PURPOSE: To always carry out a stabilized edge preparation by moving a milling cutter, whose axial direction is perpendicularly held to the end face of a member to be machined, in the three dimensional directions by means of more than one feed motor while preparing said end face to a certain groove angle.
CONSTITUTION: When an outside edge preparation is to be carried out for, e.g., the end face 10a of a steel member 10 formed in an L-shape, first, a milling cutter 30 is set on the outside of the steel member 10 by means of feed motors 24, 26, 28. Then the cutter 30 is rotated by means of a motor 31 to start cutting while, at the same time, the cutter 30 is moved in the X direction through the feed motor 24. When the cutter 30 arrived at the bent part of the steel member 10, the rotation of the feed motor 24 is stopped while the rotation of the feed motor 26 is started, and the moving direction of the cutter 30 is changed 90° in the direction of Y while cutting of the end face 10a is carried out. Thereby, an always stabilized edge preparation can be conducted eliminating the need for monitoring by an operator.
KURODA HIROYUKI
TAKAHASHI KENJI
