Tool travel path creating method

A method for controlling a travel path of a tool using a control device, said method comprising the steps of:

• reading a stored program;
• determining whether or not any correction command is included in the read program;
• determining whether or not an interior angle between a first vector, from a starting point of correction to a work starting point, and a second vector, from the work starting point to a work ending point, is acute when any correction command is included in the read program;
• if said interior angle is acute, creating a tool travel path to be corrected in accordance with the following steps:
• calculating and storing data for a third vector starting from the work starting point and with a direction perpendicular to said first vector and the same length as the radius of the tool and ending at an ending point;
• calculating and storing data for a fourth vector starting from the work starting point and formed by adding said second vector to an intermediary vector with the same direction as said second vector and the same length as the radius of the tool and ending at an ending point;
• calculating and storing data for a fifth vector starting from the work starting point and with a direction perpendicular to said second vector and the same length as the radius of the tool and ending at an ending point;
• and
• calculating and storing data for a sixth vector starting from the work starting point and with the same direction as said first vector and a length of 2.sup.1/2 of the radius of the tool and ending at an ending point;
• and
• driving a servo motor to cause the tool to travel along the end points of the third to sixth vectors.

A method for controlling a travel path of a tool using a numerical control device, said method comprising the steps of:

• reading a stored control program;
• determining whether or not a correction command is included in said read control program;
• determining, responsive to a determination that a correction command is included, whether or not an interior angle between a first vector, extending from a starting point of correction to a work starting point, and a second vector, extending from the work starting point to a work ending point, is acute;
• responsive to a determination that said interior angle is acute:
• determining and storing a plurality of vectors each extending from the work starting point to a respective ending point along different predetermined directions;
• creating a tool travel path to be corrected in accordance with said plurality of vectors;
• and
• driving a servo motor to cause the tool to travel successively along the ending points of said plurality of vectors.