Title:
METHOD FOR BENDING METAL TUBE IN SMALL RADIUS OF CURVATURE
Document Type and Number:
Japanese Patent JP3449491
Kind Code:
B2
Abstract:
PURPOSE: To provide a bending method which can form a metal bent tube with a small radius of curvature and high quality without generating crush or wrinkle on the bent part.
CONSTITUTION: A bending process that a like work is bent with a 1st curvature without generating crush or wrinkle on the front surface, a die forming process that the work bent with the 1st curvature is formed with pressing with a lower die 13 having a die surface bent to a prescribed angle of bending θ with a 2nd curvature and an upper die 12 and the bending part is formed to a bent tube 10b bent to the prescribed angle θ with a 2nd curvature, and a shaping process shaping an internal surface of the bent tube 10c by forcibly inserting the punch regulating rods 15a, 15b inside the bent tube 10b from both ends of the bent tube 10b are provided. Therefore, no buckling is produced on the bent portion and the bent tube with high quality and without crush or wrinkle on the surface can be easily manufactured.
Inventors:
Amano longevity
Shigeru Suzuki
Shigeru Suzuki
Application Number:
JP29225192A
Publication Date:
September 22, 2003
Filing Date:
October 06, 1992
Export Citation:
Assignee:
Usui Kokusai Sangyo Co., Ltd.
International Classes:
B21D9/07; B21D9/08; (IPC1-7): B21D9/07; B21D9/08
Domestic Patent References:
| JP4939555A |
Attorney, Agent or Firm:
Yoshiteru Oshida