Machine Tool And Method Of Operating A Machine Tool

Abstract

The invention relates to a machine tool, hi particular a lathe grinding machine, comprising a tool spindle, a spindle motor and a tool clamped in a covet, with which tool a workpiece may be machined which may be moved in several axes relative to the tool, and comprising a control device for the tool spindle which controls the spindle motor. A spindle load detection device (24) which is connected with the control device (20) is provided and the control device (20) compares the output signal (26) of the spindle load detection device (24) with a predetermined threshold value (50), said threshold value (50) being below, in particular at least 20% below, the breaking load (54) of the tool (18). The control device (20) turns off the spindle motor (14) when the output signal (26) of the spindle load detection device (24) exceeds the threshold value (50).

Dependencies are inferred from the claim text.