Scanning finger for a scanning device of a machine for the automatic sharpening of broaching or reaming tools

An apparatus for use in a scanning device of a machine for the automatic sharpening of a cutting tooth of a tool said cutting tooth having a free face, a cutting face and a rounded-off cutting edge, which machine has a horizontal slide for receiving said tool having cutting teeth to be sharpened and a vertical slide provided with at least one grinding spindle, said apparatus comprising a scanning finger movable relative to the scanning device and coupled to at least one member for emitting signals in a displacement-dependent manner for triggering drive mechanisms for said slides;

• the scanning finger including:
• (a) a scanning face having a scanning edge being undercut to form (b) an undercut face, said undercut face defined at one end by said scanning edge and at the other end by (c) a measuring edge, for resting on said tooth cutting face, extending upwardly from (d) a face downwardly offset from the scanning face and intended for ascertaining the cutting face of the cutting tooth;
• said undercut face extending for a distance so that the horizontal distance between said measuring edge and said scanning edge is larger than the largest possible rounding-off of the cutting edge, said scanning edge being capable of resting upon said free face of said cutting tooth.