• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.2
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• pp.157-162
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• 2015

A large five-axis gantry-type machine performs cutting operations by moving the gantry, along with a bed. During operation, there are three sources of position (zig-zag) errors: 1) the position difference between two control motors on the X axis, 2) friction difference from the different column weights, and 3) torque of the rotating spindle. This study improved the performance of a gantry-type machine by analyzing these three error sources. We changed the mass of a column in the gantry structure and measured the effect on the friction result. We also studied the spindle torque influences on the movement performance of the gantry in relation to the spindle rotation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.310-315
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• 2011

General portal machine represents a distinct weak spot concerning their structural behavior because of long protruding structure components, such as saddles and rams. The weak point causes the deformation of the machine tool and consequently rises a severe machining error. The purpose of this study is to improve the structural design of crossrail in order to minimize it's distortion. Tool Center Point (TCP) was chosen as a reference point for evaluating the distortion effect of a crossrail and topological optimization was adopted as a method of structural design improvement. The displacements of TCP according to the machining positions were investigated by structural analyses for both of original crossrail design and the improved one. The comparing results showed that the displacement of TCP could be reduced about 55% maximum.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.10a
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• pp.202-206
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• 1997

항공기 부품, 터빈형 임펠라나 브레이드, 자동차나 가전제품용의 대형금형류의 정밀가공과 생산성 향상에는 5축의 NC가공이 기존 3축의 NC 가공보다 많은 이점을 갖고 있다. 제1차 선도기술개발사업을 통해 C 형의 5축머시닝센터를 성공적으로 개발한 실적을 바탕으로 제2차 선도기술개발사업을 통해 작업이송거리 12,000*3,500*1,500(X*Y*Z), 위치정밀도 $\pm0.005mm/M$, 주축동력 30/45Kw의 대형, 강력, 정밀형의 문형5축머시닝센터 개불을 목표로 추진하고 있다.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.122-128
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• 2015

Recently, as the demand for high efficiency, multi-function machine tools has increased, domestic machine tool industries are investing in research and development for Gantry-Type Machining centers. In this thesis, for the purpose of evaluating machining accuracy and designing a machine tool structure, a simplified model of the main frame is suggested. The results show the general characteristics of the optimum design, and the approach is shown as practicable for the preliminary design analysis and improvement of a conceptual design of a Gantry-Type Machining center. This paper's results are expected to improve the static characteristics of Gantry-Type Machine centers. The three-dimensional finite element models proved that the modeling method might be applied to real machine tool structures.