Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A Study on Process Characterization based on Vibration Signals Transmitted to the Mold in the Press Molding Process

프레스성형공정에서 금형에 전달되는 진동 신호에 기반한 공정특성 분석에 대한 연구

  • Junhan Lee (Solution Team, eMoldino. Inc.) ;
  • Jongsun Kim (Department of Research Mold & Die, Korea Institute of Industrial Technology)
  • 이준한 ((주)이몰디노 솔루션 팀) ;
  • 김종선 (한국생산기술연구원 금형성형연구부문)
  • Received : 2023.03.15
  • Accepted : 2023.03.31
  • Published : 2023.03.31
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Abstract

In this study, the vibration signal of the mold was measured and analyzed to monitor the process information and characteristics during the press molding process. A necklace-type picture frame mold was used for press molding, and the vibration signal was measured by GY-61 acceleration sensor module attached to the surface of the upper (movable) mold base. The change of the vibration signal of the mold according to press speed was analyzed. As a result, the vibration signal had a large change at five sections: "Holder contact", "Punch contact and start of pressing", "End of pressing", "Mold open", and "Demolding". The time difference between "Punch contact and start of pressing" and "End of pressing" means the pressing time which is the actual time the material is molded under pressing pressure. The time intervals for each section, represented by the time interval between "Holder contact" and "Punch contact and start of pressing", can be used to compare and evaluate the press speed applied to the process. By comparing the vibration signals at 60 rpm and 90 rpm, the amplitude at the section of "Punch contact and start of pressing" increased as the press speed increased. This result means that as the press speed increases, more force and pressure is applied to the material. Also, the peak values of the other sections were found to increase as the press speed increased. It was found that the pressing time, the time interval between "Punch contact and start of pressing" and "End of pressing", decreases as the pressing speed increases. Similarly, press speed factor, the time interval between "Holder contact", and "Punch contact and start of pressing", is found to be shorter. Therefore, based on the result of this study, the pressing time, press speed, pressing(punching) pressure of each cycle can be monitored by measuring the vibration signal of the mold. Also, it was confirmed that the level and trend of process information and characterization can be evaluated as the change of the mold vibration during press molding.

Keywords

Acknowledgement

본 연구는 중소기업벤처부의 스마트 제조혁신 기술개발사업(R&D)(Project No. RS-2022-00140364)의 지원으로 진행되었습니다.

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