Provided is a waveform display device that can easily designate an analysis target range just by selecting a location to be analyzed with regard to a tool trajectory. This waveform display device comprises: a positional information acquisition unit that acquires, from a control device that controls a machine tool, motor positional information for a drive shaft of the machine tool during workpiece machining; a shaft information setting unit that sets shaft information indicating the shaft configuration of the drive shaft of the machine tool; a tool trajectory display unit that calculates the trajectory of a tool tip point during workpiece machining by a tool mounted on the machine tool on the basis of the motor positional information and the shaft information and displays the trajectory as a waveform; an analysis target setting unit that sets an analysis target position relating to the trajectory of the tool tip point; an analysis target range generation unit that generates and displays an analysis target range containing a solid body including the set analysis target position; and a measurement point sorting unit that sorts out and displays a measurement point included in the analysis target range generated by the analysis target range generation unit from within the trajectory of the tool tip point.

The present invention addresses the problem of providing a display device with which it is possible to display a location in a machining path at which a step occurs that is large enough to affect machining precision without actual machining, and to be able to accurately and at low cost predict the occurrence of the step in the machining path. The problem can be resolved with a display device with which: time-series data is acquired for the position of a driven body or an electric motor on each axis of a machine tool; machining paths are calculated based on the acquired time-series data for the position of the driven body or electric motor on each axis; based on the calculation result for the machining paths, a height reference plane is set for each machining path; the heights from the reference planes of adjacent machining paths are compared; and the locations on the machining paths in which height differences occur that are greater than or equal to a set threshold value are displayed.

Provided is a waveform display device that can easily designate an analysis target range just by selecting a location to be analyzed with regard to a tool trajectory. This waveform display device comprises: a positional information acquisition unit that acquires, from a control device that controls a machine tool, motor positional information for a drive shaft of the machine tool during workpiece machining; a shaft information setting unit that sets shaft information indicating the shaft configuration of the drive shaft of the machine tool; a tool trajectory display unit that calculates the trajectory of a tool tip point during workpiece machining by a tool mounted on the machine tool on the basis of the motor positional information and the shaft information and displays the trajectory as a waveform; an analysis target setting unit that sets an analysis target position relating to the trajectory of the tool tip point; an analysis target range generation unit that generates and displays an analysis target range containing a solid body including the set analysis target position; and a measurement point sorting unit that sorts out and displays a measurement point included in the analysis target range generated by the analysis target range generation unit from within the trajectory of the tool tip point.