Patent ID: 6477877
Filing Date: 2002-11-12
Classification: B21C,B21D,B24B,F16C,Y10T

Abstract:
A manufacturing tool inserted in a hole formed in a work piece for forming a fluid bearing groove on an inner peripheral surface of the hole, comprising:a tool shaft being rotated in the hole while being moved in an axial direction thereof; a plurality of balls rotatably supported on an outer peripheral face of the tool shaft, which are to be abutted against the inner peripheral surface of the hole to form the fluid bearing groove thereon in accordance with the movement of the tool shaft; a retainer detachable fitted on the outer peripheral face of the tool shaft so as to retain the balls on the tool shaft; a fixing member detachably fitted with the tool shaft so as to fix the retainer on the tool shaft, wherein the balls can be replaced when the fixing member and the retainer is detached from the tool shaft; and a ball bearing member accommodated in an axial hole formed in the tool shaft so as to be axially movable therein while bearing the balls in bearing recesses formed on an outer peripheral face thereof, wherein the bearing recesses are shaped such that the balls are situated at different positions therein in accordance with the direction of the axial movement of the tool shaft.