Method for forming press-formed parts with reduced springback

Patent metadata

Field	Value
Publication number	US-10040112-B2
Application number	US-201314421255-A
Country	US
Kind code	B2
Filing date	Aug 28, 2013
Priority date	Aug 31, 2012
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A springback-reduced part formed by performing a springback reduction on a press-formed part that is formed by a press forming of a blank sheet made of a metal sheet. The springback-reduced part is formed by setting each element of an analytic model of the press-formed part to a stressed state that causes a springback, performing an optimization analysis for shape to detect a portion of the press-formed part that highly contributes to the rigidity thereof, applying a rigidity improving means on a specific portion of the press-formed part on the basis of the detected portion, and performing the press forming.

First claim

The invention claimed is:

1. A method for manufacturing a springback-reduced part, the method comprising:
an analytic model forming step including forming an analytic model of a press-formed part with elements, the elements including at least one of plane elements and solid elements;
a stressed-state setting step including setting each of the elements of the analytic model to a stressed state that causes a springback;
a rigidity-contributable-portion detecting step including performing an optimization analysis on the analytic model with the elements set to the stressed state in the stressed-state setting step to detect a portion of the press-formed part that contributes to the rigidity of the press-formed part;
a rigidity improving step including performing a rigidity improving method on a specific portion of a blank sheet on a basis of the portion of the press-formed part that contributes to the rigidity of the press-formed part, which is detected in the rigidity-contributable-portion detecting step; and
a press-forming step including performing a press forming on the blank sheet, wherein:
the method reduces springback by increasing rigidity of the specific portion of the blank sheet without suppressing occurrence of residual stress during press forming of the part;
the optimization analysis includes analyzing the analytic model of the press-formed part to leave minimum elements required for satisfying given analytic conditions and determining the portion of the press-formed part that contributes to the rigidity of the press-formed part so as to only include the minimum elements; and
the rigidity improving method in the rigidity improving step is performed by removing the specific portion of the blank sheet to make a removed portion and fitting a member having a Young's modulus higher than a Young's modulus of the specific portion of the blank sheet into the removed portion such that the member is integrated with the blank sheet.

2. The method for manufacturing the springback-reduced part according to claim 1 , wherein the rigidity improving method in the rigidity improving step further comprises using a die to provide at least one of a protruding shape and a recessed shape to the member.

3. The method for manufacturing the springback-reduced part according to claim 1 , wherein the member has a thickness larger than a thickness of the specific portion of the blank sheet.

4. The method for manufacturing the springback-reduced part according to claim 1 , wherein the rigidity improving method in the rigidity improving step further comprises bonding another sheet to the member.

Assignees

• Jfe Steel Corp

Inventors

• Saito Takanobu

Classifications

• G06F2113/24

  Sheet material · CPC title

• G06F30/23

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title

• B21D22/20

  Deep-drawing (special deep-drawing arrangements in, or in connection with, presses B21D24/00) · CPC title

• B21D22/26

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

• G06F17/11

  for solving equations {, e.g. nonlinear equations, general mathematical optimization problems (optimization specially adapted for a specific administrative, business or logistic context G06Q10/04)} · CPC title