Toolholder for a machine tool

An adapter for allowing a machine toolholder having an outer annular supporting flange of a first diameter with a first conical surface converging downwardly to be used in a machine including (a) a tool carrying spindle, (b) a gripper for transporting toolholders between a magazine and the tool carrying spindle, the gripper having an inner annular groove of a second diameter for mating with and supporting a toolholder, lifting means for vertically lifting the griper and (d) pulling means arranged in the spindle for pulling the toolholder into operative engagement wtih the spindle, said adapter comprising:

• an annular insert having a central aperture defined by a second conical surface converging downwardly, said second surface being adapted to mate with said outer annular supporting flange of said toolholder, the outer surfaces of said insert being configured to mate with the inner annular groove of the gripper whereby in one case the toolholder may be supported by a magazine or gripper, with said first conical surface frictionally engaging and resting upon said second conical surface and in a second case, the toolholder may be separated therefrom by the pulling means as it pulls the toolholder into operative engagement with the spindle.