Patent ID: 7610786

Claim:
An apparatus for forming microscopic recesses on a circumferential surface that defines a cylindrical bore in a workpiece, the apparatus comprising: a main shaft; a tool holder disposed on the main shaft so as to be in axial alignment with the main shaft, the tool holder being rotatable about a rotation axis together with the main shaft; a form roller support disposed on the tool holder, the form roller support including a support shaft parallel to the main shaft; a form roller supported on the support shaft of the form roller support so as to be rotatable together with the support shaft, the form roller being formed with microscopic projections on an outer peripheral surface thereof; a load applying member that applies a load to the form roller support in a radial direction of the form roller to press the microscopic projections of the form roller against the circumferential surface that defines the cylindrical bore in the workpiece under condition that the rotation axis of the tool holder is in alignment with a central axis of the cylindrical bore; and a rotational resistance varying member that varies rotational resistance of the form roller.