Title:
ホットプレス製品の製造方法
Document Type and Number:
Japanese Patent JP6978263
Kind Code:
B2
Abstract:
A method for manufacturing a hot pressed product by heating a sheet material and quenching the sheet material while molding the sheet material includes a hole forming step of forming a pilot hole in the sheet material; a heating step of heating the sheet material in which the pilot hole is formed; and a molding step of forming a burred portion at the pilot hole by using a burring punch included in a die set while molding the sheet material in the die set. The pilot hole has an opening shape in which convex portions and concave portions are alternately arranged. A diameter of a circumscribed circle that is in contact with the convex portions is greater than a punch diameter of the burring punch. A diameter of an inscribed circle that is in contact with the concave portions is less than the punch diameter of the burring punch.
Inventors:
Hiroaki Takishima
Application Number:
JP2017183596A
Publication Date:
December 08, 2021
Filing Date:
September 25, 2017
Export Citation:
Assignee:
Topre Corporation
International Classes:
B21D19/08; B21D22/20; B21D43/00; B23K26/384
Domestic Patent References:
| JP2006110609A | ||||
| JP2004330208A | ||||
| JP63164860U | ||||
| JP2010075933A | ||||
| JP2014004625A |
Foreign References:
| US6293134 | ||||
| KR1020130063779A |
Attorney, Agent or Firm:
Hidekazu Miyoshi
Shunichi Takahashi
Masakazu Ito
Toshio Takamatsu
Shunichi Takahashi
Masakazu Ito
Toshio Takamatsu