• 제목/요약/키워드: Cutting Force Coefficients

검색결과 41건 처리시간 0.034초

3축방향의 비절삭 계수를 이용한 정면 밀링 절삭력 모델 개발 (Development of Cutting Force Model for Face Milling Operation Using 3-Directional Specific Cutting Force Coefficients)

  • 김희술;이상석
    • 한국정밀공학회지
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    • 제8권1호
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    • pp.116-129
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    • 1991
  • A cutting force model for face milling operation using 3-directional specific cutting force coefficients is developed. The model is taken into consideration factors such as cutter geometry, machining conditions, spindle eccentricity, insert initial postion errors, etc. The simulated force in X, Y, Z directions from the model are subsequently compared with measured forces in the time and frequency domains. The simulated forces have a good agreement with measured forces.

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신경회로망을 이용한 엔드밀 가공의 비절삭력계수 모델링 (Specific Cutting Force Coefficients Modeling of End Milling by Using Neural Network)

  • 이신영;이장무
    • 대한기계학회논문집A
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    • 제23권6호
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    • pp.979-987
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    • 1999
  • In a high precision vertical machining center, the estimation of cutting forces is important for many reasons such as prediction of chatter vibration, surface roughness and so on, and cutting forces are difficult to predict because they are very complex and time variant. In order to predict the cutting forces of end-milling process for various cutting conditions, a mathematical model is important and this model is based on chip load, cutting geometry, and the relationship between cutting forces and chip loads. Specific cutting force coefficients of the model have been obtained as interpolation function types by averaging farces of cutting tests. In this paper, the coefficients are obtained by neural network and the results of the conventional method and those of the proposed method are compared. The results show that the neural network method gives more correct values than the function type and that in teaming stage as the omitted numbers of experimental data increases the average errors increase.

향상된 절삭력 예측을 위한 Size Effect 모델의 개발 (Development of the Size Effect Model for More Accurate Cutting Force Prediction)

  • 윤원수;조동우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.995-1000
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    • 2000
  • In this paper. a mechanistic model is first constructed to predict three-dimensional cutting forces, and the uncut chip th thickness is calculated by following the movements of the position of the center of a cutter, which varies with the nominal feed, cutter deflection and runout. For general implementation to a real machining, this paper presents the method that determines constant cutting force coefficients, irrespective of the cutting conditions or cutter rotation angles. In addition, this study presents the approach which estimates runout-related parameters. the runout offset and its location angle, using only one measurement of cutting forces. For more accurate cutting force predictions, the size effect has to be considered in the cutting force model. In this paper, two approximate methods are suggested since the strict approach is practically impossible due to a measurement problem. The size effect is individually considered for narrow and wide cuts.

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CNC 가공에서 절삭력 예측과 조절을 위한 절삭 시뮬레이션 시스템 개발 (Development of Cutting Simulation System for Prediction and Regulation of Cutting Force in CNC Machining)

  • 고정훈;이한울;조동우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.3-6
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    • 2002
  • This paper presents the cutting simulation system for prediction and regulation of cutting force in CNC machining. The cutting simulation system includes geometric model, cutting force model, and off-line fred rate scheduling model. ME Z-map(Moving Edge node Z-map) is constructed for cutting configuration calculation. The cutting force models using cutting-condition-independent coefficients are developed for flat-end milling and ball-end milling. The off-line feed rate scheduling model is derived from the developed cutting force model. The scheduled feed rates are automatically added to a given set of NC code, which regulates the maximum resultant cutting force to the reference force preset by an operator. The cutting simulation system can be used as an effective tool for improvement of productivity in CNC machining.

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밀링가공시 절삭조건이 비절삭력계수에 미치는 영향 분석 (Effects of Cutting Conditions on Specific Cutting Force Coefficients in Milling)

  • 이신영
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 춘계학술대회 논문집
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    • pp.93-98
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    • 2004
  • A reasonable analysis of cutting force in end milling may give much advantage to improvement of productivity and cutting tool life. In order to analyze cutting force, the cutting dynamics was modelled mathematically by using chip load, cutting geometry, and the relationship between cutting forces and the chip load. Specific cutting constants of the cutting dynamics model were obtained by average cutting forces, tool diameter, cutting speed, feed, axial depth, and radial depth of cut. The effects of the cutting conditions on the specific cutting force constants in milling were studied. The model is verified through comparisons of model predicted cutting forces with measured culling forces obtained from machining experiments

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인덱서블 엔드밀링 공정을 위한 향상된 절삭력 모델의 개발 (Development of Improved Cutting Force Model for Indexable End Milling Process.)

  • 김성준;이한울;조동우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.237-240
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    • 2004
  • Indexable end mills, which consist of inserts and cutter body, have been widely used in roughing of parts in the mold industry. The geometry and distribution of inserts on cutter body are determined by application. This paper proposes analytical cutting force model for indexable flat end-milling process. Developed cutting force model uses the cutting-condition-independent cutting force coefficients and considers runout, cutter deflection and size effect for the accurate cutting force prediction. Unlike solid type endmill, the tool geometry of indexable endmill is variable according to the axial position due to the geometry and distribution of inserts on the cutter body. Thus, adaptive algorithm that calculates tool geometry data at arbitrary axial position was developed. Then number of flute, angular position of flute, and uncutchip thickness are calculated. Finally, presented model was validated through some experiments with aluminum workpiece.

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CNC 가공의 정밀 절삭 시뮬레이션 및 이송속도 스케줄링 시스템 개발 (Development of Accurate Cutting Simulation and Feedrate Scheduling System for CNC Machining)

  • 이한울;고정훈;조동우
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 춘계학술대회 논문집
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    • pp.370-375
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    • 2004
  • This paper presents an accurate cutting simulation and feedrate scheduling system for CNC machining. This system is composed of a cutting simulation part and a feedrate scheduling part. The cutting simulation part computes the geometric informations and calculates the cutting forces in CNC machining. The cutting force model using cutting-condition-independent coefficients was introduced for flat end milling and ball end milling. The feedrate scheduling part divides original blocks of NC code into smaller ones with optimized feedrates to adjust the peak value of cutting forces to reference forces. Some machining examples show that the developed system can control the cutting force at desired levels.

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기계구조용 탄소강(SM45C)의 단속절삭 시 절삭력예측을 위한 회귀방정식 도출 (Regression Equation Deduction for Cutting Force Prediction during Interrupted Cutting of Carbon Steel for Machine Structure (SM45C))

  • 배명일;이이선
    • 한국기계가공학회지
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    • 제15권4호
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    • pp.40-45
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    • 2016
  • Interrupted cutting has different cutting characteristics compared with continuous cutting. In interrupted cutting, the workpiece has a groove that regularly impacts the cutting tool and workpiece. Therefore, tool damage occurs rapidly, and this increases the cutting force and surface roughness. In this study, we performed interrupted cutting of carbon steel for machine structure (SM45C) using a coated carbide tool (TT7100). To predict the cutting force, we analyzed the experimental results with a regression analysis. The results were as follows: We confirmed that the factors affecting the principal force and radial force were cutting speed, depth of cut, and feed rate. From the multi-regression analysis, we deduced regression equations, and their coefficients of determination were 89.6, 89.27, and 28.27 for the principal, radial, and feed forces, respectively. This means that the regression equations were significant for the principal and radial forces but not for the feed force.

런아웃을 고려한 엔드밀링의 절삭력 모델링 (Cutting Force Modelling in End-milling Considering Runout)

  • 조희근;김종도;윤문철
    • 한국생산제조학회지
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    • 제20권3호
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    • pp.225-231
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    • 2011
  • In this paper, a new end-milling force modelling technique was suggested by considering runout, and its result was compared with real measured force. The specific cutting force is the multiplication of cutting force coefficient and uncut chip thickness. This parameter was used for experimental modelling and prediction of theoretical force. These coefficients, which can be obtained by fitting measured average forces in several conditions, were used for the formulation of theoretical force. The mechanism of end-milling force with runout was developed in this research and its result was verified by comparing the fluctuating theoretical force and its measured one. The fluctuation of force was incurred by a geometric shape of workpiece and its runout in holding. The result of suggested force considering runout shows a good consistency with measured one. So this modelling method can be used effectively for a prediction of end-milling force with runout effect.