• 한국정밀공학회지
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• 제18권6호
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• pp.133-140
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• 2001

This paper suggests another system for a cutting force measuring tool in a milling process. Generally, tool dynamometer is taken into account for the most appropriate cutting force measuring tool in the analysis of cutting mechanism. However, high price and limited space make it difficult to be in-situ system for controllable milling process. Although an alternative method using AC current of servo-motor has been suggested, it is unsuitable for cutting force control because of small upper frequency limit and noise. The cutting force measuring system is composed of two load cells placed between the moving table bracket and the nut flange part of ballscrew. It has many advantages such as low cost and wide range measurement than tool dynamometer because of the built-in moving table and the low cost load cell. The static and dynamic model of the measuring system using imbeded load cell is introduced. Various Experiments are carried out to validate both models. By comparing the cutting forces from a series of end milling experiments on the tool dynamometer and the system developed in this paper, the accuracy of the cutting force measuring system is verified. Upper frequency limit is measured by the experiment of dynamic characteristics.

• 한국정밀공학회지
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• 제11권2호
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• pp.85-94
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• 1994

The cutting mechanism of ultrasonic vibration machining is characterized as two phases, that is, an impact at the cutting edge and a reduction of cutting force due to non-contact interval between tool and workpiece. In this paper, in order to identify cutting dynamics of a system with ultrasonically vibrated cutting tool, an ARMA modeling is performed on experimental cutting force signals which have a dominant effect on cutting dynamics. The aim of this study is, through Dynamic Date System methodology, to find the inherent characteristics of an ultrasonic vibration cutting process by considering natural frequency and damping coefficient. Surface roughness and stability of cutting process under ultrasonic vibration are also considered

• 한국정밀공학회지
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• 제10권4호
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• pp.216-226
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• 1993

Three dimensional cutting is considered as an equivalent orthogonal cutting through the plane containing both the cutting velocity vector and the chip flow velocity vector in dynamic cutting process. An analytical expression of dynamic cutting force is obtained from the cutting parameters determined by the static cutting. Particular attention is paid to the energy supplied to the vibratory system of cutting tool with two degree of freedom. In this approach, the phase lag of the horizontal vibration of the tool behind the vertical vibration and the direction angle of the fluctuating cutting force is considered in point of stability limits. Chatter vibration can be effectively suppressed by relatively increasing the spring constant and the damping coefficient of the cutting system in the vertical cutting force direction. A good agreement is found between the stability limits predicted by theoretical value and experimental results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.185-188
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• 1995

In this paper, We have analyzed dynamic characteristics of cutting force. Test materials are used in the tempered carbon steek and non-tempered carbon steel. The obtained results ase as follows: 1. Cutting force is smaller non-tempered carbon steel than tempered carbon steel when feed speed make a change. 2. Specific cutting force is smaller non-tempered carbon steel than tempered caron steel when cutting depth make a change

• 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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• 제21권5호
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• pp.46-54
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• 2004

A cutting force model predicting the dynamic force induced by the axial vibration of it plate in face milling is introduced. When a plate face is milled, deformation in tool axial direction is considerable. Therefore, cutting forces are affected by not only inner-outer modulation in feed direction but also by axial deformation. A PTP (peak-to-peak) diagram made by the simulated dynamic force model is evaluated. The stability of the face milling process such as the chatter outset, and the stable cutting region can be simply estimated. Simulation results are compared with that of experiment.

• 대한기계학회논문집
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• 제16권12호
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• pp.2268-2278
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• 1992

본 연구에서는 기존의 정절삭력 모델을 이용하여 절삭과정에서 발생되는 동적 인 특성과 공작기계의 구조적인 특성이 상호작용되어 발생되는 절삭력 변동성분들이 고려된 절삭력 모델 즉 동절삭력 모델을 개발하여서 이 모델로부터 예측된 절삭력과 절삭실험 결과를 비교, 분석하여 제시한 모델의 타당성 및 동절삭력 특성을 검토하고 자 한다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1997년도 추계학술대회 논문집
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• pp.171-176
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• 1997

In this paper, We have analyzed dynamic characteristics of cutting force. Test materials are used martensitic heat resisting steel, STS420J2. The obtained results are as follows: 1. Cutting force is smaller make small feed when feed speed make a change. 2. Principal cutting force is smaller make small cutting speed when feed speed make a change.

• 한국정밀공학회지
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• 제11권4호
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• pp.38-46
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• 1994

The vibration amplitude of boring bar is generally large at the tool tip, because it has the high length-diameter(L/D) ratio. A new dynamic cutting force model is presented by considering the change of shear angle under dynamic cutting. The boring bar is modelled as a cantilever with dynamic force acting at the tool end point. Based on this realistic continuous system model, the equation of motion of borring bar is solved by numerical computations. A good agreement is found between the proposed model and the experimental results.

• 한국생산제조학회지
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• 제22권3호
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• pp.437-446
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• 2013

There have been numerous studies on end milling processes. However, these have been restricted to the application of tools for special cutting purposes. A side milling cutter can handle long, deep, and open slots in a more efficient manner, and it provides the best stability and productivity for this type of milling. In this paper, a method to predict the cutting forces in side milling is described, and simulated cutting forces are compared with those obtained by cutting experiments. In particular, the side milling process easily generates relative motion between the tools and the workpiece because it produces intermittent cutting forces that cause vibrations over a wide frequency range. Therefore, the application of a dynamic cutting model instead of a static cutting model is appropriate to forecast the cutting forces more accurately.