Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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A Study for the Improvement of Weld Quality Through Force Control of Servo Gun in Resistance Spot Welding using Robot

저항 점 용접 로봇에서 서보건의 가압력 제어를 통한 용접 강도 향상에 대한 연구

  • Park, Young-Whan (The BK21 Program for Research and Education in Mechanical Engineering, Hanyang University) ;
  • Lee, Jong-Gu (Precision Mechanical Engineering, Hanyang University) ;
  • Rhee, Se-Hun (Department of Mechanical Engineering, Hanyang University)
  • 박영환 (한양대학교 BK21 혁신설계 기계인력 양성사업단) ;
  • 이종구 (한양대학교 정밀기계공학과) ;
  • 이세헌 (한양대학교 기계공학부)
  • Published : 2006.12.31
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Abstract

Resistance spot welding is widely used for joining sheet metals in the automotive manufacturing process. Recently, servo-gun is used to increase the productivity and precise control the acting force. However, force control mechanisms have not been investigated with servo-guns until now. In this paper, it is proved that servo-motor current is proportional to torque and by experiment, experimental equation between servo-motor current and electrode force was derived. Algorithm for feedback control of electrode force was suggested using current measurement. In addition, applying soft touch method to this system the impact between electrode and specimen, which is the problem of air gun, could be reduced. Indentation made the force decrease in holding time of resistance spot welding. In order to overcome this problem, force compensation using the servo gun was used and it improved weld strength in good welding current range.

Keywords

References

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