• Journal of Welding and Joining
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• 제30권2호
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• pp.59-64
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• 2012

Welding is an essential process in the automotive industry. Most welding processes that are used for auto body are spot welding and $CO_2$ welding are used in a small part. In production field, $CO_2$ welding process is decreased and spot welding process is increased due to welding quality is poor and defects are occurred in $CO_2$ welding process frequently. But $CO_2$ welding process should be used at robot interference parts and closed parts where spot welding couldn't. Because of the 0.65mm ~ 2.0mm thickness steel sheet were used in the automotive industry, poor quality of welding area such as burn through and under fill were happened frequently in $CO_2$ process. In this paper, we will study about the penetration depth which gives a huge impact on burn through changing a degree of base metal, welding position and torch angle. Voltage, current and welding speed were fixed but degree of base metal, welding position and torch angle were changed. And Cold- Rolled(CR) steel sheet was used. Penetration depth was analysed by multiple regression analysis to derive approximate calculations. And reliability of approximate calculations were confirmed through additional experiments. As the results of this research, we confirmed the effect of torch and plate angle to bead shape. And we present a possibility that can simulate more accurate to weld geometry, as deduced the verification equations that has tolerance of less than 21.69%.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 추계 학술대회논문집
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• pp.229-234
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• 2005

Following the recent trend in the automotive manufacturing technologies, the product design subject to the die casting becomes more and more complex. The requirement of the die design becomes more demanding than ever before. In some cases the product's shape can have multiple slender manifolds. In such cases, design of the inlet and outlet parts of the die is very important in the whole manufacturing process. The main issues required for the qualified products are to attain gentle and uniform flow of the molten liquid within the passages of the die. To satisfy such issues, the inlet cylinder ('bed cylinder' in this paper) must be as large as possible and simultaneously the outlet opening at the end of each passage must be as small as possible. However these in turn obviously bring additional manufacturing costs caused by re-melting of the bed cylinder and increased power due to the small outlet-openings. The purpose of this paper is to develop effective simulation methods of calculation for fluid flows in multiple columns, which mimic the actual complex design, and to get some useful information which can give some contributions to the die-casting industry. We have used a commercial code CFX in the numerical simulation. The primary parameter involved is the size of the air-vent. We will show how the very small opening of the outlet, i.e. the air-vent, can be treated with the aid of the porous model provided in the code. To check the validity of the numerical results we have also conducted a simple experiment by using water.

• 한국정보시스템학회지:정보시스템연구
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• 제12권2호
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• pp.129-149
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• 2003

One of the important applications in Enterprise Resource Planning(ERP) systems is the Manufacturing Resource Planning(MRPII) system using Bill of Material(BOM). The manufacturing resource planning determines the quantity and timing of the production or purchase of subassemblies and raw materials needed to support the Master Production Scheduling(MPS). The bill of material is the recipe, a list of the materials needed to make a product. This paper intends to suggest a component-based materials management system using Unified Modeling Language(UML), as an application system for automobile part industry. Applying component based materials management systems designed with UML methodology, we analyzed the workflow and the document on materials management process from production planning to inventory management, and implemented a prototype of efficient materials management system, as a surrogate of existing material requirement planning(MRPI) system. To produce many other assemblies for a automobile part firm, component parts are assembled into subassemblies that are joined to assemble the finished product. Through the system suggested in this study, the level of inventory has cut down and the cost of inventory management has decreased. Also, the development method using UML makes the analysis and design phase to shorten in implementation period of MRPII system. The implementation of materials management system using CBD shows the ease of use in software reuse and the interoperability with corporate Internal information system. The result of applying object-oriented CBD technique is to minimize the risk of life cycle and facilitate the reuse of software as mentioned to limitation of information engineering methodology.

• 한국기계가공학회지
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• 제11권6호
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• pp.130-138
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• 2012

There are increasing demands from the industry for intelligent robot-calibration solutions, which can be tightly integrated to the manufacturing process. A proposed solution can simplify conventional robot-calibration and teaching methods without tedious procedures and lengthy training time. iGPS(Indoor GPS) system is a laser based real-time dynamic tracking/measurement system. The key element is acquiring and reporting three-dimensional(3D) information, which can be accomplished as an integrated system or as manual contact based measurements by a user. A 3D probe is introduced as the user holds the probe in his hand and moves the probe tip over the object. The X, Y, and Z coordinates of the probe tip are measured in real-time with high accuracy. In this paper, a new approach of robot-calibration and teaching system is introduced by implementing a 3D measurement system for measuring and tracking an object with motions in up to six degrees of freedom. The general concept and kinematics of the metrology system as well as the derivations of an error budget for the general device are described. Several experimental results of geometry and its related error identification for an easy compensation / teaching method on an industrial robot will also be included.

• 반도체디스플레이기술학회지
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• 제23권2호
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• pp.1-5
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• 2024

In the electronics industry, a lot of research and development is being conducted on electronic component supply, component alignment and insertion, and automation of soldering on the back side of the PCB for automatic PCB assembly. Additionally, as the use of electronic components increases in the automotive component field, there is a growing need to automate the alignment and insertion of components with leads such as transistors, coils, and fuses on PCB. In response to these demands, the types of PCB and parts used have been more various, and as this industrial trend, the quantity and placement of automation equipment that supplies, aligns, inserts, and solders components has become important in PCB manufacturing plants. It is also necessary to reduce the pre-setting time before using each automation equipment. In this study, we propose a method in which a vision system recognizes the type of component and simultaneously corrects alignment errors during the process of aligning and inserting various types of electronic components. The proposed method is effective in manufacturing various types of PCBs by minimizing the amount of automatic equipment inserted after alignment with the component supply device and omitting the preset process depending on the type of component supplied. Also the advantage of the proposed method is that the structure of the existing automatic insertion machine can be easily modified and utilized without major changes.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제3권10호
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• pp.383-392
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• 2014

코팅제에 대한 연구는 고분자 산업에서 가장 보편화되고 활발하게 연구되고 있는 내용의 하나이다. 코팅제는 전자산업, 의료, 광학 분야 등에서 중요성이 더욱 커지고 있으며, 특히 자동차 및 전자부품의 첨단화에 힘입어 코팅제에 대한 성능과 정밀도 등 기술적인 요구사항이 증가하고 있는 추세이다. 또한 방대한 환경 정보와 상황 정보를 기반으로 한 사물 인터넷과 빅데이터 분석 기술의 도입을 통해 산업 현장에서는 더욱 지능화되고 자동화된 시스템과 처리 기술의 필요성이 높아지고 있다. 이에 본 논문에서는 사물 인터넷 기술과 빅데이터 분석을 활용한 실험계획법 기반의 코팅제 배합 데이터에 대한 최적화 모형을 제안한다. 본 논문에서는 실제 생산현장에서 사용하는 코팅제 배합 기준 데이터와 발생한 오차에 대하여 작업자가 수정한 보정 결과 데이터를 실험계획법을 기반으로 분석하여 최적의 코팅제 배합 기준 데이터를 계산하였다. 또한 빅데이터 분석 기술과 사물 인터넷 기술을 활용하여 기존의 코팅제 배합 기준 데이터만을 적용한 공정이 아니라 제조 환경 정보와 상황 정보를 이용하여 색상과 품질 유지에 가장 중요한 인자를 검색하고 기준값을 보정하는 최적화 모형을 도출하였다. 실험 및 분석을 통해 확보된 기준 데이터는 제조 공정에 적용할 경우 배합의 정확도 향상과 LOT별 작업시간 단축을 가능하게 해주고, 건당 처리시간의 감소로 인한 생산 납품시간 단축, 불량률 감소 등에 따른 원가 절감에 기여할 수 있다. 또한, 다양한 모델링에 대한 제조 공정에서의 표준 데이터를 획득할 수 있다.

• 한국CDE학회논문집
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• 제21권4호
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• pp.389-396
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• 2016

The necessity for environment-friendly material development has emerged in the recent automotive field due to stricter regulations on fuel economy and environmental concerns. Accordingly, the automotive industry is paying attention to carbon fiber reinforced plastic (CFRP) material with high strength and stiffness properties while the lightweight. In this study, we determine a shape of lower control arm (LCA) for maximizing the strength and stiffness by optimizing the thickness of each layer when the stacking angle is fixed due to the CFRP manufacturing problems. Composite materials are laminated in the order of $0^{\circ}$, $90^{\circ}$, $45^{\circ}$, and $-45^{\circ}$ with a symmetrical structure. For the approximate optimal design, we apply a sequential two-point diagonal quadratic approximate optimization (STDQAO) and use a process integrated design optimization (PIDO) code for this purpose. Based on the physical properties calculated within a predetermined range of laminate thickness, we perform the FEM analysis and verify whether it satisfies the load and stiffness conditions or not. These processes are repeated for successive improved objective function. Optimized CFRP LCA has the equivalent stiffness and strength with light weight structure when compared to conventional aluminum design.

• 한국자동차공학회논문집
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• 제15권2호
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• pp.115-125
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• 2007

Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke marine diesel engine is of great economic importance. In Korea, a motor-driven cylinder lubricator for a large two-stroke marine diesel engine manufactured by $W{\ddot{a}}rtsil{\ddot{a}}$ Switzerland Co., Ltd. was first developed by authors through the joint research of industry-university in 2002. The characteristic of the developed product is that can control automatically the oil feed rate to a load fluctuation by the motor drive and the offset cam. The performance of the product is not also inferior to the conventional one. For manufacturing the reliable and useful products, however, it is necessary to investigate further characteristics and improve the performance of a cylinder lubricator. In this study, the effect of quill with and without accumulator on maximum discharge pressure, delivery delay duration and oil feed rate relative to motor revolution speed using plunger stroke as a parameter is experimentally investigated by using the developed cylinder lubricator. It is found that the maximum discharge pressure with accumulator is higher than that of no accumulator as plunger stroke and motor revolution speed are elevated, and the delivery delay duration with accumulator is shorter than that of no accumulator as plunger stroke and motor revolution speed are increased. Also, oil feed rate with accumulator is less than that of no accumulator except for a plunger stroke of 2 mm as plunger stroke and motor revolution speed are raised.

• 통상정보연구
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• 제15권2호
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• pp.71-82
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• 2013

자동차 공급망은 자동차기업들이 글로벌화되어 아웃소싱이 일반화되고 해외생산기지를 구축함에 따라 지속적으로 복잡하게 되었다. 자동차산업에서 순환물류용기 (RPC: Returnable Plastic Container) 의 사용은 물류효율과 비용절감 측면에서 매우 일반화되어 있으나 주로 내수용으로 활용하고 있으며 국제무역용으로는 절대적인 운송거리가 길고 운영관리가 복잡해져 크게 활용되지 않고 있다. 이 연구는 시뮬레이션을 통하여 1회용기와 반복사용이 가능한 순환물류용기를 pooling system으로 적용하는 경우 기업에 미치는 경제적 영향을 비교하였다. 결론적으로 미국과 같은 장거리 국제물류에서는 순환물류용기의 사용이 어려우나 중국과 일본과 같이 비교적 단거리 국제무역에서는 pooling 시스템의 도입으로 경제적으로 타당한 것으로 나타났다. 이 연구결과는 국제공급망 환경에 따라 경제적으로 최적의 포장방법과 형태의 변화가 필요함을 밝혔다. 다만, 국제무역상 발생하는 통관상의 복잡함, 관세, 국내와 해외 물류환경의 상이로 인한 효율성 저하 등의 문제는 하기 위해서는 보다 많은 연구가 필요하다.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.74-81
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• 2013

The high-speed machining in the manufacturing industry field has been widely applied for parts of vehicles, aircraft, ships, electronics, etc., recently, because the effect of cost savings for shortening processing time and improving productivity is great. The purpose in this study is to investigate the effect of cutting depth on the surface roughness of workpiece with the spindle rotational speed and feed rate of high-speed machines as a parameter to find the optimal depth in the finishing for ball end mill of the aluminum alloy 7075 which is used much in aircraft parts. When the cutting depth for the respective feed rate and spindle rotational speed is varied from 0.1 mm to 0.7 mm at intervals of 0.2 mm in the wet finishing of the aluminum alloy 7075 by the insoluble cutting oils and high-speed machining used in the rough machining of previous study, the surface roughness values and the cutting temperature are measured. In addition, the cutting surface shapes of test specimens are observed by optical microscope and compared with respectively. It is found that the surface roughness values and the temperature generated during machining are increased as the feed rate and cutting depth are raised, but those are decreased as the spindle rotational speed is increased.