Forming method of metal member excellent in shape freezing property

Patent metadata

Field	Value
Publication number	US-9248487-B2
Application number	US-201113697918-A
Country	US
Kind code	B2
Filing date	May 23, 2011
Priority date	May 25, 2010
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

When forming a hat-shaped cross section member having, on its cross section perpendicular to its longitudinal direction, vertical wall portions on both sides, and flange portions on both sides connected to the respective vertical wall portions, and a top sheet portion connected to the vertical wall portions on both sides, and having a bent portion bent in the longitudinal direction with the flange portions positioned outside by using punches and dices, a dice shoulder radius of the dice for obtaining the shape of the hat-shaped cross section member is set to R 0 , the hat-shaped cross section member is formed by the dice having a dice shoulder radius R 1 larger than the dice shoulder radius R 0 , and then the hat-shaped cross section member is formed by the dice having the dice shoulder radius R 0 .

First claim

The invention claimed is:

1. A forming method of a metal member, excellent in shape freezing property, being a method of forming the metal member having, on its cross section perpendicular to its longitudinal direction, vertical wall portions on both sides and flange portions connected to at least one of the vertical wall portions on both sides, and having a bent portion bent in the longitudinal direction with the flange portions positioned outside, by using punches and dices, the forming method comprising:
setting a dice shoulder radius of the dice for obtaining a final shape of the metal member to R 0 , forming an intermediate shape having, on its cross section perpendicular to its longitudinal direction, vertical wall portions on both sides and flange portions connected to at least one of the vertical wall portions on both sides, and having a bent portion bent in the longitudinal direction with the flange portions positioned outside by forming the metal member one time or a plurality of times by the dice having a dice shoulder radius R 1 larger than the dice shoulder radius R 0 , and then forming the final shape by forming the metal member by the dice having the dice shoulder radius R 0 ;
wherein a dice shoulder corresponds to a portion where the vertical wall portions and the flange portions are connected; and
wherein the dice shoulder radius R 1 is set to fall within a range of not less than 1.1R 0 nor more than 3.5R 0 .

2. The forming method of the metal member according to claim 1 , wherein the metal member has, on its cross section perpendicular to its longitudinal direction, vertical wall portions on both sides, flange portions connected to at least one of the vertical wall portions on both sides, and a top sheet portion connected to the vertical wall portions, and has a bent portion bent in the longitudinal direction with the flange portions positioned outside.

3. The forming method of the metal member according to claim 2 , wherein the metal member is a hat-shaped cross section member.

Assignees

• Daimaru Seiichi
• Nippon Steel & Sumitomo Metal Corp

Inventors

• Daimaru Seiichi

Classifications

• B21D22/26 Primary

  for making peculiarly, e.g. irregularly, shaped articles · CPC title

• B21D22/02

  Stamping using rigid devices or tools · CPC title

• B21D22/00 Primary

  Shaping without cutting, by stamping, spinning, or deep-drawing (otherwise than using rigid devices or tools or yieldable or resilient pads B21D26/00) · CPC title

• B21D37/10

  Die sets; Pillar guides · CPC title

• B21D5/01 Primary

  between rams and anvils or abutments · CPC title