• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.150-156
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• 1996

Static variations of cutting forces are estimated using spindle motor current. Static sensitivity of spindle motor current is higher than feed motor current. The linear relationship between the cutting force and RMS value of the spindle motor current is obtained. Using cutting force estimation, tool overload in milling process can be well detected, and cutting force is regulated at a constant level by feedrate adaptive control.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제31회 춘계학술대회
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• pp.68-75
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• 2000

The development of flexible automation in the manufacturing industry is concerned with production activities performed by unmanned machining system. A major topic relevant to metal-cutting operations is monitoring tool wear, which affects process efficiency and product quality, and implementing automatic tool replacements. In this paper, the measurement of the cutting force components has been found to provide a method for an in-process detection of tool wear. Cutting force components are divided into static and dynamic components in this paper, and the static components of cutting force have been used to detect flank wear. To eliminate the influence of variations in cutting conditions, tools, and workpiece materials, the force modeling is performed for various cutting conditions. The normalized force disparities are defined in this paper, and the relationships between normalized disparity and flank wear are established. Finally, Artificial neural network is used to learn these relationships and detect tool wear. According to the proposed method, the static force components could provide the effective means to detect flank wear for varying cutting conditions in turning operation.

• 한국정밀공학회지
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• 제12권2호
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• pp.87-96
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• 1995

The cutting force is the most important variable to understand the mechanics of ultra-precision machining. Most dynamometers, however, monitor the static cutting force only. But it is necessary to measure the dynamic cutting force to clarify the machinability of the material, the formation of the chip, chatter and the wear of the tool. In this research, measurement of the dynamic cutting force in order to clarify the machin-ability of the material, the formation of the chip, chatter and the wear of the tool has been conducted. A combined-type dynamometer which could measure the static cutting force and the dynamic cutting force by use of strain gauges and a piezo-film accelerometer has been developed. An analysis of the dynamometer also has been carried out.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.1088-1094
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• 1997

An indirect cutting torque and cutting force estimation method is presented. This method uses a time-domain model between the spindle motor power, which calculated form measured spindle motor current and voltage. Spindle motor power is linear with cutting torque in this model. The cutting force is proportional to the cutting torque. Using trial cut, parameters are determined. Static sensitivity is suitable for various cutting conditions. The presented method is verified under several cutting tests on the CNC horizontal machining center.

• 한국정밀공학회지
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• 제3권2호
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• pp.91-101
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• 1986

This paper deals with the effect of static and dynamic cuttig force and the behaviour of drill life in drilling process. The experiments are performed with cemented carbide drills and high speed steel drills of 10mm in diameter and in an annealed SM45C. The conclusions are as follows (1) Dynamic cutting force is varied with the dept of hole. (2) Dynamic cutting forces of torque and thrust are increase with the increase in feed and cutting speed. (3) Chipping influence the dynamic cutting force of thrust than torque, and in the case of thrust, the amplitude is 3-7 times large than ordinary cutting state. (4) Prediction of drill life can be obtained from more easily the amplitude of static cutting force than that of dynamic cutting force.

• 한국정밀공학회지
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• 제10권2호
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• pp.161-169
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• 1993

The elimination of chatter vibration is necessary to improve the precision and the productivity of the cutting operation. A new mathematical model of chatter vibration is presented in order to predict the dynamic cutting force from the static cutting data. The dynamic cutting force is analytically expressed by the static cutting coefficient and the dynamic cutting coefficient which can be determined from the cutting mechanics. The stability analysis is carried out by a two degree of freedom system. The chatter experiments are conducted by exciting the cutting tool with an impact hammer during an orthogonal cutting. A good agreement is shown between the stability limits predicted by theory and the critical width of cut determined by experiments.

• 한국정밀공학회지
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• 제14권10호
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• pp.15-27
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• 1997

Quasti-static cutting force variations in milling process are measured indirectly using spindle motor current. Quasi-static sensitivity of the spindle motor current is higher than that of the feed motor current. Magnitude of the spindle motor current is independent of cutting direction. The linear relationship between the cutting force and the spimdle motor RMS current at various spindle rotational speed is obtained. Frequency/ Voltage(F/V) converter voltage is measured to identify the spindle speed and to determine the cutting force at various spindle speeds. Overload on the tool during milling process can be detected using the proposed indirect cutting force measurement. Based on these measurements, cutting force is regulated at a constant level by feedrate control.

• 대한기계학회논문집
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• 제13권3호
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• pp.424-432
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• 1989

본 연구에서는 정적절삭실험으로 결정될수 있는 절삭변수로 표현되는 동적 절삭력을 해석적으로 구한다. 이 모델은 3차원 절삭형태에도 적용될 수 있는 특성을 갖는다. 새로이 제안된 절삭 과정의 모델은 동적절삭상태에서 절삭력 합력의 변화를 고려한 절삭기구를 통해 이루어지며, 해석적으로 한계절삭폭을 구한다. 실험적 규명 은 채터진동이 발생하지 않는 한계절삭 공작물에 비해 공구의 강성이 상대적으로 적은 보링(boring)작업에서 발생하는 것을 대상으로 하였다.

• 한국공작기계학회논문집
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• 제10권1호
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• pp.1-9
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• 2001

The development of flexible automation in the manufacturing industry is concerned with production activities performed by unmanned machining system A major topic relevant to metal-cutting operations is monitoring toll wear, which affects process efficiency and product quality, and implementing automatic toll replacements. In this paper, the measurement of the cutting force components has been found to provide a method for an in-process detection of tool wear. The static com-ponents of cutting force have been used to detect flank wear. To eliminate the influence of variations in cutting conditions, tools, and workpiece materials, the force modeling is performed for various cutting conditions. The normalized force dis-parities are defined in this paper, and the relationships between normalized disparity and flank were are established. Final-ly, artificial neural network is used to learn these relationships and detect tool wear. According to proposed method, the static force components could provide the effective means to detect flank wear for varying cutting conditions in turning operation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1992년도 춘계학술대회 논문집
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• pp.28-32
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• 1992

The elimination of chatter vibration is necessary to improve the precision and the productivity of the cutting operation. A new mathematical model of chatter vibration is pressented in order to predict dynamic cutting force from static cutting data. Chatter vibration occurring in the tool structure of lathe is treated theoretically, considering the regenerative effect. The Stability Analysis is carried out by a two degress of freedom system. The dynamic cutting force is analytically expressed by the static cutting coefficient and the dynamic cutting coeccicient which can be determined from the cutting mechanics. The static cutting coefficient controls high speed chatter stability, while the dynamic cutting coefficient dominates low chatter stability. From above considerations, the cirtical width of cut which governs chatter stability was obtained.