Method and appartus for retaining a tool in a tool holder with defined contact surfaces

Abstract

A plurality of friction rods each of which is positioned in a hole around the retaining bore with a portion of each of the plurality of friction rods partially protruding into the retaining bore for directly engaging the shank of the tool for holding the shank of the tool in the retaining bore at the defined contact surfaces.

1 - 10 . (canceled) 
     
     
         11 . A method for creating a shrink-fit tool holder for retaining a shank of a tool, the method comprising:
 forming in a front face of a tool holding section centered on a rotational axis a retaining bore for holding the shank of the tool; and   forming in the front face of the tool holding section of the shrink-fit tool holder a plurality of defined contact surfaces each partially protruding in the retaining bore for directly engaging the shank of the tool for holding the shank of the tool in the retaining bore at the defined contact surfaces.   
     
     
         12 . The method for creating the shrink-fit tool holder of  claim 11 , further comprising forming a plurality of circumferentially spaced holes around the retaining bore each for receiving a friction rod of a plurality of friction rods. 
     
     
         13 . The method for creating the shrink-fit tool holder of  claim 12 , further comprising changing a relative diameter of the plurality of circumferentially spaced holes and the friction rods. 
     
     
         14 . The method for creating the shrink-fit tool holder of  claim 13 , further comprising inserting the plurality of friction rods into the corresponding plurality of circumferentially spaced holes. 
     
     
         15 . The method for creating the shrink-fit tool holder of  claim 14 , further comprising fixing the plurality of friction rods in the corresponding plurality of circumferentially spaced holes by allowing a relative diameter of the circumferentially spaced holes and the plurality of friction rods to equalize. 
     
     
         16 . The method for creating the shrink-fit tool holder of  claim 15 , further comprising inserting the shank of the tool into the retaining bore. 
     
     
         17 . The method for creating the shrink-fit tool holder of  claim 16 , wherein the step of inserting the shank of the tool into the retaining bore further comprises changing a relative diameter of the shank of the tool and the retaining bore. 
     
     
         18 . The method for creating the shrink-fit tool holder of  claim 11 , further comprising forming a plurality of depressions around the retaining bore wherein one of the plurality of defined contact surfaces is formed between a pair of plurality of depressions such that the plurality of defined contact surfaces are formed integral with and as a single piece of material with the tool holding section, and wherein the plurality of defined contact surfaces each partially protrude into the retaining bore for directly engaging the shank of the tool for holding the shank of the tool in the retaining bore at the defined contact surfaces. 
     
     
         19 - 20 . (canceled) 
     
     
         21 . The method for creating the shrink-fit tool holder of  claim 11 , wherein the defined contact surfaces are each fixed to and partially protruding into the retaining bore. 
     
     
         22 . The method for creating the shrink-fit tool holder of  claim 11 , wherein the defined contact surfaces each have a hardness greater than or equal to the solid body. 
     
     
         23 . The method for creating the shrink-fit tool holder of  claim 11 , wherein the defined contact surfaces extend from the front face and downward parallel with the retaining bore. 
     
     
         24 . A method for creating a shrink-fit tool holder for retaining a shank of a tool, the method comprising:
 forming in a front face of a tool holding section centered on a rotational axis a retaining bore for holding the shank of the tool; and   forming a plurality of depressions around the retaining bore with defined contact surfaces between pairs of depressions of the plurality of depressions such that the defined contact surfaces are formed integral with and as a single piece of material with the tool holding section, and wherein the defined contact surfaces partially protrudes into the retaining bore for directly engaging the shank of the tool for holding the shank of the tool in the retaining bore at the defined contact surfaces.   
     
     
         25 . The method for creating the shrink-fit tool holder of  claim 24 , wherein the defined contact surfaces are each fixed to and partially protruding into the retaining bore. 
     
     
         26 . The method for creating the shrink-fit tool holder of  claim 24 , wherein the defined contact surfaces each have a hardness greater than or equal to the solid body. 
     
     
         27 . The method for creating the shrink-fit tool holder of  claim 24 , wherein the defined contact surfaces extend from the front face and downward parallel with the retaining bore. 
     
     
         28 . The method for creating the shrink-fit tool holder of  claim 24 , wherein the defined contact surfaces extend from the front face and downward parallel with the retaining bore and each having a hardness equal to the solid body and fixed to and partially protruding into the retaining bore for directly engaging the shank of the tool and for holding the shank of the tool in the retaining bore at the defined contact surfaces.