Abstract: The positions of at least three points, which are circumferentially, and equiangularly, offset from each other, of a peripheral face of a workpiece set on a rotary table are measured using a position detection probe. The amount of runout of the axis of the workpiece and a phase position of the workpiece, at which the runout amount is largest, are calculated from the measured positions of the equiangularly offset points. The rotary table is turned to set the largest runout phase position of the workpiece in a position opposed to a workpiece contact of a centering apparatus. The relative positions of the workpiece and a position detection block are calculated using the position detection probe. The workpiece is centered by moving a centering shaft member of the centering apparatus such that the workpiece contact pushes the workpiece by a distance corresponding to the runout amount.

Abstract: It is an object of the present invention to provide a machine tool with a rest apparatus having high supporting stiffness of a workpiece by the rest apparatus and having flexibility to machine a plurality of kinds of the workpieces selectively and to provide a machining method of the machine tool with the rest apparatus. The machine tool with the rest apparatus comprising a base 10, a spindle head 20 mounted on the base 10 to hold rotatably one end of a workpiece W, a tail stock 30 mounted on the base 10 to be faced to the spindle head 20 and to hold rotatably the other end of the workpiece W, first rest apparatus 52 mounted between the spindle head 20 and the tail stock 30 and fixed to the base 10 un-movably to support the workpiece W, and second rest apparatus 53 mounted between the spindle head 20 and the tail stock 30 and movably mounted on the base 10 to support said workpiece W.

Abstract: The positions of at least three points, which are circumferentially, and equiangularly, offset from each other, of a peripheral face of a workpiece set on a rotary table are measured using a position detection probe. The amount of runout of the axis of the workpiece and a phase position of the workpiece, at which the runout amount is largest, are calculated from the measured positions of the equiangularly offset points. The rotary table is turned to set the largest runout phase position of the workpiece in a position opposed to a workpiece contact of a centering apparatus. The relative positions of the workpiece and a position detection block are calculated using the position detection probe. The workpiece is centered by moving a centering shaft member of the centering apparatus such that the workpiece contact pushes the workpiece by a distance corresponding to the runout amount.

Abstract: It is an object of the present invention to provide a machine tool with a rest apparatus having high supporting stiffness of a workpiece by the rest apparatus and having flexibility to machine a plurality of kinds of the workpieces selectively and to provide a machining method of the machine tool with the rest apparatus. The machine tool with the rest apparatus comprising a base 10, a spindle head 20 mounted on the base 10 to hold rotatably one end of a workpiece W, a tail stock 30 mounted on the base 10 to be faced to the spindle head 20 and to hold rotatably the other end of the workpiece W, first rest apparatus 52 mounted between the spindle head 20 and the tail stock 30 and fixed to the base 10 un-movably to support the workpiece W, and second rest apparatus 53 mounted between the spindle head 20 and the tail stock 30 and movably mounted on the base 10 to support said workpiece W.