Abstract: An end surface 820 of a work 80 gripped by a chuck 50 equipped to a main spindle of a lathe-type machine tool is machined, and at the same time has a screw hole 830 formed thereto. The jig plate 60 is provided with a main body 600 having a fixing surface 630 and an inverse tapered portion 610. The jig plate 60 is provided with a bolt 620, and is fixed to the work 80 by a torque wrench tool 70. A chuck claw 122 of a chuck 120 of the second main spindle grips the inverse tapered portion 610 and processes the remaining surfaces of the work.

Abstract: An end surface 820 of a work 80 gripped by a chuck 50 equipped to a main spindle of a lathe-type machine tool is machined, and at the same time has a screw hole 830 formed thereto. The jig plate 60 is provided with a main body 600 having a fixing surface 630 and an inverse tapered portion 610. The jig plate 60 is provided with a bolt 620, and is fixed to the work 80 by a torque wrench tool 70. A chuck claw 122 of a chuck 120 of the second main spindle grips the inverse tapered portion 610 and processes the remaining surfaces of the work.

Abstract: A casing is rotatably and stoppably held on tool supporting means, a rotary tool spindle is rotatably supported on the casing so as to have a shifted rotary center with respect to the rotary center of the casing, power transmission means is rotatably supported on the casing, and the power transmission means and the rotary tool spindle are engaged through eccentric engagement means. The movement of the rotary tool in the Y-axis direction is performed by integrally rotating the casing and the rotary tool spindle. The machining is performed by rotating the power transmission means in the state where the casing is held stationary, thereby to rotate the rotary tool with respect to the stationary casing through the eccentric engagement means.