Numerical control device inspecting screw holes

A numerical control device controlling a feed-axis motor and a main-axis motor that drive a main axis of a machining tool that performs screw-hole machining on a workpiece based on a machining program, wherein

• a screw-hole inspection gauge is attachable to the main axis of the machining tool, and
• the numerical control device comprises:
• a control unit that performs control in such a way that the feed-axis motor and the main-axis motor that drive the main axis with the screw hole inspection gauge attached thereto perform a screw-hole inspection operation based on the machining program;
• and
• a determining unit that determines acceptance/defect of inspection of a screw hole machined on the workpiece based on a condition of the feed-axis motor or a condition of the main-axis motor during control by the control unit, further comprising
• a soft floating setting unit that lowers a torque limit of the feed-axis motor and a torque limit of the main-axis motor before the screw-hole inspection gauge is inserted into the screw hole machined on the workpiece, and makes a limit of a positional deviation amount of the feed-axis motor changeable temporarily, wherein
• in insertion of the screw-hole inspection gauge into the screw hole machined on the workpiece, the control unit drives the feed-axis motor in a direction that the screw-hole inspection gauge is inserted into the screw hole, and when the positional deviation amount of the feed-axis motor exceeds the limit of the positional deviation amount of the feed-axis motor, the control unit temporarily stops the feed-axis motor, rotates the main-axis motor in a screw-in direction, and re-drives the feed-axis motor at a time point at which the positional deviation of the feed-axis motor is eliminated.