Die-cutting method, flexible abrasive product and apparatus for manufacturing thereof

Abstract

The present invention relates to a method for manufacturing a flexible abrasive product, to such an abrasive product as well as to an apparatus for manufacturing the same. Hereby, the abrasive product is formed to be of the shape of a substantially regular polygon by die cutting it off a material strip. In the present case, the abrasive product has obtained a polygonal shape in which adjacent sides have a reciprocal interior angle of substantially 120 to 150°, whereby the die cutting is carried out in such a way that it coincides at least partly with the die cutting of several adjacent abrasive products. In this way, the die cutting can provide a partially continuous cutting line on the periphery of each individual abrasive product, which cutting line has a significant part of its length in common with the adjacent abrasive products.

1 . A method for manufacturing a flexible abrasive product, which comprises a flexible backing, at least one glue layer on one side of the backing and a layer of abrasive agent bonded thereto by the glue layer, which abrasive product is formed to be of a shape of a substantially regular polygon by die cutting a material strip, characterized by 
 giving the abrasive product a polygonal shape in which adjacent sides have a reciprocal interior angle of substantially 120 to 150° in such a way that    the die cutting is carried out such that it coincides at least partly with the die cutting of several adjacent abrasive products, whereby    a partially continuous cutting line is provided in the die cutting on the periphery of each individual abrasive product, which cuffing line has a significant part of its length in common with adjacent abrasive products.    
   
   
       2 . A method for manufacturing a flexible abrasive product according to  claim 1 , wherein in the manufacture of an octagonal abrasive product a peripheral cutting line is obtained that is common to the extent of  3 / 8 .  
   
   
       3 . A method for manufacturing a flexible abrasive product according to  claim 1 , wherein in the manufacture of a hexagonal or dodecagonal abrasive product a peripheral cutting line is obtained that coincides with six of the sides.  
   
   
       4 . A method for manufacturing a flexible abrasive product according to  claim 1 , wherein the die cutting takes place at two or three stages.  
   
   
       5 . A method for manufacturing a flexible abrasive product according to  claim 4 , wherein the die cutting takes place at work stages following each other successively.  
   
   
       6 . A method for manufacturing a flexible abrasive product according to  claim 5 , wherein the die cutting takes place with two die cutting elements arranged to provide a cutting line on the sides of the polygon in such a way that in the first die cutting stage the common cutting lines are preferably left partially uncut in the transportation direction of the material strip, as is also at least one of the common cutting lines in the cross direction of the material strip, in order to maintain tension and shape in the material strip until the second die cutting, in which the abrasive product is finally detached from the material strip.  
   
   
       7 . A method for manufacturing a flexible abrasive product according to  claim 4  wherein dust extraction openings are formed in the abrasive product at the first die cutting stage.  
   
   
       8 . A method for manufacturing a flexible abrasive product according to  claim 1 , wherein the die cutting takes place with blades such that crossing cutting lines somewhat overlap each other.  
   
   
       9 . A method for manufacturing a flexible abrasive product according to  claim 1 , wherein rows of successive abrasive products are formed in a material strip but are left therein not completely loose from each other, the abrasive products thus forming a continuous chain via connecting parts between them, the abrasive products being subsequently packed.  
   
   
       10 . A method for manufacturing a flexible abrasive product according to  claim 9 , wherein the connecting part between successive abrasion products comprising, in the forming of a continuous chain of abrasive products, a shared tear line weakened by the die cutting in such a way that the abrasive products can be easily detached from each other.  
   
   
       11 . A flexible abrasive product, which comprises a flexible backing, at least one glue layer on one side of the backing and a layer of abrasive agent bonded thereto by the glue layer, which abrasive product is of a shape of a substantially regular polygon and is die cut off a material strip, characterized in that 
 the abrasive product has an even number of sides, whereby    the polygonal shape encompasses abrasive products whose adjacent sides have a reciprocal interior angle of substantially 120 to 150°.    
   
   
       12 . A flexible abrasive product according to  claim 11 , wherein the number of sides is six.  
   
   
       13 . A flexible abrasive product according to  claim 11 , wherein the number of sides is eight.  
   
   
       14 . A flexible abrasive product according to  claim 11 , wherein the number of sides is twelve.  
   
   
       15 . A flexible abrasive product according to  claim 11 , wherein the abrasive product has dust extraction openings.  
   
   
       16 . An apparatus for manufacturing a flexible abrasive product, which abrasive product comprises a flexible backing, at least one glue layer on one side of the backing and a layer of abrasive agent bonded thereto by the glue layer, which abrasive product is arranged to be detached from a material strip with a die cutting tool, characterized in that 
 the structure of the die cutting tool comprises blades arranged to generate substantially rectilinear cutting lines, whereby    the blades are arranged to generate a cutting line which, when completed, is of the shape of a polygon.    
   
   
       17 . An apparatus for manufacturing a flexible abrasive product according to  claim 16 , wherein the blades are divided to at least two successive die cutting elements.  
   
   
       18 . An apparatus for manufacturing a flexible abrasive product according to  claim 16 , wherein the die cuffing tool comprises blades arranged to provide cutting lines which somewhat overlap each other.  
   
   
       19 . An apparatus for manufacturing a flexible abrasive product  claim 16 , wherein the die cutting tool comprises die cutting means for forming dust extraction openings in the abrasive product.