• 한국정밀공학회지
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• 제16권10호
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• pp.35-44
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• 1999

The performance of interrupted cutting operations like milling is consideraly affected by cuter runout. In this study, cutter runout is selected as an important machining parameter for evaluation of machinability in ball-end milling and caused from misalignments of tool and holder, unbalanced mass of parts and tool deflection under machining. To evaluate the machinability due to cutter runout, the rotating accuracy of spindle, cutting force and surface roughness are measured. The rotating characteristics of spindle in each revolution speed were investigated by cutter runout in freeload. The predicted surface form of workpiece by measuring cutter runout data was compared with real surfaces. The results show that measuring runout with high response gap sensor is useful for studying the phenomenon of high-speed machining and the monitor surface form using in-process runout measurements in ball-end milling is possible.

• 대한기계학회논문집A
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• 제20권8호
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• pp.2508-2515
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• 1996

Determination of an optimal feed rate is valuable in the sense of the precision and efficient machining. In this regard, a new surface roughness model for the face milling operation that considered the radial and axal runouts of the inserts in the cutter body was developed. The validity of the model was proved through the cutting experiments, and the model is able to predict the real machined surface roughness exactly with the information of the insert runouts and the cutting conditions. From the estimated surface roughness value, the maximum feed rate that obtains a maximum naterial removal rate under the given surface roughness constraint can be selected by using a bisection method. Therefore, this mehod for optimizing the feed rate can be well applied to the using a bisection method. Therefore, this method for optimizing the feed rate can be well applied to the using selsction of the cutting condition during the NC data generation in CAM.

• 한국기계가공학회지
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• 제20권1호
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• pp.57-65
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• 2021

With the increased utilization of CAM programs, end-mill processing is most commonly used for machining and metal processing. In particular, hole or shaft machining has high assembly precision, which inevitably leads to high utilization of end mills. However, the analysis of quality characteristics according to the process conditions of end mills is not performed systematically at the site, causing poor quality and productivity. The most influential factor of quality is the runout of the end mill. In this paper, the number of turns of the end mill, number of tool blades, cutting direction, and artificial runout volume were determined to identify the correlation between the epicenter, cylindricality, and surface roughness. Two types of end mills, three levels of runout, three levels of rotational speed, and two cutting directions were considered and 36 rounds of hole processing were conducted. For the analysis of shape characteristics according to the set process variables, the experimental planning method was applied to the measured specimen and the processing characteristics were analyzed according to the runout of the end mill through correlation analysis.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.357-358
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• 2006

• 한국자동차공학회논문집
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• 제12권5호
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• pp.118-124
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• 2004

To investigate the mechanics of brake squeal noise, the sound and vibration of an actual brake system was measured using a brake dynamometer. The experimental results show that disk run-out due to the misalignment of brake disk varies with brake line pressure and becomes the important factor of brake squeal noise generation. Also, it was confirmed that the frequency of the squeal noise equals to the natural frequency of the disk bending mode.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.183-188
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• 2004

본 연구는 시뮬레이션을 활용하여 장치장의 레이아웃을 설계하고 레이아웃의 대안설계를 평가하기 위한 방법을 제시한 다. 설계방법론은 장치장 레이아웃을 가진 재래식 컨테이너터미널의 개념들을 기초로 한다. 일반적으로 컨테이너터미널의 장치장 설계는 두가지 부분으로 구성되는데, 하나는 섹션수와 런수간의 장치장 면적을 분리하는 것이고, 다른 하나는 야드트럭과 야드크 레인과 같은 장비의 수찰 결정하는 것이다. 과거에는 이 설계가 매우 복잡한 문제이기 때문에 재래식 컨테이너터미널의 복제와 운영자의 경험에 의존했다. 본 논문에서는 개념설계로서 장치장 설계 방법을 제안하며, 시뮬레이션을 사용하여 컨테이너크레인의 효율과 장비의 최적대수를 추정한다. 실험결과로서 장치장 영역에서 섹션과 런의 수, 컨테이너 크레인당 야드트럭의 수, 런당 야드 크레인의 수 똥이 결정된다. 추가로 장치장 레이아웃에서 블록간의 통행량 흐름이 비율별로 추정된다.

• 한국항해항만학회지
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• 제29권8호
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• pp.741-746
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• 2005

본 연구는 시뮬레이션을 활용하여 장치장의 레이아웃을 설계하고 레이아웃의 대안설계를 평가하기 위한 방법을 제안한다. 설계방법론은 장치장 레이아웃을 가진 재래식 컨테이너터미널의 개념들을 기초로 한다. 일반적으로 컨테이너터미널의 장치장 설계는 두가지 부분으로 구성되는데, 하나는 섹션수와 런수간의 장치장 면적을 분리하는 것이고, 다른 하나는 야드트럭과 야드크레인과 같은 장비의 수를 결정하는 것이다. 과거에는 이 설계가 시설물과 장비들을 고려해야 하는 매우 복잡한 문제이기 때문에 재래식 컨테이너터미널의 복제와 운영자의 경험에 의존했다. 본 논문에서는 시뮬레이션 방법이 사용된 개념설계로서 장치장 설계 방법을 제안한다. 장치장 영역에서 섹션과 런의 수, 컨테이너 크레인당 야드트럭의 수, 런딩 야드 크레인의 수 등이 시뮬레이션을 사용하여 결정된다. 추가로 장치장 레이아웃에서 블록간의 통행량 흐름이 비율별로 추정된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.88-93
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• 2001

As the development of High Speed Machining, It is applied in many fields of manufacturing. Among them is to manufacture die and mold. But it still remains as a hard-to-work to apply it in machining pre-hardened materials such as hardened QRO90. It also difficult to machine new materials because there is no machining date of them. Therefore, in this study, we are trying to improve the machinability of new material, QRO90 by applying various cutting conditions, and selecting the best condition which not only reduce the machining time but improve the quality of die and mold made of QRO90 material.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1466-1469
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• 2004

Micro spherical lens mold processing method based on mechanical one completes a spherical shape by setting a diamond tool of hundreds $\mu$m radius on spins with high speed and then using Z-axis vertical feeding motion like the fabrication of micro drilling. In this method, we can see unprocessed parts shaped like cylinder and cone and check increasing chatter marks and burrs by setting errors of the central axis of rotation on the edge of the tool. That is why this method doesn't suit for the optical lens mold. In this paper presents unprocessed parts are disappeared and chatter marks and burrs are decreased from centre of the lens after using Run-out measuring and setting system on run-out occurred from setting tool. Also the fabrication characteristics of 6：4 Brass, A1601, PMMA are compared and analyzed, establishing the optimum machining condition on each material.

• 한국기계가공학회지
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• 제9권6호
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• pp.43-50
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• 2010

This study aims to analyze the structural safety by comparing deformation and equivalent stress of door with a stiffener or no stiffener when the door crashes against something in case of overturn. Three types are classified on the basis of the no stiffener model in the vehicle door. One is the type which has a stiffener. Another is the type which has no stiffener and the other is the type which has a hole in the stiffener. These three types are compared with each other by analyzing. This side door of vehicle is the automotive part about the kind of vehicle as Mercedes Benz E-Klasse scaled down as 1/18 times as the real size. The study model of vehicle door is modelled by CATIA program and it is analyzed by ANSYS.