Abstract: A movable die 18 including a first groove 52 and a second groove 54 that extend in a direction in which hemming is performed is moved by a robot 22, and is positioned and set with respect to a wheel arch portion 16 in a vehicle 12 on a production line 14. The movable die 18 is mounted, positioned and fixed with respect to the vehicle 12 by a clamping mechanism 58. A guide roller 32 is rolled while the guide roller is engaged with the first groove 52, and a flange 17 is inclined by a conical surface of a tapered roller 38 of a hemming roller 30 that moves in an interlocking manner with the guide roller 32. Next, the guide roller 32 is rolled while the guide roller is engaged with the second groove 54, and the flange 17 is bent by a cylindrical surface of a cylindrical roller 40 of the hemming roller 30. The movable die 18 is separated from the vehicle 12 after the hemming.

Abstract: In an initial state of roller hemming processing, an erected flange 65 begins to be bent by a roller 48. At this time, a first plate 63 and a receiving face 15 are brought into tightly contact with each other at a contact point 70 between the roller 48 and the erected flange 65 by strongly pinching by the roller 48 and an auxiliary roller 51. On the other hand, in portions other than the contact point 70, the receiving face 15 tends to be separated from the first plate 63 by reaction. Since slider blocks 22 and 22 are movable along rails 21 and 21 on a side of the receiving die 10, the receiving die 10 rotates clockwise in the drawing about the contact point 70. A tight contact in the contact point 70 is guaranteed as the receiving die 10 rotates about the contact point 70. As a result, the hemming processing with a good shape can be achieved without wrinkling, ruffling, or deformation.

Abstract: In an initial state of roller hemming processing, an erected flange 65 begins to be bent by a roller 48. At this time, a first plate 63 and a receiving face 15 are brought into tightly contact with each other at a contact point 70 between the roller 48 and the erected flange 65 by strongly pinching by the roller 48 and an auxiliary roller 51. On the other hand, in portions other than the contact point 70, the receiving face 15 tends to be separated from the first plate 63 by reaction. Since slider blocks 22 and 22 are movable along rails 21 and 21 on a side of the receiving die 10, the receiving die 10 rotates clockwise in the drawing about the contact point 70. A tight contact in the contact point 70 is guaranteed as the receiving die 10 rotates about the contact point 70. As a result, the hemming processing with a good shape can be achieved without wrinkling, ruffling, or deformation.

Abstract: A movable die 18 including a first groove 52 and a second groove 54 that extend in a direction in which hemming is performed is moved by a robot 22, and is positioned and set with respect to a wheel arch portion 16 in a vehicle 12 on a production line 14. The movable die 18 is mounted, positioned and fixed with respect to the vehicle 12 by a clamping mechanism 58. A guide roller 32 is rolled while the guide roller is engaged with the first groove 52, and a flange 17 is inclined by a conical surface of a tapered roller 38 of a hemming roller 30 that moves in an interlocking manner with the guide roller 32. Next, the guide roller 32 is rolled while the guide roller is engaged with the second groove 54, and the flange 17 is bent by a cylindrical surface of a cylindrical roller 40 of the hemming roller 30. The movable die 18 is separated from the vehicle 12 after the hemming.