Work for a drill with a pair of oil supply hole, and centering method of hole with work, as well as centering devices

摘要

PROBLEM TO BE SOLVED: To optimize the hole arrangement balance of a product obtained by grinding a tip taper surface being a blade mounting face by carrying out centering so as to allow a midpoint of a segment connecting hole centers of a pair of oil supply holes of a workpiece for a drill including the pair of the oil supply holes to coincide with a processing center position.;SOLUTION: A centering method is directed for grinding a cutting blade surface of an eccentric workpiece W₁ for the drill. The centering method includes: a first centering step for rotating the workpiece W₁ for the drill temporarily fixed by an eccentric clamp device by only an instruction angle by a workpiece rotating device in such a way that a position of a midpoint K is arranged on a specific arc passing through a processing center with an eccentric axis as a center while the spindle of a grinder is fixed not to be rotated; and a second centering step for rotating the eccentric axis by only an instruction angle in an instruction direction in such a way that the position of the midpoint K of the workpiece W₁ for the drill is arranged on the processing center being the axial core of the spindle with the eccentric axis as the center.;COPYRIGHT: (C)2010,JPO&INPIT