METHOD FOR MILLING POLYHEDRAL HOLES Russian patent published in 1994 - IPC

FIELD: cutting. SUBSTANCE: part is machined by a trihedral tool, which sides are the sides of an equilateral triangle which length is equal to the length of the side of the machinable hole. A center hole is preliminary drilled in the part. The tool is set in rotation, and the part is moved along a trajectory which is an equilateral quadrangle. The tool rotation direction and its angle of rotation are matched with the displacement of the part depending on the type of the machinable hole: the number and the size of its sides. The diameter of the central hole in the part is equal to the largest size of the zone non-overlapped by the tool while machining. EFFECT: improved quality. 5 cl, 9 dwg, 3 tbl