US 12,440,886 B2
Variable die, and pressing apparatus and method
Jae-Wook Lee, Incheon (KR)
Assigned to POSCO CO., LTD, Pohang-si (KR)
Appl. No. 18/037,506
Filed by POSCO Co., Ltd, Pohang-si (KR)
PCT Filed Nov. 2, 2021, PCT No. PCT/KR2021/015627
§ 371(c)(1), (2) Date May 17, 2023,
PCT Pub. No. WO2022/119144, PCT Pub. Date Jun. 9, 2022.
Claims priority of application No. 10-2020-0165772 (KR), filed on Dec. 1, 2020.
Prior Publication US 2024/0009727 A1, Jan. 11, 2024
Int. Cl. B21D 37/02 (2006.01); B21D 22/06 (2006.01); B21D 37/04 (2006.01); B21D 37/12 (2006.01); B30B 15/00 (2006.01); B30B 15/04 (2006.01)
CPC B21D 37/02 (2013.01) 18 Claims
OG exemplary drawing
 
1. A variable die comprising:
a first lower die portion; and
a first upper die portion disposed above the first lower die portion,
wherein the first lower die portion includes:
a first lower die center portion, on which a material is seated, and including a first sensor unit; and
a first lower die side part installed on a side surface of the first lower die center portion,
the first lower die side part includes:
an inner member having an inclined surface close to the first lower die center portion from top to bottom; and
a driving unit moving the inner member in a first direction, the first direction is a direction toward the first lower die center portion,
the first upper die portion includes:
a first upper die center portion disposed above the first lower die center portion, and the first upper die center portion moving downwardly toward the first lower die center portion; and
a first upper die side part installed on a side surface of the first upper die center portion, the first upper die side part is moving downwardly guided by the inclined surface and rotatably moving to the side surface of the first lower die center portion,
the first sensor unit measures a forming distance, the forming distance is a distance from the first sensor unit to the material, and
the driving unit is driven based on the forming distance to adjust a correction distance, the correction distance is a moving distance of the inner member.
 
15. A pressing method comprising:
a first pressing operation of forming a first material with a variable die under a forming condition determined by a first set distance, An, where n is a number of repetitions;
a forming distance measuring operation of measuring a first forming distance, Bn, the first forming distance is a distance between the first material and a first sensor unit of the variable die;
a set distance correcting operation of determining a second set distance, An+1, the second set distance is a set distance for a following round, based on a difference between the first set distance and the first forming distance; and
a second pressing operation of forming a second material following the first material with the variable die under a forming condition determined by the second set distance.