Adjustment of Blank Holding Force Distribution Utilizing a Multi-Point Die Support System

Abstract:

In this study, the authors employ a multi-point die-support structure to hold the upper die for deep drawings in order to adjust the distribution of the blank holding force (BHF) so as to eliminate wrinkles. The developed multi-point support structure has 12 support cells (support units) between the upper die and the outer slide of a double-action press; the cells are metal cylinders working as springs. The support unit has a ball contact at the interface with the upper die, and the interface freely rotates and slides horizontally. The support unit has strain gauges on the side surface, and the bearing load at each unit can be determined, as well as the elastic deformation. The bearing load distribution is observed through a trial blow, and then the support units are manually relocated to better distribute the supporting points to create the appropriate BHF distribution. To demonstrate the efficiency of the suggested structure, the authors perform deep drawing with off-centered setting of a blank to create wrinkles intentionally. They then employ the multi-point die-support system, relocate the support units, and eliminate wrinkles.

• Periodical: Key Engineering Materials (Volumes 622-623)
• Pages: 1117-1123
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.622-623.1117
• Online since: September 2014
• Authors: Takahiro Ohashi*, Wan Tong
• Keywords: Blank Holding Force, Deep Drawing, Die Design, Wrinkle

References

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