Abstract: A roll bending apparatus includes: a roll pair formed by a pair of rolls disposed facing each other, the roll pair being configured to sandwich an elongated material between the rolls to perform forming on the elongated material; a slide mechanism configured to slide the roll pair in a first normal direction that is a direction normal to a conveying direction of the elongated material on a plane including the conveying direction; and a tilt mechanism configured to rotate the roll pair about a tilt axis that extends in a second normal direction that is a direction orthogonal to the conveying direction and the first normal direction. The slide mechanism further slides the roll pair to change a position of the roll pair relative to the tilt axis.

Abstract: A roll bending apparatus includes: a roll pair formed by a pair of rolls disposed facing each other, the roll pair being configured to sandwich an elongated material between the rolls to perform forming on the elongated material; a slide mechanism configured to slide the roll pair in a first normal direction that is a direction normal to a conveying direction of the elongated material on a plane including the conveying direction; and a tilt mechanism configured to rotate the roll pair about a tilt axis that extends in a second normal direction that is a direction orthogonal to the conveying direction and the first normal direction. The slide mechanism further slides the roll pair to change a position of the roll pair relative to the tilt axis.

Abstract: A roll bending apparatus includes: a roll pair formed by a pair of rolls disposed facing each other, the roll pair being configured to sandwich an elongated material between the rolls to perform forming on the elongated material; a slide mechanism configured to slide the roll pair in a first normal direction that is a direction normal to a conveying direction of the elongated material on a plane including the conveying direction; and a tilt mechanism configured to rotate the roll pair about a tilt axis that extends in a second normal direction that is a direction orthogonal to the conveying direction and the first normal direction. The slide mechanism further slides the roll pair to change a position of the roll pair relative to the tilt axis.

Abstract: Electro-unite tubes having different plate thicknesses or different diameters are breakdown-formed without changing the upper rolls and the lower rolls of the breakdown pass rolls each time. Each of breakdown pass rolls 12 includes an upper roll 12a having a convex curved surface and a lower roll 12b opposed to the upper roll 12a, the lower roll 12b being provided with a V-shaped concave portion 13. A gap is maintained between a metal band plate 11 and the deepest portion D in the concave portion 13, and the metal band plate 11 is in local contact with the lower roll 12b. The upper roll 12a can be moved up and down, and the distance between the end of the curved surface of the upper roll 12a and the deepest portion D in the concave portion 13 is adjusted depending upon the plate thickness and the diameter of the electro-unite tube to determine the curvature (R.sub.1 or R.sub.2) for forming the metal band plate 11.