Clamping system for clamping grinding wheels

Abstract

A clamping device for clamping grinding wheels on a driving spindle of a working tool, which includes a rear flange intended to be fitted on the driving spindle in a position proximal to the working tool, wherein the rear flange is provided with a front face with which a first damping element is associated; a front flange intended to be fitted on the driving spindle and provided with a rear face, facing the front face of the rear flange, with which a second damping element is associated; and wherein the front face of the rear flange has a width larger than the rear face of the front flange and the first damping element has a hardness lower than the second damping element.

1 . A clamping device for clamping grinding wheels on a spindle for driving a working tool, which comprises:
 a rear flange intended to be fitted on the driving spindle in a position proximal to the working tool, wherein the rear flange is provided with a front face with which a first damping element is associated;   a front flange intended to be fitted on the driving spindle and provided with a rear face, facing the front face of the rear flange, with which a second damping element is associated;   wherein the front face of the rear flange has a greater width than the rear face of the front flange and the first damping element has a lower hardness than the second damping element.   
     
     
         2 . The clamping device according to  claim 1 , wherein the front face of the rear flange is concave. 
     
     
         3 . The clamping device according to  claim 1 , wherein the front face of the rear flange has an outer diameter greater than 70 mm preferably comprised between 70 mm and 80 mm and the maximum diameter of the front flange is smaller than or equal to 44 mm. 
     
     
         4 . The clamping device according to  claim 1 , wherein the first damping element comprises a layer of a yielding material, preferably elastically, which ex-tends throughout the width of the front face of the rear flange. 
     
     
         5 . The clamping device according to  claim 4 , wherein the thickness of the first damping element is substantially comprised between 2 mm and 4 mm, preferably equal to 3 mm. 
     
     
         6 . The clamping device according to  claim 1 , wherein the first damping element has a hardness higher than or equal to 50 Shore A, preferably between 10 Shore A and 45 Shore A. 
     
     
         7 . The clamping device according to  claim 1 , wherein the second damping element has a hardness higher than 40 Shore A, preferably between 46 Shore A and 90 Shore A. 
     
     
         8 . The clamping device according to  claim 1 , wherein the first damping element is removably associated to the front face of the rear flange, preferably by a snap-fitting. 
     
     
         9 . The clamping device according to  claim 1 , wherein at least one of the front flange and the rear flange comprises a centering shank on which the grinding wheel can be fitted, wherein the distal end of the centering shank has a beveled or rounded or conic annular edge. 
     
     
         10 . The clamping device according to  claim 9 , wherein at least the annular edge is hardened by a surface quenching or concrete-covering process. 
     
     
         11 . The clamping device according to  claim 1 , wherein the rear flange is made of a metal material, preferably selected from the group consisting in steel, aluminium, zamak, bronze or other metal alloys, or is made of a plastic material. 
     
     
         12 . The clamping device according to  claim 1 , wherein at least one of the first damping element and the second damping element has an active surface, adapted to be put in contact with the grinding wheel during use, wherein the active surface has a smooth or structured surface with a structure selected from the group consisting in cylindrical cusp-shaped reliefs, pyramid frustum-shaped reliefs, truncated-cone-shaped reliefs, raised radial ridges and concentrical circumferential ridges. 
     
     
         13 . A working tool comprising:
 a driving unit;   a driving spindle connected to the driving unit: and   a clamping device, according to  claim 1 , for clamping a grinding wheel on the driving spindle.