US 12,090,541 B2
Press forming method and shape evaluation method for press formed part
Yusuke Fujii, Tokyo (JP); Masaki Urabe, Tokyo (JP); and Shunsuke Tobita, Tokyo (JP)
Assigned to JFE STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/799,782
Filed by JFE STEEL CORPORATION, Tokyo (JP)
PCT Filed Oct. 2, 2020, PCT No. PCT/JP2020/037619
§ 371(c)(1), (2) Date Aug. 15, 2022,
PCT Pub. No. WO2021/171678, PCT Pub. Date Sep. 2, 2021.
Claims priority of application No. 2020-029205 (JP), filed on Feb. 25, 2020.
Prior Publication US 2023/0100401 A1, Mar. 30, 2023
Int. Cl. B21D 22/26 (2006.01)
CPC B21D 22/26 (2013.01) 2 Claims
OG exemplary drawing
 
1. A press forming method for controlling a shape change of a press formed part over time after the press formed part springs back at a moment of a release from a press-forming die, the press forming method comprising:
a press forming step of press forming a metal sheet into the press formed part by using the press-forming die;
a die releasing step of releasing the press formed part, which is press-formed, from the press-forming die; and
a post-release die holding step of holding the released press formed part in a forming bottom dead center shape for 30 minutes or more by using the press-forming die.