• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.146-149
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• 2002

컨덴서식 저항 용접기는 용접에 필요한 에너지를 전해컨덴서에 축척 시킨 후 이것을 순시에 용접변압기로 방전하여 큰 용접전류를 흘리게 된다. 아날로그 제어방식에 의한 기존 컨덴서 용접 시스템은 용접 세팅이 어려웠으며, 시스템의 소손 가능성이 높았고, 크기면에서도 비대해질 우려가 있었다. 이에 비해 디지털제어방식의 중앙집중식 자동화시스템은 사용자가 세팅을 쉽게 할 수 있으며, 전원을 제어함에 따라서 전력소비를 최소화 할 수 있다. 본 연구에서는 마이크로프로세서를 이용한 디지털제어방식의 중앙 집중식 컨덴서식 저항용접 시스템을 제안한다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1999년도 특별강연 및 추계학술발표대회 개요집
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• pp.3-8
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• 1999

• Journal of Welding and Joining
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• 제17권5호
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• pp.83-88
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• 1999

In this paper resistance projection weldability of Zn coated steels with post treatment has been discussed. Projection welding was performed by a condenser discharge type power source which was equipped with welding parameter monitoring system. Mechanical test results indicated that the effect of post coatings on the projection front changed showing very small very small spattering at the weld strength was negligible. However, contamination rate of the block electrode varied depending on the post treatment coatings. Test results also showed that projection height before welding should be kept to be 80-100% of the specimen thickness as far as the surface quality was taken into consideration. Based on the high speed photography, discharge condition at the beginning stage of the welding process. It was considered that the spattering reduced the weld strength slightly at the optimum heat input range.

• Journal of Welding and Joining
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• 제15권6호
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• pp.49-56
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• 1997

Effect of process parameters on the quality of condenser discharge weld for coated sheet steels was discussed. The welding specimens were coated with pure Zn of 20/20 g/m2 in the production line. Direct measurements of welding parameters such as the discharge current, the pressures and the voltage drop across the electrodes were carried out with welding process monitoring system. High speed camera was also utilized to analyze the weld formation process. Test results indicated that the relation between weld strength and applied energy was stabilized at the acceptable welding heat input range. It was thought that the acceptable welding heat input should be redefined based on the monitored data because the calculated value of the welding heat input could hardly be utilized if the discharge condition was changed. Mechanical test results and high speed photographs showed that expulsion deteriorated the weld quality and the strength at the same time especially when the size of the spatter was large enough to carry the molten metal, which should form the nugget, out of the welding spot. Results also demonstrated that the discharge current should be applied at the appropriate time during the process because sufficient nugget was not produced if the time was deviated from the optimum range.