| 摘要 |
PURPOSE:To prevent the reduction of thickness of a tube caused by bending by holding a tube with a bending die and a press die arranged on a press arm and performing bending operation of a tube successively by repeating advance and retreat of the press arm. CONSTITUTION:A bending arm 4 and a press arm 6 are attached to the pivot 3 of the body 2 of a tube bending device. A tube 1 is held by a clamp 5 of the bending arm 4 and pressed by a bending die 7 and a press die 8 of the press arm 6. A mandrel 12 is inserted in the tube 1, and a brace 13 and a wrinkle press 15 are brought into contact with the outer face of the tube 1. Bending of the tube 1 is performed by pressing the bracket 10 of the press arm 6 by a hydraulic cylinder. After bending to a proper angle, pressing of the tube 1 is released by the hydraulic cylinder 9, and the press arm 6 is returned to the original position. After pressing the press die 8 to the tube 1 by the hydraulic cylinder 9, the press arm 6 is advanced again to bend the tube 1. By performing bending work by repeating this operation properly, the reduction of thickness and the cracks that may be generated on the outer side of bending of the tube are prevented. |
