Tool holder for drilling and chiselling tools

Tool holder for drilling and chiselling tools comprising an axially extending receiving sleeve having a first end and a second end spaced apart in the axial direction and a bore formed by said sleeve and extending in the axial direction therethrough, said bore having a first axially extending bore section extending from the first end toward the second end, and a second axially extending bore section extending from said second end toward said first end, said first bore section arranged to receive a shank of a drilling or chiselling tool and said second bore section arranged to receive a drive spindle of a drive device, spring biased locking elements located in said receiving sleeve within said first bore section, said first bore section has inwardly projecting axially extending shoulders therein arranged to interfit with correspondingly shaped grooves on the shank of a drilling or chiselling tool, said locking elements are arranged to fit into recesses in the shank of a drilling or chiselling tool, wherein the improvement comprises that said first bore section has an axially extending conically shaped inner surface with the diameter thereof reducing from the first end toward the second end of said receiving sleeve and a radially outer surface, said shoulders project in the axial direction radially inwardly from said conically shaped inner surface and are spaced equiangularly apart around said conically shaped surface, and said locking elements are axially elongated pins extending transversely of the axial direction of said receiving sleeve and extending generally tangentially of said first bore section, each of said pins has a pair of opposite ends spaced apart in the axial direction of said pins, the opposite ends of said pins remain spaced radially outwardly from said conically shaped inner surface and extend outwardly of said radially outer surface, means located outwardly from said radially outer surface and in contact with the opposite ends of said pins for spring biasing said pins intermediate the opposite ends thereof radially outwardly of said conically shaped inner surface so that intermediate the opposite ends said pins are arranged to engage in the grooves on the shank of the drilling or chiselling tool to be secured in said tool holder.