Numerical controller with machining curve creating function

A numerical controller with a machining curve creating function which performs machining by creating a machining curve that is a curve for machining based on a command point sequence obtained from a machining program for a machine tool having a plurality of drive axes including at least two linear axes, interpolating the machining curve, and driving the drive axes to the interpolated positions on the machining curve, the numerical controller comprising:

• a segment curve creating unit which divides the command point sequence into a plurality of segments, and creates a segment curve that is a curve corresponding to a segment command point sequence of each of the segments, so that a distance of the segment curve from the segment command point sequence is within a permissible value set in advance and a maximum number of command points are included between a segment starting point that is a starting point of the segment command point sequence and a segment ending point that is an ending point of the segment command point sequence;
• and
• a machining curve creating unit which creates the machining curve by repetitively executing the process of the segment curve creating unit from a starting point to an ending point of the command point sequence, wherein
• the machining curve is interpolated and the drive axes are driven so as to move to the interpolated positions on the machining curve.