To avoid unnecessary consumption of energy and enlargement of a face machining device.

For a face machining device, one end of roller chain 238 is joined to a moving part 232, while the other end is joined to a tool holder 110. By holding a sprocket wheel 236 to a rotating body 52 in a rotating way, and wrapping the center part of a roller chain 238 around the sprocket wheel 236, the centrifuge of the moving part 232 is reversed to transfer it to the tool holder 110. In machining a work piece by the face machining device, the centrifuge influencing on the tool holder 110 is offset for the centrifugal force of the moving part 232, thereby reducing a force to move the tool holder 110, thus avoiding unnecessary energy consumption and enlargement of the device.