METHOD FOR DETECTING REJECTS DURING PROCESSING OF IDENTICAL WORKPIECES AND ASSOCIATED NUMERICALLY CONTROLLED WORKPIECE PROCESSING APPARATUS

The invention relates to a method for detecting rejects during processing of identical workpieces (14) by means of a numerically controlled workpiece processing apparatus (10), comprising the following steps: a) processing a workpiece (14) according to the specification of a target tool path (34) for a tool (12) of the workpiece processing apparatus (10) and b) closed-loop control of a working distance (22) of the tool (12) from the workpiece (14) to a defined target distance such that during processing of the workpiece (14), the tool (12) is moved along the target tool path (34) on an actual, distance-controlled tool path (36), wherein according to the invention it is examined whether the distance-controlled actual tool path (36) deviates from the target tool path (34) which applies to said workpiece (14) at selected contour sections (40), in particular contour sections which lack tracking errors, by less than a predefined tolerance value. If yes, processing of the next workpiece (14) continues or, if no, a notification is output that the processed workpiece (14) has been identified as a reject.