• 제목/요약/키워드: Up-cut milling

검색결과 26건 처리시간 0.022초

상향절삭에 의한 깊은 홈 가공시 정밀도 향상에 대한 연구 (Improvement of the Accuracy in Machining Deep Pocket by Up Milling)

  • 이상규;고성림
    • 한국정밀공학회지
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    • 제16권4호통권97호
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    • pp.220-228
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    • 1999
  • The machining accuracy has been improved with the development of NC machine tools and cutting tools. However, it is difficult to obtain a high degree of accuracy when machining deep pocket with long end mill, since machining accuracy is mainly dependant on the stiffness of the cutting tool. To improve surface accuracy in machining deep pocket using end mill, the performance by down cut and up cut is compared theoretically and experimentally. To verify usefulness of up milling, various experiments were carried out. As a result, it is found that up milling produce more accurate surface than down milling in machining deep pocket. For effective application of up milling, various values in helix angle, number of teeth, radial depth of cut and axial depth of cut are applied in experiment.

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가공경로가 밀링가공면의 기하학적 특성에 미치는 영향 (Effects of the Tool Path on the Geometric Characteristics of Milled Surface)

  • 박문진;김강
    • 한국정밀공학회지
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    • 제15권6호
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    • pp.58-63
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    • 1998
  • There are lots of factors that are related to the geometric characteristics of machined surface. Among them, the tool path and milling mode (up cut milling or down cut milling) are the easiest controllable machining conditions. Thus, the first objective of this research is to study the effects of them on the milled surface that is generated by an end milling tool. To get precision parts, not only the machining process but also the measurement of geometric tolerance is important. But, this measurement requires a lot of time, because the infinite surface points must be measured in the ideal case. So, the second objective is to propose a simple flatness measurement method that can be available instead of the 3-D geometric tolerance measurement method, using a scale factor and characterized points. Finally, it is also shown that the possibility of flatness improvement by shifting the consecutive fine cutting tool path as compared with the last rough cutting tool path.

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알루미늄 합금의 스파이럴 상향가공 시 절삭조건이 표면거칠기에 미치는 영향 (Effects of cutting condition on surface roughness in the spiral up milling of aluminum alloy)

  • 천세호
    • 한국기계가공학회지
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    • 제13권4호
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    • pp.83-90
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    • 2014
  • The spiral up milling of an aluminum alloy was performed in this study. In accordance with the cutting condition, the surface roughness behavior and significance of the research with regard to specific factors were analyzed. The cutting speed, feed, and depth of the cut were found to be statistically significant. A higher cutting speed improved the surface roughness. On the other hand, as the feed and depth of the cut increase, the surface roughness decreases. An interaction effect between the feed and depth of the cut was detected. According to the surface roughness in relation to the cutting conditions, the model showed non-linear behavior.

엔드밀 가공에서 형상 정밀도 향상을 위한 절삭 조건 선정 (Cutting Condition Selection for Geometrical Accuracy Improvement in End Milling)

  • 류시형;최덕기;주종남
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1784-1788
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    • 2003
  • For the improvement of geometrical accuracy in end milling, cutting method and cutting condition selection are investigated in this paper. As machining processes are composed of several steps such as roughing, semi-finishing. and finishing, cutting forces and tool deflection are calculated considering surface shape generated by the previous cutting. The effects of tool teeth numbers, tool geometry, and cutting conditions on the form error are analyzed. Using the from error prediction method from tool deflection, cutting condition for geometrical accuracy improvement is discussed. The characteristics and the difference of generated surface shape in up and down milling are dealt with and over-cut free condition in up milling is presented. The form error reduction method by alternating up and down milling is also suggested. The effectiveness of the presented method is examined from a set of cutting tests under various cutting conditions. This research contributes to cutting process optimization for the geometrical accuracy improvement in die and mold manufacture.

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엔드밀 가공의 정밀도 향상을 위한 최적정삭여유에 관한 연구 (A Study on the Optimum Finish Allowance for Machining Accuracy Improvement in the End Milling Processes)

  • 최종근;김형선;김성초
    • 한국공작기계학회논문집
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    • 제13권3호
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    • pp.8-15
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    • 2004
  • A significant error in the end milling processes is generated due to using slender tools of which the strengths are not sufficient. In order to obtain the desired machining accuracy, therefore, it is general that at first the rough cut is implemented, then the finish cut is followed. The rough cut eliminates large volume and the finish cut does the remained part. This remaining portion after the rough cut is called as the finish allowance. Larger finish allowances make it hard to get precise dimensions at a following finish cut. Smaller finish allowances are helpful for good dimension, but it sometimes is responsible for inferior surface qualities and over cuts. This study suggests a guidance for the optimum finish allowance for machining accuracy improvement, in which the rough cuts are regulated to remain the desired margins without any over cuts. Some experiments were carried out with various cutting conditions including the change of tool strengths and depth of cuts, and also extended to up millings as well as down millings.

엔드밀가공에서 커터회전방향에 따른 절삭력의 최적화 (Optimization of Cutting Force for End Milling with the Direction of Cutter Rotation)

  • 최만성
    • 반도체디스플레이기술학회지
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    • 제16권2호
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    • pp.79-84
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    • 2017
  • This paper outlines the Taguchi optimization methodology, which is applied to optimize cutting parameters in end milling when machining STS304 with TiAlN coated SKH59 tool under up and down end milling conditions. The end milling parameters evaluated are depth of cut, spindle speed and feed rate. An orthogonal array, signal-to-noise (S/N) ratio and analysis of variance (ANOVA) are employed to analyze the effect of these end milling parameters. The Taguchi design is an efficient and effective experimental method in which a response variable can be optimized, given various control and noise factors, using fewer resources than a factorial design. An orthogonal array of $L_9(33)$ was used. The most important input parameter for cutting force, however, is the feed rate, and depending on the cutter rotation direction. Finally, confirmation tests verified that the Taguchi design was successful in optimizing end milling parameters for cutting force.

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소형 앵글 스핀들 공구의 절삭성능에 관한 연구 (Cutting Performance of a Developed Small-angle Spindle Tool)

  • 김진수;김용조
    • 한국기계가공학회지
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    • 제15권2호
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    • pp.111-117
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    • 2016
  • The cutting performance of a developed small-angle spindle tool was investigated with Al6061 using a TiAlN coated high-speed steel end mill. Up-cut and down-cut processes in a milling machine were carried out at the range of 1000-4000 rpm for spindle speed and 50-300 mm/min for feed rate. As a result, the highest cutting force in the Fx direction was obtained from the up-cut process when the spindle speed was 1000 rpm and the feed rate was 100 mm/min. In the Fy direction, the highest cutting force appeared in the up-cut process at a feed rate of 250 mm/min at the same spindle speed. Conversely, the lowest cutting force came out in the up-cut process at a spindle speed of 4000 rpm and a feed rate of 50 mm/min. As for surface finish, the finest surface roughness was obtained as Ra 0.7642 um at a spindle speed of 4000 rpm and a feed rate of 50 mm/min. Consequently, given the cutting performance of the developed small-angle spindle tool, we conclude that its use in industrial practice is feasible.

측벽 엔드밀 가공에서 형상 정밀도를 고려한 최적 절삭 조건 (Optimal Cutting Condition in Side Wall Milling Considering Form Accuracy)

  • 류시형;최덕기;주종남
    • 한국정밀공학회지
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    • 제20권10호
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    • pp.31-40
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    • 2003
  • In this paper, optimal cutting condition to minimize the form error in side wall machining with a flat end mill is studied. Cutting forces and tool deflection are calculated considering surface shape generated by the previous cutting such as roughing. Using the form error prediction method from tool deflection, optimal cutting condition considering form accuracy is investigated. Also, the effects of tool teeth number, tool geometry and cutting conditions on form error are analyzed. The characteristics and the difference of generated surface shape in up and down milling are discussed and over-cut free condition in up milling is presented. Form error reduction method through successive up and down milling is also suggested. The effectiveness and usefulness of the presented method are verified from a series of cutting experiments under various cutting conditions. It is confirmed that form error prediction from tool deflection in side wall machining can be used in optimal cutting condition selection and real time surface error simulation for CAD/CAM systems. This study also contributes to cutting process optimization for the improvement of form accuracy especially in precision die and mold manufacturing.

컴퓨터 수치제어 자동차용 키 가공기 제어장치 개발 (A Development of the Control System of the Computer Numerical Controlled Milling Machine for the Automobile Key Mounting)

  • 임동진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 B
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    • pp.675-677
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    • 1998
  • In this paper, a development of the control system for the milling machine which is used to cut teeth of the automibile keys is presented as an example of the industry-university cooperation. The machine is controlled by a computer and a PLC. The control of the servo motors are accomplished by the computer and mechanical sequences are by PLC. This machine is capable of cutting key teeth up to the accuracy of 10 microns.

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엔드밀링 공정의 형상창성기구에 의하여 절삭면적이 측벽 진직도 특성에 미치는 영향 (Effects of Cutting Area on Straightness Characteristics in Side Walls Caused by Form Generation Mechanism in End-Milling Process)

  • 김강
    • 대한기계학회논문집A
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    • 제37권10호
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    • pp.1269-1278
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    • 2013
  • 엔드밀링 공정은 형상창성기구의 특성 상, 절삭면적의 주기적인 변화를 피할 수 없다. 그러므로, 본 연구에서는, 가공 중 절삭날과 공작물 사이의 간섭영역에 해당하는 절삭면적의 모델을 확립하여, 가공면 형상 특성과 절삭면적의 관계를 규명하고자 한다. 대상 가공면은 측벽을 선정하였으며, 형상 특성은 축 방향 진직도를 선택하였다. 절삭면적 및 축방향 진직도에 영향을 미치는 특이점 추정 모델의 타당성은 반경 방향 및 축 방향 절삭깊이를 변화시키며 엔드밀링 가공을 수행하여 검증하였다. 연구 결과, 배분력이 음의 값을 갖지 않는 안정적인 엔드밀링 가공의 경우, 상향절삭은 절삭면적이 증가했다. 일정해지는 영역에서, 하향절삭은 절삭면적이 일정했다 감소하는 영역에서 가공면을 창성하며, 영역이 변화될 때 가공면에 특이점이 발생하는 것이 확인되었다.