• 제목/요약/키워드: machining load

검색결과 179건 처리시간 0.023초

고속 주축의 상태모니터링 및 제어 알고리즘 설계 (Design of High Speed Spindles Active Monitoring and Control Algorithm)

  • 최현진;박철우;배정섭;안정훈;최성대
    • 한국기계가공학회지
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    • 제10권5호
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    • pp.13-19
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    • 2011
  • In this paper, the active monitoring and control system is developed. This system can monitor the status of high the speed spindle in real time during its processing, and can analyze its influence of dimensional accuracy and processing if any, and can control the machining condition to realize the machining system equipped with active monitoring and self-diagnostic features. Machining experiment was performed on 3 materials Al, Brass and S45C in order to derive the relation between active monitoring and control algorithm by the machining load. In addition, we measured surface roughness of processing specimen along with the data change of spindle rotating speed and conveying speed according to variation of machining load. Based on these experiments, we derived relations for each material that can be applied to the control algorithm to allow self control of the rotating speed and conveying speed according to the machining load.

이송률 자동조정을 위한 2차원 칩로드 해석 (Two-dimensional Chip-load Analysis for Automatic Feedrate Adjustment)

  • 배석형;고기훈;최병규
    • 한국CDE학회논문집
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    • 제5권2호
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    • pp.155-167
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    • 2000
  • To be presented is two-dimensional chip-load analysis for cutting-load smoothing which is needed in unmanned machining and high speed machining of sculptured surfaces. Cutter-engagement angle and effective cutting depth are defined as chip-loads which are the geometrical measures corresponding to cutting-load while machining. The extreme values of chip-loads are geometrically derived in the line-line and line-arc-line blocks of the two-dimensional NC-codes. AFA(automatic feedrate adjustment) strategy for cutting-load smoothing is presented based on the chip-load trajectories.

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CAD/CAM시스템을 이용한 상향식 가공에 의한 고효율가공에 관한 연구 (Research on High-Efficiency Machining through Bottom-up Machining using CAD/CAM System)

  • 정대훈;한규택
    • 한국기계가공학회지
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    • 제18권11호
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    • pp.89-95
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    • 2019
  • In this research, the effect of roughing on tool load through bottom-up machining is investigated through actual machining. Generally, through the use of high-speed machining technology, machining methods, such as general roughing, operate by deepening the cutting depth for as long as the tool is able to withstand it, giving a slower feed rate, less cutting depth, and faster feed. However, when the cutting depth is deep, there is a problem in that the stepped shape of the cutting area is increased (e.g., by the shaking of the tool or the chipping load). However, if the cutting is performed less, the cutting time becomes relatively long. To compensate for these drawbacks and extend the service life of the tool, economic efficiency needs to be secured.

화학적 초음파가공을 이용한 유리의 미세가공 (Micro-machining of Glasses using Chemical-assisted Ultrasonic Machining)

  • 전성건;신용주;김병희;김헌영;전병희
    • 대한기계학회논문집A
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    • 제27권12호
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    • pp.2085-2091
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    • 2003
  • An ultrasonic machining process has been known as efficient and economical means fer precision machining of glass or ceramic materials. However, because of its complexity, the mechanism of the machining process is still not well understood. Therefore, it is hard to optimize the process parameters effectively. The conventional ultrasonic machining which uses the abrasive slurry only, furthermore, is time-consuming and gives the relatively rough surface. In order to increase the material removal rate and improve the integrity of the machined surface, we have introduced the novel ultrasonic machining technique, Chemical-assisted UltraSonic Machining(CUSM). The desktop-style micro ultrasonic machine has been developed and the z-axis feed is controlled by the constant load control algorithm. To obtain the chemical effects, the low concentration HF(hydrofluoric acid) solution, which erodes glass, added to alumina slurry. Through various experiments and comparison with conventional results, the superiority of CUSM is verified. MRR increases over 200%, the surface roughness is improved and the machining load decreases dramatically.

AE를 이용한 AFM 연성 영역 가공 특성 연구 (Characteristic of Ductile Regime AFM Machining Using Acoustic Emission)

  • 안병운;이광호;이성환
    • 한국공작기계학회논문집
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    • 제15권4호
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    • pp.15-21
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    • 2006
  • Recently, atomic force microscope(AFM) with suitable tips is being used for nano fabrication/nanometric machining purposes. In this paper, acoustic emission(AE) was introduced to monitor the nanometric machining of brittle materials(silicon) using AFM. In the experiments, AE responses were sampled, as the tip load was linearly increased(ramped load), to investigate the machining characteristics during a continuous movement. By analyzing the experimental results, it can be concluded that measured AE energy is sensitive to changes in the mechanism of material removal including the ductile-brittle transition during the nanometric machining. The critical depth of cut value for the transition is evaluated and discussed.

Study the effect of machining process and Nano Sio2 on GFRP mechanical performances

  • Afzali, Mohammad;Rostamiyan, Yasser
    • Structural Engineering and Mechanics
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    • 제76권2호
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    • pp.175-191
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    • 2020
  • In this study, the effect of Nano silica (SiO2) on the buckling strength of the glass fiber reinforced laminates containing the machining process causes holes were investigated. The tests have been applied on two status milled and non-milled. To promote the mechanical behavior of the fiber-reinforced glass epoxy-based composites, Nano sio2 was added to the matrix to improve and gradation. Nano sio2 is chosen because of flexibility and high mechanical features; the effect of Nanoparticles on surface serenity has been studied. Thus the effect of Nanoparticles on crack growth and machining process and delamination caused by machining has been studied. We can also imply that many machining factors are essential: feed rate, thrust force, and spindle speed. Also, feed rate and spindle speed were studied in constant values, that the thrust forces were studied as the main factor caused residual stress. Moreover, entrance forces were measured by local calibrated load cells on machining devices. The results showed that the buckling load of milled laminates had been increased by about 50% with adding 2 wt% of silica in comparison with the neat damaged laminates while adding more contents caused adverse effects. Also, with a comparison of two milling tools, the cylindrical radius-end tool had less destructive effects on specimens.

압전형 부하 센서링이 장착된 5축 절삭가공기의 고속 주축시스템 설계 (Design of High Speed Spindle for 5-Axis Machining Equipment Equipped with Piezo-Electric Load Sensoring)

  • 최현진;박철우;장은실;김충현;최성대
    • 한국기계가공학회지
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    • 제10권5호
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    • pp.20-25
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    • 2011
  • In this paper, we reviewed the spindle system's motor and bearing and its mode safety for optimal design of a high speed spindle system that exceeds DmN value of 1,500,000. We could verify that it has a separation margin during critical speed by performing critical speed analysis. Also, we have selected an optimal sensoring installation location and actually manufactured & installed the sensor by identifying the stress concentration position in the axial load through finite element analysis to install the built-in piezo electric type load sensor to the spindle housing that can measure and monitor the machining load during high speed rotation of the spindle. Reproducibility is also verified by calibrating the error through the sensor's sensitivity adjustment after comparing the output between the plate dynamoneters and the load sensor to confirm the reproducibility of the load sensor.

최적조건 선정을 위한 Pad 특성과 Wafer Final Polishing의 가공표면에 관한 연구 (The Study on the Wafer Surface and Pad Characteristic for Optimal Condition in Wafer Final Polishing)

  • 원종구;이은상;이상균
    • 한국기계가공학회지
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    • 제11권1호
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    • pp.26-32
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    • 2012
  • Polishing is one of the important methods in manufacturing of Si wafers and in thinning of completed device wafers. This study will report the characteristic of wafer according to processing time, machining speed and pressure which have major influence on the abrasion of Si wafer polishing. It is possible to evaluation of wafer abrasion by load cell and infrared temperature sensor. The characteristic of wafer surface according to processing condition is selected to use a result data that measure a pressure, machining speed, and the processing time. This result is appeared by the characteristic of wafer surface in machining condition. Through that, the study cans evaluation a wafer characteristic in variable machining condition. It is important to obtain optimal condition. Thus the optimum condition selection of ultra precision Si wafer polishing using load cell and infrared temperature sensor. To evaluate each machining factor, use a data through each sensor. That evaluation of abrasion according to variety condition is selected to use a result data that measure a pressure, machining speed, and the processing time. And optimum condition is selected by this result.

CAD 모델에 기초한 모사절삭을 통한 가상절삭 시스템 개발 (Development of a Virtual Machining System by a CAD Model Based Cutting Simulation)

  • 배대위;고태조;김희술
    • 한국생산제조학회지
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    • 제8권3호
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    • pp.83-91
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    • 1999
  • In this paper, we suggest a virtual machining system that can simulate cutting forces of ball end milling at the stage of part design. Cutting forces, here, are estimated from the machanistic model that uses the concept of specific cutting farce coefficient. To this end, we need undeformed chip thickness which is used for calculating chip load. It is derived from the Z-map data of a CAD model. That is, chip load is the height difference between the cutting tool and the workpiece at an arbitrary position. The tool contact point is referred from the cutter location data. On the other hand, the workpiece height is acquired from the Z-map model of a CAD data. From the experimental verification, we can simulate machining process effectively to the slot and the side cutting of ball end mill.

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고속 볼 엔드밀 가공에서 절삭속도 최적화 (Optimization cutting speed in high speed ball end milling)

  • 김경균;강명창;정융호;이득우;김정석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.895-898
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    • 2001
  • This paper presents an optimization cutting speed(OCS) program developed to improve the machining precision and tool life in high speed machining using ball end milling. This program optimized the cutting speed that is changing at any time in free surface machining of an automobile part like a connecting load die. The technique of optimization cutting speed makes the CAD/CAM-generated NC code go through a reverse post process, conducts cutting simulation, and obtain the effective tool diameter of the ball end milling. Then it changes the spindle revolution to within the range of critical cutting speed fit for the material of the workpieces depending upon the effective tool diameter. In this study, the machining precision and tool life were compared for the two connecting load dies processed using the general cutting method and the proposed optimization cutting speed technique, respectively.

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