Abstract: An apparatus for machining a circumferential surface defining a cylindrical bore of a workpiece, the apparatus including a tool holder rotatable about a first rotation axis, and a form roller supported on the tool holder so as to be rotatable about a second rotation axis parallel to a central axis of the cylindrical bore of the workpiece. The form roller has a diameter smaller than a diameter of the cylindrical bore of the workpiece and is adapted for forming a plurality of microscopic recesses on the circumferential surface defining the cylindrical bore of the workpiece.

Abstract: A micro-roll forming device for providing a cylindrical blank metal article with a minute convexoconcave bearing surface, comprises a powered article holding structure that, when energized, rotates the cylindrical blank metal article about its axis; a forming tool that includes a form roller with a corrugated circular ridge; a tool holding structure that holds the forming tool in such a manner that the corrugated circular ridge of the form roller is directed toward and in contact with an outer surface of the cylindrical blank metal article rotatably held by the article holding structure; a biasing member that is incorporated with the tool holding structure to press the form roller against the outer surface of the cylindrical blank metal article with a given pressing force; and a powered moving structure that, when energized, moves at least one of the article holding structure and the tool holding structure in such a manner that the selected one moves in both a first direction perpendicular to an axis of the u

Abstract: A high smoothness grinding process for obtaining a highly smooth surface of a metal material member. The process includes grinding an outer peripheral surface of a cylindrical or generally cylindrical metal material member by using a super abrasive grain grinding wheel in a condition in which a value [a peripheral speed of the grinding wheel/a peripheral speed of the metal material member] is not larger than 100, the grinding serving as a main grinding step.

Abstract: An apparatus for machining a circumferential surface defining a cylindrical bore of a workpiece, the apparatus including a tool holder rotatable about a first rotation axis, and a form roller supported on the tool holder so as to be rotatable about a second rotation axis parallel to a central axis of the cylindrical bore of the workpiece. The form roller has a diameter smaller than a diameter of the cylindrical bore of the workpiece and is adapted for forming a plurality of microscopic recesses on the circumferential surface defining the cylindrical bore of the workpiece.

Abstract: A high smoothness grinding process for obtaining a highly smooth surface of a metal material member. The process includes grinding an outer peripheral surface of a cylindrical or generally cylindrical metal material member by using a super abrasive grain grinding wheel in a condition in which a value [a peripheral speed of the grinding wheel/a peripheral speed of the metal material member] is not larger than 100, the grinding serving as a main grinding step.

Abstract: A micro-roll forming device for providing a cylindrical blank metal article with a minute convexoconcave bearing surface, comprises a powered article holding structure that, when energized, rotates the cylindrical blank metal article about its axis; a forming tool that includes a form roller with a corrugated circular ridge; a tool holding structure that holds the forming tool in such a manner that the corrugated circular ridge of the form roller is directed toward and in contact with an outer surface of the cylindrical blank metal article rotatably held by the article holding structure; a biasing member that is incorporated with the tool holding structure to press the form roller against the outer surface of the cylindrical blank metal article with a given pressing force; and a powered moving structure that, when energized, moves at least one of the article holding structure and the tool holding structure in such a manner that the selected one moves in both a first direction perpendicular to an axis of the u

Abstract: A rotary assembly for traction drives, including a plurality of rolling elements having a rotation axis and traction contact surfaces around the rotation axis and associating with each other to transmit a motive power between the rolling elements via a traction oil film formed between the traction contact surfaces, in which at least one of the traction contact surfaces has a microstructure with irregularities which sizes are larger than a thickness of the traction oil film. The process for the traction contact surface is also disclosed.