Apparatus for removing an abrasive element in a machine for working surfaces and related removal method

Abstract

An apparatus for removing an abrasive element having a perimeter edge delimiting an abrasive surface in a machine for finishing surfaces comprising a support body for removably engaging the abrasive element. The support body and the abrasive element are, respectively, provided, at respective engagement surfaces of first and second engagement members configured to move, from an engagement configuration to a disengagement configuration, and vice versa. A displacement device is, furthermore, provided to move the support body in the space according to at least 1 degree of freedom. A removal group is, furthermore, provided comprising at least a removal member adapted to rotate about a rotation axis and provided with a removal surface. This is adapted to engage the second engagement members to cause the first and second engagement members to move from the engagement configuration to the disengagement configuration.

1 . A machine for finishing surfaces comprising:
 a support body configured to removably engage an abrasive element having a perimeter edge delimiting an abrasive surface, said support body and said abrasive element being, respectively, provided, at respective engagement surfaces of first and second engagement members configured to move, from an engagement configuration to a disengagement configuration, and vice versa;   a displacement device configured to move said support body in the space according to at least 1 degree of freedom;   an apparatus for removing said abrasive element from said support body;
 said machine being characterized in that said apparatus comprises a removal group provided with at least a removal member configured to rotate about a rotation axis in a predetermined direction of rotation, said or each removal member being provided with a removal surface configured to cause said first and second engagement members to move from said engagement configuration to said disengagement configuration; 
 in that said displacement device is configured to position said abrasive surface of said abrasive element in contact with said removal surface at a predetermined removal zone with a predetermined starting inclination (αi) with respect to said rotation axis, and in that said predetermined starting inclination (αi) is such that said removal member is adapted to cause said first and second engagement members to move from the engagement configuration to the disengagement configuration starting from a perimeter portion adjacent to said perimeter edge. 
   
     
     
         2 . Machine according to  claim 1 , wherein a barrier member is, furthermore, positioned downstream of said removal zone with respect to said direction of rotation of said or each removal member, said barrier member being configured to be positioned between said abrasive element and said or each removal member during the removal of said abrasive element from said support body. 
     
     
         3 . Machine according to  claim 1 , wherein said removal surface is configured to engage said second engagement members of said engagement surface of said abrasive element. 
     
     
         4 . Machine according to  claim 1 , wherein said removal group comprises:
 a first removal member adapted to rotate about said rotation axis;   at least a second removal member adapted to rotate about said rotation axis and positioned at a predetermined distance from said first removal member.   
     
     
         5 . Machine according to  claim 4 , wherein said first and said at least a second removal member belong to the same cylindrical body and are separated by a groove having a width equal to said predetermined distance and coaxial to said rotation axis. 
     
     
         6 . Machine according to  claim 1 , wherein said displacement device, during said removal action of said removal group, is configured to move said support body along an advancing direction from said predetermined starting inclination (αi) to a predetermined final inclination (αf) less than said predetermined starting inclination (αi) and substantially parallel to said rotation axis, said direction of rotation of said or each removal member being opposite to said advancing direction of said support body. 
     
     
         7 . Machine according to  claim 1 , wherein said predetermined starting inclination (αi) is comprised between 15° and 75°. 
     
     
         8 . Machine according to  claim 1 , wherein said removal group comprises, furthermore, a stretching member configured to stretch said abrasive element, during the removal of said abrasive element by the or each removal member in such a way to avoid that said abrasive element can form folds or wrinkles during the action of the or each removal member. 
     
     
         9 . Machine according to  claim 8 , wherein said stretching member is configured to rotate about a rotation axis in a predetermined direction of rotation opposite to said direction of rotation, said rotation axis being parallel to said rotation axis of said or each removal member. 
     
     
         10 . Machine according to  claim 1 , wherein a reference surface is, furthermore, provided having a known spatial position, said displacement device, before positioning said abrasive element at said or each removal member being configured to position said abrasive surface of said abrasive element adjacent to said reference surface and assuming said known spatial position of said reference surface as the spatial position of said abrasive surface. 
     
     
         11 . Machine according to  claim 10 , wherein said reference surface is positioned at least at a support member of a rotation shaft on which said or each removal member is mounted. 
     
     
         12 . Machine according to  claim 1 , wherein said removal surface of said removal member is substantially flat. 
     
     
         13 . Machine according to  claim 1 , wherein said removal member is a disc configured to rotate about said rotation axis. 
     
     
         14 . Machine according to  claim 13  wherein said rotation axis is adapted to pass through the centre of said disc. 
     
     
         15 . Machine according to  claim 1 , wherein said removal member is provided with at least a groove coaxially arranged to said rotation axis. 
     
     
         16 . Machine according to  claim 1 , wherein said removal member is provided with a plurality of grooves coaxial to said rotation axis. 
     
     
         17 . Machine according to  claim 1 , wherein a collecting container is, furthermore, provided having an inlet mouth positioned below the removal group through which said abrasive members fall once removed from said support body. 
     
     
         18 . Machine according to  claim 17 , wherein said inlet mouth of said collecting container is positioned at a top wall of said container body. 
     
     
         19 . Machine according to  claim 17 , wherein said inlet mouth of said collecting container is positioned at a lateral wall of said container body. 
     
     
         20 . Machine according to  claim 17 , wherein said collecting container is provided with at least a guide wall configured to guide said removed abrasive element towards said inlet mouth. 
     
     
         21 . Machine according to  claim 2 , wherein said barrier member comprises at least a protruding portion adapted to be positioned between said first and said at least a second removal member. 
     
     
         22 . Machine according to  claim 2 , wherein said barrier member comprises a main portion from which a plurality of protruding portions is adapted to protrude, each of which configured to be positioned, in use, between said first and said at least a second removal member. 
     
     
         23 . Machine according to  claim 22 , wherein said main portion of said barrier member is inclined at a predetermined angle with respect to said rotation axis. 
     
     
         24 . A method for removing an abrasive element having a perimeter edge delimiting an abrasive surface in a machine for finishing surfaces, said method comprising the steps of:
 providing a support body configured to removably engage said abrasive element, said support body and said abrasive element being, respectively, provided, at respective engagement surfaces of the first and second engagement members configured to move from an engagement configuration to a disengagement configuration, and vice versa;   moving said support body in the space according to at least 1 degree of freedom by a displacement device;
 said method being characterized in that a removal step is, furthermore, provided for removing said abrasive element from said support body, said removal step comprising the steps of: 
   rotating at least a removal member about a rotation axis in a predetermined direction of rotation, said or each removal member being provided with a removal surface configured to engage said second engagement members of said engagement surface of said abrasive element at a removal zone to cause said first and second engagement members to move from said engagement configuration to said disengagement configuration;   positioning by said displacement device said abrasive surface of said abrasive element in contact with said or each removal member at a predetermined removal zone with a predetermined starting inclination (αi) with respect to said rotation axis, said predetermined starting inclination (αi) being such that said removal member is adapted to cause the first and second engagement members to move from the engagement configuration to the disengagement configuration starting from said perimeter edge.