasive cloth. As mentioned the abrasive cloth will preferably be slit, so that lamellas are formed. The lamellas will extend perpendicularly to the longitudinal direction of the grinding elements. The slits are also extending perpendicular to the longitudinal direction of the grinding element. The slits will at least extend from the top side of the profile and perpendicular out from here from the first edge region of the abrasive cloth, which is situated inside and is glued on the profile to the free edge of the other edge region of the abrasive cloth, which extends outside the U-profile.

    [0032] According to a further embodiment, the method according to the invention is characterized in that the slitting of the abrasive cloth is effected by laser cutting. By using laser cutting there is a particular efficient cutting of the abrasive cloth, which contains grinding particles, preferably grain of sand. Hereby, a situation is avoided in which cutting tools are worn down and will only have a short service life.

    [0033] According to a further embodiment, the method according to the invention is characterized in that the cutting up of the grinding element into the requested lengths, is performed by cutting at a slit between two succeeding lamellas, as knives are used for cutting the profile, retainer wire and the mentioned first edge region of the abrasive cloth. After slitting the abrasive cloth by laser cutting traditional knives can be used for the succeeding cutting up of the abrasive cloth in the requested lengths. In that way there will from a slit, which is formed between two succeeding lamellas, be effected a cutting by means of knives, which in a simple way can cut both the retainer wire of the profile and the metal profile. These knives could also cut off the first edge region of the abrasive cloth. When the first edge region of the abrasive cloth is released from grain of sand or other grinding particles, the knives will not be worn unnecessarily. The cutting knives can therefore have a long durability.

    [0034] According to a further embodiment, the method according to the invention is characterized in that the abrasive cloth is secured at a position, where it is kept away from contact with the brushes until the cutting step. As above-mentioned this will be a particular advantage, as trimming and shortening of the brushes hereby are facilitated, compared to a situation in which the abrasive cloth will be disposed in close contact parallel to the fibres of the brushes.

    [0035] According to a further embodiment, the method according to the invention is characterized in that the abrasive cloth at one side edge is slit for forming lamellas, and that the slits extend transversely to the longitudinal direction of the profile. With a such abrasive cloth a particular efficient grinding element is obtained, as the lamellas will make it possible to machine both plane surfaces as profiled surfaces.

    Description of the Drawing



    [0036] The invention will accordingly be explained in further detail with reference to the accompanying schematic drawing, wherein
    Figures 1-9
    show steps in the method according to the invention;
    Figures 10
    shows a partial view of a grinding element obtained through a method according to the invention and;
    Figures 11
    shows a perspective view of a grinding element obtained through a method according to the invention.

    Detailed Description of the Invention



    [0037] The grinding element, which is shown in figures 10 and 11, is generally designated with the reference number 1. The grinding element includes an abrasive cloth 2 and stiffening brushes 3. The abrasive cloth 2 is cut up in a line of lamellas 4 at mutually spaced slits 5. The grinding element includes moreover a substantially U-shaped profile 6. The U-shaped profile 6 squeezes around a section of the abrasive cloth 2 and the brushes 3. Inside the U-shaped profile 6 a retainer wire 7 is provided in a position, such as a section of the grinding brushes are situated between the retainer wire 7 and the bottom 8 of the U-shaped profile 6. The U-shaped profile 6 includes moreover two sides 9, which are converging upwards from the bottom against the free edge regions 10, which enclose an opening 11 through which the abrasive cloth 2 and the brushes 3 are stretched from the profile 6. The opening 11 will have a smaller extension than the bottom 8.

    [0038] The abrasive cloth 2 is glued to the one side wall 9 by means of a glue joint 12 which is shown in figure 10.

    [0039] The production process will now be described with reference to figures 1-9.

    [0040] A strip-shaped metal band 13 is conveyed through a machine on a support. An extruder 14 extrudes a glue joint 15 on an area of the metal band, which subsequently constitutes a side wall 9 of the profile. On figure 2 is seen that an abrasive cloth 2 is applied to the glue joint 15. The abrasive cloth 2 is disposed so that it has an essentially extension 16, which goes beyond the side edge 10 of the metal band 13. The inner side edge 17 of the abrasive cloth 2 will be located in a position, which approximately corresponds to the bottom section of a side wall 9 by the transition to bottom 8.

    [0041] By means of a pressing means 18, which for example could be a roller or similar the abrasive cloth 2 is pressed down against the metal band 13, which rests on a support. Hereby the extruding bead of glue 15 will be pressed out and form a glue joint between the abrasive cloth 2 and the metal band 13. Before applying the glue joint, the abrasive cloth is released from grain of sand in a edge region 19, which is intended for contact with the metal band.

    [0042] On figure 3 is seen a succeeding step, in which the metal band obtains a beginning rolling in order to bend the side walls 9 upwards. This is effected by using rollers 20, which are pressing against the side walls of the metal band 13. The metal band can during this rolling be kept with the bottom 8 in contact with the support by means of a counter-pressure roller (not shown). During this process the abrasive cloth 2 is kept in a horizontal position such as illustrated in figure 3. Hereafter a slitting of the free section 21 of the abrasive cloth is performed, which extends outside the profile 6. The slitting is performed by means of a laser 22, which forms the slitting 5 in order to form the lamellas 4.

    [0043] As it appears from figure 4, the side walls 9 are rolled further upwards such as they are disposed substantially perpendicular compared to the bottom 8. The abrasive cloth 2, which now is slit, is still kept in a horizontal position.

    [0044] Then the brushes 3 are provided or rather the fibres, which form the brushes with an orientation transversely of the longitudinal direction of the profile 6. A central region 23 of each single fibre in the brushes 3 is in that way disposed out from the upwards turning opening 11 in the profile. A roller 24 with a groove 25 for accommodating the retainer wire 7 being disposed out from the opening 11. The roller 24 is rotated around the axis 26 with a direction of the rotation 27, such as this is effected synchronously with the conveying of the metal strip and the attached abrasive cloth during the production process.

    [0045] On figure 6 is shown a further step in which the roller 24 is pressed into the still open profile, such that the retainer wire 7 is pressing the fibres down towards the bottom 8 of the profile 6. In this position the abrasive cloth is still kept in a horizontal position. The brushes 3 are now substantially vertically with a parallel orientation on each side of the roller 24.

    [0046] Then the roller is withdrawn, and as it appears from figure 7, another roller 28 will press against the side walls 9, such as these assume an inwards converging shape, in which the free edge regions 10 are led to a position closer to each other and thereby squeezing the brushes 3 and the abrasive cloth 2.

    [0047] In the formed profile the retainer wire 7 will be provided inside the bent edges and have a such diameter that it cannot be pulled out of the opening 11, as it is squeezed around the brushes 3 and the abrasive cloth 2. Afterwards a trimming is performed as illustrated in figure 8. The trimming is effected by the brushes 3 being machined with a trimming adaptation, which here is indicated in the shape of a vane wheel 29, which is rotated around an axis 30 substantially parallel with the longitudinal direction for the profile 6 in direction 31.

    [0048] The individual vanes 32 will afterwards be coated through the fibre strand, which constitutes the brush 3. The fibres are hereby disposed in a parallel orientation, in which they are created with a position substantially perpendicular on the longitudinal direction of the profile 6. In this position the free edge regions 10 are not yet brought to the final squeezed position. This is firstly effected in the further step which is illustrated in figure 9.

    [0049] Here will further rolls or clamping jaws 33 press the profile into the final shape with the final converging, in which there is a firm engagement, which secures the fibres in the brush 3 and the abrasive cloth 2. The retainer wire 7 is disposed in the bottom of the profile 6. In this way the compression, which is mentioned above in connection with figure 8, will solely ensure that the retainer wire 7 is not stretched out, and that the brushes 3 are not stretched out of the profile 6, but still allows that the fibres of the brushes can be arranged not only outside the profile, but also in the opening 11 of the profile.

    [0050] After the final compression with the rollers or the jaws 33 the final fixing will be performed. Then a shortening in height of the brushes 3 is performed. This is effected by using a cutting means 34, which includes a rotating blade 35, which interacts with a retaining blade 36, which defines the height of the fibres. In figure 9 an enlarged picture is illustrated of an alternative shape, which shows hammers 38 with rotating knives 37, and which also acts against the retaining blade 36 for shortening of the brushes 3. The hammers 38 are rotated in direction of the arrow 39.


    Claims

    1. Method for manufacturing a grinding element (1) for use in rotating grinding or polishing tools, and which includes abrasive cloth (2) and stiffening brushes (3), which are mounted and secured in a substantially U-shaped profile (6) with a bottom (8) and two legs, which form side wall (9), the free edge regions delimiting the opening of the profile, as the profile, the abrasive cloth (2), the brushe (3) and an adhesive means are continuously advanced to and through a mounting step and a fixing step, where the profile is statically deformed by the free edge regions of the two legs being pressed against each other in order to narrow the opening and squeeze around and secure the abrasive cloth and the brushes, and by the formed grinding element being cut up into requested lengths, characterized by the following steps:

    conveying a plane metal band (13);

    applying a longitudinal bead of glue (15) on an area of the metal band which subsequently constitutes a side wall of the profile;

    applying abrasive cloth (2) on the metal band (13) as a first edge region of the abrasive cloth is pressed against the glue bead (15) and as another edge region of the abrasive cloth is stretched beyond a side edge of the metal band;

    folding the metal band (13) for forming the substantially U-shaped profile (6);

    placing the brushes over the opening (11) in the profile and transversely to the formed profile;

    placing a retainer wire (7) against the opening of the profile;

    inserting the retainer wire in the profile with the brushes disposed between the retainer wire and the side walls and bottom (8) the profile;

    implementing the fixing step where the free edge regions of the legs are pressed against each other for providing a final shape, such that the legs are provided a converging shape in direction against the free edge regions; and

    implementing the cutting step.


     
    2. Method according to claim 1, characterized by a step for removing grain of sand on the mentioned first edge region of the abrasive cloth, before applying the abrasive cloth on the metal band.
     
    3. Method according to claim 1 or 2, characterized in that a trimming step is accomplished before the cutting step.
     
    4. Method according to claim 3, characterized in that trimming is chosen among straightening out fibres, which preferably is performed before finishing the fixing step and shortening of the fibres to a predetermined length, which preferably is effected after finishing the fixing step.
     
    5. Method according to any of the claims 2 - 4, characterized by slitting the abrasive cloth for the forming of lamellas, as slits extend perpendicularly to the longitudinal direction of the profile from mentioned first edge region of the abrasive cloth to the free edge of the mentioned second edge region of the abrasive cloth.
     
    6. Method according to claim 5, characterized in that the slitting of the abrasive cloth is effected by laser cutting.
     
    7. Method according to claim 5 or 6, characterized in that the cutting up of the grinding element into the requested lengths, is performed by cutting at a slit between two succeeding lamellas, as knives are used for cutting the profile, retainer wire and the mentioned first edge region of the abrasive cloth.
     
    8. Method according to any of the previous claims, characterized in that the abrasive cloth is secured at a position, where it is kept away from contact with the brushes until the cutting step.
     


    Ansprüche

    1. Verfahren zum Fertigen eines Schleifelement (1) zur Verwendung in umlaufenden Schleif- oder Polierwerkzeugen, und das Schleifgewebe (2) und Versteifungsborsten (3) einschließt, die in einem im Wesentlichen U-förmigen Profil (6) mit einer Unterseite (8) und zwei Schenkeln, die die Seitenwände (9) bilden, montiert und befestigt sind, wobei die freien Randregionen die Öffnung des Profils begrenzen, wenn das Profil, das Schleifgewebe (2), die Borsten (3) und ein Klebemittel kontinuierlich zu einem Montageschritt und einem Fixierschritt vorgeschoben und durch diese hindurch geführt werden, wo das Profil statisch verformt wird, indem die freien Randregionen der beiden Schenkel gegeneinander gepresst werden, um die Öffnung zu verengen und um das Schleifgewebe und die Borsten herum zu quetschen und zu befestigen, und wobei das gebildete Schleifelement in erforderliche Längen aufgeschnitten wird, gekennzeichnet durch die folgenden Schritte:

    Transportieren eines ebenen Metallbands (13);

    Aufbringen einer längsgerichteten Klebstoffperle (15) auf einen Bereich des Metallbands, der anschließend eine Seitenwand des Profils darstellt;

    Aufbringen von Schleifgewebe (2) auf das Metallband (13), wenn eine erste Randregion des Schleifgewebes gegen die Klebstoffperle (15) gepresst wird und wenn eine andere Randregion des Schleifgewebes über einen Seitenrand des Metallbands hinaus gedehnt wird;

    Falten des Metallbands (13), um das im Wesentlichen U-förmige Profil (6) zu bilden;

    Platzieren der Borsten über der Öffnung (11) in dem Profil und quer zu dem gebildeten Profil;

    Platzieren eines Haltedrahts (7) an der Öffnung des Profils;

    Einführen des Haltedrahts in das Profil, wobei die Borsten zwischen dem Haltedraht und den Seitenwänden und der Unterseite (8) des Profils angeordnet sind;

    Implementieren des Fixierschritts, wo die freien Randregionen der Schenkel gegeneinander gepresst werden, um eine endgültige Form bereitzustellen, sodass die Schenkel in einer konvergierenden Form in Richtung auf die freien Randregionen bereitgestellt werden; und

    Implementieren des Schneidschritts.


     
    2. Verfahren nach Anspruch 1, gekennzeichnet durch einen Schritt zum Entfernen von Sandkörnern auf der genannten ersten Randregion des Schleifgewebes, bevor das Schleifgewebe auf das Metallband aufgebracht wird.
     
    3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass ein Trimmschritt vor dem Schneidschritt ausgeführt wird.
     
    4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, dass das Trimmen ausgewählt ist aus Glätten der Fasern, das vorzugsweise vor Abschluss des Fixierschritts durchgeführt wird, und Kürzen der Fasern auf eine festgelegte Länge, das vorzugsweise nach Abschluss des Fixierschritts durchgeführt wird.
     
    5. Verfahren nach einem der Ansprüche 2 - 4, gekennzeichnet durch das Aufschlitzen des Schleifgewebes zur Bildung von Lamellen, da sich die Schlitze senkrecht zu der Längsrichtung des Profils von der genannten ersten Randregion des Schleifgewebes bis zu dem freien Rand der genannten zweiten Randregion des Schleifgewebes erstrecken.
     
    6. Verfahren nach Anspruch 5, dadurch gekennzeichnet, dass das Aufschlitzen des Schleifgewebes durch Laserschneiden bewirkt wird.
     
    7. Verfahren nach Anspruch 5 oder 6, dadurch gekennzeichnet, dass das Aufschneiden des Schleifelements in die erforderlichen Längen durchgeführt wird, indem an einem Schlitz zwischen zwei aufeinanderfolgenden Lamellen geschnitten wird, da Klingen zum Schneiden des Profils, Haltedrahts und der genannten ersten Randregion des Schleifgewebes verwendet werden.
     
    8. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass das Schleifgewebe in einer Position befestigt wird, in der es bis zum Schneidschritt von einem Kontakt mit den Borsten ferngehalten wird.
     


    Revendications

    1. Procédé de fabrication d'un élément de meulage (1) destiné à être utilisé dans des outils rotatifs de meulage ou de polissage, et qui comprend un tissu abrasif (2) et des brosses de rigidification (3), qui sont montés et fixés dans un profil substantiellement en forme de U (6) avec un fond (8) et deux branches, qui forment des parois latérales (9), les régions de bord libres délimitant l'ouverture du profil, tel que le profil, le tissu abrasif (2), les brosses (3) et un moyen adhésif sont avancés en continu vers et à travers une étape de montage et une étape de fixation, où le profil est déformé de façon statique par les régions de bord libres des deux branches pressées l'une contre l'autre afin de réduire l'ouverture et de presser le pourtour et de fixer le tissu abrasif et les brosses, et par l'élément de meulage formé coupé dans des longueurs requises,
    caractérisé par les étapes suivantes :

    transport d'une bande métallique plane (13) ;

    application d'un cordon de colle longitudinal (15) sur une zone de la bande métallique qui constitue ensuite une paroi latérale du profil ;

    application d'un tissu abrasif (2) sur la bande métallique (13) tel qu'une première région de bord du tissu abrasif est pressée contre le cordon de colle (15) et tel qu'une autre région de bord du tissu abrasif est étirée au-delà d'un bord latéral de la bande métallique ;

    pliage de la bande métallique (13) pour former le profil substantiellement en forme de U (6) ;

    placement des brosses au-dessus de l'ouverture (11) dans le profil et transversalement au profil formé ;

    placement d'un fil de retenue (7) contre l'ouverture du profil ;

    insertion du fil de retenue dans le profil avec les brosses disposées entre le fil de retenue et les parois latérales et le fond (8) du profil ;

    mise en oeuvre de l'étape de fixation où les régions de bord libres des branches sont pressées l'une contre l'autre pour fournir une forme finale de telle sorte que les branches sont dotées d'une forme convergente dans une direction opposée aux régions de bord libres ; et

    mise en oeuvre de l'étape de coupe.


     
    2. Procédé selon la revendication 1, caractérisé par une étape de retrait de grain de sable sur la première région de bord mentionnée du tissu abrasif, avant application du tissu abrasif sur la bande métallique.
     
    3. Procédé selon la revendication 1 ou 2, caractérisé en ce qu'une étape de rectification est réalisée avant l'étape de coupe.
     
    4. Procédé selon la revendication 3, caractérisé en ce que la rectification est choisie parmi le redressage de fibres, qui est réalisé de préférence avant la fin de l'étape de fixation et le raccourcissement des fibres à une longueur prédéterminée, qui est effectué de préférence après la fin de l'étape de fixation.
     
    5. Procédé selon l'une quelconque des revendications 2 - 4, caractérisé par le fendage du tissu abrasif pour la formation de lamelles, tel que des fentes s'étendent perpendiculairement à la direction longitudinale du profil de la première région de bord mentionnée du tissu abrasif au bord libre de la deuxième région de bord mentionnée du tissu abrasif.
     
    6. Procédé selon la revendication 5, caractérisé en ce que le fendage du tissu abrasif est effectué par coupe laser.
     
    7. Procédé selon la revendication 5 ou 6, caractérisé en ce que la coupe de l'élément de meulage dans les longueurs requises est réalisée par coupe au niveau d'une fente entre deux lamelles successives, tel que des couteaux sont utilisés pour couper le profil, le fil de retenue et la première région de bord mentionnée du tissu abrasif.
     
    8. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que le tissu abrasif est fixé à une position, où il est maintenu hors de contact des brosses jusqu'à l'étape de coupe.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description