Numerical controller

A numerical controller comprising:

• a memory for storing a path table in which a speed and a position of a spindle are associated with a time serving as a reference, respectively;
• speed control executing means for reading out the values of the reference and the speeds of the spindle in succession from the path table and controlling the spindle speed in association with the value of the reference;
• contour control executing means for reading out the values of reference and the positions of the spindle in succession from the path table and controlling the spindle position in association with the value of the reference;
• position detecting means for detecting a rotational position of the spindle;
• means for reading out from the path table a command R32 for switchover from speed control to contour control, set for the value La of the reference in the path table prior to the value Lb of the reference for which a start of contour control by the contour control executing means is set, and obtaining from the position detecting means a position Xa of the spindle corresponding to the value La of the reference for which the command R32 for switchover is set;
• connection spindle speed determination means for determining a speed V for moving the spindle from the obtained position Xa at which the switchover command R32 is set to the position Xb at which the contour control is started, based on a spindle speed Sa obtained when the value La of the reference for which the switchover command R32 is set is reached and a spindle speed Sb at which the contour control is started;
• and
• spindle drive means for driving the spindle at the spindle speed determined by the connection spindle speed determination means from the position Xa at which the switchover command R32 is set to the position Xb at which the contour control is started.