• Proceedings of the KAIS Fall Conference
• /
• 2011.05a
• /
• pp.382-384
• /
• 2011

경계석을 제작하는 제조 공정 중 모서리를 가공하는 공정은 인력의 숙련도와 분진 등의 악조건의 환경에서 인력에 의존하는 강도 높은 제조 공정이다. 특히 인력에 의존하다보니 효율성과 정확성이 현저하게 떨어지는 것이 기존의 상황이다. 본 연구는 이와 같은 일련의 작업을 가공기를 통한 자동화 장비를 통하여 수행 할 수 있도록 설계, 제작하였으며 경계석용 모서리 자동 모따기 가공기를 개발하기 위한 기구적 설계, 제어 방법을 연구하였다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.5
• /
• pp.122-130
• /
• 2018

The International Maritime Organization has enacted mandatory performance standards for protective coatings (PSPC), and as a result, shipyards must perform 2R or 3-pass milling on the edges of color plates. However, manual milling could result in many problems in terms of work environment and productivity. Therefore, it is necessary to develop an edge milling automation system that can satisfy the regulations. In this study, a basic design for an edge milling automation system was developed for standard color plates, and the machining process was established by applying shape recognition and a machining path generation algorithm. In addition, operating software was developed, and suitable milling conditions were derived based on the results of a milling test. The results could be used to build an automation system that meets the PSPC requirements and improve productivity.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.922-925
• /
• 2000

As mechanical components require size minimization and high precision, micro die machining technology has been developed in many fields. to machine a micro die by EDM, sometimes, a polygonal electrode is use. Machining corners by MEDM shows special characteristics. Physically, electrons are concentrated in sharp region and a high potential level is established in this region. Also, the electrode can't be rotated when machining a polygonal cavity, and machined debris can not drawn off easily. Discharge concentration in corners and 2nd discharge by machined debris result in distortion of corner shape. This phenomena can be improved by shaking the electrode. This method is also shown to be effective in improving surface roughness by circulation of machining fluid resulting from movement of the electrode.

• Composites Research
• /
• v.31 no.5
• /
• pp.246-250
• /
• 2018

In this paper, laser ultrasonic rotation scanning method was proposed to inspect and visualize defects in corner section of curved composite structure. L-shaped composite specimen with defects in its corner section were inspected using laser ultrasonic rotation scanning method. L-shaped specimens had artificial defects at three different depths to simulate delamination damage. All artificial defects were detected clearly in different time-of-flight according to their depths. Inspection result showed that the proposed method is suitable to inspect round corner section of curved composite structure without any special tools.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.12
• /
• pp.14-23
• /
• 1999

This paper proposes a method to generate the velocity trajectory which guarantees user specified contour errors at corners for high speed and high precision motion control of CNC machines. The relation among the desired trajectory, system bandwidth and corner contour error are derived. Experiments show that the corner contour error specified by users can be guaranteed with the proposed velocity trajectory.

• Proceedings of the KSME Conference
• /
• 2001.11a
• /
• pp.389-395
• /
• 2001

To restrain contact failure, present study investigates the influence of edge machining of an indenter (punch). As for the edge machining, rounding, chamfering, and chamfering and rounding are considered. Contact mechanics is consulted to examine the traction profile and the size of the contact region which are directly influenced by the end profile of the indenter. The effect of rounding size (i.e., radius) in the case of the chamfering and rounding edge-indenter is studied. Shear traction is also evaluated within the regime of partial slip. Size of slip region and its expansion rate due to the increase of shear force are considered to investigate the shape effect of the indenter on contact failure.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1998.06a
• /
• pp.148-155
• /
• 1998

A trapexoidal cup of corner angles, 72。 and 102。 has been drawn to 45mm in depth. Strains on the corner flange with an acute corner angle have been compared with those on the corner flange of a square cup and those on the corner flange with an obtuse corner angle respectively. The result has shown that the strains of an acute corner angle have been relieved more than those of a square cup in case of the same conditions except of the corner angles.

• Tribology and Lubricants
• /
• v.31 no.4
• /
• pp.170-176
• /
• 2015

As a continuation of Part I, which developed a design formula of the minimum corner radius (R_min) for restraining tribological failures, Part II investigates design parameters such as material properties and contact force. As design examples, Al 7075-T651, SST 304 and HT-9 are chosen for the materials and 1, 10 and 100 kN are used for the forces. The results show that the difference in R_min decreases as either the elastic modulus increases or the contact force decreases. Given the same material and force, the permissible R_min decreases as the flat region increases and vice versa. Because the R_min values obtained from the examples are very small, the dimensions of the corner radius normally designed in engineering structures are regarded acceptable. The von Mises stress evaluated for a typical example, which is far below the yield strength, confirms this interpretation. Nevertheless, the present work can provide a design criterion as well as a guideline for quality control in the manufacturing of, in particular, contact corners, which has not been attempted before to the best of the author’s knowledge. In addition, this paper considers the problem of a step that may be formed in the contact contour by using a similar approach. The result shows that no size of the step is permissible.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.695-698
• /
• 2000

Round-cornering machines are mainly used for cornering of stiffners for ship buildings. In the present time they have been operated manually by operators. so they are need to be operated automatically without regard to any shapes of stiffners. We developed the automatic round cornering system which consists of CCd Camera, PC and laser diode to detect automatically the edge of stiffners to be processed

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.14 no.4
• /
• pp.769-776
• /
• 1990

본 연구에서는 소재형상을 미끄름선장법으로 구하고, 이것을 등고컵(cup with uniform height이하 h-uni cup)을 얻을 수 있는 이상적인 소재형상으로 보았으며, 이 로 부터 8각형을 소재로 취할 경우의 최적 모따기 량을 얻고, 또 정사각형 소재도 포 함하여 세가지 소재형상을 대상으로 하여, 광범위한 펀치의 모서리반경에 따른 한계드 로잉비(L.D.R), 유효 컵높이, 드로잉하중, 두께 분포 등을 고찰하였다.