Packaging unit composed of flat abrasive elements and method of packaging flat abrasive elements

0001The invention relates to a packaging unit of sheet Abrasives and a method for packaging flat Abrasive according to the preamble of the independent claims and the use of hot melt adhesive or a dispersion adhesive in a packaging unit for flat abrasive.

0002For grinding and polishing are flat abrasive in a plurality of known different embodiments. Depending on the application, the abrasive, for example, offered as tapes, discs or rectangular sheets. Slices and leaves are often stacked and Abrasive belts packed as rolled coils. The stack or the spirals through the packaging or Packing aids, eg bands held together. After initial removal of packing or packaging aids The individual layers of the abrasive no longer held together. The packaging in solid and Although resealable boxes has this disadvantage does not occur, but leads to an increased consumption of packaging material and undesirably large amounts of waste.

0003It is therefore an object of the present invention, the to avoid the disadvantages of the known, ie, in particular a Packaging unit of a plurality of layers of a sheet-like to provide abrasive, which from the use reduced packaging material and in which the individual Layers of the abrasive also after the first removal of a Abrasive are reliably held together. The Package is also with little technical Effort produced in a simple and economical manner be. is a further object of the present invention to provide a process for the preparation of the novel Package.

0004According to the invention these objects are achieved by a packaging unit or by a method with the features of the characterizing Part of the independent patent claims.

0005The grinding means are in a packaging unit as a Plurality of adjacent layers packaged. The documents can both by individual, flat grinding wheels or also by layers of a spirally wound abrasive belt are formed. The abrasives have all at least a grinding surface and a, the grinding surface bounding Edge. According to the invention, the individual layers in at least one edge portion releasably interconnected. In the case of superimposed in a stack of grinding wheels or sanding sheets can if necessary an abrasive be separated from the stack. In the case of spiral wound abrasive belts, the desired length of the spiral will be replaced.

0006Basically, different possibilities for releasably Bonding the individual layers is conceivable. The edge regions the layers may, for example sewn together or are held together by brackets. However, it has been found that the use of an adhesive, in particular a hot melt adhesive or a dispersion adhesive is particularly advantageous. The edges of the individual Principles of abrasives with the adhesive wholly or are partially covered. Depending on the shape and thickness of the Abrasives are different arrangements of adhesive advantageously on the edges.

0007Alternatively, it is also conceivable for an adhesive on a to use support material. stabilizes the carrier material the adhesive layer. This can in particular during the Applying the layer can be advantageous.

0008In a first advantageous embodiment, stacked flat grinding wheels or abrasive discs and in the edge regions joined together.

0009The approximately rectangular sanding sheets are at least one side interconnected. It is particularly advantageous but that sanding sheets on two sides together to connect. For consideration is the placement of the adhesive layer on mutually opposite sides as well as on two angularly stationary and touching Pages. The connection of more than one side leads to a better stability of the stack of abrasive and therefore particularly when grinding leaves with coarse grain, which are relatively heavy, advantageous.

0010When stacked, circular grinding wheels is the Adhesive layer advantageously over several, advantageously about three peripheral angle ranges of the disks coated. It has turned out that several, over peripheral angle ranges of less than 10 ° extending adhesive layers are particularly advantageous and to the necessary stability to lead.

0011In another embodiment of the invention, a spiral wound abrasive belt together. The Edges of the sanding belt form two sides of a Spiral. The individual layers of the abrasive belt are Adhesive held together on the side faces of the spiral. Particularly advantageous is the application of adhesive found only in part sections of the side surfaces of the spiral. The adhesive may, for example, in one or extending a plurality of approximately through the center of the spiral Strips are applied. Alternatively, it is also conceivable the adhesive only in certain angular ranges of Side surfaces apply.

0012The larger the required stability of the packaging unit is, the larger the area covered by adhesive surface selected. In special cases (or even to simplify the application process), the entire side surface of the spiral or both side faces are covered with adhesive.

0013In the process for packaging the flat abrasive in these in a first process step, several layers superimposed. This can be both by the formation of a Stack of sheet-like grinding wheels or abrasive discs as well as by rolling of abrasive belts in a spiral happen. In a subsequent process step, the different layers of the abrasive in at least one Edge portion releasably interconnected. particularly easy can realize the inventive method when to be joined edge portions, a layer of applied hot melt adhesive or a dispersion adhesive becomes. The edge portions can also by applying other adhesives or by means of clamps, sewn threads or like are held together.

0014According to the invention an adhesive, in particular a Melt adhesive or a dispersion adhesive for releasably Connecting edge portions of a plurality of superimposed Layers of a sheet-like abrasive in a Package used. The use of adhesives for holding together of pages of books or notepads is known. The advantages of such previously described Adhesives for packaging abrasive but has been not Recognised. For additional reinforcement of the packaging unit, in particular during transport, the packaging unit additionally comprises with stamps. to Labeling of the packaging unit, it is conceivable that top layer of abrasive by a caption to replace, for example, by a printed rectangle or a printed disc.

0015The invention will in the following exemplary embodiments and explained in more detail with reference to the drawings. Show it:<dl tsize="18"><dt>figure 1</dt><dd>a perspective view of an inventive Package of sanding sheets,</dd><dt>2a to 2c</dt><dd>Various embodiments of the packaging unit of Figure 1 in top view,</dd><dt>figure 3</dt><dd>a schematic representation of the removal of a according sanding sheet of a packaging unit Figure 1,</dd><dt>figure 4</dt><dd>a perspective view of an inventive Package of grinding wheels,</dd><dt>5a to 5c</dt><dd>various embodiments of a packaging unit from grinding wheels, in plan view</dd><dt>6a</dt><dd>a perspective view of an inventive Package spirally from a wound abrasive belt,</dd><dt>figure 6b</dt><dd>a perspective view of an alternative Embodiment according to FIG 6a,</dd><dt>figure 7</dt><dd>a cross-section along line AA through the Package according to FIG 6a, </dd><dt>figure 8</dt><dd>an inventive arrangement with alternative Connecting means, and</dd><dt>figure 9</dt><dd>an embodiment with a on a support material applied adhesive layer.</dd></dl>

00161 shows schematically in a perspective view an inventive arrangement 1 of a variety in several layers 10 superposed rectangular sanding sheets 2. The sanding sheets 2 have an abrasive surface 7 and are bounded by an edge. 8 The different 10 layers of the abrasive 2 are on the edge 8 on the one Page 3 by a coating layer 20 of an adhesive held together. The adhesive is a beneficial Melt adhesive or dispersion adhesive, for example, Synthetic resin dispersion based on polyvinyl acetate as PLANATOL BB Superior PLANATOL Klebetechnik GmbH, used. The adhesive can be applied directly as a layer. It but it is also conceivable, adhesive on a carrier material to use (see Figure 9).

0017There are many different options are possible, including individual plies 10 can be held together. 2a 2c show three such possibilities.

0018Figure 2a shows the embodiment according to Figure 1 in the Top view. The adhesive layer 20 is on one side 3a applied to the edges 8 of the sanding sheets. 2

0019Figure 2b shows an inventive arrangement in plan view, according to which the individual layers of the abrasive sheets 2 on two opposite sides 3a, 3b through an adhesive layer 20 held together. An assembly according to Figure 2b is especially in coarse and heavy Abrasives advantageous.

0020Figure 2c shows a further advantageous embodiment. The Abrasive sheets 2 are also at two sides 3a, 3c at the edge 8 is connected by an adhesive layer 20 to each other. The Sides 3a, 3c according to 2c are but angularly and touching. With such an arrangement is a similarly good stability achieved as shown in Figure 2b. The but removal of the sanding sheets 2 designed due the exposed corner 4 easier.

0021Figure 3 shows schematically how a sanding sheet 2 for use can be removed. Thanks to the detachable connection of the individual 10 layers of sanding sheets 2 with one another, a Sanding sheet 2 is raised and the rest of the packaging unit 1 demolished.

0022Of course, in certain cases, the adhesive layer 20 only on certain portions of the sides 3a and 3b are applied. This adhesive can be saved will.

0023Figure 4 shows a perspective view of an inventive Arrangement 1, in which circular grinding wheels 22 are superimposed in several layers 10th The abrasive wheels 22 are applied by, in a peripheral portion 23a Adhesive layer interconnected. Depending on the type of the superposed grinding wheels 22, the adhesive layer 20 over larger peripheral angle ranges α or also be applied in a plurality of circumferential portions.

0024Figure 5a shows a top view of the arrangement 1 according to FIG 4. The grinding wheels 22 are in a peripheral portion 23a, which extends over an angular range α by Adhesive layer 20 joined together.

0025If a more stable connection of the individual layers 10 of Grinding wheels 22 is desired, the individual layers 10 5b schematically in figure in a larger Peripheral portion 23 are joined together. The circumferential angle α, in which the adhesive layer 20 on the edge 8 of the grinding wheels is applied, is more than 90 °. The larger of these selected circumferential angle α is, the better the stability of the arrangement is 1. When increasing peripheral angle ranges assumes consumption Adhesive to and the removal of individual gaskets 22 difficult. Depending on the size and thickness of the individual Grinding wheels is the ideal size of the peripheral angular range α found.

00265c shows a particularly preferred embodiment, according to which the individual plies 10 of the grinding wheels 22 through on its edge 8 in two circumferential portions 23a, 23b an applied adhesive layer 20 are held together. The two adhesive layers can be over relatively small circumferential angular ranges α1, α2 extend. The required stability is determined by the two, one another oppositely disposed layers 20 ensured. Of course it is also conceivable, more than 2, for example 3 or 4 peripheral portions with an adhesive layer 20 to provided. This leads to a particularly good stability.

0027Figures 6a and 6b show two embodiments of a inventive arrangement with a grinding belt 12. The Grinding belt 12 is rolled up into a spiral eleventh The spiral 11 has multiple layers 10 of the grinding belt 12, which are connected together at the edge 13a of the abrasive belt 12th To connect the individual layers 10, a layer 20 of an adhesive on the plane formed by the grinding belt 12 Side surface 16 of the spiral 11 is applied. The adhesive layer 20 holds the individual layers of the sanding belt 12 releasably together, but allows unwinding a portion of the sanding belt 12 from the spiral 11. In the embodiment according to FIG 6a, the adhesive layer 20 in a Strip 15 is applied, the extending through the center 18 Spiral extends. Advantageously, the location of the adhesive layer 20 on the side surface 16 of the scroll 11 so chosen, that the beginning 19 of the sanding belt of the adhesive layer is held twentieth The choice of over small circumferential angle extending strip leads with low adhesive consumption to increased stability.

00286b shows an alternative embodiment, according to wherein the adhesive layer 20 is applied in a section 17 is that over a certain angle at circumference β extends. The angle range β function the required stability elected. It is also conceivable that whole side surface 16 or both sides with a Adhesive layer to provide 20th

0029In Figure 7 is a cross section according to the arrangement Figure 6a shown. The adhesive layer 20 is on a Side surface 16 of the spiral 11 is applied. The edges 13a, 13b of the grinding belt 12 are on one side by the adhesive layer 20 together.

0030Figure 8 shows an alternative embodiment of a inventive packaging unit 1. The various 10 layers of an abrasive sheet 2 are on an edge 8 with means other than held together with an adhesive layer. Figure 8 shows schematically a suture 30, which the individual layers 10 together. The sanding sheets 2 are provided with perforations 31 along which they be torn are. Naturally, it is conceivable, instead the seam 30 staples or similar connecting means to use.

0031Figure 9 schematically shows a cross section through several Lay of adjacent layers 10 of an abrasive. In this embodiment, the layers 10 by a Adhesive layer held together, which on a carrier strip is plotted 21st contained on a carrier material Adhesive has especially in the production of the packaging unit Advantages. The carrier tape can be connected to the Up portions are inserted and the adhesive can then, for example, by applying heat to the Portions are applied. The carrier tape 21 is advantageous tearable formed.