| 摘要 |
PURPOSE:To eliminate sliding between the inside surface of a thin walled metallic cylinder and plural hourglass rolls having the same shape in a flange forming head for expanding forcibly the end part of said cylinder toward the outside by installing pivotally said rolls in the specific direction with respect to the center of a main revolving shaft. CONSTITUTION:A main revolving shaft 11 is of a T shape and its head part is so constituted as to guide an hourglass roll groups 14 by expanding the head part and forcing the same into the end part of a metallic cylinder 15. The seat 12 of each roll 14 is tray-shaped and is securely fitted via a sleeve onto the shaft 11 in the direction where the roll recesses toward the head part of the shaft 11. The bearing 13 of the roll 14 is a spherical bearing and the axial center 13' converges in a bevel shape into one point on the axial center 11'. The roll 14 is pivotally fitted on the bearing 13 along the center 13' between the head part of the shaft 11 and the annular build-up of the seat 12. Such head is advanced into the end part of the cylinder 15 while the head is rotated around the shaft 11 to expand forcibly the end part of the cylinder, thereby forming a flange 16. The inside surface of the cylinder 15 is kept free from rubbing and consequent flawing by the surface of the rolls 14 and the wear of surfaces of the rolls is lessened. |
