• 한국기계가공학회지
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• 제16권5호
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• pp.7-12
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• 2017

It is assumed that the buckling and cutting conditions depending on the slenderness ratio will affect the machining quality of the rotary boring tool mounted on a milling machine. In this study, the boring cutter was designed and fabricated to precisely create the Ø30 hole. Through the performance evaluation, the accuracy of the hole according to the slenderness ratio and cutting conditions was analyzed, and the following conclusions were obtained. The higher the RPM, the smaller the change in the working diameter, and the smaller the hole. Next, the smaller the slenderness ratio, the smaller the change in straightness due to the change in cutting conditions. Finally, the slenderness ratio also affects the tendency for changes in the concentricity. The larger the slenderness ratio, the more sensitive the concentricity to changes in cutting conditions.

• 한국생산제조학회지
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• 제9권2호
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• pp.72-79
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• 2000

A new optimal tool design model which can be minimized the resultant cutting forces under the constrains of variables was developed. The resultant cutting forces are used as the objective function and tool angles are used as the variables. Cutting experiments of tool wear and chip length using the new and conventional tools wee carried out. Tool life of optimized cutter are more increased than those of conventional cutter by 2.29 times and 2.52 times at light and at heavy cutting conditions respectively. Chip length of optimized cutter are more increased than those of conventional cutter It is considered that the decrease of the resultant cutting forces is the cause that an effective rake and shear angles by the shape of optimal cutter.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.873-877
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• 1997

This paper presents experimental results to know the charcteristics of machined surface due to cutter runout. Cutter runout is a common but undesirable phenomenon in multi-tooth machining such as end-milling process because it introduces variable chip loading to insert which results in a accelerated tool wear, amplification of force variation and hence enargement vibration amplitude. To develop in-proess cutter runout compensation system, set-up the micro-positoning mechanism which is based on piezoelectric translator embeded in the work holder to manipulate the depth of cut in real-time. And feasibility test of system was done under the various experimental cutting conditions. This results provide lots of information to build-up the precision machining technology.

• 한국터널지하공간학회 논문집
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• 제20권1호
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• pp.161-182
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• 2018

본 연구에서는 퇴적층 암석에서 픽 커터의 절삭성능을 평가하기 위하여 선형절삭시험을 수행하였다. 중국에서 채취된 Linyi사암과 역암을 모사한 콘크리트를 시험체로 사용하였다. 소규모 선형절삭시험장비를 이용하여 다양한 절삭조건하에서 절삭조건에 따른 커터작용력과 비에너지의 변화양상을 평가하였다. 커터작용력은 두 가지 재료 모두에서 압입깊이와 커터간격이 증가함에 따라 증가하는 경향을 나타내었고 재료의 강도에 영향을 받는 것으로 나타났다. 반면 최대작용력과 평균작용력의 비율은 재료의 강도에 영향을 받기 보다는 재료의 구성 물질과 절삭특성에 영향을 받는 것으로 판단되었다. 절삭계수는 암석과 픽 커터의 마찰 특성에 영향을 받으나 절삭조건에는 영향을 받지 않는 것으로 나타났다. 따라서 절삭계수와 픽 커터 작용력의 합력방향에 따라 암석의 특성을 고려한 최적의 절삭각도를 선정해야 할 것으로 판단되었다. 한편 절삭조건에 따른 비에너지의 변화양상으로부터 최적 절삭조건을 규명하였다. 두 가지 재료에서 최적 s/p비는 2~4 범위로 도출되었고, 압입깊이가 증가함에 따라 비에너지는 감소하는 경향을 나타내었다. 본 연구의 결과는 픽 커터의 절삭메커니즘 규명을 위한 데이터베이스로 활용될 수 있으며, 픽 커터를 사용한 기계굴착장비의 설계에 활용될 수 있을 것으로 기대된다.

• Journal of Biosystems Engineering
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• 제30권3호
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• pp.166-171
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• 2005

A prototype peeling device with rotating cutter blades was designed to peel altari radish skin. With the designed blades, the maximum peeling depth increased as the cutter clearance increased but the effect of the peeling speed was not significant. The optimal operating conditions for peeling was; the peeling speed was at 0.19m/s when peeled 2.5 blades/sec and the maximum peeling depth was 1.5mm, the minimum peeling depth was 0.5mm, and the leaf rotating speed was 12 rpm, respectively. In the peeling test fur the optimum operation conditions, with a auxiliary rolling device could adjust the rotational speed of the root uniformly, the altari radishes under 70mm diameter were peeled perfectly.

• 품질경영학회지
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• 제44권4호
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• pp.935-949
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• 2016

Purpose: This study attempts to find out the optimum condition of the rotary cutter making pellet in the footwear outsole process. The pellets are used in the process of outsole rubber fabrication to reduce cycle time and save raw material. Methods: Computer simulations are used to analyze the maximum stress in the rotary cutter after designing a variety of cutter shapes. Taguchi method is used to identify the robust condition of the cutter. In $L_{18}$ orthogonal array, the control factors such as knife width, twisted angle, number of knives, diameter, knife depth and supported angle are considered and noise factors like assembly tolerance and amount of antifriction are allocated. Results: It is found that the most important factors to reduce maximum stress in the cutter are supported angle and diameter. Using Tacuchi's results, we can reduce 70% cycle time and 9% raw material compared to the traditional method using cutting die. Conclusion: When designing the rotary cutter, the best conditions are the diameter at its maximum allowable value and supported angle in the boundary of machine inner space.

• 한국생산제조학회지
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• 제6권4호
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• pp.19-26
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• 1997

The manufacture of an impeller typically requires the 5-axis CNC machining, since the impeller is usually under working conditions such as high speed, high temperature, and high pressure. Thus, this study contributes to development of an exclusive CAM system for effective 5-axis CNC machining of a ruled surface type impeller. In this study, the sampled impeller is made of blades and a body and the blade consists of ruled surfaces between hub curve and shroud curve. In the post processing for 5-axis NC part program, the cutter axis direction vector is the straighten vector on ruled surface. The position of ball center in ball end mill cutter is decided on the interference check between the cutter and body surface of impeller using with the modified z-map method that z-axis is the same of cutter axis direction vector. The exclusive CAM system for an impeller developed in this study was very effective for designs and 50-axis machining of a ruled surface type impeller.

• 드라이브 ㆍ 컨트롤
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• 제21권1호
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• pp.53-58
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• 2024

With the recent development of intelligence and automation technologies for construction machinery, the demand for safety and efficiency of road-cutting operations has continued to increase. In response to this, a double-blade road cutter has been developed that can automatically cut roads. However, a double-blade road cutter has a load difference between the two blades due to the ground and wear conditions of the cutting blades. The difference in load between the two blades distorts the direction of travel of the cutter. In this study, a vision sensor-based driving guide technology was developed to correct the driving path of road cutters. In addition, we developed a load-sensing technology that detects blade loads in real-time and controls driving speed in the event of overload.

• 한국습지학회지
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• 제15권1호
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• pp.51-58
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• 2013

본 연구에서는 준설용 커터헤드의 형태에 따른 준설효율 특성을 분석하기 위하여 개방형 및 폐쇄형으로 나누어 수리실험을 수행하였다. 준설효율에 관한 실험을 수행하기 위하여 $4.9m(L){\times}2.2m(W){\times}1.5m(H)$ 크기의 대형수조를 제작한 후 준설 운영에 필요한 여러 장치를 제작하였다. 준설효율 실험에서는 커터헤드의 준설깊이, 회전속도, 흡입속도 등에 관한 운영조건을 달리하여 실험을 수행하였다. 준설효율에 관한 실험 결과를 살펴보면 개방형의 경우보다 폐쇄형의 경우에 상당히 높은 준설효율을 유지하였다. 동일한 커터헤드의 형태에서는 커터헤드의 회전속도가 준설효율 결과에 가장 큰 영향을 미쳤으며, 보다 높은 준설효율을 위해서는 적정수준의 흡입속도가 필요한 것으로 나타났다.

• 한국터널지하공간학회 논문집
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• 제22권5호
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• pp.501-513
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• 2020

TBM 터널굴착에서 실질적으로 지반을 굴착하는 역할을 하는 부분인 커터헤드 설계 시, 커터 관입깊이와 커터 간격을 달리하여 커터절삭 시험 시 최소 비에너지에서의 커터간격을 반영하고 있으나, 암반 조건에 따라서 동일한 커터 관입깊이에서의 최적 커터간격이 달라지기 때문에 최적 커터간격을 설정하는 연구가 활발히 진행되어야 한다. 이러한 비선형적인 커터 관입깊이와 커터 간격의 관계에서 커터 관입깊이에 따른 최적 커터간격을 예측하기 위해 머신러닝 기법인 의사결정나무 기반 랜덤 포레스트 회귀 모델과 SVM 회귀모델을 이용하여 커터 관입깊이에 따른 최적 커터 간격을 예측하였다. 랜덤 포레스트 분석기법은 SVM 분석기법보다 데이터 개수에 더 큰 영향을 받기 때문에 커터 관입깊이에 따른 최적 커터간격비의 예측에 SVM이 더 정확한 예측을 하였다. 데이터가 많이 축적되면 SVM 회귀모델이 보다 더 정확한 예측값으로 커터헤드 설계 시 커터간격을 설정하는데 효율적으로 사용될 수 있을 것으로 판단된다.