DISCRIMINATING DEVICE

PURPOSE:To eliminate the necessity for an attachment and/or an actuator for only use, by concentrically providing a guide rod on a tool holder while holding a tapered cone to said guide rod and detecting the hole of a workpiece to be measured and discriminated by said tapered cone. CONSTITUTION:A discriminating tool 8 is taken out from a tool magazine 6 and mounted to a spindle 4. And a device, advancing a spindle head 3, fits a tapered cone 14 to a hole H of a workpiece W. the device, in which the tapered cone 14 fitted to the hole provides a different fitting quantity in accordance with a size of the hole, actuates a work discriminative confirming unit 9, provided in a side of the spindle head 3, by a working member 17 in accordance with the fitting quantity of said tapered cone 14. And the device, after it discriminates the work to be confirmed, performs machining by storing the discriminating tool 8 in the tool magazine 6 while setting a tool holder 7, corresponding to the hole H to be machined, to the spindle 4. Accordingly, the discriminating tool 8 can be stored in the tool magazine, while the necessity for an only use attachment and/or actuator, for retracting the discriminating tool when machining is performed, is eliminated.