| 摘要 |
PROBLEM TO BE SOLVED: To provide a numerical controller for a machine tool, in which a load imposed on a tool in starting cutting when the tool comes in contact with a workpiece can be reduced by accelerating a feed speed of a shaft moving the tool and rotation speed of a main spindle for rotatively driving the tool at an optimal and optional speed ratio, respectively, in accordance with a tool position in an optional area, in a machine tool for performing drilling.SOLUTION: In the numerical controller for the machine tool, a feed speed of a feed shaft and rotation speed of a main spindle are changed according to a current position of the rotary tool, in optional areas of a front part and a rear part of a contact position where a workpiece and the rotary tool come in contact with each other. Thereby, according to the current position of the rotary tool, the feed speed of the feed shaft and the rotation speed of the main spindle are accelerated at an optimal and optional speed ratio respectively, and a load imposed on the tool in starting cutting when the tool comes in contact with the workpiece can be reduced. |
