Machine tool with calibration device for calibrating a meshing sensor

A machine tool for machining pre-toothed workpieces has a workpiece carrier (20), a workpiece spindle (21) with a workpiece spindle housing (211) and a workpiece spindle shaft (212) rotatable about a workpiece spindle axis (A). Further, the machine tool has a meshing sensor (1) which is designed to determine a phase position of teeth of a workpiece (23) rotating about the workpiece spindle axis (A), a calibration piece (10) which is located at a defined calibration point (CM) relative to the workpiece spindle (21), and a sensor controller which is designed to perform the following procedure: Moving the meshing sensor (1) relative to the workpiece spindle (21) into a calibration position in which the meshing sensor (1) is located at the calibration piece (10); determining a response behavior of the meshing sensor (1) by the sensor controller (3) moving the meshing sensor (1) relative to the calibration piece (10) and meanwhile receiving sensor calibration signals of the meshing sensor (1), and moving the meshi