Title:
PUNCHING METHOD AND PUNCHING DEVICE EMPLOYING HYDRO-FORM AND HYDRO-FORMED PART AND STRUCTURE BODY
Document Type and Number:
WIPO Patent Application WO/2008/050911
Kind Code:
A1
Abstract:
In a punching method also applicable to a thin hydro-form molding, a short tube
member is eliminated when a nut for tightening a bolt is fixed to a hydro-form molding,
the degree of difficulty of hydro-form molding does not rise when a nut is fixed,
and the nut is lengthened so that sufficient strength can be assured when the bolt
is tightened. A metal pipe is inserted into a split die with a punch which is movable
perpendicularly or obliquely to the pipe axis, has a thinner diameter at the distal
end than at the middle portion and is provided, on the periphery of the distal end,
with nuts having an inside diameter larger than the outside diameter at the distal
end but smaller than the outside diameter at the middle portion. After hydro-form
molding is performed, the punch is advanced and a portion of the hydro-form molding
is punched and then the nut is buried in the metal pipe while the nut is pushed at
the middle portion arranged in the rear of the nut.
Inventors:
MIZUMURA MASAAKI (JP)
SATO KOICHI (JP)
KURIYAMA YUKIHISA (JP)
SATO KOICHI (JP)
KURIYAMA YUKIHISA (JP)
Application Number:
PCT/JP2007/071360
Publication Date:
May 02, 2008
Filing Date:
October 26, 2007
Export Citation:
Assignee:
NIPPON STEEL CORP (JP)
MIZUMURA MASAAKI (JP)
SATO KOICHI (JP)
KURIYAMA YUKIHISA (JP)
MIZUMURA MASAAKI (JP)
SATO KOICHI (JP)
KURIYAMA YUKIHISA (JP)
International Classes:
B21D39/00; B21D26/033; B21D26/035; B21D28/10
Foreign References:
JP2001300655A | 2001-10-30 | |||
JPS3534116Y1 | ||||
JPS353814Y1 | ||||
JPH07139532A | 1995-05-30 | |||
JP2001099125A | 2001-04-10 | |||
JP2002045926A | 2002-02-12 | |||
JP2003334625A | 2003-11-25 | |||
JP2005297060A | 2005-10-27 |
Other References:
See also references of EP 2077168A4
Attorney, Agent or Firm:
AOKI, Atsushi et al. (Toranomon 37 Mori Bldg. 5-1,Toranomon 3-chome, Minato-k, Tokyo 23, JP)
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