Patent ID: 8468917

Claim:
A machine tool comprising: a supporting device configured to support a workpiece in a manner that permits the workpiece to be rotated around a first axis; and a tool rest having a rotary shaft, the tool rest being configured to allow a rotary tool to be coupled to the rotary shaft in a manner that permits the rotary tool to be rotated around a second axis, the rotary shaft being adapted to be coupled to a boring tool for boring operations to machine an internal surface of the workpiece; wherein the tool rest is adapted to be turned around an axis perpendicular to the first axis; wherein the boring tool includes a tool holder adapted to be coupled to the rotary shaft and a bit which is angled with respect to an axis of the tool holder; and wherein the tool rest is turned around to be positioned at a specific oblique angle with respect to the first axis, so that a direction of the bit of the boring tool coupled to the rotary shaft of the tool rest is parallel to the first axis, the supporting device and the tool rest being relatively moved; whereby a boring operation, where an axis of a bored hole is parallel to the first axis, is performed to the workpiece rotated around the first axis with the tool rest positioned at the specific oblique angle with respect to the first axis.